Add a driver for Renesas R-Car Gen3 RPC-IF SPI controller.

Signed-off-by: Mason Yang <masonccy...@mxic.com.tw>
Signed-off-by: Sergei Shtylyov <sergei.shtyl...@cogentembedded.com>
---
 drivers/spi/Kconfig           |   6 +
 drivers/spi/Makefile          |   1 +
 drivers/spi/spi-renesas-rpc.c | 804 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 811 insertions(+)
 create mode 100644 drivers/spi/spi-renesas-rpc.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 9f89cb1..6ad1782 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -544,6 +544,12 @@ config SPI_RSPI
        help
          SPI driver for Renesas RSPI and QSPI blocks.
 
+config SPI_RENESAS_RPC
+       tristate "Renesas R-Car Gen3 RPC-IF controller"
+       depends on ARCH_RENESAS || COMPILE_TEST
+       help
+         SPI driver for Renesas R-Car Gen3 RPC-IF.
+
 config SPI_QCOM_QSPI
        tristate "QTI QSPI controller"
        depends on ARCH_QCOM
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index f296270..9150732 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -84,6 +84,7 @@ 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..ea12017
--- /dev/null
+++ b/drivers/spi/spi-renesas-rpc.c
@@ -0,0 +1,804 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (C) 2018 ~ 2019 Renesas Solutions Corp.
+// Copyright (C) 2018 Macronix International Co., Ltd.
+//
+// R-Car Gen3 RPC-IF SPI/QSPI/Octa driver
+//
+// Authors:
+//     Mason Yang <masonccy...@mxic.com.tw>
+//
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/log2.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi-mem.h>
+
+#include <asm/unaligned.h>
+
+#define RPC_CMNCR              0x0000  // R/W
+#define RPC_CMNCR_MD           BIT(31)
+#define RPC_CMNCR_SFDE         BIT(24) // undocumented bit but must be set
+#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) // undocumented
+#define RPC_CMNCR_IO2FV(val)   (((val) & 0x3) << 12) // undocumented
+#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_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) - 1) & 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(c)       (((c) & 0x7) << 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_DRDB(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_OPD3(o)      (((o) & 0xFF) << 24)
+#define RPC_SMOPR_OPD2(o)      (((o) & 0xFF) << 16)
+#define RPC_SMOPR_OPD1(o)      (((o) & 0xFF) << 8)
+#define RPC_SMOPR_OPD0(o)      (((o) & 0xFF) << 0)
+
+#define RPC_SMENR              0x0030  // R/W
+#define RPC_SMENR_CDB(o)       (((o) & 0x3) << 30)
+#define RPC_SMENR_OCDB(o)      (((o) & 0x3) << 28)
+#define RPC_SMENR_ADB(o)       (((o) & 0x3) << 24)
+#define RPC_SMENR_OPDB(o)      (((o) & 0x3) << 20)
+#define RPC_SMENR_SPIDB(o)     (((o) & 0x3) << 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       (0x7 << 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_PHYMEM(v)   (((v) & 0x3) << 0)
+
+#define RPC_PHYOFFSET1         0x0080  // R/W
+#define RPC_PHYOFFSET1_DDRTMG(v) (((v) & 0x3) << 28)
+#define RPC_PHYOFFSET2         0x0084  // R/W
+#define RPC_PHYOFFSET2_OCTTMG(v) (((v) & 0x7) << 8)
+
+#define RPC_WBUF_SIZE          256     // Write Buffer size
+
+struct rpc_spi {
+       struct clk *clk_rpc;
+       void __iomem *base;
+       void __iomem *dirmap;
+       void __iomem *wbuf;
+       struct regmap *regmap;
+       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;
+       struct reset_control *rstc;
+};
+
+static int rpc_spi_set_freq(struct rpc_spi *rpc, unsigned long freq)
+{
+       int ret;
+
+       if (rpc->cur_speed_hz == freq)
+               return 0;
+
+       ret = clk_set_rate(rpc->clk_rpc, freq);
+       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.
