spi: rockchip-sfc: add rockchip serial flash controller
authorChris Morgan <macromorgan@hotmail.com>
Thu, 12 Aug 2021 13:45:42 +0000 (21:45 +0800)
committerMark Brown <broonie@kernel.org>
Tue, 17 Aug 2021 12:36:04 +0000 (13:36 +0100)
Add the rockchip serial flash controller (SFC) driver.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Jon Lin <jon.lin@rock-chips.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Tested-by: Chris Morgan <macromorgan@hotmail.com>
Link: https://lore.kernel.org/r/20210812134546.31340-3-jon.lin@rock-chips.com
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/spi/Kconfig
drivers/spi/Makefile
drivers/spi/spi-rockchip-sfc.c [new file with mode: 0644]

index e71a4c5..83e352b 100644 (file)
@@ -658,6 +658,18 @@ 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.
+
+         ROCKCHIP SFC supports DMA and PIO modes. When DMA is not available,
+         the driver automatically falls back to PIO mode.
+
 config SPI_RB4XX
        tristate "Mikrotik RB4XX SPI master"
        depends on SPI_MASTER && ATH79
index 13e54c4..699db95 100644 (file)
@@ -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 (file)
index 0000000..7c4d47f
--- /dev/null
@@ -0,0 +1,694 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Rockchip Serial Flash Controller Driver
+ *
+ * Copyright (c) 2017-2021, Rockchip Inc.
+ * Author: Shawn Lin <shawn.lin@rock-chips.com>
+ *        Chris Morgan <macroalpha82@gmail.com>
+ *        Jon Lin <Jon.lin@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
+
+/* Delay line controller resiter */
+#define SFC_DLL_CTRL0                  0x3C
+#define SFC_DLL_CTRL0_SCLK_SMP_DLL     BIT(15)
+#define SFC_DLL_CTRL0_DLL_MAX_VER4     0xFFU
+#define SFC_DLL_CTRL0_DLL_MAX_VER5     0x1FFU
+
+/* Master trigger */
+#define SFC_DMA_TRIGGER                        0x80
+#define SFC_DMA_TRIGGER_START          1
+
+/* 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)
+
+/* 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.
+ */
+#define SFC_MAX_SPEED          (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;
+       u16 version;
+};
+
+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)
+{
+       return SFC_MAX_IOSIZE_VER3;
+}
+
+static void rockchip_sfc_irq_unmask(struct rockchip_sfc *sfc, u32 mask)
+{
+       u32 reg;
+
+       /* Enable transfer complete interrupt */
+       reg = readl(sfc->regbase + SFC_IMR);
+       reg &= ~mask;
+       writel(reg, sfc->regbase + SFC_IMR);
+}
+
+static void rockchip_sfc_irq_mask(struct rockchip_sfc *sfc, u32 mask)
+{
+       u32 reg;
+
+       /* Disable transfer finish interrupt */
+       reg = readl(sfc->regbase + SFC_IMR);
+       reg |= mask;
+       writel(reg, sfc->regbase + SFC_IMR);
+}
+
+static int rockchip_sfc_init(struct rockchip_sfc *sfc)
+{
+       writel(0, sfc->regbase + SFC_CTRL);
+       writel(0xFFFFFFFF, sfc->regbase + SFC_ICLR);
+       rockchip_sfc_irq_mask(sfc, 0xFFFFFFFF);
+       if (rockchip_sfc_get_version(sfc) >= SFC_VER_4)
+               writel(SFC_LEN_CTRL_TRB_SEL, sfc->regbase + SFC_LEN_CTRL);
+
+       return 0;
+}
+
+static int rockchip_sfc_wait_txfifo_ready(struct rockchip_sfc *sfc, u32 timeout_us)
+{
+       int ret = 0;
+       u32 status;
+
+       ret = readl_poll_timeout(sfc->regbase + SFC_FSR, status,
+                                status & SFC_FSR_TXLV_MASK, 0,
+                                timeout_us);
+       if (ret) {
+               dev_dbg(sfc->dev, "sfc wait tx fifo timeout\n");
+
+               ret = -ETIMEDOUT;
+       }
+
+       return (status & SFC_FSR_TXLV_MASK) >> SFC_FSR_TXLV_SHIFT;
+}
+
+static int rockchip_sfc_wait_rxfifo_ready(struct rockchip_sfc *sfc, u32 timeout_us)
+{
+       int ret = 0;
+       u32 status;
+
+       ret = readl_poll_timeout(sfc->regbase + SFC_FSR, status,
+                                status & SFC_FSR_RXLV_MASK, 0,
+                                timeout_us);
+       if (ret) {
+               dev_dbg(sfc->dev, "sfc wait rx fifo timeout\n");
+
+               ret = -ETIMEDOUT;
+       }
+
+       return (status & SFC_FSR_RXLV_MASK) >> SFC_FSR_RXLV_SHIFT;
+}
+
+static void rockchip_sfc_adjust_op_work(struct spi_mem_op *op)
+{
+       if (unlikely(op->dummy.nbytes && !op->addr.nbytes)) {
+               /*
+                * SFC not support output DUMMY cycles right after CMD cycles, so
+                * treat it as ADDR cycles.
