From: Kamal Dasu <kamal.dasu-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
To: Scott Branden <scott.branden-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
Cc: Kamal Dasu <kdasu.kdev-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
f.fainelli-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org,
bcm-kernel-feedback-list-dY08KVG/lbpWk0Htik3J/w@public.gmane.org,
Vikram Prakash
<vikram.prakash-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>,
Andy Fung <andy.fung-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>,
Jon Mason <jon.mason-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>,
Yendapally Reddy Dhananjaya Reddy
<yendapally.reddy-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
Subject: Re: [PATCH V2, 2/4] spi: bcm-qspi: Add SPI flash and MSPI driver
Date: Fri, 27 May 2016 16:42:12 -0400 [thread overview]
Message-ID: <CAKekbeufyY6SDN0SN_Pm+Bn+qeobr5=n3vTZEWEXkLyoQwiTvQ@mail.gmail.com> (raw)
In-Reply-To: <5748AE99.8050303-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
Will take care of the header and 'depends'.
Kamal
On Fri, May 27, 2016 at 4:31 PM, Scott Branden
<scott.branden-dY08KVG/lbpWk0Htik3J/w@public.gmane.org> wrote:
> Hi Kamal,
>
> A few comments.
>
> On 16-05-27 01:14 PM, Kamal Dasu wrote:
>>
>> Adding unified SPI flash and MSPI driver for Broadcom
>> BRCMSTB, NS2, NSP SoCs. Driver shall work with
>> brcm,7120-l2-intc or brcm-l2-intc or with a single
>> muxed L1 interrupt source. Driver implements the
>> queued transfer_one_message() method for reading
>> from and writing to spi device.
>>
>> Signed-off-by: Kamal Dasu <kdasu.kdev-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>> Signed-off-by: Yendapally Reddy Dhananjaya Reddy
>> <yendapally.reddy-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
>> ---
>> V2 Changes:
>> Implemented transfer_one_message() method, removed deprecated transfer()
>> method
>> Refactored MSPI hw read write code to handle spi transfers
>> Refactored BSPI reads to handle spi transfers
>> Better handling of LE and BE archtectures via register rw inline
>> functions
>> Removed all uneceesary code related to message queue handling
>> ---
>>
>> drivers/spi/Kconfig | 6 +
>> drivers/spi/Makefile | 1 +
>> drivers/spi/spi-bcm-qspi.c | 1841
>> ++++++++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 1848 insertions(+)
>> create mode 100644 drivers/spi/spi-bcm-qspi.c
>>
>> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
>> index 4b931ec..396f9a2 100644
>> --- a/drivers/spi/Kconfig
>> +++ b/drivers/spi/Kconfig
>> @@ -153,6 +153,12 @@ config SPI_BCM63XX_HSSPI
>> This enables support for the High Speed SPI controller present
>> on
>> newer Broadcom BCM63XX SoCs.
>>
>> +config SPI_BCM_QSPI
>> + tristate "Broadcom BSPI and MSPI controller support"
>
> depends on ARCH_BCM || COMPILE_TEST
>>
>> + help
>> + Enables support for the Broadcom SPI flash and MSPI controller.
>> + Currently supports BRCMSTB, NSP, NS2 SoCs
>> +
>> config SPI_BITBANG
>> tristate "Utilities for Bitbanging SPI masters"
>> help
>> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
>> index 3c74d00..2c356c7 100644
>> --- a/drivers/spi/Makefile
>> +++ b/drivers/spi/Makefile
>> @@ -21,6 +21,7 @@ obj-$(CONFIG_SPI_BCM2835AUX) +=
>> spi-bcm2835aux.o
>> obj-$(CONFIG_SPI_BCM53XX) += spi-bcm53xx.o
>> obj-$(CONFIG_SPI_BCM63XX) += spi-bcm63xx.o
>> obj-$(CONFIG_SPI_BCM63XX_HSSPI) += spi-bcm63xx-hsspi.o
>> +obj-$(CONFIG_SPI_BCM_QSPI) += spi-bcm-qspi.o
>> obj-$(CONFIG_SPI_BFIN5XX) += spi-bfin5xx.o
>> obj-$(CONFIG_SPI_ADI_V3) += spi-adi-v3.o
>> obj-$(CONFIG_SPI_BFIN_SPORT) += spi-bfin-sport.o
>> diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c
>> new file mode 100644
>> index 0000000..323a6d9
>> --- /dev/null
>> +++ b/drivers/spi/spi-bcm-qspi.c
>> @@ -0,0 +1,1841 @@
>> +/*
>> + * Copyright (C) 2014-2016 Broadcom
>> + *
>> + * Redistribution and use in source and binary forms, with or without
>> + * modification, are permitted provided that the following conditions
>> + * are met:
>> + * 1. Redistributions of source code must retain the above copyright
>> + * notice, this list of conditions and the following disclaimer.
>> + * 2. Redistributions in binary form must reproduce the above copyright
>> + * notice, this list of conditions and the following disclaimer in the
>> + * documentation and/or other materials provided with the
>> distribution.
>> + * 3. Neither the name of the project nor the names of its contributors
>> + * may be used to endorse or promote products derived from this
>> software
>> + * without specific prior written permission.
>> + *
>> + * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS''
>> AND
>> + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
>> + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
>> PURPOSE
>> + * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE
>> LIABLE
>> + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
>> CONSEQUENTIAL
>> + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
>> GOODS
>> + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
>> + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
>> STRICT
>> + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
>> WAY
>> + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
>> + * SUCH DAMAGE.
>> + */
>
> This file should have the standard Broadcom GPL header on it.
>
>> +
>> +#include <linux/clk.h>
>> +#include <linux/delay.h>
>> +#include <linux/device.h>
>> +#include <linux/init.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/io.h>
>> +#include <linux/ioport.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/mtd/cfi.h>
>> +#include <linux/mtd/spi-nor.h>
>> +#include <linux/of.h>
>> +#include <linux/of_irq.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/slab.h>
>> +#include <linux/spi/spi.h>
>> +#include <linux/sysfs.h>
>> +#include <linux/types.h>
>> +
>> +#define DRIVER_NAME "bcm_qspi"
>> +
>> +#define DBG(...) pr_debug(__VA_ARGS__)
>> +
>> +#define STATE_IDLE 0
>> +#define STATE_RUNNING 1
>> +#define STATE_SHUTDOWN 2
>> +
>> +/* BSPI register offsets */
>> +#define BSPI_REVISION_ID 0x000
>> +#define BSPI_SCRATCH 0x004
>> +#define BSPI_MAST_N_BOOT_CTRL 0x008
>> +#define BSPI_BUSY_STATUS 0x00c
>> +#define BSPI_INTR_STATUS 0x010
>> +#define BSPI_B0_STATUS 0x014
>> +#define BSPI_B0_CTRL 0x018
>> +#define BSPI_B1_STATUS 0x01c
>> +#define BSPI_B1_CTRL 0x020
>> +#define BSPI_STRAP_OVERRIDE_CTRL 0x024
