[RFC v4 2/8] spi: rockchip-sfc: add rockchip serial flash controller

Chris Morgan
2021-06-04T15:12:49Z

Add the rockchip serial flash controller (SFC) driver.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
---
drivers/spi/Kconfig | 9 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-rockchip-sfc.c | 863 +++++++++++++++++++++++++++++++++
3 files changed, 873 insertions(+)
create mode 100644 drivers/spi/spi-rockchip-sfc.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index f4481fe48bf0..4d81ba7841e2 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..ddce87a2f319
--- /dev/null
+++ b/drivers/spi/spi-rockchip-sfc.c
@@ -0,0 +1,863 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// Rockchip Serial Flash Controller Driver
+//
+// Copyright (c) 2017, Rockchip Inc.
+// Author: Shawn Lin <shawn.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_COMMON_BITS_1 0x0
+#define SFC_CTRL_COMMON_BITS_2 0x1
+#define SFC_CTRL_COMMON_BITS_4 0x2
+#define SFC_CTRL_DATA_BITS_SHIFT 12
+#define SFC_CTRL_ADDR_BITS_SHIFT 10
+#define SFC_CTRL_CMD_BITS_SHIFT 8
+#define SFC_CTRL_PHASE_SEL_NEGETIVE BIT(1)
+
+/* 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)
+
+/* Master trigger */
+#define SFC_DMA_TRIGGER 0x80
+
+/* Src or Dst addr for master */
+#define SFC_DMA_ADDR 0x84
+
+/* Command */
+#define SFC_CMD 0x100
+#define SFC_CMD_IDX_SHIFT 0
+#define SFC_CMD_DUMMY_SHIFT 8
+#define SFC_CMD_DIR_RD 0
+#define SFC_CMD_DIR_WR 1
+#define SFC_CMD_DIR_SHIFT 12
+#define SFC_CMD_ADDR_ZERO (0x0 << 14)
+#define SFC_CMD_ADDR_24BITS (0x1 << 14)
+#define SFC_CMD_ADDR_32BITS (0x2 << 14)
+#define SFC_CMD_ADDR_FRS (0x3 << 14)
+#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_TRANS_BYTES (512 * 31)
+
+/* 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)
+
+#define SFC_CMD_DUMMY(x) \
+ ((x) << SFC_CMD_DUMMY_SHIFT)
+
+enum rockchip_sfc_iftype {
+ IF_TYPE_STD,
+ IF_TYPE_DUAL,
+ IF_TYPE_QUAD,
+};
+
+struct rockchip_sfc;
+struct rockchip_sfc_chip_priv {
+ u8 cs;
+ u32 clk_rate;
+ struct rockchip_sfc *sfc;
+};
+
+struct rockchip_sfc {
+ struct device *dev;
+ void __iomem *regbase;
+ struct clk *hclk;
+ struct clk *clk;
+ /* virtual mapped addr for dma_buffer */
+ void *buffer;
+ dma_addr_t dma_buffer;
+ struct completion cp;
+ struct rockchip_sfc_chip_priv flash[SFC_MAX_CHIPSELECT_NUM];
+ u8 num_chip;
+ bool use_dma;
+};
+
+static int rockchip_sfc_get_if_type(const struct spi_mem_op *op,
+ struct rockchip_sfc *sfc)
+{
+ switch (op->data.buswidth) {
+ case 1:
+ return IF_TYPE_STD;
+ case 2:
+ return IF_TYPE_DUAL;
+ case 4:
+ return IF_TYPE_QUAD;
+ default:
+ dev_err(sfc->dev, "unsupported SPI read mode\n");
+ return -EINVAL;
+ }
+}
+
+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(SFC_ICLR_RX_FULL | SFC_ICLR_RX_UFLOW |
+ SFC_ICLR_TX_OFLOW | SFC_ICLR_TX_EMPTY |
+ SFC_ICLR_TRAN_FINISH | SFC_ICLR_BUS_ERR |
+ SFC_ICLR_NSPI_ERR | SFC_ICLR_DMA,
+ sfc->regbase + SFC_ICLR);
+
+ dev_dbg(sfc->dev, "reset\n");
+
+ return err;
+}
+
+static int rockchip_sfc_init(struct rockchip_sfc *sfc)
+{
+ int err;
+
+ err = clk_set_rate(sfc->clk, SFC_DEFAULT_SPEED_HZ);
+ if (err)
+ return err;
+
+ err = rockchip_sfc_reset(sfc);
+ if (err)
+ return err;
+
+ /* Mask all eight interrupts */
+ writel_relaxed(0xff, sfc->regbase + SFC_IMR);
+
+ writel_relaxed(SFC_CTRL_PHASE_SEL_NEGETIVE, sfc->regbase + SFC_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;
+}
+
+/* The SFC_CTRL register is a global control register,
+ * when the controller is in busy state(SFC_SR),
+ * SFC_CTRL cannot be set.
