[PATCH v6 2/8] spi: rockchip-sfc: add rockchip serial flash controller
Jon Lin
jon.lin at rock-chips.com
Wed Jun 9 06:48:50 PDT 2021
On 6/9/21 10:36 AM, Chris Morgan wrote:
> On Tue, Jun 08, 2021 at 10:26:38AM +0800, Jon Lin wrote:
>> From: Chris Morgan <macromorgan at hotmail.com>
>>
>> Add the rockchip serial flash controller (SFC) driver.
>>
>> Signed-off-by: Chris Morgan <macromorgan at hotmail.com>
>> Signed-off-by: Jon Lin <jon.lin at rock-chips.com>
> I think I hit "reply" earlier when I meant to hit "reply-all". Whoops.
>
> I wanted to say that for now this driver is not working for me on the
> v3 hardware. There appears to be something wrong with alternating
> between page programs and erase. I can consistently reproduce this by
> writing a 4MB image of random data to my SPI flash chip at offset
> c00000 using dd to mtdblock0. I've dumped the contents of what is
> written to the controller and it appears at some point it goes from
> doing a page program (02) to a dual io read (bb) to a sector erase
> (20), then it repeatedly reads the status register (05) and I assume
> the register never changes. As a result it just keeps looping over
> the status register then eventually times out. I'm still debugging
> to try and figure out exactly what is going on though.
>
> I also noticed that reading does not work consistently using dd
> from the mtd0 device, however I have a proposed fix for that which
> I list below at the appropriate section.
>
Can you enable dev_dbg in rockchip_sfc_xfer_setup, then send me log.
I successfully mount and test spinor jffs2 to confirm read/write/erase
work work. I'll try more cases further.
>> ---
>>
>> Changes in v6: None
>> Changes in v5: None
>> Changes in v4: None
>> Changes in v3: None
>> Changes in v2: None
>> Changes in v1: None
>>
>> drivers/spi/Kconfig | 9 +
>> drivers/spi/Makefile | 1 +
>> drivers/spi/spi-rockchip-sfc.c | 660 +++++++++++++++++++++++++++++++++
>> 3 files changed, 670 insertions(+)
>> create mode 100644 drivers/spi/spi-rockchip-sfc.c
>>
>> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
>> index e71a4c514f7b..d89e5f3c9107 100644
>> --- a/drivers/spi/Kconfig
>> +++ b/drivers/spi/Kconfig
>> @@ -658,6 +658,15 @@ config SPI_ROCKCHIP
>> The main usecase of this controller is to use spi flash as boot
>> device.
>>
>> +config SPI_ROCKCHIP_SFC
>> + tristate "Rockchip Serial Flash Controller (SFC)"
>> + depends on ARCH_ROCKCHIP || COMPILE_TEST
>> + depends on HAS_IOMEM && HAS_DMA
>> + help
>> + This enables support for Rockchip serial flash controller. This
>> + is a specialized controller used to access SPI flash on some
>> + Rockchip SOCs.
>> +
>> config SPI_RB4XX
>> tristate "Mikrotik RB4XX SPI master"
>> depends on SPI_MASTER && ATH79
>> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
>> index 13e54c45e9df..699db95c8441 100644
>> --- a/drivers/spi/Makefile
>> +++ b/drivers/spi/Makefile
>> @@ -95,6 +95,7 @@ obj-$(CONFIG_SPI_QCOM_GENI) += spi-geni-qcom.o
>> obj-$(CONFIG_SPI_QCOM_QSPI) += spi-qcom-qspi.o
>> obj-$(CONFIG_SPI_QUP) += spi-qup.o
>> obj-$(CONFIG_SPI_ROCKCHIP) += spi-rockchip.o
>> +obj-$(CONFIG_SPI_ROCKCHIP_SFC) += spi-rockchip-sfc.o
>> obj-$(CONFIG_SPI_RB4XX) += spi-rb4xx.o
>> obj-$(CONFIG_MACH_REALTEK_RTL) += spi-realtek-rtl.o
>> obj-$(CONFIG_SPI_RPCIF) += spi-rpc-if.o
>> diff --git a/drivers/spi/spi-rockchip-sfc.c b/drivers/spi/spi-rockchip-sfc.c
>> new file mode 100644
>> index 000000000000..ec25ad278096
>> --- /dev/null
>> +++ b/drivers/spi/spi-rockchip-sfc.c
>> @@ -0,0 +1,660 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Rockchip Serial Flash Controller Driver
>> + *
>> + * Copyright (c) 2017-2021, Rockchip Inc.
