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* [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon
@ 2020-05-14  7:23 Stefan Roese
  2020-05-19  6:07 ` Heiko Schocher
                   ` (2 more replies)
  0 siblings, 3 replies; 9+ messages in thread
From: Stefan Roese @ 2020-05-14  7:23 UTC (permalink / raw)
  To: u-boot

From: Suneel Garapati <sgarapati@marvell.com>

Add support for I2C controllers found on Octeon II/III and Octeon TX
TX2 SoC platforms.

Signed-off-by: Aaron Williams <awilliams@marvell.com>
Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Aaron Williams <awilliams@marvell.com>
Cc: Chandrakala Chavva <cchavva@marvell.com>
---
RFC -> v1 (Stefan):
- Separated this patch from the OcteonTX/TX2 RFC patch series into a
  single patch. This is useful, as the upcoming MIPS Octeon support will
  use this I2C driver.
- Added MIPS Octeon II/III support (big endian). Rename driver and its
  function names from "octeontx" to "octeon" to better match all Octeon
  platforms.
- Moved from union to defines / bitmasks as suggested by Simon. This makes
  the driver usage on little- and big-endian platforms much easier.
- Enhanced Kconfig text
- Removed all clock macros (use values from DT)
- Removed long driver debug strings. This is only available when a debug
  version of this driver is built. The user / developer can lookup the
  descriptive error messages in the driver in this case anyway.
- Removed static "last_id"
- Dropped misc blank lines. Misc reformatting.
- Dropped "!= 0"
- Added missing function comments
- Added missing strut comments
- Changed comment style
- Renames "result" to "ret"
- Hex numbers uppercase
- Minor other changes
- Reword commit text and subject

 drivers/i2c/Kconfig      |  10 +
 drivers/i2c/Makefile     |   1 +
 drivers/i2c/octeon_i2c.c | 803 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 814 insertions(+)
 create mode 100644 drivers/i2c/octeon_i2c.c

diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
index e42b6516bf..1330b36698 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -374,6 +374,16 @@ config SYS_I2C_SANDBOX
 	  bus. Devices can be attached to the bus using the device tree
 	  which specifies the driver to use.  See sandbox.dts as an example.
 
+config SYS_I2C_OCTEON
+	bool "Octeon II/III/TX/TX2 I2C driver"
+	depends on (ARCH_OCTEON || ARCH_OCTEONTX || ARCH_OCTEONTX2) && DM_I2C
+	default y
+	help
+	  Add support for the Marvell Octeon I2C driver. This is used with
+	  various Octeon parts such as Octeon II/III and OcteonTX/TX2. All
+	  chips have several I2C ports and all are provided, controlled by
+	  the device tree.
+
 config SYS_I2C_S3C24X0
 	bool "Samsung I2C driver"
 	depends on ARCH_EXYNOS4 && DM_I2C
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index 62935b7ebc..2b58aae892 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -27,6 +27,7 @@ obj-$(CONFIG_SYS_I2C_LPC32XX) += lpc32xx_i2c.o
 obj-$(CONFIG_SYS_I2C_MESON) += meson_i2c.o
 obj-$(CONFIG_SYS_I2C_MVTWSI) += mvtwsi.o
 obj-$(CONFIG_SYS_I2C_MXC) += mxc_i2c.o
+obj-$(CONFIG_SYS_I2C_OCTEON) += octeon_i2c.o
 obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
 obj-$(CONFIG_SYS_I2C_RCAR_I2C) += rcar_i2c.o
 obj-$(CONFIG_SYS_I2C_RCAR_IIC) += rcar_iic.o
diff --git a/drivers/i2c/octeon_i2c.c b/drivers/i2c/octeon_i2c.c
new file mode 100644
index 0000000000..210f98655e
--- /dev/null
+++ b/drivers/i2c/octeon_i2c.c
@@ -0,0 +1,803 @@
+// SPDX-License-Identifier:    GPL-2.0
+/*
+ * Copyright (C) 2018 Marvell International Ltd.
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <dm.h>
+#include <pci_ids.h>
+#include <asm/io.h>
+#include <asm/arch/clock.h>
+#include <linux/bitfield.h>
+
+/*
+ * Octeon II/III (MIPS) have different register offsets than the ARM based
+ * Octeon TX/TX2 SoCs
+ */
+#if defined(CONFIG_ARCH_OCTEON)
+#define REG_OFFS		0x0000
+#else
+#define REG_OFFS		0x1000
+#endif
+
+#define TWSI_SW_TWSI		(REG_OFFS + 0x00)
+#define TWSI_TWSI_SW		(REG_OFFS + 0x08)
+#define TWSI_INT		(REG_OFFS + 0x10)
+#define TWSI_SW_TWSI_EXT	(REG_OFFS + 0x18)
+
+#define TWSI_SW_DATA_MASK	GENMASK_ULL(31, 0)
+#define TWSI_SW_EOP_IA_MASK	GENMASK_ULL(34, 32)
+#define TWSI_SW_IA_MASK		GENMASK_ULL(39, 35)
+#define TWSI_SW_ADDR_MASK	GENMASK_ULL(49, 40)
+#define TWSI_SW_SCR_MASK	GENMASK_ULL(51, 50)
+#define TWSI_SW_SIZE_MASK	GENMASK_ULL(54, 52)
+#define TWSI_SW_SOVR		BIT_ULL(55)
+#define TWSI_SW_R		BIT_ULL(56)
+#define TWSI_SW_OP_MASK		GENMASK_ULL(60, 57)
+#define TWSI_SW_EIA		GENMASK_ULL(61)
+#define TWSI_SW_SLONLY		BIT_ULL(62)
+#define TWSI_SW_V		BIT_ULL(63)
+
+#define TWSI_INT_SDA_OVR	BIT_ULL(8)
+#define TWSI_INT_SCL_OVR	BIT_ULL(9)
+#define TWSI_INT_SDA		BIT_ULL(10)
+#define TWSI_INT_SCL		BIT_ULL(11)
+
+enum {
+	TWSI_OP_WRITE	= 0,
+	TWSI_OP_READ	= 1,
+};
+
+enum {
+	TWSI_EOP_SLAVE_ADDR = 0,
+	TWSI_EOP_CLK_CTL = 3,
+	TWSI_SW_EOP_IA   = 6,
+};
+
+enum {
+	TWSI_SLAVEADD     = 0,
+	TWSI_DATA         = 1,
+	TWSI_CTL          = 2,
+	TWSI_CLKCTL       = 3,
+	TWSI_STAT         = 3,
+	TWSI_SLAVEADD_EXT = 4,
+	TWSI_RST          = 7,
+};
+
+enum {
+	TWSI_CTL_AAK	= BIT(2),
+	TWSI_CTL_IFLG	= BIT(3),
+	TWSI_CTL_STP	= BIT(4),
+	TWSI_CTL_STA	= BIT(5),
+	TWSI_CTL_ENAB	= BIT(6),
+	TWSI_CTL_CE	= BIT(7),
+};
+
+/*
+ * Internal errors. When debugging is enabled, the driver will report the
+ * error number and the user / developer can check the table below for the
+ * detailed error description.
+ */
+enum {
+	/** Bus error */
+	TWSI_STAT_BUS_ERROR		= 0x00,
+	/** Start condition transmitted */
+	TWSI_STAT_START			= 0x08,
+	/** Repeat start condition transmitted */
+	TWSI_STAT_RSTART		= 0x10,
+	/** Address + write bit transmitted, ACK received */
+	TWSI_STAT_TXADDR_ACK		= 0x18,
+	/** Address + write bit transmitted, /ACK received */
+	TWSI_STAT_TXADDR_NAK		= 0x20,
+	/** Data byte transmitted in master mode, ACK received */
+	TWSI_STAT_TXDATA_ACK		= 0x28,
+	/** Data byte transmitted in master mode, ACK received */
+	TWSI_STAT_TXDATA_NAK		= 0x30,
+	/** Arbitration lost in address or data byte */
+	TWSI_STAT_TX_ARB_LOST		= 0x38,
+	/** Address + read bit transmitted, ACK received */
+	TWSI_STAT_RXADDR_ACK		= 0x40,
+	/** Address + read bit transmitted, /ACK received */
+	TWSI_STAT_RXADDR_NAK		= 0x48,
+	/** Data byte received in master mode, ACK transmitted */
+	TWSI_STAT_RXDATA_ACK_SENT	= 0x50,
+	/** Data byte received, NACK transmitted */
+	TWSI_STAT_RXDATA_NAK_SENT	= 0x58,
+	/** Slave address received, sent ACK */
+	TWSI_STAT_SLAVE_RXADDR_ACK	= 0x60,
+	/**
+	 * Arbitration lost in address as master, slave address + write bit
+	 * received, ACK transmitted
+	 */
+	TWSI_STAT_TX_ACK_ARB_LOST	= 0x68,
+	/** General call address received, ACK transmitted */
+	TWSI_STAT_RX_GEN_ADDR_ACK	= 0x70,
+	/**
+	 * Arbitration lost in address as master, general call address
+	 * received, ACK transmitted
+	 */
+	TWSI_STAT_RX_GEN_ADDR_ARB_LOST	= 0x78,
+	/** Data byte received after slave address received, ACK transmitted */
+	TWSI_STAT_SLAVE_RXDATA_ACK	= 0x80,
+	/** Data byte received after slave address received, /ACK transmitted */
+	TWSI_STAT_SLAVE_RXDATA_NAK	= 0x88,
+	/**
+	 * Data byte received after general call address received, ACK
+	 * transmitted
+	 */
+	TWSI_STAT_GEN_RXADDR_ACK	= 0x90,
+	/**
+	 * Data byte received after general call address received, /ACK
+	 * transmitted
+	 */
+	TWSI_STAT_GEN_RXADDR_NAK	= 0x98,
+	/** STOP or repeated START condition received in slave mode */
+	TWSI_STAT_STOP_MULTI_START	= 0xa0,
+	/** Slave address + read bit received, ACK transmitted */
+	TWSI_STAT_SLAVE_RXADDR2_ACK	= 0xa8,
+	/**
+	 * Arbitration lost in address as master, slave address + read bit
+	 * received, ACK transmitted
+	 */
+	TWSI_STAT_RXDATA_ACK_ARB_LOST	= 0xb0,
+	/** Data byte transmitted in slave mode, ACK received */
+	TWSI_STAT_SLAVE_TXDATA_ACK	= 0xb8,
+	/** Data byte transmitted in slave mode, /ACK received */
+	TWSI_STAT_SLAVE_TXDATA_NAK	= 0xc0,
+	/** Last byte transmitted in slave mode, ACK received */
+	TWSI_STAT_SLAVE_TXDATA_END_ACK	= 0xc8,
+	/** Second address byte + write bit transmitted, ACK received */
+	TWSI_STAT_TXADDR2DATA_ACK	= 0xd0,
+	/** Second address byte + write bit transmitted, /ACK received */
+	TWSI_STAT_TXADDR2DATA_NAK	= 0xd8,
+	/** No relevant status information */
+	TWSI_STAT_IDLE			= 0xf8
+};
+
+#ifndef CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR
+# define CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR	0x77
+#endif
+
+/**
+ * struct octeon_twsi - Private data of this driver
+ *
+ * @base:	Base address of i2c registers
+ */
+struct octeon_twsi {
+	void __iomem *base;
+};
+
+static void twsi_unblock(void *base);
+static int twsi_stop(void *base);
+
+#if defined(CONFIG_ARCH_OCTEON)
+static int get_io_clock(void)
+{
+	return octeon_get_io_clock();
+}
+#else
+static int get_io_clock(void)
+{
+	return octeontx_get_io_clock();
+}
+#endif
+
+static int twsi_thp(void)
+{
+	if (IS_ENABLED(CONFIG_ARCH_OCTEON) || IS_ENABLED(CONFIG_ARCH_OCTEONTX))
+		return 24;
+	else
+		return 3;
+}
+
+/**
+ * Returns true if we lost arbitration
+ *
+ * @code	status code
+ * @final_read	true if this is the final read operation
+ * @return	true if arbitration has been lost, false if it hasn't been lost.
+ */
+static int twsi_i2c_lost_arb(u8 code, int final_read)
+{
+	switch (code) {
+	case TWSI_STAT_TX_ARB_LOST:
+	case TWSI_STAT_TX_ACK_ARB_LOST:
+	case TWSI_STAT_RX_GEN_ADDR_ARB_LOST:
+	case TWSI_STAT_RXDATA_ACK_ARB_LOST:
+		/* Arbitration lost */
+		return -EAGAIN;
+
+	case TWSI_STAT_SLAVE_RXADDR_ACK:
+	case TWSI_STAT_RX_GEN_ADDR_ACK:
+	case TWSI_STAT_GEN_RXADDR_ACK:
+	case TWSI_STAT_GEN_RXADDR_NAK:
+		/* Being addressed as slave, should back off and listen */
+		return -EIO;
+
+	case TWSI_STAT_SLAVE_RXDATA_ACK:
+	case TWSI_STAT_SLAVE_RXDATA_NAK:
+	case TWSI_STAT_STOP_MULTI_START:
+	case TWSI_STAT_SLAVE_RXADDR2_ACK:
+	case TWSI_STAT_SLAVE_TXDATA_ACK:
+	case TWSI_STAT_SLAVE_TXDATA_NAK:
+	case TWSI_STAT_SLAVE_TXDATA_END_ACK:
+		/* Core busy as slave */
+		return  -EIO;
+
+	case TWSI_STAT_RXDATA_ACK_SENT:
+		/* Ack allowed on pre-terminal bytes only */
+		if (!final_read)
+			return 0;
+		return -EAGAIN;
+
+	case TWSI_STAT_RXDATA_NAK_SENT:
+		/* NAK allowed on terminal byte only */
+		if (!final_read)
+			return 0;
+		return -EAGAIN;
+
+	case TWSI_STAT_TXDATA_NAK:
+	case TWSI_STAT_TXADDR_NAK:
+	case TWSI_STAT_RXADDR_NAK:
+	case TWSI_STAT_TXADDR2DATA_NAK:
+		return -EAGAIN;
+	}
+
+	return 0;
+}
+
+#define RST_BOOT_PNR_MUL(val)  (((val) >> 33) & 0x1F)
+
+/**
+ * Writes to the MIO_TWS(0..5)_SW_TWSI register
+ *
+ * @base	Base address of i2c registers
+ * @val		value to write
+ * @return	0 for success, otherwise error
+ */
+static u64 twsi_write_sw(void __iomem *base, u64 val)
+{
+	unsigned long start = get_timer(0);
+
+	val &= ~TWSI_SW_R;
+	val |= TWSI_SW_V;
+
+	debug("%s(%p, 0x%llx)\n", __func__, base, val);
+	writeq(val, base + TWSI_SW_TWSI);
+	do {
+		val = readq(base + TWSI_SW_TWSI);
+	} while ((val & TWSI_SW_V) && (get_timer(start) < 50));
+
+	if (val & TWSI_SW_V)
+		debug("%s: timed out\n", __func__);
+	return val;
+}
+
+/**
+ * Reads the MIO_TWS(0..5)_SW_TWSI register
+ *
+ * @base	Base address of i2c registers
+ * @val		value for eia and op, etc. to read
+ * @return	value of the register
+ */
+static u64 twsi_read_sw(void __iomem *base, u64 val)
+{
+	unsigned long start = get_timer(0);
+
+	val |= TWSI_SW_R | TWSI_SW_V;
+
+	debug("%s(%p, 0x%llx)\n", __func__, base, val);
+	writeq(val, base + TWSI_SW_TWSI);
+
+	do {
+		val = readq(base + TWSI_SW_TWSI);
+	} while ((val & TWSI_SW_V) && (get_timer(start) < 50));
+
+	if (val & TWSI_SW_V)
+		debug("%s: Error writing 0x%llx\n", __func__, val);
+
+	debug("%s: Returning 0x%llx\n", __func__, val);
+	return val;
+}
+
+/**
+ * Write control register
+ *
+ * @base	Base address for i2c registers
+ * @data	data to write
+ */
+static void twsi_write_ctl(void __iomem *base, u8 data)
+{
+	u64 val;
+
+	debug("%s(%p, 0x%x)\n", __func__, base, data);
+	val = data | FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CTL) |
+		FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
+	twsi_write_sw(base, val);
+}
+
+/**
+ * Reads the TWSI Control Register
+ *
+ * @base	Base address for i2c
+ * @return	8-bit TWSI control register
+ */
+static u8 twsi_read_ctl(void __iomem *base)
+{
+	u64 val;
+
+	val = FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CTL) |
+		FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
+	val = twsi_read_sw(base, val);
+
+	debug("%s(%p): 0x%x\n", __func__, base, (u8)val);
+	return (u8)val;
+}
+
+/**
+ * Read i2c status register
+ *
+ * @base	Base address of i2c registers
+ * @return	value of status register
+ */
+static u8 twsi_read_status(void __iomem *base)
+{
+	u64 val;
+
+	val = FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_STAT) |
+		FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
+
+	return twsi_read_sw(base, val);
+}
+
+/**
+ * Waits for an i2c operation to complete
+ *
+ * @param	base	Base address of registers
+ * @return	0 for success, 1 if timeout
+ */
+static int twsi_wait(void __iomem *base)
+{
+	unsigned long start = get_timer(0);
+	u8 twsi_ctl;
+
+	debug("%s(%p)\n", __func__, base);
+	do {
+		twsi_ctl = twsi_read_ctl(base);
+		twsi_ctl &= TWSI_CTL_IFLG;
+	} while (!twsi_ctl && get_timer(start) < 50);
+
+	debug("  return: %u\n", !twsi_ctl);
+	return !twsi_ctl;
+}
+
+/**
+ * Unsticks the i2c bus
+ *
+ * @base	base address of registers
+ */
+static int twsi_start_unstick(void __iomem *base)
+{
+	twsi_stop(base);
+	twsi_unblock(base);
+
+	return 0;
+}
+
+/**
+ * Sends an i2c start condition
+ *
+ * @base	base address of registers
+ * @return	0 for success, otherwise error
+ */
+static int twsi_start(void __iomem *base)
+{
+	int ret;
+	u8 stat;
+
+	debug("%s(%p)\n", __func__, base);
+	twsi_write_ctl(base, TWSI_CTL_STA | TWSI_CTL_ENAB);
+	ret = twsi_wait(base);
+	if (ret) {
+		stat = twsi_read_status(base);
+		debug("%s: ret: 0x%x, status: 0x%x\n", __func__, ret, stat);
+		switch (stat) {
+		case TWSI_STAT_START:
+		case TWSI_STAT_RSTART:
+			return 0;
+		case TWSI_STAT_RXADDR_ACK:
+		default:
+			return twsi_start_unstick(base);
+		}
+	}
+
+	debug("%s: success\n", __func__);
+	return 0;
+}
+
+/**
+ * Sends an i2c stop condition
+ *
+ * @base	register base address
+ * @return	0 for success, -1 if error
+ */
+static int twsi_stop(void __iomem *base)
+{
+	u8 stat;
+
+	twsi_write_ctl(base, TWSI_CTL_STP | TWSI_CTL_ENAB);
+
+	stat = twsi_read_status(base);
+	if (stat != TWSI_STAT_IDLE) {
+		debug("%s: Bad status on bus@%p\n", __func__, base);
+		return -1;
+	}
+
+	return 0;
+}
+
+/**
+ * Writes data to the i2c bus
+ *
+ * @base	register base address
+ * @slave_addr	address of slave to write to
+ * @buffer	Pointer to buffer to write
+ * @length	Number of bytes in buffer to write
+ * @return	0 for success, otherwise error
+ */
+static int twsi_write_data(void __iomem *base, u8  slave_addr,
+			   u8 *buffer, unsigned int length)
+{
+	unsigned int curr = 0;
+	u64 val;
+	int ret;
+
+	debug("%s(%p, 0x%x, %p, 0x%x)\n", __func__, base, slave_addr,
+	      buffer, length);
+	ret = twsi_start(base);
+	if (ret) {
+		debug("%s: Could not start BUS transaction\n", __func__);
+		return -1;
+	}
+
+	ret = twsi_wait(base);
+	if (ret) {
+		debug("%s: wait failed\n", __func__);
+		return ret;
+	}
+
+	val = (u32)(slave_addr << 1) | TWSI_OP_WRITE |
+		FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
+		FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
+	twsi_write_sw(base, val);
+	twsi_write_ctl(base, TWSI_CTL_ENAB);
+
+	debug("%s: Waiting\n", __func__);
+	ret = twsi_wait(base);
+	if (ret) {
+		debug("%s: Timed out writing slave address 0x%x to target\n",
+		      __func__, slave_addr);
+		return ret;
+	}
+
+	ret = twsi_read_status(base);
+	debug("%s: status: 0x%x\n", __func__, ret);
+	if (ret != TWSI_STAT_TXADDR_ACK) {
+		debug("%s: status: 0x%x\n", __func__, ret);
+		twsi_stop(base);
+		return twsi_i2c_lost_arb(ret, 0);
+	}
+
+	while (curr < length) {
+		val = buffer[curr++] |
+			FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
+			FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
+		twsi_write_sw(base, val);
+		twsi_write_ctl(base, TWSI_CTL_ENAB);
+
+		debug("%s: Writing 0x%llx\n", __func__, val);
+
+		ret = twsi_wait(base);
+		if (ret) {
+			debug("%s: Timed out writing data to 0x%x\n",
+			      __func__, slave_addr);
+			return ret;
+		}
+		ret = twsi_read_status(base);
+		debug("%s: status: 0x%x\n", __func__, ret);
+	}
+
+	debug("%s: Stopping\n", __func__);
+	return twsi_stop(base);
+}
+
+/**
+ * Manually clear the I2C bus and send a stop
+ *
+ * @base	register base address
+ */
+static void twsi_unblock(void __iomem *base)
+{
+	int i;
+
+	for (i = 0; i < 9; i++) {
+		writeq(0, base + TWSI_INT);
+		udelay(5);
+		writeq(TWSI_INT_SCL_OVR, base + TWSI_INT);
+		udelay(5);
+	}
+	writeq(TWSI_INT_SCL_OVR | TWSI_INT_SDA_OVR, base + TWSI_INT);
+	udelay(5);
+	writeq(TWSI_INT_SDA_OVR, base + TWSI_INT);
+	udelay(5);
+	writeq(0, base + TWSI_INT);
+	udelay(5);
+}
+
+/**
+ * Performs a read transaction on the i2c bus
+ *
+ * @base	Base address of twsi registers
+ * @slave_addr	i2c bus address to read from
+ * @buffer	buffer to read into
+ * @length	number of bytes to read
+ * @return	0 for success, otherwise error
+ */
+static int twsi_read_data(void __iomem *base, u8 slave_addr,
+			  u8 *buffer, unsigned int length)
+{
+	unsigned int curr = 0;
+	u64 val;
+	int ret;
+
+	debug("%s(%p, 0x%x, %p, %u)\n", __func__, base, slave_addr,
+	      buffer, length);
+	ret = twsi_start(base);
+	if (ret) {
+		debug("%s: start failed\n", __func__);
+		return ret;
+	}
+
+	ret = twsi_wait(base);
+	if (ret) {
+		debug("%s: wait failed\n", __func__);
+		return ret;
+	}
+
+	val = (u32)(slave_addr << 1) | TWSI_OP_READ |
+		FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
+		FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
+	twsi_write_sw(base, val);
+	twsi_write_ctl(base, TWSI_CTL_ENAB);
+
+	ret = twsi_wait(base);
+	if (ret) {
+		debug("%s: waiting for sending addr failed\n", __func__);
+		return ret;
+	}
+
+	ret = twsi_read_status(base);
+	debug("%s: status: 0x%x\n", __func__, ret);
+	if (ret != TWSI_STAT_RXADDR_ACK) {
+		debug("%s: status: 0x%x\n", __func__, ret);
+		twsi_stop(base);
+		return twsi_i2c_lost_arb(ret, 0);
+	}
+
+	while (curr < length) {
+		twsi_write_ctl(base, TWSI_CTL_ENAB |
+			       ((curr < length - 1) ? TWSI_CTL_AAK : 0));
+
+		ret = twsi_wait(base);
+		if (ret) {
+			debug("%s: waiting for data failed\n", __func__);
+			return ret;
+		}
+
+		val = twsi_read_sw(base, val);
+		buffer[curr++] = (u8)val;
+	}
+
+	twsi_stop(base);
+
+	return 0;
+}
+
+/**
+ * Calculate the divisor values
+ *
+ * @speed	Speed to set
+ * @m_div	Pointer to M divisor
+ * @n_div	Pointer to N divisor
+ * @return	0 for success, otherwise error
+ */
+static void twsi_calc_div(unsigned int speed, int *m_div, int *n_div)
+{
+	int io_clock_hz;
+	int tclk, fsamp;
+	int ndiv, mdiv;
+
+#if defined(CONFIG_ARCH_OCTEON) || defined(CONFIG_ARCH_OCTEONTX)
+	io_clock_hz = get_io_clock();
+	tclk = io_clock_hz / (2 * (twsi_thp() + 1));
+#elif defined(CONFIG_ARCH_OCTEONTX2)
+	/* Refclk src in mode register defaults to 100MHz clock */
+	io_clock_hz = 100000000; /* 100 Mhz */
+	tclk = io_clock_hz / (twsi_thp() + 2);
+#endif
+	debug("%s( io_clock %u tclk %u)\n", __func__, io_clock_hz, tclk);
+
+	/*
+	 * Compute the clocks M divider:
+	 *
+	 * TWSI freq = (core freq) / (10 x (M+1) x 2 * (thp+1) x 2^N)
+	 * M = ((core freq) / (10 x (TWSI freq) x 2 * (thp+1) x 2^N)) - 1
+	 *
+	 * For OcteonTX2 -
+	 * TWSI freq = (core freq) / (10 x (M+1) x (thp+2) x 2^N)
+	 * M = ((core freq) / (10 x (TWSI freq) x (thp+2) x 2^N)) - 1
+	 */
+	for (ndiv = 0; ndiv < 8; ndiv++) {
+		fsamp = tclk / (1 << ndiv);
+		mdiv = fsamp / speed / 10;
+		mdiv -= 1;
+		if (mdiv < 16)
+			break;
+	}
+
+	*m_div = mdiv;
+	*n_div = ndiv;
+}
+
+/**
+ * Init I2C controller
+ *
+ * @base	Base address of twsi registers
+ * @slave_addr	I2C slave address to configure this controller to
+ * @return	0 for success, otherwise error
+ */
+static int twsi_init(void __iomem *base, int slaveaddr)
+{
+	u64 val;
+
+	debug("%s (%p, 0x%x)\n", __func__, base, slaveaddr);
+
+	val = slaveaddr << 1 |
+		FIELD_PREP(TWSI_SW_EOP_IA_MASK, 0) |
+		FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
+		TWSI_SW_V;
+	twsi_write_sw(base, val);
+
+	/* Set slave address */
+	val = slaveaddr |
+		FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_EOP_SLAVE_ADDR) |
+		FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
+		TWSI_SW_V;
+	twsi_write_sw(base, val);
+
+	return 0;
+}
+
+/**
+ * Transfers data over the i2c bus
+ *
+ * @bus		i2c bus to transfer data over
+ * @msg		Array of i2c messages
+ * @nmsgs	Number of messages to send/receive
+ * @return	0 for success, otherwise error
+ */
+static int octeon_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
+			   int nmsgs)
+{
+	struct octeon_twsi *twsi = dev_get_priv(bus);
+	int ret;
+	int i;
+
+	debug("%s: %d messages\n", __func__, nmsgs);
+	for (i = 0; i < nmsgs; i++, msg++) {
+		debug("%s: chip=0x%x, len=0x%x\n", __func__, msg->addr,
+		      msg->len);
+
+		if (msg->flags & I2C_M_RD) {
+			debug("%s: Reading data\n", __func__);
+			ret = twsi_read_data(twsi->base, msg->addr,
+					     msg->buf, msg->len);
+		} else {
+			debug("%s: Writing data\n", __func__);
+			ret = twsi_write_data(twsi->base, msg->addr,
+					      msg->buf, msg->len);
+		}
+		if (ret) {
+			debug("%s: error sending\n", __func__);
+			return -EREMOTEIO;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * Set I2C bus speed
+ *
+ * @bus		i2c bus to transfer data over
+ * @speed	Speed in Hz to set
+ * @return	0 for success, otherwise error
+ */
+static int octeon_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
+{
+	struct octeon_twsi *twsi = dev_get_priv(bus);
+	int m_div, n_div;
+	u64 val;
+
+	debug("%s(%p, %u)\n", __func__, bus, speed);
+
+	twsi_calc_div(speed, &m_div, &n_div);
+	if (m_div >= 16)
+		return -1;
+
+	val = (u32)(((m_div & 0xf) << 3) | ((n_div & 0x7) << 0)) |
+		FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CLKCTL) |
+		FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
+		TWSI_SW_V;
+	/* Only init non-slave ports */
+	writeq(val, twsi->base + TWSI_SW_TWSI);
+
+	debug("%s: Wrote 0x%llx to sw_twsi\n", __func__, val);
+	return 0;
+}
+
+/**
+ * Driver probe function
+ *
+ * @dev		I2C device to probe
+ * @return	0 for success, otherwise error
+ */
+static int octeon_pci_i2c_probe(struct udevice *dev)
+{
+	struct octeon_twsi *twsi = dev_get_priv(dev);
+#if !defined(CONFIG_ARCH_OCTEON)
+	pci_dev_t bdf = dm_pci_get_bdf(dev);
+
+	debug("TWSI PCI device: %x\n", bdf);
+	dev->req_seq = PCI_FUNC(bdf);
+
+	twsi->base = dm_pci_map_bar(dev, PCI_BASE_ADDRESS_0,
+				    PCI_REGION_MEM);
+#else
+	twsi->base = dev_remap_addr(dev);
+#endif
+	debug("TWSI bus %d at %p\n", dev->seq, twsi->base);
+
+	/* Start with standard speed, real speed set via DT or cmd */
+	return twsi_init(twsi->base, CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR);
+}
+
+static const struct dm_i2c_ops octeon_i2c_ops = {
+	.xfer		= octeon_i2c_xfer,
+	.set_bus_speed	= octeon_i2c_set_bus_speed,
+};
+
+static const struct udevice_id octeon_i2c_ids[] = {
+	{ .compatible = "cavium,thunder-8890-twsi" },
+	{ .compatible = "cavium,octeon-7890-twsi" },
+	{ }
+};
+
+U_BOOT_DRIVER(octeon_pci_twsi) = {
+	.name	= "i2c_octeon",
+	.id	= UCLASS_I2C,
+	.of_match = octeon_i2c_ids,
+	.probe	= octeon_pci_i2c_probe,
+	.priv_auto_alloc_size = sizeof(struct octeon_twsi),
+	.ops	= &octeon_i2c_ops,
+};
+
+#if !defined(CONFIG_ARCH_OCTEON)
+static struct pci_device_id octeon_twsi_supported[] = {
+	{ PCI_VDEVICE(CAVIUM, PCI_DEVICE_ID_CAVIUM_TWSI) },
+	{ },
+};
+
+U_BOOT_PCI_DEVICE(octeon_pci_twsi, octeon_twsi_supported);
+#endif
-- 
2.26.2

