Subject: [PATCH 1/6 v2] serial: qcom: add support for GENI serial driver

Subject: [PATCH 1/6 v2] serial: qcom: add support for GENI serial driver

[Дмитрий Санковский]

From b2516d965ee933bdb10fc158e36dedcf65bd7ce9 Mon Sep 17 00:00:00 2001
From: Dzmitry Sankouski <dsankouski@gmail.com>
Date: Fri, 27 Aug 2021 17:47:22 +0300
Subject: [PATCH 1/6 v2] serial: qcom: add support for GENI serial driver

Generic Interface (GENI) Serial Engine (SE) based uart
can be found on newer qualcomm SOCs, starting from SDM845.
Tested on Samsung SM-G9600(starqltechn)
by chain-loading u-boot with stock bootloader.

Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com>
Cc: Ramon Fried <rfried.dev@gmail.com>
---
Changes for v2:
- change functions return type to void, where possible
- remove '.' from summary line

 MAINTAINERS                                   |   1 +
 .../serial/msm-geni-serial.txt                |   6 +
 drivers/serial/Kconfig                        |  17 +
 drivers/serial/Makefile                       |   1 +
 drivers/serial/serial_msm_geni.c              | 579 ++++++++++++++++++
 5 files changed, 604 insertions(+)
 create mode 100644 doc/device-tree-bindings/serial/msm-geni-serial.txt
 create mode 100644 drivers/serial/serial_msm_geni.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 776ff703b9..52ddc99cda 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -390,6 +390,7 @@ F: drivers/gpio/msm_gpio.c
 F: drivers/mmc/msm_sdhci.c
 F: drivers/phy/msm8916-usbh-phy.c
 F: drivers/serial/serial_msm.c
+F: drivers/serial/serial_msm_geni.c
 F: drivers/smem/msm_smem.c
 F: drivers/usb/host/ehci-msm.c

diff --git a/doc/device-tree-bindings/serial/msm-geni-serial.txt
b/doc/device-tree-bindings/serial/msm-geni-serial.txt
new file mode 100644
index 0000000000..9eadc2561b
--- /dev/null
+++ b/doc/device-tree-bindings/serial/msm-geni-serial.txt
@@ -0,0 +1,6 @@
+Qualcomm GENI UART
+
+Required properties:
+- compatible: must be "qcom,msm-geni-uart"
+- reg: start address and size of the registers
+- clock: interface clock (must accept baudrate as a frequency)
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 93348c0929..b420a5720d 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -278,6 +278,14 @@ config DEBUG_UART_S5P
   will need to provide parameters to make this work. The driver will
   be available until the real driver-model serial is running.

+config DEBUG_UART_MSM_GENI
+ bool "Qualcomm snapdragon"
+ depends on ARCH_SNAPDRAGON
+ help
+  Select this to enable a debug UART using the serial_msm driver. You
+  will need to provide parameters to make this work. The driver will
+  be available until the real driver-model serial is running.
+
 config DEBUG_UART_MESON
  bool "Amlogic Meson"
  depends on MESON_SERIAL
@@ -783,6 +791,15 @@ config MSM_SERIAL
   for example APQ8016 and MSM8916.
   Single baudrate is supported in current implementation (115200).

