[PATCH 1/2] spi: Add Renesas R-Car RPC SPI controller driver

[Mason Yang <masonccyang@xxxxxxxxxxx>]

Add a driver for Renesas R-Car D3 RPC SPI controller driver.

Signed-off-by: Mason Yang <masonccyang@xxxxxxxxxxx>
---
 drivers/spi/Kconfig           |   6 +
 drivers/spi/Makefile          |   1 +
 drivers/spi/spi-renesas-rpc.c | 750 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 757 insertions(+)
 create mode 100644 drivers/spi/spi-renesas-rpc.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 7d3a5c9..093006a 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -528,6 +528,12 @@ config SPI_RSPI
 	help
 	  SPI driver for Renesas RSPI and QSPI blocks.
 
+config SPI_RENESAS_RPC
+	tristate "Renesas R-Car D3 RPC SPI controller"
+	depends on SUPERH || ARCH_RENESAS || COMPILE_TEST
+	help
+	  SPI driver for Renesas R-Car D3 RPC.
+
 config SPI_QCOM_QSPI
 	tristate "QTI QSPI controller"
 	depends on ARCH_QCOM
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 3575205..5d5c523 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -81,6 +81,7 @@ obj-$(CONFIG_SPI_QUP)			+= spi-qup.o
 obj-$(CONFIG_SPI_ROCKCHIP)		+= spi-rockchip.o
 obj-$(CONFIG_SPI_RB4XX)			+= spi-rb4xx.o
 obj-$(CONFIG_SPI_RSPI)			+= spi-rspi.o
+obj-$(CONFIG_SPI_RENESAS_RPC)		+= spi-renesas-rpc.o
 obj-$(CONFIG_SPI_S3C24XX)		+= spi-s3c24xx-hw.o
 spi-s3c24xx-hw-y			:= spi-s3c24xx.o
 spi-s3c24xx-hw-$(CONFIG_SPI_S3C24XX_FIQ) += spi-s3c24xx-fiq.o
diff --git a/drivers/spi/spi-renesas-rpc.c b/drivers/spi/spi-renesas-rpc.c
new file mode 100644
index 0000000..00b9d8f
--- /dev/null
+++ b/drivers/spi/spi-renesas-rpc.c
@@ -0,0 +1,750 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (C) 2018 ~ 2019 Renesas Solutions Corp.
+// Copyright (C) 2018 Macronix International Co., Ltd.
+//
+// R-Car D3 RPC SPI/QSPI/Octa driver
+//
+// Authors:
+//	Mason Yang <masonccyang@xxxxxxxxxxx>
+//
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi-mem.h>
+
+#define RPC_CMNCR		0x0000	/* R/W */
+#define RPC_CMNCR_MD		BIT(31)
+#define RPC_CMNCR_SFDE		BIT(24)
+#define RPC_CMNCR_MOIIO3(val)	(((val) & 0x3) << 22)
+#define RPC_CMNCR_MOIIO2(val)	(((val) & 0x3) << 20)
+#define RPC_CMNCR_MOIIO1(val)	(((val) & 0x3) << 18)
+#define RPC_CMNCR_MOIIO0(val)	(((val) & 0x3) << 16)
+#define RPC_CMNCR_MOIIO_HIZ	(RPC_CMNCR_MOIIO0(3) | RPC_CMNCR_MOIIO1(3) | \
+				 RPC_CMNCR_MOIIO2(3) | RPC_CMNCR_MOIIO3(3))