>> + * Author: Shawn Lin <shawn.lin at rock-chips.com>
>> + * Chris Morgan <macroalpha82 at gmail.com>
>> + * Jon Lin <Jon.lin at rock-chips.com>
>> + */
>> +
>> +#include <linux/bitops.h>
>> +#include <linux/clk.h>
>> +#include <linux/completion.h>
>> +#include <linux/dma-mapping.h>
>> +#include <linux/iopoll.h>
>> +#include <linux/mm.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/slab.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/spi/spi-mem.h>
>> +
>> +/* System control */
>> +#define SFC_CTRL 0x0
>> +#define SFC_CTRL_PHASE_SEL_NEGETIVE BIT(1)
>> +#define SFC_CTRL_CMD_BITS_SHIFT 8
>> +#define SFC_CTRL_ADDR_BITS_SHIFT 10
>> +#define SFC_CTRL_DATA_BITS_SHIFT 12
>> +
>> +/* Interrupt mask */
>> +#define SFC_IMR 0x4
>> +#define SFC_IMR_RX_FULL BIT(0)
>> +#define SFC_IMR_RX_UFLOW BIT(1)
>> +#define SFC_IMR_TX_OFLOW BIT(2)
>> +#define SFC_IMR_TX_EMPTY BIT(3)
>> +#define SFC_IMR_TRAN_FINISH BIT(4)
>> +#define SFC_IMR_BUS_ERR BIT(5)
>> +#define SFC_IMR_NSPI_ERR BIT(6)
>> +#define SFC_IMR_DMA BIT(7)
>> +
>> +/* Interrupt clear */
>> +#define SFC_ICLR 0x8
>> +#define SFC_ICLR_RX_FULL BIT(0)
>> +#define SFC_ICLR_RX_UFLOW BIT(1)
>> +#define SFC_ICLR_TX_OFLOW BIT(2)
>> +#define SFC_ICLR_TX_EMPTY BIT(3)
>> +#define SFC_ICLR_TRAN_FINISH BIT(4)
>> +#define SFC_ICLR_BUS_ERR BIT(5)
>> +#define SFC_ICLR_NSPI_ERR BIT(6)
>> +#define SFC_ICLR_DMA BIT(7)
>> +
>> +/* FIFO threshold level */
>> +#define SFC_FTLR 0xc
>> +#define SFC_FTLR_TX_SHIFT 0
>> +#define SFC_FTLR_TX_MASK 0x1f
>> +#define SFC_FTLR_RX_SHIFT 8
>> +#define SFC_FTLR_RX_MASK 0x1f
>> +
>> +/* Reset FSM and FIFO */
>> +#define SFC_RCVR 0x10
>> +#define SFC_RCVR_RESET BIT(0)
>> +
>> +/* Enhanced mode */
>> +#define SFC_AX 0x14
>> +
>> +/* Address Bit number */
>> +#define SFC_ABIT 0x18
>> +
>> +/* Interrupt status */
>> +#define SFC_ISR 0x1c
>> +#define SFC_ISR_RX_FULL_SHIFT BIT(0)
>> +#define SFC_ISR_RX_UFLOW_SHIFT BIT(1)
>> +#define SFC_ISR_TX_OFLOW_SHIFT BIT(2)
>> +#define SFC_ISR_TX_EMPTY_SHIFT BIT(3)
>> +#define SFC_ISR_TX_FINISH_SHIFT BIT(4)
>> +#define SFC_ISR_BUS_ERR_SHIFT BIT(5)
>> +#define SFC_ISR_NSPI_ERR_SHIFT BIT(6)
>> +#define SFC_ISR_DMA_SHIFT BIT(7)
>> +
>> +/* FIFO status */
>> +#define SFC_FSR 0x20
>> +#define SFC_FSR_TX_IS_FULL BIT(0)
>> +#define SFC_FSR_TX_IS_EMPTY BIT(1)
>> +#define SFC_FSR_RX_IS_EMPTY BIT(2)
>> +#define SFC_FSR_RX_IS_FULL BIT(3)