+config MSM_GENI_SERIAL
+ bool "Qualcomm on-chip GENI UART"
+ help
+  Support UART based on Generic Interface (GENI) Serial Engine (SE), used
on Qualcomm Snapdragon SoCs.
+  Should support all qualcomm SOCs with Qualcomm Universal Peripheral
(QUP) Wrapper cores,
+  i.e. newer ones, starting from SDM845.
+  Driver works in FIFO mode.
+  Multiple baudrates supported.
+
 config OCTEON_SERIAL_BOOTCMD
  bool "MIPS Octeon PCI remote bootcmd input"
  depends on ARCH_OCTEON
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index 3cbea8156f..d44caf4ea2 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_PIC32_SERIAL) += serial_pic32.o
 obj-$(CONFIG_BCM283X_MU_SERIAL) += serial_bcm283x_mu.o
 obj-$(CONFIG_BCM283X_PL011_SERIAL) += serial_bcm283x_pl011.o
 obj-$(CONFIG_MSM_SERIAL) += serial_msm.o
+obj-$(CONFIG_MSM_GENI_SERIAL) += serial_msm_geni.o
 obj-$(CONFIG_MVEBU_A3700_UART) += serial_mvebu_a3700.o
 obj-$(CONFIG_MPC8XX_CONS) += serial_mpc8xx.o
 obj-$(CONFIG_NULLDEV_SERIAL) += serial_nulldev.o
diff --git a/drivers/serial/serial_msm_geni.c
b/drivers/serial/serial_msm_geni.c
new file mode 100644
index 0000000000..833e7df82e
--- /dev/null
+++ b/drivers/serial/serial_msm_geni.c
@@ -0,0 +1,579 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Qualcomm GENI serial engine UART driver
+ *
+ * (C) Copyright 2021 Dzmitry Sankouski <dsankouski@gmail.com>
+ *
+ * Based on Linux driver.
+ */
+
+#include <asm/io.h>
+#include <clk.h>
+#include <common.h>
+#include <dm.h>
+#include <dm/pinctrl.h>
+#include <errno.h>
+#include <linux/compiler.h>
+#include <log.h>
+#include <malloc.h>
+#include <serial.h>
+#include <watchdog.h>
+
+#define UART_OVERSAMPLING (32)
+#define STALE_TIMEOUT (160)
+#define SE_UART_RX_STALE_CNT (0x294)
+#define S_GENI_CMD_ABORT (BIT(1))
+
+#define SE_GENI_S_CMD_CTRL_REG (0x634)
+#define SE_GENI_M_CMD_CTRL_REG (0x604)
+
+/* GENI_M_CMD_CTRL_REG */
+#define M_GENI_CMD_CANCEL BIT(2)
+#define M_GENI_CMD_ABORT BIT(1)
+#define M_GENI_DISABLE BIT(0)
+
+/* GENI_S_CMD0 fields */
+#define S_OPCODE_MSK GENMASK(31, 27)
+#define S_OPCODE_SHFT 27
+#define S_PARAMS_MSK GENMASK(26, 0)
+
+/* GENI_STATUS fields */
+#define M_GENI_CMD_ACTIVE BIT(0)
+#define S_GENI_CMD_ACTIVE BIT(12)
+#define S_CMD_DONE_EN (BIT(0))
+#define M_CMD_DONE_EN (BIT(0))
+
+#define USEC_PER_SEC 1000000L
+
+#define SE_GENI_STATUS 0x40
+#define GENI_SER_M_CLK_CFG (0x48)
+#define GENI_SER_S_CLK_CFG (0x4C)
+#define SE_GENI_M_CMD0 0x600
+#define SE_GENI_M_IRQ_CLEAR 0x618
+#define SE_GENI_S_IRQ_STATUS (0x640)
+#define SE_GENI_S_IRQ_CLEAR (0x648)
+#define SE_GENI_S_IRQ_EN (0x644)
+#define SE_GENI_M_IRQ_EN (0x614)
+#define SE_GENI_TX_FIFOn 0x700
+#define SE_GENI_RX_FIFOn 0x780
+#define SE_GENI_TX_FIFO_STATUS 0x800
+#define SE_GENI_RX_FIFO_STATUS 0x804
+#define SE_GENI_TX_WATERMARK_REG (0x80C)
+#define M_TX_FIFO_WATERMARK_EN (BIT(30))
+#define DEF_TX_WM (2)
+#define SE_UART_TX_TRANS_LEN 0x270