+#define RPC_CMNCR_IO3FV(val)	(((val) & 0x3) << 14)
+#define RPC_CMNCR_IO2FV(val)	(((val) & 0x3) << 12)
+#define RPC_CMNCR_IO0FV(val)	(((val) & 0x3) << 8)
+#define RPC_CMNCR_IOFV_HIZ	(RPC_CMNCR_IO0FV(3) | RPC_CMNCR_IO2FV(3) | \
+				 RPC_CMNCR_IO3FV(3))
+#define RPC_CMNCR_CPHAT		BIT(6)
+#define RPC_CMNCR_CPHAR		BIT(5)
+#define RPC_CMNCR_SSLP		BIT(4)
+#define RPC_CMNCR_CPOL		BIT(3)
+#define RPC_CMNCR_BSZ(val)	(((val) & 0x3) << 0)
+
+#define RPC_SSLDR		0x0004	/* R/W */
+#define RPC_SSLDR_SPNDL(d)	(((d) & 0x7) << 16)
+#define RPC_SSLDR_SLNDL(d)	(((d) & 0x7) << 8)
+#define RPC_SSLDR_SCKDL(d)	(((d) & 0x7) << 0)
+
+#define RPC_DRCR		0x000C	/* R/W */
+#define RPC_DRCR_SSLN		BIT(24)
+#define RPC_DRCR_RBURST(v)	(((v) & 0x1F) << 16)
+#define RPC_DRCR_RCF		BIT(9)
+#define RPC_DRCR_RBE		BIT(8)
+#define RPC_DRCR_SSLE		BIT(0)
+
+#define RPC_DRCMR		0x0010	/* R/W */
+#define RPC_DRCMR_CMD(c)	(((c) & 0xFF) << 16)
+#define RPC_DRCMR_OCMD(c)	(((c) & 0xFF) << 0)
+
+#define RPC_DREAR		0x0014	/* R/W */
+#define RPC_DREAR_EAC		BIT(0)
+
+#define RPC_DROPR		0x0018	/* R/W */
+
+#define RPC_DRENR		0x001C	/* R/W */
+#define RPC_DRENR_CDB(o)	(u32)((((o) & 0x3) << 30))
+#define RPC_DRENR_OCDB(o)	(((o) & 0x3) << 28)
+#define RPC_DRENR_ADB(o)	(((o) & 0x3) << 24)
+#define RPC_DRENR_OPDB(o)	(((o) & 0x3) << 20)
+#define RPC_DRENR_SPIDB(o)	(((o) & 0x3) << 16)
+#define RPC_DRENR_DME		BIT(15)
+#define RPC_DRENR_CDE		BIT(14)
+#define RPC_DRENR_OCDE		BIT(12)
+#define RPC_DRENR_ADE(v)	(((v) & 0xF) << 8)
+#define RPC_DRENR_OPDE(v)	(((v) & 0xF) << 4)
+
+#define RPC_SMCR		0x0020	/* R/W */
+#define RPC_SMCR_SSLKP		BIT(8)
+#define RPC_SMCR_SPIRE		BIT(2)
+#define RPC_SMCR_SPIWE		BIT(1)
+#define RPC_SMCR_SPIE		BIT(0)
+
+#define RPC_SMCMR		0x0024	/* R/W */
+#define RPC_SMCMR_CMD(c)	(((c) & 0xFF) << 16)
+#define RPC_SMCMR_OCMD(c)	(((c) & 0xFF) << 0)
+
+#define RPC_SMADR		0x0028	/* R/W */
+#define RPC_SMOPR		0x002C	/* R/W */
+#define RPC_SMOPR_OPD0(o)	(((o) & 0xFF) << 0)
+#define RPC_SMOPR_OPD1(o)	(((o) & 0xFF) << 8)
+#define RPC_SMOPR_OPD2(o)	(((o) & 0xFF) << 16)
+#define RPC_SMOPR_OPD3(o)	(((o) & 0xFF) << 24)
+
+#define RPC_SMENR		0x0030	/* R/W */
+#define RPC_SMENR_CDB(o)	(((o) & 0x2) << 30)
+#define RPC_SMENR_OCDB(o)	(((o) & 0x2) << 28)
+#define RPC_SMENR_ADB(o)	(((o) & 0x2) << 24)
+#define RPC_SMENR_OPDB(o)	(((o) & 0x2) << 20)
+#define RPC_SMENR_SPIDB(o)	(((o) & 0x2) << 16)
+#define RPC_SMENR_DME		BIT(15)