>> +#define SFC_FSR_TXLV_MASK GENMASK(12, 8)
>> +#define SFC_FSR_TXLV_SHIFT 8
>> +#define SFC_FSR_RXLV_MASK GENMASK(20, 16)
>> +#define SFC_FSR_RXLV_SHIFT 16
>> +
>> +/* FSM status */
>> +#define SFC_SR 0x24
>> +#define SFC_SR_IS_IDLE 0x0
>> +#define SFC_SR_IS_BUSY 0x1
>> +
>> +/* Raw interrupt status */
>> +#define SFC_RISR 0x28
>> +#define SFC_RISR_RX_FULL BIT(0)
>> +#define SFC_RISR_RX_UNDERFLOW BIT(1)
>> +#define SFC_RISR_TX_OVERFLOW BIT(2)
>> +#define SFC_RISR_TX_EMPTY BIT(3)
>> +#define SFC_RISR_TRAN_FINISH BIT(4)
>> +#define SFC_RISR_BUS_ERR BIT(5)
>> +#define SFC_RISR_NSPI_ERR BIT(6)
>> +#define SFC_RISR_DMA BIT(7)
>> +
>> +/* Version */
>> +#define SFC_VER 0x2C
>> +#define SFC_VER_3 0x3
>> +#define SFC_VER_4 0x4
>> +#define SFC_VER_5 0x5
>> +
>> +/* Master trigger */
>> +#define SFC_DMA_TRIGGER 0x80
>> +
>> +/* Src or Dst addr for master */
>> +#define SFC_DMA_ADDR 0x84
>> +
>> +/* Length control register extension 32GB */
>> +#define SFC_LEN_CTRL 0x88
>> +#define SFC_LEN_CTRL_TRB_SEL 1
>> +#define SFC_LEN_EXT 0x8C
>> +
>> +/* Command */
>> +#define SFC_CMD 0x100
>> +#define SFC_CMD_IDX_SHIFT 0
>> +#define SFC_CMD_DUMMY_SHIFT 8
>> +#define SFC_CMD_DIR_SHIFT 12
>> +#define SFC_CMD_DIR_RD 0
>> +#define SFC_CMD_DIR_WR 1
>> +#define SFC_CMD_ADDR_SHIFT 14
>> +#define SFC_CMD_ADDR_0BITS 0
>> +#define SFC_CMD_ADDR_24BITS 1
>> +#define SFC_CMD_ADDR_32BITS 2
>> +#define SFC_CMD_ADDR_XBITS 3
>> +#define SFC_CMD_TRAN_BYTES_SHIFT 16
>> +#define SFC_CMD_CS_SHIFT 30
>> +
>> +/* Address */
>> +#define SFC_ADDR 0x104
>> +
>> +/* Data */
>> +#define SFC_DATA 0x108
>> +
>> +/* The controller and documentation reports that it supports up to 4 CS
>> + * devices (0-3), however I have only been able to test a single CS (CS 0)
>> + * due to the configuration of my device.
>> + */
>> +#define SFC_MAX_CHIPSELECT_NUM 4
>> +
>> +/* The SFC can transfer max 16KB - 1 at one time
>> + * we set it to 15.5KB here for alignment.
>> + */
>> +#define SFC_MAX_IOSIZE_VER3 (512 * 31)
>> +
>> +#define SFC_MAX_IOSIZE_VER4 (0xFFFFFFFF)
>> +
>> +/* DMA is only enabled for large data transmission */
>> +#define SFC_DMA_TRANS_THRETHOLD (0x40)
>> +
>> +/* Maximum clock values from datasheet suggest keeping clock value under
>> + * 150MHz. No minimum or average value is suggested, but the U-boot BSP driver
>> + * has a minimum of 10MHz and a default of 80MHz which seems reasonable.