+#define SE_GENI_TX_PACKING_CFG0 0x260
+#define SE_GENI_TX_PACKING_CFG1 0x264
+#define SE_GENI_RX_PACKING_CFG0 0x284
+#define SE_GENI_RX_PACKING_CFG1 0x288
+#define SE_UART_TX_STOP_BIT_LEN 0x26c
+#define SE_UART_TX_WORD_LEN 0x268
+#define SE_UART_RX_WORD_LEN 0x28c
+#define SE_UART_RX_TRANS_CFG 0x280
+#define SE_UART_RX_PARITY_CFG 0x2a8
+#define SE_UART_TX_TRANS_CFG 0x25c
+#define SE_UART_TX_PARITY_CFG 0x2a4
+
+#define GENI_FORCE_DEFAULT_REG (0x20)
+/* GENI_FORCE_DEFAULT_REG fields */
+#define FORCE_DEFAULT (BIT(0))
+
+#define S_CMD_ABORT_EN (BIT(5))
+
+#define SE_GENI_S_CMD0 (0x630)
+#define UART_START_READ (0x1)
+
+/* GENI_M_CMD_CTRL_REG */
+#define M_GENI_CMD_CANCEL BIT(2)
+#define M_GENI_CMD_ABORT BIT(1)
+#define M_GENI_DISABLE BIT(0)
+
+#define M_CMD_ABORT_EN BIT(5)
+
+#define M_CMD_DONE_EN (BIT(0))
+#define M_CMD_DONE_DISABLE_MASK ~M_CMD_DONE_EN
+#define SE_GENI_M_IRQ_STATUS (0x610)
+
+#define M_OPCODE_SHIFT (27)
+#define S_OPCODE_SHIFT (27)
+#define M_TX_FIFO_WATERMARK_EN (BIT(30))
+#define UART_START_TX (0x1)
+#define UART_CTS_MASK BIT(1)
+#define M_SEC_IRQ_EN (BIT(31))
+#define TX_FIFO_WC_MSK (GENMASK(27, 0))
+#define RX_FIFO_WC_MSK (GENMASK(24, 0))
+
+#define S_RX_FIFO_WATERMARK_EN (BIT(26))
+#define S_RX_FIFO_LAST_EN (BIT(27))
+#define M_RX_FIFO_WATERMARK_EN (BIT(26))
+#define M_RX_FIFO_LAST_EN (BIT(27))
+
+/* GENI_SER_M_CLK_CFG/GENI_SER_S_CLK_CFG */
+#define SER_CLK_EN (BIT(0))
+#define CLK_DIV_MSK (GENMASK(15, 4))
+#define CLK_DIV_SHFT (4)
+
+#define SE_HW_PARAM_0 (0xE24)
+/* SE_HW_PARAM_0 fields */
+#define TX_FIFO_WIDTH_MSK (GENMASK(29, 24))
+#define TX_FIFO_WIDTH_SHFT (24)
+#define TX_FIFO_DEPTH_MSK (GENMASK(21, 16))
+#define TX_FIFO_DEPTH_SHFT (16)
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct msm_serial_data {
+ phys_addr_t base;
+ u32 baud;
+};
+
+static int get_clk_cfg(unsigned long clk_freq, unsigned long *ser_clk) {
+ unsigned long root_freq[] = {7372800,  14745600, 19200000, 29491200,
+     32000000, 48000000, 64000000, 80000000,
+     96000000, 100000000};
+ int i;
+ int match = -1;
+
+ for (i = 0; i < ARRAY_SIZE(root_freq); i++) {
+ if (clk_freq > root_freq[i])
+ continue;
+
+ if (!(root_freq[i] % clk_freq)) {
+ match = i;
+ break;
+ }
+ }
+ if (match != -1)
+ *ser_clk = root_freq[match];
+ else
+ pr_err("clk_freq %ld\n", clk_freq);
+ return match;
+}
+
+static int get_clk_div_rate(u32 baud, u64 *desired_clk_rate) {
+ unsigned long ser_clk;
+ int dfs_index;
+ int clk_div = 0;
+
+ *desired_clk_rate = baud * UART_OVERSAMPLING;
+ dfs_index = get_clk_cfg(*desired_clk_rate, &ser_clk);
+ if (dfs_index < 0) {
+ pr_err("%s: Can't find matching DFS entry for baud %d\n",
+       __func__, baud);
+ clk_div = -EINVAL;
+ goto exit_get_clk_div_rate;
+ }
+
+ clk_div = ser_clk / *desired_clk_rate;
+ *desired_clk_rate = ser_clk;
+exit_get_clk_div_rate:
+ return clk_div;
+}
+