+ */
+static void rockchip_sfc_wait_idle(struct rockchip_sfc *sfc, u32 timeout_us)
+{
+ u32 status;
+ int ret;
+
+ 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);
+ }
+}
+
+static void rockchip_sfc_setup_ctrl(struct rockchip_sfc *sfc)
+{
+ u32 reg;
+
+ reg = IF_TYPE_STD << SFC_CTRL_DATA_BITS_SHIFT;
+ reg |= IF_TYPE_STD << SFC_CTRL_ADDR_BITS_SHIFT;
+ reg |= IF_TYPE_STD << SFC_CTRL_CMD_BITS_SHIFT;
+ reg |= SFC_CTRL_PHASE_SEL_NEGETIVE;
+
+ rockchip_sfc_wait_idle(sfc, 10000);
+
+ writel_relaxed(reg, sfc->regbase + SFC_CTRL);
+}
+
+static int rockchip_sfc_op_reg(struct rockchip_sfc_chip_priv *priv,
+ u8 opcode, int len, u8 optype)
+{
+ struct rockchip_sfc *sfc = priv->sfc;
+ u32 reg;
+
+ rockchip_sfc_setup_ctrl(sfc);
+
+ reg = opcode << SFC_CMD_IDX_SHIFT;
+ reg |= len << SFC_CMD_TRAN_BYTES_SHIFT;
+ reg |= priv->cs << SFC_CMD_CS_SHIFT;
+ reg |= optype << SFC_CMD_DIR_SHIFT;
+ writel_relaxed(reg, sfc->regbase + SFC_CMD);
+
+ 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 of the bytes that are not a multiple of word size */
+ 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_relaxed(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 of the bytes that are not a multiple of word size */
+ 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_read_reg(struct rockchip_sfc_chip_priv *priv,
+ const struct spi_mem_op *op)
+{
+ struct rockchip_sfc *sfc = priv->sfc;
+ int ret;
+ int trans;
+ size_t n_rx = op->data.nbytes;
+ u8 opcode = op->cmd.opcode;
+ u8 *rxbuf = op->data.buf.in;
+
+ trans = min_t(int, n_rx, SFC_MAX_TRANS_BYTES);
+ ret = rockchip_sfc_op_reg(priv, opcode, trans, SFC_CMD_DIR_RD);
+ if (ret)
+ return ret;
+
+ ret = rockchip_sfc_read_fifo(sfc, rxbuf, trans);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int rockchip_sfc_write_reg(struct rockchip_sfc_chip_priv *priv,
+ const struct spi_mem_op *op)
+{
+ struct rockchip_sfc *sfc = priv->sfc;
+ int ret;
+ size_t n_tx = op->data.nbytes;
+ u8 opcode = op->cmd.opcode;
+ const u8 *txbuf = op->data.buf.out;
+
+ ret = rockchip_sfc_op_reg(priv, opcode, n_tx, SFC_CMD_DIR_WR);
+ if (ret)
+ return ret;
+ ret = rockchip_sfc_write_fifo(sfc, txbuf, n_tx);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int rockchip_sfc_setup_transfer(struct rockchip_sfc_chip_priv *priv,
+ const struct spi_mem_op *op,
+ loff_t from_to, size_t len, u8 op_type)
+{
+ struct rockchip_sfc *sfc = priv->sfc;
+ u8 if_type = IF_TYPE_STD;
+ u8 addr_width = op->addr.nbytes;
+ u8 read_dummy_bits = op->dummy.nbytes << 3;
+ u32 reg;
+
+ if (op_type == SFC_CMD_DIR_RD)
+ if_type = rockchip_sfc_get_if_type(op, sfc);
+
+ rockchip_sfc_wait_idle(sfc, 10000);
+
+ writel_relaxed((if_type << SFC_CTRL_DATA_BITS_SHIFT) |
+ (IF_TYPE_STD << SFC_CTRL_ADDR_BITS_SHIFT) |
+ (IF_TYPE_STD << SFC_CTRL_CMD_BITS_SHIFT) |
+ SFC_CTRL_PHASE_SEL_NEGETIVE,
+ sfc->regbase + SFC_CTRL);
+
+ reg = op->cmd.opcode << SFC_CMD_IDX_SHIFT;
+
+ reg |= op_type << SFC_CMD_DIR_SHIFT;
+ reg |= (addr_width == 4) ?