^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon
  2020-05-14  7:23 [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon Stefan Roese
@ 2020-05-19  6:07 ` Heiko Schocher
  2020-05-26  6:49   ` Stefan Roese
  2020-05-19 12:32 ` Simon Glass
  2020-06-03  5:15 ` Rayagonda Kokatanur
  2 siblings, 1 reply; 9+ messages in thread
From: Heiko Schocher @ 2020-05-19  6:07 UTC (permalink / raw)
  To: u-boot

Hello Stefan,

Am 14.05.2020 um 09:23 schrieb Stefan Roese:
> From: Suneel Garapati <sgarapati@marvell.com>
> 
> Add support for I2C controllers found on Octeon II/III and Octeon TX
> TX2 SoC platforms.
> 
> Signed-off-by: Aaron Williams <awilliams@marvell.com>
> Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
> Signed-off-by: Stefan Roese <sr@denx.de>
> Cc: Heiko Schocher <hs@denx.de>
> Cc: Simon Glass <sjg@chromium.org>
> Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
> Cc: Aaron Williams <awilliams@marvell.com>
> Cc: Chandrakala Chavva <cchavva@marvell.com>
> ---
> RFC -> v1 (Stefan):
> - Separated this patch from the OcteonTX/TX2 RFC patch series into a
>    single patch. This is useful, as the upcoming MIPS Octeon support will
>    use this I2C driver.
> - Added MIPS Octeon II/III support (big endian). Rename driver and its
>    function names from "octeontx" to "octeon" to better match all Octeon
>    platforms.
> - Moved from union to defines / bitmasks as suggested by Simon. This makes
>    the driver usage on little- and big-endian platforms much easier.
> - Enhanced Kconfig text
> - Removed all clock macros (use values from DT)
> - Removed long driver debug strings. This is only available when a debug
>    version of this driver is built. The user / developer can lookup the
>    descriptive error messages in the driver in this case anyway.
> - Removed static "last_id"
> - Dropped misc blank lines. Misc reformatting.
> - Dropped "!= 0"
> - Added missing function comments
> - Added missing strut comments
> - Changed comment style
> - Renames "result" to "ret"
> - Hex numbers uppercase
> - Minor other changes
> - Reword commit text and subject
> 
>   drivers/i2c/Kconfig      |  10 +
>   drivers/i2c/Makefile     |   1 +
>   drivers/i2c/octeon_i2c.c | 803 +++++++++++++++++++++++++++++++++++++++
>   3 files changed, 814 insertions(+)
>   create mode 100644 drivers/i2c/octeon_i2c.c

nitpick only ...

Please add a documentation of the device tree bindings.

[...]
> diff --git a/drivers/i2c/octeon_i2c.c b/drivers/i2c/octeon_i2c.c
> new file mode 100644
> index 0000000000..210f98655e
> --- /dev/null
> +++ b/drivers/i2c/octeon_i2c.c
> @@ -0,0 +1,803 @@
> +// SPDX-License-Identifier:    GPL-2.0
> +/*
> + * Copyright (C) 2018 Marvell International Ltd.
> + */
> +
> +#include <common.h>
> +#include <i2c.h>
> +#include <dm.h>
> +#include <pci_ids.h>
> +#include <asm/io.h>
> +#include <asm/arch/clock.h>
> +#include <linux/bitfield.h>
> +
> +/*
> + * Octeon II/III (MIPS) have different register offsets than the ARM based
> + * Octeon TX/TX2 SoCs
> + */
> +#if defined(CONFIG_ARCH_OCTEON)
> +#define REG_OFFS		0x0000
> +#else
> +#define REG_OFFS		0x1000
> +#endif
> +
> +#define TWSI_SW_TWSI		(REG_OFFS + 0x00)
> +#define TWSI_TWSI_SW		(REG_OFFS + 0x08)

Is there no clearer name ?

Just wonderung about "TWSI" .. we already have an i2c driver with TWSI defines:

https://gitlab.denx.de/u-boot/u-boot/-/blob/master/drivers/i2c/mvtwsi.c

But it seems they have no common parts.

[...]
> +#if defined(CONFIG_ARCH_OCTEON)
> +static int get_io_clock(void)
> +{
> +	return octeon_get_io_clock();
> +}
> +#else
> +static int get_io_clock(void)
> +{
> +	return octeontx_get_io_clock();
> +}
> +#endif

Here would be good to have the clk framework...

> +
> +static int twsi_thp(void)
> +{
> +	if (IS_ENABLED(CONFIG_ARCH_OCTEON) || IS_ENABLED(CONFIG_ARCH_OCTEONTX))
> +		return 24;
> +	else
> +		return 3;
> +}

May you can add here some comments for this magic numbers?

[...]
> +#define RST_BOOT_PNR_MUL(val)  (((val) >> 33) & 0x1F)

not used define, please remove.

[...]

bye,
Heiko
-- 
DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-52   Fax: +49-8142-66989-80   Email: hs at denx.de

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon
  2020-05-14  7:23 [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon Stefan Roese
  2020-05-19  6:07 ` Heiko Schocher
@ 2020-05-19 12:32 ` Simon Glass
  2020-05-26 10:55   ` Stefan Roese
  2020-06-03  5:15 ` Rayagonda Kokatanur
  2 siblings, 1 reply; 9+ messages in thread
From: Simon Glass @ 2020-05-19 12:32 UTC (permalink / raw)
  To: u-boot

Hi,

On Thu, 14 May 2020 at 01:23, Stefan Roese <sr@denx.de> wrote:
>
> From: Suneel Garapati <sgarapati@marvell.com>
>
> Add support for I2C controllers found on Octeon II/III and Octeon TX
> TX2 SoC platforms.
>
> Signed-off-by: Aaron Williams <awilliams@marvell.com>
> Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
> Signed-off-by: Stefan Roese <sr@denx.de>
> Cc: Heiko Schocher <hs@denx.de>
> Cc: Simon Glass <sjg@chromium.org>
> Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
> Cc: Aaron Williams <awilliams@marvell.com>
> Cc: Chandrakala Chavva <cchavva@marvell.com>
> ---
> RFC -> v1 (Stefan):
> - Separated this patch from the OcteonTX/TX2 RFC patch series into a
>   single patch. This is useful, as the upcoming MIPS Octeon support will
>   use this I2C driver.
> - Added MIPS Octeon II/III support (big endian). Rename driver and its
>   function names from "octeontx" to "octeon" to better match all Octeon
>   platforms.
> - Moved from union to defines / bitmasks as suggested by Simon. This makes
>   the driver usage on little- and big-endian platforms much easier.
> - Enhanced Kconfig text
> - Removed all clock macros (use values from DT)
> - Removed long driver debug strings. This is only available when a debug
>   version of this driver is built. The user / developer can lookup the
>   descriptive error messages in the driver in this case anyway.
> - Removed static "last_id"
> - Dropped misc blank lines. Misc reformatting.
> - Dropped "!= 0"
> - Added missing function comments
> - Added missing strut comments
> - Changed comment style
> - Renames "result" to "ret"
> - Hex numbers uppercase
> - Minor other changes
> - Reword commit text and subject
>
>  drivers/i2c/Kconfig      |  10 +
>  drivers/i2c/Makefile     |   1 +
>  drivers/i2c/octeon_i2c.c | 803 +++++++++++++++++++++++++++++++++++++++
>  3 files changed, 814 insertions(+)
>  create mode 100644 drivers/i2c/octeon_i2c.c
>
> diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
> index e42b6516bf..1330b36698 100644
> --- a/drivers/i2c/Kconfig
> +++ b/drivers/i2c/Kconfig
> @@ -374,6 +374,16 @@ config SYS_I2C_SANDBOX
>           bus. Devices can be attached to the bus using the device tree
>           which specifies the driver to use.  See sandbox.dts as an example.
>
> +config SYS_I2C_OCTEON
> +       bool "Octeon II/III/TX/TX2 I2C driver"
> +       depends on (ARCH_OCTEON || ARCH_OCTEONTX || ARCH_OCTEONTX2) && DM_I2C
> +       default y
> +       help
> +         Add support for the Marvell Octeon I2C driver. This is used with
> +         various Octeon parts such as Octeon II/III and OcteonTX/TX2. All
> +         chips have several I2C ports and all are provided, controlled by
> +         the device tree.
> +
>  config SYS_I2C_S3C24X0
>         bool "Samsung I2C driver"
>         depends on ARCH_EXYNOS4 && DM_I2C
> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
> index 62935b7ebc..2b58aae892 100644
> --- a/drivers/i2c/Makefile
> +++ b/drivers/i2c/Makefile
> @@ -27,6 +27,7 @@ obj-$(CONFIG_SYS_I2C_LPC32XX) += lpc32xx_i2c.o
>  obj-$(CONFIG_SYS_I2C_MESON) += meson_i2c.o
>  obj-$(CONFIG_SYS_I2C_MVTWSI) += mvtwsi.o
>  obj-$(CONFIG_SYS_I2C_MXC) += mxc_i2c.o
> +obj-$(CONFIG_SYS_I2C_OCTEON) += octeon_i2c.o
>  obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
>  obj-$(CONFIG_SYS_I2C_RCAR_I2C) += rcar_i2c.o
>  obj-$(CONFIG_SYS_I2C_RCAR_IIC) += rcar_iic.o
> diff --git a/drivers/i2c/octeon_i2c.c b/drivers/i2c/octeon_i2c.c
> new file mode 100644
> index 0000000000..210f98655e
> --- /dev/null
> +++ b/drivers/i2c/octeon_i2c.c
> @@ -0,0 +1,803 @@
> +// SPDX-License-Identifier:    GPL-2.0
> +/*
> + * Copyright (C) 2018 Marvell International Ltd.
> + */
> +
> +#include <common.h>
> +#include <i2c.h>
> +#include <dm.h>
> +#include <pci_ids.h>
> +#include <asm/io.h>
> +#include <asm/arch/clock.h>
> +#include <linux/bitfield.h>
> +
> +/*
> + * Octeon II/III (MIPS) have different register offsets than the ARM based
> + * Octeon TX/TX2 SoCs
> + */
> +#if defined(CONFIG_ARCH_OCTEON)
> +#define REG_OFFS               0x0000
> +#else
> +#define REG_OFFS               0x1000
> +#endif
> +
> +#define TWSI_SW_TWSI           (REG_OFFS + 0x00)
> +#define TWSI_TWSI_SW           (REG_OFFS + 0x08)
> +#define TWSI_INT               (REG_OFFS + 0x10)
> +#define TWSI_SW_TWSI_EXT       (REG_OFFS + 0x18)
> +
> +#define TWSI_SW_DATA_MASK      GENMASK_ULL(31, 0)
> +#define TWSI_SW_EOP_IA_MASK    GENMASK_ULL(34, 32)
> +#define TWSI_SW_IA_MASK                GENMASK_ULL(39, 35)
> +#define TWSI_SW_ADDR_MASK      GENMASK_ULL(49, 40)
> +#define TWSI_SW_SCR_MASK       GENMASK_ULL(51, 50)
> +#define TWSI_SW_SIZE_MASK      GENMASK_ULL(54, 52)
> +#define TWSI_SW_SOVR           BIT_ULL(55)
> +#define TWSI_SW_R              BIT_ULL(56)
> +#define TWSI_SW_OP_MASK                GENMASK_ULL(60, 57)
> +#define TWSI_SW_EIA            GENMASK_ULL(61)
> +#define TWSI_SW_SLONLY         BIT_ULL(62)
> +#define TWSI_SW_V              BIT_ULL(63)
> +
> +#define TWSI_INT_SDA_OVR       BIT_ULL(8)
> +#define TWSI_INT_SCL_OVR       BIT_ULL(9)
> +#define TWSI_INT_SDA           BIT_ULL(10)
> +#define TWSI_INT_SCL           BIT_ULL(11)
> +
> +enum {
> +       TWSI_OP_WRITE   = 0,
> +       TWSI_OP_READ    = 1,
> +};
> +
> +enum {
> +       TWSI_EOP_SLAVE_ADDR = 0,
> +       TWSI_EOP_CLK_CTL = 3,
> +       TWSI_SW_EOP_IA   = 6,
> +};
> +
> +enum {
> +       TWSI_SLAVEADD     = 0,
> +       TWSI_DATA         = 1,
> +       TWSI_CTL          = 2,
> +       TWSI_CLKCTL       = 3,
> +       TWSI_STAT         = 3,
> +       TWSI_SLAVEADD_EXT = 4,
> +       TWSI_RST          = 7,
> +};
> +
> +enum {
> +       TWSI_CTL_AAK    = BIT(2),
> +       TWSI_CTL_IFLG   = BIT(3),
> +       TWSI_CTL_STP    = BIT(4),
> +       TWSI_CTL_STA    = BIT(5),
> +       TWSI_CTL_ENAB   = BIT(6),
> +       TWSI_CTL_CE     = BIT(7),
> +};
> +
> +/*
> + * Internal errors. When debugging is enabled, the driver will report the
> + * error number and the user / developer can check the table below for the
> + * detailed error description.
> + */
> +enum {
> +       /** Bus error */
> +       TWSI_STAT_BUS_ERROR             = 0x00,
> +       /** Start condition transmitted */
> +       TWSI_STAT_START                 = 0x08,
> +       /** Repeat start condition transmitted */
> +       TWSI_STAT_RSTART                = 0x10,
> +       /** Address + write bit transmitted, ACK received */
> +       TWSI_STAT_TXADDR_ACK            = 0x18,
> +       /** Address + write bit transmitted, /ACK received */
> +       TWSI_STAT_TXADDR_NAK            = 0x20,
> +       /** Data byte transmitted in master mode, ACK received */
> +       TWSI_STAT_TXDATA_ACK            = 0x28,
> +       /** Data byte transmitted in master mode, ACK received */
> +       TWSI_STAT_TXDATA_NAK            = 0x30,
> +       /** Arbitration lost in address or data byte */
> +       TWSI_STAT_TX_ARB_LOST           = 0x38,
> +       /** Address + read bit transmitted, ACK received */
> +       TWSI_STAT_RXADDR_ACK            = 0x40,
> +       /** Address + read bit transmitted, /ACK received */
> +       TWSI_STAT_RXADDR_NAK            = 0x48,
> +       /** Data byte received in master mode, ACK transmitted */
> +       TWSI_STAT_RXDATA_ACK_SENT       = 0x50,
> +       /** Data byte received, NACK transmitted */
> +       TWSI_STAT_RXDATA_NAK_SENT       = 0x58,
> +       /** Slave address received, sent ACK */
> +       TWSI_STAT_SLAVE_RXADDR_ACK      = 0x60,
> +       /**
> +        * Arbitration lost in address as master, slave address + write bit
> +        * received, ACK transmitted
> +        */
> +       TWSI_STAT_TX_ACK_ARB_LOST       = 0x68,
> +       /** General call address received, ACK transmitted */
> +       TWSI_STAT_RX_GEN_ADDR_ACK       = 0x70,
> +       /**
> +        * Arbitration lost in address as master, general call address
> +        * received, ACK transmitted
> +        */
> +       TWSI_STAT_RX_GEN_ADDR_ARB_LOST  = 0x78,
> +       /** Data byte received after slave address received, ACK transmitted */
> +       TWSI_STAT_SLAVE_RXDATA_ACK      = 0x80,
> +       /** Data byte received after slave address received, /ACK transmitted */
> +       TWSI_STAT_SLAVE_RXDATA_NAK      = 0x88,
> +       /**
> +        * Data byte received after general call address received, ACK
> +        * transmitted
> +        */
> +       TWSI_STAT_GEN_RXADDR_ACK        = 0x90,
> +       /**
> +        * Data byte received after general call address received, /ACK
> +        * transmitted
> +        */
> +       TWSI_STAT_GEN_RXADDR_NAK        = 0x98,
> +       /** STOP or repeated START condition received in slave mode */
> +       TWSI_STAT_STOP_MULTI_START      = 0xa0,
> +       /** Slave address + read bit received, ACK transmitted */
> +       TWSI_STAT_SLAVE_RXADDR2_ACK     = 0xa8,
> +       /**
> +        * Arbitration lost in address as master, slave address + read bit
> +        * received, ACK transmitted
> +        */
> +       TWSI_STAT_RXDATA_ACK_ARB_LOST   = 0xb0,
> +       /** Data byte transmitted in slave mode, ACK received */
> +       TWSI_STAT_SLAVE_TXDATA_ACK      = 0xb8,
> +       /** Data byte transmitted in slave mode, /ACK received */
> +       TWSI_STAT_SLAVE_TXDATA_NAK      = 0xc0,
> +       /** Last byte transmitted in slave mode, ACK received */
> +       TWSI_STAT_SLAVE_TXDATA_END_ACK  = 0xc8,
> +       /** Second address byte + write bit transmitted, ACK received */
> +       TWSI_STAT_TXADDR2DATA_ACK       = 0xd0,
> +       /** Second address byte + write bit transmitted, /ACK received */
> +       TWSI_STAT_TXADDR2DATA_NAK       = 0xd8,
> +       /** No relevant status information */
> +       TWSI_STAT_IDLE                  = 0xf8
> +};
> +
> +#ifndef CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR
> +# define CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR      0x77

This should be a device-tree property.

> +#endif
> +
> +/**
> + * struct octeon_twsi - Private data of this driver
> + *
> + * @base:      Base address of i2c registers
> + */
> +struct octeon_twsi {
> +       void __iomem *base;
> +};
> +
> +static void twsi_unblock(void *base);
> +static int twsi_stop(void *base);
> +
> +#if defined(CONFIG_ARCH_OCTEON)

Needs a clock driver.

> +static int get_io_clock(void)
> +{
> +       return octeon_get_io_clock();
> +}
> +#else
> +static int get_io_clock(void)
> +{
> +       return octeontx_get_io_clock();
> +}
> +#endif
> +
> +static int twsi_thp(void)
> +{
> +       if (IS_ENABLED(CONFIG_ARCH_OCTEON) || IS_ENABLED(CONFIG_ARCH_OCTEONTX))
> +               return 24;
> +       else
> +               return 3;
> +}
> +

[..]

> +/**
> + * Calculate the divisor values
> + *
> + * @speed      Speed to set
> + * @m_div      Pointer to M divisor
> + * @n_div      Pointer to N divisor
> + * @return     0 for success, otherwise error
> + */
> +static void twsi_calc_div(unsigned int speed, int *m_div, int *n_div)
> +{
> +       int io_clock_hz;
> +       int tclk, fsamp;
> +       int ndiv, mdiv;
> +
> +#if defined(CONFIG_ARCH_OCTEON) || defined(CONFIG_ARCH_OCTEONTX)
> +       io_clock_hz = get_io_clock();
> +       tclk = io_clock_hz / (2 * (twsi_thp() + 1));
> +#elif defined(CONFIG_ARCH_OCTEONTX2)
> +       /* Refclk src in mode register defaults to 100MHz clock */
> +       io_clock_hz = 100000000; /* 100 Mhz */
> +       tclk = io_clock_hz / (twsi_thp() + 2);
> +#endif

Needs a clock driver. If different logic is needed it should use the
compatible string / driver data rather than #ifdefs.

> +       debug("%s( io_clock %u tclk %u)\n", __func__, io_clock_hz, tclk);
> +
> +       /*
> +        * Compute the clocks M divider:
> +        *
> +        * TWSI freq = (core freq) / (10 x (M+1) x 2 * (thp+1) x 2^N)
> +        * M = ((core freq) / (10 x (TWSI freq) x 2 * (thp+1) x 2^N)) - 1
> +        *
> +        * For OcteonTX2 -
> +        * TWSI freq = (core freq) / (10 x (M+1) x (thp+2) x 2^N)
> +        * M = ((core freq) / (10 x (TWSI freq) x (thp+2) x 2^N)) - 1
> +        */
> +       for (ndiv = 0; ndiv < 8; ndiv++) {
> +               fsamp = tclk / (1 << ndiv);
> +               mdiv = fsamp / speed / 10;
> +               mdiv -= 1;
> +               if (mdiv < 16)
> +                       break;
> +       }
> +
> +       *m_div = mdiv;
> +       *n_div = ndiv;
> +}
> +
> +/**

[..]

> +/**
> + * Driver probe function
> + *
> + * @dev                I2C device to probe
> + * @return     0 for success, otherwise error
> + */
> +static int octeon_pci_i2c_probe(struct udevice *dev)
> +{
> +       struct octeon_twsi *twsi = dev_get_priv(dev);
> +#if !defined(CONFIG_ARCH_OCTEON)

Again should use dev_get_driver_data()

> +       pci_dev_t bdf = dm_pci_get_bdf(dev);
> +
> +       debug("TWSI PCI device: %x\n", bdf);
> +       dev->req_seq = PCI_FUNC(bdf);
> +
> +       twsi->base = dm_pci_map_bar(dev, PCI_BASE_ADDRESS_0,
> +                                   PCI_REGION_MEM);
> +#else
> +       twsi->base = dev_remap_addr(dev);
> +#endif
> +       debug("TWSI bus %d at %p\n", dev->seq, twsi->base);
> +
> +       /* Start with standard speed, real speed set via DT or cmd */
> +       return twsi_init(twsi->base, CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR);
> +}
> +
> +static const struct dm_i2c_ops octeon_i2c_ops = {
> +       .xfer           = octeon_i2c_xfer,
> +       .set_bus_speed  = octeon_i2c_set_bus_speed,
> +};
> +
> +static const struct udevice_id octeon_i2c_ids[] = {
> +       { .compatible = "cavium,thunder-8890-twsi" },
> +       { .compatible = "cavium,octeon-7890-twsi" },
> +       { }
> +};
> +
> +U_BOOT_DRIVER(octeon_pci_twsi) = {
> +       .name   = "i2c_octeon",
> +       .id     = UCLASS_I2C,
> +       .of_match = octeon_i2c_ids,
> +       .probe  = octeon_pci_i2c_probe,
> +       .priv_auto_alloc_size = sizeof(struct octeon_twsi),
> +       .ops    = &octeon_i2c_ops,
> +};
> +
> +#if !defined(CONFIG_ARCH_OCTEON)
> +static struct pci_device_id octeon_twsi_supported[] = {
> +       { PCI_VDEVICE(CAVIUM, PCI_DEVICE_ID_CAVIUM_TWSI) },
> +       { },
> +};
> +
> +U_BOOT_PCI_DEVICE(octeon_pci_twsi, octeon_twsi_supported);
> +#endif
> --
> 2.26.2
>

Regards,
Simon

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon
  2020-05-19  6:07 ` Heiko Schocher
@ 2020-05-26  6:49   ` Stefan Roese
  0 siblings, 0 replies; 9+ messages in thread
From: Stefan Roese @ 2020-05-26  6:49 UTC (permalink / raw)
  To: u-boot

Hi Heiko,

On 19.05.20 08:07, Heiko Schocher wrote:
> Hello Stefan,
> 
> Am 14.05.2020 um 09:23 schrieb Stefan Roese:
>> From: Suneel Garapati <sgarapati@marvell.com>
>>
>> Add support for I2C controllers found on Octeon II/III and Octeon TX
>> TX2 SoC platforms.
>>
>> Signed-off-by: Aaron Williams <awilliams@marvell.com>
>> Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
>> Signed-off-by: Stefan Roese <sr@denx.de>
>> Cc: Heiko Schocher <hs@denx.de>
>> Cc: Simon Glass <sjg@chromium.org>
>> Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
>> Cc: Aaron Williams <awilliams@marvell.com>
>> Cc: Chandrakala Chavva <cchavva@marvell.com>
>> ---
>> RFC -> v1 (Stefan):
>> - Separated this patch from the OcteonTX/TX2 RFC patch series into a
>> ?? single patch. This is useful, as the upcoming MIPS Octeon support will
>> ?? use this I2C driver.
>> - Added MIPS Octeon II/III support (big endian). Rename driver and its
>> ?? function names from "octeontx" to "octeon" to better match all Octeon
>> ?? platforms.
>> - Moved from union to defines / bitmasks as suggested by Simon. This 
>> makes
>> ?? the driver usage on little- and big-endian platforms much easier.
>> - Enhanced Kconfig text
>> - Removed all clock macros (use values from DT)
>> - Removed long driver debug strings. This is only available when a debug
>> ?? version of this driver is built. The user / developer can lookup the
>> ?? descriptive error messages in the driver in this case anyway.
>> - Removed static "last_id"
>> - Dropped misc blank lines. Misc reformatting.
>> - Dropped "!= 0"
>> - Added missing function comments
>> - Added missing strut comments
>> - Changed comment style
>> - Renames "result" to "ret"
>> - Hex numbers uppercase
>> - Minor other changes
>> - Reword commit text and subject
>>
>> ? drivers/i2c/Kconfig????? |? 10 +
>> ? drivers/i2c/Makefile???? |?? 1 +
>> ? drivers/i2c/octeon_i2c.c | 803 +++++++++++++++++++++++++++++++++++++++
>> ? 3 files changed, 814 insertions(+)
>> ? create mode 100644 drivers/i2c/octeon_i2c.c
> 
> nitpick only ...
> 
> Please add a documentation of the device tree bindings.

Okay.