>> +#define BSPI_FLEX_MODE_ENABLE 0x028
>> +#define BSPI_BITS_PER_CYCLE 0x02c
>> +#define BSPI_BITS_PER_PHASE 0x030
>> +#define BSPI_CMD_AND_MODE_BYTE 0x034
>> +#define BSPI_BSPI_FLASH_UPPER_ADDR_BYTE 0x038
>> +#define BSPI_BSPI_XOR_VALUE 0x03c
>> +#define BSPI_BSPI_XOR_ENABLE 0x040
>> +#define BSPI_BSPI_PIO_MODE_ENABLE 0x044
>> +#define BSPI_BSPI_PIO_IODIR 0x048
>> +#define BSPI_BSPI_PIO_DATA 0x04c
>> +
>> +/* RAF register offsets */
>> +#define BSPI_RAF_START_ADDR 0x100
>> +#define BSPI_RAF_NUM_WORDS 0x104
>> +#define BSPI_RAF_CTRL 0x108
>> +#define BSPI_RAF_FULLNESS 0x10c
>> +#define BSPI_RAF_WATERMARK 0x110
>> +#define BSPI_RAF_STATUS 0x114
>> +#define BSPI_RAF_READ_DATA 0x118
>> +#define BSPI_RAF_WORD_CNT 0x11c
>> +#define BSPI_RAF_CURR_ADDR 0x120
>> +
>> +/* MSPI register offsets */
>> +#define MSPI_SPCR0_LSB 0x000
>> +#define MSPI_SPCR0_MSB 0x004
>> +#define MSPI_SPCR1_LSB 0x008
>> +#define MSPI_SPCR1_MSB 0x00c
>> +#define MSPI_NEWQP 0x010
>> +#define MSPI_ENDQP 0x014
>> +#define MSPI_SPCR2 0x018
>> +#define MSPI_MSPI_STATUS 0x020
>> +#define MSPI_CPTQP 0x024
>> +#define MSPI_SPCR3 0x028
>> +#define MSPI_TXRAM 0x040
>> +#define MSPI_RXRAM 0x0c0
>> +#define MSPI_CDRAM 0x140
>> +#define MSPI_WRITE_LOCK 0x180
>> +
>> +#define MSPI_MASTER_BIT BIT(7)
>> +
>> +#define MSPI_NUM_CDRAM 16
>> +#define MSPI_CDRAM_CONT_BIT BIT(7)
>> +#define MSPI_CDRAM_BITSE_BIT BIT(6)
>> +#define MSPI_CDRAM_PCS 0xf
>> +
>> +#define MSPI_SPCR2_SPE BIT(6)
>> +#define MSPI_SPCR2_CONT_AFTER_CMD BIT(7)
>> +
>> +#define MSPI_MSPI_STATUS_SPIF BIT(0)
>> +
>> +#define BSPI_ADDRLEN_3BYTES 3
>> +#define BSPI_ADDRLEN_4BYTES 4
>> +
>> +#define BSPI_RAF_STATUS_FIFO_EMPTY_MASK BIT(1)
>> +
>> +#define BSPI_RAF_CTRL_START_MASK BIT(0)
>> +#define BSPI_RAF_CTRL_CLEAR_MASK BIT(1)
>> +
>> +#define BSPI_BPP_MODE_SELECT_MASK BIT(8)
>> +#define BSPI_BPP_ADDR_SELECT_MASK BIT(16)
>> +
>> +/* HIF INTR2 offsets */
>> +#define HIF_SPI_INTR2_CPU_STATUS 0x00
>> +#define HIF_SPI_INTR2_CPU_SET 0x04
>> +#define HIF_SPI_INTR2_CPU_CLEAR 0x08
>> +#define HIF_SPI_INTR2_CPU_MASK_STATUS 0x0c
>> +#define HIF_SPI_INTR2_CPU_MASK_SET 0x10
>> +#define HIF_SPI_INTR2_CPU_MASK_CLEAR 0x14
>> +
>> +#define INTR_BASE_BIT_SHIFT 0x02
>> +#define INTR_COUNT 0x07
>> +
>> +/* MSPI Interrupt masks */
>> +#define INTR_MSPI_HALTED_MASK BIT(6)
>> +#define INTR_MSPI_DONE_MASK BIT(5)
>> +
>> +/* BSPI interrupt masks */
>> +#define INTR_BSPI_LR_OVERREAD_MASK BIT(4)
>> +#define INTR_BSPI_LR_SESSION_DONE_MASK BIT(3)
>> +#define INTR_BSPI_LR_IMPATIENT_MASK BIT(2)
>> +#define INTR_BSPI_LR_SESSION_ABORTED_MASK BIT(1)
>> +#define INTR_BSPI_LR_FULLNESS_REACHED_MASK BIT(0)
>> +
>> +/* Override mode masks */
>> +#define BSPI_STRAP_OVERRIDE_CTRL_OVERRIDE BIT(0)
>> +#define BSPI_STRAP_OVERRIDE_CTRL_DATA_DUAL BIT(1)
>> +#define BSPI_STRAP_OVERRIDE_CTRL_ADDR_4BYTE BIT(2)
>> +#define BSPI_STRAP_OVERRIDE_CTRL_DATA_QUAD BIT(3)
>> +#define BSPI_STRAP_OVERRIDE_CTRL_ENDAIN_MODE BIT(4)
>> +
>> +#define MSPI_INTERRUPTS_ALL \
>> + (INTR_MSPI_DONE_MASK | \
>> + INTR_MSPI_HALTED_MASK)
>> +
>> +#define BSPI_LR_INTERRUPTS_DATA \
>> + (INTR_BSPI_LR_SESSION_DONE_MASK | \
>> + INTR_BSPI_LR_FULLNESS_REACHED_MASK)
>> +
>> +#define BSPI_LR_INTERRUPTS_ERROR \
>> + (INTR_BSPI_LR_OVERREAD_MASK | \
>> + INTR_BSPI_LR_IMPATIENT_MASK | \
>> + INTR_BSPI_LR_SESSION_ABORTED_MASK)
>> +
>> +#define BSPI_LR_INTERRUPTS_ALL \
>> + (BSPI_LR_INTERRUPTS_ERROR | \
>> + BSPI_LR_INTERRUPTS_DATA)
>> +
>> +#define QSPI_INTERRUPTS_ALL \
>> + (MSPI_INTERRUPTS_ALL | \
>> + BSPI_LR_INTERRUPTS_ALL)
>> +
>> +#define BSPI_FLASH_TYPE_UNKNOWN -1
>> +
>> +#define NUM_CHIPSELECT 4
>> +#define MSPI_BASE_FREQ 27000000UL
>> +#define QSPI_SPBR_MIN 8U
>> +#define QSPI_SPBR_MAX 255U
>> +#define MAX_SPEED_HZ (MSPI_BASE_FREQ / (QSPI_SPBR_MIN * 2))
>> +
>> +#define OPCODE_DIOR 0xBB
>> +#define OPCODE_QIOR 0xEB
>> +#define OPCODE_DIOR_4B 0xBC
>> +#define OPCODE_QIOR_4B 0xEC
>> +
>> +#define PARMS_NO_OVERRIDE 0
>> +#define PARMS_OVERRIDE 1
>> +
>> +#define DWORD_ALIGNED(a) IS_ALIGNED((uintptr_t)(a),
>> 4)
>> +#define ADDR_TO_4MBYTE_SEGMENT(addr) (((u32)(addr)) >> 22)
>> +
>> +static int bspi_flash = BSPI_FLASH_TYPE_UNKNOWN;
>> +
>> +struct bcm_qspi_parms {
>> + u32 speed_hz;
>> + u8 chip_select;
>> + u8 mode;
>> + u8 bits_per_word;
>> +};
>> +
>> +static const struct bcm_qspi_parms bcm_qspi_default_parms_cs0 = {
>> + .speed_hz = MAX_SPEED_HZ,
>> + .chip_select = 0,
>> + .mode = SPI_MODE_3,
>> + .bits_per_word = 8,
>> +};
>> +
>> +struct bcm_xfer_mode {
>> + bool flex_mode;
>> + unsigned int width;
>> + unsigned int addrlen;
>> + unsigned int hp;
>> +};
>> +
>> +enum base_type {
>> + MSPI,
>> + BSPI,
>> + INTR,
>> + INTR_STATUS,
>> + CHIP_SELECT,
>> + BASEMAX,
>> +};
>> +
>> +struct bcm_qspi_irq {
>> + const char *irq_name;
>> + const irq_handler_t irq_handler;
>> + u32 mask;
>> +};
>> +
>> +struct bcm_qspi_dev_id {
>> + const struct bcm_qspi_irq *irqp;
>> + void *dev;
>> +};
>> +
>> +struct position {
>> + struct spi_transfer *trans;
>> + int byte;
>> +};
>> +
>> +struct bcm_qspi {
>> + struct platform_device *pdev;
>> + struct spi_master *master;
>> + struct clk *clk;
>> + u32 base_clk;
>> + u32 max_speed_hz;
>> + void __iomem *base[BASEMAX];
>> + struct bcm_qspi_parms last_parms;
>> + struct position pos;
>> + int state;
>> + int next_udelay;
>> + int cs_change;
>> + int curr_cs;
>> + int bspi_maj_rev;
>> + int bspi_min_rev;
>> + int bspi_enabled;
>> + int bspi_cs_bmap;
>> + struct spi_transfer *bspi_xfer;
>> + u32 bspi_xfer_idx;
>> + u32 bspi_xfer_len;
>> + u32 bspi_xfer_status;
>> + u32 actual_length;
>> + struct bcm_xfer_mode xfer_mode;
>> + u32 s3_intr2_mask;
>> + u32 s3_strap_override_ctrl;
>> + bool hif_spi_mode;
>> + bool bspi_mode;
>> + int num_irqs;
>> + struct bcm_qspi_dev_id *dev_ids;
>> + struct completion mspi_done;
>> + struct completion bspi_done;
>> +};
>> +
>> +static inline bool has_bspi(struct bcm_qspi *qspi)
>> +{
>> + return qspi->bspi_mode;
>> +}
>> +
>> +/* Read qspi controller register*/
>> +static inline u32 bcm_qspi_read(struct bcm_qspi *qspi, enum base_type
>> type,
>> + unsigned int offset)
>> +{
>> + if (!qspi->base[type])
>> + return 0;
>> +
>> + /*
>> + * MIPS endianness is configured by boot strap, which also
>> reverses all
>> + * bus endianness (i.e., big-endian CPU + big endian bus ==>
>> native
>> + * endian I/O).
>> + *
>> + * Other architectures (e.g., ARM) either do not support big
>> endian, or
>> + * else leave I/O in little endian mode.