+                */
+               op->addr.nbytes = op->dummy.nbytes;
+               op->addr.buswidth = op->dummy.buswidth;
+               op->addr.val = 0xFFFFFFFFF;
+
+               op->dummy.nbytes = 0;
+       }
+}
+
+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(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;
+       }
+
+       /* set DATA */
+       if (sfc->version >= 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, "sfc 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, "sfc 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_txfifo_ready(sfc, 1000);
+               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_txfifo_ready(sfc, 1000);
+               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_rxfifo_ready(sfc, 1000);
+               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_rxfifo_ready(sfc, 1000);
+               if (rx_level < 0)
+                       return rx_level;
+               tmp = readl(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)
+{
+       writel(0xFFFFFFFF, sfc->regbase + SFC_ICLR);
+       writel((u32)dma_buf, sfc->regbase + SFC_DMA_ADDR);
+       writel(SFC_DMA_TRIGGER_START, sfc->regbase + SFC_DMA_TRIGGER);
+
+       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, "sfc 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, "sfc 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);
+       if (!wait_for_completion_timeout(&sfc->cp, msecs_to_jiffies(2000))) {
+               dev_err(sfc->dev, "DMA wait for transfer finish timeout\n");
+               ret = -ETIMEDOUT;
+       }
+       rockchip_sfc_irq_mask(sfc, SFC_IMR_DMA);
+       if (op->data.dir == SPI_MEM_DATA_IN)
+               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 = op->data.nbytes;
+       int ret;
+
+       if (unlikely(mem->spi->max_speed_hz != sfc->frequency)) {
+               ret = clk_set_rate(sfc->clk, mem->spi->max_speed_hz);
+               if (ret)
+                       return ret;
+               sfc->frequency = mem->spi->max_speed_hz;
+               dev_dbg(sfc->dev, "set_freq=%dHz real_freq=%ldHz\n",
+                       sfc->frequency, clk_get_rate(sfc->clk));
+       }
+
+       rockchip_sfc_adjust_op_work((struct spi_mem_op *)op);
+       rockchip_sfc_xfer_setup(sfc, mem, op, len);
+       if (len) {
+               if (likely(sfc->use_dma) && len >= SFC_DMA_TRANS_THRETHOLD) {
+                       init_completion(&sfc->cp);
+                       rockchip_sfc_irq_unmask(sfc, SFC_IMR_DMA);
+                       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);
+}
+
+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;
+}
+
+static const struct spi_controller_mem_ops rockchip_sfc_mem_ops = {
+       .exec_op = rockchip_sfc_exec_mem_op,
+       .adjust_op_size = rockchip_sfc_adjust_op_size,
+};
+
+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);
+
+               return IRQ_HANDLED;
+       }
+
+       return IRQ_NONE;
+}
+
+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->flags = SPI_MASTER_HALF_DUPLEX;
+       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->max_speed_hz = SFC_MAX_SPEED;
+       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);
+       sfc->version = rockchip_sfc_get_version(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,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@rock-chips.com>");
+MODULE_AUTHOR("Chris Morgan <macromorgan@hotmail.com>");
+MODULE_AUTHOR("Jon Lin <Jon.lin@rock-chips.com>");