+#define RPC_SMENR_CDE		BIT(14)
+#define RPC_SMENR_OCDE		BIT(12)
+#define RPC_SMENR_ADE(v)	(((v) & 0xF) << 8)
+#define RPC_SMENR_OPDE(v)	(((v) & 0xF) << 4)
+#define RPC_SMENR_SPIDE(v)	(((v) & 0xF) << 0)
+
+#define RPC_SMRDR0		0x0038	/* R */
+#define RPC_SMRDR1		0x003C	/* R */
+#define RPC_SMWDR0		0x0040	/* W */
+#define RPC_SMWDR1		0x0044	/* W */
+
+#define RPC_CMNSR		0x0048	/* R */
+#define RPC_CMNSR_SSLF		BIT(1)
+#define	RPC_CMNSR_TEND		BIT(0)
+
+#define RPC_DRDMCR		0x0058	/* R/W */
+#define RPC_DRDRENR		0x005C	/* R/W */
+
+#define RPC_SMDMCR		0x0060	/* R/W */
+#define RPC_SMDMCR_DMCYC(v)	((((v) - 1) & 0x1F) << 0)
+
+#define RPC_SMDRENR		0x0064	/* R/W */
+#define RPC_SMDRENR_HYPE	(0x5 << 12)
+#define RPC_SMDRENR_ADDRE	BIT(8)
+#define RPC_SMDRENR_OPDRE	BIT(4)
+#define RPC_SMDRENR_SPIDRE	BIT(0)
+
+#define RPC_PHYCNT		0x007C	/* R/W */
+#define RPC_PHYCNT_CAL		BIT(31)
+#define PRC_PHYCNT_OCTA_AA	BIT(22)
+#define PRC_PHYCNT_OCTA_SA	BIT(23)
+#define PRC_PHYCNT_EXDS		BIT(21)
+#define RPC_PHYCNT_OCT		BIT(20)
+#define RPC_PHYCNT_STRTIM(v)	(((v) & 0x7) << 15)
+#define RPC_PHYCNT_WBUF2	BIT(4)
+#define RPC_PHYCNT_WBUF		BIT(2)
+#define RPC_PHYCNT_MEM(v)	(((v) & 0x3) << 0)
+
+#define RPC_PHYOFFSET1		0x0080	/* R/W */
+#define RPC_PHYOFFSET2		0x0084	/* R/W */
+
+#define RPC_WBUF		0x8000	/* Write Buffer */
+#define RPC_WBUF_SIZE		256	/* Write Buffer size */
+
+struct rpc_spi {
+	struct clk *clk_rpc;
+	void __iomem *regs;
+	struct {
+		void __iomem *map;
+		dma_addr_t dma;
+		size_t size;
+	} linear;
+	u32 cur_speed_hz;
+	u32 cmd;
+	u32 addr;
+	u32 dummy;
+	u32 smcr;
+	u32 smenr;
+	u32 xferlen;
+	u32 totalxferlen;
+	enum spi_mem_data_dir xfer_dir;
+};
+
+static int rpc_spi_set_freq(struct rpc_spi *rpc, unsigned long freq)
+{
+	int ret;
+
+	if (rpc->cur_speed_hz == freq)
+		return 0;
+
+	clk_disable_unprepare(rpc->clk_rpc);
+	ret = clk_set_rate(rpc->clk_rpc, freq);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(rpc->clk_rpc);
+	if (ret)
+		return ret;
+
+	rpc->cur_speed_hz = freq;
+	return ret;
+}
+
+static void rpc_spi_hw_init(struct rpc_spi *rpc)
+{
+	/*
+	 * NOTE: The 0x260 are undocumented bits, but they must be set.
+	 */
+	writel(RPC_PHYCNT_CAL | RPC_PHYCNT_STRTIM(0x3) | 0x260,
+	       rpc->regs + RPC_PHYCNT);
+
+	/*
+	 * NOTE: The 0x31511144 and 0x431 are undocumented bits,
+	 *	 but they must be set for RPC_PHYOFFSET1 & RPC_PHYOFFSET2.