>> + */
>> + if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
>> + return __raw_readl(qspi->base[type] + offset);
>> + else
>> + return readl_relaxed(qspi->base[type] + offset);
>> +
>> +}
>> +
>> +/* Write qspi controller register*/
>> +static inline void bcm_qspi_write(struct bcm_qspi *qspi, enum base_type
>> type,
>> + unsigned int offset, unsigned int data)
>> +{
>> + if (!qspi->base[type])
>> + return;
>> +
>> + /* See brcm_mspi_readl() comments */
>> + if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
>> + __raw_writel(data, (qspi->base[type] + offset));
>> + else
>> + writel_relaxed(data, (qspi->base[type] + offset));
>> +}
>> +
>> +static void bcm_qspi_enable_interrupt(struct bcm_qspi *qspi, u32 mask)
>> +{
>> + unsigned int val;
>> +
>> + if (!qspi->base[INTR])
>> + return;
>> +
>> + if (qspi->hif_spi_mode)
>> + bcm_qspi_write(qspi, INTR, HIF_SPI_INTR2_CPU_MASK_CLEAR,
>> mask);
>> + else {
>> + val = bcm_qspi_read(qspi, INTR, 0);
>> + val = val | (mask << INTR_BASE_BIT_SHIFT);
>> + bcm_qspi_write(qspi, INTR, 0, val);
>> + }
>> +}
>> +
>> +static void bcm_qspi_disable_interrupt(struct bcm_qspi *qspi, u32 mask)
>> +{
>> + unsigned int val;
>> +
>> + if (!qspi->base[INTR])
>> + return;
>> +
>> + if (qspi->hif_spi_mode)
>> + bcm_qspi_write(qspi, INTR, HIF_SPI_INTR2_CPU_MASK_SET,
>> mask);
>> + else {
>> + val = bcm_qspi_read(qspi, INTR, 0);
>> + val = val & ~(mask << INTR_BASE_BIT_SHIFT);
>> + bcm_qspi_write(qspi, INTR, 0, val);
>> + }
>> +}
>> +
>> +static void bcm_qspi_clear_interrupt(struct bcm_qspi *qspi, u32 mask)
>> +{
>> + unsigned int val;
>> +
>> + if (!qspi->base[INTR_STATUS])
>> + return;
>> +
>> + if (qspi->hif_spi_mode)
>> + bcm_qspi_write(qspi, INTR_STATUS,
>> + HIF_SPI_INTR2_CPU_CLEAR, mask);
>> + else {
>> + for (val = 0; val < INTR_COUNT; val++) {
>> + if (mask & (1UL << val))
>> + bcm_qspi_write(qspi, INTR_STATUS,
>> + (val * 4), 1);
>> + }
>> + }
>> +}
>> +
>> +static u32 bcm_qspi_read_l2int_status(struct bcm_qspi *qspi)
>> +{
>> + unsigned int val = 0;
>> + unsigned int i = 0;
>> +
>> + BUG_ON(!qspi->base[INTR_STATUS]);
>> +
>> + if (qspi->hif_spi_mode)
>> + val = bcm_qspi_read(qspi, INTR_STATUS,
>> + HIF_SPI_INTR2_CPU_STATUS);
>> + else {
>> + for (i = 0; i < INTR_COUNT; i++) {
>> + if (bcm_qspi_read(qspi, INTR_STATUS, (i * 4)))
>> + val |= 1UL << i;
>> + }
>> + }
>> + return val;
>> +}
>> +
>> +static int bcm_qspi_bspi_busy_poll(struct bcm_qspi *qspi)
>> +{
>> + int i;
>> +
>> + /* this should normally finish within 10us */
>> + for (i = 0; i < 1000; i++) {
>> + if (!(bcm_qspi_read(qspi, BSPI, BSPI_BUSY_STATUS) & 1))
>> + return 0;
>> + udelay(1);
>> + }
>> + dev_warn(&qspi->pdev->dev, "timeout waiting for !busy_status\n");
>> + return -EIO;
>> +}
>> +
>> +static inline bool bcm_qspi_bspi_ver_three(struct bcm_qspi *qspi)
>> +{
>> + if (qspi->bspi_maj_rev < 4)
>> + return true;
>> + return false;
>> +}
>> +
>> +static void bcm_qspi_flush_prefetch_buffers(struct bcm_qspi *qspi)
>> +{
>> + bcm_qspi_bspi_busy_poll(qspi);
>> + /* Force rising edge for the b0/b1 'flush' field */
>> + bcm_qspi_write(qspi, BSPI, BSPI_B0_CTRL, 1);
>> + bcm_qspi_write(qspi, BSPI, BSPI_B1_CTRL, 1);
>> + bcm_qspi_write(qspi, BSPI, BSPI_B0_CTRL, 0);
>> + bcm_qspi_write(qspi, BSPI, BSPI_B1_CTRL, 0);
>> +}
>> +
>> +static int bcm_qspi_lr_is_fifo_empty(struct bcm_qspi *qspi)
>> +{
>> + return (bcm_qspi_read(qspi, BSPI, BSPI_RAF_STATUS) &
>> + BSPI_RAF_STATUS_FIFO_EMPTY_MASK);
>> +}
>> +
>> +static inline u32 bcm_qspi_lr_read_fifo(struct bcm_qspi *qspi)
>> +{
>> + u32 data = bcm_qspi_read(qspi, BSPI, BSPI_RAF_READ_DATA);
>> +
>> + /* BSPI v3 LR is LE only, convert data to host endianness */
>> + if (bcm_qspi_bspi_ver_three(qspi))
>> + data = le32_to_cpu(data);
>> +
>> + return data;
>> +}
>> +
>> +static inline void bcm_qspi_lr_start(struct bcm_qspi *qspi)
>> +{
>> + bcm_qspi_bspi_busy_poll(qspi);
>> + bcm_qspi_write(qspi, BSPI, BSPI_RAF_CTRL,
>> + BSPI_RAF_CTRL_START_MASK);
>> +}
>> +
>> +static inline void bcm_qspi_lr_clear(struct bcm_qspi *qspi)
>> +{
>> + bcm_qspi_write(qspi, BSPI, BSPI_RAF_CTRL,
>> + BSPI_RAF_CTRL_CLEAR_MASK);
>> + bcm_qspi_flush_prefetch_buffers(qspi);
>> +}
>> +
>> +static void bcm_qspi_bspi_lr_data_read(struct bcm_qspi *qspi)
>> +{
>> + u32 *buf = (u32 *)qspi->bspi_xfer->rx_buf;
>> + u32 data = 0;
>> +
>> + DBG("xfer %p rx %p rxlen %d\n",
>> + qspi->bspi_xfer, qspi->bspi_xfer->rx_buf,
>> qspi->bspi_xfer_len);
>> + while (!bcm_qspi_lr_is_fifo_empty(qspi)) {
>> + data = bcm_qspi_lr_read_fifo(qspi);
>> + if (likely(qspi->bspi_xfer_len >= 4) &&
>> + likely(DWORD_ALIGNED(buf))) {
>> + buf[qspi->bspi_xfer_idx++] = data;
>> + qspi->bspi_xfer_len -= 4;
>> + } else {
>> + /* Read out remaining bytes, make sure*/
>> + u8 *cbuf = (u8 *)&buf[qspi->bspi_xfer_idx];
>> +
>> + data = cpu_to_le32(data);
>> + while (qspi->bspi_xfer_len) {
>> + *cbuf++ = (u8)data;
>> + data >>= 8;
>> + qspi->bspi_xfer_len--;
>> + }
>> + }
>> + }
>> +}
>> +
>> +static inline int bcm_qspi_is_4_byte_mode(struct bcm_qspi *qspi)
>> +{
>> + return qspi->xfer_mode.addrlen == BSPI_ADDRLEN_4BYTES;
>> +}
>> +
>> +static void bcm_qspi_bspi_set_xfer_params(struct bcm_qspi *qspi, u8
>> cmd_byte,
>> + int bpp, int bpc, int flex_mode)
>> +{
>> + bcm_qspi_write(qspi, BSPI, BSPI_FLEX_MODE_ENABLE, 0);
>> + bcm_qspi_write(qspi, BSPI, BSPI_BITS_PER_CYCLE, bpc);
>> + bcm_qspi_write(qspi, BSPI, BSPI_BITS_PER_PHASE, bpp);