> [...]
>> diff --git a/drivers/i2c/octeon_i2c.c b/drivers/i2c/octeon_i2c.c
>> new file mode 100644
>> index 0000000000..210f98655e
>> --- /dev/null
>> +++ b/drivers/i2c/octeon_i2c.c
>> @@ -0,0 +1,803 @@
>> +// SPDX-License-Identifier:??? GPL-2.0
>> +/*
>> + * Copyright (C) 2018 Marvell International Ltd.
>> + */
>> +
>> +#include <common.h>
>> +#include <i2c.h>
>> +#include <dm.h>
>> +#include <pci_ids.h>
>> +#include <asm/io.h>
>> +#include <asm/arch/clock.h>
>> +#include <linux/bitfield.h>
>> +
>> +/*
>> + * Octeon II/III (MIPS) have different register offsets than the ARM 
>> based
>> + * Octeon TX/TX2 SoCs
>> + */
>> +#if defined(CONFIG_ARCH_OCTEON)
>> +#define REG_OFFS??????? 0x0000
>> +#else
>> +#define REG_OFFS??????? 0x1000
>> +#endif
>> +
>> +#define TWSI_SW_TWSI??????? (REG_OFFS + 0x00)
>> +#define TWSI_TWSI_SW??????? (REG_OFFS + 0x08)
> 
> Is there no clearer name ?
> 
> Just wonderung about "TWSI" .. we already have an i2c driver with TWSI 
> defines:
> 
> https://gitlab.denx.de/u-boot/u-boot/-/blob/master/drivers/i2c/mvtwsi.c
> 
> But it seems they have no common parts.

TWSI is another abbreviation for I2C: Two Wire Serial Interface. I
would like to keep these macros as they reflect the register names in
the Cavium / Marvell manuals.

> [...]
>> +#if defined(CONFIG_ARCH_OCTEON)
>> +static int get_io_clock(void)
>> +{
>> +??? return octeon_get_io_clock();
>> +}
>> +#else
>> +static int get_io_clock(void)
>> +{
>> +??? return octeontx_get_io_clock();
>> +}
>> +#endif
> 
> Here would be good to have the clk framework...

Yes, it would be great. I'm thinking about adding a minimal clk driver
for Octeon - not sure, if I get it done shortly though.

>> +
>> +static int twsi_thp(void)
>> +{
>> +??? if (IS_ENABLED(CONFIG_ARCH_OCTEON) || 
>> IS_ENABLED(CONFIG_ARCH_OCTEONTX))
>> +??????? return 24;
>> +??? else
>> +??????? return 3;
>> +}
> 
> May you can add here some comments for this magic numbers?

I didn't write the initial version of this driver, so its hard for
me to come up with details here. But I'll try.

> [...]
>> +#define RST_BOOT_PNR_MUL(val)? (((val) >> 33) & 0x1F)
> 
> not used define, please remove.

Ah, thanks for spotting.

Thanks,
Stefan

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon
  2020-05-19 12:32 ` Simon Glass
@ 2020-05-26 10:55   ` Stefan Roese
  0 siblings, 0 replies; 9+ messages in thread
From: Stefan Roese @ 2020-05-26 10:55 UTC (permalink / raw)
  To: u-boot

Hi Simon,

On 19.05.20 14:32, Simon Glass wrote:
> Hi,
> 
> On Thu, 14 May 2020 at 01:23, Stefan Roese <sr@denx.de> wrote:
>>
>> From: Suneel Garapati <sgarapati@marvell.com>
>>
>> Add support for I2C controllers found on Octeon II/III and Octeon TX
>> TX2 SoC platforms.
>>
>> Signed-off-by: Aaron Williams <awilliams@marvell.com>
>> Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
>> Signed-off-by: Stefan Roese <sr@denx.de>
>> Cc: Heiko Schocher <hs@denx.de>
>> Cc: Simon Glass <sjg@chromium.org>
>> Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
>> Cc: Aaron Williams <awilliams@marvell.com>
>> Cc: Chandrakala Chavva <cchavva@marvell.com>
>> ---
>> RFC -> v1 (Stefan):
>> - Separated this patch from the OcteonTX/TX2 RFC patch series into a
>>    single patch. This is useful, as the upcoming MIPS Octeon support will
>>    use this I2C driver.
>> - Added MIPS Octeon II/III support (big endian). Rename driver and its
>>    function names from "octeontx" to "octeon" to better match all Octeon
>>    platforms.
>> - Moved from union to defines / bitmasks as suggested by Simon. This makes
>>    the driver usage on little- and big-endian platforms much easier.
>> - Enhanced Kconfig text
>> - Removed all clock macros (use values from DT)
>> - Removed long driver debug strings. This is only available when a debug
>>    version of this driver is built. The user / developer can lookup the
>>    descriptive error messages in the driver in this case anyway.
>> - Removed static "last_id"
>> - Dropped misc blank lines. Misc reformatting.
>> - Dropped "!= 0"
>> - Added missing function comments
>> - Added missing strut comments
>> - Changed comment style
>> - Renames "result" to "ret"
>> - Hex numbers uppercase
>> - Minor other changes
>> - Reword commit text and subject
>>
>>   drivers/i2c/Kconfig      |  10 +
>>   drivers/i2c/Makefile     |   1 +
>>   drivers/i2c/octeon_i2c.c | 803 +++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 814 insertions(+)
>>   create mode 100644 drivers/i2c/octeon_i2c.c
>>
>> diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
>> index e42b6516bf..1330b36698 100644
>> --- a/drivers/i2c/Kconfig
>> +++ b/drivers/i2c/Kconfig
>> @@ -374,6 +374,16 @@ config SYS_I2C_SANDBOX
>>            bus. Devices can be attached to the bus using the device tree
>>            which specifies the driver to use.  See sandbox.dts as an example.
>>
>> +config SYS_I2C_OCTEON
>> +       bool "Octeon II/III/TX/TX2 I2C driver"
>> +       depends on (ARCH_OCTEON || ARCH_OCTEONTX || ARCH_OCTEONTX2) && DM_I2C
>> +       default y
>> +       help
>> +         Add support for the Marvell Octeon I2C driver. This is used with
>> +         various Octeon parts such as Octeon II/III and OcteonTX/TX2. All
>> +         chips have several I2C ports and all are provided, controlled by
>> +         the device tree.
>> +
>>   config SYS_I2C_S3C24X0
>>          bool "Samsung I2C driver"
>>          depends on ARCH_EXYNOS4 && DM_I2C
>> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
>> index 62935b7ebc..2b58aae892 100644
>> --- a/drivers/i2c/Makefile
>> +++ b/drivers/i2c/Makefile
>> @@ -27,6 +27,7 @@ obj-$(CONFIG_SYS_I2C_LPC32XX) += lpc32xx_i2c.o
>>   obj-$(CONFIG_SYS_I2C_MESON) += meson_i2c.o
>>   obj-$(CONFIG_SYS_I2C_MVTWSI) += mvtwsi.o
>>   obj-$(CONFIG_SYS_I2C_MXC) += mxc_i2c.o
>> +obj-$(CONFIG_SYS_I2C_OCTEON) += octeon_i2c.o
>>   obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
>>   obj-$(CONFIG_SYS_I2C_RCAR_I2C) += rcar_i2c.o
>>   obj-$(CONFIG_SYS_I2C_RCAR_IIC) += rcar_iic.o
>> diff --git a/drivers/i2c/octeon_i2c.c b/drivers/i2c/octeon_i2c.c
>> new file mode 100644
>> index 0000000000..210f98655e
>> --- /dev/null
>> +++ b/drivers/i2c/octeon_i2c.c
>> @@ -0,0 +1,803 @@
>> +// SPDX-License-Identifier:    GPL-2.0
>> +/*
>> + * Copyright (C) 2018 Marvell International Ltd.
>> + */
>> +
>> +#include <common.h>
>> +#include <i2c.h>
>> +#include <dm.h>
>> +#include <pci_ids.h>
>> +#include <asm/io.h>
>> +#include <asm/arch/clock.h>
>> +#include <linux/bitfield.h>
>> +
>> +/*
>> + * Octeon II/III (MIPS) have different register offsets than the ARM based
>> + * Octeon TX/TX2 SoCs
>> + */
>> +#if defined(CONFIG_ARCH_OCTEON)
>> +#define REG_OFFS               0x0000
>> +#else
>> +#define REG_OFFS               0x1000
>> +#endif
>> +
>> +#define TWSI_SW_TWSI           (REG_OFFS + 0x00)
>> +#define TWSI_TWSI_SW           (REG_OFFS + 0x08)
>> +#define TWSI_INT               (REG_OFFS + 0x10)
>> +#define TWSI_SW_TWSI_EXT       (REG_OFFS + 0x18)
>> +
>> +#define TWSI_SW_DATA_MASK      GENMASK_ULL(31, 0)
>> +#define TWSI_SW_EOP_IA_MASK    GENMASK_ULL(34, 32)
>> +#define TWSI_SW_IA_MASK                GENMASK_ULL(39, 35)
>> +#define TWSI_SW_ADDR_MASK      GENMASK_ULL(49, 40)
>> +#define TWSI_SW_SCR_MASK       GENMASK_ULL(51, 50)
>> +#define TWSI_SW_SIZE_MASK      GENMASK_ULL(54, 52)
>> +#define TWSI_SW_SOVR           BIT_ULL(55)
>> +#define TWSI_SW_R              BIT_ULL(56)
>> +#define TWSI_SW_OP_MASK                GENMASK_ULL(60, 57)
>> +#define TWSI_SW_EIA            GENMASK_ULL(61)
>> +#define TWSI_SW_SLONLY         BIT_ULL(62)
>> +#define TWSI_SW_V              BIT_ULL(63)
>> +
>> +#define TWSI_INT_SDA_OVR       BIT_ULL(8)
>> +#define TWSI_INT_SCL_OVR       BIT_ULL(9)
>> +#define TWSI_INT_SDA           BIT_ULL(10)
>> +#define TWSI_INT_SCL           BIT_ULL(11)
>> +
>> +enum {
>> +       TWSI_OP_WRITE   = 0,
>> +       TWSI_OP_READ    = 1,
>> +};
>> +
>> +enum {
>> +       TWSI_EOP_SLAVE_ADDR = 0,
>> +       TWSI_EOP_CLK_CTL = 3,
>> +       TWSI_SW_EOP_IA   = 6,
>> +};
>> +
>> +enum {
>> +       TWSI_SLAVEADD     = 0,
>> +       TWSI_DATA         = 1,
>> +       TWSI_CTL          = 2,
>> +       TWSI_CLKCTL       = 3,
>> +       TWSI_STAT         = 3,
>> +       TWSI_SLAVEADD_EXT = 4,
>> +       TWSI_RST          = 7,
>> +};
>> +
>> +enum {
>> +       TWSI_CTL_AAK    = BIT(2),
>> +       TWSI_CTL_IFLG   = BIT(3),
>> +       TWSI_CTL_STP    = BIT(4),
>> +       TWSI_CTL_STA    = BIT(5),
>> +       TWSI_CTL_ENAB   = BIT(6),
>> +       TWSI_CTL_CE     = BIT(7),
>> +};
>> +
>> +/*
>> + * Internal errors. When debugging is enabled, the driver will report the
>> + * error number and the user / developer can check the table below for the
>> + * detailed error description.
>> + */
>> +enum {
>> +       /** Bus error */
>> +       TWSI_STAT_BUS_ERROR             = 0x00,
>> +       /** Start condition transmitted */
>> +       TWSI_STAT_START                 = 0x08,
>> +       /** Repeat start condition transmitted */
>> +       TWSI_STAT_RSTART                = 0x10,
>> +       /** Address + write bit transmitted, ACK received */
>> +       TWSI_STAT_TXADDR_ACK            = 0x18,
>> +       /** Address + write bit transmitted, /ACK received */
>> +       TWSI_STAT_TXADDR_NAK            = 0x20,
>> +       /** Data byte transmitted in master mode, ACK received */
>> +       TWSI_STAT_TXDATA_ACK            = 0x28,
>> +       /** Data byte transmitted in master mode, ACK received */
>> +       TWSI_STAT_TXDATA_NAK            = 0x30,
>> +       /** Arbitration lost in address or data byte */
>> +       TWSI_STAT_TX_ARB_LOST           = 0x38,
>> +       /** Address + read bit transmitted, ACK received */
>> +       TWSI_STAT_RXADDR_ACK            = 0x40,
>> +       /** Address + read bit transmitted, /ACK received */
>> +       TWSI_STAT_RXADDR_NAK            = 0x48,
>> +       /** Data byte received in master mode, ACK transmitted */
>> +       TWSI_STAT_RXDATA_ACK_SENT       = 0x50,
>> +       /** Data byte received, NACK transmitted */
>> +       TWSI_STAT_RXDATA_NAK_SENT       = 0x58,
>> +       /** Slave address received, sent ACK */
>> +       TWSI_STAT_SLAVE_RXADDR_ACK      = 0x60,
>> +       /**
>> +        * Arbitration lost in address as master, slave address + write bit
>> +        * received, ACK transmitted
>> +        */
>> +       TWSI_STAT_TX_ACK_ARB_LOST       = 0x68,
>> +       /** General call address received, ACK transmitted */
>> +       TWSI_STAT_RX_GEN_ADDR_ACK       = 0x70,
>> +       /**
>> +        * Arbitration lost in address as master, general call address
>> +        * received, ACK transmitted
>> +        */
>> +       TWSI_STAT_RX_GEN_ADDR_ARB_LOST  = 0x78,
>> +       /** Data byte received after slave address received, ACK transmitted */
>> +       TWSI_STAT_SLAVE_RXDATA_ACK      = 0x80,
>> +       /** Data byte received after slave address received, /ACK transmitted */
>> +       TWSI_STAT_SLAVE_RXDATA_NAK      = 0x88,
>> +       /**
>> +        * Data byte received after general call address received, ACK
>> +        * transmitted
>> +        */
>> +       TWSI_STAT_GEN_RXADDR_ACK        = 0x90,
>> +       /**
>> +        * Data byte received after general call address received, /ACK
>> +        * transmitted
>> +        */
>> +       TWSI_STAT_GEN_RXADDR_NAK        = 0x98,
>> +       /** STOP or repeated START condition received in slave mode */
>> +       TWSI_STAT_STOP_MULTI_START      = 0xa0,
>> +       /** Slave address + read bit received, ACK transmitted */
>> +       TWSI_STAT_SLAVE_RXADDR2_ACK     = 0xa8,
>> +       /**
>> +        * Arbitration lost in address as master, slave address + read bit
>> +        * received, ACK transmitted
>> +        */
>> +       TWSI_STAT_RXDATA_ACK_ARB_LOST   = 0xb0,
>> +       /** Data byte transmitted in slave mode, ACK received */
>> +       TWSI_STAT_SLAVE_TXDATA_ACK      = 0xb8,
>> +       /** Data byte transmitted in slave mode, /ACK received */
>> +       TWSI_STAT_SLAVE_TXDATA_NAK      = 0xc0,
>> +       /** Last byte transmitted in slave mode, ACK received */
>> +       TWSI_STAT_SLAVE_TXDATA_END_ACK  = 0xc8,
>> +       /** Second address byte + write bit transmitted, ACK received */
>> +       TWSI_STAT_TXADDR2DATA_ACK       = 0xd0,
>> +       /** Second address byte + write bit transmitted, /ACK received */
>> +       TWSI_STAT_TXADDR2DATA_NAK       = 0xd8,
>> +       /** No relevant status information */
>> +       TWSI_STAT_IDLE                  = 0xf8
>> +};
>> +
>> +#ifndef CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR
>> +# define CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR      0x77
> 
> This should be a device-tree property.

Okay, will move to DT.

>> +#endif
>> +
>> +/**
>> + * struct octeon_twsi - Private data of this driver
>> + *
>> + * @base:      Base address of i2c registers
>> + */
>> +struct octeon_twsi {
>> +       void __iomem *base;
>> +};
>> +
>> +static void twsi_unblock(void *base);
>> +static int twsi_stop(void *base);
>> +
>> +#if defined(CONFIG_ARCH_OCTEON)
> 
> Needs a clock driver.

Right. I'll try to add clock driver support with the first Octeon base
port.

>> +static int get_io_clock(void)
>> +{
>> +       return octeon_get_io_clock();
>> +}
>> +#else
>> +static int get_io_clock(void)
>> +{
>> +       return octeontx_get_io_clock();
>> +}
>> +#endif
>> +
>> +static int twsi_thp(void)
>> +{
>> +       if (IS_ENABLED(CONFIG_ARCH_OCTEON) || IS_ENABLED(CONFIG_ARCH_OCTEONTX))
>> +               return 24;
>> +       else
>> +               return 3;
>> +}
>> +
> 
> [..]
> 
>> +/**
>> + * Calculate the divisor values
>> + *
>> + * @speed      Speed to set
>> + * @m_div      Pointer to M divisor
>> + * @n_div      Pointer to N divisor
>> + * @return     0 for success, otherwise error
>> + */
>> +static void twsi_calc_div(unsigned int speed, int *m_div, int *n_div)
>> +{
>> +       int io_clock_hz;
>> +       int tclk, fsamp;
>> +       int ndiv, mdiv;
>> +
>> +#if defined(CONFIG_ARCH_OCTEON) || defined(CONFIG_ARCH_OCTEONTX)
>> +       io_clock_hz = get_io_clock();
>> +       tclk = io_clock_hz / (2 * (twsi_thp() + 1));
>> +#elif defined(CONFIG_ARCH_OCTEONTX2)
>> +       /* Refclk src in mode register defaults to 100MHz clock */
>> +       io_clock_hz = 100000000; /* 100 Mhz */
>> +       tclk = io_clock_hz / (twsi_thp() + 2);
>> +#endif
> 
> Needs a clock driver. If different logic is needed it should use the
> compatible string / driver data rather than #ifdefs.

Yes, will update.

>> +       debug("%s( io_clock %u tclk %u)\n", __func__, io_clock_hz, tclk);
>> +
>> +       /*
>> +        * Compute the clocks M divider:
>> +        *
>> +        * TWSI freq = (core freq) / (10 x (M+1) x 2 * (thp+1) x 2^N)
>> +        * M = ((core freq) / (10 x (TWSI freq) x 2 * (thp+1) x 2^N)) - 1
>> +        *
>> +        * For OcteonTX2 -
>> +        * TWSI freq = (core freq) / (10 x (M+1) x (thp+2) x 2^N)
>> +        * M = ((core freq) / (10 x (TWSI freq) x (thp+2) x 2^N)) - 1
>> +        */
>> +       for (ndiv = 0; ndiv < 8; ndiv++) {
>> +               fsamp = tclk / (1 << ndiv);
>> +               mdiv = fsamp / speed / 10;
>> +               mdiv -= 1;
>> +               if (mdiv < 16)
>> +                       break;
>> +       }
>> +
>> +       *m_div = mdiv;
>> +       *n_div = ndiv;
>> +}
>> +
>> +/**
> 
> [..]
> 
>> +/**
>> + * Driver probe function
>> + *
>> + * @dev                I2C device to probe
>> + * @return     0 for success, otherwise error
>> + */
>> +static int octeon_pci_i2c_probe(struct udevice *dev)
>> +{
>> +       struct octeon_twsi *twsi = dev_get_priv(dev);
>> +#if !defined(CONFIG_ARCH_OCTEON)
> 
> Again should use dev_get_driver_data()

Yes, will update in v2.

Thanks,
Stefan

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon
  2020-05-14  7:23 [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon Stefan Roese
  2020-05-19  6:07 ` Heiko Schocher
  2020-05-19 12:32 ` Simon Glass
@ 2020-06-03  5:15 ` Rayagonda Kokatanur
  2020-06-03  5:20   ` Stefan Roese
  2 siblings, 1 reply; 9+ messages in thread
From: Rayagonda Kokatanur @ 2020-06-03  5:15 UTC (permalink / raw)
  To: u-boot

Hi Stefan,

Few minor comments,

On Thu, May 14, 2020 at 12:53 PM Stefan Roese <sr@denx.de> wrote:
>
> From: Suneel Garapati <sgarapati@marvell.com>
>
> Add support for I2C controllers found on Octeon II/III and Octeon TX
> TX2 SoC platforms.
>
> Signed-off-by: Aaron Williams <awilliams@marvell.com>
> Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
> Signed-off-by: Stefan Roese <sr@denx.de>
> Cc: Heiko Schocher <hs@denx.de>
> Cc: Simon Glass <sjg@chromium.org>
> Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
> Cc: Aaron Williams <awilliams@marvell.com>
> Cc: Chandrakala Chavva <cchavva@marvell.com>
> ---
> RFC -> v1 (Stefan):
> - Separated this patch from the OcteonTX/TX2 RFC patch series into a
>   single patch. This is useful, as the upcoming MIPS Octeon support will
>   use this I2C driver.
> - Added MIPS Octeon II/III support (big endian). Rename driver and its
>   function names from "octeontx" to "octeon" to better match all Octeon
>   platforms.
> - Moved from union to defines / bitmasks as suggested by Simon. This makes
>   the driver usage on little- and big-endian platforms much easier.
> - Enhanced Kconfig text
> - Removed all clock macros (use values from DT)
> - Removed long driver debug strings. This is only available when a debug
>   version of this driver is built. The user / developer can lookup the
>   descriptive error messages in the driver in this case anyway.
> - Removed static "last_id"
> - Dropped misc blank lines. Misc reformatting.
> - Dropped "!= 0"
> - Added missing function comments
> - Added missing strut comments
> - Changed comment style
> - Renames "result" to "ret"
> - Hex numbers uppercase
> - Minor other changes
> - Reword commit text and subject
>
>  drivers/i2c/Kconfig      |  10 +
>  drivers/i2c/Makefile     |   1 +
>  drivers/i2c/octeon_i2c.c | 803 +++++++++++++++++++++++++++++++++++++++
>  3 files changed, 814 insertions(+)
>  create mode 100644 drivers/i2c/octeon_i2c.c
>
> diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
> index e42b6516bf..1330b36698 100644
> --- a/drivers/i2c/Kconfig
> +++ b/drivers/i2c/Kconfig
> @@ -374,6 +374,16 @@ config SYS_I2C_SANDBOX
>           bus. Devices can be attached to the bus using the device tree
>           which specifies the driver to use.  See sandbox.dts as an example.
>
> +config SYS_I2C_OCTEON
> +       bool "Octeon II/III/TX/TX2 I2C driver"
> +       depends on (ARCH_OCTEON || ARCH_OCTEONTX || ARCH_OCTEONTX2) && DM_I2C
> +       default y
> +       help
> +         Add support for the Marvell Octeon I2C driver. This is used with
> +         various Octeon parts such as Octeon II/III and OcteonTX/TX2. All
> +         chips have several I2C ports and all are provided, controlled by
> +         the device tree.
> +
>  config SYS_I2C_S3C24X0
>         bool "Samsung I2C driver"
>         depends on ARCH_EXYNOS4 && DM_I2C
> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
> index 62935b7ebc..2b58aae892 100644
> --- a/drivers/i2c/Makefile
> +++ b/drivers/i2c/Makefile
> @@ -27,6 +27,7 @@ obj-$(CONFIG_SYS_I2C_LPC32XX) += lpc32xx_i2c.o
>  obj-$(CONFIG_SYS_I2C_MESON) += meson_i2c.o
>  obj-$(CONFIG_SYS_I2C_MVTWSI) += mvtwsi.o
>  obj-$(CONFIG_SYS_I2C_MXC) += mxc_i2c.o
> +obj-$(CONFIG_SYS_I2C_OCTEON) += octeon_i2c.o
>  obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
>  obj-$(CONFIG_SYS_I2C_RCAR_I2C) += rcar_i2c.o
>  obj-$(CONFIG_SYS_I2C_RCAR_IIC) += rcar_iic.o
> diff --git a/drivers/i2c/octeon_i2c.c b/drivers/i2c/octeon_i2c.c
> new file mode 100644
> index 0000000000..210f98655e
> --- /dev/null
> +++ b/drivers/i2c/octeon_i2c.c
> @@ -0,0 +1,803 @@
> +// SPDX-License-Identifier:    GPL-2.0
> +/*
> + * Copyright (C) 2018 Marvell International Ltd.

Should it  be 2020 ?
> + */
> +
> +#include <common.h>
> +#include <i2c.h>
> +#include <dm.h>
> +#include <pci_ids.h>
> +#include <asm/io.h>
> +#include <asm/arch/clock.h>
> +#include <linux/bitfield.h>
> +
> +/*
> + * Octeon II/III (MIPS) have different register offsets than the ARM based
> + * Octeon TX/TX2 SoCs
> + */
> +#if defined(CONFIG_ARCH_OCTEON)
> +#define REG_OFFS               0x0000
> +#else
> +#define REG_OFFS               0x1000
> +#endif

How about getting this offset from dt ?
> +
> +#define TWSI_SW_TWSI           (REG_OFFS + 0x00)
> +#define TWSI_TWSI_SW           (REG_OFFS + 0x08)
> +#define TWSI_INT               (REG_OFFS + 0x10)
> +#define TWSI_SW_TWSI_EXT       (REG_OFFS + 0x18)
> +
> +#define TWSI_SW_DATA_MASK      GENMASK_ULL(31, 0)
> +#define TWSI_SW_EOP_IA_MASK    GENMASK_ULL(34, 32)
> +#define TWSI_SW_IA_MASK                GENMASK_ULL(39, 35)
> +#define TWSI_SW_ADDR_MASK      GENMASK_ULL(49, 40)
> +#define TWSI_SW_SCR_MASK       GENMASK_ULL(51, 50)
> +#define TWSI_SW_SIZE_MASK      GENMASK_ULL(54, 52)
> +#define TWSI_SW_SOVR           BIT_ULL(55)
> +#define TWSI_SW_R              BIT_ULL(56)
> +#define TWSI_SW_OP_MASK                GENMASK_ULL(60, 57)
> +#define TWSI_SW_EIA            GENMASK_ULL(61)
> +#define TWSI_SW_SLONLY         BIT_ULL(62)
> +#define TWSI_SW_V              BIT_ULL(63)
> +
> +#define TWSI_INT_SDA_OVR       BIT_ULL(8)
> +#define TWSI_INT_SCL_OVR       BIT_ULL(9)
> +#define TWSI_INT_SDA           BIT_ULL(10)
> +#define TWSI_INT_SCL           BIT_ULL(11)
> +
> +enum {
> +       TWSI_OP_WRITE   = 0,
> +       TWSI_OP_READ    = 1,
> +};
> +
> +enum {
> +       TWSI_EOP_SLAVE_ADDR = 0,
> +       TWSI_EOP_CLK_CTL = 3,
> +       TWSI_SW_EOP_IA   = 6,
> +};
> +
> +enum {
> +       TWSI_SLAVEADD     = 0,
> +       TWSI_DATA         = 1,
> +       TWSI_CTL          = 2,
> +       TWSI_CLKCTL       = 3,
> +       TWSI_STAT         = 3,
> +       TWSI_SLAVEADD_EXT = 4,
> +       TWSI_RST          = 7,
> +};
> +
> +enum {
> +       TWSI_CTL_AAK    = BIT(2),
> +       TWSI_CTL_IFLG   = BIT(3),
> +       TWSI_CTL_STP    = BIT(4),
> +       TWSI_CTL_STA    = BIT(5),
> +       TWSI_CTL_ENAB   = BIT(6),
> +       TWSI_CTL_CE     = BIT(7),
> +};
> +
> +/*
> + * Internal errors. When debugging is enabled, the driver will report the
> + * error number and the user / developer can check the table below for the
> + * detailed error description.
> + */
> +enum {
> +       /** Bus error */
> +       TWSI_STAT_BUS_ERROR             = 0x00,
> +       /** Start condition transmitted */
> +       TWSI_STAT_START                 = 0x08,
> +       /** Repeat start condition transmitted */
> +       TWSI_STAT_RSTART                = 0x10,
> +       /** Address + write bit transmitted, ACK received */
> +       TWSI_STAT_TXADDR_ACK            = 0x18,
> +       /** Address + write bit transmitted, /ACK received */
> +       TWSI_STAT_TXADDR_NAK            = 0x20,
> +       /** Data byte transmitted in master mode, ACK received */
> +       TWSI_STAT_TXDATA_ACK            = 0x28,
> +       /** Data byte transmitted in master mode, ACK received */
> +       TWSI_STAT_TXDATA_NAK            = 0x30,
> +       /** Arbitration lost in address or data byte */
> +       TWSI_STAT_TX_ARB_LOST           = 0x38,
> +       /** Address + read bit transmitted, ACK received */
> +       TWSI_STAT_RXADDR_ACK            = 0x40,
> +       /** Address + read bit transmitted, /ACK received */
> +       TWSI_STAT_RXADDR_NAK            = 0x48,
> +       /** Data byte received in master mode, ACK transmitted */
> +       TWSI_STAT_RXDATA_ACK_SENT       = 0x50,
> +       /** Data byte received, NACK transmitted */
> +       TWSI_STAT_RXDATA_NAK_SENT       = 0x58,
> +       /** Slave address received, sent ACK */
> +       TWSI_STAT_SLAVE_RXADDR_ACK      = 0x60,
> +       /**
> +        * Arbitration lost in address as master, slave address + write bit
> +        * received, ACK transmitted
> +        */
> +       TWSI_STAT_TX_ACK_ARB_LOST       = 0x68,
> +       /** General call address received, ACK transmitted */
> +       TWSI_STAT_RX_GEN_ADDR_ACK       = 0x70,
> +       /**
> +        * Arbitration lost in address as master, general call address
> +        * received, ACK transmitted
> +        */
> +       TWSI_STAT_RX_GEN_ADDR_ARB_LOST  = 0x78,
> +       /** Data byte received after slave address received, ACK transmitted */
> +       TWSI_STAT_SLAVE_RXDATA_ACK      = 0x80,
> +       /** Data byte received after slave address received, /ACK transmitted */
> +       TWSI_STAT_SLAVE_RXDATA_NAK      = 0x88,
> +       /**
> +        * Data byte received after general call address received, ACK
> +        * transmitted
> +        */
> +       TWSI_STAT_GEN_RXADDR_ACK        = 0x90,
> +       /**
> +        * Data byte received after general call address received, /ACK
> +        * transmitted
> +        */
> +       TWSI_STAT_GEN_RXADDR_NAK        = 0x98,
> +       /** STOP or repeated START condition received in slave mode */
> +       TWSI_STAT_STOP_MULTI_START      = 0xa0,
> +       /** Slave address + read bit received, ACK transmitted */
> +       TWSI_STAT_SLAVE_RXADDR2_ACK     = 0xa8,
> +       /**
> +        * Arbitration lost in address as master, slave address + read bit
> +        * received, ACK transmitted
> +        */
> +       TWSI_STAT_RXDATA_ACK_ARB_LOST   = 0xb0,
> +       /** Data byte transmitted in slave mode, ACK received */
> +       TWSI_STAT_SLAVE_TXDATA_ACK      = 0xb8,
> +       /** Data byte transmitted in slave mode, /ACK received */
> +       TWSI_STAT_SLAVE_TXDATA_NAK      = 0xc0,
> +       /** Last byte transmitted in slave mode, ACK received */
> +       TWSI_STAT_SLAVE_TXDATA_END_ACK  = 0xc8,
> +       /** Second address byte + write bit transmitted, ACK received */
> +       TWSI_STAT_TXADDR2DATA_ACK       = 0xd0,
> +       /** Second address byte + write bit transmitted, /ACK received */
> +       TWSI_STAT_TXADDR2DATA_NAK       = 0xd8,
> +       /** No relevant status information */
> +       TWSI_STAT_IDLE                  = 0xf8
> +};
> +
> +#ifndef CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR
> +# define CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR      0x77
> +#endif
> +
> +/**
> + * struct octeon_twsi - Private data of this driver
> + *
> + * @base:      Base address of i2c registers
> + */
> +struct octeon_twsi {
> +       void __iomem *base;
> +};
> +
> +static void twsi_unblock(void *base);
> +static int twsi_stop(void *base);
> +
> +#if defined(CONFIG_ARCH_OCTEON)
> +static int get_io_clock(void)
> +{
> +       return octeon_get_io_clock();
> +}
> +#else
> +static int get_io_clock(void)
> +{
> +       return octeontx_get_io_clock();
> +}
> +#endif
> +
> +static int twsi_thp(void)
> +{
> +       if (IS_ENABLED(CONFIG_ARCH_OCTEON) || IS_ENABLED(CONFIG_ARCH_OCTEONTX))
> +               return 24;
> +       else
> +               return 3;
> +}
> +
> +/**
> + * Returns true if we lost arbitration
> + *
> + * @code       status code
> + * @final_read true if this is the final read operation
> + * @return     true if arbitration has been lost, false if it hasn't been lost.