+ SFC_CMD_ADDR_32BITS : SFC_CMD_ADDR_24BITS;
+
+ reg |= priv->cs << SFC_CMD_CS_SHIFT;
+ reg |= len << SFC_CMD_TRAN_BYTES_SHIFT;
+
+ if (op_type == SFC_CMD_DIR_RD)
+ reg |= SFC_CMD_DUMMY(read_dummy_bits);
+
+ writel_relaxed(reg, sfc->regbase + SFC_CMD);
+ writel_relaxed(from_to, sfc->regbase + SFC_ADDR);
+
+ return 0;
+}
+
+static int rockchip_sfc_do_dma_transfer(struct rockchip_sfc_chip_priv *priv,
+ const struct spi_mem_op *op, loff_t from_to,
+ dma_addr_t dma_buf, size_t len, u8 op_type)
+{
+ struct rockchip_sfc *sfc = priv->sfc;
+ u32 reg;
+ int err = 0;
+
+ init_completion(&sfc->cp);
+
+ writel_relaxed(SFC_ICLR_RX_FULL | SFC_ICLR_RX_UFLOW |
+ SFC_ICLR_TX_OFLOW | SFC_ICLR_TX_EMPTY |
+ SFC_ICLR_TRAN_FINISH | SFC_ICLR_BUS_ERR |
+ SFC_ICLR_NSPI_ERR | SFC_ICLR_DMA,
+ sfc->regbase + SFC_ICLR);
+
+ /* Enable transfer complete interrupt */
+ reg = readl_relaxed(sfc->regbase + SFC_IMR);
+ reg &= ~SFC_IMR_TRAN_FINISH;
+ writel_relaxed(reg, sfc->regbase + SFC_IMR);
+
+ err = rockchip_sfc_setup_transfer(priv, op, from_to, len, op_type);
+ if (err < 0)
+ return err;
+
+ writel_relaxed(dma_buf, sfc->regbase + SFC_DMA_ADDR);
+
+ /*
+ * Start dma but note that the sfc->dma_buffer is derived from
+ * dmam_alloc_coherent so we don't actually need any sync operations
+ * for coherent dma memory.