>> + bcm_qspi_write(qspi, BSPI, BSPI_CMD_AND_MODE_BYTE, cmd_byte);
>> + bcm_qspi_write(qspi, BSPI, BSPI_FLEX_MODE_ENABLE, flex_mode);
>> +}
>> +
>> +static int bcm_qspi_bspi_set_flex_mode(struct bcm_qspi *qspi, int width,
>> + int addrlen, int hp)
>> +{
>> + int bpc = 0, bpp = 0;
>> + u8 command = SPINOR_OP_READ_FAST;
>> + int flex_mode = 1, rv = 0;
>> + bool spans_4byte = false;
>> +
>> + DBG("set flex mode w %x addrlen %x hp %d\n", width, addrlen, hp);
>> +
>> + if (addrlen == BSPI_ADDRLEN_4BYTES) {
>> + bpp = BSPI_BPP_ADDR_SELECT_MASK;
>> + spans_4byte = true;
>> + }
>> +
>> + bpp |= 8; /* dummy cycles */
>> +
>> + switch (width) {
>> + case SPI_NBITS_SINGLE:
>> + if (addrlen == BSPI_ADDRLEN_3BYTES)
>> + /* default mode, does not need flex_cmd */
>> + flex_mode = 0;
>> + else
>> + command = SPINOR_OP_READ4_FAST;
>> + break;
>> + case SPI_NBITS_DUAL:
>> + bpc = 0x00000001;
>> + if (hp) {
>> + bpc |= 0x00010100; /* address and mode are 2-bit
>> */
>> + bpp = BSPI_BPP_MODE_SELECT_MASK;
>> + command = OPCODE_DIOR;
>> + if (spans_4byte == true)
>> + command = OPCODE_DIOR_4B;
>> + } else {
>> + command = SPINOR_OP_READ_1_1_2;
>> + if (spans_4byte == true)
>> + command = SPINOR_OP_READ4_1_1_2;
>> + }
>> + break;
>> + case SPI_NBITS_QUAD:
>> + bpc = 0x00000002;
>> + if (hp) {
>> + bpc |= 0x00020200; /* address and mode are 4-bit
>> */
>> + bpp = 4; /* dummy cycles */
>> + bpp |= BSPI_BPP_ADDR_SELECT_MASK;
>> + command = OPCODE_QIOR;
>> + if (spans_4byte == true)
>> + command = OPCODE_QIOR_4B;
>> + } else {
>> + command = SPINOR_OP_READ_1_1_4;
>> + if (spans_4byte == true)
>> + command = SPINOR_OP_READ4_1_1_4;
>> + }
>> + break;
>> + default:
>> + rv = -1;
>> + break;
>> + }
>> +
>> + if (!rv)
>> + bcm_qspi_bspi_set_xfer_params(qspi, command, bpp, bpc,
>> + flex_mode);
>> +
>> + return rv;
>> +}
>> +
>> +static int bcm_qspi_bspi_set_override(struct bcm_qspi *qspi, int width,
>> + int addrlen, int hp)
>> +{
>> + u32 data = bcm_qspi_read(qspi, BSPI, BSPI_STRAP_OVERRIDE_CTRL);
>> +
>> + DBG("set override mode w %x addrlen %x hp %d\n", width, addrlen,
>> hp);
>> +
>> + switch (width) {
>> + case SPI_NBITS_QUAD:
>> + /* clear dual mode and set quad mode */
>> + data &= ~BSPI_STRAP_OVERRIDE_CTRL_DATA_DUAL;
>> + data |= BSPI_STRAP_OVERRIDE_CTRL_DATA_QUAD;
>> + break;
>> + case SPI_NBITS_DUAL:
>> + /* clear quad mode set dual mode */
>> + data &= ~BSPI_STRAP_OVERRIDE_CTRL_DATA_QUAD;
>> + data |= BSPI_STRAP_OVERRIDE_CTRL_DATA_DUAL;
>> + break;
>> + case SPI_NBITS_SINGLE:
>> + /* clear quad/dual mode */
>> + data &= ~(BSPI_STRAP_OVERRIDE_CTRL_DATA_QUAD |
>> + BSPI_STRAP_OVERRIDE_CTRL_DATA_DUAL);
>> + break;
>> + default:
>> + break;
>> + }
>> +
>> + if (addrlen == BSPI_ADDRLEN_4BYTES)
>> + /* set 4byte mode*/
>> + data |= BSPI_STRAP_OVERRIDE_CTRL_ADDR_4BYTE;
>> + else
>> + /* clear 4 byte mode */
>> + data &= ~BSPI_STRAP_OVERRIDE_CTRL_ADDR_4BYTE;
>> +
>> + /* set the override mode */
>> + data |= BSPI_STRAP_OVERRIDE_CTRL_OVERRIDE;
>> + bcm_qspi_write(qspi, BSPI, BSPI_STRAP_OVERRIDE_CTRL, data);
>> + bcm_qspi_bspi_set_xfer_params(qspi, SPINOR_OP_READ_FAST, 0, 0, 0);
>> +
>> + return 0;
>> +}
>> +
>> +static void bcm_qspi_bspi_set_mode(struct bcm_qspi *qspi,
>> + int width, int addrlen, int hp)
>> +{
>> + int error = 0;
>> +
>> + if (width == -1)
>> + width = qspi->xfer_mode.width;
>> + if (addrlen == -1)
>> + addrlen = qspi->xfer_mode.addrlen;
>> + if (hp == -1)
>> + hp = qspi->xfer_mode.hp;
>> +
>> + /* default mode */
>> + qspi->xfer_mode.flex_mode = true;
>> +
>> + if (!bcm_qspi_bspi_ver_three(qspi)) {
>> + u32 val, mask;
>> +
>> + val = bcm_qspi_read(qspi, BSPI, BSPI_STRAP_OVERRIDE_CTRL);
>> + mask = BSPI_STRAP_OVERRIDE_CTRL_OVERRIDE;
>> + if (val & mask || qspi->s3_strap_override_ctrl & mask) {
>> + qspi->xfer_mode.flex_mode = false;
>> + bcm_qspi_write(qspi, BSPI, BSPI_FLEX_MODE_ENABLE,
>> + 0);
>> +
>> + if ((val | qspi->s3_strap_override_ctrl) &
>> + BSPI_STRAP_OVERRIDE_CTRL_DATA_DUAL)
>> + width = SPI_NBITS_DUAL;
>> + else if ((val | qspi->s3_strap_override_ctrl) &
>> + BSPI_STRAP_OVERRIDE_CTRL_DATA_QUAD)
>> + width = SPI_NBITS_QUAD;
>> +
>> + error = bcm_qspi_bspi_set_override(qspi, width,
>> addrlen,
>> + hp);
>> + }
>> + }
>> +
>> + if (qspi->xfer_mode.flex_mode)
>> + error = bcm_qspi_bspi_set_flex_mode(qspi, width, addrlen,
>> hp);
>> +
>> + if (!error) {
>> + qspi->xfer_mode.width = width;
>> + qspi->xfer_mode.addrlen = addrlen;
>> + qspi->xfer_mode.hp = hp;
>> + dev_info(&qspi->pdev->dev,
>> + "%d-lane output, %d-byte address%s\n",
>> + qspi->xfer_mode.width,
>> + qspi->xfer_mode.addrlen,
>> + qspi->xfer_mode.hp ? ", high-performance mode" :
>> "");
>> + } else
>> + dev_warn(&qspi->pdev->dev,
>> + "INVALID COMBINATION: width=%d addrlen=%d
>> hp=%d\n",
>> + width, addrlen, hp);
>> +}
>> +
>> +static void bcm_qspi_chip_select(struct bcm_qspi *qspi, int cs)
>> +{
>> + u32 data = 0;
>> +
>> + if (qspi->curr_cs == cs)
>> + return;
>> + if (qspi->base[CHIP_SELECT]) {
>> + data = bcm_qspi_read(qspi, CHIP_SELECT, 0);
>> + data = (data & ~0xff) | (1 << cs);
>> + bcm_qspi_write(qspi, CHIP_SELECT, 0, data);
>> + udelay(10);
>> + }
>> + qspi->curr_cs = cs;
>> +}
>> +
>> +static inline int bcm_qspi_bspi_cs(struct bcm_qspi *qspi, u8 cs)
>> +{
>> + return qspi->bspi_cs_bmap & (1 << cs);
>> +}
>> +
>> +static void bcm_qspi_enable_bspi(struct bcm_qspi *qspi)
>> +{
>> +
>> + if ((!qspi->base[BSPI]) || (qspi->bspi_enabled))
>> + return;
>> +
>> + qspi->bspi_enabled = 1;