>> + */
>> +#define SFC_MIN_SPEED_HZ (10 * 1000 * 1000)
>> +#define SFC_DEFAULT_SPEED_HZ (80 * 1000 * 1000)
>> +#define SFC_MAX_SPEED_HZ (150 * 1000 * 1000)
>> +
>> +struct rockchip_sfc {
>> + struct device *dev;
>> + void __iomem *regbase;
>> + struct clk *hclk;
>> + struct clk *clk;
>> + u32 frequency;
>> + /* virtual mapped addr for dma_buffer */
>> + void *buffer;
>> + dma_addr_t dma_buffer;
>> + struct completion cp;
>> + bool use_dma;
>> + u32 max_iosize;
>> +};
>> +
>> +static int rockchip_sfc_reset(struct rockchip_sfc *sfc)
>> +{
>> + int err;
>> + u32 status;
>> +
>> + writel_relaxed(SFC_RCVR_RESET, sfc->regbase + SFC_RCVR);
>> +
>> + err = readl_poll_timeout(sfc->regbase + SFC_RCVR, status,
>> + !(status & SFC_RCVR_RESET), 20,
>> + jiffies_to_usecs(HZ));
>> + if (err)
>> + dev_err(sfc->dev, "SFC reset never finished\n");
>> +
>> + /* Still need to clear the masked interrupt from RISR */
>> + writel_relaxed(0xFFFFFFFF, sfc->regbase + SFC_ICLR);
>> +
>> + dev_dbg(sfc->dev, "reset\n");
>> +
>> + return err;
>> +}
>> +
>> +static u16 rockchip_sfc_get_version(struct rockchip_sfc *sfc)
>> +{
>> + return (u16)(readl(sfc->regbase + SFC_VER) & 0xffff);
>> +}
>> +
>> +static u32 rockchip_sfc_get_max_iosize(struct rockchip_sfc *sfc)
>> +{
>> + if (rockchip_sfc_get_version(sfc) >= SFC_VER_4)
>> + return SFC_MAX_IOSIZE_VER4;
>> + else
>> + return SFC_MAX_IOSIZE_VER3;
>> +}
>> +
>> +static int rockchip_sfc_init(struct rockchip_sfc *sfc)
>> +{
>> + writel(0, sfc->regbase + SFC_CTRL);
>> + if (rockchip_sfc_get_version(sfc) >= SFC_VER_4)
>> + writel(SFC_LEN_CTRL_TRB_SEL, sfc->regbase + SFC_LEN_CTRL);
>> +
>> + return 0;
>> +}
>> +
>> +static inline int rockchip_sfc_get_fifo_level(struct rockchip_sfc *sfc, int wr)
>> +{
>> + u32 fsr = readl_relaxed(sfc->regbase + SFC_FSR);
>> + int level;
>> +
>> + if (wr)
>> + level = (fsr & SFC_FSR_TXLV_MASK) >> SFC_FSR_TXLV_SHIFT;
>> + else
>> + level = (fsr & SFC_FSR_RXLV_MASK) >> SFC_FSR_RXLV_SHIFT;
>> +
>> + return level;
>> +}
>> +
>> +static int rockchip_sfc_wait_fifo_ready(struct rockchip_sfc *sfc, int wr, u32 timeout)
>> +{
>> + unsigned long deadline = jiffies + timeout;
>> + int level;
>> +
>> + while (!(level = rockchip_sfc_get_fifo_level(sfc, wr))) {
>> + if (time_after_eq(jiffies, deadline)) {
>> + dev_warn(sfc->dev, "%s fifo timeout\n", wr ? "write" : "read");
>> + return -ETIMEDOUT;
>> + }
>> + udelay(1);
>> + }
>> +
>> + return level;
>> +}
>> +
>> +static int rockchip_sfc_xfer_setup(struct rockchip_sfc *sfc,
>> + struct spi_mem *mem,
>> + const struct spi_mem_op *op,
>> + u32 len)
>> +{
>> + u32 ctrl = 0, cmd = 0;
>> +
>> + /* set CMD */
>> + cmd = op->cmd.opcode;
>> + ctrl |= ((op->cmd.buswidth >> 1) << SFC_CTRL_CMD_BITS_SHIFT);
>> +
>> + /* set ADDR */
>> + if (op->addr.nbytes) {
>> + if (op->addr.nbytes == 4) {
>> + cmd |= SFC_CMD_ADDR_32BITS << SFC_CMD_ADDR_SHIFT;
>> + } else if (op->addr.nbytes == 3) {
>> + cmd |= SFC_CMD_ADDR_24BITS << SFC_CMD_ADDR_SHIFT;
>> + } else {
>> + cmd |= SFC_CMD_ADDR_XBITS << SFC_CMD_ADDR_SHIFT;
>> + writel_relaxed(op->addr.nbytes * 8 - 1, sfc->regbase + SFC_ABIT);
>> + }
>> +
>> + ctrl |= ((op->addr.buswidth >> 1) << SFC_CTRL_ADDR_BITS_SHIFT);
>> + }
>> +
>> + /* set DUMMY */
>> + if (op->dummy.nbytes) {
>> + if (op->dummy.buswidth == 4)
>> + cmd |= op->dummy.nbytes * 2 << SFC_CMD_DUMMY_SHIFT;
>> + else if (op->dummy.buswidth == 2)
>> + cmd |= op->dummy.nbytes * 4 << SFC_CMD_DUMMY_SHIFT;
>> + else
>> + cmd |= op->dummy.nbytes * 8 << SFC_CMD_DUMMY_SHIFT;
>> + }
>> +
> I have no experience optimizing code or anything, but would it help
> here to read the output of rockchip_sfc_get_version() to a variable
> in the driver data, and then check that each time we hit this?