+       //      RPC_PHYCNT_STRTIM is strobe timing adjustment bit,
+       //      0x0 : the delay is biggest,
+       //      0x1 : the delay is 2nd biggest,
+       //      On H3 ES1.x, the value should be 0, while on others,
+       //      the value should be 6.
+       //
+       regmap_write(rpc->regmap, RPC_PHYCNT, RPC_PHYCNT_CAL |
+                                 RPC_PHYCNT_STRTIM(6) | 0x260);
+
+       //
+       // NOTE: The 0x1511144 are undocumented bits, but they must be set
+       //       for RPC_PHYOFFSET1.
+       //       The 0x31 are undocumented bits, but they must be set
+       //       for RPC_PHYOFFSET2.
+       //
+       regmap_write(rpc->regmap, RPC_PHYOFFSET1, RPC_PHYOFFSET1_DDRTMG(3) |
+                    0x1511144);
+       regmap_write(rpc->regmap, RPC_PHYOFFSET2, 0x31 |
+                    RPC_PHYOFFSET2_OCTTMG(4));
+       regmap_write(rpc->regmap, RPC_SSLDR, RPC_SSLDR_SPNDL(7) |
+                    RPC_SSLDR_SLNDL(7) | RPC_SSLDR_SCKDL(7));
+       regmap_write(rpc->regmap, RPC_CMNCR, RPC_CMNCR_MD | RPC_CMNCR_SFDE |
+                    RPC_CMNCR_MOIIO_HIZ | RPC_CMNCR_IOFV_HIZ |
+                    RPC_CMNCR_BSZ(0));
+}
+
+static int wait_msg_xfer_end(struct rpc_spi *rpc)
+{
+       u32 sts;
+
+       return regmap_read_poll_timeout(rpc->regmap, RPC_CMNSR, sts,
+                                       sts & RPC_CMNSR_TEND, 0, USEC_PER_SEC);
+}
+
+static u8 rpc_bits_set(u32 nbytes)
+{
+       nbytes = clamp(nbytes, 1U, 4U);
+
+       return GENMASK(3, 4 - nbytes);
+}
+
+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;
+
+       regmap_update_bits(rpc->regmap, RPC_CMNCR, RPC_CMNCR_MD, RPC_CMNCR_MD);
+       regmap_write(rpc->regmap, RPC_SMDRENR, 0);
+       regmap_write(rpc->regmap, RPC_SMCMR, rpc->cmd);
+       regmap_write(rpc->regmap, RPC_SMDMCR, rpc->dummy);
+       regmap_write(rpc->regmap, RPC_SMADR, rpc->addr);
+       smenr = rpc->smenr;
+
+       if (tx_buf) {
+               while (pos < rpc->xferlen) {
+                       u32 nbytes = rpc->xferlen - pos;
+
+                       regmap_write(rpc->regmap, RPC_SMWDR0,
+                                    get_unaligned((u32 *)(tx_buf + pos)));
+
+                       smcr = rpc->smcr | RPC_SMCR_SPIE;
+
+                       if (nbytes > 4) {
+                               nbytes = 4;
+                               smcr |= RPC_SMCR_SSLKP;
+                       }
+
+                       regmap_write(rpc->regmap, RPC_SMENR, smenr);
+                       regmap_write(rpc->regmap, RPC_SMCR, smcr);
+                       ret = wait_msg_xfer_end(rpc);
+                       if (ret)
+                               goto err_out;
+
+                       pos += nbytes;
+                       smenr = rpc->smenr & ~RPC_SMENR_CDE &
+                                            ~RPC_SMENR_ADE(0xf);
+               }
+       } else if (rx_buf) {
+               //
+               // RPC-IF spoils the data for the commands without an address
+               // phase (like RDID) in the manual mode, so we'll have to work
+               // around this issue by using the external address space read
+               // mode instead.
