Add a driver for the SPIBSC controller in Renesas SoC devices.
Signed-off-by: Chris Brandt <chris.brandt@xxxxxxxxxxx>
---
drivers/spi/Kconfig | 8 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-spibsc.c | 609 +++++++++++++++++++++++++++++++++++++++
3 files changed, 618 insertions(+)
create mode 100644 drivers/spi/spi-spibsc.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 870f7797b56b..405d7e73963e 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -575,6 +575,14 @@ config SPI_RSPI
help
SPI driver for Renesas RSPI and QSPI blocks.
+config SPI_SPIBSC
+ tristate "Renesas SPI Multi I/O Bus Controller"
+ depends on ARCH_R7S72100 || ARCH_R7S9210
+ help
+ Also referred to as the SPI Bus Space Controller (SPIBSC).
+ This controller was designed specifically for accessing QSPI flash
+ devices.
+
config SPI_QCOM_QSPI
tristate "QTI QSPI controller"
depends on ARCH_QCOM
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index bb49c9e6d0a0..9525256c4d51 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -99,6 +99,7 @@ obj-$(CONFIG_SPI_SH_SCI) += spi-sh-sci.o
obj-$(CONFIG_SPI_SIFIVE) += spi-sifive.o
obj-$(CONFIG_SPI_SIRF) += spi-sirf.o
obj-$(CONFIG_SPI_SLAVE_MT27XX) += spi-slave-mt27xx.o
+obj-$(CONFIG_SPI_SPIBSC) += spi-spibsc.o
obj-$(CONFIG_SPI_SPRD) += spi-sprd.o
obj-$(CONFIG_SPI_SPRD_ADI) += spi-sprd-adi.o
obj-$(CONFIG_SPI_STM32) += spi-stm32.o
diff --git a/drivers/spi/spi-spibsc.c b/drivers/spi/spi-spibsc.c
new file mode 100644
index 000000000000..ac7e6c84417c
--- /dev/null
+++ b/drivers/spi/spi-spibsc.c
@@ -0,0 +1,609 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SPI Bus Space Controller (SPIBSC) bus driver
+ * Otherwise known as a SPI Multi I/O Bus Controller
+ *
+ * Copyright (C) 2019 Renesas Electronics
+ *
+ */
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/clk.h>
+#include <linux/pm_runtime.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/spi/spi.h>
+
+/* SPIBSC registers */
+#define CMNCR 0x00
+#define SSLDR 0x04
+#define SPBCR 0x08
+#define DRCR 0x0c
+#define DRCMR 0x10
+#define DREAR 0x14
+#define DROPR 0x18
+#define DRENR 0x1c
+#define SMCR 0x20
+#define SMCMR 0x24
+#define SMADR 0x28
+#define SMOPR 0x2c
+#define SMENR 0x30
+#define SMRDR0 0x38
+#define SMRDR1 0x3c
+#define SMWDR0 0x40
+#define SMWDR1 0x44
+#define CMNSR 0x48
+#define SMDMCR 0x60
+#define SMDRENR 0x64
+
+/* CMNCR */
+#define CMNCR_MD BIT(31)
+#define CMNCR_SFDE BIT(24)
+#define CMNCR_MOIIO3(x) (((u32)(x) & 0x3) << 22)
+#define CMNCR_MOIIO2(x) (((u32)(x) & 0x3) << 20)
+#define CMNCR_MOIIO1(x) (((u32)(x) & 0x3) << 18)
+#define CMNCR_MOIIO0(x) (((u32)(x) & 0x3) << 16)
+#define CMNCR_IO3FV(x) (((u32)(x) & 0x3) << 14)