> I don't know if there is any real-world difference in reading a
> variable versus reading a register, so I'm just asking. It's not like
> the sfc_version will change once the device is probed. :-)
done.
>> + /* set DATA */
>> + if (rockchip_sfc_get_version(sfc) >= SFC_VER_4) /* Clear it if no data to transfer */
>> + writel(len, sfc->regbase + SFC_LEN_EXT);
>> + else
>> + cmd |= len << SFC_CMD_TRAN_BYTES_SHIFT;
>> + if (len) {
>> + if (op->data.dir == SPI_MEM_DATA_OUT)
>> + cmd |= SFC_CMD_DIR_WR << SFC_CMD_DIR_SHIFT;
>> +
>> + ctrl |= ((op->data.buswidth >> 1) << SFC_CTRL_DATA_BITS_SHIFT);
>> + }
>> + if (!len && op->addr.nbytes)
>> + cmd |= SFC_CMD_DIR_WR << SFC_CMD_DIR_SHIFT;
>> +
>> + /* set the Controller */
>> + ctrl |= SFC_CTRL_PHASE_SEL_NEGETIVE;
>> + cmd |= mem->spi->chip_select << SFC_CMD_CS_SHIFT;
>> +
>> + dev_dbg(sfc->dev, "addr.nbytes=%x(x%d) dummy.nbytes=%x(x%d)\n",
>> + op->addr.nbytes, op->addr.buswidth,
>> + op->dummy.nbytes, op->dummy.buswidth);
>> + dev_dbg(sfc->dev, "ctrl=%x cmd=%x addr=%llx len=%x\n",
>> + ctrl, cmd, op->addr.val, len);
>> +
>> + writel(ctrl, sfc->regbase + SFC_CTRL);
>> + writel(cmd, sfc->regbase + SFC_CMD);
>> + if (op->addr.nbytes)
>> + writel(op->addr.val, sfc->regbase + SFC_ADDR);
>> +
>> + return 0;
>> +}
>> +
>> +static int rockchip_sfc_write_fifo(struct rockchip_sfc *sfc, const u8 *buf, int len)
>> +{
>> + u8 bytes = len & 0x3;
>> + u32 dwords;
>> + int tx_level;
>> + u32 write_words;
>> + u32 tmp = 0;
>> +
>> + dwords = len >> 2;
>> + while (dwords) {
>> + tx_level = rockchip_sfc_wait_fifo_ready(sfc, SFC_CMD_DIR_WR, HZ);
>> + if (tx_level < 0)
>> + return tx_level;
>> + write_words = min_t(u32, tx_level, dwords);
>> + iowrite32_rep(sfc->regbase + SFC_DATA, buf, write_words);
>> + buf += write_words << 2;
>> + dwords -= write_words;
>> + }
>> +
>> + /* write the rest non word aligned bytes */
>> + if (bytes) {
>> + tx_level = rockchip_sfc_wait_fifo_ready(sfc, SFC_CMD_DIR_WR, HZ);
>> + if (tx_level < 0)
>> + return tx_level;
>> + memcpy(&tmp, buf, bytes);
>> + writel(tmp, sfc->regbase + SFC_DATA);
>> + }
>> +
>> + return len;
>> +}
>> +
>> +static int rockchip_sfc_read_fifo(struct rockchip_sfc *sfc, u8 *buf, int len)
>> +{
>> + u8 bytes = len & 0x3;
>> + u32 dwords;
>> + u8 read_words;
>> + int rx_level;
>> + int tmp;
>> +
>> + /* word aligned access only */
>> + dwords = len >> 2;
>> + while (dwords) {
>> + rx_level = rockchip_sfc_wait_fifo_ready(sfc, SFC_CMD_DIR_RD, HZ);
>> + if (rx_level < 0)
>> + return rx_level;
>> + read_words = min_t(u32, rx_level, dwords);
>> + ioread32_rep(sfc->regbase + SFC_DATA, buf, read_words);
>> + buf += read_words << 2;
>> + dwords -= read_words;
>> + }
>> +
>> + /* read the rest non word aligned bytes */
>> + if (bytes) {
>> + rx_level = rockchip_sfc_wait_fifo_ready(sfc, SFC_CMD_DIR_RD, HZ);
>> + if (rx_level < 0)
>> + return rx_level;
>> + tmp = readl_relaxed(sfc->regbase + SFC_DATA);
>> + memcpy(buf, &tmp, bytes);
>> + }
>> +
>> + return len;
>> +}
>> +
>> +static int rockchip_sfc_fifo_transfer_dma(struct rockchip_sfc *sfc, dma_addr_t dma_buf, size_t len)
>> +{
>> + u32 reg;
>> + int err = 0;
>> +
>> + init_completion(&sfc->cp);