>> + if ((bcm_qspi_read(qspi, BSPI, BSPI_MAST_N_BOOT_CTRL) & 1) == 0)
>> + return;
>> +
>> + bcm_qspi_flush_prefetch_buffers(qspi);
>> + udelay(1);
>> + bcm_qspi_write(qspi, BSPI, BSPI_MAST_N_BOOT_CTRL, 0);
>> + udelay(1);
>> +}
>> +
>> +static void bcm_qspi_disable_bspi(struct bcm_qspi *qspi)
>> +{
>> + if ((!qspi->base[BSPI]) || (!qspi->bspi_enabled))
>> + return;
>> +
>> + qspi->bspi_enabled = 0;
>> + if ((bcm_qspi_read(qspi, BSPI, BSPI_MAST_N_BOOT_CTRL) & 1))
>> + return;
>> +
>> + bcm_qspi_bspi_busy_poll(qspi);
>> + bcm_qspi_write(qspi, BSPI, BSPI_MAST_N_BOOT_CTRL, 1);
>> + udelay(1);
>> +}
>> +
>> +static void bcm_qspi_hw_set_parms(struct bcm_qspi *qspi,
>> + const struct bcm_qspi_parms *xp)
>> +{
>> + u32 spcr, spbr = 0;
>> +
>> + if (xp->speed_hz)
>> + spbr = qspi->base_clk / (2 * xp->speed_hz);
>> +
>> + spcr = clamp_val(spbr, QSPI_SPBR_MIN, QSPI_SPBR_MAX);
>> + bcm_qspi_write(qspi, MSPI, MSPI_SPCR0_LSB, spcr);
>> +
>> + spcr = MSPI_MASTER_BIT;
>> + /* for 16 bit the data should be zero */
>> + if (xp->bits_per_word != 16)
>> + spcr |= xp->bits_per_word << 2;
>> + spcr |= xp->mode & 3;
>> + bcm_qspi_write(qspi, MSPI, MSPI_SPCR0_MSB, spcr);
>> +
>> + qspi->last_parms = *xp;
>> +}
>> +
>> +static int bcm_qspi_update_parms(struct bcm_qspi *qspi,
>> + struct spi_device *spidev,
>> + struct spi_transfer *trans, int override)
>> +{
>> + struct bcm_qspi_parms xp;
>> +
>> + xp.speed_hz = min(trans->speed_hz ? trans->speed_hz :
>> + (spidev->max_speed_hz ? spidev->max_speed_hz :
>> + qspi->max_speed_hz), qspi->max_speed_hz);
>> + xp.chip_select = spidev->chip_select;
>> + xp.mode = spidev->mode;
>> + xp.bits_per_word = trans->bits_per_word ? trans->bits_per_word :
>> + (spidev->bits_per_word ? spidev->bits_per_word : 8);
>> +
>> + if ((override == PARMS_OVERRIDE) ||
>> + ((xp.speed_hz == qspi->last_parms.speed_hz) &&
>> + (xp.chip_select == qspi->last_parms.chip_select) &&
>> + (xp.mode == qspi->last_parms.mode) &&
>> + (xp.bits_per_word == qspi->last_parms.bits_per_word))) {
>> + bcm_qspi_hw_set_parms(qspi, &xp);
>> + return 0;
>> + }
>> + /* no override, and parms do not match */
>> + return 1;
>> +}
>> +
>> +static int bcm_qspi_setup(struct spi_device *spi)
>> +{
>> + struct bcm_qspi_parms *xp;
>> +
>> + if (spi->bits_per_word > 16)
>> + return -EINVAL;
>> +
>> + xp = spi_get_ctldata(spi);
>> + if (!xp) {
>> + xp = kzalloc(sizeof(struct bcm_qspi_parms), GFP_KERNEL);
>> + if (!xp)
>> + return -ENOMEM;
>> + spi_set_ctldata(spi, xp);
>> + }
>> + xp->speed_hz = spi->max_speed_hz;
>> + xp->chip_select = spi->chip_select;
>> + xp->mode = spi->mode;
>> + xp->bits_per_word = spi->bits_per_word ? spi->bits_per_word : 8;
>> +
>> + return 0;
>> +}
>> +
>> +/* MSPI helpers */
>> +
>> +/* stop at end of transfer, no other reason */
>> +#define FNB_BREAK_NONE 0
>> +/* stop at end of spi_message */
>> +#define FNB_BREAK_EOM 1
>> +/* stop at end of spi_transfer if delay */
>> +#define FNB_BREAK_DELAY 2
>> +/* stop at end of spi_transfer if cs_change */
>> +#define FNB_BREAK_CS_CHANGE 4
>> +/* stop if we run out of bytes */
>> +#define FNB_BREAK_NO_BYTES 8
>> +
>> +/* events that make us stop filling TX slots */
>> +#define FNB_BREAK_TX (FNB_BREAK_EOM | FNB_BREAK_DELAY |
>> \
>> + FNB_BREAK_CS_CHANGE)
>> +
>> +/* events that make us deassert CS */
>> +#define FNB_BREAK_DESELECT (FNB_BREAK_EOM |
>> FNB_BREAK_CS_CHANGE)
>> +
>> +static int find_next_byte(struct bcm_qspi *qspi, struct position *p,
>> + int flags)
>> +{
>> + int ret = FNB_BREAK_NONE;
>> +
>> + if (p->trans->bits_per_word <= 8)
>> + p->byte++;
>> + else
>> + p->byte += 2;
>> +
>> + if (p->byte >= p->trans->len) {
>> + /* we're at the end of the spi_transfer */
>> +
>> + /* in TX mode, need to pause for a delay or CS change */
>> + if (p->trans->delay_usecs && (flags & FNB_BREAK_DELAY))
>> + ret |= FNB_BREAK_DELAY;
>> + if (p->trans->cs_change && (flags & FNB_BREAK_CS_CHANGE))
>> + ret |= FNB_BREAK_CS_CHANGE;
>> + if (ret)
>> + goto done;
>> +
>> + DBG("find_next_byte: advance msg exit\n");
>> + if (spi_transfer_is_last(qspi->master, p->trans))
>> + ret = FNB_BREAK_EOM;
>> + else
>> + ret = FNB_BREAK_NO_BYTES;
>> +
>> + p->trans = NULL;
>> + }
>> +
>> +done:
>> + DBG("find_next_byte: trans %p len %d byte %d ret %x\n",
>> + p->trans, p->trans ? p->trans->len : 0, p->byte, ret);
>> + return ret;
>> +}
>> +
>> +static inline u8 read_rxram_slot_u8(struct bcm_qspi *qspi, int slot)
>> +{
>> + u32 slot_offset = MSPI_RXRAM + (slot << 3) + 0x4;
>> +
>> + /* mask out reserved bits */
>> + return bcm_qspi_read(qspi, MSPI, slot_offset) & 0xff;
>> +}
>> +
>> +static inline u16 read_rxram_slot_u16(struct bcm_qspi *qspi, int slot)
>> +{
>> + u32 reg_offset = MSPI_RXRAM;
>> + u32 lsb_offset = reg_offset + (slot << 3) + 0x4;
>> + u32 msb_offset = reg_offset + (slot << 3);
>> +
>> + return (bcm_qspi_read(qspi, MSPI, lsb_offset) & 0xff) |
>> + ((bcm_qspi_read(qspi, MSPI, msb_offset) & 0xff) << 8);
>> +}
>> +
>> +static void read_from_hw(struct bcm_qspi *qspi, int slots)
>> +{
>> + struct position p;
>> + int slot;
>> +
>> + bcm_qspi_disable_bspi(qspi);
>> +
>> + if (slots > MSPI_NUM_CDRAM) {
>> + /* should never happen */
>> + dev_err(&qspi->pdev->dev, "%s: too many slots!\n",
>> __func__);
>> + return;
>> + }
>> +
>> + p = qspi->pos;
>> +
>> + for (slot = 0; slot < slots; slot++) {
>> + if (p.trans->bits_per_word <= 8) {
>> + u8 *buf = p.trans->rx_buf;
>> +
>> + if (buf)
>> + buf[p.byte] = read_rxram_slot_u8(qspi,
