This driver uses SPI-MEM framework and is capable to operate with
single, dual, quad and octal SPI-NOR memories.
Low-level controller work mode (STIG) is utilized to communicate
with flash memories.

Signed-off-by: Jayshri Pawar <jpa...@cadence.com>
Signed-off-by: Konrad Kociolek <kon...@cadence.com>
---
 drivers/spi/Kconfig            |  11 +
 drivers/spi/Makefile           |   1 +
 drivers/spi/spi-cadence-xspi.c | 894 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 906 insertions(+)
 create mode 100644 drivers/spi/spi-cadence-xspi.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 5cff60d..a699c14 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -212,6 +212,17 @@ config SPI_CADENCE_QUADSPI
          device with a Cadence QSPI controller and want to access the
          Flash as an MTD device.
 
+config SPI_CADENCE_XSPI
+       tristate "Cadence XSPI controller"
+       depends on (OF || COMPILE_TEST) && HAS_IOMEM
+       help
+         Enable support for the Cadence XSPI Flash controller.
+
+         Cadence XSPI is a specialized controller for connecting an SPI
+         Flash over upto 8bit wide bus. Enable this option if you have a
+         device with a Cadence XSPI controller and want to access the
+         Flash as an MTD device.
+
 config SPI_CLPS711X
        tristate "CLPS711X host SPI controller"
        depends on ARCH_CLPS711X || COMPILE_TEST
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 6fea582..cb72cd6 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_SPI_BITBANG)             += spi-bitbang.o
 obj-$(CONFIG_SPI_BUTTERFLY)            += spi-butterfly.o
 obj-$(CONFIG_SPI_CADENCE)              += spi-cadence.o
 obj-$(CONFIG_SPI_CADENCE_QUADSPI)      += spi-cadence-quadspi.o
+obj-$(CONFIG_SPI_CADENCE_XSPI)         += spi-cadence-xspi.o
 obj-$(CONFIG_SPI_CLPS711X)             += spi-clps711x.o
 obj-$(CONFIG_SPI_COLDFIRE_QSPI)                += spi-coldfire-qspi.o
 obj-$(CONFIG_SPI_DAVINCI)              += spi-davinci.o
diff --git a/drivers/spi/spi-cadence-xspi.c b/drivers/spi/spi-cadence-xspi.c
new file mode 100644
index 0000000..fbf2aec
--- /dev/null
+++ b/drivers/spi/spi-cadence-xspi.c
@@ -0,0 +1,894 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Cadence XSPI flash controller driver
+ *
+ * Copyright (C) 2020 Cadence
+ *
+ * Author: Konrad Kociolek <kon...@cadence.com>
+ * Author: Jayshri Pawar <jpa...@cadence.com>
+ */
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/spi/spi.h>
+#include <linux/mtd/spi-nor.h>
+#include <linux/bitfield.h>
+#include <linux/limits.h>
+#include <linux/log2.h>
+
+#define CDNS_XSPI_MAGIC_NUM_VALUE               0x6522
+#define CDNS_XSPI_MAX_BANKS                     8
+#define CDNS_XSPI_NAME                          "cadence-xspi"
+
+/*
+ * Note: below are additional auxiliary registers to
+ * configure XSPI controller pin-strap settings
+ */
+
+/* PHY DQ timing register */