+#define CMNCR_IO2FV(x) (((u32)(x) & 0x3) << 12)
+#define CMNCR_IO0FV(x) (((u32)(x) & 0x3) << 8)
+#define CMNCR_CPHAT BIT(6)
+#define CMNCR_CPHAR BIT(5)
+#define CMNCR_SSLP BIT(4)
+#define CMNCR_CPOL BIT(3)
+#define CMNCR_BSZ(n) (((u32)(n) & 0x3) << 0)
+#define OUT_0 (0u)
+#define OUT_1 (1u)
+#define OUT_REV (2u)
+#define OUT_HIZ (3u)
+#define BSZ_SINGLE (0)
+#define BSZ_DUAL (1)
+#define CMNCR_INIT (CMNCR_MD | \
+ CMNCR_SFDE | \
+ CMNCR_MOIIO3(OUT_HIZ) | \
+ CMNCR_MOIIO2(OUT_HIZ) | \
+ CMNCR_MOIIO1(OUT_HIZ) | \
+ CMNCR_MOIIO0(OUT_HIZ) | \
+ CMNCR_IO3FV(OUT_HIZ) | \
+ CMNCR_IO2FV(OUT_HIZ) | \
+ CMNCR_IO0FV(OUT_HIZ) | \
+ CMNCR_CPHAR | \
+ CMNCR_BSZ(BSZ_SINGLE))
+
+/* SSLDR */
+#define SSLDR_SPNDL(x) (((u32)(x) & 0x7) << 16)
+#define SSLDR_SLNDL(x) (((u32)(x) & 0x7) << 8)
+#define SSLDR_SCKDL(x) (((u32)(x) & 0x7) << 0)
+#define SSLDR_INIT (SSLDR_SPNDL(3) | SSLDR_SLNDL(3) | SSLDR_SCKDL(3))
+
+/* SPBCR */
+#define SPBCR_SPBR(x) (((u32)(x) & 0xff) << 8)
+#define SPBCR_BRDV(x) (((u32)(x) & 0x3) << 0)
+
+/* DRCR (read mode) */
+#define DRCR_SSLN BIT(24)
+#define DRCR_RBURST(x) (((u32)(x) & 0xf) << 16)
+#define DRCR_RCF BIT(9)
+#define DRCR_RBE BIT(8)
+#define DRCR_SSLE BIT(0)
+
+/* DROPR (read mode) */
+#define DROPR_OPD3(o) (((u32)(o) & 0xff) << 24)
+#define DROPR_OPD2(o) (((u32)(o) & 0xff) << 16)
+#define DROPR_OPD1(o) (((u32)(o) & 0xff) << 8)
+#define DROPR_OPD0(o) (((u32)(o) & 0xff) << 0)
+
+/* DRENR (read mode) */
+#define DRENR_CDE BIT(14)
+#define DRENR_OCDE BIT(12)
+#define DRENR_OPDE(o) (((u32)(o) & 0xf) << 4)
+
+/* SMCR (spi mode) */
+#define SMCR_SSLKP BIT(8)
+#define SMCR_SPIRE BIT(2)
+#define SMCR_SPIWE BIT(1)
+#define SMCR_SPIE BIT(0)
+
+/* SMCMR (spi mode) */
+#define SMCMR_CMD(c) (((u32)(c) & 0xff) << 16)
+#define SMCMR_OCMD(o) (((u32)(o) & 0xff) << 0)
+
+/* SMENR (spi mode) */
+#define SMENR_SPIDE(b) (((u32)(b) & 0xf) << 0)
+#define SPIDE_8BITS (0x8)
+#define SPIDE_16BITS (0xc)
+#define SPIDE_32BITS (0xf)
+
+/* CMNSR (spi mode) */
+#define CMNSR_SSLF BIT(1)
+#define CMNSR_TEND BIT(0)
+
+#define MAX_CMD_LEN 6
+
+/* HW Option Flags */
+#define HAS_SPBCR BIT(0)
+
+struct spibsc_priv {
+ void __iomem *base; /* register base */
+ void __iomem *mmio; /* memory mapped io space of SPI Flash */
+ int mmio_size;
+ struct spi_controller *master;
+ struct device *dev;
+ struct clk *clk;
+ u8 last_xfer;
+ u32 flags;
+};
+
+static void spibsc_write(struct spibsc_priv *sbsc, int reg, u32 val)
+{
+ iowrite32(val, sbsc->base + reg);
+}
+static void spibsc_write8(struct spibsc_priv *sbsc, int reg, u8 val)
+{
+ iowrite8(val, sbsc->base + reg);
+}
+static void spibsc_write16(struct spibsc_priv *sbsc, int reg, u16 val)
+{
+ iowrite16(val, sbsc->base + reg);
+}