+ */
+ 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_relaxed(SFC_ICLR_RX_FULL | SFC_ICLR_RX_UFLOW |
+ SFC_ICLR_TX_OFLOW | SFC_ICLR_TX_EMPTY |
+ SFC_ICLR_TRAN_FINISH | SFC_ICLR_BUS_ERR |
+ SFC_ICLR_NSPI_ERR | SFC_ICLR_DMA,
+ sfc->regbase + SFC_ICLR);
+ /* Disable transfer finish interrupt */
+ reg = readl_relaxed(sfc->regbase + SFC_IMR);
+ reg |= SFC_IMR_TRAN_FINISH;
+ writel_relaxed(reg, sfc->regbase + SFC_IMR);
+
+ if (err) {
+ rockchip_sfc_reset(sfc);
+ return err;
+ }
+
+ return 0;
+}
+
+static inline int rockchip_sfc_pio_write(struct rockchip_sfc *sfc, u_char *buf,
+ size_t len)
+{
+ return rockchip_sfc_write_fifo(sfc, buf, len);
+}
+
+static inline int rockchip_sfc_pio_read(struct rockchip_sfc *sfc, u_char *buf,
+ size_t len)
+{
+ return rockchip_sfc_read_fifo(sfc, buf, len);
+}
+
+static int rockchip_sfc_pio_transfer(struct rockchip_sfc_chip_priv *priv,
+ const struct spi_mem_op *op, loff_t from_to, size_t len,
+ u_char *buf, u8 op_type)
+{
+ struct rockchip_sfc *sfc = priv->sfc;
+ size_t trans;
+ int ret;
+
+ trans = min_t(size_t, SFC_MAX_TRANS_BYTES, len);
+ ret = rockchip_sfc_setup_transfer(priv, op, from_to, trans, op_type);
+ if (ret < 0)
+ return ret;
+
+ if (op_type == SFC_CMD_DIR_WR)
+ ret = rockchip_sfc_pio_write(sfc, buf, trans);
+ else
+ ret = rockchip_sfc_pio_read(sfc, buf, trans);
+
+ return ret;
+}
+
+static int rockchip_sfc_dma_transfer(struct rockchip_sfc_chip_priv *priv,
+ const struct spi_mem_op *op, loff_t from_to, size_t len,
+ u_char *buf, u8 op_type)
+{
+ struct rockchip_sfc *sfc = priv->sfc;
+ size_t trans;
+ int ret;
+
+ trans = min_t(size_t, SFC_MAX_TRANS_BYTES, len);
+
+ if (op_type == SFC_CMD_DIR_WR)
+ memcpy(sfc->buffer, buf, trans);
+
+ ret = rockchip_sfc_do_dma_transfer(priv, op, from_to, sfc->dma_buffer,
+ trans, op_type);
+ if (ret) {
+ dev_warn(sfc->dev, "DMA timeout\n");
+ return ret;
+ }
+
+ if (op_type == SFC_CMD_DIR_RD)
+ memcpy(buf, sfc->buffer, trans);
+
+ return trans;
+}
+
+static ssize_t rockchip_sfc_do_rd_wr(struct rockchip_sfc_chip_priv *priv,
+ const struct spi_mem_op *op, loff_t from_to, size_t len,
+ u_char *buf, u32 op_type)
+{
+ struct rockchip_sfc *sfc = priv->sfc;
+
+ /* DMA can only handle word aligned transfer chunks */
+ if (likely(sfc->use_dma) && !(len & 0x3))
+ return rockchip_sfc_dma_transfer(priv, op, from_to, len, buf, op_type);
+ else
+ return rockchip_sfc_pio_transfer(priv, op, from_to, len, buf, op_type);
+}
+
+static ssize_t rockchip_sfc_read(struct rockchip_sfc_chip_priv *priv,
+ const struct spi_mem_op *op)
+{
+ loff_t from = op->addr.val;
+ size_t len = op->data.nbytes;
+ u_char *read_buf = op->data.buf.in;
+
+ return rockchip_sfc_do_rd_wr(priv, op, from, len, read_buf, SFC_CMD_DIR_RD);
+}
+
+static ssize_t rockchip_sfc_write(struct rockchip_sfc_chip_priv *priv,
+ const struct spi_mem_op *op)
+{
+ loff_t to = op->addr.val;
+ size_t len = op->data.nbytes;
+ const u_char *write_buf = op->data.buf.out;
+
+ return rockchip_sfc_do_rd_wr(priv, op, to, len, (u_char *)write_buf, SFC_CMD_DIR_WR);
+}
+
+static int rockchip_sfc_mem_process(struct spi_mem *mem, const struct spi_mem_op *op)
+{
+ struct rockchip_sfc *sfc = spi_master_get_devdata(mem->spi->master);
+ struct rockchip_sfc_chip_priv *priv = &sfc->flash[mem->spi->chip_select];
+
+ if (op->data.dir == SPI_MEM_DATA_IN && op->data.buf.in) {
+ if (!op->addr.nbytes)