+               //
+               if (!(smenr & RPC_SMENR_ADE(0xf))) {
+                       regmap_update_bits(rpc->regmap, RPC_CMNCR,
+                                          RPC_CMNCR_MD, 0);
+                       regmap_write(rpc->regmap, RPC_DRCR,
+                                    RPC_DRCR_RBURST(32) | RPC_DRCR_RBE);
+                       regmap_write(rpc->regmap, RPC_DREAR, RPC_DREAR_EAC(1));
+                       regmap_write(rpc->regmap, RPC_DRCMR, rpc->cmd);
+                       regmap_write(rpc->regmap, RPC_DRDMCR, rpc->dummy);
+                       regmap_write(rpc->regmap, RPC_DROPR, 0);
+                       regmap_write(rpc->regmap, RPC_DRENR, smenr);
+                       memcpy_fromio(rx_buf, rpc->dirmap, rpc->xferlen);
+                       regmap_write(rpc->regmap, RPC_DRCR, RPC_DRCR_RCF);
+               } else {
+                       while (pos < rpc->xferlen) {
+                               u32 nbytes = rpc->xferlen - pos;
+
+                               if (nbytes > 4)
+                                       nbytes = 4;
+
+                               regmap_write(rpc->regmap, RPC_SMENR, smenr);
+                               regmap_write(rpc->regmap, RPC_SMCR, rpc->smcr |
+                                            RPC_SMCR_SPIE);
+                               ret = wait_msg_xfer_end(rpc);
+                               if (ret)
+                                       goto err_out;
+
+                               regmap_read(rpc->regmap, RPC_SMRDR0, &data);
+                               memcpy(rx_buf + pos, &data, nbytes);
+                               pos += nbytes;
+
+                               regmap_write(rpc->regmap, RPC_SMADR,
+                                            rpc->addr + pos);
+                       }
+               }
+       } else {
+               regmap_write(rpc->regmap, RPC_SMENR, rpc->smenr);
+               regmap_write(rpc->regmap, RPC_SMCR, rpc->smcr | RPC_SMCR_SPIE);
+               ret = wait_msg_xfer_end(rpc);
+               if (ret)
+                       goto err_out;
+       }
+
+       return 0;
+
+err_out:
+       return reset_control_reset(rpc->rstc);
+}
+
+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_controller_get_devdata(spi->controller);
+
+       rpc->cmd = RPC_SMCMR_CMD(op->cmd.opcode);
+       rpc->smenr = RPC_SMENR_CDE |
+                    RPC_SMENR_CDB(ilog2(op->cmd.buswidth));
+       rpc->totalxferlen = 1;
+       rpc->xfer_dir = SPI_MEM_NO_DATA;
+       rpc->xferlen = 0;
+       rpc->addr = 0;
+
+       if (op->addr.nbytes) {
+               rpc->smenr |= RPC_SMENR_ADB(ilog2(op->addr.buswidth));
+               if (op->addr.nbytes == 4)
+                       rpc->smenr |= RPC_SMENR_ADE(0xf);
+               else
+                       rpc->smenr |= RPC_SMENR_ADE(0x7);
+
+               if (offs && len)
+                       rpc->addr = *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)) {
+               switch (op->data.dir) {
+               case SPI_MEM_DATA_IN:
+                       rpc->smcr = RPC_SMCR_SPIRE;
+                       rpc->xfer_dir = SPI_MEM_DATA_IN;
+                       break;
+               case SPI_MEM_DATA_OUT:
+                       rpc->smcr = RPC_SMCR_SPIWE;
+                       rpc->xfer_dir = SPI_MEM_DATA_OUT;
+                       break;
+               default:
+                       break;
+               }
+
+               if (offs && len) {
+                       rpc->smenr |= RPC_SMENR_SPIDE(rpc_bits_set(*len)) |
+                                     RPC_SMENR_SPIDB(ilog2(op->data.buswidth));
+                       rpc->xferlen = *len;
+                       rpc->totalxferlen += *len;