+static u32 spibsc_read(struct spibsc_priv *sbsc, int reg)
+{
+ return ioread32(sbsc->base + reg);
+}
+
+static void spibsc_print_data(struct spibsc_priv *sbsc, u8 tx, const u8 *buf,
+ int len)
+{
+#if defined(DEBUG_PRINT_DATA)
+ char line_buffer[3*16+1];
+ int i, line_index = 0;
+
+ if (tx)
+ pr_debug("spibsc: send data: ");
+ else
+ pr_debug("spibsc: recv data: ");
+
+ for (i = 0; i < len; ) {
+ sprintf(line_buffer + line_index, " %02X", buf[i]);
+ line_index += 3;
+ i++;
+ if (i % 16 == 0) {
+ pr_debug(line_buffer);
+ line_index = 0;
+ }
+ }
+ if (i % 16 != 0)
+ pr_debug(line_buffer);
+ else
+ pr_debug("\n");
+#endif
+}
+
+static int spibsc_wait_trans_completion(struct spibsc_priv *sbsc)
+{
+ int t = 256 * 100000;
+
+ while (t--) {
+ if (spibsc_read(sbsc, CMNSR) & CMNSR_TEND)
+ return 0;
+ ndelay(1);
+ }
+
+ dev_err(sbsc->dev, "Timeout waiting for TEND\n");
+ return -ETIMEDOUT;
+}
+
+/*
+ * This function sends data using 'SPI operation mode'. It is intended to be
+ * used only with SPI Flash commands that do not require any reading back from
+ * the SPI flash.
+ */
+static int spibsc_send_data(struct spibsc_priv *sbsc, const u8 *data, int len)
+{
+ u32 smcr, smenr, smwdr0;
+ int ret, unit, sslkp;
+
+ /* print data (for debugging) */
+ spibsc_print_data(sbsc, 1, data, len);
+
+ while (len > 0) {
+ if (len >= 4) {
+ unit = 4;
+ smenr = SMENR_SPIDE(SPIDE_32BITS);
+ } else {
+ unit = len;
+ if (unit == 3)
+ unit = 2;
+
+ if (unit >= 2)
+ smenr = SMENR_SPIDE(SPIDE_16BITS);
+ else
+ smenr = SMENR_SPIDE(SPIDE_8BITS);
+ }
+
+ /* set 4bytes data, bit stream */
+ smwdr0 = *data++;
+ if (unit >= 2)
+ smwdr0 |= (u32)(*data++ << 8);
+ if (unit >= 3)
+ smwdr0 |= (u32)(*data++ << 16);
+ if (unit >= 4)
+ smwdr0 |= (u32)(*data++ << 24);
+
+ /* mask unwrite area */
+ if (unit == 3)
+ smwdr0 |= 0xFF000000;
+ else if (unit == 2)
+ smwdr0 |= 0xFFFF0000;
+ else if (unit == 1)
+ smwdr0 |= 0xFFFFFF00;
+
+ /* write send data. */
+ if (unit == 2)
+ spibsc_write16(sbsc, SMWDR0, (u16)smwdr0);
+ else if (unit == 1)
+ spibsc_write8(sbsc, SMWDR0, (u8)smwdr0);
+ else
+ spibsc_write(sbsc, SMWDR0, smwdr0);
+
+ len -= unit;
+ if ((len <= 0) && sbsc->last_xfer)
+ sslkp = 0;
+ else
+ sslkp = 1;
+
+ /* set params */
+ spibsc_write(sbsc, SMCMR, 0);
+ spibsc_write(sbsc, SMADR, 0);
+ spibsc_write(sbsc, SMOPR, 0);
+ spibsc_write(sbsc, SMENR, smenr);
+
+ /* start spi transfer */
+ smcr = SMCR_SPIE|SMCR_SPIWE;
+ if (sslkp)
+ smcr |= SMCR_SSLKP;
+ spibsc_write(sbsc, SMCR, smcr);
+
+ ret = spibsc_wait_trans_completion(sbsc);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+/*
+ * This function uses 'Data Read' mode to send the command (and address) then
+ * read data back out.