+	 */
+	writel(0x31511144, rpc->regs + RPC_PHYOFFSET1);
+	writel(0x431, rpc->regs + RPC_PHYOFFSET2);
+
+	writel(RPC_SSLDR_SPNDL(7) | RPC_SSLDR_SLNDL(7) |
+	       RPC_SSLDR_SCKDL(7), rpc->regs + RPC_SSLDR);
+}
+
+static int wait_msg_xfer_end(struct rpc_spi *rpc)
+{
+	u32 sts;
+
+	return readl_poll_timeout(rpc->regs + RPC_CMNSR, sts,
+				  sts & RPC_CMNSR_TEND, 0, USEC_PER_SEC);
+}
+
+static u8 rpc_bits_xfer(u32 nbytes)
+{
+	u8 databyte;
+
+	switch (nbytes) {
+	case 1:
+		databyte = 0x8;
+		break;
+	case 2:
+		databyte = 0xc;
+		break;
+	default:
+		databyte = 0xf;
+		break;
+	}
+
+	return databyte;
+}
+
+static int rpc_spi_io_xfer(struct rpc_spi *rpc,
+			   const void *tx_buf, void *rx_buf)
+{
+	u32 smenr, smcr, data, pos = 0;
+	int ret = 0;
+
+	writel(RPC_CMNCR_MD | RPC_CMNCR_SFDE | RPC_CMNCR_MOIIO_HIZ |
+	       RPC_CMNCR_IOFV_HIZ | RPC_CMNCR_BSZ(0), rpc->regs + RPC_CMNCR);
+	writel(0x0, rpc->regs + RPC_SMDRENR);
+
+	if (tx_buf) {
+		writel(rpc->cmd, rpc->regs + RPC_SMCMR);
+		writel(rpc->dummy, rpc->regs + RPC_SMDMCR);
+		writel(rpc->addr, rpc->regs + RPC_SMADR);
+		smenr = rpc->smenr;
+
+		while (pos < rpc->xferlen) {
+			u32 nbytes = rpc->xferlen  - pos;
+
+			writel(*(u32 *)(tx_buf + pos), rpc->regs + RPC_SMWDR0);
+
+			if (nbytes > 4) {
+				nbytes = 4;
+				smcr = rpc->smcr |
+				       RPC_SMCR_SPIE | RPC_SMCR_SSLKP;
+			} else {
+				smcr = rpc->smcr | RPC_SMCR_SPIE;
+			}
+
+			writel(smenr, rpc->regs + RPC_SMENR);
+			writel(smcr, rpc->regs + RPC_SMCR);
+			ret = wait_msg_xfer_end(rpc);
+			if (ret)
+				goto out;
+
+			pos += nbytes;
+			smenr = rpc->smenr & ~RPC_SMENR_CDE &
+					     ~RPC_SMENR_ADE(0xf);
+		}
+	} else if (rx_buf) {
+		while (pos < rpc->xferlen) {
+			u32 nbytes = rpc->xferlen  - pos;
+
+			if (nbytes > 4)
+				nbytes = 4;
+
+			writel(rpc->cmd, rpc->regs + RPC_SMCMR);
+			writel(rpc->dummy, rpc->regs + RPC_SMDMCR);
+			writel(rpc->addr + pos, rpc->regs + RPC_SMADR);
+			writel(rpc->smenr, rpc->regs + RPC_SMENR);
+			writel(rpc->smcr | RPC_SMCR_SPIE, rpc->regs + RPC_SMCR);
+			ret = wait_msg_xfer_end(rpc);
+			if (ret)
+				goto out;
+
+			data = readl(rpc->regs + RPC_SMRDR0);
+			memcpy_fromio(rx_buf + pos, (void *)&data, nbytes);
+			pos += nbytes;
+		}
+	} else {
+		writel(rpc->cmd, rpc->regs + RPC_SMCMR);
+		writel(rpc->dummy, rpc->regs + RPC_SMDMCR);
+		writel(rpc->addr + pos, rpc->regs + RPC_SMADR);
+		writel(rpc->smenr, rpc->regs + RPC_SMENR);
+		writel(rpc->smcr | RPC_SMCR_SPIE, rpc->regs + RPC_SMCR);
+		ret = wait_msg_xfer_end(rpc);
+	}
+out:
+	return ret;
+}
+
+static void rpc_spi_mem_set_prep_op_cfg(struct spi_device *spi,
+					const struct spi_mem_op *op,
+					u64 *offs, size_t *len)
+{
+	struct rpc_spi *rpc = spi_master_get_devdata(spi->master);