>> +
>> + writel(0xFFFFFFFF, sfc->regbase + SFC_ICLR);
>> +
>> + /* Enable transfer complete interrupt */
>> + reg = readl(sfc->regbase + SFC_IMR);
>> + reg &= ~SFC_IMR_DMA;
>> + writel(reg, sfc->regbase + SFC_IMR);
>> + writel((u32)dma_buf, sfc->regbase + SFC_DMA_ADDR);
>> + writel(0x1, sfc->regbase + SFC_DMA_TRIGGER);
>> +
>> + /* Wait for the interrupt. */
>> + if (!wait_for_completion_timeout(&sfc->cp, msecs_to_jiffies(2000))) {
>> + dev_err(sfc->dev, "DMA wait for transfer finish timeout\n");
>> + err = -ETIMEDOUT;
>> + }
>> +
>> + writel(0xFFFFFFFF, sfc->regbase + SFC_ICLR);
>> + /* Disable transfer finish interrupt */
>> + reg = readl(sfc->regbase + SFC_IMR);
>> + reg |= SFC_IMR_DMA;
>> + writel(reg, sfc->regbase + SFC_IMR);
>> +
>> + return len;
>> +}
>> +
>> +static int rockchip_sfc_xfer_data_poll(struct rockchip_sfc *sfc,
>> + const struct spi_mem_op *op, u32 len)
>> +{
>> + dev_dbg(sfc->dev, "xfer_poll len=%x\n", len);
>> +
>> + if (op->data.dir == SPI_MEM_DATA_OUT)
>> + return rockchip_sfc_write_fifo(sfc, op->data.buf.out, len);
>> + else
>> + return rockchip_sfc_read_fifo(sfc, op->data.buf.in, len);
>> +}
>> +
>> +static int rockchip_sfc_xfer_data_dma(struct rockchip_sfc *sfc,
>> + const struct spi_mem_op *op, u32 len)
>> +{
>> + int ret;
>> +
>> + dev_dbg(sfc->dev, "xfer_dma len=%x\n", len);
>> +
>> + if (op->data.dir == SPI_MEM_DATA_OUT) {
>> + memcpy_toio(sfc->buffer, op->data.buf.out, len);
>> + ret = rockchip_sfc_fifo_transfer_dma(sfc, sfc->dma_buffer, len);
>> + } else {
>> + ret = rockchip_sfc_fifo_transfer_dma(sfc, sfc->dma_buffer, len);
>> + memcpy_fromio(op->data.buf.in, sfc->buffer, len);
>> + }
>> +
>> + return ret;
>> +}
>> +
>> +static int rockchip_sfc_xfer_done(struct rockchip_sfc *sfc, u32 timeout_us)
>> +{
>> + int ret = 0;
>> + u32 status;
>> +
>> + ret = readl_poll_timeout(sfc->regbase + SFC_SR, status,
>> + !(status & SFC_SR_IS_BUSY),
>> + 20, timeout_us);
>> + if (ret) {
>> + dev_err(sfc->dev, "wait sfc idle timeout\n");
>> + rockchip_sfc_reset(sfc);
>> +
>> + ret = -EIO;
>> + }
>> +
>> + return ret;
>> +}
>> +
>> +static int rockchip_sfc_exec_mem_op(struct spi_mem *mem, const struct spi_mem_op *op)
>> +{
>> + struct rockchip_sfc *sfc = spi_master_get_devdata(mem->spi->master);
>> + u32 len = min_t(u32, op->data.nbytes, sfc->max_iosize);
> Is it necessary to use the minimum of these 2 values if we use an
> adjust_op_size which I propose below?
it necessary if use adjust_op_size, done.
>> + int ret;
>> +
> Again I'm asking this as someone with no experience optimizing code
> or with compilers, but would it help to add an unlikely() here? It's
> all but guaranteed the first time this code path is called the clock
> will need to be set, but each subsequent call should not really have
> to care since the clock likely won't be changing (as long as we're on
> the same CS). We can also then set the sfc->frequency to what the
> max_speed_hz was after successfully setting the rate so we can hit the
> faster path after the first run (it looks like it's checking the
> uninitalized value but never updating it after it's changed, so it's
> always doing the clk_set_rate()).