+ * The HW was designed such that you program the registers with the command,
+ * base address, additional command data, etc... But, that makes things too
+ * difficult because it means this driver has to pick out those parameters from
+ * the data stream that was passed.
+ * Instead, we will ignore how the HW was 'supposed' to be used and just
+ * blindly put the Tx data (commands) to send in the registers in the order
+ * in which we know they will be transmitted:
+ *
+ * [DRCMR.CMD]+[DRCMR.OCMD]+[DROPR.OPD3]+[DROPR.OPD2]+[DROPR.OPD1]+[DROPR.OPD0]
+ *
+ * We can send up to 6 bytes this way.
+ * We will tell the HW to skip sending the 'address' because we are secretly
+ * including it in the "command" and that way we can leave the address registers
+ * blank.
+ *
+ * Note that when reading data, the HW will read in 8-byte units which usually
+ * is not an issue for SPI Flash devices.
+ */
+static int spibsc_send_recv_data(struct spibsc_priv *sbsc, u8 *tx_data,
+ int tx_len, u8 *rx_data, int rx_len)
+{
+ u32 drcmr, drenr, dropr;
+ u8 opde;
+
+ dev_dbg(sbsc->dev, "%s (tx=%d, rx=%d)\n", __func__, tx_len, rx_len);
+
+ if (tx_len > MAX_CMD_LEN) {
+ dev_err(sbsc->dev, "Command length too long (%d)", tx_len);
+ return -EIO;
+ }
+
+ if (rx_len > sbsc->mmio_size) {
+ dev_err(sbsc->dev, "Receive length too long (%d)", rx_len);
+ return -EIO;
+ }
+
+ /* Setup Data Read mode
+ * Flush read cache and enable burst mode. Burst mode is required
+ * in order to keep chip select low between read transfers, but it
+ * also means data is read in 8-byte intervals.
+ */
+ spibsc_write(sbsc, DRCR, DRCR_SSLN | DRCR_RCF | DRCR_RBE | DRCR_SSLE);
+ spibsc_read(sbsc, DRCR);
+
+ /* Enter Data Read mode */
+ spibsc_write(sbsc, CMNCR, 0x01FFF300);
+ drcmr = 0;
+ drenr = 0;
+ dropr = 0;
+ opde = 0;
+
+ if (tx_len >= 1) {
+ /* Use 'Command' register for the 1st byte */
+ drcmr |= SMCMR_CMD(tx_data[0]);
+ drenr |= DRENR_CDE;
+ }
+
+ if (tx_len >= 2) {
+ /* Use 'Optional Command' register for the 2nd byte */
+ drcmr |= SMCMR_OCMD(tx_data[1]);
+ drenr |= DRENR_OCDE;
+ }
+
+ /* Use 'Option Data' for 3rd-6th bytes */
+ switch (tx_len) {
+ case 6:
+ dropr |= DROPR_OPD0(tx_data[5]);
+ opde |= (1 << 0);
+ case 5:
+ dropr |= DROPR_OPD1(tx_data[4]);
+ opde |= (1 << 1);
+ case 4:
+ dropr |= DROPR_OPD2(tx_data[3]);
+ opde |= (1 << 2);
+ case 3:
+ dropr |= DROPR_OPD3(tx_data[2]);
+ opde |= (1 << 3);
+ drenr |= DRENR_OPDE(opde);
+ }
+
+ spibsc_write(sbsc, DRCMR, drcmr);
+ spibsc_write(sbsc, DROPR, dropr);
+ spibsc_write(sbsc, DRENR, drenr);
+
+ /* This internal bus access is what will trigger the actual Tx/Rx
+ * operation. Remember, we don't care about the address.