+
+	rpc->cmd = RPC_SMCMR_CMD(op->cmd.opcode);
+	rpc->smenr = RPC_SMENR_CDE |
+		     RPC_SMENR_CDB(fls(op->cmd.buswidth >> 1));
+	rpc->totalxferlen = 1;
+	rpc->xferlen = 0;
+	rpc->addr = 0;
+
+	if (op->addr.nbytes) {
+		rpc->smenr |= RPC_SMENR_ADB(fls(op->addr.buswidth >> 1));
+		if (op->addr.nbytes == 4)
+			rpc->smenr |= RPC_SMENR_ADE(0xf);
+		else
+			rpc->smenr |= RPC_SMENR_ADE(0x7);
+
+		if (!offs && !len)
+			rpc->addr = *(u32 *)offs;
+		else
+			rpc->addr = op->addr.val;
+		rpc->totalxferlen += op->addr.nbytes;
+	}
+
+	if (op->dummy.nbytes) {
+		rpc->smenr |= RPC_SMENR_DME;
+		rpc->dummy = RPC_SMDMCR_DMCYC(op->dummy.nbytes);
+		rpc->totalxferlen += op->dummy.nbytes;
+	}
+
+	if (op->data.nbytes || (offs && len)) {
+		rpc->smenr |= RPC_SMENR_SPIDE(rpc_bits_xfer(op->data.nbytes)) |
+			      RPC_SMENR_SPIDB(fls(op->data.buswidth >> 1));
+
+		if (op->data.dir == SPI_MEM_DATA_IN) {
+			rpc->smcr = RPC_SMCR_SPIRE;
+			rpc->xfer_dir = SPI_MEM_DATA_IN;
+		} else if (op->data.dir == SPI_MEM_DATA_OUT) {
+			rpc->smcr = RPC_SMCR_SPIWE;
+			rpc->xfer_dir = SPI_MEM_DATA_OUT;
+		}
+
+		if (offs && len) {
+			rpc->xferlen = *(u32 *)len;
+			rpc->totalxferlen += *(u32 *)len;
+		} else {
+			rpc->xferlen = op->data.nbytes;
+			rpc->totalxferlen += op->data.nbytes;
+		}
+	}
+}
+
+static bool rpc_spi_mem_supports_op(struct spi_mem *mem,
+				    const struct spi_mem_op *op)
+{
+	if (op->data.buswidth > 4 || op->addr.buswidth > 4 ||
+	    op->dummy.buswidth > 4 || op->cmd.buswidth > 4)
+		return false;
+
+	if (op->addr.nbytes > 4)
+		return false;
+
+	return true;
+}
+
+static ssize_t rpc_spi_mem_dirmap_read(struct spi_mem_dirmap_desc *desc,
+				       u64 offs, size_t len, void *buf)
+{
+	struct rpc_spi *rpc = spi_master_get_devdata(desc->mem->spi->master);
+	int ret;
+
+	if (WARN_ON(offs + desc->info.offset + len > U32_MAX))
+		return -EINVAL;
+
+	ret = rpc_spi_set_freq(rpc, desc->mem->spi->max_speed_hz);
+	if (ret)
+		return ret;
+
+	rpc_spi_mem_set_prep_op_cfg(desc->mem->spi,
+				    &desc->info.op_tmpl, &offs, &len);
+
+	writel(RPC_CMNCR_SFDE | RPC_CMNCR_MOIIO_HIZ |
+	       RPC_CMNCR_IOFV_HIZ | RPC_CMNCR_BSZ(0), rpc->regs + RPC_CMNCR);
+
+	writel(RPC_DRCR_RBURST(0x1f) | RPC_DRCR_RBE, rpc->regs + RPC_DRCR);
+	writel(rpc->cmd, rpc->regs + RPC_DRCMR);
+	writel(RPC_DREAR_EAC, rpc->regs + RPC_DREAR);
+	writel(0, rpc->regs + RPC_DROPR);
+	writel(rpc->smenr, rpc->regs + RPC_DRENR);
+	writel(rpc->dummy, rpc->regs + RPC_DRDMCR);
+	writel(0x0, rpc->regs + RPC_DRDRENR);
+	memcpy_fromio(buf, rpc->linear.map + desc->info.offset + offs, len);
+
+	return len;
+}
+
+static ssize_t rpc_spi_mem_dirmap_write(struct spi_mem_dirmap_desc *desc,
+					u64 offs, size_t len, const void *buf)
+{