+               } else {
+                       rpc->smenr |=
+                               RPC_SMENR_SPIDE(rpc_bits_set(op->data.nbytes)) |
+                               RPC_SMENR_SPIDB(ilog2(op->data.buswidth));
+                       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 ||
+           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_controller_get_devdata(desc->mem->spi->controller);
+       int ret;
+
+       if (offs + desc->info.offset + len > U32_MAX)
+               return -EINVAL;
+
+       if (len > 0x4000000)
+               len = 0x4000000;
+
+       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);
+
+       regmap_update_bits(rpc->regmap, RPC_CMNCR, RPC_CMNCR_MD, 0);
+       regmap_write(rpc->regmap, RPC_DRCR, RPC_DRCR_RBURST(32) |
+                    RPC_DRCR_RBE);
+
+       regmap_write(rpc->regmap, RPC_DRCMR, rpc->cmd);
+       regmap_write(rpc->regmap, RPC_DREAR, RPC_DREAR_EAC(1));
+       regmap_write(rpc->regmap, RPC_DROPR, 0);
+       regmap_write(rpc->regmap, RPC_DRENR, rpc->smenr);
+       regmap_write(rpc->regmap, RPC_DRDMCR, rpc->dummy);
+       regmap_write(rpc->regmap, RPC_DRDRENR, 0);
+
+       memcpy_fromio(buf, rpc->dirmap + 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_controller_get_devdata(desc->mem->spi->controller);
+       int ret;
+
+       if (offs + desc->info.offset + len > U32_MAX)
+               return -EINVAL;
+
+       if (len > RPC_WBUF_SIZE)
+               len = RPC_WBUF_SIZE;
+
+       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);
+
+       regmap_update_bits(rpc->regmap, RPC_CMNCR, RPC_CMNCR_MD, RPC_CMNCR_MD);
+
+       regmap_write(rpc->regmap, RPC_SMDRENR, 0);
+
+       regmap_update_bits(rpc->regmap, RPC_PHYCNT, RPC_PHYCNT_STRTIM(7) |
+                          RPC_PHYCNT_WBUF2 | RPC_PHYCNT_WBUF,
+                          RPC_PHYCNT_WBUF2 | RPC_PHYCNT_WBUF);
+
+       memcpy_toio(rpc->wbuf, buf, len);
+
+       regmap_write(rpc->regmap, RPC_SMCMR, rpc->cmd);
+       regmap_write(rpc->regmap, RPC_SMADR, offs);
+       regmap_write(rpc->regmap, RPC_SMENR, rpc->smenr);
+       regmap_write(rpc->regmap, RPC_SMCR, rpc->smcr | RPC_SMCR_SPIE);
+       ret = wait_msg_xfer_end(rpc);
+       if (ret)
+               goto err_out;
+
+       regmap_write(rpc->regmap, RPC_DRCR, RPC_DRCR_RCF);
+
+       regmap_update_bits(rpc->regmap, RPC_PHYCNT, RPC_PHYCNT_STRTIM(7) |
+                          RPC_PHYCNT_WBUF2 | RPC_PHYCNT_WBUF,
+                          RPC_PHYCNT_STRTIM(6));
+
+       return len;
+
+err_out:
+       return reset_control_reset(rpc->rstc);
+}
+
+static int rpc_spi_mem_dirmap_create(struct spi_mem_dirmap_desc *desc)
+{
+       struct rpc_spi *rpc =
+                       spi_controller_get_devdata(desc->mem->spi->controller);
+
+       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->dirmap &&
+           desc->info.op_tmpl.data.dir == SPI_MEM_DATA_IN)
+               return -ENOTSUPP;
+
+       if (!rpc->wbuf &&
+           desc->info.op_tmpl.data.dir == SPI_MEM_DATA_OUT)
+               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_controller_get_devdata(mem->spi->controller);
+       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;
+       rpc->xfer_dir = SPI_MEM_NO_DATA;
+
+       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;
+               }
+
+               if (list_is_last(&t->transfer_list, &msg->transfers)) {
+                       if (xferpos > 1) {
+                               if (t->rx_buf) {
+                                       rpc->xfer_dir = SPI_MEM_DATA_IN;
+                                       rpc->smcr = RPC_SMCR_SPIRE;
+                               } else if (t->tx_buf) {
+                                       rpc->xfer_dir = SPI_MEM_DATA_OUT;