>
> Also, should we clamp the clock speed between the min and max values?
done.
>> + if (mem->spi->max_speed_hz != sfc->frequency) {
>> + if (clk_set_rate(sfc->clk, mem->spi->max_speed_hz))
>> + return ret;
>> + dev_dbg(sfc->dev, "set_freq=%dHz real_freq=%ldHz\n",
>> + sfc->frequency, clk_get_rate(sfc->clk));
>> + }
>> +
>> + rockchip_sfc_xfer_setup(sfc, mem, op, len);
>> + if (len) {
>> + if (likely(sfc->use_dma) && !(len & 0x3) && len >= SFC_DMA_TRANS_THRETHOLD)
>> + ret = rockchip_sfc_xfer_data_dma(sfc, op, len);
>> + else
>> + ret = rockchip_sfc_xfer_data_poll(sfc, op, len);
>> +
>> + if (ret != len) {
>> + dev_err(sfc->dev, "xfer data failed ret %d dir %d\n", ret, op->data.dir);
>> +
>> + return -EIO;
>> + }
>> + }
>> +
>> + return rockchip_sfc_xfer_done(sfc, 100000);
>> +}
>> +
> I'll be honest with you, I had no idea if I needed this function or
> not (the rockchip_sfc_get_name() function). I'm pretty sure it's not
> needed though, so I assume it can be safely removed.
>
>> +static const char *rockchip_sfc_get_name(struct spi_mem *mem)
>> +{
>> + return devm_kasprintf(&mem->spi->dev, GFP_KERNEL, "%s.%d",
>> + dev_name(&mem->spi->dev), mem->spi->chip_select);
>> +}
>> +
> I had an issue with doing dd as mentioned above reading against mtd0,
> and was able to fix it by adding a mem_op of adjust_op_size like this.
> Not sure if it works for the v4/v5 hardware though.
>
> static int rockchip_sfc_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
> {
> struct rockchip_sfc *sfc = spi_master_get_devdata(mem->spi->master);
>
> op->data.nbytes = min(op->data.nbytes, sfc->max_iosize);
> return 0;
> }
good idea.
>> +static const struct spi_controller_mem_ops rockchip_sfc_mem_ops = {
>> + .exec_op = rockchip_sfc_exec_mem_op,
>> + .get_name = rockchip_sfc_get_name,
>> +};
>> +
>> +static irqreturn_t rockchip_sfc_irq_handler(int irq, void *dev_id)
>> +{
>> + struct rockchip_sfc *sfc = dev_id;
>> + u32 reg;
>> +
>> + reg = readl(sfc->regbase + SFC_RISR);
>> +
>> + /* Clear interrupt */
>> + writel_relaxed(reg, sfc->regbase + SFC_ICLR);
>> +
>> + if (reg & SFC_RISR_DMA)
>> + complete(&sfc->cp);
>> +
> >From a previous comment, we should only clear the interrupt if we
> handle the specific one in question.
>
Compare with drivers/spi/spi-cadence-quadspi.c, I think the former code
work well. Can explain more for the reason.
>> + return IRQ_HANDLED;
>> +}
>> +
>> +static int rockchip_sfc_probe(struct platform_device *pdev)
>> +{
>> + struct device *dev = &pdev->dev;
>> + struct spi_master *master;
>> + struct resource *res;
>> + struct rockchip_sfc *sfc;
>> + int ret;
>> +
>> + master = devm_spi_alloc_master(&pdev->dev, sizeof(*sfc));
>> + if (!master)
>> + return -ENOMEM;
>> +
>> + master->mem_ops = &rockchip_sfc_mem_ops;
>> + master->dev.of_node = pdev->dev.of_node;
>> + master->mode_bits = SPI_TX_QUAD | SPI_TX_DUAL | SPI_RX_QUAD | SPI_RX_DUAL;
>> + master->min_speed_hz = SFC_MIN_SPEED_HZ;
>> + master->max_speed_hz = SFC_MAX_SPEED_HZ;
>> + master->num_chipselect = SFC_MAX_CHIPSELECT_NUM;
>> +
>> + sfc = spi_master_get_devdata(master);
>> + sfc->dev = dev;
>> +
>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> + sfc->regbase = devm_ioremap_resource(dev, res);
>> + if (IS_ERR(sfc->regbase))
>> + return PTR_ERR(sfc->regbase);
>> +
>> + sfc->clk = devm_clk_get(&pdev->dev, "clk_sfc");