+ */
+ memcpy(rx_data, sbsc->mmio, rx_len);
+
+ /* Deactivate chip select */
+ spibsc_write(sbsc, DRCR, DRCR_SSLN);
+
+ /* Print data (for debugging) */
+ spibsc_print_data(sbsc, 1, tx_data, tx_len);
+ spibsc_print_data(sbsc, 0, rx_data, rx_len);
+
+ return 0;
+}
+
+static int spibsc_transfer_one_message(struct spi_controller *master,
+ struct spi_message *msg)
+{
+ struct spibsc_priv *sbsc = spi_controller_get_devdata(master);
+ struct spi_transfer *t, *t_last;
+ u8 tx_data[MAX_CMD_LEN];
+ int tx_only;
+ u8 tx_len;
+ int ret;
+
+ t_last = list_last_entry(&msg->transfers, struct spi_transfer,
+ transfer_list);
+ /* defaults */
+ ret = 0;
+ sbsc->last_xfer = 0;
+ tx_only = 1;
+
+ /* Analyze the messages */
+ t = list_first_entry(&msg->transfers, struct spi_transfer,
+ transfer_list);
+ if (t->rx_buf) {
+ dev_dbg(sbsc->dev, "Cannot Rx without Tx first!\n");
+ return -EIO;
+ }
+ list_for_each_entry(t, &msg->transfers, transfer_list) {
+ if (t->rx_buf) {
+ tx_only = 0;
+ if (t != t_last) {
+ dev_dbg(sbsc->dev, "RX transaction is not the last transaction!\n");
+ return -EIO;
+ }
+ }
+ if (t->cs_change) {
+ dev_err(sbsc->dev, "cs_change not supported");
+ return -EIO;
+ }
+ }
+
+ /* Tx Only (SPI Mode is used) */
+ if (tx_only == 1) {
+
+ dev_dbg(sbsc->dev, "%s: TX only\n", __func__);
+
+ /* Initialize for SPI Mode */
+ spibsc_write(sbsc, CMNCR, CMNCR_INIT);
+
+ /* Send messages */
+ list_for_each_entry(t, &msg->transfers, transfer_list) {
+
+ if (t == t_last)
+ sbsc->last_xfer = 1;
+
+ ret = spibsc_send_data(sbsc, t->tx_buf, t->len);
+ if (ret)
+ break;
+
+ msg->actual_length += t->len;
+ }
+
+ /* Done */
+ msg->status = ret;
+ spi_finalize_current_message(master);
+ return ret;
+ }
+
+ /* Tx, then RX (Data Read Mode is used) */
+ dev_dbg(sbsc->dev, "%s: Tx then Rx\n", __func__);
+
+ /* Buffer up the transmit portion (cmd + addr) so we can send it all at
+ * once
+ */
+ tx_len = 0;
+ list_for_each_entry(t, &msg->transfers, transfer_list) {
+ if (t->tx_buf) {
+ if ((tx_len + t->len) > sizeof(tx_data)) {
+ dev_dbg(sbsc->dev, "Command too big (%d)\n",
+ tx_len + t->len);
+ return -EIO;
+ }
+ memcpy(tx_data + tx_len, t->tx_buf, t->len);
+ tx_len += t->len;
+ }
+
+ if (t->rx_buf)
+ ret = spibsc_send_recv_data(sbsc, tx_data, tx_len,
+ t->rx_buf, t->len);
+
+ msg->actual_length += t->len;
+ }
+
+ msg->status = ret;
+ spi_finalize_current_message(master);
+
+ return ret;
+}
+
+static int spibsc_setup(struct spi_device *spi)
+{
+ struct spibsc_priv *sbsc = spi_controller_get_devdata(spi->master);
+ u32 max_speed_hz;
+ unsigned long rate;
+ u8 spbr;
+ u8 div_ratio;
+
+ if (spi->bits_per_word != 8) {
+ dev_err(sbsc->dev, "bits_per_word must be 8\n");
+ return -EIO;
+ }
+
+ if (sbsc->flags & HAS_SPBCR) {
+ max_speed_hz = spi->max_speed_hz;
+ rate = clk_get_rate(sbsc->clk);
+
+ div_ratio = 2;
+ spbr = 1;
+ while ((rate / div_ratio) > max_speed_hz) {
+ spbr++;