+#define CDNS_XSPI_CCP_PHY_DQ_TIMING           0x0000
+#define CDNS_XSPI_CCP_DATA_SELECT_OE_START    GENMASK(6, 4)
+#define CDNS_XSPI_CCP_DATA_SELECT_OE_END      GENMASK(2, 0)
+#define CDNS_XSPI_CCP_PHY_DQ_TIMING_INIT_VAL  0x80000000
+
+/* PHY DQS timing register */
+#define CDNS_XSPI_CCP_PHY_DQS_TIMING          0x0004
+#define CDNS_XSPI_CCP_USE_EXT_LPBCK_DQS       BIT(22)
+#define CDNS_XSPI_CCP_USE_LPBCK_DQS           BIT(21)
+#define CDNS_XSPI_CCP_USE_PHONY               BIT(20)
+#define CDNS_XSPI_CCP_DQS_SELECT_OE_START     GENMASK(7, 4)
+#define CDNS_XSPI_CCP_DQS_SELECT_OE_END       GENMASK(3, 0)
+
+/* PHY gate loopback control register */
+#define CDNS_XSPI_CCP_PHY_GATE_LPBCK_CTRL     0x0008
+#define CDNS_XSPI_CCP_READ_DATA_DELAY_SEL     GENMASK(24, 19)
+#define CDNS_XSPI_CCP_GATE_CFG_CLOSE          GENMASK(5, 4)
+#define CDNS_XSPI_CCP_GATE_CFG                GENMASK(3, 0)
+
+/* PHY DLL slave control register */
+#define CDNS_XSPI_CCP_PHY_DLL_SLAVE_CTRL      0x0010
+#define CDNS_XSPI_CCP_CLK_WR_DELAY            GENMASK(15, 8)
+#define CDNS_XSPI_CCP_READ_DQS_DELAY          GENMASK(7, 0)
+
+#define CDNS_XSPI_AUX_PHY_ADDONS_REG          0x0040
+#define CDNS_XSPI_AUX_PHY_ADDONS_VALUE        0xE0012000
+#define CDNS_XSPI_AUX_DEV_DISC_CONFIG_REG     0x0048
+#define CDNS_XSPI_AUX_DEV_DISC_CONFIG_VALUE   0x00000000
+#define CDNS_XSPI_AUX_DRIVING_REG             0x0050
+#define CDNS_XSPI_AUX_CTRL_RESET              BIT(0)
+
+/* DLL PHY control register */
+#define CDNS_XSPI_DLL_PHY_CTRL                0x1034
+#define CDNS_XSPI_CCP_DQS_LAST_DATA_DROP_EN   BIT(20)
+
+/* Command registers */
+#define CDNS_XSPI_CMD_REG_0                   0x0000
+#define CDNS_XSPI_CMD_REG_1                   0x0004
+#define CDNS_XSPI_CMD_REG_2                   0x0008
+#define CDNS_XSPI_CMD_REG_3                   0x000C
+#define CDNS_XSPI_CMD_REG_4                   0x0010
+#define CDNS_XSPI_CMD_REG_5                   0x0014
+
+/* Command status registers */
+#define CDNS_XSPI_CMD_STATUS_REG              0x0044
+#define CDNS_XSPI_CMD_COMPLETED               BIT(15)
+#define CDNS_XSPI_CMD_FAILED                  BIT(14)
+
+/* Controller status register */
+#define CDNS_XSPI_CTRL_STATUS_REG             0x0100
+#define CDNS_XSPI_INIT_COMPLETED              BIT(16)
+#define CDNS_XSPI_INIT_LEGACY                 BIT(9)
+#define CDNS_XSPI_INIT_FAIL                   BIT(8)
+#define CDNS_XSPI_CTRL_BUSY                   BIT(7)
+
+/* Controller interrupt status register */
+#define CDNS_XSPI_INTR_STATUS_REG             0x0110
+#define CDNS_XSPI_STIG_DONE                   BIT(23)
+#define CDNS_XSPI_SDMA_ERROR                  BIT(22)
+#define CDNS_XSPI_SDMA_TRIGGER                BIT(21)
+
+/* Controller interrupt enable register */
+#define CDNS_XSPI_INTR_ENABLE_REG             0x0114
+#define CDNS_XSPI_INTR_EN                     BIT(31)
+#define CDNS_XSPI_STIG_DONE_EN                BIT(23)