>> slot);
>> + DBG("RD %02x\n", buf ? buf[p.byte] : 0xff);
>> + } else {
>> + u16 *buf = p.trans->rx_buf;
>> +
>> + if (buf)
>> + buf[p.byte / 2] =
>> read_rxram_slot_u16(qspi,
>> +
>> slot);
>> + DBG("RD %04x\n", buf ? buf[p.byte] : 0xffff);
>> + }
>> +
>> + find_next_byte(qspi, &p, FNB_BREAK_NONE);
>> + }
>> +
>> + qspi->pos = p;
>> +}
>> +
>> +static inline void write_txram_slot_u8(struct bcm_qspi *qspi, int slot,
>> + u8 val)
>> +{
>> + u32 reg_offset = MSPI_TXRAM + (slot << 3);
>> +
>> + /* mask out reserved bits */
>> + bcm_qspi_write(qspi, MSPI, reg_offset, val);
>> +}
>> +
>> +static inline void write_txram_slot_u16(struct bcm_qspi *qspi, int slot,
>> + u16 val)
>> +{
>> + u32 reg_offset = MSPI_TXRAM;
>> + u32 msb_offset = reg_offset + (slot << 3);
>> + u32 lsb_offset = reg_offset + (slot << 3) + 0x4;
>> +
>> + bcm_qspi_write(qspi, MSPI, msb_offset, (val >> 8));
>> + bcm_qspi_write(qspi, MSPI, lsb_offset, (val & 0xff));
>> +}
>> +
>> +static inline u32 read_cdram_slot(struct bcm_qspi *qspi, int slot)
>> +{
>> + return bcm_qspi_read(qspi, MSPI, MSPI_CDRAM + (slot << 2));
>> +}
>> +
>> +static inline void write_cdram_slot(struct bcm_qspi *qspi, int slot, u32
>> val)
>> +{
>> + bcm_qspi_write(qspi, MSPI, (MSPI_CDRAM + (slot << 2)), val);
>> +}
>> +
>> +/* Return number of slots written */
>> +static int write_to_hw(struct bcm_qspi *qspi, struct spi_device *spidev)
>> +{
>> + struct position p;
>> + int slot = 0, fnb = 0;
>> + u32 mspi_cdram = 0;
>> +
>> + bcm_qspi_disable_bspi(qspi);
>> + p = qspi->pos;
>> + bcm_qspi_update_parms(qspi, spidev, p.trans, PARMS_OVERRIDE);
>> +
>> + /* Run until end of transfer or reached the max data */
>> + while (!fnb && slot < MSPI_NUM_CDRAM) {
>> + if (p.trans->bits_per_word <= 8) {
>> + const u8 *buf = p.trans->tx_buf;
>> + u8 val = buf ? buf[p.byte] : 0xff;
>> +
>> + write_txram_slot_u8(qspi, slot, val);
>> + DBG("WR %02x\n", val);
>> + } else {
>> + const u16 *buf = p.trans->tx_buf;
>> + u16 val = buf ? buf[p.byte / 2] : 0xffff;
>> +
>> + write_txram_slot_u16(qspi, slot, val);
>> + DBG("WR %04x\n", val);
>> + }
>> + mspi_cdram = MSPI_CDRAM_CONT_BIT;
>> + mspi_cdram |= (~(1 << spidev->chip_select) &
>> + MSPI_CDRAM_PCS);
>> + mspi_cdram |= ((p.trans->bits_per_word <= 8) ? 0 :
>> + MSPI_CDRAM_BITSE_BIT);
>> +
>> + write_cdram_slot(qspi, slot, mspi_cdram);
>> +
>> + /* NOTE: This can update p.trans */
>> + fnb = find_next_byte(qspi, &p, FNB_BREAK_TX);
>> + slot++;
>> + }
>> + if (!slot) {
>> + dev_err(&qspi->pdev->dev, "%s: no data to send?",
>> __func__);
>> + goto done;
>> + }
>> +
>> + /* in TX mode, need to pause for a delay or CS change */
>> + if (fnb & FNB_BREAK_CS_CHANGE)
>> + qspi->cs_change = 1;
>> + if (fnb & FNB_BREAK_DELAY)
>> + qspi->next_udelay = p.trans->delay_usecs;
>> +
>> + DBG("submitting %d slots\n", slot);
>> + bcm_qspi_write(qspi, MSPI, MSPI_NEWQP, 0);
>> + bcm_qspi_write(qspi, MSPI, MSPI_ENDQP, slot - 1);
>> +
>> + /* deassert CS on the final byte */
>> + if (fnb & FNB_BREAK_DESELECT) {
>> + mspi_cdram = read_cdram_slot(qspi, slot - 1) &
>> + ~MSPI_CDRAM_CONT_BIT;
>> + write_cdram_slot(qspi, slot - 1, mspi_cdram);
>> + }
>> +
>> + if (has_bspi(qspi))
>> + bcm_qspi_write(qspi, MSPI, MSPI_WRITE_LOCK, 1);
>> +
>> + /* Must flush previous writes before starting MSPI operation */
>> + mb();
>> + /* Set cont | spe | spifie */
>> + bcm_qspi_write(qspi, MSPI, MSPI_SPCR2, 0xe0);
>> + qspi->state = STATE_RUNNING;
>> +
>> +done:
>> + return slot;
>> +}
>> +
>> +static void hw_stop(struct bcm_qspi *qspi)
>> +{
>> + if (has_bspi(qspi))
>> + bcm_qspi_write(qspi, MSPI, MSPI_WRITE_LOCK, 0);
>> + qspi->state = STATE_IDLE;
>> +}
>> +
>> +/* BSPI helpers */
>> +static int bcm_qspi_emulate_flash_read(struct bcm_qspi *qspi,
>> + struct spi_device *spi, struct spi_transfer
>> *t)
>> +{
>> + u32 addr, len, len_words;
>> + u8 *buf;
>> + int idx;
>> + struct spi_transfer *trans;
>> + int ret = 0;
>> + int retry = 3;
>> + unsigned long timeo = msecs_to_jiffies(100);
>> +
>> + if (bcm_qspi_bspi_ver_three(qspi))
>> + if (bcm_qspi_is_4_byte_mode(qspi))
>> + return -1;
>> +
>> + bcm_qspi_chip_select(qspi, spi->chip_select);
>> + /* first transfer - OPCODE_READ + {3,4}-byte address */
>> + trans = t;
>> + buf = (void *)trans->tx_buf;
>> +
>> + if (!buf) {
>> + ret = -EIO;
>> + goto out;
>> + }
>> +
>> + idx = 1;
>> + if (bcm_qspi_bspi_ver_three(qspi) == false) {
>> + if (bcm_qspi_is_4_byte_mode(qspi))
>> + addr = buf[idx++] << 24;
>> + else
>> + addr = 0;
>> + bcm_qspi_write(qspi, BSPI,
>> + BSPI_BSPI_FLASH_UPPER_ADDR_BYTE, addr);
>> + }
>> +
>> + addr = (buf[idx] << 16) | (buf[idx+1] << 8) | buf[idx+2];
>> +
>> + /*
>> + * when using override mode we need to send
>> + * the upper address byte to mspi
>> + */
>> + if (qspi->xfer_mode.flex_mode == false)
>> + addr |= bcm_qspi_read(qspi, BSPI,
>> + BSPI_BSPI_FLASH_UPPER_ADDR_BYTE);
>> +
>> + /* second transfer - read result into buffer */
>> + trans = list_entry(t->transfer_list.next, struct spi_transfer,
>> + transfer_list);
>> + buf = (void *)trans->rx_buf;
>> +
>> + if (!buf) {
>> + ret = -EIO;
>> + goto out;
>> + }
>> +
>> + len = trans->len;
>> + if (bcm_qspi_bspi_ver_three(qspi) == true) {
>> + /*
>> + * The address coming into this function is a raw flash
>> offset.
>> + * But for BSPI <= V3, we need to convert it to a remapped
>> BSPI
>> + * address. If it crosses a 4MB boundary, just revert back
>> to
>> + * using MSPI.