>> + if (IS_ERR(sfc->clk)) {
>> + dev_err(&pdev->dev, "Failed to get sfc interface clk\n");
>> + return PTR_ERR(sfc->clk);
>> + }
>> +
>> + sfc->hclk = devm_clk_get(&pdev->dev, "hclk_sfc");
>> + if (IS_ERR(sfc->hclk)) {
>> + dev_err(&pdev->dev, "Failed to get sfc ahb clk\n");
>> + return PTR_ERR(sfc->hclk);
>> + }
>> +
>> + sfc->use_dma = !of_property_read_bool(sfc->dev->of_node,
>> + "rockchip,sfc-no-dma");
>> +
>> + if (sfc->use_dma) {
>> + ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
>> + if (ret) {
>> + dev_warn(dev, "Unable to set dma mask\n");
>> + return ret;
>> + }
>> +
>> + sfc->buffer = dmam_alloc_coherent(dev, SFC_MAX_IOSIZE_VER3,
>> + &sfc->dma_buffer,
>> + GFP_KERNEL);
>> + if (!sfc->buffer)
>> + return -ENOMEM;
>> + }
>> +
>> + ret = clk_prepare_enable(sfc->hclk);
>> + if (ret) {
>> + dev_err(&pdev->dev, "Failed to enable ahb clk\n");
>> + goto err_hclk;
>> + }
>> +
>> + ret = clk_prepare_enable(sfc->clk);
>> + if (ret) {
>> + dev_err(&pdev->dev, "Failed to enable interface clk\n");
>> + goto err_clk;
>> + }
>> +
>> + /* Find the irq */
>> + ret = platform_get_irq(pdev, 0);
>> + if (ret < 0) {
>> + dev_err(dev, "Failed to get the irq\n");
>> + goto err_irq;
>> + }
>> +
>> + ret = devm_request_irq(dev, ret, rockchip_sfc_irq_handler,
>> + 0, pdev->name, sfc);
>> + if (ret) {
>> + dev_err(dev, "Failed to request irq\n");
>> +
>> + return ret;
>> + }
>> +
>> + ret = rockchip_sfc_init(sfc);
>> + if (ret)
>> + goto err_irq;
>> +
>> + sfc->max_iosize = rockchip_sfc_get_max_iosize(sfc);
>> +
>> + ret = spi_register_master(master);
>> + if (ret)
>> + goto err_irq;
>> +
>> + return 0;
>> +
>> +err_irq:
>> + clk_disable_unprepare(sfc->clk);
>> +err_clk:
>> + clk_disable_unprepare(sfc->hclk);
>> +err_hclk:
>> + return ret;
>> +}
>> +
>> +static int rockchip_sfc_remove(struct platform_device *pdev)
>> +{
>> + struct spi_master *master = platform_get_drvdata(pdev);
>> + struct rockchip_sfc *sfc = platform_get_drvdata(pdev);
>> +
>> + spi_unregister_master(master);
>> +
>> + clk_disable_unprepare(sfc->clk);
>> + clk_disable_unprepare(sfc->hclk);
>> +
>> + return 0;
>> +}
>> +
>> +static const struct of_device_id rockchip_sfc_dt_ids[] = {
>> + { .compatible = "rockchip,px30-sfc"},
>> + { .compatible = "rockchip,rk3036-sfc"},
>> + { .compatible = "rockchip,rk3308-sfc"},
>> + { .compatible = "rockchip,rv1126-sfc"},
>> + { /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, rockchip_sfc_dt_ids);
>> +
>> +static struct platform_driver rockchip_sfc_driver = {
>> + .driver = {
>> + .name = "rockchip-sfc",
>> + .of_match_table = rockchip_sfc_dt_ids,
>> + },
>> + .probe = rockchip_sfc_probe,
>> + .remove = rockchip_sfc_remove,
>> +};
>> +module_platform_driver(rockchip_sfc_driver);
>> +
>> +MODULE_LICENSE("GPL v2");
>> +MODULE_DESCRIPTION("Rockchip Serial Flash Controller Driver");
>> +MODULE_AUTHOR("Shawn Lin <shawn.lin at rock-chips.com>");
>> +MODULE_AUTHOR("Chris Morgan <macroalpha82 at gmail.com>");
> I know folks will hate on me for this (and for good reason given it
> messes up IDs and stuff), but I prefer macromorgan at hotmail.com if my
> email is in here, as that's the one I've been using for decades...
ok.
>> +MODULE_AUTHOR("Jon Lin <Jon.lin at rock-chips.com>");
>> --
>> 2.17.1
>>
>>
>>
>
>
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