+	struct rpc_spi *rpc = spi_master_get_devdata(desc->mem->spi->master);
+	int tx_offs, ret;
+
+	if (WARN_ON(offs + desc->info.offset + len > U32_MAX))
+		return -EINVAL;
+
+	if (WARN_ON(len > RPC_WBUF_SIZE))
+		return -EIO;
+
+	ret = rpc_spi_set_freq(rpc, desc->mem->spi->max_speed_hz);
+	if (ret)
+		return ret;
+
+	rpc_spi_mem_set_prep_op_cfg(desc->mem->spi,
+				    &desc->info.op_tmpl, &offs, &len);
+
+	writel(RPC_CMNCR_MD | RPC_CMNCR_SFDE | RPC_CMNCR_MOIIO_HIZ |
+	       RPC_CMNCR_IOFV_HIZ | RPC_CMNCR_BSZ(0), rpc->regs + RPC_CMNCR);
+	writel(0x0, rpc->regs + RPC_SMDRENR);
+
+	writel(RPC_PHYCNT_CAL | 0x260 | RPC_PHYCNT_WBUF2 | RPC_PHYCNT_WBUF,
+	       rpc->regs + RPC_PHYCNT);
+
+	for (tx_offs = 0; tx_offs < RPC_WBUF_SIZE; tx_offs += 4)
+		writel(*(u32 *)(buf + tx_offs), rpc->regs + RPC_WBUF + tx_offs);
+
+	writel(rpc->cmd, rpc->regs + RPC_SMCMR);
+	writel(offs, rpc->regs + RPC_SMADR);
+	writel(rpc->smenr, rpc->regs + RPC_SMENR);
+	writel(rpc->smcr | RPC_SMCR_SPIE, rpc->regs + RPC_SMCR);
+	ret = wait_msg_xfer_end(rpc);
+	if (ret)
+		goto out;
+
+	writel(RPC_DRCR_RCF, rpc->regs + RPC_DRCR);
+	writel(RPC_PHYCNT_CAL | RPC_PHYCNT_STRTIM(0) | 0x260,
+	       rpc->regs + RPC_PHYCNT);
+
+	return len;
+out:
+	return ret;
+}
+
+static int rpc_spi_mem_dirmap_create(struct spi_mem_dirmap_desc *desc)
+{
+	struct rpc_spi *rpc = spi_master_get_devdata(desc->mem->spi->master);
+
+	if (desc->info.offset + desc->info.length > U32_MAX)
+		return -ENOTSUPP;
+
+	if (!rpc_spi_mem_supports_op(desc->mem, &desc->info.op_tmpl))
+		return -ENOTSUPP;
+
+	if (!rpc->linear.map &&
+	    desc->info.op_tmpl.data.dir == SPI_MEM_DATA_IN)
+		return -ENOTSUPP;
+
+	return 0;
+}
+
+static int rpc_spi_mem_exec_op(struct spi_mem *mem,
+			       const struct spi_mem_op *op)
+{
+	struct rpc_spi *rpc = spi_master_get_devdata(mem->spi->master);
+	int ret;
+
+	ret = rpc_spi_set_freq(rpc, mem->spi->max_speed_hz);
+	if (ret)
+		return ret;
+
+	rpc_spi_mem_set_prep_op_cfg(mem->spi, op, NULL, NULL);
+
+	ret = rpc_spi_io_xfer(rpc,
+			      op->data.dir == SPI_MEM_DATA_OUT ?
+			      op->data.buf.out : NULL,
+			      op->data.dir == SPI_MEM_DATA_IN ?
+			      op->data.buf.in : NULL);
+
+	return ret;
+}
+
+static const struct spi_controller_mem_ops rpc_spi_mem_ops = {
+	.supports_op = rpc_spi_mem_supports_op,
+	.exec_op = rpc_spi_mem_exec_op,
+	.dirmap_create = rpc_spi_mem_dirmap_create,
+	.dirmap_read = rpc_spi_mem_dirmap_read,
+	.dirmap_write = rpc_spi_mem_dirmap_write,
+};
+
+static void rpc_spi_transfer_setup(struct rpc_spi *rpc,
+				   struct spi_message *msg)
+{
+	struct spi_transfer *t, xfer[4] = { };
+	u32 i, xfercnt, xferpos = 0;
+
+	rpc->totalxferlen = 0;
+	list_for_each_entry(t, &msg->transfers, transfer_list) {