+                                       rpc->smcr = RPC_SMCR_SPIWE;
+                               }
+                       }
+               }
+       }
+
+       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(ilog2((unsigned int)xfer[0].tx_nbits));
+       rpc->addr = 0;
+
+       if (xfercnt > 2 && xfer[1].len && xfer[1].tx_buf) {
+               rpc->smenr |=
+                       RPC_SMENR_ADB(ilog2((unsigned int)xfer[1].tx_nbits));
+
+               for (i = 0; i < xfer[1].len; i++)
+                       rpc->addr |= ((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);
+       }
+
+       if (xfercnt > 3 && xfer[2].len && xfer[2].tx_buf) {
+               rpc->smenr |= RPC_SMENR_DME;
+               rpc->dummy = RPC_SMDMCR_DMCYC(xfer[2].len);
+       }
+
+       for (i = xfercnt - 1; i < xfercnt && xfercnt > 1; i++) {
+               if (xfer[i].rx_buf) {
+                       rpc->smenr |=
+                               RPC_SMENR_SPIDE(rpc_bits_set(xfer[i].len)) |
+                               RPC_SMENR_SPIDB(ilog2
+                                       ((unsigned int)xfer[i].rx_nbits));
+               } else if (xfer[i].tx_buf) {
+                       rpc->smenr |=
+                               RPC_SMENR_SPIDE(rpc_bits_set(xfer[i].len)) |
+                               RPC_SMENR_SPIDB(ilog2
+                                       ((unsigned int)xfer[i].tx_nbits));
+               }
+       }
+}
+
+static inline int rpc_spi_xfer_message(struct rpc_spi *rpc,
+                                      struct spi_transfer *data_xfer)
+{
+       int ret;
+
+       ret = rpc_spi_set_freq(rpc, data_xfer->speed_hz);
+       if (ret)
+               return ret;
+
+       ret = rpc_spi_io_xfer(rpc,
+                             rpc->xfer_dir == SPI_MEM_DATA_OUT ?
+                             data_xfer->tx_buf : NULL,
+                             rpc->xfer_dir == SPI_MEM_DATA_IN ?
+                             data_xfer->rx_buf : NULL);
+
+       return ret;
+}
+
+static int rpc_spi_transfer_one_message(struct spi_controller *ctlr,
+                                       struct spi_message *msg)
+{
+       struct rpc_spi *rpc = spi_controller_get_devdata(ctlr);
+       struct spi_transfer *data_xfer;
+       int ret;
+
+       rpc_spi_transfer_setup(rpc, msg);
+
+       data_xfer = list_last_entry(&msg->transfers, struct spi_transfer,
+                                   transfer_list);
+
+       ret = rpc_spi_xfer_message(rpc, data_xfer);
+       if (ret)
+               goto out;
+
+       msg->status = 0;
+       msg->actual_length = rpc->totalxferlen;
+out:
+       spi_finalize_current_message(ctlr);
+       return 0;
+}
+
+static const struct regmap_range rpc_spi_volatile_ranges[] = {
+       regmap_reg_range(RPC_SMRDR0, RPC_SMRDR0),
+       regmap_reg_range(RPC_SMWDR0, RPC_SMWDR0),
+       regmap_reg_range(RPC_CMNSR, RPC_CMNSR),
+};
+
+static const struct regmap_access_table rpc_spi_volatile_table = {
+       .yes_ranges     = rpc_spi_volatile_ranges,
+       .n_yes_ranges   = ARRAY_SIZE(rpc_spi_volatile_ranges),
+};
+
+static const struct regmap_config rpc_spi_regmap_config = {
+       .reg_bits = 32,
+       .val_bits = 32,
+       .reg_stride = 4,
+       .fast_io = true,
+       .max_register = RPC_PHYOFFSET2,
+       .volatile_table = &rpc_spi_volatile_table,
+};
+
+static int rpc_spi_probe(struct platform_device *pdev)
+{
+       struct spi_controller *ctlr;
+       struct resource *res;
+       struct rpc_spi *rpc;
+       struct device_node *flash;
+       int ret;
+
+       flash = of_get_next_child(pdev->dev.of_node, NULL);
+       if (!flash) {
+               dev_warn(&pdev->dev, "no flash node found\n");