+#define CDNS_XSPI_SDMA_ERROR_EN               BIT(22)
+#define CDNS_XSPI_SDMA_TRIGGER_EN             BIT(21)
+
+#define CDNS_XSPI_INTR_MASK (CDNS_XSPI_INTR_EN | \
+       CDNS_XSPI_STIG_DONE_EN  | \
+       CDNS_XSPI_SDMA_ERROR_EN | \
+       CDNS_XSPI_SDMA_TRIGGER_EN)
+
+/* Controller config register */
+#define CDNS_XSPI_CTRL_CONFIG_REG             0x0230
+#define CDNS_XSPI_CTRL_WORK_MODE              GENMASK(6, 5)
+
+/* SDMA trigger transaction registers */
+#define CDNS_XSPI_SDMA_SIZE_REG               0x0240
+#define CDNS_XSPI_SDMA_TRD_INFO_REG           0x0244
+#define CDNS_XSPI_SDMA_DIR                    BIT(8)
+
+/* Controller features register */
+#define CDNS_XSPI_CTRL_FEATURES_REG           0x0F04
+#define CDNS_XSPI_NUM_BANKS                   GENMASK(25, 24)
+#define CDNS_XSPI_DMA_DATA_WIDTH              BIT(21)
+#define CDNS_XSPI_NUM_THREADS                 GENMASK(3, 0)
+
+/* Controller version register */
+#define CDNS_XSPI_CTRL_VERSION_REG            0x0F00
+#define CDNS_XSPI_MAGIC_NUM                   GENMASK(31, 16)
+#define CDNS_XSPI_CTRL_REV                    GENMASK(7, 0)
+
+/* STIG Profile 1.0 instruction fields (split into registers) */
+#define CDNS_XSPI_CMD_INSTR_TYPE              GENMASK(6, 0)
+#define CDNS_XSPI_CMD_P1_R1_ADDR0             GENMASK(31, 24)
+#define CDNS_XSPI_CMD_P1_R2_ADDR1             GENMASK(7, 0)
+#define CDNS_XSPI_CMD_P1_R2_ADDR2             GENMASK(15, 8)
+#define CDNS_XSPI_CMD_P1_R2_ADDR3             GENMASK(23, 16)
+#define CDNS_XSPI_CMD_P1_R2_ADDR4             GENMASK(31, 24)
+#define CDNS_XSPI_CMD_P1_R3_ADDR5             GENMASK(7, 0)
+#define CDNS_XSPI_CMD_P1_R3_CMD               GENMASK(23, 16)
+#define CDNS_XSPI_CMD_P1_R3_NUM_ADDR_BYTES    GENMASK(30, 28)
+#define CDNS_XSPI_CMD_P1_R4_ADDR_IOS          GENMASK(1, 0)
+#define CDNS_XSPI_CMD_P1_R4_CMD_IOS           GENMASK(9, 8)
+#define CDNS_XSPI_CMD_P1_R4_BANK              GENMASK(14, 12)
+
+/* STIG data sequence instruction fields (split into registers) */
+#define CDNS_XSPI_CMD_DSEQ_R2_DCNT_L          GENMASK(31, 16)
+#define CDNS_XSPI_CMD_DSEQ_R3_DCNT_H          GENMASK(15, 0)
+#define CDNS_XSPI_CMD_DSEQ_R3_NUM_OF_DUMMY    GENMASK(25, 20)
+#define CDNS_XSPI_CMD_DSEQ_R4_BANK            GENMASK(14, 12)
+#define CDNS_XSPI_CMD_DSEQ_R4_DATA_IOS        GENMASK(9, 8)
+#define CDNS_XSPI_CMD_DSEQ_R4_DIR             BIT(4)
+
+/* STIG command status fields */
+#define CDNS_XSPI_CMD_STATUS_COMPLETED        BIT(15)
+#define CDNS_XSPI_CMD_STATUS_FAILED           BIT(14)
+#define CDNS_XSPI_CMD_STATUS_DQS_ERROR        BIT(3)
+#define CDNS_XSPI_CMD_STATUS_CRC_ERROR        BIT(2)
+#define CDNS_XSPI_CMD_STATUS_BUS_ERROR        BIT(1)
+#define CDNS_XSPI_CMD_STATUS_INV_SEQ_ERROR    BIT(0)
+
+#define CDNS_XSPI_CTRL_WORK_MODE_STIG         0x01
+
+#define CDNS_XSPI_STIG_DONE_FLAG              BIT(0)
+
+/* Helper macros for filling command registers */
+#define CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_1(op, data_phase) ( \