+		if (t->tx_buf) {
+			xfer[xferpos].tx_buf = t->tx_buf;
+			xfer[xferpos].tx_nbits = t->tx_nbits;
+		}
+
+		if (t->rx_buf) {
+			xfer[xferpos].rx_buf = t->rx_buf;
+			xfer[xferpos].rx_nbits = t->rx_nbits;
+		}
+
+		if (t->len) {
+			xfer[xferpos++].len = t->len;
+			rpc->totalxferlen += t->len;
+		}
+	}
+
+	xfercnt = xferpos;
+	rpc->xferlen = xfer[--xferpos].len;
+	rpc->cmd = RPC_SMCMR_CMD(((u8 *)xfer[0].tx_buf)[0]);
+	rpc->smenr = RPC_SMENR_CDE | RPC_SMENR_CDB(fls(xfer[0].tx_nbits >> 1));
+	rpc->addr = 0;
+
+	if (xfercnt > 2 && xfer[1].len && xfer[1].tx_buf) {
+		rpc->smenr |= RPC_SMENR_ADB(fls(xfer[1].tx_nbits >> 1));
+		for (i = 0; i < xfer[1].len; i++)
+			rpc->addr |= (u32)((u8 *)xfer[1].tx_buf)[i]
+					<< (8 * (xfer[1].len - i - 1));
+
+		if (xfer[1].len == 4)
+			rpc->smenr |= RPC_SMENR_ADE(0xf);
+		else
+			rpc->smenr |= RPC_SMENR_ADE(0x7);
+	}
+
+	switch (xfercnt) {
+	case 2:
+		if (xfer[1].rx_buf) {
+			rpc->smenr |= RPC_SMENR_SPIDE(rpc_bits_xfer
+				      (xfer[1].len)) | RPC_SMENR_SPIDB(fls
+				      (xfer[1].rx_nbits >> 1));
+			rpc->smcr = RPC_SMCR_SPIRE;
+			rpc->xfer_dir = SPI_MEM_DATA_IN;
+		} else if (xfer[1].tx_buf) {
+			rpc->smenr |= RPC_SMENR_SPIDE(rpc_bits_xfer
+				      (xfer[1].len)) | RPC_SMENR_SPIDB(fls
+				      (xfer[1].tx_nbits >> 1));
+			rpc->smcr = RPC_SMCR_SPIWE;
+			rpc->xfer_dir = SPI_MEM_DATA_OUT;
+		}
+		break;
+
+	case 3:
+		if (xfer[2].len && xfer[2].rx_buf && !xfer[2].tx_buf) {
+			rpc->smenr |= RPC_SMENR_SPIDE(rpc_bits_xfer
+				      (xfer[2].len)) | RPC_SMENR_SPIDB(fls
+				      (xfer[2].rx_nbits >> 1));
+			rpc->smcr = RPC_SMCR_SPIRE;
+			rpc->xfer_dir = SPI_MEM_DATA_IN;
+		} else if (xfer[2].len && xfer[2].tx_buf && !xfer[2].rx_buf) {
+			rpc->smenr |= RPC_SMENR_SPIDE(rpc_bits_xfer
+				      (xfer[2].len)) | RPC_SMENR_SPIDB(fls
+				      (xfer[2].tx_nbits >> 1));
+			rpc->smcr = RPC_SMCR_SPIWE;
+			rpc->xfer_dir = SPI_MEM_DATA_OUT;
+		}
+
+		break;
+
+	case 4:
+		if (xfer[2].len && xfer[2].tx_buf) {
+			rpc->smenr |= RPC_SMENR_DME;
+			rpc->dummy = RPC_SMDMCR_DMCYC(xfer[2].len);
+			writel(rpc->dummy, rpc->regs + RPC_SMDMCR);
+		}
+
+		if (xfer[3].len && xfer[3].rx_buf) {
+			rpc->smenr |= RPC_SMENR_SPIDE(rpc_bits_xfer
+				      (xfer[3].len)) | RPC_SMENR_SPIDB(fls
+				      (xfer[3].rx_nbits >> 1));
+			rpc->smcr = RPC_SMCR_SPIRE;
+			rpc->xfer_dir = SPI_MEM_DATA_IN;
+		}
+
+		break;
+
+	default:
+		break;
+	}
+}
+
+static int rpc_spi_xfer_message(struct rpc_spi *rpc, struct spi_transfer *t)
+{
+	int ret;
+
+	ret = rpc_spi_set_freq(rpc, t->speed_hz);
+	if (ret)
+		return ret;
+
+	ret = rpc_spi_io_xfer(rpc,
+			      rpc->xfer_dir == SPI_MEM_DATA_OUT ?
+			      t->tx_buf : NULL,
+			      rpc->xfer_dir == SPI_MEM_DATA_IN ?