Instead of true/false, better to mention 0 on success and -ve on failure.
> + */
> +static int twsi_i2c_lost_arb(u8 code, int final_read)
> +{
> +       switch (code) {
> +       case TWSI_STAT_TX_ARB_LOST:
> +       case TWSI_STAT_TX_ACK_ARB_LOST:
> +       case TWSI_STAT_RX_GEN_ADDR_ARB_LOST:
> +       case TWSI_STAT_RXDATA_ACK_ARB_LOST:
> +               /* Arbitration lost */
> +               return -EAGAIN;
> +
> +       case TWSI_STAT_SLAVE_RXADDR_ACK:
> +       case TWSI_STAT_RX_GEN_ADDR_ACK:
> +       case TWSI_STAT_GEN_RXADDR_ACK:
> +       case TWSI_STAT_GEN_RXADDR_NAK:
> +               /* Being addressed as slave, should back off and listen */
> +               return -EIO;
> +
> +       case TWSI_STAT_SLAVE_RXDATA_ACK:
> +       case TWSI_STAT_SLAVE_RXDATA_NAK:
> +       case TWSI_STAT_STOP_MULTI_START:
> +       case TWSI_STAT_SLAVE_RXADDR2_ACK:
> +       case TWSI_STAT_SLAVE_TXDATA_ACK:
> +       case TWSI_STAT_SLAVE_TXDATA_NAK:
> +       case TWSI_STAT_SLAVE_TXDATA_END_ACK:
> +               /* Core busy as slave */
> +               return  -EIO;
> +
> +       case TWSI_STAT_RXDATA_ACK_SENT:
> +               /* Ack allowed on pre-terminal bytes only */
> +               if (!final_read)
> +                       return 0;
> +               return -EAGAIN;
> +
> +       case TWSI_STAT_RXDATA_NAK_SENT:
> +               /* NAK allowed on terminal byte only */
> +               if (!final_read)
> +                       return 0;
> +               return -EAGAIN;
> +
> +       case TWSI_STAT_TXDATA_NAK:
> +       case TWSI_STAT_TXADDR_NAK:
> +       case TWSI_STAT_RXADDR_NAK:
> +       case TWSI_STAT_TXADDR2DATA_NAK:
> +               return -EAGAIN;
> +       }
> +
> +       return 0;
> +}
> +
> +#define RST_BOOT_PNR_MUL(val)  (((val) >> 33) & 0x1F)

Better to move this up where all macros are defined.

> +
> +/**
> + * Writes to the MIO_TWS(0..5)_SW_TWSI register
> + *
> + * @base       Base address of i2c registers
> + * @val                value to write
> + * @return     0 for success, otherwise error
> + */
> +static u64 twsi_write_sw(void __iomem *base, u64 val)
> +{
> +       unsigned long start = get_timer(0);
> +
> +       val &= ~TWSI_SW_R;
> +       val |= TWSI_SW_V;
> +
> +       debug("%s(%p, 0x%llx)\n", __func__, base, val);
> +       writeq(val, base + TWSI_SW_TWSI);
> +       do {
> +               val = readq(base + TWSI_SW_TWSI);
> +       } while ((val & TWSI_SW_V) && (get_timer(start) < 50));
> +
> +       if (val & TWSI_SW_V)
> +               debug("%s: timed out\n", __func__);
> +       return val;

newline before return, please fix globally.
> +}
> +
> +/**
> + * Reads the MIO_TWS(0..5)_SW_TWSI register
> + *
> + * @base       Base address of i2c registers
> + * @val                value for eia and op, etc. to read
> + * @return     value of the register
> + */
> +static u64 twsi_read_sw(void __iomem *base, u64 val)
> +{
> +       unsigned long start = get_timer(0);
> +
> +       val |= TWSI_SW_R | TWSI_SW_V;
> +
> +       debug("%s(%p, 0x%llx)\n", __func__, base, val);
> +       writeq(val, base + TWSI_SW_TWSI);
> +
> +       do {
> +               val = readq(base + TWSI_SW_TWSI);
> +       } while ((val & TWSI_SW_V) && (get_timer(start) < 50));
> +
> +       if (val & TWSI_SW_V)
> +               debug("%s: Error writing 0x%llx\n", __func__, val);
> +
> +       debug("%s: Returning 0x%llx\n", __func__, val);
> +       return val;
> +}
> +
> +/**
> + * Write control register
> + *
> + * @base       Base address for i2c registers
> + * @data       data to write
> + */
> +static void twsi_write_ctl(void __iomem *base, u8 data)
> +{
> +       u64 val;
> +
> +       debug("%s(%p, 0x%x)\n", __func__, base, data);
> +       val = data | FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CTL) |
> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
> +       twsi_write_sw(base, val);
> +}
> +
> +/**
> + * Reads the TWSI Control Register
> + *
> + * @base       Base address for i2c
> + * @return     8-bit TWSI control register
> + */
> +static u8 twsi_read_ctl(void __iomem *base)
> +{
> +       u64 val;
> +
> +       val = FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CTL) |
> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
> +       val = twsi_read_sw(base, val);
> +
> +       debug("%s(%p): 0x%x\n", __func__, base, (u8)val);
> +       return (u8)val;
> +}
> +
> +/**
> + * Read i2c status register
> + *
> + * @base       Base address of i2c registers
> + * @return     value of status register
> + */
> +static u8 twsi_read_status(void __iomem *base)
> +{
> +       u64 val;
> +
> +       val = FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_STAT) |
> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
> +
> +       return twsi_read_sw(base, val);
> +}
> +
> +/**
> + * Waits for an i2c operation to complete
> + *
> + * @param      base    Base address of registers
> + * @return     0 for success, 1 if timeout
> + */
> +static int twsi_wait(void __iomem *base)
> +{
> +       unsigned long start = get_timer(0);
> +       u8 twsi_ctl;
> +
> +       debug("%s(%p)\n", __func__, base);
> +       do {
> +               twsi_ctl = twsi_read_ctl(base);
> +               twsi_ctl &= TWSI_CTL_IFLG;
> +       } while (!twsi_ctl && get_timer(start) < 50);
> +
> +       debug("  return: %u\n", !twsi_ctl);
> +       return !twsi_ctl;
> +}
> +
> +/**
> + * Unsticks the i2c bus
> + *
> + * @base       base address of registers
> + */
> +static int twsi_start_unstick(void __iomem *base)
> +{
> +       twsi_stop(base);
> +       twsi_unblock(base);
> +
> +       return 0;
> +}
> +
> +/**
> + * Sends an i2c start condition
> + *
> + * @base       base address of registers
> + * @return     0 for success, otherwise error
> + */
> +static int twsi_start(void __iomem *base)
> +{
> +       int ret;
> +       u8 stat;
> +
> +       debug("%s(%p)\n", __func__, base);
> +       twsi_write_ctl(base, TWSI_CTL_STA | TWSI_CTL_ENAB);
> +       ret = twsi_wait(base);
> +       if (ret) {
> +               stat = twsi_read_status(base);
> +               debug("%s: ret: 0x%x, status: 0x%x\n", __func__, ret, stat);
> +               switch (stat) {
> +               case TWSI_STAT_START:
> +               case TWSI_STAT_RSTART:
> +                       return 0;
> +               case TWSI_STAT_RXADDR_ACK:
> +               default:
> +                       return twsi_start_unstick(base);
> +               }
> +       }
> +
> +       debug("%s: success\n", __func__);
> +       return 0;
> +}
> +
> +/**
> + * Sends an i2c stop condition
> + *
> + * @base       register base address
> + * @return     0 for success, -1 if error
> + */
> +static int twsi_stop(void __iomem *base)
> +{
> +       u8 stat;
> +
> +       twsi_write_ctl(base, TWSI_CTL_STP | TWSI_CTL_ENAB);
> +
> +       stat = twsi_read_status(base);
> +       if (stat != TWSI_STAT_IDLE) {
> +               debug("%s: Bad status on bus@%p\n", __func__, base);
> +               return -1;
> +       }
> +
> +       return 0;
> +}
> +
> +/**
> + * Writes data to the i2c bus
> + *
> + * @base       register base address
> + * @slave_addr address of slave to write to
> + * @buffer     Pointer to buffer to write
> + * @length     Number of bytes in buffer to write
> + * @return     0 for success, otherwise error
> + */
> +static int twsi_write_data(void __iomem *base, u8  slave_addr,
> +                          u8 *buffer, unsigned int length)

This should be properly aligned.

> +{
> +       unsigned int curr = 0;
> +       u64 val;
> +       int ret;
> +
> +       debug("%s(%p, 0x%x, %p, 0x%x)\n", __func__, base, slave_addr,
> +             buffer, length);

same alignment.

> +       ret = twsi_start(base);
> +       if (ret) {
> +               debug("%s: Could not start BUS transaction\n", __func__);
> +               return -1;
> +       }
> +
> +       ret = twsi_wait(base);
> +       if (ret) {
> +               debug("%s: wait failed\n", __func__);
> +               return ret;
> +       }
> +
> +       val = (u32)(slave_addr << 1) | TWSI_OP_WRITE |
> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
> +       twsi_write_sw(base, val);
> +       twsi_write_ctl(base, TWSI_CTL_ENAB);
> +
> +       debug("%s: Waiting\n", __func__);
> +       ret = twsi_wait(base);
> +       if (ret) {
> +               debug("%s: Timed out writing slave address 0x%x to target\n",
> +                     __func__, slave_addr);
> +               return ret;
> +       }
> +
> +       ret = twsi_read_status(base);
> +       debug("%s: status: 0x%x\n", __func__, ret);
> +       if (ret != TWSI_STAT_TXADDR_ACK) {
> +               debug("%s: status: 0x%x\n", __func__, ret);
> +               twsi_stop(base);
> +               return twsi_i2c_lost_arb(ret, 0);
> +       }
> +
> +       while (curr < length) {
> +               val = buffer[curr++] |
> +                       FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
> +                       FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
> +               twsi_write_sw(base, val);
> +               twsi_write_ctl(base, TWSI_CTL_ENAB);
> +
> +               debug("%s: Writing 0x%llx\n", __func__, val);
> +
> +               ret = twsi_wait(base);
> +               if (ret) {
> +                       debug("%s: Timed out writing data to 0x%x\n",
> +                             __func__, slave_addr);
> +                       return ret;
> +               }
> +               ret = twsi_read_status(base);
> +               debug("%s: status: 0x%x\n", __func__, ret);
> +       }
> +
> +       debug("%s: Stopping\n", __func__);
> +       return twsi_stop(base);
> +}
> +
> +/**
> + * Manually clear the I2C bus and send a stop
> + *
> + * @base       register base address
> + */
> +static void twsi_unblock(void __iomem *base)
> +{
> +       int i;
> +
> +       for (i = 0; i < 9; i++) {
> +               writeq(0, base + TWSI_INT);
> +               udelay(5);
> +               writeq(TWSI_INT_SCL_OVR, base + TWSI_INT);
> +               udelay(5);
> +       }
> +       writeq(TWSI_INT_SCL_OVR | TWSI_INT_SDA_OVR, base + TWSI_INT);
> +       udelay(5);
> +       writeq(TWSI_INT_SDA_OVR, base + TWSI_INT);
> +       udelay(5);
> +       writeq(0, base + TWSI_INT);
> +       udelay(5);
> +}
> +
> +/**
> + * Performs a read transaction on the i2c bus
> + *
> + * @base       Base address of twsi registers
> + * @slave_addr i2c bus address to read from
> + * @buffer     buffer to read into
> + * @length     number of bytes to read
> + * @return     0 for success, otherwise error
> + */
> +static int twsi_read_data(void __iomem *base, u8 slave_addr,
> +                         u8 *buffer, unsigned int length)
> +{
> +       unsigned int curr = 0;
> +       u64 val;
> +       int ret;
> +
> +       debug("%s(%p, 0x%x, %p, %u)\n", __func__, base, slave_addr,
> +             buffer, length);
> +       ret = twsi_start(base);
> +       if (ret) {
> +               debug("%s: start failed\n", __func__);
> +               return ret;
> +       }
> +
> +       ret = twsi_wait(base);
> +       if (ret) {
> +               debug("%s: wait failed\n", __func__);
> +               return ret;
> +       }
> +
> +       val = (u32)(slave_addr << 1) | TWSI_OP_READ |
> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
> +       twsi_write_sw(base, val);
> +       twsi_write_ctl(base, TWSI_CTL_ENAB);
> +
> +       ret = twsi_wait(base);
> +       if (ret) {
> +               debug("%s: waiting for sending addr failed\n", __func__);
> +               return ret;
> +       }
> +
> +       ret = twsi_read_status(base);
> +       debug("%s: status: 0x%x\n", __func__, ret);
> +       if (ret != TWSI_STAT_RXADDR_ACK) {
> +               debug("%s: status: 0x%x\n", __func__, ret);
> +               twsi_stop(base);
> +               return twsi_i2c_lost_arb(ret, 0);
> +       }
> +
> +       while (curr < length) {
> +               twsi_write_ctl(base, TWSI_CTL_ENAB |
> +                              ((curr < length - 1) ? TWSI_CTL_AAK : 0));
> +
> +               ret = twsi_wait(base);
> +               if (ret) {
> +                       debug("%s: waiting for data failed\n", __func__);
> +                       return ret;
> +               }
> +
> +               val = twsi_read_sw(base, val);
> +               buffer[curr++] = (u8)val;
> +       }
> +
> +       twsi_stop(base);
> +
> +       return 0;
> +}
> +
> +/**
> + * Calculate the divisor values
> + *
> + * @speed      Speed to set
> + * @m_div      Pointer to M divisor
> + * @n_div      Pointer to N divisor
> + * @return     0 for success, otherwise error
> + */
> +static void twsi_calc_div(unsigned int speed, int *m_div, int *n_div)
> +{
> +       int io_clock_hz;
> +       int tclk, fsamp;
> +       int ndiv, mdiv;
> +
> +#if defined(CONFIG_ARCH_OCTEON) || defined(CONFIG_ARCH_OCTEONTX)
> +       io_clock_hz = get_io_clock();
> +       tclk = io_clock_hz / (2 * (twsi_thp() + 1));
> +#elif defined(CONFIG_ARCH_OCTEONTX2)
> +       /* Refclk src in mode register defaults to 100MHz clock */
> +       io_clock_hz = 100000000; /* 100 Mhz */
> +       tclk = io_clock_hz / (twsi_thp() + 2);
> +#endif
> +       debug("%s( io_clock %u tclk %u)\n", __func__, io_clock_hz, tclk);
> +
> +       /*
> +        * Compute the clocks M divider:
> +        *
> +        * TWSI freq = (core freq) / (10 x (M+1) x 2 * (thp+1) x 2^N)
> +        * M = ((core freq) / (10 x (TWSI freq) x 2 * (thp+1) x 2^N)) - 1
> +        *
> +        * For OcteonTX2 -
> +        * TWSI freq = (core freq) / (10 x (M+1) x (thp+2) x 2^N)
> +        * M = ((core freq) / (10 x (TWSI freq) x (thp+2) x 2^N)) - 1
> +        */
> +       for (ndiv = 0; ndiv < 8; ndiv++) {
> +               fsamp = tclk / (1 << ndiv);
> +               mdiv = fsamp / speed / 10;
> +               mdiv -= 1;
> +               if (mdiv < 16)
> +                       break;
> +       }
> +
> +       *m_div = mdiv;
> +       *n_div = ndiv;
> +}
> +
> +/**
> + * Init I2C controller
> + *
> + * @base       Base address of twsi registers
> + * @slave_addr I2C slave address to configure this controller to
> + * @return     0 for success, otherwise error
> + */
> +static int twsi_init(void __iomem *base, int slaveaddr)
> +{
> +       u64 val;
> +
> +       debug("%s (%p, 0x%x)\n", __func__, base, slaveaddr);
> +
> +       val = slaveaddr << 1 |
> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, 0) |
> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
> +               TWSI_SW_V;
> +       twsi_write_sw(base, val);
> +
> +       /* Set slave address */
> +       val = slaveaddr |
> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_EOP_SLAVE_ADDR) |
> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
> +               TWSI_SW_V;
> +       twsi_write_sw(base, val);
> +
> +       return 0;
> +}
> +
> +/**
> + * Transfers data over the i2c bus
> + *
> + * @bus                i2c bus to transfer data over
> + * @msg                Array of i2c messages
> + * @nmsgs      Number of messages to send/receive
> + * @return     0 for success, otherwise error
> + */
> +static int octeon_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
> +                          int nmsgs)
> +{
> +       struct octeon_twsi *twsi = dev_get_priv(bus);
> +       int ret;
> +       int i;
> +
> +       debug("%s: %d messages\n", __func__, nmsgs);
> +       for (i = 0; i < nmsgs; i++, msg++) {
> +               debug("%s: chip=0x%x, len=0x%x\n", __func__, msg->addr,
> +                     msg->len);
> +
> +               if (msg->flags & I2C_M_RD) {
> +                       debug("%s: Reading data\n", __func__);
> +                       ret = twsi_read_data(twsi->base, msg->addr,
> +                                            msg->buf, msg->len);
> +               } else {
> +                       debug("%s: Writing data\n", __func__);
> +                       ret = twsi_write_data(twsi->base, msg->addr,
> +                                             msg->buf, msg->len);
> +               }
> +               if (ret) {
> +                       debug("%s: error sending\n", __func__);
> +                       return -EREMOTEIO;
> +               }
> +       }
> +
> +       return 0;
> +}
> +
> +/**
> + * Set I2C bus speed
> + *
> + * @bus                i2c bus to transfer data over
> + * @speed      Speed in Hz to set
> + * @return     0 for success, otherwise error
> + */
> +static int octeon_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
> +{
> +       struct octeon_twsi *twsi = dev_get_priv(bus);
> +       int m_div, n_div;
> +       u64 val;
> +
> +       debug("%s(%p, %u)\n", __func__, bus, speed);
> +
> +       twsi_calc_div(speed, &m_div, &n_div);
> +       if (m_div >= 16)
> +               return -1;
> +
> +       val = (u32)(((m_div & 0xf) << 3) | ((n_div & 0x7) << 0)) |
> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CLKCTL) |
> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
> +               TWSI_SW_V;
> +       /* Only init non-slave ports */
> +       writeq(val, twsi->base + TWSI_SW_TWSI);
> +
> +       debug("%s: Wrote 0x%llx to sw_twsi\n", __func__, val);
> +       return 0;
> +}
> +
> +/**
> + * Driver probe function
> + *
> + * @dev                I2C device to probe
> + * @return     0 for success, otherwise error
> + */
> +static int octeon_pci_i2c_probe(struct udevice *dev)
> +{
> +       struct octeon_twsi *twsi = dev_get_priv(dev);
> +#if !defined(CONFIG_ARCH_OCTEON)
> +       pci_dev_t bdf = dm_pci_get_bdf(dev);
> +
> +       debug("TWSI PCI device: %x\n", bdf);
> +       dev->req_seq = PCI_FUNC(bdf);
> +
> +       twsi->base = dm_pci_map_bar(dev, PCI_BASE_ADDRESS_0,
> +                                   PCI_REGION_MEM);
> +#else
> +       twsi->base = dev_remap_addr(dev);
> +#endif
> +       debug("TWSI bus %d at %p\n", dev->seq, twsi->base);
> +
> +       /* Start with standard speed, real speed set via DT or cmd */
> +       return twsi_init(twsi->base, CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR);
> +}
> +
> +static const struct dm_i2c_ops octeon_i2c_ops = {
> +       .xfer           = octeon_i2c_xfer,
> +       .set_bus_speed  = octeon_i2c_set_bus_speed,
> +};
> +
> +static const struct udevice_id octeon_i2c_ids[] = {
> +       { .compatible = "cavium,thunder-8890-twsi" },
> +       { .compatible = "cavium,octeon-7890-twsi" },
> +       { }
> +};
> +
> +U_BOOT_DRIVER(octeon_pci_twsi) = {
> +       .name   = "i2c_octeon",
> +       .id     = UCLASS_I2C,
> +       .of_match = octeon_i2c_ids,
> +       .probe  = octeon_pci_i2c_probe,
> +       .priv_auto_alloc_size = sizeof(struct octeon_twsi),
> +       .ops    = &octeon_i2c_ops,
> +};
> +
> +#if !defined(CONFIG_ARCH_OCTEON)
> +static struct pci_device_id octeon_twsi_supported[] = {
> +       { PCI_VDEVICE(CAVIUM, PCI_DEVICE_ID_CAVIUM_TWSI) },
> +       { },
> +};
> +
> +U_BOOT_PCI_DEVICE(octeon_pci_twsi, octeon_twsi_supported);
> +#endif
> --
> 2.26.2
>

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon
  2020-06-03  5:15 ` Rayagonda Kokatanur
@ 2020-06-03  5:20   ` Stefan Roese
  2020-06-03  5:37     ` Rayagonda Kokatanur
  0 siblings, 1 reply; 9+ messages in thread
From: Stefan Roese @ 2020-06-03  5:20 UTC (permalink / raw)
  To: u-boot

Hi Rayagonda,

v1 is superseeded. Please review the latest version, v2:

https://patchwork.ozlabs.org/project/uboot/patch/20200526121307.2735-1-sr at denx.de/