+ return rockchip_sfc_read_reg(priv, op);
+
+ return rockchip_sfc_read(priv, op);
+ }
+
+ if (!op->addr.nbytes || !op->data.buf.out)
+ return rockchip_sfc_write_reg(priv, op);
+
+ return rockchip_sfc_write(priv, op);
+}
+
+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);
+ struct rockchip_sfc_chip_priv *priv = &sfc->flash[mem->spi->chip_select];
+ int ret;
+
+ ret = clk_set_rate(sfc->clk, priv->clk_rate);
+ if (ret)
+ return ret;
+
+ ret = rockchip_sfc_mem_process(mem, op);
+ if (ret < 0) {
+ dev_err(&mem->spi->dev, "operation failed with %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static const char *rockchip_sfc_get_name(struct spi_mem *mem)
+{
+ struct rockchip_sfc *sfc = spi_master_get_devdata(mem->spi->master);
+ struct device *dev = sfc->dev;
+
+ return devm_kasprintf(dev, GFP_KERNEL, "%s.%d", dev_name(dev), mem->spi->chip_select);
+}
+
+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 int rockchip_sfc_register(struct device_node *np,
+ struct rockchip_sfc *sfc)
+{
+ struct device *dev = sfc->dev;
+ int ret;
+
+ ret = of_property_read_u8(np, "reg", &sfc->flash[sfc->num_chip].cs);
+ if (ret) {
+ dev_err(dev, "No reg property for %s\n",
+ np->full_name);
+ return ret;
+ }
+
+ ret = of_property_read_u32(np, "spi-max-frequency",
+ &sfc->flash[sfc->num_chip].clk_rate);
+ if (ret) {
+ dev_err(dev, "No spi-max-frequency property for %s\n",
+ np->full_name);
+ return ret;
+ }
+
+ sfc->flash[sfc->num_chip].sfc = sfc;
+ sfc->num_chip++;
+ return 0;
+}
+
+static int rockchip_sfc_register_all(struct rockchip_sfc *sfc)
+{
+ struct device *dev = sfc->dev;
+ struct device_node *np;
+ int ret;
+
+ for_each_available_child_of_node(dev->of_node, np) {
+ ret = rockchip_sfc_register(np, sfc);
+ if (ret)
+ dev_err(dev, "Failed to register all chips\n");
+ return ret;
+
+ if (sfc->num_chip >= SFC_MAX_CHIPSELECT_NUM) {
+ dev_warn(dev, "Exceeds the max cs limitation\n");
+ break;
+ }
+ }
+
+ return 0;
+}
+
+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 if transfer is finished */
+ if (reg & SFC_RISR_TRAN_FINISH) {
+ writel_relaxed(reg, sfc->regbase + SFC_ICLR);
+ 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 = spi_alloc_master(&pdev->dev, sizeof(*sfc));
+ if (!master) {
+ dev_err(&pdev->dev, "spi_alloc_master failed\n");
+ return -ENOMEM;
+ }
+
+ master->mem_ops = &rockchip_sfc_mem_ops;
+ master->dev.of_node = pdev->dev.of_node;
+ master->mode_bits = SPI_RX_QUAD | SPI_RX_DUAL;
+ master->min_speed_hz = SFC_MIN_SPEED_HZ;
+ master->max_speed_hz = SFC_MAX_SPEED_HZ;
+
+ 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, "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, "ahb");
+ 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_TRANS_BYTES,
+ &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");
+ goto err_irq;
+ }
+
+ sfc->num_chip = 0;
+ ret = rockchip_sfc_init(sfc);
+ if (ret)
+ goto err_irq;
+
+ ret = rockchip_sfc_register_all(sfc);
+ if (ret)
+ goto err_irq;
+
+ ret = devm_spi_register_master(dev, 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 rockchip_sfc *sfc = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(sfc->clk);
+ clk_disable_unprepare(sfc->hclk);
+ return 0;
+}
+
+static const struct of_device_id rockchip_sfc_dt_ids[] = {
+ { .compatible = "rockchip,rk3036-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>");