+			      t->rx_buf : NULL);
+
+	return ret;
+}
+
+static int rpc_spi_transfer_one_message(struct spi_master *master,
+					struct spi_message *msg)
+{
+	struct rpc_spi *rpc = spi_master_get_devdata(master);
+	struct spi_transfer *t;
+	int ret;
+
+	rpc_spi_transfer_setup(rpc, msg);
+
+	list_for_each_entry(t, &msg->transfers, transfer_list) {
+		if (list_is_last(&t->transfer_list, &msg->transfers)) {
+			ret = rpc_spi_xfer_message(rpc, t);
+			if (ret)
+				goto out;
+		}
+	}
+
+	msg->status = 0;
+	msg->actual_length = rpc->totalxferlen;
+out:
+	spi_finalize_current_message(master);
+	return 0;
+}
+
+static int __maybe_unused rpc_spi_runtime_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct spi_master *master = platform_get_drvdata(pdev);
+	struct rpc_spi *rpc = spi_master_get_devdata(master);
+
+	clk_disable_unprepare(rpc->clk_rpc);
+
+	return 0;
+}
+
+static int __maybe_unused rpc_spi_runtime_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct spi_master *master = platform_get_drvdata(pdev);
+	struct rpc_spi *rpc = spi_master_get_devdata(master);
+	int ret;
+
+	ret = clk_prepare_enable(rpc->clk_rpc);
+	if (ret)
+		dev_err(dev, "Can't enable rpc->clk_rpc\n");
+
+	return ret;
+}
+
+static const struct dev_pm_ops rpc_spi_dev_pm_ops = {
+	SET_RUNTIME_PM_OPS(rpc_spi_runtime_suspend,
+			   rpc_spi_runtime_resume, NULL)
+};
+
+static int rpc_spi_probe(struct platform_device *pdev)
+{
+	struct spi_master *master;
+	struct resource *res;
+	struct rpc_spi *rpc;
+	int ret;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(struct rpc_spi));
+	if (!master)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, master);
+
+	rpc = spi_master_get_devdata(master);
+
+	master->dev.of_node = pdev->dev.of_node;
+
+	rpc->clk_rpc = devm_clk_get(&pdev->dev, "clk_rpc");
+	if (IS_ERR(rpc->clk_rpc))
+		return PTR_ERR(rpc->clk_rpc);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rpc_regs");
+	rpc->regs = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(rpc->regs))
+		return PTR_ERR(rpc->regs);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dirmap");
+	rpc->linear.map = devm_ioremap_resource(&pdev->dev, res);
+	if (!IS_ERR(rpc->linear.map)) {
+		rpc->linear.dma = res->start;
+		rpc->linear.size = resource_size(res);
+	} else {
+		rpc->linear.map = NULL;
+	}
+
+	pm_runtime_enable(&pdev->dev);
+	master->auto_runtime_pm = true;
+
+	master->num_chipselect = 1;
+	master->mem_ops = &rpc_spi_mem_ops;
+	master->transfer_one_message = rpc_spi_transfer_one_message;
+
+	master->bits_per_word_mask = SPI_BPW_MASK(8);
+	master->mode_bits = SPI_CPOL | SPI_CPHA |
+			SPI_RX_DUAL | SPI_TX_DUAL |
+			SPI_RX_QUAD | SPI_TX_QUAD;
+
+	rpc_spi_hw_init(rpc);
+
+	ret = spi_register_master(master);
+	if (ret) {
+		dev_err(&pdev->dev, "spi_register_master failed\n");
+		goto err_put_master;
+	}
+	return 0;
+
+err_put_master:
+	spi_master_put(master);
+	pm_runtime_disable(&pdev->dev);
+
+	return ret;
+}
+
+static int rpc_spi_remove(struct platform_device *pdev)
+{
+	struct spi_master *master = platform_get_drvdata(pdev);
+
+	pm_runtime_disable(&pdev->dev);
+	spi_unregister_master(master);
+
+	return 0;
+}
+
+static const struct of_device_id rpc_spi_of_ids[] = {
+	{ .compatible = "renesas,rpc-r8a77995", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, rpc_spi_of_ids);
+
+static struct platform_driver rpc_spi_driver = {
+	.probe = rpc_spi_probe,
+	.remove = rpc_spi_remove,
+	.driver = {
+		.name = "rpc-spi",
+		.of_match_table = rpc_spi_of_ids,
+		.pm = &rpc_spi_dev_pm_ops,
+	},
+};
+module_platform_driver(rpc_spi_driver);
+
+MODULE_AUTHOR("Mason Yang <masonccyang@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("Renesas R-Car D3 RPC SPI controller driver");
+MODULE_LICENSE("GPL v2");
-- 
1.9.1