+       FIELD_PREP(CDNS_XSPI_CMD_INSTR_TYPE, (data_phase) ? \
+               CDNS_XSPI_STIG_INSTR_TYPE_1 : CDNS_XSPI_STIG_INSTR_TYPE_0) | \
+       FIELD_PREP(CDNS_XSPI_CMD_P1_R1_ADDR0, op->addr.val & 0xff))
+
+#define CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_2(op) ( \
+       FIELD_PREP(CDNS_XSPI_CMD_P1_R2_ADDR1, (op->addr.val >> 8)  & 0xFF) | \
+       FIELD_PREP(CDNS_XSPI_CMD_P1_R2_ADDR2, (op->addr.val >> 16) & 0xFF) | \
+       FIELD_PREP(CDNS_XSPI_CMD_P1_R2_ADDR3, (op->addr.val >> 24) & 0xFF) | \
+       FIELD_PREP(CDNS_XSPI_CMD_P1_R2_ADDR4, (op->addr.val >> 32) & 0xFF))
+
+#define CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_3(op) ( \
+       FIELD_PREP(CDNS_XSPI_CMD_P1_R3_ADDR5, (op->addr.val >> 40) & 0xFF) | \
+       FIELD_PREP(CDNS_XSPI_CMD_P1_R3_CMD, op->cmd.opcode) | \
+       FIELD_PREP(CDNS_XSPI_CMD_P1_R3_NUM_ADDR_BYTES, op->addr.nbytes))
+
+#define CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_4(op, chipsel) ( \
+       FIELD_PREP(CDNS_XSPI_CMD_P1_R4_ADDR_IOS, ilog2(op->addr.buswidth)) | \
+       FIELD_PREP(CDNS_XSPI_CMD_P1_R4_CMD_IOS, ilog2(op->cmd.buswidth)) | \
+       FIELD_PREP(CDNS_XSPI_CMD_P1_R4_BANK, chipsel))
+
+#define CDNS_XSPI_CMD_FLD_DSEQ_CMD_1(op) \
+       FIELD_PREP(CDNS_XSPI_CMD_INSTR_TYPE, CDNS_XSPI_STIG_INSTR_TYPE_DATA_SEQ)
+
+#define CDNS_XSPI_CMD_FLD_DSEQ_CMD_2(op) \
+       FIELD_PREP(CDNS_XSPI_CMD_DSEQ_R2_DCNT_L, op->data.nbytes & 0xFFFF)
+
+#define CDNS_XSPI_CMD_FLD_DSEQ_CMD_3(op) ( \
+       FIELD_PREP(CDNS_XSPI_CMD_DSEQ_R3_DCNT_H, \
+               (op->data.nbytes >> 16) & 0xffff) | \
+       FIELD_PREP(CDNS_XSPI_CMD_DSEQ_R3_NUM_OF_DUMMY, op->dummy.nbytes * 8))
+
+#define CDNS_XSPI_CMD_FLD_DSEQ_CMD_4(op, chipsel) ( \
+       FIELD_PREP(CDNS_XSPI_CMD_DSEQ_R4_BANK, chipsel) | \
+       FIELD_PREP(CDNS_XSPI_CMD_DSEQ_R4_DATA_IOS, ilog2(op->data.buswidth)) | \
+       FIELD_PREP(CDNS_XSPI_CMD_DSEQ_R4_DIR, \
+               (op->data.dir == SPI_MEM_DATA_IN) ? \
+               CDNS_XSPI_STIG_CMD_DIR_READ : CDNS_XSPI_STIG_CMD_DIR_WRITE))
+
+enum cdns_xspi_stig_instr_type {
+       CDNS_XSPI_STIG_INSTR_TYPE_0,
+       CDNS_XSPI_STIG_INSTR_TYPE_1,
+       CDNS_XSPI_STIG_INSTR_TYPE_DATA_SEQ = 127,
+};
+
+enum cdns_xspi_sdma_dir {
+       CDNS_XSPI_SDMA_DIR_READ,
+       CDNS_XSPI_SDMA_DIR_WRITE,
+};
+
+enum cdns_xspi_stig_cmd_dir {
+       CDNS_XSPI_STIG_CMD_DIR_READ,
+       CDNS_XSPI_STIG_CMD_DIR_WRITE,
+};
+
+struct cdns_xspi_platform_data {
+       u32 phy_data_sel_oe_start;
+       u32 phy_data_sel_oe_end;
+       u32 phy_dqs_sel_oe_start;
+       u32 phy_dqs_sel_oe_end;
+       u32 phy_gate_cfg_close;
+       u32 phy_gate_cfg;
+       u32 phy_rd_del_sel;
+       u32 clk_wr_delay;
+       bool dqs_last_data_drop;
+       bool use_lpbk_dqs;
+       bool use_ext_lpbk_dqs;
+};
+
+struct cdns_xspi_dev {
+       struct platform_device *pdev;
+       struct device *dev;