+static int geni_serial_set_clock_rate(struct udevice *dev, u64 rate) {
+ struct clk *clk;
+ int ret;
+
+ clk = devm_clk_get(dev, "se-clk");
+ if (!clk)
+ return -EINVAL;
+
+ ret = clk_set_rate(clk, rate);
+ return ret;
+}
+
+/**
+ * geni_se_get_tx_fifo_depth() - Get the TX fifo depth of the serial engine
+ * @base: Pointer to the concerned serial engine.
+ *
+ * This function is used to get the depth i.e. number of elements in the
+ * TX fifo of the serial engine.
+ *
+ * Return: TX fifo depth in units of FIFO words.
+ */
+static inline u32 geni_se_get_tx_fifo_depth(long base) {
+ u32 tx_fifo_depth;
+
+ tx_fifo_depth = ((readl(base + SE_HW_PARAM_0) & TX_FIFO_DEPTH_MSK) >>
+ TX_FIFO_DEPTH_SHFT);
+ return tx_fifo_depth;
+}
+
+/**
+ * geni_se_get_tx_fifo_width() - Get the TX fifo width of the serial engine
+ * @base: Pointer to the concerned serial engine.
+ *
+ * This function is used to get the width i.e. word size per element in the
+ * TX fifo of the serial engine.
+ *
+ * Return: TX fifo width in bits
+ */
+static inline u32 geni_se_get_tx_fifo_width(long base) {
+ u32 tx_fifo_width;
+
+ tx_fifo_width = ((readl(base + SE_HW_PARAM_0) & TX_FIFO_WIDTH_MSK) >>
+ TX_FIFO_WIDTH_SHFT);
+ return tx_fifo_width;
+}
+
+static inline void geni_serial_baud(phys_addr_t base_address, u64 uclk,
+ int baud) {
+ u32 clk_div;
+ u32 s_clk_cfg = 0;
+
+ clk_div = get_clk_div_rate(baud, &uclk);
+
+ s_clk_cfg |= SER_CLK_EN;
+ s_clk_cfg |= (clk_div << CLK_DIV_SHFT);
+
+ writel(s_clk_cfg, base_address + GENI_SER_M_CLK_CFG);
+ writel(s_clk_cfg, base_address + GENI_SER_S_CLK_CFG);
+}
+
+int msm_serial_setbrg(struct udevice *dev, int baud) {
+ struct msm_serial_data *priv = dev_get_priv(dev);
+
+ priv->baud = baud;
+ u32 clk_div;
+ u64 clk_rate;
+
+ clk_div = get_clk_div_rate(baud, &clk_rate);
+ geni_serial_set_clock_rate(dev, clk_rate);
+ geni_serial_baud(priv->base, clk_rate, baud);
+
+ return 0;
+}
+
+static bool qcom_geni_serial_poll_bit(const struct udevice *dev, int
offset,
+      int field, bool set) {
+ u32 reg;
+ struct msm_serial_data *priv = dev_get_priv(dev);
+ unsigned int baud;
+ unsigned int tx_fifo_depth;
+ unsigned int tx_fifo_width;
+ unsigned int fifo_bits;
+ unsigned long timeout_us = 10000;
+
+ baud = 115200;
+
+ if (priv) {
+ baud = priv->baud;
+ if (!baud)
+ baud = 115200;
+ tx_fifo_depth = geni_se_get_tx_fifo_depth(priv->base);
+ tx_fifo_width = geni_se_get_tx_fifo_width(priv->base);
+ fifo_bits = tx_fifo_depth * tx_fifo_width;
+ /*
+ * Total polling iterations based on FIFO worth of bytes to be
+ * sent at current baud. Add a little fluff to the wait.
+ */
+ timeout_us = ((fifo_bits * USEC_PER_SEC) / baud) + 500;
+ }
+
+ /*
+ * Use custom implementation instead of readl_poll_atomic since ktimer
+ * is not ready at the time of early console.
+ */
+ timeout_us = DIV_ROUND_UP(timeout_us, 10) * 10;
+ while (timeout_us) {
+ reg = readl(priv->base + offset);