+               return -ENODEV;
+       }
+
+       ret = of_device_is_compatible(flash, "jedec,spi-nor");
+       if (!ret) {
+               dev_warn(&pdev->dev, "no spi-nor device found\n");
+               return -ENODEV;
+       }
+
+       ctlr = spi_alloc_master(&pdev->dev, sizeof(*rpc));
+       if (!ctlr)
+               return -ENOMEM;
+
+       platform_set_drvdata(pdev, ctlr);
+
+       rpc = spi_controller_get_devdata(ctlr);
+
+       ctlr->dev.of_node = pdev->dev.of_node;
+
+       rpc->clk_rpc = devm_clk_get(&pdev->dev, "rpc");
+       if (IS_ERR(rpc->clk_rpc))
+               return PTR_ERR(rpc->clk_rpc);
+
+       res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
+       rpc->base = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(rpc->base))
+               return PTR_ERR(rpc->base);
+
+       rpc->regmap = devm_regmap_init_mmio(&pdev->dev, rpc->base,
+                                           &rpc_spi_regmap_config);
+       if (IS_ERR(rpc->regmap)) {
+               dev_err(&pdev->dev,
+                       "failed to init regmap for rpc-spi, error %ld\n",
+                       PTR_ERR(rpc->regmap));
+               return PTR_ERR(rpc->regmap);
+       }
+
+       res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dirmap");
+       rpc->dirmap = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(rpc->dirmap))
+               rpc->dirmap = NULL;
+
+       res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "wbuf");
+       rpc->wbuf = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(rpc->wbuf))
+               rpc->wbuf = NULL;
+
+       rpc->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+       if (IS_ERR(rpc->rstc))
+               return PTR_ERR(rpc->rstc);
+
+       pm_runtime_enable(&pdev->dev);
+       ctlr->auto_runtime_pm = true;
+
+       ctlr->num_chipselect = 1;
+       ctlr->mem_ops = &rpc_spi_mem_ops;
+       ctlr->transfer_one_message = rpc_spi_transfer_one_message;
+
+       ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
+       ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_TX_QUAD | SPI_RX_QUAD;
+
+       rpc_spi_hw_init(rpc);
+
+       ret = spi_register_controller(ctlr);
+       if (ret) {
+               dev_err(&pdev->dev, "spi_register_controller failed\n");
+               goto err_put_ctlr;
+       }
+       return 0;
+
+err_put_ctlr:
+       spi_controller_put(ctlr);
+       pm_runtime_disable(&pdev->dev);
+
+       return ret;
+}
+
+static int rpc_spi_remove(struct platform_device *pdev)
+{
+       struct spi_controller *ctlr = platform_get_drvdata(pdev);
+
+       pm_runtime_disable(&pdev->dev);
+       spi_unregister_controller(ctlr);
+
+       return 0;
+}
+
+static const struct of_device_id rpc_spi_of_ids[] = {
+       { .compatible = "renesas,rcar-gen3-rpc", },
+       { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, rpc_spi_of_ids);
+
+#ifdef CONFIG_PM_SLEEP
+static int rpc_spi_suspend(struct device *dev)
+{
+       struct spi_controller *ctlr = dev_get_drvdata(dev);
+
+       return spi_controller_suspend(ctlr);
+}
+
+static int rpc_spi_resume(struct device *dev)
+{
+       struct spi_controller *ctlr = dev_get_drvdata(dev);
+
+       return spi_controller_resume(ctlr);
+}
+
+static SIMPLE_DEV_PM_OPS(rpc_spi_pm_ops, rpc_spi_suspend, rpc_spi_resume);
+#define DEV_PM_OPS     (&rpc_spi_pm_ops)
+#else
+#define DEV_PM_OPS     NULL
+#endif
+
+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 = DEV_PM_OPS,
+       },
+};
+module_platform_driver(rpc_spi_driver);
+
+MODULE_AUTHOR("Mason Yang <masonccy...@mxic.com.tw>");
+MODULE_DESCRIPTION("Renesas R-Car Gen3 RPC-IF SPI controller driver");
+MODULE_LICENSE("GPL v2");
-- 
1.9.1

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