>> + */
>> + addr = (addr + 0xc00000) & 0xffffff;
>> +
>> + if (ADDR_TO_4MBYTE_SEGMENT(addr) ^
>> + ADDR_TO_4MBYTE_SEGMENT(addr + len - 1)) {
>> + ret = -1;
>> + goto out;
>> + }
>> + }
>> +
>> + /* non-aligned and very short transfers are handled by MSPI */
>> + if (unlikely(!DWORD_ALIGNED(addr) ||
>> + !DWORD_ALIGNED(buf) ||
>> + len < sizeof(u32))) {
>> + ret = -1;
>> + goto out;
>> + }
>> +
>> +retry:
>> + reinit_completion(&qspi->bspi_done);
>> + bcm_qspi_enable_bspi(qspi);
>> + len_words = (len + 3) >> 2;
>> + qspi->bspi_xfer_status = 0;
>> + qspi->bspi_xfer = trans;
>> + qspi->bspi_xfer_idx = 0;
>> + qspi->bspi_xfer_len = len;
>> + qspi->actual_length = idx + 4 + trans->len;
>> + DBG("bspi xfr addr 0x%x len 0x%x", addr, len);
>> +
>> + bcm_qspi_write(qspi, BSPI, BSPI_RAF_START_ADDR, addr);
>> + bcm_qspi_write(qspi, BSPI, BSPI_RAF_NUM_WORDS, len_words);
>> + bcm_qspi_write(qspi, BSPI, BSPI_RAF_WATERMARK, 0);
>> + bcm_qspi_clear_interrupt(qspi, QSPI_INTERRUPTS_ALL);
>> + bcm_qspi_enable_interrupt(qspi, BSPI_LR_INTERRUPTS_ALL);
>> + bcm_qspi_lr_start(qspi);
>> + /* Must flush previous writes before starting BSPI operation */
>> + mb();
>> +
>> + if (!wait_for_completion_timeout(&qspi->bspi_done, timeo)) {
>> + if (retry--)
>> + goto retry;
>> +
>> + dev_err(&qspi->pdev->dev, "timeout waiting for BSPI\n");
>> + ret = -ETIMEDOUT;
>> + }
>> +
>> +out:
>> + return ret;
>> +}
>> +
>> +static bool bcm_qspi_bspi_read(struct bcm_qspi *qspi, struct spi_device
>> *spidev,
>> + struct spi_transfer *trans)
>> +{
>> + bool ret = false;
>> + u32 nbits = SPI_NBITS_SINGLE;
>> +
>> + if (trans && trans->len && trans->tx_buf) {
>> + u8 command = ((u8 *)trans->tx_buf)[0];
>> +
>> + if (trans->rx_nbits)
>> + nbits = trans->rx_nbits;
>> +
>> + switch (command) {
>> + case SPINOR_OP_READ4_FAST:
>> + if (!bcm_qspi_is_4_byte_mode(qspi))
>> + bcm_qspi_bspi_set_mode(qspi, nbits,
>> + BSPI_ADDRLEN_4BYTES, -1);
>> + /* fall through */
>> + case SPINOR_OP_READ_FAST:
>> + if (!bcm_qspi_emulate_flash_read(qspi, spidev,
>> trans))
>> + ret = true;
>> + break;
>> + case OPCODE_QIOR_4B:
>> + case SPINOR_OP_READ_1_1_4:
>> + case SPINOR_OP_READ4_1_1_4:
>> + if (!bcm_qspi_emulate_flash_read(qspi, spidev,
>> trans))
>> + ret = true;
>> + break;
>> + default:
>> + break;
>> +
>> + }
>> + }
>> +
>> + return ret;
>> +}
>> +
>> +static void bcm_qspi_set_read_mode(struct bcm_qspi *qspi,
>> + struct spi_device *spidev,
>> + struct spi_transfer *trans)
>> +{
>> + u32 nbits = SPI_NBITS_SINGLE;
>> +
>> + if (trans && trans->len && trans->tx_buf) {
>> + u8 command = ((u8 *)trans->tx_buf)[0];
>> +
>> + if (trans->rx_nbits)
>> + nbits = trans->rx_nbits;
>> +
>> + switch (command) {
>> + case SPINOR_OP_EN4B:
>> + DBG("EN4B MODE\n");
>> + bcm_qspi_bspi_set_mode(qspi, nbits,
>> + BSPI_ADDRLEN_4BYTES, -1);
>> + break;
>> + case SPINOR_OP_EX4B:
>> + DBG("EX4B MODE\n");
>> + bcm_qspi_bspi_set_mode(qspi, nbits,
>> + BSPI_ADDRLEN_3BYTES, -1);
>> + break;
>> + case SPINOR_OP_BRWR:
>> + {
>> + u8 enable = ((u8 *)trans->tx_buf)[1];
>> +
>> + DBG(" %s 4-BYTE MODE\n",
>> + enable ? "ENABLE" : "DISABLE");
>> + bcm_qspi_bspi_set_mode(qspi, nbits,
>> + enable ? BSPI_ADDRLEN_4BYTES :
>> + BSPI_ADDRLEN_3BYTES, -1);
>> + }
>> + break;
>> + default:
>> + break;
>> + }
>> + }
>> +}
>> +
>> +static int bcm_qspi_transfer_one(struct spi_master *master,
>> + struct spi_device *spidev, struct spi_transfer *trans)
>> +{
>> + struct bcm_qspi *qspi = spi_master_get_devdata(master);
>> + int slots;
>> + unsigned long timeo = msecs_to_jiffies(100);
>> +
>> + qspi->pos.trans = trans;
>> + qspi->pos.byte = 0;
>> +
>> + while (qspi->pos.byte < trans->len) {
>> + reinit_completion(&qspi->mspi_done);
>> +
>> + slots = write_to_hw(qspi, spidev);
>> + if (!wait_for_completion_timeout(&qspi->mspi_done, timeo))
>> {
>> + dev_err(&qspi->pdev->dev, "timeout waiting for
>> MSPI\n");
>> + return -ETIMEDOUT;
>> + }
>> +
>> + if (qspi->next_udelay) {
>> + udelay(qspi->next_udelay);
>> + qspi->next_udelay = 0;
>> + }
>> +
>> + read_from_hw(qspi, slots);
>> + if (qspi->cs_change) {
>> + udelay(10);
>> + qspi->cs_change = 0;
>> + }
>> + }
>> +
>> + if (spi_transfer_is_last(master, trans))
>> + hw_stop(qspi);
>> +
>> + return 0;
>> +}
>> +
>> +static int bcm_qspi_mspi_transfer(struct spi_master *master,
>> + struct spi_message *msg)
>> +{
>> + struct spi_transfer *t;
>> + int ret = 0;
>> +
>> + list_for_each_entry(t, &msg->transfers, transfer_list) {
>> + ret = bcm_qspi_transfer_one(master, msg->spi, t);
>> + if (ret < 0)
>> + break;
>> + }
>> +
>> + return ret;
>> +}
>> +
>> +static int bcm_qspi_transfer_one_message(struct spi_master *master,
>> + struct spi_message *msg)
>> +{
>> + struct bcm_qspi *qspi = spi_master_get_devdata(master);
>> + struct spi_transfer *t, *first = NULL;
>> + int ret = 0, cs = 0;
>> + struct spi_device *spidev = msg->spi;
>> + bool try_bspi = false;
>> + unsigned int n_transfers = 0, total_len = 0;
>> +
>> + msg->status = 0;
>> + msg->actual_length = 0;
>> +
>> + list_for_each_entry(t, &msg->transfers, transfer_list) {
>> + if (!first)
>> + first = t;
>> +
>> + n_transfers++;
>> + total_len += t->len;
>> +
>> + if (n_transfers == 2 && !first->rx_buf && !t->tx_buf)
>> + try_bspi = true;
>> +
>> + if (t->cs_change ||
>> + list_is_last(&t->transfer_list, &msg->transfers)) {
>> +#ifdef CONFIG_BRCM_MSPI_ONLY
>> + try_bspi = false;
>> +#endif
>> + cs = bcm_qspi_bspi_cs(qspi, spidev->chip_select);
>> + bcm_qspi_set_read_mode(qspi, spidev, first);
>> +
>> + /* if this is a data read try to use bspi transfer
>> */
>> + if (try_bspi && cs)
>> + try_bspi = bcm_qspi_bspi_read(qspi,
>> spidev,
>> + first);
>> + else
>> + try_bspi = false;
>> +
>> + DBG("num transfers %d try_bspi %s\n", n_transfers,
>> + try_bspi ? "true" : "false");
>> +
>> + if (try_bspi == false)
>> + /* this is mspi transfer */
>> + ret = bcm_qspi_mspi_transfer(master, msg);
>> +
>> + if (ret < 0)
>> + goto exit;
>> +
>> + if (try_bspi)
>> + msg->actual_length = qspi->actual_length;
>> + else
>> + msg->actual_length += total_len;
>> +
>> + first = NULL;
>> + n_transfers = 0;
>> + total_len = 0;
>> + try_bspi = false;
>> + }
>> + }
>> +
>> +exit:
>> + msg->status = ret;
>> + spi_finalize_current_message(master);
>> + return ret;
>> +}
>> +
>> +static void bcm_qspi_cleanup(struct spi_device *spi)
>> +{
>> + struct bcm_qspi_parms *xp = spi_get_ctldata(spi);
>> +
>> + kfree(xp);
>> +}
>> +
>> +static irqreturn_t bcm_qspi_mspi_l2_isr(int irq, void *dev_id)
>> +{
>> + struct bcm_qspi_dev_id *qspi_dev_id = dev_id;
>> + struct bcm_qspi *qspi = qspi_dev_id->dev;
>> + u32 status = bcm_qspi_read(qspi, MSPI, MSPI_MSPI_STATUS);
>> +
>> + if (status & MSPI_MSPI_STATUS_SPIF) {
>> + /* clear interrupt */
>> + status &= ~MSPI_MSPI_STATUS_SPIF;