+ if ((bool)(reg & field) == set)
+ return true;
+ udelay(10);
+ timeout_us -= 10;
+ }
+ return false;
+}
+
+static void qcom_geni_serial_setup_tx(u64 base, u32 xmit_size) {
+ u32 m_cmd;
+
+ writel(xmit_size, base + SE_UART_TX_TRANS_LEN);
+ m_cmd = UART_START_TX << M_OPCODE_SHIFT;
+ writel(m_cmd, base + SE_GENI_M_CMD0);
+}
+
+static inline void qcom_geni_serial_poll_tx_done(const struct udevice
*dev) {
+ struct msm_serial_data *priv = dev_get_priv(dev);
+ int done = 0;
+ u32 irq_clear = M_CMD_DONE_EN;
+
+ done = qcom_geni_serial_poll_bit(dev, SE_GENI_M_IRQ_STATUS,
+ M_CMD_DONE_EN, true);
+ if (!done) {
+ writel(M_GENI_CMD_ABORT, priv->base + SE_GENI_M_CMD_CTRL_REG);
+ irq_clear |= M_CMD_ABORT_EN;
+ qcom_geni_serial_poll_bit(dev, SE_GENI_M_IRQ_STATUS,
+  M_CMD_ABORT_EN, true);
+ }
+ writel(irq_clear, priv->base + SE_GENI_M_IRQ_CLEAR);
+}
+
+static u32 qcom_geni_serial_tx_empty(u64 base) {
+ return !readl(base + SE_GENI_TX_FIFO_STATUS);
+}
+
+/**
+ * geni_se_setup_s_cmd() - Setup the secondary sequencer
+ * @se: Pointer to the concerned serial engine.
+ * @cmd: Command/Operation to setup in the secondary sequencer.
+ * @params: Parameter for the sequencer command.
+ *
+ * This function is used to configure the secondary sequencer with the
+ * command and its associated parameters.
+ */
+static inline void geni_se_setup_s_cmd(u64 base, u32 cmd, u32 params) {
+ u32 s_cmd;
+
+ s_cmd = readl(base + SE_GENI_S_CMD0);
+ s_cmd &= ~(S_OPCODE_MSK | S_PARAMS_MSK);
+ s_cmd |= (cmd << S_OPCODE_SHFT);
+ s_cmd |= (params & S_PARAMS_MSK);
+ writel(s_cmd, base + SE_GENI_S_CMD0);
+}
+
+static void qcom_geni_serial_start_tx(u64 base) {
+ u32 irq_en;
+ u32 status;
+
+ status = readl(base + SE_GENI_STATUS);
+ if (status & M_GENI_CMD_ACTIVE)
+ return;
+
+ if (!qcom_geni_serial_tx_empty(base))
+ return;
+
+ irq_en = readl(base + SE_GENI_M_IRQ_EN);
+ irq_en |= M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN;
+
+ writel(DEF_TX_WM, base + SE_GENI_TX_WATERMARK_REG);
+ writel(irq_en, base + SE_GENI_M_IRQ_EN);
+}
+
+static void qcom_geni_serial_start_rx(struct udevice *dev) {
+ u32 irq_en;
+ u32 status;
+ struct msm_serial_data *priv = dev_get_priv(dev);
+
+ status = readl(priv->base + SE_GENI_STATUS);
+
+ geni_se_setup_s_cmd(priv->base, UART_START_READ, 0);
+
+ irq_en = readl(priv->base + SE_GENI_S_IRQ_EN);
+ irq_en |= S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN;
+ writel(irq_en, priv->base + SE_GENI_S_IRQ_EN);
+
+ irq_en = readl(priv->base + SE_GENI_M_IRQ_EN);
+ irq_en |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
+ writel(irq_en, priv->base + SE_GENI_M_IRQ_EN);
+}
+
+static void msm_geni_serial_setup_rx(struct udevice *dev) {
+ u32 irq_clear = S_CMD_DONE_EN;
+ u32 geni_s_irq_en;
+ u32 geni_m_irq_en;
+ u32 cfg0;
+ u32 cfg1;
+ struct msm_serial_data *priv = dev_get_priv(dev);
+
+ irq_clear |= S_CMD_ABORT_EN;
+
+ writel(S_GENI_CMD_ABORT, priv->base + SE_GENI_S_CMD_CTRL_REG);