Thanks,
Stefan

On 03.06.20 07:15, Rayagonda Kokatanur wrote:
> Hi Stefan,
> 
> Few minor comments,
> 
> On Thu, May 14, 2020 at 12:53 PM Stefan Roese <sr@denx.de> wrote:
>>
>> From: Suneel Garapati <sgarapati@marvell.com>
>>
>> Add support for I2C controllers found on Octeon II/III and Octeon TX
>> TX2 SoC platforms.
>>
>> Signed-off-by: Aaron Williams <awilliams@marvell.com>
>> Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
>> Signed-off-by: Stefan Roese <sr@denx.de>
>> Cc: Heiko Schocher <hs@denx.de>
>> Cc: Simon Glass <sjg@chromium.org>
>> Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
>> Cc: Aaron Williams <awilliams@marvell.com>
>> Cc: Chandrakala Chavva <cchavva@marvell.com>
>> ---
>> RFC -> v1 (Stefan):
>> - Separated this patch from the OcteonTX/TX2 RFC patch series into a
>>    single patch. This is useful, as the upcoming MIPS Octeon support will
>>    use this I2C driver.
>> - Added MIPS Octeon II/III support (big endian). Rename driver and its
>>    function names from "octeontx" to "octeon" to better match all Octeon
>>    platforms.
>> - Moved from union to defines / bitmasks as suggested by Simon. This makes
>>    the driver usage on little- and big-endian platforms much easier.
>> - Enhanced Kconfig text
>> - Removed all clock macros (use values from DT)
>> - Removed long driver debug strings. This is only available when a debug
>>    version of this driver is built. The user / developer can lookup the
>>    descriptive error messages in the driver in this case anyway.
>> - Removed static "last_id"
>> - Dropped misc blank lines. Misc reformatting.
>> - Dropped "!= 0"
>> - Added missing function comments
>> - Added missing strut comments
>> - Changed comment style
>> - Renames "result" to "ret"
>> - Hex numbers uppercase
>> - Minor other changes
>> - Reword commit text and subject
>>
>>   drivers/i2c/Kconfig      |  10 +
>>   drivers/i2c/Makefile     |   1 +
>>   drivers/i2c/octeon_i2c.c | 803 +++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 814 insertions(+)
>>   create mode 100644 drivers/i2c/octeon_i2c.c
>>
>> diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
>> index e42b6516bf..1330b36698 100644
>> --- a/drivers/i2c/Kconfig
>> +++ b/drivers/i2c/Kconfig
>> @@ -374,6 +374,16 @@ config SYS_I2C_SANDBOX
>>            bus. Devices can be attached to the bus using the device tree
>>            which specifies the driver to use.  See sandbox.dts as an example.
>>
>> +config SYS_I2C_OCTEON
>> +       bool "Octeon II/III/TX/TX2 I2C driver"
>> +       depends on (ARCH_OCTEON || ARCH_OCTEONTX || ARCH_OCTEONTX2) && DM_I2C
>> +       default y
>> +       help
>> +         Add support for the Marvell Octeon I2C driver. This is used with
>> +         various Octeon parts such as Octeon II/III and OcteonTX/TX2. All
>> +         chips have several I2C ports and all are provided, controlled by
>> +         the device tree.
>> +
>>   config SYS_I2C_S3C24X0
>>          bool "Samsung I2C driver"
>>          depends on ARCH_EXYNOS4 && DM_I2C
>> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
>> index 62935b7ebc..2b58aae892 100644
>> --- a/drivers/i2c/Makefile
>> +++ b/drivers/i2c/Makefile
>> @@ -27,6 +27,7 @@ obj-$(CONFIG_SYS_I2C_LPC32XX) += lpc32xx_i2c.o
>>   obj-$(CONFIG_SYS_I2C_MESON) += meson_i2c.o
>>   obj-$(CONFIG_SYS_I2C_MVTWSI) += mvtwsi.o
>>   obj-$(CONFIG_SYS_I2C_MXC) += mxc_i2c.o
>> +obj-$(CONFIG_SYS_I2C_OCTEON) += octeon_i2c.o
>>   obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
>>   obj-$(CONFIG_SYS_I2C_RCAR_I2C) += rcar_i2c.o
>>   obj-$(CONFIG_SYS_I2C_RCAR_IIC) += rcar_iic.o
>> diff --git a/drivers/i2c/octeon_i2c.c b/drivers/i2c/octeon_i2c.c
>> new file mode 100644
>> index 0000000000..210f98655e
>> --- /dev/null
>> +++ b/drivers/i2c/octeon_i2c.c
>> @@ -0,0 +1,803 @@
>> +// SPDX-License-Identifier:    GPL-2.0
>> +/*
>> + * Copyright (C) 2018 Marvell International Ltd.
> 
> Should it  be 2020 ?
>> + */
>> +
>> +#include <common.h>
>> +#include <i2c.h>
>> +#include <dm.h>
>> +#include <pci_ids.h>
>> +#include <asm/io.h>
>> +#include <asm/arch/clock.h>
>> +#include <linux/bitfield.h>
>> +
>> +/*
>> + * Octeon II/III (MIPS) have different register offsets than the ARM based
>> + * Octeon TX/TX2 SoCs
>> + */
>> +#if defined(CONFIG_ARCH_OCTEON)
>> +#define REG_OFFS               0x0000
>> +#else
>> +#define REG_OFFS               0x1000
>> +#endif
> 
> How about getting this offset from dt ?
>> +
>> +#define TWSI_SW_TWSI           (REG_OFFS + 0x00)
>> +#define TWSI_TWSI_SW           (REG_OFFS + 0x08)
>> +#define TWSI_INT               (REG_OFFS + 0x10)
>> +#define TWSI_SW_TWSI_EXT       (REG_OFFS + 0x18)
>> +
>> +#define TWSI_SW_DATA_MASK      GENMASK_ULL(31, 0)
>> +#define TWSI_SW_EOP_IA_MASK    GENMASK_ULL(34, 32)
>> +#define TWSI_SW_IA_MASK                GENMASK_ULL(39, 35)
>> +#define TWSI_SW_ADDR_MASK      GENMASK_ULL(49, 40)
>> +#define TWSI_SW_SCR_MASK       GENMASK_ULL(51, 50)
>> +#define TWSI_SW_SIZE_MASK      GENMASK_ULL(54, 52)
>> +#define TWSI_SW_SOVR           BIT_ULL(55)
>> +#define TWSI_SW_R              BIT_ULL(56)
>> +#define TWSI_SW_OP_MASK                GENMASK_ULL(60, 57)
>> +#define TWSI_SW_EIA            GENMASK_ULL(61)
>> +#define TWSI_SW_SLONLY         BIT_ULL(62)
>> +#define TWSI_SW_V              BIT_ULL(63)
>> +
>> +#define TWSI_INT_SDA_OVR       BIT_ULL(8)
>> +#define TWSI_INT_SCL_OVR       BIT_ULL(9)
>> +#define TWSI_INT_SDA           BIT_ULL(10)
>> +#define TWSI_INT_SCL           BIT_ULL(11)
>> +
>> +enum {
>> +       TWSI_OP_WRITE   = 0,
>> +       TWSI_OP_READ    = 1,
>> +};
>> +
>> +enum {
>> +       TWSI_EOP_SLAVE_ADDR = 0,
>> +       TWSI_EOP_CLK_CTL = 3,
>> +       TWSI_SW_EOP_IA   = 6,
>> +};
>> +
>> +enum {
>> +       TWSI_SLAVEADD     = 0,
>> +       TWSI_DATA         = 1,
>> +       TWSI_CTL          = 2,
>> +       TWSI_CLKCTL       = 3,
>> +       TWSI_STAT         = 3,
>> +       TWSI_SLAVEADD_EXT = 4,
>> +       TWSI_RST          = 7,
>> +};
>> +
>> +enum {
>> +       TWSI_CTL_AAK    = BIT(2),
>> +       TWSI_CTL_IFLG   = BIT(3),
>> +       TWSI_CTL_STP    = BIT(4),
>> +       TWSI_CTL_STA    = BIT(5),
>> +       TWSI_CTL_ENAB   = BIT(6),
>> +       TWSI_CTL_CE     = BIT(7),
>> +};
>> +
>> +/*
>> + * Internal errors. When debugging is enabled, the driver will report the
>> + * error number and the user / developer can check the table below for the
>> + * detailed error description.
>> + */
>> +enum {
>> +       /** Bus error */
>> +       TWSI_STAT_BUS_ERROR             = 0x00,
>> +       /** Start condition transmitted */
>> +       TWSI_STAT_START                 = 0x08,
>> +       /** Repeat start condition transmitted */
>> +       TWSI_STAT_RSTART                = 0x10,
>> +       /** Address + write bit transmitted, ACK received */
>> +       TWSI_STAT_TXADDR_ACK            = 0x18,
>> +       /** Address + write bit transmitted, /ACK received */
>> +       TWSI_STAT_TXADDR_NAK            = 0x20,
>> +       /** Data byte transmitted in master mode, ACK received */
>> +       TWSI_STAT_TXDATA_ACK            = 0x28,
>> +       /** Data byte transmitted in master mode, ACK received */
>> +       TWSI_STAT_TXDATA_NAK            = 0x30,
>> +       /** Arbitration lost in address or data byte */
>> +       TWSI_STAT_TX_ARB_LOST           = 0x38,
>> +       /** Address + read bit transmitted, ACK received */
>> +       TWSI_STAT_RXADDR_ACK            = 0x40,
>> +       /** Address + read bit transmitted, /ACK received */
>> +       TWSI_STAT_RXADDR_NAK            = 0x48,
>> +       /** Data byte received in master mode, ACK transmitted */
>> +       TWSI_STAT_RXDATA_ACK_SENT       = 0x50,
>> +       /** Data byte received, NACK transmitted */
>> +       TWSI_STAT_RXDATA_NAK_SENT       = 0x58,
>> +       /** Slave address received, sent ACK */
>> +       TWSI_STAT_SLAVE_RXADDR_ACK      = 0x60,
>> +       /**
>> +        * Arbitration lost in address as master, slave address + write bit
>> +        * received, ACK transmitted
>> +        */
>> +       TWSI_STAT_TX_ACK_ARB_LOST       = 0x68,
>> +       /** General call address received, ACK transmitted */
>> +       TWSI_STAT_RX_GEN_ADDR_ACK       = 0x70,
>> +       /**
>> +        * Arbitration lost in address as master, general call address
>> +        * received, ACK transmitted
>> +        */
>> +       TWSI_STAT_RX_GEN_ADDR_ARB_LOST  = 0x78,
>> +       /** Data byte received after slave address received, ACK transmitted */
>> +       TWSI_STAT_SLAVE_RXDATA_ACK      = 0x80,
>> +       /** Data byte received after slave address received, /ACK transmitted */
>> +       TWSI_STAT_SLAVE_RXDATA_NAK      = 0x88,
>> +       /**
>> +        * Data byte received after general call address received, ACK
>> +        * transmitted
>> +        */
>> +       TWSI_STAT_GEN_RXADDR_ACK        = 0x90,
>> +       /**
>> +        * Data byte received after general call address received, /ACK
>> +        * transmitted
>> +        */
>> +       TWSI_STAT_GEN_RXADDR_NAK        = 0x98,
>> +       /** STOP or repeated START condition received in slave mode */
>> +       TWSI_STAT_STOP_MULTI_START      = 0xa0,
>> +       /** Slave address + read bit received, ACK transmitted */
>> +       TWSI_STAT_SLAVE_RXADDR2_ACK     = 0xa8,
>> +       /**
>> +        * Arbitration lost in address as master, slave address + read bit
>> +        * received, ACK transmitted
>> +        */
>> +       TWSI_STAT_RXDATA_ACK_ARB_LOST   = 0xb0,
>> +       /** Data byte transmitted in slave mode, ACK received */
>> +       TWSI_STAT_SLAVE_TXDATA_ACK      = 0xb8,
>> +       /** Data byte transmitted in slave mode, /ACK received */
>> +       TWSI_STAT_SLAVE_TXDATA_NAK      = 0xc0,
>> +       /** Last byte transmitted in slave mode, ACK received */
>> +       TWSI_STAT_SLAVE_TXDATA_END_ACK  = 0xc8,
>> +       /** Second address byte + write bit transmitted, ACK received */
>> +       TWSI_STAT_TXADDR2DATA_ACK       = 0xd0,
>> +       /** Second address byte + write bit transmitted, /ACK received */
>> +       TWSI_STAT_TXADDR2DATA_NAK       = 0xd8,
>> +       /** No relevant status information */
>> +       TWSI_STAT_IDLE                  = 0xf8
>> +};
>> +
>> +#ifndef CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR
>> +# define CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR      0x77
>> +#endif
>> +
>> +/**
>> + * struct octeon_twsi - Private data of this driver
>> + *
>> + * @base:      Base address of i2c registers
>> + */
>> +struct octeon_twsi {
>> +       void __iomem *base;
>> +};
>> +
>> +static void twsi_unblock(void *base);
>> +static int twsi_stop(void *base);
>> +
>> +#if defined(CONFIG_ARCH_OCTEON)
>> +static int get_io_clock(void)
>> +{
>> +       return octeon_get_io_clock();
>> +}
>> +#else
>> +static int get_io_clock(void)
>> +{
>> +       return octeontx_get_io_clock();
>> +}
>> +#endif
>> +
>> +static int twsi_thp(void)
>> +{
>> +       if (IS_ENABLED(CONFIG_ARCH_OCTEON) || IS_ENABLED(CONFIG_ARCH_OCTEONTX))
>> +               return 24;
>> +       else
>> +               return 3;
>> +}
>> +
>> +/**
>> + * Returns true if we lost arbitration
>> + *
>> + * @code       status code
>> + * @final_read true if this is the final read operation
>> + * @return     true if arbitration has been lost, false if it hasn't been lost.
> 
> Instead of true/false, better to mention 0 on success and -ve on failure.
>> + */
>> +static int twsi_i2c_lost_arb(u8 code, int final_read)
>> +{
>> +       switch (code) {
>> +       case TWSI_STAT_TX_ARB_LOST:
>> +       case TWSI_STAT_TX_ACK_ARB_LOST:
>> +       case TWSI_STAT_RX_GEN_ADDR_ARB_LOST:
>> +       case TWSI_STAT_RXDATA_ACK_ARB_LOST:
>> +               /* Arbitration lost */
>> +               return -EAGAIN;
>> +
>> +       case TWSI_STAT_SLAVE_RXADDR_ACK:
>> +       case TWSI_STAT_RX_GEN_ADDR_ACK:
>> +       case TWSI_STAT_GEN_RXADDR_ACK:
>> +       case TWSI_STAT_GEN_RXADDR_NAK:
>> +               /* Being addressed as slave, should back off and listen */
>> +               return -EIO;
>> +
>> +       case TWSI_STAT_SLAVE_RXDATA_ACK:
>> +       case TWSI_STAT_SLAVE_RXDATA_NAK:
>> +       case TWSI_STAT_STOP_MULTI_START:
>> +       case TWSI_STAT_SLAVE_RXADDR2_ACK:
>> +       case TWSI_STAT_SLAVE_TXDATA_ACK:
>> +       case TWSI_STAT_SLAVE_TXDATA_NAK:
>> +       case TWSI_STAT_SLAVE_TXDATA_END_ACK:
>> +               /* Core busy as slave */
>> +               return  -EIO;
>> +
>> +       case TWSI_STAT_RXDATA_ACK_SENT:
>> +               /* Ack allowed on pre-terminal bytes only */
>> +               if (!final_read)
>> +                       return 0;
>> +               return -EAGAIN;
>> +
>> +       case TWSI_STAT_RXDATA_NAK_SENT:
>> +               /* NAK allowed on terminal byte only */
>> +               if (!final_read)
>> +                       return 0;
>> +               return -EAGAIN;
>> +
>> +       case TWSI_STAT_TXDATA_NAK:
>> +       case TWSI_STAT_TXADDR_NAK:
>> +       case TWSI_STAT_RXADDR_NAK:
>> +       case TWSI_STAT_TXADDR2DATA_NAK:
>> +               return -EAGAIN;
>> +       }
>> +
>> +       return 0;
>> +}
>> +
>> +#define RST_BOOT_PNR_MUL(val)  (((val) >> 33) & 0x1F)
> 
> Better to move this up where all macros are defined.
> 
>> +
>> +/**
>> + * Writes to the MIO_TWS(0..5)_SW_TWSI register
>> + *
>> + * @base       Base address of i2c registers
>> + * @val                value to write
>> + * @return     0 for success, otherwise error
>> + */
>> +static u64 twsi_write_sw(void __iomem *base, u64 val)
>> +{
>> +       unsigned long start = get_timer(0);
>> +
>> +       val &= ~TWSI_SW_R;
>> +       val |= TWSI_SW_V;
>> +
>> +       debug("%s(%p, 0x%llx)\n", __func__, base, val);
>> +       writeq(val, base + TWSI_SW_TWSI);
>> +       do {
>> +               val = readq(base + TWSI_SW_TWSI);
>> +       } while ((val & TWSI_SW_V) && (get_timer(start) < 50));
>> +
>> +       if (val & TWSI_SW_V)
>> +               debug("%s: timed out\n", __func__);
>> +       return val;
> 
> newline before return, please fix globally.
>> +}
>> +
>> +/**
>> + * Reads the MIO_TWS(0..5)_SW_TWSI register
>> + *
>> + * @base       Base address of i2c registers
>> + * @val                value for eia and op, etc. to read
>> + * @return     value of the register
>> + */
>> +static u64 twsi_read_sw(void __iomem *base, u64 val)
>> +{
>> +       unsigned long start = get_timer(0);
>> +
>> +       val |= TWSI_SW_R | TWSI_SW_V;
>> +
>> +       debug("%s(%p, 0x%llx)\n", __func__, base, val);
>> +       writeq(val, base + TWSI_SW_TWSI);
>> +
>> +       do {
>> +               val = readq(base + TWSI_SW_TWSI);
>> +       } while ((val & TWSI_SW_V) && (get_timer(start) < 50));
>> +
>> +       if (val & TWSI_SW_V)
>> +               debug("%s: Error writing 0x%llx\n", __func__, val);
>> +
>> +       debug("%s: Returning 0x%llx\n", __func__, val);
>> +       return val;
>> +}
>> +
>> +/**
>> + * Write control register
>> + *
>> + * @base       Base address for i2c registers
>> + * @data       data to write
>> + */
>> +static void twsi_write_ctl(void __iomem *base, u8 data)
>> +{
>> +       u64 val;
>> +
>> +       debug("%s(%p, 0x%x)\n", __func__, base, data);
>> +       val = data | FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CTL) |
>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
>> +       twsi_write_sw(base, val);
>> +}
>> +
>> +/**
>> + * Reads the TWSI Control Register
>> + *
>> + * @base       Base address for i2c
>> + * @return     8-bit TWSI control register
>> + */
>> +static u8 twsi_read_ctl(void __iomem *base)
>> +{
>> +       u64 val;
>> +
>> +       val = FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CTL) |
>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
>> +       val = twsi_read_sw(base, val);
>> +
>> +       debug("%s(%p): 0x%x\n", __func__, base, (u8)val);
>> +       return (u8)val;
>> +}
>> +
>> +/**
>> + * Read i2c status register
>> + *
>> + * @base       Base address of i2c registers
>> + * @return     value of status register
>> + */
>> +static u8 twsi_read_status(void __iomem *base)
>> +{
>> +       u64 val;
>> +
>> +       val = FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_STAT) |
>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
>> +
>> +       return twsi_read_sw(base, val);
>> +}
>> +
>> +/**
>> + * Waits for an i2c operation to complete
>> + *
>> + * @param      base    Base address of registers
>> + * @return     0 for success, 1 if timeout
>> + */
>> +static int twsi_wait(void __iomem *base)
>> +{
>> +       unsigned long start = get_timer(0);
>> +       u8 twsi_ctl;
>> +
>> +       debug("%s(%p)\n", __func__, base);
>> +       do {
>> +               twsi_ctl = twsi_read_ctl(base);
>> +               twsi_ctl &= TWSI_CTL_IFLG;
>> +       } while (!twsi_ctl && get_timer(start) < 50);
>> +
>> +       debug("  return: %u\n", !twsi_ctl);
>> +       return !twsi_ctl;
>> +}
>> +
>> +/**
>> + * Unsticks the i2c bus
>> + *
>> + * @base       base address of registers
>> + */
>> +static int twsi_start_unstick(void __iomem *base)
>> +{
>> +       twsi_stop(base);
>> +       twsi_unblock(base);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * Sends an i2c start condition
>> + *
>> + * @base       base address of registers
>> + * @return     0 for success, otherwise error
>> + */
>> +static int twsi_start(void __iomem *base)
>> +{
>> +       int ret;
>> +       u8 stat;
>> +
>> +       debug("%s(%p)\n", __func__, base);
>> +       twsi_write_ctl(base, TWSI_CTL_STA | TWSI_CTL_ENAB);
>> +       ret = twsi_wait(base);
>> +       if (ret) {
>> +               stat = twsi_read_status(base);
>> +               debug("%s: ret: 0x%x, status: 0x%x\n", __func__, ret, stat);
>> +               switch (stat) {
>> +               case TWSI_STAT_START:
>> +               case TWSI_STAT_RSTART:
>> +                       return 0;
>> +               case TWSI_STAT_RXADDR_ACK:
>> +               default:
>> +                       return twsi_start_unstick(base);
>> +               }
>> +       }
>> +
>> +       debug("%s: success\n", __func__);
>> +       return 0;
>> +}
>> +
>> +/**
>> + * Sends an i2c stop condition
>> + *
>> + * @base       register base address
>> + * @return     0 for success, -1 if error
>> + */
>> +static int twsi_stop(void __iomem *base)
>> +{
>> +       u8 stat;
>> +
>> +       twsi_write_ctl(base, TWSI_CTL_STP | TWSI_CTL_ENAB);
>> +
>> +       stat = twsi_read_status(base);
>> +       if (stat != TWSI_STAT_IDLE) {
>> +               debug("%s: Bad status on bus@%p\n", __func__, base);
>> +               return -1;
>> +       }
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * Writes data to the i2c bus
>> + *
>> + * @base       register base address
>> + * @slave_addr address of slave to write to
>> + * @buffer     Pointer to buffer to write
>> + * @length     Number of bytes in buffer to write
>> + * @return     0 for success, otherwise error
>> + */
>> +static int twsi_write_data(void __iomem *base, u8  slave_addr,
>> +                          u8 *buffer, unsigned int length)
> 
> This should be properly aligned.
> 
>> +{
>> +       unsigned int curr = 0;
>> +       u64 val;
>> +       int ret;
>> +
>> +       debug("%s(%p, 0x%x, %p, 0x%x)\n", __func__, base, slave_addr,
>> +             buffer, length);
> 
> same alignment.
> 
>> +       ret = twsi_start(base);
>> +       if (ret) {
>> +               debug("%s: Could not start BUS transaction\n", __func__);
>> +               return -1;
>> +       }
>> +
>> +       ret = twsi_wait(base);
>> +       if (ret) {
>> +               debug("%s: wait failed\n", __func__);
>> +               return ret;
>> +       }
>> +
>> +       val = (u32)(slave_addr << 1) | TWSI_OP_WRITE |
>> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
>> +       twsi_write_sw(base, val);
>> +       twsi_write_ctl(base, TWSI_CTL_ENAB);
>> +
>> +       debug("%s: Waiting\n", __func__);
>> +       ret = twsi_wait(base);
>> +       if (ret) {
>> +               debug("%s: Timed out writing slave address 0x%x to target\n",
>> +                     __func__, slave_addr);
>> +               return ret;
>> +       }
>> +
>> +       ret = twsi_read_status(base);
>> +       debug("%s: status: 0x%x\n", __func__, ret);
>> +       if (ret != TWSI_STAT_TXADDR_ACK) {
>> +               debug("%s: status: 0x%x\n", __func__, ret);
>> +               twsi_stop(base);
>> +               return twsi_i2c_lost_arb(ret, 0);
>> +       }
>> +
>> +       while (curr < length) {
>> +               val = buffer[curr++] |
>> +                       FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
>> +                       FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
>> +               twsi_write_sw(base, val);
>> +               twsi_write_ctl(base, TWSI_CTL_ENAB);
>> +
>> +               debug("%s: Writing 0x%llx\n", __func__, val);
>> +
>> +               ret = twsi_wait(base);
>> +               if (ret) {
>> +                       debug("%s: Timed out writing data to 0x%x\n",
>> +                             __func__, slave_addr);
>> +                       return ret;
>> +               }
>> +               ret = twsi_read_status(base);
>> +               debug("%s: status: 0x%x\n", __func__, ret);
>> +       }
>> +
>> +       debug("%s: Stopping\n", __func__);
>> +       return twsi_stop(base);
>> +}
>> +
>> +/**
>> + * Manually clear the I2C bus and send a stop
>> + *
>> + * @base       register base address
>> + */
>> +static void twsi_unblock(void __iomem *base)
>> +{
>> +       int i;
>> +
>> +       for (i = 0; i < 9; i++) {
>> +               writeq(0, base + TWSI_INT);
>> +               udelay(5);
>> +               writeq(TWSI_INT_SCL_OVR, base + TWSI_INT);
>> +               udelay(5);
>> +       }
>> +       writeq(TWSI_INT_SCL_OVR | TWSI_INT_SDA_OVR, base + TWSI_INT);
>> +       udelay(5);
>> +       writeq(TWSI_INT_SDA_OVR, base + TWSI_INT);
>> +       udelay(5);
>> +       writeq(0, base + TWSI_INT);
>> +       udelay(5);
>> +}
>> +
>> +/**
>> + * Performs a read transaction on the i2c bus
>> + *
>> + * @base       Base address of twsi registers
>> + * @slave_addr i2c bus address to read from
>> + * @buffer     buffer to read into
>> + * @length     number of bytes to read
>> + * @return     0 for success, otherwise error
>> + */
>> +static int twsi_read_data(void __iomem *base, u8 slave_addr,
>> +                         u8 *buffer, unsigned int length)
>> +{
>> +       unsigned int curr = 0;
>> +       u64 val;
>> +       int ret;
>> +
>> +       debug("%s(%p, 0x%x, %p, %u)\n", __func__, base, slave_addr,
>> +             buffer, length);
>> +       ret = twsi_start(base);
>> +       if (ret) {
>> +               debug("%s: start failed\n", __func__);
>> +               return ret;
>> +       }
>> +
>> +       ret = twsi_wait(base);
>> +       if (ret) {
>> +               debug("%s: wait failed\n", __func__);
>> +               return ret;
>> +       }
>> +
>> +       val = (u32)(slave_addr << 1) | TWSI_OP_READ |
>> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
>> +       twsi_write_sw(base, val);
>> +       twsi_write_ctl(base, TWSI_CTL_ENAB);
>> +
>> +       ret = twsi_wait(base);
>> +       if (ret) {
>> +               debug("%s: waiting for sending addr failed\n", __func__);
>> +               return ret;
>> +       }
>> +
>> +       ret = twsi_read_status(base);
>> +       debug("%s: status: 0x%x\n", __func__, ret);
>> +       if (ret != TWSI_STAT_RXADDR_ACK) {
>> +               debug("%s: status: 0x%x\n", __func__, ret);
>> +               twsi_stop(base);
>> +               return twsi_i2c_lost_arb(ret, 0);
>> +       }
>> +
>> +       while (curr < length) {
>> +               twsi_write_ctl(base, TWSI_CTL_ENAB |
>> +                              ((curr < length - 1) ? TWSI_CTL_AAK : 0));
>> +
>> +               ret = twsi_wait(base);
>> +               if (ret) {
>> +                       debug("%s: waiting for data failed\n", __func__);
>> +                       return ret;
>> +               }
>> +
>> +               val = twsi_read_sw(base, val);
>> +               buffer[curr++] = (u8)val;
>> +       }
>> +
>> +       twsi_stop(base);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * Calculate the divisor values
>> + *
>> + * @speed      Speed to set
>> + * @m_div      Pointer to M divisor
>> + * @n_div      Pointer to N divisor
>> + * @return     0 for success, otherwise error
>> + */
>> +static void twsi_calc_div(unsigned int speed, int *m_div, int *n_div)
>> +{
>> +       int io_clock_hz;
>> +       int tclk, fsamp;
>> +       int ndiv, mdiv;
>> +
>> +#if defined(CONFIG_ARCH_OCTEON) || defined(CONFIG_ARCH_OCTEONTX)
>> +       io_clock_hz = get_io_clock();
>> +       tclk = io_clock_hz / (2 * (twsi_thp() + 1));
>> +#elif defined(CONFIG_ARCH_OCTEONTX2)
>> +       /* Refclk src in mode register defaults to 100MHz clock */
>> +       io_clock_hz = 100000000; /* 100 Mhz */
>> +       tclk = io_clock_hz / (twsi_thp() + 2);
>> +#endif
>> +       debug("%s( io_clock %u tclk %u)\n", __func__, io_clock_hz, tclk);
>> +
>> +       /*
>> +        * Compute the clocks M divider:
>> +        *
>> +        * TWSI freq = (core freq) / (10 x (M+1) x 2 * (thp+1) x 2^N)
>> +        * M = ((core freq) / (10 x (TWSI freq) x 2 * (thp+1) x 2^N)) - 1
>> +        *
>> +        * For OcteonTX2 -
>> +        * TWSI freq = (core freq) / (10 x (M+1) x (thp+2) x 2^N)
>> +        * M = ((core freq) / (10 x (TWSI freq) x (thp+2) x 2^N)) - 1
>> +        */
>> +       for (ndiv = 0; ndiv < 8; ndiv++) {
>> +               fsamp = tclk / (1 << ndiv);
>> +               mdiv = fsamp / speed / 10;
>> +               mdiv -= 1;
>> +               if (mdiv < 16)
>> +                       break;
>> +       }
>> +
>> +       *m_div = mdiv;
>> +       *n_div = ndiv;
>> +}
>> +
>> +/**
>> + * Init I2C controller
>> + *
>> + * @base       Base address of twsi registers
>> + * @slave_addr I2C slave address to configure this controller to
>> + * @return     0 for success, otherwise error
>> + */
>> +static int twsi_init(void __iomem *base, int slaveaddr)
>> +{
>> +       u64 val;
>> +
>> +       debug("%s (%p, 0x%x)\n", __func__, base, slaveaddr);
>> +
>> +       val = slaveaddr << 1 |
>> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, 0) |
>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
>> +               TWSI_SW_V;
>> +       twsi_write_sw(base, val);
>> +
>> +       /* Set slave address */
>> +       val = slaveaddr |
>> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_EOP_SLAVE_ADDR) |
>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
>> +               TWSI_SW_V;
>> +       twsi_write_sw(base, val);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * Transfers data over the i2c bus
>> + *
>> + * @bus                i2c bus to transfer data over
>> + * @msg                Array of i2c messages
>> + * @nmsgs      Number of messages to send/receive
>> + * @return     0 for success, otherwise error
>> + */
>> +static int octeon_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
>> +                          int nmsgs)
>> +{
>> +       struct octeon_twsi *twsi = dev_get_priv(bus);
>> +       int ret;
>> +       int i;
>> +
>> +       debug("%s: %d messages\n", __func__, nmsgs);
>> +       for (i = 0; i < nmsgs; i++, msg++) {
>> +               debug("%s: chip=0x%x, len=0x%x\n", __func__, msg->addr,
>> +                     msg->len);
>> +
>> +               if (msg->flags & I2C_M_RD) {
>> +                       debug("%s: Reading data\n", __func__);
>> +                       ret = twsi_read_data(twsi->base, msg->addr,
>> +                                            msg->buf, msg->len);
>> +               } else {
>> +                       debug("%s: Writing data\n", __func__);
>> +                       ret = twsi_write_data(twsi->base, msg->addr,
>> +                                             msg->buf, msg->len);
>> +               }
>> +               if (ret) {
>> +                       debug("%s: error sending\n", __func__);
>> +                       return -EREMOTEIO;
>> +               }
>> +       }
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * Set I2C bus speed
>> + *
>> + * @bus                i2c bus to transfer data over
>> + * @speed      Speed in Hz to set
>> + * @return     0 for success, otherwise error
>> + */
>> +static int octeon_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
>> +{
>> +       struct octeon_twsi *twsi = dev_get_priv(bus);
>> +       int m_div, n_div;
>> +       u64 val;
>> +
>> +       debug("%s(%p, %u)\n", __func__, bus, speed);
>> +
>> +       twsi_calc_div(speed, &m_div, &n_div);
>> +       if (m_div >= 16)
>> +               return -1;
>> +
>> +       val = (u32)(((m_div & 0xf) << 3) | ((n_div & 0x7) << 0)) |
>> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CLKCTL) |
>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
>> +               TWSI_SW_V;
>> +       /* Only init non-slave ports */
>> +       writeq(val, twsi->base + TWSI_SW_TWSI);
>> +
>> +       debug("%s: Wrote 0x%llx to sw_twsi\n", __func__, val);
>> +       return 0;
>> +}
>> +
>> +/**
>> + * Driver probe function
>> + *
>> + * @dev                I2C device to probe
>> + * @return     0 for success, otherwise error
>> + */
>> +static int octeon_pci_i2c_probe(struct udevice *dev)
>> +{
>> +       struct octeon_twsi *twsi = dev_get_priv(dev);
>> +#if !defined(CONFIG_ARCH_OCTEON)
>> +       pci_dev_t bdf = dm_pci_get_bdf(dev);
>> +
>> +       debug("TWSI PCI device: %x\n", bdf);
>> +       dev->req_seq = PCI_FUNC(bdf);
>> +
>> +       twsi->base = dm_pci_map_bar(dev, PCI_BASE_ADDRESS_0,
>> +                                   PCI_REGION_MEM);
>> +#else
>> +       twsi->base = dev_remap_addr(dev);
>> +#endif
>> +       debug("TWSI bus %d at %p\n", dev->seq, twsi->base);
>> +
>> +       /* Start with standard speed, real speed set via DT or cmd */
>> +       return twsi_init(twsi->base, CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR);
>> +}
>> +
>> +static const struct dm_i2c_ops octeon_i2c_ops = {
>> +       .xfer           = octeon_i2c_xfer,
>> +       .set_bus_speed  = octeon_i2c_set_bus_speed,
>> +};
>> +
>> +static const struct udevice_id octeon_i2c_ids[] = {
>> +       { .compatible = "cavium,thunder-8890-twsi" },
>> +       { .compatible = "cavium,octeon-7890-twsi" },
>> +       { }
>> +};
>> +
>> +U_BOOT_DRIVER(octeon_pci_twsi) = {
>> +       .name   = "i2c_octeon",
>> +       .id     = UCLASS_I2C,
>> +       .of_match = octeon_i2c_ids,
>> +       .probe  = octeon_pci_i2c_probe,
>> +       .priv_auto_alloc_size = sizeof(struct octeon_twsi),
>> +       .ops    = &octeon_i2c_ops,
>> +};
>> +
>> +#if !defined(CONFIG_ARCH_OCTEON)
>> +static struct pci_device_id octeon_twsi_supported[] = {
>> +       { PCI_VDEVICE(CAVIUM, PCI_DEVICE_ID_CAVIUM_TWSI) },
>> +       { },
>> +};
>> +
>> +U_BOOT_PCI_DEVICE(octeon_pci_twsi, octeon_twsi_supported);
>> +#endif
>> --
>> 2.26.2
>>