>> + bcm_qspi_write(qspi, INTR, MSPI_MSPI_STATUS, status);
>> + bcm_qspi_clear_interrupt(qspi, INTR_MSPI_DONE_MASK);
>> + complete(&qspi->mspi_done);
>> + return IRQ_HANDLED;
>> + } else
>> + return IRQ_NONE;
>> +}
>> +
>> +static irqreturn_t bcm_qspi_bspi_lr_l2_isr(int irq, void *dev_id)
>> +{
>> + struct bcm_qspi_dev_id *qspi_dev_id = dev_id;
>> + struct bcm_qspi *qspi = qspi_dev_id->dev;
>> +
>> + if (qspi->bspi_enabled && qspi->bspi_xfer) {
>> + bcm_qspi_bspi_lr_data_read(qspi);
>> + if (qspi->bspi_xfer_len == 0) {
>> + qspi->bspi_xfer = NULL;
>> + bcm_qspi_disable_interrupt(qspi,
>> +
>> BSPI_LR_INTERRUPTS_ALL);
>> + if (qspi->bspi_xfer_status)
>> + bcm_qspi_lr_clear(qspi);
>> + else
>> + bcm_qspi_flush_prefetch_buffers(qspi);
>> +
>> + complete(&qspi->bspi_done);
>> + }
>> + bcm_qspi_clear_interrupt(qspi, BSPI_LR_INTERRUPTS_ALL);
>> + return IRQ_HANDLED;
>> + }
>> +
>> + return IRQ_NONE;
>> +}
>> +
>> +static irqreturn_t bcm_qspi_bspi_lr_err_l2_isr(int irq, void *dev_id)
>> +{
>> + struct bcm_qspi_dev_id *qspi_dev_id = dev_id;
>> + struct bcm_qspi *qspi = qspi_dev_id->dev;
>> +
>> + if (qspi_dev_id->irqp->mask & BSPI_LR_INTERRUPTS_ERROR) {
>> + dev_err(&qspi->pdev->dev, "INT error\n");
>> + qspi->bspi_xfer_status = -EIO;
>> + bcm_qspi_clear_interrupt(qspi, BSPI_LR_INTERRUPTS_ERROR);
>> + complete(&qspi->bspi_done);
>> + return IRQ_HANDLED;
>> + }
>> +
>> + return IRQ_NONE;
>> +}
>> +
>> +static irqreturn_t bcm_qspi_l1_isr(int irq, void *dev_id)
>> +{
>> + struct bcm_qspi_dev_id *qspi_dev_id = dev_id;
>> + struct bcm_qspi *qspi = qspi_dev_id->dev;
>> + u32 status = bcm_qspi_read_l2int_status(qspi);
>> + irqreturn_t ret = IRQ_NONE;
>> +
>> + if (status & MSPI_INTERRUPTS_ALL)
>> + ret = bcm_qspi_mspi_l2_isr(irq, dev_id);
>> + else if (status & BSPI_LR_INTERRUPTS_DATA)
>> + ret = bcm_qspi_bspi_lr_l2_isr(irq, dev_id);
>> + else if (status & BSPI_LR_INTERRUPTS_ERROR)
>> + ret = bcm_qspi_bspi_lr_err_l2_isr(irq, dev_id);
>> +
>> + return ret;
>> +}
>> +
>> +static const struct bcm_qspi_irq qspi_irq_tab[] = {
>> + {
>> + .irq_name = "spi_lr_fullness_reached",
>> + .irq_handler = bcm_qspi_bspi_lr_l2_isr,
>> + .mask = INTR_BSPI_LR_FULLNESS_REACHED_MASK,
>> + },
>> + {
>> + .irq_name = "spi_lr_session_aborted",
>> + .irq_handler = bcm_qspi_bspi_lr_err_l2_isr,
>> + .mask = INTR_BSPI_LR_SESSION_ABORTED_MASK,
>> + },
>> + {
>> + .irq_name = "spi_lr_impatient",
>> + .irq_handler = bcm_qspi_bspi_lr_err_l2_isr,
>> + .mask = INTR_BSPI_LR_IMPATIENT_MASK,
>> + },
>> + {
>> + .irq_name = "spi_lr_session_done",
>> + .irq_handler = bcm_qspi_bspi_lr_l2_isr,
>> + .mask = INTR_BSPI_LR_SESSION_DONE_MASK,
>> + },
>> + {
>> + .irq_name = "spi_lr_overread",
>> + .irq_handler = bcm_qspi_bspi_lr_err_l2_isr,
>> + .mask = INTR_BSPI_LR_OVERREAD_MASK,
>> + },
>> + {
>> + .irq_name = "mspi_done",
>> + .irq_handler = bcm_qspi_mspi_l2_isr,
>> + .mask = INTR_MSPI_DONE_MASK,
>> + },
>> + {
>> + .irq_name = "mspi_halted",
>> + .irq_handler = bcm_qspi_mspi_l2_isr,
>> + .mask = INTR_MSPI_HALTED_MASK,
>> + },
>> + {
>> + /* single muxed L1 interrupt source */
>> + .irq_name = "spi_l1_intr",
>> + .irq_handler = bcm_qspi_l1_isr,
>> + .mask = QSPI_INTERRUPTS_ALL,
>> + },
>> +};
>> +
>> +static int bcm_qspi_simple_transaction(struct bcm_qspi *qspi,
>> + const void *tx_buf, int tx_len, void *rx_buf, int rx_len)
>> +{
>> +
>> + struct bcm_qspi_parms *xp = &qspi->last_parms;
>> + struct spi_message m;
>> + struct spi_transfer t_tx, t_rx;
>> + struct spi_device spi;
>> + int ret;
>> +
>> + memset(&spi, 0, sizeof(spi));
>> + spi.max_speed_hz = xp->speed_hz;
>> + spi.chip_select = xp->chip_select;
>> + spi.mode = xp->mode;
>> + spi.bits_per_word = xp->bits_per_word;
>> + spi.master = qspi->master;
>> +
>> + spi_message_init(&m);
>> + m.spi = &spi;
>> +
>> + memset(&t_tx, 0, sizeof(t_tx));
>> + memset(&t_rx, 0, sizeof(t_rx));
>> + t_tx.tx_buf = tx_buf;
>> + t_tx.len = tx_len;
>> + t_rx.rx_buf = rx_buf;
>> + t_rx.len = rx_len;
>> +
>> + ret = bcm_qspi_mspi_transfer(spi.master, &m);
>> +
>> + return ret;
>> +}
>> +
>> +static void bcm_qspi_hw_init(struct bcm_qspi *qspi)
>> +{
>> + u32 val = 0;
>> + struct bcm_qspi_parms default_parms;
>> +
>> + bcm_qspi_write(qspi, MSPI, MSPI_SPCR1_LSB, 0);
>> + bcm_qspi_write(qspi, MSPI, MSPI_SPCR1_MSB, 0);
>> + bcm_qspi_write(qspi, MSPI, MSPI_NEWQP, 0);
>> + bcm_qspi_write(qspi, MSPI, MSPI_ENDQP, 0);
>> + bcm_qspi_write(qspi, MSPI, MSPI_SPCR2, 0x20);
>> +
>> + default_parms.chip_select = 0;
>> + default_parms.mode = SPI_MODE_3;
>> + default_parms.bits_per_word = 8;
>> + of_property_read_u32(qspi->pdev->dev.of_node, "clock-frequency",
>> &val);
>> + if (val > 0) {
>> + default_parms.speed_hz = val;
>> + bcm_qspi_hw_set_parms(qspi, &default_parms);
>> + } else {
>> + bcm_qspi_hw_set_parms(qspi, &bcm_qspi_default_parms_cs0);
>> + }
>> +
>> + if (!qspi->base[BSPI])
>> + return;
--
Kamal Dasu
Principal Engineer | Broadcom Ltd. 200 Brickstone Sq Andover | 978-719-1405
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next prev parent reply other threads:[~2016-05-27 20:42 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-05-27 20:14 [PATCH V2, 1/4] dt: bindings: spi-bcm-qspi: NSP, NS2, BRCMSTB SoC bindings Kamal Dasu
[not found] ` <1464380097-25125-1-git-send-email-kdasu.kdev-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2016-05-27 20:14 ` [PATCH V2, 2/4] spi: bcm-qspi: Add SPI flash and MSPI driver Kamal Dasu
[not found] ` <1464380097-25125-2-git-send-email-kdasu.kdev-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2016-05-27 20:31 ` Scott Branden
[not found] ` <5748AE99.8050303-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
2016-05-27 20:42 ` Kamal Dasu [this message]
2016-05-27 20:14 ` [PATCH V2, 3/4] arm: dts: Add bcm-nsp and bcm958625k support Kamal Dasu
[not found] ` <1464380097-25125-3-git-send-email-kdasu.kdev-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2016-05-27 20:28 ` Scott Branden
[not found] ` <CAGVrzcZQMSVo4LvbqJ1jcx-f7M+psWQeHQfiRS3-L7JN+C_zuw@mail.gmail.com>
[not found] ` <CAGVrzcYfNTZWDAK8tW-HaALYXJo5zPjiWOxsB0mntCVdjnUwUg@mail.gmail.com>
[not found] ` <CAGVrzcbhoD1zDtvBXdm8DgzzXeP0MxAMtXduZMYv+BwpiwtgkQ@mail.gmail.com>
[not found] ` <CAGVrzcbhoD1zDtvBXdm8DgzzXeP0MxAMtXduZMYv+BwpiwtgkQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2016-05-27 20:47 ` Brian Norris
2016-05-27 20:47 ` Brian Norris
[not found] ` <20160527204731.GA121328-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2016-05-27 21:29 ` Florian Fainelli
2016-05-27 21:29 ` Florian Fainelli
2016-05-27 20:14 ` [PATCH V2, 4/4] arm64: dts: Add ns2 SoC support Kamal Dasu
[not found] ` <1464380097-25125-4-git-send-email-kdasu.kdev-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2016-05-27 20:26 ` Scott Branden
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