+ qcom_geni_serial_poll_bit(dev, SE_GENI_S_CMD_CTRL_REG, S_GENI_CMD_ABORT,
+  false);
+ writel(irq_clear, priv->base + SE_GENI_S_IRQ_CLEAR);
+ writel(FORCE_DEFAULT, priv->base + GENI_FORCE_DEFAULT_REG);
+
+ cfg0 = 0xf;
+ cfg1 = 0x0;
+ writel(cfg0, priv->base + SE_GENI_RX_PACKING_CFG0);
+ writel(cfg1, priv->base + SE_GENI_RX_PACKING_CFG1);
+
+ geni_se_setup_s_cmd(priv->base, UART_START_READ, 0);
+
+ geni_s_irq_en = readl(priv->base + SE_GENI_S_IRQ_EN);
+ geni_m_irq_en = readl(priv->base + SE_GENI_M_IRQ_EN);
+
+ geni_s_irq_en |= S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN;
+ geni_m_irq_en |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
+
+ writel(geni_s_irq_en, priv->base + SE_GENI_S_IRQ_EN);
+ writel(geni_m_irq_en, priv->base + SE_GENI_M_IRQ_EN);
+}
+
+static int msm_serial_putc(struct udevice *dev, const char ch) {
+ struct msm_serial_data *priv = dev_get_priv(dev);
+
+ writel(DEF_TX_WM, priv->base + SE_GENI_TX_WATERMARK_REG);
+ qcom_geni_serial_setup_tx(priv->base, 1);
+
+ qcom_geni_serial_poll_bit(dev, SE_GENI_M_IRQ_STATUS,
+  M_TX_FIFO_WATERMARK_EN, true);
+
+ writel(ch, priv->base + SE_GENI_TX_FIFOn);
+ writel(M_TX_FIFO_WATERMARK_EN, priv->base + SE_GENI_M_IRQ_CLEAR);
+
+ qcom_geni_serial_poll_tx_done(dev);
+
+ return 0;
+}
+
+static int msm_serial_getc(struct udevice *dev) {
+ struct msm_serial_data *priv = dev_get_priv(dev);
+ u32 rx_fifo;
+ u32 m_irq_status;
+ u32 s_irq_status;
+
+ writel(1 << S_OPCODE_SHIFT, priv->base + SE_GENI_S_CMD0);
+
+ qcom_geni_serial_poll_bit(dev, SE_GENI_M_IRQ_STATUS, M_SEC_IRQ_EN,
+  true);
+
+ m_irq_status = readl(priv->base + SE_GENI_M_IRQ_STATUS);
+ s_irq_status = readl(priv->base + SE_GENI_S_IRQ_STATUS);
+ writel(m_irq_status, priv->base + SE_GENI_M_IRQ_CLEAR);
+ writel(s_irq_status, priv->base + SE_GENI_S_IRQ_CLEAR);
+ qcom_geni_serial_poll_bit(dev, SE_GENI_RX_FIFO_STATUS, RX_FIFO_WC_MSK,
+  true);
+
+ if (!readl(priv->base + SE_GENI_RX_FIFO_STATUS))
+ return 0;
+
+ rx_fifo = readl(priv->base + SE_GENI_RX_FIFOn);
+ return rx_fifo & 0xff;
+}
+
+static int msm_serial_pending(struct udevice *dev, bool input) {
+ struct msm_serial_data *priv = dev_get_priv(dev);
+
+ if (input)
+ return readl(priv->base + SE_GENI_RX_FIFO_STATUS) &
+       RX_FIFO_WC_MSK;
+ else
+ return readl(priv->base + SE_GENI_TX_FIFO_STATUS) &
+       TX_FIFO_WC_MSK;
+
+ return 0;
+}
+
+static const struct dm_serial_ops msm_serial_ops = {
+ .putc = msm_serial_putc,
+ .pending = msm_serial_pending,
+ .getc = msm_serial_getc,
+ .setbrg = msm_serial_setbrg,
+};
+
+static inline void geni_serial_init(phys_addr_t base_address) {
+ u32 tx_trans_cfg;
+ u32 tx_parity_cfg = 0; /* Disable Tx Parity */
+ u32 rx_trans_cfg = 0;
+ u32 rx_parity_cfg = 0; /* Disable Rx Parity */
+ u32 stop_bit_len = 0;  /* Default stop bit length - 1 bit */
+ u32 bits_per_char;
+
+ /*
+ * Ignore Flow control.
+ * n = 8.