Viele Gr??e,
Stefan

-- 
DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-51 Fax: (+49)-8142-66989-80 Email: sr at denx.de

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon
  2020-06-03  5:20   ` Stefan Roese
@ 2020-06-03  5:37     ` Rayagonda Kokatanur
  2020-06-03  5:39       ` Stefan Roese
  0 siblings, 1 reply; 9+ messages in thread
From: Rayagonda Kokatanur @ 2020-06-03  5:37 UTC (permalink / raw)
  To: u-boot

On Wed, Jun 3, 2020 at 10:50 AM Stefan Roese <sr@denx.de> wrote:
>
> Hi Rayagonda,
>
> v1 is superseeded. Please review the latest version, v2:
>
> https://patchwork.ozlabs.org/project/uboot/patch/20200526121307.2735-1-sr at denx.de/

Thank you, I missed that v2.
Anyway please ignore my comments, all of them are fixed in v2.

Thanks,
Rayagonda
>
> Thanks,
> Stefan
>
> On 03.06.20 07:15, Rayagonda Kokatanur wrote:
> > Hi Stefan,
> >
> > Few minor comments,
> >
> > On Thu, May 14, 2020 at 12:53 PM Stefan Roese <sr@denx.de> wrote:
> >>
> >> From: Suneel Garapati <sgarapati@marvell.com>
> >>
> >> Add support for I2C controllers found on Octeon II/III and Octeon TX
> >> TX2 SoC platforms.
> >>
> >> Signed-off-by: Aaron Williams <awilliams@marvell.com>
> >> Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
> >> Signed-off-by: Stefan Roese <sr@denx.de>
> >> Cc: Heiko Schocher <hs@denx.de>
> >> Cc: Simon Glass <sjg@chromium.org>
> >> Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
> >> Cc: Aaron Williams <awilliams@marvell.com>
> >> Cc: Chandrakala Chavva <cchavva@marvell.com>
> >> ---
> >> RFC -> v1 (Stefan):
> >> - Separated this patch from the OcteonTX/TX2 RFC patch series into a
> >>    single patch. This is useful, as the upcoming MIPS Octeon support will
> >>    use this I2C driver.
> >> - Added MIPS Octeon II/III support (big endian). Rename driver and its
> >>    function names from "octeontx" to "octeon" to better match all Octeon
> >>    platforms.
> >> - Moved from union to defines / bitmasks as suggested by Simon. This makes
> >>    the driver usage on little- and big-endian platforms much easier.
> >> - Enhanced Kconfig text
> >> - Removed all clock macros (use values from DT)
> >> - Removed long driver debug strings. This is only available when a debug
> >>    version of this driver is built. The user / developer can lookup the
> >>    descriptive error messages in the driver in this case anyway.
> >> - Removed static "last_id"
> >> - Dropped misc blank lines. Misc reformatting.
> >> - Dropped "!= 0"
> >> - Added missing function comments
> >> - Added missing strut comments
> >> - Changed comment style
> >> - Renames "result" to "ret"
> >> - Hex numbers uppercase
> >> - Minor other changes
> >> - Reword commit text and subject
> >>
> >>   drivers/i2c/Kconfig      |  10 +
> >>   drivers/i2c/Makefile     |   1 +
> >>   drivers/i2c/octeon_i2c.c | 803 +++++++++++++++++++++++++++++++++++++++
> >>   3 files changed, 814 insertions(+)
> >>   create mode 100644 drivers/i2c/octeon_i2c.c
> >>
> >> diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
> >> index e42b6516bf..1330b36698 100644
> >> --- a/drivers/i2c/Kconfig
> >> +++ b/drivers/i2c/Kconfig
> >> @@ -374,6 +374,16 @@ config SYS_I2C_SANDBOX
> >>            bus. Devices can be attached to the bus using the device tree
> >>            which specifies the driver to use.  See sandbox.dts as an example.
> >>
> >> +config SYS_I2C_OCTEON
> >> +       bool "Octeon II/III/TX/TX2 I2C driver"
> >> +       depends on (ARCH_OCTEON || ARCH_OCTEONTX || ARCH_OCTEONTX2) && DM_I2C
> >> +       default y
> >> +       help
> >> +         Add support for the Marvell Octeon I2C driver. This is used with
> >> +         various Octeon parts such as Octeon II/III and OcteonTX/TX2. All
> >> +         chips have several I2C ports and all are provided, controlled by
> >> +         the device tree.
> >> +
> >>   config SYS_I2C_S3C24X0
> >>          bool "Samsung I2C driver"
> >>          depends on ARCH_EXYNOS4 && DM_I2C
> >> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
> >> index 62935b7ebc..2b58aae892 100644
> >> --- a/drivers/i2c/Makefile
> >> +++ b/drivers/i2c/Makefile
> >> @@ -27,6 +27,7 @@ obj-$(CONFIG_SYS_I2C_LPC32XX) += lpc32xx_i2c.o
> >>   obj-$(CONFIG_SYS_I2C_MESON) += meson_i2c.o
> >>   obj-$(CONFIG_SYS_I2C_MVTWSI) += mvtwsi.o
> >>   obj-$(CONFIG_SYS_I2C_MXC) += mxc_i2c.o
> >> +obj-$(CONFIG_SYS_I2C_OCTEON) += octeon_i2c.o
> >>   obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
> >>   obj-$(CONFIG_SYS_I2C_RCAR_I2C) += rcar_i2c.o
> >>   obj-$(CONFIG_SYS_I2C_RCAR_IIC) += rcar_iic.o
> >> diff --git a/drivers/i2c/octeon_i2c.c b/drivers/i2c/octeon_i2c.c
> >> new file mode 100644
> >> index 0000000000..210f98655e
> >> --- /dev/null
> >> +++ b/drivers/i2c/octeon_i2c.c
> >> @@ -0,0 +1,803 @@
> >> +// SPDX-License-Identifier:    GPL-2.0
> >> +/*
> >> + * Copyright (C) 2018 Marvell International Ltd.
> >
> > Should it  be 2020 ?
> >> + */
> >> +
> >> +#include <common.h>
> >> +#include <i2c.h>
> >> +#include <dm.h>
> >> +#include <pci_ids.h>
> >> +#include <asm/io.h>
> >> +#include <asm/arch/clock.h>
> >> +#include <linux/bitfield.h>
> >> +
> >> +/*
> >> + * Octeon II/III (MIPS) have different register offsets than the ARM based
> >> + * Octeon TX/TX2 SoCs
> >> + */
> >> +#if defined(CONFIG_ARCH_OCTEON)
> >> +#define REG_OFFS               0x0000
> >> +#else
> >> +#define REG_OFFS               0x1000
> >> +#endif
> >
> > How about getting this offset from dt ?
> >> +
> >> +#define TWSI_SW_TWSI           (REG_OFFS + 0x00)
> >> +#define TWSI_TWSI_SW           (REG_OFFS + 0x08)
> >> +#define TWSI_INT               (REG_OFFS + 0x10)
> >> +#define TWSI_SW_TWSI_EXT       (REG_OFFS + 0x18)
> >> +
> >> +#define TWSI_SW_DATA_MASK      GENMASK_ULL(31, 0)
> >> +#define TWSI_SW_EOP_IA_MASK    GENMASK_ULL(34, 32)
> >> +#define TWSI_SW_IA_MASK                GENMASK_ULL(39, 35)
> >> +#define TWSI_SW_ADDR_MASK      GENMASK_ULL(49, 40)
> >> +#define TWSI_SW_SCR_MASK       GENMASK_ULL(51, 50)
> >> +#define TWSI_SW_SIZE_MASK      GENMASK_ULL(54, 52)
> >> +#define TWSI_SW_SOVR           BIT_ULL(55)
> >> +#define TWSI_SW_R              BIT_ULL(56)
> >> +#define TWSI_SW_OP_MASK                GENMASK_ULL(60, 57)
> >> +#define TWSI_SW_EIA            GENMASK_ULL(61)
> >> +#define TWSI_SW_SLONLY         BIT_ULL(62)
> >> +#define TWSI_SW_V              BIT_ULL(63)
> >> +
> >> +#define TWSI_INT_SDA_OVR       BIT_ULL(8)
> >> +#define TWSI_INT_SCL_OVR       BIT_ULL(9)
> >> +#define TWSI_INT_SDA           BIT_ULL(10)
> >> +#define TWSI_INT_SCL           BIT_ULL(11)
> >> +
> >> +enum {
> >> +       TWSI_OP_WRITE   = 0,
> >> +       TWSI_OP_READ    = 1,
> >> +};
> >> +
> >> +enum {
> >> +       TWSI_EOP_SLAVE_ADDR = 0,
> >> +       TWSI_EOP_CLK_CTL = 3,
> >> +       TWSI_SW_EOP_IA   = 6,
> >> +};
> >> +
> >> +enum {
> >> +       TWSI_SLAVEADD     = 0,
> >> +       TWSI_DATA         = 1,
> >> +       TWSI_CTL          = 2,
> >> +       TWSI_CLKCTL       = 3,
> >> +       TWSI_STAT         = 3,
> >> +       TWSI_SLAVEADD_EXT = 4,
> >> +       TWSI_RST          = 7,
> >> +};
> >> +
> >> +enum {
> >> +       TWSI_CTL_AAK    = BIT(2),
> >> +       TWSI_CTL_IFLG   = BIT(3),
> >> +       TWSI_CTL_STP    = BIT(4),
> >> +       TWSI_CTL_STA    = BIT(5),
> >> +       TWSI_CTL_ENAB   = BIT(6),
> >> +       TWSI_CTL_CE     = BIT(7),
> >> +};
> >> +
> >> +/*
> >> + * Internal errors. When debugging is enabled, the driver will report the
> >> + * error number and the user / developer can check the table below for the
> >> + * detailed error description.
> >> + */
> >> +enum {
> >> +       /** Bus error */
> >> +       TWSI_STAT_BUS_ERROR             = 0x00,
> >> +       /** Start condition transmitted */
> >> +       TWSI_STAT_START                 = 0x08,
> >> +       /** Repeat start condition transmitted */
> >> +       TWSI_STAT_RSTART                = 0x10,
> >> +       /** Address + write bit transmitted, ACK received */
> >> +       TWSI_STAT_TXADDR_ACK            = 0x18,
> >> +       /** Address + write bit transmitted, /ACK received */
> >> +       TWSI_STAT_TXADDR_NAK            = 0x20,
> >> +       /** Data byte transmitted in master mode, ACK received */
> >> +       TWSI_STAT_TXDATA_ACK            = 0x28,
> >> +       /** Data byte transmitted in master mode, ACK received */
> >> +       TWSI_STAT_TXDATA_NAK            = 0x30,
> >> +       /** Arbitration lost in address or data byte */
> >> +       TWSI_STAT_TX_ARB_LOST           = 0x38,
> >> +       /** Address + read bit transmitted, ACK received */
> >> +       TWSI_STAT_RXADDR_ACK            = 0x40,
> >> +       /** Address + read bit transmitted, /ACK received */
> >> +       TWSI_STAT_RXADDR_NAK            = 0x48,
> >> +       /** Data byte received in master mode, ACK transmitted */
> >> +       TWSI_STAT_RXDATA_ACK_SENT       = 0x50,
> >> +       /** Data byte received, NACK transmitted */
> >> +       TWSI_STAT_RXDATA_NAK_SENT       = 0x58,
> >> +       /** Slave address received, sent ACK */
> >> +       TWSI_STAT_SLAVE_RXADDR_ACK      = 0x60,
> >> +       /**
> >> +        * Arbitration lost in address as master, slave address + write bit
> >> +        * received, ACK transmitted
> >> +        */
> >> +       TWSI_STAT_TX_ACK_ARB_LOST       = 0x68,
> >> +       /** General call address received, ACK transmitted */
> >> +       TWSI_STAT_RX_GEN_ADDR_ACK       = 0x70,
> >> +       /**
> >> +        * Arbitration lost in address as master, general call address
> >> +        * received, ACK transmitted
> >> +        */
> >> +       TWSI_STAT_RX_GEN_ADDR_ARB_LOST  = 0x78,
> >> +       /** Data byte received after slave address received, ACK transmitted */
> >> +       TWSI_STAT_SLAVE_RXDATA_ACK      = 0x80,
> >> +       /** Data byte received after slave address received, /ACK transmitted */
> >> +       TWSI_STAT_SLAVE_RXDATA_NAK      = 0x88,
> >> +       /**
> >> +        * Data byte received after general call address received, ACK
> >> +        * transmitted
> >> +        */
> >> +       TWSI_STAT_GEN_RXADDR_ACK        = 0x90,
> >> +       /**
> >> +        * Data byte received after general call address received, /ACK
> >> +        * transmitted
> >> +        */
> >> +       TWSI_STAT_GEN_RXADDR_NAK        = 0x98,
> >> +       /** STOP or repeated START condition received in slave mode */
> >> +       TWSI_STAT_STOP_MULTI_START      = 0xa0,
> >> +       /** Slave address + read bit received, ACK transmitted */
> >> +       TWSI_STAT_SLAVE_RXADDR2_ACK     = 0xa8,
> >> +       /**
> >> +        * Arbitration lost in address as master, slave address + read bit
> >> +        * received, ACK transmitted
> >> +        */
> >> +       TWSI_STAT_RXDATA_ACK_ARB_LOST   = 0xb0,
> >> +       /** Data byte transmitted in slave mode, ACK received */
> >> +       TWSI_STAT_SLAVE_TXDATA_ACK      = 0xb8,
> >> +       /** Data byte transmitted in slave mode, /ACK received */
> >> +       TWSI_STAT_SLAVE_TXDATA_NAK      = 0xc0,
> >> +       /** Last byte transmitted in slave mode, ACK received */
> >> +       TWSI_STAT_SLAVE_TXDATA_END_ACK  = 0xc8,
> >> +       /** Second address byte + write bit transmitted, ACK received */
> >> +       TWSI_STAT_TXADDR2DATA_ACK       = 0xd0,
> >> +       /** Second address byte + write bit transmitted, /ACK received */
> >> +       TWSI_STAT_TXADDR2DATA_NAK       = 0xd8,
> >> +       /** No relevant status information */
> >> +       TWSI_STAT_IDLE                  = 0xf8
> >> +};
> >> +
> >> +#ifndef CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR
> >> +# define CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR      0x77
> >> +#endif
> >> +
> >> +/**
> >> + * struct octeon_twsi - Private data of this driver
> >> + *
> >> + * @base:      Base address of i2c registers
> >> + */
> >> +struct octeon_twsi {
> >> +       void __iomem *base;
> >> +};
> >> +
> >> +static void twsi_unblock(void *base);
> >> +static int twsi_stop(void *base);
> >> +
> >> +#if defined(CONFIG_ARCH_OCTEON)
> >> +static int get_io_clock(void)
> >> +{
> >> +       return octeon_get_io_clock();
> >> +}
> >> +#else
> >> +static int get_io_clock(void)
> >> +{
> >> +       return octeontx_get_io_clock();
> >> +}
> >> +#endif
> >> +
> >> +static int twsi_thp(void)
> >> +{
> >> +       if (IS_ENABLED(CONFIG_ARCH_OCTEON) || IS_ENABLED(CONFIG_ARCH_OCTEONTX))
> >> +               return 24;
> >> +       else
> >> +               return 3;
> >> +}
> >> +
> >> +/**
> >> + * Returns true if we lost arbitration
> >> + *
> >> + * @code       status code
> >> + * @final_read true if this is the final read operation
> >> + * @return     true if arbitration has been lost, false if it hasn't been lost.
> >
> > Instead of true/false, better to mention 0 on success and -ve on failure.
> >> + */
> >> +static int twsi_i2c_lost_arb(u8 code, int final_read)
> >> +{
> >> +       switch (code) {
> >> +       case TWSI_STAT_TX_ARB_LOST:
> >> +       case TWSI_STAT_TX_ACK_ARB_LOST:
> >> +       case TWSI_STAT_RX_GEN_ADDR_ARB_LOST:
> >> +       case TWSI_STAT_RXDATA_ACK_ARB_LOST:
> >> +               /* Arbitration lost */
> >> +               return -EAGAIN;
> >> +
> >> +       case TWSI_STAT_SLAVE_RXADDR_ACK:
> >> +       case TWSI_STAT_RX_GEN_ADDR_ACK:
> >> +       case TWSI_STAT_GEN_RXADDR_ACK:
> >> +       case TWSI_STAT_GEN_RXADDR_NAK:
> >> +               /* Being addressed as slave, should back off and listen */
> >> +               return -EIO;
> >> +
> >> +       case TWSI_STAT_SLAVE_RXDATA_ACK:
> >> +       case TWSI_STAT_SLAVE_RXDATA_NAK:
> >> +       case TWSI_STAT_STOP_MULTI_START:
> >> +       case TWSI_STAT_SLAVE_RXADDR2_ACK:
> >> +       case TWSI_STAT_SLAVE_TXDATA_ACK:
> >> +       case TWSI_STAT_SLAVE_TXDATA_NAK:
> >> +       case TWSI_STAT_SLAVE_TXDATA_END_ACK:
> >> +               /* Core busy as slave */
> >> +               return  -EIO;
> >> +
> >> +       case TWSI_STAT_RXDATA_ACK_SENT:
> >> +               /* Ack allowed on pre-terminal bytes only */
> >> +               if (!final_read)
> >> +                       return 0;
> >> +               return -EAGAIN;
> >> +
> >> +       case TWSI_STAT_RXDATA_NAK_SENT:
> >> +               /* NAK allowed on terminal byte only */
> >> +               if (!final_read)
> >> +                       return 0;
> >> +               return -EAGAIN;
> >> +
> >> +       case TWSI_STAT_TXDATA_NAK:
> >> +       case TWSI_STAT_TXADDR_NAK:
> >> +       case TWSI_STAT_RXADDR_NAK:
> >> +       case TWSI_STAT_TXADDR2DATA_NAK:
> >> +               return -EAGAIN;
> >> +       }
> >> +
> >> +       return 0;
> >> +}
> >> +
> >> +#define RST_BOOT_PNR_MUL(val)  (((val) >> 33) & 0x1F)
> >
> > Better to move this up where all macros are defined.
> >
> >> +
> >> +/**
> >> + * Writes to the MIO_TWS(0..5)_SW_TWSI register
> >> + *
> >> + * @base       Base address of i2c registers
> >> + * @val                value to write
> >> + * @return     0 for success, otherwise error
> >> + */
> >> +static u64 twsi_write_sw(void __iomem *base, u64 val)
> >> +{
> >> +       unsigned long start = get_timer(0);
> >> +
> >> +       val &= ~TWSI_SW_R;
> >> +       val |= TWSI_SW_V;
> >> +
> >> +       debug("%s(%p, 0x%llx)\n", __func__, base, val);
> >> +       writeq(val, base + TWSI_SW_TWSI);
> >> +       do {
> >> +               val = readq(base + TWSI_SW_TWSI);
> >> +       } while ((val & TWSI_SW_V) && (get_timer(start) < 50));
> >> +
> >> +       if (val & TWSI_SW_V)
> >> +               debug("%s: timed out\n", __func__);
> >> +       return val;
> >
> > newline before return, please fix globally.
> >> +}
> >> +
> >> +/**
> >> + * Reads the MIO_TWS(0..5)_SW_TWSI register
> >> + *
> >> + * @base       Base address of i2c registers
> >> + * @val                value for eia and op, etc. to read
> >> + * @return     value of the register
> >> + */
> >> +static u64 twsi_read_sw(void __iomem *base, u64 val)
> >> +{
> >> +       unsigned long start = get_timer(0);
> >> +
> >> +       val |= TWSI_SW_R | TWSI_SW_V;
> >> +
> >> +       debug("%s(%p, 0x%llx)\n", __func__, base, val);
> >> +       writeq(val, base + TWSI_SW_TWSI);
> >> +
> >> +       do {
> >> +               val = readq(base + TWSI_SW_TWSI);
> >> +       } while ((val & TWSI_SW_V) && (get_timer(start) < 50));
> >> +
> >> +       if (val & TWSI_SW_V)
> >> +               debug("%s: Error writing 0x%llx\n", __func__, val);
> >> +
> >> +       debug("%s: Returning 0x%llx\n", __func__, val);
> >> +       return val;
> >> +}
> >> +
> >> +/**
> >> + * Write control register
> >> + *
> >> + * @base       Base address for i2c registers
> >> + * @data       data to write
> >> + */
> >> +static void twsi_write_ctl(void __iomem *base, u8 data)
> >> +{
> >> +       u64 val;
> >> +
> >> +       debug("%s(%p, 0x%x)\n", __func__, base, data);
> >> +       val = data | FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CTL) |
> >> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
> >> +       twsi_write_sw(base, val);
> >> +}
> >> +
> >> +/**
> >> + * Reads the TWSI Control Register
> >> + *
> >> + * @base       Base address for i2c
> >> + * @return     8-bit TWSI control register
> >> + */
> >> +static u8 twsi_read_ctl(void __iomem *base)
> >> +{
> >> +       u64 val;
> >> +
> >> +       val = FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CTL) |
> >> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
> >> +       val = twsi_read_sw(base, val);
> >> +
> >> +       debug("%s(%p): 0x%x\n", __func__, base, (u8)val);
> >> +       return (u8)val;
> >> +}
> >> +
> >> +/**
> >> + * Read i2c status register
> >> + *
> >> + * @base       Base address of i2c registers
> >> + * @return     value of status register
> >> + */
> >> +static u8 twsi_read_status(void __iomem *base)
> >> +{
> >> +       u64 val;
> >> +
> >> +       val = FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_STAT) |
> >> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
> >> +
> >> +       return twsi_read_sw(base, val);
> >> +}
> >> +
> >> +/**
> >> + * Waits for an i2c operation to complete
> >> + *
> >> + * @param      base    Base address of registers
> >> + * @return     0 for success, 1 if timeout
> >> + */
> >> +static int twsi_wait(void __iomem *base)
> >> +{
> >> +       unsigned long start = get_timer(0);
> >> +       u8 twsi_ctl;
> >> +
> >> +       debug("%s(%p)\n", __func__, base);
> >> +       do {
> >> +               twsi_ctl = twsi_read_ctl(base);
> >> +               twsi_ctl &= TWSI_CTL_IFLG;
> >> +       } while (!twsi_ctl && get_timer(start) < 50);
> >> +
> >> +       debug("  return: %u\n", !twsi_ctl);
> >> +       return !twsi_ctl;
> >> +}
> >> +
> >> +/**
> >> + * Unsticks the i2c bus
> >> + *
> >> + * @base       base address of registers
> >> + */
> >> +static int twsi_start_unstick(void __iomem *base)
> >> +{
> >> +       twsi_stop(base);
> >> +       twsi_unblock(base);
> >> +
> >> +       return 0;
> >> +}
> >> +
> >> +/**
> >> + * Sends an i2c start condition
> >> + *
> >> + * @base       base address of registers
> >> + * @return     0 for success, otherwise error
> >> + */
> >> +static int twsi_start(void __iomem *base)
> >> +{
> >> +       int ret;
> >> +       u8 stat;
> >> +
> >> +       debug("%s(%p)\n", __func__, base);
> >> +       twsi_write_ctl(base, TWSI_CTL_STA | TWSI_CTL_ENAB);
> >> +       ret = twsi_wait(base);
> >> +       if (ret) {
> >> +               stat = twsi_read_status(base);
> >> +               debug("%s: ret: 0x%x, status: 0x%x\n", __func__, ret, stat);
> >> +               switch (stat) {
> >> +               case TWSI_STAT_START:
> >> +               case TWSI_STAT_RSTART:
> >> +                       return 0;
> >> +               case TWSI_STAT_RXADDR_ACK:
> >> +               default:
> >> +                       return twsi_start_unstick(base);
> >> +               }
> >> +       }
> >> +
> >> +       debug("%s: success\n", __func__);
> >> +       return 0;
> >> +}
> >> +
> >> +/**
> >> + * Sends an i2c stop condition
> >> + *
> >> + * @base       register base address
> >> + * @return     0 for success, -1 if error
> >> + */
> >> +static int twsi_stop(void __iomem *base)
> >> +{
> >> +       u8 stat;
> >> +
> >> +       twsi_write_ctl(base, TWSI_CTL_STP | TWSI_CTL_ENAB);
> >> +
> >> +       stat = twsi_read_status(base);
> >> +       if (stat != TWSI_STAT_IDLE) {
> >> +               debug("%s: Bad status on bus@%p\n", __func__, base);
> >> +               return -1;
> >> +       }
> >> +
> >> +       return 0;
> >> +}
> >> +
> >> +/**
> >> + * Writes data to the i2c bus
> >> + *
> >> + * @base       register base address
> >> + * @slave_addr address of slave to write to
> >> + * @buffer     Pointer to buffer to write
> >> + * @length     Number of bytes in buffer to write
> >> + * @return     0 for success, otherwise error
> >> + */
> >> +static int twsi_write_data(void __iomem *base, u8  slave_addr,
> >> +                          u8 *buffer, unsigned int length)
> >
> > This should be properly aligned.
> >
> >> +{
> >> +       unsigned int curr = 0;
> >> +       u64 val;
> >> +       int ret;
> >> +
> >> +       debug("%s(%p, 0x%x, %p, 0x%x)\n", __func__, base, slave_addr,
> >> +             buffer, length);
> >
> > same alignment.
> >
> >> +       ret = twsi_start(base);
> >> +       if (ret) {
> >> +               debug("%s: Could not start BUS transaction\n", __func__);
> >> +               return -1;
> >> +       }
> >> +
> >> +       ret = twsi_wait(base);
> >> +       if (ret) {
> >> +               debug("%s: wait failed\n", __func__);
> >> +               return ret;
> >> +       }
> >> +
> >> +       val = (u32)(slave_addr << 1) | TWSI_OP_WRITE |
> >> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
> >> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
> >> +       twsi_write_sw(base, val);
> >> +       twsi_write_ctl(base, TWSI_CTL_ENAB);
> >> +
> >> +       debug("%s: Waiting\n", __func__);
> >> +       ret = twsi_wait(base);
> >> +       if (ret) {
> >> +               debug("%s: Timed out writing slave address 0x%x to target\n",
> >> +                     __func__, slave_addr);
> >> +               return ret;
> >> +       }
> >> +
> >> +       ret = twsi_read_status(base);
> >> +       debug("%s: status: 0x%x\n", __func__, ret);
> >> +       if (ret != TWSI_STAT_TXADDR_ACK) {
> >> +               debug("%s: status: 0x%x\n", __func__, ret);
> >> +               twsi_stop(base);
> >> +               return twsi_i2c_lost_arb(ret, 0);
> >> +       }
> >> +
> >> +       while (curr < length) {
> >> +               val = buffer[curr++] |
> >> +                       FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
> >> +                       FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
> >> +               twsi_write_sw(base, val);
> >> +               twsi_write_ctl(base, TWSI_CTL_ENAB);
> >> +
> >> +               debug("%s: Writing 0x%llx\n", __func__, val);
> >> +
> >> +               ret = twsi_wait(base);
> >> +               if (ret) {
> >> +                       debug("%s: Timed out writing data to 0x%x\n",
> >> +                             __func__, slave_addr);
> >> +                       return ret;
> >> +               }
> >> +               ret = twsi_read_status(base);
> >> +               debug("%s: status: 0x%x\n", __func__, ret);
> >> +       }
> >> +
> >> +       debug("%s: Stopping\n", __func__);
> >> +       return twsi_stop(base);
> >> +}
> >> +
> >> +/**
> >> + * Manually clear the I2C bus and send a stop
> >> + *
> >> + * @base       register base address
> >> + */
> >> +static void twsi_unblock(void __iomem *base)
> >> +{
> >> +       int i;
> >> +
> >> +       for (i = 0; i < 9; i++) {
> >> +               writeq(0, base + TWSI_INT);
> >> +               udelay(5);
> >> +               writeq(TWSI_INT_SCL_OVR, base + TWSI_INT);
> >> +               udelay(5);
> >> +       }
> >> +       writeq(TWSI_INT_SCL_OVR | TWSI_INT_SDA_OVR, base + TWSI_INT);
> >> +       udelay(5);
> >> +       writeq(TWSI_INT_SDA_OVR, base + TWSI_INT);
> >> +       udelay(5);
> >> +       writeq(0, base + TWSI_INT);
> >> +       udelay(5);
> >> +}
> >> +
> >> +/**
> >> + * Performs a read transaction on the i2c bus
> >> + *
> >> + * @base       Base address of twsi registers
> >> + * @slave_addr i2c bus address to read from
> >> + * @buffer     buffer to read into
> >> + * @length     number of bytes to read
> >> + * @return     0 for success, otherwise error
> >> + */
> >> +static int twsi_read_data(void __iomem *base, u8 slave_addr,
> >> +                         u8 *buffer, unsigned int length)
> >> +{
> >> +       unsigned int curr = 0;
> >> +       u64 val;
> >> +       int ret;
> >> +
> >> +       debug("%s(%p, 0x%x, %p, %u)\n", __func__, base, slave_addr,
> >> +             buffer, length);
> >> +       ret = twsi_start(base);
> >> +       if (ret) {
> >> +               debug("%s: start failed\n", __func__);
> >> +               return ret;
> >> +       }
> >> +
> >> +       ret = twsi_wait(base);
> >> +       if (ret) {
> >> +               debug("%s: wait failed\n", __func__);
> >> +               return ret;
> >> +       }
> >> +
> >> +       val = (u32)(slave_addr << 1) | TWSI_OP_READ |
> >> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
> >> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
> >> +       twsi_write_sw(base, val);
> >> +       twsi_write_ctl(base, TWSI_CTL_ENAB);
> >> +
> >> +       ret = twsi_wait(base);
> >> +       if (ret) {
> >> +               debug("%s: waiting for sending addr failed\n", __func__);
> >> +               return ret;
> >> +       }
> >> +
> >> +       ret = twsi_read_status(base);
> >> +       debug("%s: status: 0x%x\n", __func__, ret);
> >> +       if (ret != TWSI_STAT_RXADDR_ACK) {
> >> +               debug("%s: status: 0x%x\n", __func__, ret);
> >> +               twsi_stop(base);
> >> +               return twsi_i2c_lost_arb(ret, 0);
> >> +       }
> >> +
> >> +       while (curr < length) {
> >> +               twsi_write_ctl(base, TWSI_CTL_ENAB |
> >> +                              ((curr < length - 1) ? TWSI_CTL_AAK : 0));
> >> +
> >> +               ret = twsi_wait(base);
> >> +               if (ret) {
> >> +                       debug("%s: waiting for data failed\n", __func__);
> >> +                       return ret;
> >> +               }
> >> +
> >> +               val = twsi_read_sw(base, val);
> >> +               buffer[curr++] = (u8)val;
> >> +       }
> >> +
> >> +       twsi_stop(base);
> >> +
> >> +       return 0;
> >> +}
> >> +
> >> +/**
> >> + * Calculate the divisor values
> >> + *
> >> + * @speed      Speed to set
> >> + * @m_div      Pointer to M divisor
> >> + * @n_div      Pointer to N divisor
> >> + * @return     0 for success, otherwise error
> >> + */
> >> +static void twsi_calc_div(unsigned int speed, int *m_div, int *n_div)
> >> +{
> >> +       int io_clock_hz;
> >> +       int tclk, fsamp;
> >> +       int ndiv, mdiv;
> >> +
> >> +#if defined(CONFIG_ARCH_OCTEON) || defined(CONFIG_ARCH_OCTEONTX)
> >> +       io_clock_hz = get_io_clock();
> >> +       tclk = io_clock_hz / (2 * (twsi_thp() + 1));
> >> +#elif defined(CONFIG_ARCH_OCTEONTX2)
> >> +       /* Refclk src in mode register defaults to 100MHz clock */
> >> +       io_clock_hz = 100000000; /* 100 Mhz */
> >> +       tclk = io_clock_hz / (twsi_thp() + 2);
> >> +#endif
> >> +       debug("%s( io_clock %u tclk %u)\n", __func__, io_clock_hz, tclk);
> >> +
> >> +       /*
> >> +        * Compute the clocks M divider:
> >> +        *
> >> +        * TWSI freq = (core freq) / (10 x (M+1) x 2 * (thp+1) x 2^N)
> >> +        * M = ((core freq) / (10 x (TWSI freq) x 2 * (thp+1) x 2^N)) - 1
> >> +        *
> >> +        * For OcteonTX2 -
> >> +        * TWSI freq = (core freq) / (10 x (M+1) x (thp+2) x 2^N)
> >> +        * M = ((core freq) / (10 x (TWSI freq) x (thp+2) x 2^N)) - 1
> >> +        */
> >> +       for (ndiv = 0; ndiv < 8; ndiv++) {
> >> +               fsamp = tclk / (1 << ndiv);
> >> +               mdiv = fsamp / speed / 10;
> >> +               mdiv -= 1;
> >> +               if (mdiv < 16)
> >> +                       break;
> >> +       }
> >> +
> >> +       *m_div = mdiv;
> >> +       *n_div = ndiv;
> >> +}
> >> +
> >> +/**
> >> + * Init I2C controller
> >> + *
> >> + * @base       Base address of twsi registers
> >> + * @slave_addr I2C slave address to configure this controller to
> >> + * @return     0 for success, otherwise error
> >> + */
> >> +static int twsi_init(void __iomem *base, int slaveaddr)
> >> +{
> >> +       u64 val;
> >> +
> >> +       debug("%s (%p, 0x%x)\n", __func__, base, slaveaddr);
> >> +
> >> +       val = slaveaddr << 1 |
> >> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, 0) |
> >> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
> >> +               TWSI_SW_V;
> >> +       twsi_write_sw(base, val);
> >> +
> >> +       /* Set slave address */
> >> +       val = slaveaddr |
> >> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_EOP_SLAVE_ADDR) |
> >> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
> >> +               TWSI_SW_V;
> >> +       twsi_write_sw(base, val);
> >> +
> >> +       return 0;
> >> +}
> >> +
> >> +/**
> >> + * Transfers data over the i2c bus
> >> + *
> >> + * @bus                i2c bus to transfer data over
> >> + * @msg                Array of i2c messages
> >> + * @nmsgs      Number of messages to send/receive
> >> + * @return     0 for success, otherwise error
> >> + */
> >> +static int octeon_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
> >> +                          int nmsgs)
> >> +{
> >> +       struct octeon_twsi *twsi = dev_get_priv(bus);
> >> +       int ret;
> >> +       int i;
> >> +
> >> +       debug("%s: %d messages\n", __func__, nmsgs);
> >> +       for (i = 0; i < nmsgs; i++, msg++) {
> >> +               debug("%s: chip=0x%x, len=0x%x\n", __func__, msg->addr,
> >> +                     msg->len);
> >> +
> >> +               if (msg->flags & I2C_M_RD) {
> >> +                       debug("%s: Reading data\n", __func__);
> >> +                       ret = twsi_read_data(twsi->base, msg->addr,
> >> +                                            msg->buf, msg->len);
> >> +               } else {
> >> +                       debug("%s: Writing data\n", __func__);
> >> +                       ret = twsi_write_data(twsi->base, msg->addr,
> >> +                                             msg->buf, msg->len);
> >> +               }
> >> +               if (ret) {
> >> +                       debug("%s: error sending\n", __func__);
> >> +                       return -EREMOTEIO;
> >> +               }
> >> +       }
> >> +
> >> +       return 0;
> >> +}
> >> +
> >> +/**
> >> + * Set I2C bus speed
> >> + *
> >> + * @bus                i2c bus to transfer data over
> >> + * @speed      Speed in Hz to set
> >> + * @return     0 for success, otherwise error
> >> + */
> >> +static int octeon_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
> >> +{
> >> +       struct octeon_twsi *twsi = dev_get_priv(bus);
> >> +       int m_div, n_div;
> >> +       u64 val;
> >> +
> >> +       debug("%s(%p, %u)\n", __func__, bus, speed);
> >> +
> >> +       twsi_calc_div(speed, &m_div, &n_div);
> >> +       if (m_div >= 16)
> >> +               return -1;
> >> +
> >> +       val = (u32)(((m_div & 0xf) << 3) | ((n_div & 0x7) << 0)) |
> >> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CLKCTL) |
> >> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
> >> +               TWSI_SW_V;
> >> +       /* Only init non-slave ports */
> >> +       writeq(val, twsi->base + TWSI_SW_TWSI);
> >> +
> >> +       debug("%s: Wrote 0x%llx to sw_twsi\n", __func__, val);
> >> +       return 0;
> >> +}
> >> +
> >> +/**
> >> + * Driver probe function
> >> + *
> >> + * @dev                I2C device to probe
> >> + * @return     0 for success, otherwise error
> >> + */
> >> +static int octeon_pci_i2c_probe(struct udevice *dev)
> >> +{
> >> +       struct octeon_twsi *twsi = dev_get_priv(dev);
> >> +#if !defined(CONFIG_ARCH_OCTEON)
> >> +       pci_dev_t bdf = dm_pci_get_bdf(dev);
> >> +
> >> +       debug("TWSI PCI device: %x\n", bdf);
> >> +       dev->req_seq = PCI_FUNC(bdf);
> >> +
> >> +       twsi->base = dm_pci_map_bar(dev, PCI_BASE_ADDRESS_0,
> >> +                                   PCI_REGION_MEM);
> >> +#else
> >> +       twsi->base = dev_remap_addr(dev);
> >> +#endif
> >> +       debug("TWSI bus %d at %p\n", dev->seq, twsi->base);
> >> +
> >> +       /* Start with standard speed, real speed set via DT or cmd */
> >> +       return twsi_init(twsi->base, CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR);
> >> +}
> >> +
> >> +static const struct dm_i2c_ops octeon_i2c_ops = {
> >> +       .xfer           = octeon_i2c_xfer,
> >> +       .set_bus_speed  = octeon_i2c_set_bus_speed,
> >> +};
> >> +
> >> +static const struct udevice_id octeon_i2c_ids[] = {
> >> +       { .compatible = "cavium,thunder-8890-twsi" },
> >> +       { .compatible = "cavium,octeon-7890-twsi" },
> >> +       { }
> >> +};
> >> +
> >> +U_BOOT_DRIVER(octeon_pci_twsi) = {
> >> +       .name   = "i2c_octeon",
> >> +       .id     = UCLASS_I2C,
> >> +       .of_match = octeon_i2c_ids,
> >> +       .probe  = octeon_pci_i2c_probe,
> >> +       .priv_auto_alloc_size = sizeof(struct octeon_twsi),
> >> +       .ops    = &octeon_i2c_ops,
> >> +};
> >> +
> >> +#if !defined(CONFIG_ARCH_OCTEON)
> >> +static struct pci_device_id octeon_twsi_supported[] = {
> >> +       { PCI_VDEVICE(CAVIUM, PCI_DEVICE_ID_CAVIUM_TWSI) },
> >> +       { },
> >> +};
> >> +
> >> +U_BOOT_PCI_DEVICE(octeon_pci_twsi, octeon_twsi_supported);
> >> +#endif
> >> --
> >> 2.26.2
> >>
>
>
> Viele Gr??e,
> Stefan
>
> --
> DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> Phone: (+49)-8142-66989-51 Fax: (+49)-8142-66989-80 Email: sr at denx.de