+
+       void __iomem *iobase;
+       void __iomem *auxbase;
+       void __iomem *sdmabase;
+
+       int irq;
+       int current_cs;
+
+       struct mutex lock;
+
+       struct completion cmd_complete;
+       struct completion sdma_complete;
+       bool sdma_error;
+
+       void *in_buffer;
+       const void *out_buffer;
+
+       u8 hw_num_banks;
+
+       struct cdns_xspi_platform_data *plat_data;
+};
+
+static void cdns_xspi_controller_reset(struct cdns_xspi_dev *cdns_xspi)
+{
+       u32 driving_reg = 0;
+
+       driving_reg = readl(cdns_xspi->auxbase + CDNS_XSPI_AUX_DRIVING_REG);
+       driving_reg |= CDNS_XSPI_AUX_CTRL_RESET;
+       writel(driving_reg, cdns_xspi->auxbase + CDNS_XSPI_AUX_DRIVING_REG);
+
+       udelay(10);
+
+       driving_reg &= ~CDNS_XSPI_AUX_CTRL_RESET;
+       writel(driving_reg, cdns_xspi->auxbase + CDNS_XSPI_AUX_DRIVING_REG);
+}
+
+static int cdns_xspi_read_dqs_delay_training(struct cdns_xspi_dev *cdns_xspi)
+{
+       int rd_dqs_del;
+       int rd_dqs_del_min = -1;
+       int rd_dqs_del_max = -1;
+
+       u32 phy_dll_slave_ctrl = 0;
+       u32 ctrl_status = 0;
+
+       phy_dll_slave_ctrl = readl(cdns_xspi->auxbase +
+               CDNS_XSPI_CCP_PHY_DLL_SLAVE_CTRL);
+
+       for (rd_dqs_del = 0; rd_dqs_del < U8_MAX; rd_dqs_del++) {
+               phy_dll_slave_ctrl &= ~CDNS_XSPI_CCP_READ_DQS_DELAY;
+               phy_dll_slave_ctrl |= FIELD_PREP(CDNS_XSPI_CCP_READ_DQS_DELAY,
+                       rd_dqs_del);
+
+               writel(phy_dll_slave_ctrl,
+                       cdns_xspi->auxbase + CDNS_XSPI_CCP_PHY_DLL_SLAVE_CTRL);
+
+               cdns_xspi_controller_reset(cdns_xspi);
+
+               readl_relaxed_poll_timeout(cdns_xspi->iobase +
+                       CDNS_XSPI_CTRL_STATUS_REG, ctrl_status,
+                       (ctrl_status & CDNS_XSPI_INIT_COMPLETED), 10, 10000);
+
+               if (!(ctrl_status & CDNS_XSPI_INIT_COMPLETED) ||
+                       (ctrl_status & CDNS_XSPI_INIT_FAIL)) {
+                       if (rd_dqs_del_min != -1)
+                               rd_dqs_del_max = rd_dqs_del - 1;
+               } else {
+                       if (rd_dqs_del_min == -1)
+                               rd_dqs_del_min = rd_dqs_del;
+               }
+       }
+
+       if (rd_dqs_del_min == -1) {
+               dev_err(cdns_xspi->dev, "PHY training failed\n");
+               return -EBUSY;
+       } else if (rd_dqs_del_max == -1) {
+               rd_dqs_del_max = U8_MAX;
+       }
+
+       rd_dqs_del = rd_dqs_del_min + rd_dqs_del_max / 2;
+       dev_info(cdns_xspi->dev,
+               "Using optimal read_dqs_delay value: %d\n", rd_dqs_del);
+
+       phy_dll_slave_ctrl &= ~CDNS_XSPI_CCP_READ_DQS_DELAY;
+       phy_dll_slave_ctrl |= FIELD_PREP(CDNS_XSPI_CCP_READ_DQS_DELAY,
+               rd_dqs_del);
+
+       writel(phy_dll_slave_ctrl,