+ */
+ tx_trans_cfg = UART_CTS_MASK;
+ bits_per_char = BITS_PER_BYTE;
+
+ u32 cfg0 = 0xf;
+
+ u32 cfg1 = 0x0;
+
+ /*
+ * Make an unconditional cancel on the main sequencer to reset
+ * it else we could end up in data loss scenarios.
+ */
+ writel(cfg0, base_address + SE_GENI_TX_PACKING_CFG0);
+ writel(cfg1, base_address + SE_GENI_TX_PACKING_CFG1);
+ writel(cfg0, base_address + SE_GENI_RX_PACKING_CFG0);
+ writel(cfg1, base_address + SE_GENI_RX_PACKING_CFG1);
+
+ writel(tx_trans_cfg, base_address + SE_UART_TX_TRANS_CFG);
+ writel(tx_parity_cfg, base_address + SE_UART_TX_PARITY_CFG);
+ writel(rx_trans_cfg, base_address + SE_UART_RX_TRANS_CFG);
+ writel(rx_parity_cfg, base_address + SE_UART_RX_PARITY_CFG);
+ writel(bits_per_char, base_address + SE_UART_TX_WORD_LEN);
+ writel(bits_per_char, base_address + SE_UART_RX_WORD_LEN);
+ writel(stop_bit_len, base_address + SE_UART_TX_STOP_BIT_LEN);
+}
+
+static int msm_serial_probe(struct udevice *dev) {
+ struct msm_serial_data *priv = dev_get_priv(dev);
+
+ /* No need to reinitialize the UART after relocation */
+ if (gd->flags & GD_FLG_RELOC)
+ return 0;
+
+ geni_serial_init(priv->base);
+ msm_geni_serial_setup_rx(dev);
+ qcom_geni_serial_start_rx(dev);
+ qcom_geni_serial_start_tx(priv->base);
+
+ pinctrl_select_state(dev, "uart");
+
+ return 0;
+}
+
+static int msm_serial_ofdata_to_platdata(struct udevice *dev) {
+ struct msm_serial_data *priv = dev_get_priv(dev);
+
+ priv->base = dev_read_addr(dev);
+ if (priv->base == FDT_ADDR_T_NONE)
+ return -EINVAL;
+
+ return 0;
+}
+
+static const struct udevice_id msm_serial_ids[] = {
+ {.compatible = "qcom,msm-geni-uart"}, {}};
+
+U_BOOT_DRIVER(serial_msm_geni) = {
+ .name = "serial_msm_geni",
+ .id = UCLASS_SERIAL,
+ .of_match = msm_serial_ids,
+ .of_to_plat = msm_serial_ofdata_to_platdata,
+ .priv_auto = sizeof(struct msm_serial_data),
+ .probe = msm_serial_probe,
+ .ops = &msm_serial_ops,
+};
+
+#ifdef CONFIG_DEBUG_UART_MSM_GENI
+
+static struct msm_serial_data init_serial_data = {
+ .base = CONFIG_DEBUG_UART_BASE
+};
+
+/* Serial dumb device, to reuse driver code */
+static struct udevice init_dev = {
+ .priv_ = &init_serial_data,
+};
+
+#include <debug_uart.h>
+
+static inline void _debug_uart_init(void) {
+ phys_addr_t base = CONFIG_DEBUG_UART_BASE;
+
+ geni_serial_init(base);
+ geni_serial_baud(base, CONFIG_DEBUG_UART_CLOCK, CONFIG_BAUDRATE);
+ qcom_geni_serial_start_tx(base);
+}
+
+static inline void _debug_uart_putc(int ch) {
+ phys_addr_t base = CONFIG_DEBUG_UART_BASE;
+
+ writel(DEF_TX_WM, base + SE_GENI_TX_WATERMARK_REG);
+ qcom_geni_serial_setup_tx(base, 1);
+ qcom_geni_serial_poll_bit(&init_dev, SE_GENI_M_IRQ_STATUS,
+  M_TX_FIFO_WATERMARK_EN, true);
+
+ writel(ch, base + SE_GENI_TX_FIFOn);
+ writel(M_TX_FIFO_WATERMARK_EN, base + SE_GENI_M_IRQ_CLEAR);
+ qcom_geni_serial_poll_tx_done(&init_dev);
+}
+
+DEBUG_UART_FUNCS
+
+#endif
-- 
2.20.1