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon
  2020-06-03  5:37     ` Rayagonda Kokatanur
@ 2020-06-03  5:39       ` Stefan Roese
  0 siblings, 0 replies; 9+ messages in thread
From: Stefan Roese @ 2020-06-03  5:39 UTC (permalink / raw)
  To: u-boot

On 03.06.20 07:37, Rayagonda Kokatanur wrote:
> On Wed, Jun 3, 2020 at 10:50 AM Stefan Roese <sr@denx.de> wrote:
>>
>> Hi Rayagonda,
>>
>> v1 is superseeded. Please review the latest version, v2:
>>
>> https://patchwork.ozlabs.org/project/uboot/patch/20200526121307.2735-1-sr at denx.de/
> 
> Thank you, I missed that v2.
> Anyway please ignore my comments, all of them are fixed in v2.

Good. Could you please send a Reviewed-by tag then?

Thanks,
Stefan

> Thanks,
> Rayagonda
>>
>> Thanks,
>> Stefan
>>
>> On 03.06.20 07:15, Rayagonda Kokatanur wrote:
>>> Hi Stefan,
>>>
>>> Few minor comments,
>>>
>>> On Thu, May 14, 2020 at 12:53 PM Stefan Roese <sr@denx.de> wrote:
>>>>
>>>> From: Suneel Garapati <sgarapati@marvell.com>
>>>>
>>>> Add support for I2C controllers found on Octeon II/III and Octeon TX
>>>> TX2 SoC platforms.
>>>>
>>>> Signed-off-by: Aaron Williams <awilliams@marvell.com>
>>>> Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
>>>> Signed-off-by: Stefan Roese <sr@denx.de>
>>>> Cc: Heiko Schocher <hs@denx.de>
>>>> Cc: Simon Glass <sjg@chromium.org>
>>>> Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
>>>> Cc: Aaron Williams <awilliams@marvell.com>
>>>> Cc: Chandrakala Chavva <cchavva@marvell.com>
>>>> ---
>>>> RFC -> v1 (Stefan):
>>>> - Separated this patch from the OcteonTX/TX2 RFC patch series into a
>>>>     single patch. This is useful, as the upcoming MIPS Octeon support will
>>>>     use this I2C driver.
>>>> - Added MIPS Octeon II/III support (big endian). Rename driver and its
>>>>     function names from "octeontx" to "octeon" to better match all Octeon
>>>>     platforms.
>>>> - Moved from union to defines / bitmasks as suggested by Simon. This makes
>>>>     the driver usage on little- and big-endian platforms much easier.
>>>> - Enhanced Kconfig text
>>>> - Removed all clock macros (use values from DT)
>>>> - Removed long driver debug strings. This is only available when a debug
>>>>     version of this driver is built. The user / developer can lookup the
>>>>     descriptive error messages in the driver in this case anyway.
>>>> - Removed static "last_id"
>>>> - Dropped misc blank lines. Misc reformatting.
>>>> - Dropped "!= 0"
>>>> - Added missing function comments
>>>> - Added missing strut comments
>>>> - Changed comment style
>>>> - Renames "result" to "ret"
>>>> - Hex numbers uppercase
>>>> - Minor other changes
>>>> - Reword commit text and subject
>>>>
>>>>    drivers/i2c/Kconfig      |  10 +
>>>>    drivers/i2c/Makefile     |   1 +
>>>>    drivers/i2c/octeon_i2c.c | 803 +++++++++++++++++++++++++++++++++++++++
>>>>    3 files changed, 814 insertions(+)
>>>>    create mode 100644 drivers/i2c/octeon_i2c.c
>>>>
>>>> diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
>>>> index e42b6516bf..1330b36698 100644
>>>> --- a/drivers/i2c/Kconfig
>>>> +++ b/drivers/i2c/Kconfig
>>>> @@ -374,6 +374,16 @@ config SYS_I2C_SANDBOX
>>>>             bus. Devices can be attached to the bus using the device tree
>>>>             which specifies the driver to use.  See sandbox.dts as an example.
>>>>
>>>> +config SYS_I2C_OCTEON
>>>> +       bool "Octeon II/III/TX/TX2 I2C driver"
>>>> +       depends on (ARCH_OCTEON || ARCH_OCTEONTX || ARCH_OCTEONTX2) && DM_I2C
>>>> +       default y
>>>> +       help
>>>> +         Add support for the Marvell Octeon I2C driver. This is used with
>>>> +         various Octeon parts such as Octeon II/III and OcteonTX/TX2. All
>>>> +         chips have several I2C ports and all are provided, controlled by
>>>> +         the device tree.
>>>> +
>>>>    config SYS_I2C_S3C24X0
>>>>           bool "Samsung I2C driver"
>>>>           depends on ARCH_EXYNOS4 && DM_I2C
>>>> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
>>>> index 62935b7ebc..2b58aae892 100644
>>>> --- a/drivers/i2c/Makefile
>>>> +++ b/drivers/i2c/Makefile
>>>> @@ -27,6 +27,7 @@ obj-$(CONFIG_SYS_I2C_LPC32XX) += lpc32xx_i2c.o
>>>>    obj-$(CONFIG_SYS_I2C_MESON) += meson_i2c.o
>>>>    obj-$(CONFIG_SYS_I2C_MVTWSI) += mvtwsi.o
>>>>    obj-$(CONFIG_SYS_I2C_MXC) += mxc_i2c.o
>>>> +obj-$(CONFIG_SYS_I2C_OCTEON) += octeon_i2c.o
>>>>    obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
>>>>    obj-$(CONFIG_SYS_I2C_RCAR_I2C) += rcar_i2c.o
>>>>    obj-$(CONFIG_SYS_I2C_RCAR_IIC) += rcar_iic.o
>>>> diff --git a/drivers/i2c/octeon_i2c.c b/drivers/i2c/octeon_i2c.c
>>>> new file mode 100644
>>>> index 0000000000..210f98655e
>>>> --- /dev/null
>>>> +++ b/drivers/i2c/octeon_i2c.c
>>>> @@ -0,0 +1,803 @@
>>>> +// SPDX-License-Identifier:    GPL-2.0
>>>> +/*
>>>> + * Copyright (C) 2018 Marvell International Ltd.
>>>
>>> Should it  be 2020 ?
>>>> + */
>>>> +
>>>> +#include <common.h>
>>>> +#include <i2c.h>
>>>> +#include <dm.h>
>>>> +#include <pci_ids.h>
>>>> +#include <asm/io.h>
>>>> +#include <asm/arch/clock.h>
>>>> +#include <linux/bitfield.h>
>>>> +
>>>> +/*
>>>> + * Octeon II/III (MIPS) have different register offsets than the ARM based
>>>> + * Octeon TX/TX2 SoCs
>>>> + */
>>>> +#if defined(CONFIG_ARCH_OCTEON)
>>>> +#define REG_OFFS               0x0000
>>>> +#else
>>>> +#define REG_OFFS               0x1000
>>>> +#endif
>>>
>>> How about getting this offset from dt ?
>>>> +
>>>> +#define TWSI_SW_TWSI           (REG_OFFS + 0x00)
>>>> +#define TWSI_TWSI_SW           (REG_OFFS + 0x08)
>>>> +#define TWSI_INT               (REG_OFFS + 0x10)
>>>> +#define TWSI_SW_TWSI_EXT       (REG_OFFS + 0x18)
>>>> +
>>>> +#define TWSI_SW_DATA_MASK      GENMASK_ULL(31, 0)
>>>> +#define TWSI_SW_EOP_IA_MASK    GENMASK_ULL(34, 32)
>>>> +#define TWSI_SW_IA_MASK                GENMASK_ULL(39, 35)
>>>> +#define TWSI_SW_ADDR_MASK      GENMASK_ULL(49, 40)
>>>> +#define TWSI_SW_SCR_MASK       GENMASK_ULL(51, 50)
>>>> +#define TWSI_SW_SIZE_MASK      GENMASK_ULL(54, 52)
>>>> +#define TWSI_SW_SOVR           BIT_ULL(55)
>>>> +#define TWSI_SW_R              BIT_ULL(56)
>>>> +#define TWSI_SW_OP_MASK                GENMASK_ULL(60, 57)
>>>> +#define TWSI_SW_EIA            GENMASK_ULL(61)
>>>> +#define TWSI_SW_SLONLY         BIT_ULL(62)
>>>> +#define TWSI_SW_V              BIT_ULL(63)
>>>> +
>>>> +#define TWSI_INT_SDA_OVR       BIT_ULL(8)
>>>> +#define TWSI_INT_SCL_OVR       BIT_ULL(9)
>>>> +#define TWSI_INT_SDA           BIT_ULL(10)
>>>> +#define TWSI_INT_SCL           BIT_ULL(11)
>>>> +
>>>> +enum {
>>>> +       TWSI_OP_WRITE   = 0,
>>>> +       TWSI_OP_READ    = 1,
>>>> +};
>>>> +
>>>> +enum {
>>>> +       TWSI_EOP_SLAVE_ADDR = 0,
>>>> +       TWSI_EOP_CLK_CTL = 3,
>>>> +       TWSI_SW_EOP_IA   = 6,
>>>> +};
>>>> +
>>>> +enum {
>>>> +       TWSI_SLAVEADD     = 0,
>>>> +       TWSI_DATA         = 1,
>>>> +       TWSI_CTL          = 2,
>>>> +       TWSI_CLKCTL       = 3,
>>>> +       TWSI_STAT         = 3,
>>>> +       TWSI_SLAVEADD_EXT = 4,
>>>> +       TWSI_RST          = 7,
>>>> +};
>>>> +
>>>> +enum {
>>>> +       TWSI_CTL_AAK    = BIT(2),
>>>> +       TWSI_CTL_IFLG   = BIT(3),
>>>> +       TWSI_CTL_STP    = BIT(4),
>>>> +       TWSI_CTL_STA    = BIT(5),
>>>> +       TWSI_CTL_ENAB   = BIT(6),
>>>> +       TWSI_CTL_CE     = BIT(7),
>>>> +};
>>>> +
>>>> +/*
>>>> + * Internal errors. When debugging is enabled, the driver will report the
>>>> + * error number and the user / developer can check the table below for the
>>>> + * detailed error description.
>>>> + */
>>>> +enum {
>>>> +       /** Bus error */
>>>> +       TWSI_STAT_BUS_ERROR             = 0x00,
>>>> +       /** Start condition transmitted */
>>>> +       TWSI_STAT_START                 = 0x08,
>>>> +       /** Repeat start condition transmitted */
>>>> +       TWSI_STAT_RSTART                = 0x10,
>>>> +       /** Address + write bit transmitted, ACK received */
>>>> +       TWSI_STAT_TXADDR_ACK            = 0x18,
>>>> +       /** Address + write bit transmitted, /ACK received */
>>>> +       TWSI_STAT_TXADDR_NAK            = 0x20,
>>>> +       /** Data byte transmitted in master mode, ACK received */
>>>> +       TWSI_STAT_TXDATA_ACK            = 0x28,
>>>> +       /** Data byte transmitted in master mode, ACK received */
>>>> +       TWSI_STAT_TXDATA_NAK            = 0x30,
>>>> +       /** Arbitration lost in address or data byte */
>>>> +       TWSI_STAT_TX_ARB_LOST           = 0x38,
>>>> +       /** Address + read bit transmitted, ACK received */
>>>> +       TWSI_STAT_RXADDR_ACK            = 0x40,
>>>> +       /** Address + read bit transmitted, /ACK received */
>>>> +       TWSI_STAT_RXADDR_NAK            = 0x48,
>>>> +       /** Data byte received in master mode, ACK transmitted */
>>>> +       TWSI_STAT_RXDATA_ACK_SENT       = 0x50,
>>>> +       /** Data byte received, NACK transmitted */
>>>> +       TWSI_STAT_RXDATA_NAK_SENT       = 0x58,
>>>> +       /** Slave address received, sent ACK */
>>>> +       TWSI_STAT_SLAVE_RXADDR_ACK      = 0x60,
>>>> +       /**
>>>> +        * Arbitration lost in address as master, slave address + write bit
>>>> +        * received, ACK transmitted
>>>> +        */
>>>> +       TWSI_STAT_TX_ACK_ARB_LOST       = 0x68,
>>>> +       /** General call address received, ACK transmitted */
>>>> +       TWSI_STAT_RX_GEN_ADDR_ACK       = 0x70,
>>>> +       /**
>>>> +        * Arbitration lost in address as master, general call address
>>>> +        * received, ACK transmitted
>>>> +        */
>>>> +       TWSI_STAT_RX_GEN_ADDR_ARB_LOST  = 0x78,
>>>> +       /** Data byte received after slave address received, ACK transmitted */
>>>> +       TWSI_STAT_SLAVE_RXDATA_ACK      = 0x80,
>>>> +       /** Data byte received after slave address received, /ACK transmitted */
>>>> +       TWSI_STAT_SLAVE_RXDATA_NAK      = 0x88,
>>>> +       /**
>>>> +        * Data byte received after general call address received, ACK
>>>> +        * transmitted
>>>> +        */
>>>> +       TWSI_STAT_GEN_RXADDR_ACK        = 0x90,
>>>> +       /**
>>>> +        * Data byte received after general call address received, /ACK
>>>> +        * transmitted
>>>> +        */
>>>> +       TWSI_STAT_GEN_RXADDR_NAK        = 0x98,
>>>> +       /** STOP or repeated START condition received in slave mode */
>>>> +       TWSI_STAT_STOP_MULTI_START      = 0xa0,
>>>> +       /** Slave address + read bit received, ACK transmitted */
>>>> +       TWSI_STAT_SLAVE_RXADDR2_ACK     = 0xa8,
>>>> +       /**
>>>> +        * Arbitration lost in address as master, slave address + read bit
>>>> +        * received, ACK transmitted
>>>> +        */
>>>> +       TWSI_STAT_RXDATA_ACK_ARB_LOST   = 0xb0,
>>>> +       /** Data byte transmitted in slave mode, ACK received */
>>>> +       TWSI_STAT_SLAVE_TXDATA_ACK      = 0xb8,
>>>> +       /** Data byte transmitted in slave mode, /ACK received */
>>>> +       TWSI_STAT_SLAVE_TXDATA_NAK      = 0xc0,
>>>> +       /** Last byte transmitted in slave mode, ACK received */
>>>> +       TWSI_STAT_SLAVE_TXDATA_END_ACK  = 0xc8,
>>>> +       /** Second address byte + write bit transmitted, ACK received */
>>>> +       TWSI_STAT_TXADDR2DATA_ACK       = 0xd0,
>>>> +       /** Second address byte + write bit transmitted, /ACK received */
>>>> +       TWSI_STAT_TXADDR2DATA_NAK       = 0xd8,
>>>> +       /** No relevant status information */
>>>> +       TWSI_STAT_IDLE                  = 0xf8
>>>> +};
>>>> +
>>>> +#ifndef CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR
>>>> +# define CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR      0x77
>>>> +#endif
>>>> +
>>>> +/**
>>>> + * struct octeon_twsi - Private data of this driver
>>>> + *
>>>> + * @base:      Base address of i2c registers
>>>> + */
>>>> +struct octeon_twsi {
>>>> +       void __iomem *base;
>>>> +};
>>>> +
>>>> +static void twsi_unblock(void *base);
>>>> +static int twsi_stop(void *base);
>>>> +
>>>> +#if defined(CONFIG_ARCH_OCTEON)
>>>> +static int get_io_clock(void)
>>>> +{
>>>> +       return octeon_get_io_clock();
>>>> +}
>>>> +#else
>>>> +static int get_io_clock(void)
>>>> +{
>>>> +       return octeontx_get_io_clock();
>>>> +}
>>>> +#endif
>>>> +
>>>> +static int twsi_thp(void)
>>>> +{
>>>> +       if (IS_ENABLED(CONFIG_ARCH_OCTEON) || IS_ENABLED(CONFIG_ARCH_OCTEONTX))
>>>> +               return 24;
>>>> +       else
>>>> +               return 3;
>>>> +}
>>>> +
>>>> +/**
>>>> + * Returns true if we lost arbitration
>>>> + *
>>>> + * @code       status code
>>>> + * @final_read true if this is the final read operation
>>>> + * @return     true if arbitration has been lost, false if it hasn't been lost.
>>>
>>> Instead of true/false, better to mention 0 on success and -ve on failure.
>>>> + */
>>>> +static int twsi_i2c_lost_arb(u8 code, int final_read)
>>>> +{
>>>> +       switch (code) {
>>>> +       case TWSI_STAT_TX_ARB_LOST:
>>>> +       case TWSI_STAT_TX_ACK_ARB_LOST:
>>>> +       case TWSI_STAT_RX_GEN_ADDR_ARB_LOST:
>>>> +       case TWSI_STAT_RXDATA_ACK_ARB_LOST:
>>>> +               /* Arbitration lost */
>>>> +               return -EAGAIN;
>>>> +
>>>> +       case TWSI_STAT_SLAVE_RXADDR_ACK:
>>>> +       case TWSI_STAT_RX_GEN_ADDR_ACK:
>>>> +       case TWSI_STAT_GEN_RXADDR_ACK:
>>>> +       case TWSI_STAT_GEN_RXADDR_NAK:
>>>> +               /* Being addressed as slave, should back off and listen */
>>>> +               return -EIO;
>>>> +
>>>> +       case TWSI_STAT_SLAVE_RXDATA_ACK:
>>>> +       case TWSI_STAT_SLAVE_RXDATA_NAK:
>>>> +       case TWSI_STAT_STOP_MULTI_START:
>>>> +       case TWSI_STAT_SLAVE_RXADDR2_ACK:
>>>> +       case TWSI_STAT_SLAVE_TXDATA_ACK:
>>>> +       case TWSI_STAT_SLAVE_TXDATA_NAK:
>>>> +       case TWSI_STAT_SLAVE_TXDATA_END_ACK:
>>>> +               /* Core busy as slave */
>>>> +               return  -EIO;
>>>> +
>>>> +       case TWSI_STAT_RXDATA_ACK_SENT:
>>>> +               /* Ack allowed on pre-terminal bytes only */
>>>> +               if (!final_read)
>>>> +                       return 0;
>>>> +               return -EAGAIN;
>>>> +
>>>> +       case TWSI_STAT_RXDATA_NAK_SENT:
>>>> +               /* NAK allowed on terminal byte only */
>>>> +               if (!final_read)
>>>> +                       return 0;
>>>> +               return -EAGAIN;
>>>> +
>>>> +       case TWSI_STAT_TXDATA_NAK:
>>>> +       case TWSI_STAT_TXADDR_NAK:
>>>> +       case TWSI_STAT_RXADDR_NAK:
>>>> +       case TWSI_STAT_TXADDR2DATA_NAK:
>>>> +               return -EAGAIN;
>>>> +       }
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +#define RST_BOOT_PNR_MUL(val)  (((val) >> 33) & 0x1F)
>>>
>>> Better to move this up where all macros are defined.
>>>
>>>> +
>>>> +/**
>>>> + * Writes to the MIO_TWS(0..5)_SW_TWSI register
>>>> + *
>>>> + * @base       Base address of i2c registers
>>>> + * @val                value to write
>>>> + * @return     0 for success, otherwise error
>>>> + */
>>>> +static u64 twsi_write_sw(void __iomem *base, u64 val)
>>>> +{
>>>> +       unsigned long start = get_timer(0);
>>>> +
>>>> +       val &= ~TWSI_SW_R;
>>>> +       val |= TWSI_SW_V;
>>>> +
>>>> +       debug("%s(%p, 0x%llx)\n", __func__, base, val);
>>>> +       writeq(val, base + TWSI_SW_TWSI);
>>>> +       do {
>>>> +               val = readq(base + TWSI_SW_TWSI);
>>>> +       } while ((val & TWSI_SW_V) && (get_timer(start) < 50));
>>>> +
>>>> +       if (val & TWSI_SW_V)
>>>> +               debug("%s: timed out\n", __func__);
>>>> +       return val;
>>>
>>> newline before return, please fix globally.
>>>> +}
>>>> +
>>>> +/**
>>>> + * Reads the MIO_TWS(0..5)_SW_TWSI register
>>>> + *
>>>> + * @base       Base address of i2c registers
>>>> + * @val                value for eia and op, etc. to read
>>>> + * @return     value of the register
>>>> + */
>>>> +static u64 twsi_read_sw(void __iomem *base, u64 val)
>>>> +{
>>>> +       unsigned long start = get_timer(0);
>>>> +
>>>> +       val |= TWSI_SW_R | TWSI_SW_V;
>>>> +
>>>> +       debug("%s(%p, 0x%llx)\n", __func__, base, val);
>>>> +       writeq(val, base + TWSI_SW_TWSI);
>>>> +
>>>> +       do {
>>>> +               val = readq(base + TWSI_SW_TWSI);
>>>> +       } while ((val & TWSI_SW_V) && (get_timer(start) < 50));
>>>> +
>>>> +       if (val & TWSI_SW_V)
>>>> +               debug("%s: Error writing 0x%llx\n", __func__, val);
>>>> +
>>>> +       debug("%s: Returning 0x%llx\n", __func__, val);
>>>> +       return val;
>>>> +}
>>>> +
>>>> +/**
>>>> + * Write control register
>>>> + *
>>>> + * @base       Base address for i2c registers
>>>> + * @data       data to write
>>>> + */
>>>> +static void twsi_write_ctl(void __iomem *base, u8 data)
>>>> +{
>>>> +       u64 val;
>>>> +
>>>> +       debug("%s(%p, 0x%x)\n", __func__, base, data);
>>>> +       val = data | FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CTL) |
>>>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
>>>> +       twsi_write_sw(base, val);
>>>> +}
>>>> +
>>>> +/**
>>>> + * Reads the TWSI Control Register
>>>> + *
>>>> + * @base       Base address for i2c
>>>> + * @return     8-bit TWSI control register
>>>> + */
>>>> +static u8 twsi_read_ctl(void __iomem *base)
>>>> +{
>>>> +       u64 val;
>>>> +
>>>> +       val = FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CTL) |
>>>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