+ div_ratio += 2;
+ if (spbr == 255)
+ break;
+ }
+ spibsc_write(sbsc, SPBCR, SPBCR_SPBR(spbr) | SPBCR_BRDV(0));
+ dev_dbg(sbsc->dev, "Clock set to %ld Hz\n", rate/div_ratio);
+ }
+
+ return 0;
+}
+
+static int spibsc_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct spi_controller *master;
+ struct spibsc_priv *sbsc;
+ int ret;
+
+ master = spi_alloc_master(&pdev->dev, sizeof(*sbsc));
+ if (!master)
+ return -ENOMEM;
+
+ sbsc = spi_controller_get_devdata(master);
+ dev_set_drvdata(&pdev->dev, sbsc);
+ sbsc->master = master;
+ sbsc->dev = &pdev->dev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ sbsc->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(sbsc->base)) {
+ ret = PTR_ERR(sbsc->base);
+ goto error;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ sbsc->mmio_size = resource_size(res);
+ sbsc->mmio = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(sbsc->mmio)) {
+ ret = PTR_ERR(sbsc->mmio);
+ goto error;
+ }
+
+ sbsc->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(sbsc->clk)) {
+ dev_err(&pdev->dev, "cannot get clock\n");
+ ret = PTR_ERR(sbsc->clk);
+ goto error;
+ }
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_get_sync(&pdev->dev);
+
+ sbsc->flags = (u32) of_device_get_match_data(&pdev->dev);
+
+ master->bus_num = pdev->id;
+ master->num_chipselect = 1;
+ master->mode_bits = SPI_CPOL | SPI_CPHA;
+ master->setup = spibsc_setup;
+ master->transfer_one_message = spibsc_transfer_one_message;
+ master->dev.of_node = pdev->dev.of_node;
+
+ /* Initialize HW */
+ spibsc_write(sbsc, CMNCR, CMNCR_INIT);
+ spibsc_write(sbsc, DRCR, DRCR_RCF);
+ spibsc_write(sbsc, SSLDR, SSLDR_INIT);
+
+ ret = devm_spi_register_controller(&pdev->dev, master);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "spi_register_controller error.\n");
+ goto error;
+ }
+
+ dev_info(&pdev->dev, "probed\n");
+
+ return 0;
+
+error:
+ pm_runtime_put(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
+ spi_controller_put(master);
+
+ return ret;
+}
+
+static int spibsc_remove(struct platform_device *pdev)
+{
+ struct spibsc_priv *sbsc = dev_get_drvdata(&pdev->dev);
+
+ pm_runtime_put(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ spi_unregister_controller(sbsc->master);
+
+ return 0;
+}
+
+static const struct of_device_id of_spibsc_match[] = {
+ { .compatible = "renesas,spibsc"},
+ { .compatible = "renesas,r7s72100-spibsc", .data = (void *)HAS_SPBCR},
+ { .compatible = "renesas,r7s9210-spibsc"},
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, of_spibsc_match);
+
+static struct platform_driver spibsc_driver = {
+ .probe = spibsc_probe,
+ .remove = spibsc_remove,
+ .driver = {
+ .name = "spibsc",
+ .owner = THIS_MODULE,
+ .of_match_table = of_spibsc_match,
+ },
+};
+module_platform_driver(spibsc_driver);
+
+MODULE_DESCRIPTION("Renesas SPIBSC SPI Flash driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Chris Brandt");
--
2.23.0