Re: Subject: [PATCH 1/6 v2] serial: qcom: add support for GENI serial driver

[Minkyu Kang]

Dear Dzmitry Sankouski ,

On Tue, 31 Aug 2021 at 20:29, Дмитрий Санковский <dsankouski@gmail.com>
wrote:

> From b2516d965ee933bdb10fc158e36dedcf65bd7ce9 Mon Sep 17 00:00:00 2001
> From: Dzmitry Sankouski <dsankouski@gmail.com>
> Date: Fri, 27 Aug 2021 17:47:22 +0300
> Subject: [PATCH 1/6 v2] serial: qcom: add support for GENI serial driver
>
> Generic Interface (GENI) Serial Engine (SE) based uart
> can be found on newer qualcomm SOCs, starting from SDM845.
> Tested on Samsung SM-G9600(starqltechn)
> by chain-loading u-boot with stock bootloader.
>
> Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com>
> Cc: Ramon Fried <rfried.dev@gmail.com>
> ---
> Changes for v2:
> - change functions return type to void, where possible
> - remove '.' from summary line
>
>  MAINTAINERS                                   |   1 +
>  .../serial/msm-geni-serial.txt                |   6 +
>  drivers/serial/Kconfig                        |  17 +
>  drivers/serial/Makefile                       |   1 +
>  drivers/serial/serial_msm_geni.c              | 579 ++++++++++++++++++
>  5 files changed, 604 insertions(+)
>  create mode 100644 doc/device-tree-bindings/serial/msm-geni-serial.txt
>  create mode 100644 drivers/serial/serial_msm_geni.c
>
>
Please check the coding style first.
It will help you: CodingStyle < U-Boot < DENX
<https://www.denx.de/wiki/U-Boot/CodingStyle>

-- 
Thanks,
Minkyu Kang.