>>>> +       val = twsi_read_sw(base, val);
>>>> +
>>>> +       debug("%s(%p): 0x%x\n", __func__, base, (u8)val);
>>>> +       return (u8)val;
>>>> +}
>>>> +
>>>> +/**
>>>> + * Read i2c status register
>>>> + *
>>>> + * @base       Base address of i2c registers
>>>> + * @return     value of status register
>>>> + */
>>>> +static u8 twsi_read_status(void __iomem *base)
>>>> +{
>>>> +       u64 val;
>>>> +
>>>> +       val = FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_STAT) |
>>>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
>>>> +
>>>> +       return twsi_read_sw(base, val);
>>>> +}
>>>> +
>>>> +/**
>>>> + * Waits for an i2c operation to complete
>>>> + *
>>>> + * @param      base    Base address of registers
>>>> + * @return     0 for success, 1 if timeout
>>>> + */
>>>> +static int twsi_wait(void __iomem *base)
>>>> +{
>>>> +       unsigned long start = get_timer(0);
>>>> +       u8 twsi_ctl;
>>>> +
>>>> +       debug("%s(%p)\n", __func__, base);
>>>> +       do {
>>>> +               twsi_ctl = twsi_read_ctl(base);
>>>> +               twsi_ctl &= TWSI_CTL_IFLG;
>>>> +       } while (!twsi_ctl && get_timer(start) < 50);
>>>> +
>>>> +       debug("  return: %u\n", !twsi_ctl);
>>>> +       return !twsi_ctl;
>>>> +}
>>>> +
>>>> +/**
>>>> + * Unsticks the i2c bus
>>>> + *
>>>> + * @base       base address of registers
>>>> + */
>>>> +static int twsi_start_unstick(void __iomem *base)
>>>> +{
>>>> +       twsi_stop(base);
>>>> +       twsi_unblock(base);
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +/**
>>>> + * Sends an i2c start condition
>>>> + *
>>>> + * @base       base address of registers
>>>> + * @return     0 for success, otherwise error
>>>> + */
>>>> +static int twsi_start(void __iomem *base)
>>>> +{
>>>> +       int ret;
>>>> +       u8 stat;
>>>> +
>>>> +       debug("%s(%p)\n", __func__, base);
>>>> +       twsi_write_ctl(base, TWSI_CTL_STA | TWSI_CTL_ENAB);
>>>> +       ret = twsi_wait(base);
>>>> +       if (ret) {
>>>> +               stat = twsi_read_status(base);
>>>> +               debug("%s: ret: 0x%x, status: 0x%x\n", __func__, ret, stat);
>>>> +               switch (stat) {
>>>> +               case TWSI_STAT_START:
>>>> +               case TWSI_STAT_RSTART:
>>>> +                       return 0;
>>>> +               case TWSI_STAT_RXADDR_ACK:
>>>> +               default:
>>>> +                       return twsi_start_unstick(base);
>>>> +               }
>>>> +       }
>>>> +
>>>> +       debug("%s: success\n", __func__);
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +/**
>>>> + * Sends an i2c stop condition
>>>> + *
>>>> + * @base       register base address
>>>> + * @return     0 for success, -1 if error
>>>> + */
>>>> +static int twsi_stop(void __iomem *base)
>>>> +{
>>>> +       u8 stat;
>>>> +
>>>> +       twsi_write_ctl(base, TWSI_CTL_STP | TWSI_CTL_ENAB);
>>>> +
>>>> +       stat = twsi_read_status(base);
>>>> +       if (stat != TWSI_STAT_IDLE) {
>>>> +               debug("%s: Bad status on bus@%p\n", __func__, base);
>>>> +               return -1;
>>>> +       }
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +/**
>>>> + * Writes data to the i2c bus
>>>> + *
>>>> + * @base       register base address
>>>> + * @slave_addr address of slave to write to
>>>> + * @buffer     Pointer to buffer to write
>>>> + * @length     Number of bytes in buffer to write
>>>> + * @return     0 for success, otherwise error
>>>> + */
>>>> +static int twsi_write_data(void __iomem *base, u8  slave_addr,
>>>> +                          u8 *buffer, unsigned int length)
>>>
>>> This should be properly aligned.
>>>
>>>> +{
>>>> +       unsigned int curr = 0;
>>>> +       u64 val;
>>>> +       int ret;
>>>> +
>>>> +       debug("%s(%p, 0x%x, %p, 0x%x)\n", __func__, base, slave_addr,
>>>> +             buffer, length);
>>>
>>> same alignment.
>>>
>>>> +       ret = twsi_start(base);
>>>> +       if (ret) {
>>>> +               debug("%s: Could not start BUS transaction\n", __func__);
>>>> +               return -1;
>>>> +       }
>>>> +
>>>> +       ret = twsi_wait(base);
>>>> +       if (ret) {
>>>> +               debug("%s: wait failed\n", __func__);
>>>> +               return ret;
>>>> +       }
>>>> +
>>>> +       val = (u32)(slave_addr << 1) | TWSI_OP_WRITE |
>>>> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
>>>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
>>>> +       twsi_write_sw(base, val);
>>>> +       twsi_write_ctl(base, TWSI_CTL_ENAB);
>>>> +
>>>> +       debug("%s: Waiting\n", __func__);
>>>> +       ret = twsi_wait(base);
>>>> +       if (ret) {
>>>> +               debug("%s: Timed out writing slave address 0x%x to target\n",
>>>> +                     __func__, slave_addr);
>>>> +               return ret;
>>>> +       }
>>>> +
>>>> +       ret = twsi_read_status(base);
>>>> +       debug("%s: status: 0x%x\n", __func__, ret);
>>>> +       if (ret != TWSI_STAT_TXADDR_ACK) {
>>>> +               debug("%s: status: 0x%x\n", __func__, ret);
>>>> +               twsi_stop(base);
>>>> +               return twsi_i2c_lost_arb(ret, 0);
>>>> +       }
>>>> +
>>>> +       while (curr < length) {
>>>> +               val = buffer[curr++] |
>>>> +                       FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
>>>> +                       FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
>>>> +               twsi_write_sw(base, val);
>>>> +               twsi_write_ctl(base, TWSI_CTL_ENAB);
>>>> +
>>>> +               debug("%s: Writing 0x%llx\n", __func__, val);
>>>> +
>>>> +               ret = twsi_wait(base);
>>>> +               if (ret) {
>>>> +                       debug("%s: Timed out writing data to 0x%x\n",
>>>> +                             __func__, slave_addr);
>>>> +                       return ret;
>>>> +               }
>>>> +               ret = twsi_read_status(base);
>>>> +               debug("%s: status: 0x%x\n", __func__, ret);
>>>> +       }
>>>> +
>>>> +       debug("%s: Stopping\n", __func__);
>>>> +       return twsi_stop(base);
>>>> +}
>>>> +
>>>> +/**
>>>> + * Manually clear the I2C bus and send a stop
>>>> + *
>>>> + * @base       register base address
>>>> + */
>>>> +static void twsi_unblock(void __iomem *base)
>>>> +{
>>>> +       int i;
>>>> +
>>>> +       for (i = 0; i < 9; i++) {
>>>> +               writeq(0, base + TWSI_INT);
>>>> +               udelay(5);
>>>> +               writeq(TWSI_INT_SCL_OVR, base + TWSI_INT);
>>>> +               udelay(5);
>>>> +       }
>>>> +       writeq(TWSI_INT_SCL_OVR | TWSI_INT_SDA_OVR, base + TWSI_INT);
>>>> +       udelay(5);
>>>> +       writeq(TWSI_INT_SDA_OVR, base + TWSI_INT);
>>>> +       udelay(5);
>>>> +       writeq(0, base + TWSI_INT);
>>>> +       udelay(5);
>>>> +}
>>>> +
>>>> +/**
>>>> + * Performs a read transaction on the i2c bus
>>>> + *
>>>> + * @base       Base address of twsi registers
>>>> + * @slave_addr i2c bus address to read from
>>>> + * @buffer     buffer to read into
>>>> + * @length     number of bytes to read
>>>> + * @return     0 for success, otherwise error
>>>> + */
>>>> +static int twsi_read_data(void __iomem *base, u8 slave_addr,
>>>> +                         u8 *buffer, unsigned int length)
>>>> +{
>>>> +       unsigned int curr = 0;
>>>> +       u64 val;
>>>> +       int ret;
>>>> +
>>>> +       debug("%s(%p, 0x%x, %p, %u)\n", __func__, base, slave_addr,
>>>> +             buffer, length);
>>>> +       ret = twsi_start(base);
>>>> +       if (ret) {
>>>> +               debug("%s: start failed\n", __func__);
>>>> +               return ret;
>>>> +       }
>>>> +
>>>> +       ret = twsi_wait(base);
>>>> +       if (ret) {
>>>> +               debug("%s: wait failed\n", __func__);
>>>> +               return ret;
>>>> +       }
>>>> +
>>>> +       val = (u32)(slave_addr << 1) | TWSI_OP_READ |
>>>> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_DATA) |
>>>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA);
>>>> +       twsi_write_sw(base, val);
>>>> +       twsi_write_ctl(base, TWSI_CTL_ENAB);
>>>> +
>>>> +       ret = twsi_wait(base);
>>>> +       if (ret) {
>>>> +               debug("%s: waiting for sending addr failed\n", __func__);
>>>> +               return ret;
>>>> +       }
>>>> +
>>>> +       ret = twsi_read_status(base);
>>>> +       debug("%s: status: 0x%x\n", __func__, ret);
>>>> +       if (ret != TWSI_STAT_RXADDR_ACK) {
>>>> +               debug("%s: status: 0x%x\n", __func__, ret);
>>>> +               twsi_stop(base);
>>>> +               return twsi_i2c_lost_arb(ret, 0);
>>>> +       }
>>>> +
>>>> +       while (curr < length) {
>>>> +               twsi_write_ctl(base, TWSI_CTL_ENAB |
>>>> +                              ((curr < length - 1) ? TWSI_CTL_AAK : 0));
>>>> +
>>>> +               ret = twsi_wait(base);
>>>> +               if (ret) {
>>>> +                       debug("%s: waiting for data failed\n", __func__);
>>>> +                       return ret;
>>>> +               }
>>>> +
>>>> +               val = twsi_read_sw(base, val);
>>>> +               buffer[curr++] = (u8)val;
>>>> +       }
>>>> +
>>>> +       twsi_stop(base);
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +/**
>>>> + * Calculate the divisor values
>>>> + *
>>>> + * @speed      Speed to set
>>>> + * @m_div      Pointer to M divisor
>>>> + * @n_div      Pointer to N divisor
>>>> + * @return     0 for success, otherwise error
>>>> + */
>>>> +static void twsi_calc_div(unsigned int speed, int *m_div, int *n_div)
>>>> +{
>>>> +       int io_clock_hz;
>>>> +       int tclk, fsamp;
>>>> +       int ndiv, mdiv;
>>>> +
>>>> +#if defined(CONFIG_ARCH_OCTEON) || defined(CONFIG_ARCH_OCTEONTX)
>>>> +       io_clock_hz = get_io_clock();
>>>> +       tclk = io_clock_hz / (2 * (twsi_thp() + 1));
>>>> +#elif defined(CONFIG_ARCH_OCTEONTX2)
>>>> +       /* Refclk src in mode register defaults to 100MHz clock */
>>>> +       io_clock_hz = 100000000; /* 100 Mhz */
>>>> +       tclk = io_clock_hz / (twsi_thp() + 2);
>>>> +#endif
>>>> +       debug("%s( io_clock %u tclk %u)\n", __func__, io_clock_hz, tclk);
>>>> +
>>>> +       /*
>>>> +        * Compute the clocks M divider:
>>>> +        *
>>>> +        * TWSI freq = (core freq) / (10 x (M+1) x 2 * (thp+1) x 2^N)
>>>> +        * M = ((core freq) / (10 x (TWSI freq) x 2 * (thp+1) x 2^N)) - 1
>>>> +        *
>>>> +        * For OcteonTX2 -
>>>> +        * TWSI freq = (core freq) / (10 x (M+1) x (thp+2) x 2^N)
>>>> +        * M = ((core freq) / (10 x (TWSI freq) x (thp+2) x 2^N)) - 1
>>>> +        */
>>>> +       for (ndiv = 0; ndiv < 8; ndiv++) {
>>>> +               fsamp = tclk / (1 << ndiv);
>>>> +               mdiv = fsamp / speed / 10;
>>>> +               mdiv -= 1;
>>>> +               if (mdiv < 16)
>>>> +                       break;
>>>> +       }
>>>> +
>>>> +       *m_div = mdiv;
>>>> +       *n_div = ndiv;
>>>> +}
>>>> +
>>>> +/**
>>>> + * Init I2C controller
>>>> + *
>>>> + * @base       Base address of twsi registers
>>>> + * @slave_addr I2C slave address to configure this controller to
>>>> + * @return     0 for success, otherwise error
>>>> + */
>>>> +static int twsi_init(void __iomem *base, int slaveaddr)
>>>> +{
>>>> +       u64 val;
>>>> +
>>>> +       debug("%s (%p, 0x%x)\n", __func__, base, slaveaddr);
>>>> +
>>>> +       val = slaveaddr << 1 |
>>>> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, 0) |
>>>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
>>>> +               TWSI_SW_V;
>>>> +       twsi_write_sw(base, val);
>>>> +
>>>> +       /* Set slave address */
>>>> +       val = slaveaddr |
>>>> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_EOP_SLAVE_ADDR) |
>>>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
>>>> +               TWSI_SW_V;
>>>> +       twsi_write_sw(base, val);
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +/**
>>>> + * Transfers data over the i2c bus
>>>> + *
>>>> + * @bus                i2c bus to transfer data over
>>>> + * @msg                Array of i2c messages
>>>> + * @nmsgs      Number of messages to send/receive
>>>> + * @return     0 for success, otherwise error
>>>> + */
>>>> +static int octeon_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
>>>> +                          int nmsgs)
>>>> +{
>>>> +       struct octeon_twsi *twsi = dev_get_priv(bus);
>>>> +       int ret;
>>>> +       int i;
>>>> +
>>>> +       debug("%s: %d messages\n", __func__, nmsgs);
>>>> +       for (i = 0; i < nmsgs; i++, msg++) {
>>>> +               debug("%s: chip=0x%x, len=0x%x\n", __func__, msg->addr,
>>>> +                     msg->len);
>>>> +
>>>> +               if (msg->flags & I2C_M_RD) {
>>>> +                       debug("%s: Reading data\n", __func__);
>>>> +                       ret = twsi_read_data(twsi->base, msg->addr,
>>>> +                                            msg->buf, msg->len);
>>>> +               } else {
>>>> +                       debug("%s: Writing data\n", __func__);
>>>> +                       ret = twsi_write_data(twsi->base, msg->addr,
>>>> +                                             msg->buf, msg->len);
>>>> +               }
>>>> +               if (ret) {
>>>> +                       debug("%s: error sending\n", __func__);
>>>> +                       return -EREMOTEIO;
>>>> +               }
>>>> +       }
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +/**
>>>> + * Set I2C bus speed
>>>> + *
>>>> + * @bus                i2c bus to transfer data over
>>>> + * @speed      Speed in Hz to set
>>>> + * @return     0 for success, otherwise error
>>>> + */
>>>> +static int octeon_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
>>>> +{
>>>> +       struct octeon_twsi *twsi = dev_get_priv(bus);
>>>> +       int m_div, n_div;
>>>> +       u64 val;
>>>> +
>>>> +       debug("%s(%p, %u)\n", __func__, bus, speed);
>>>> +
>>>> +       twsi_calc_div(speed, &m_div, &n_div);
>>>> +       if (m_div >= 16)
>>>> +               return -1;
>>>> +
>>>> +       val = (u32)(((m_div & 0xf) << 3) | ((n_div & 0x7) << 0)) |
>>>> +               FIELD_PREP(TWSI_SW_EOP_IA_MASK, TWSI_CLKCTL) |
>>>> +               FIELD_PREP(TWSI_SW_OP_MASK, TWSI_SW_EOP_IA) |
>>>> +               TWSI_SW_V;
>>>> +       /* Only init non-slave ports */
>>>> +       writeq(val, twsi->base + TWSI_SW_TWSI);
>>>> +
>>>> +       debug("%s: Wrote 0x%llx to sw_twsi\n", __func__, val);
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +/**
>>>> + * Driver probe function
>>>> + *
>>>> + * @dev                I2C device to probe
>>>> + * @return     0 for success, otherwise error
>>>> + */
>>>> +static int octeon_pci_i2c_probe(struct udevice *dev)
>>>> +{
>>>> +       struct octeon_twsi *twsi = dev_get_priv(dev);
>>>> +#if !defined(CONFIG_ARCH_OCTEON)
>>>> +       pci_dev_t bdf = dm_pci_get_bdf(dev);
>>>> +
>>>> +       debug("TWSI PCI device: %x\n", bdf);
>>>> +       dev->req_seq = PCI_FUNC(bdf);
>>>> +
>>>> +       twsi->base = dm_pci_map_bar(dev, PCI_BASE_ADDRESS_0,
>>>> +                                   PCI_REGION_MEM);
>>>> +#else
>>>> +       twsi->base = dev_remap_addr(dev);
>>>> +#endif
>>>> +       debug("TWSI bus %d at %p\n", dev->seq, twsi->base);
>>>> +
>>>> +       /* Start with standard speed, real speed set via DT or cmd */
>>>> +       return twsi_init(twsi->base, CONFIG_SYS_I2C_OCTEON_SLAVE_ADDR);
>>>> +}
>>>> +
>>>> +static const struct dm_i2c_ops octeon_i2c_ops = {
>>>> +       .xfer           = octeon_i2c_xfer,
>>>> +       .set_bus_speed  = octeon_i2c_set_bus_speed,
>>>> +};
>>>> +
>>>> +static const struct udevice_id octeon_i2c_ids[] = {
>>>> +       { .compatible = "cavium,thunder-8890-twsi" },
>>>> +       { .compatible = "cavium,octeon-7890-twsi" },
>>>> +       { }
>>>> +};
>>>> +
>>>> +U_BOOT_DRIVER(octeon_pci_twsi) = {
>>>> +       .name   = "i2c_octeon",
>>>> +       .id     = UCLASS_I2C,
>>>> +       .of_match = octeon_i2c_ids,
>>>> +       .probe  = octeon_pci_i2c_probe,
>>>> +       .priv_auto_alloc_size = sizeof(struct octeon_twsi),
>>>> +       .ops    = &octeon_i2c_ops,
>>>> +};
>>>> +
>>>> +#if !defined(CONFIG_ARCH_OCTEON)
>>>> +static struct pci_device_id octeon_twsi_supported[] = {
>>>> +       { PCI_VDEVICE(CAVIUM, PCI_DEVICE_ID_CAVIUM_TWSI) },
>>>> +       { },
>>>> +};
>>>> +
>>>> +U_BOOT_PCI_DEVICE(octeon_pci_twsi, octeon_twsi_supported);
>>>> +#endif
>>>> --
>>>> 2.26.2
>>>>
>>
>>
>> Viele Gr??e,
>> Stefan
>>
>> --
>> DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
>> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
>> Phone: (+49)-8142-66989-51 Fax: (+49)-8142-66989-80 Email: sr at denx.de


Viele Gr??e,
Stefan

-- 
DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-51 Fax: (+49)-8142-66989-80 Email: sr at denx.de

^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2020-06-03  5:39 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-05-14  7:23 [PATCH v1] i2c: octeon_i2c: Add I2C controller driver for Octeon Stefan Roese
2020-05-19  6:07 ` Heiko Schocher
2020-05-26  6:49   ` Stefan Roese
2020-05-19 12:32 ` Simon Glass
2020-05-26 10:55   ` Stefan Roese
2020-06-03  5:15 ` Rayagonda Kokatanur
2020-06-03  5:20   ` Stefan Roese
2020-06-03  5:37     ` Rayagonda Kokatanur
2020-06-03  5:39       ` Stefan Roese

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