+               cdns_xspi->auxbase + CDNS_XSPI_CCP_PHY_DLL_SLAVE_CTRL);
+
+       return 0;
+}
+
+static int cdns_xspi_phy_init(struct cdns_xspi_dev *cdns_xspi)
+{
+       u32 xspi_dll_phy_ctrl = 0;
+       u32 phy_dq_timing = CDNS_XSPI_CCP_PHY_DQ_TIMING_INIT_VAL;
+       u32 phy_dqs_timing = 0;
+       u32 phy_gate_lpbck_ctrl = 0;
+       u32 phy_dll_slave_ctrl = 0;
+
+       if (cdns_xspi->plat_data->use_lpbk_dqs) {
+               phy_dqs_timing |= FIELD_PREP(CDNS_XSPI_CCP_USE_LPBCK_DQS, 1);
+
+               /*
+                * For XSPI protocol, phony_dqs and lpbk_dqs must
+                * have same value
+                */
+               phy_dqs_timing |= FIELD_PREP(CDNS_XSPI_CCP_USE_PHONY, 1);
+
+               if (cdns_xspi->plat_data->use_ext_lpbk_dqs)
+                       phy_dqs_timing |=
+                               FIELD_PREP(CDNS_XSPI_CCP_USE_EXT_LPBCK_DQS, 1);
+       }
+
+       xspi_dll_phy_ctrl = readl(cdns_xspi->auxbase + CDNS_XSPI_DLL_PHY_CTRL);
+
+       /* While using memory DQS last_data_drop parameter should be enabled */
+       if (cdns_xspi->plat_data->dqs_last_data_drop)
+               xspi_dll_phy_ctrl |=
+                       FIELD_PREP(CDNS_XSPI_CCP_DQS_LAST_DATA_DROP_EN, 1);
+
+       phy_dq_timing |= FIELD_PREP(CDNS_XSPI_CCP_DATA_SELECT_OE_START,
+               cdns_xspi->plat_data->phy_data_sel_oe_start);
+       phy_dq_timing |= FIELD_PREP(CDNS_XSPI_CCP_DATA_SELECT_OE_END,
+               cdns_xspi->plat_data->phy_data_sel_oe_end);
+
+       phy_dqs_timing |= FIELD_PREP(CDNS_XSPI_CCP_DQS_SELECT_OE_START,
+               cdns_xspi->plat_data->phy_dqs_sel_oe_start);
+       phy_dqs_timing |= FIELD_PREP(CDNS_XSPI_CCP_DQS_SELECT_OE_END,
+               cdns_xspi->plat_data->phy_dqs_sel_oe_end);
+
+       phy_gate_lpbck_ctrl |= FIELD_PREP(CDNS_XSPI_CCP_GATE_CFG_CLOSE,
+               cdns_xspi->plat_data->phy_gate_cfg_close);
+       phy_gate_lpbck_ctrl |= FIELD_PREP(CDNS_XSPI_CCP_GATE_CFG,
+               cdns_xspi->plat_data->phy_gate_cfg);
+       phy_gate_lpbck_ctrl |= FIELD_PREP(CDNS_XSPI_CCP_READ_DATA_DELAY_SEL,
+               cdns_xspi->plat_data->phy_rd_del_sel);
+
+       phy_dll_slave_ctrl |= FIELD_PREP(CDNS_XSPI_CCP_CLK_WR_DELAY,
+               cdns_xspi->plat_data->clk_wr_delay);
+
+       writel(xspi_dll_phy_ctrl,
+               cdns_xspi->auxbase + CDNS_XSPI_DLL_PHY_CTRL);
+       writel(phy_dq_timing,
+               cdns_xspi->auxbase + CDNS_XSPI_CCP_PHY_DQ_TIMING);
+       writel(phy_dqs_timing,
+               cdns_xspi->auxbase + CDNS_XSPI_CCP_PHY_DQS_TIMING);
+       writel(phy_gate_lpbck_ctrl,
+               cdns_xspi->auxbase + CDNS_XSPI_CCP_PHY_GATE_LPBCK_CTRL);
+       writel(phy_dll_slave_ctrl,
+               cdns_xspi->auxbase + CDNS_XSPI_CCP_PHY_DLL_SLAVE_CTRL);
+
+       writel(CDNS_XSPI_AUX_PHY_ADDONS_VALUE,
+               cdns_xspi->auxbase + CDNS_XSPI_AUX_PHY_ADDONS_REG);
+       writel(CDNS_XSPI_AUX_DEV_DISC_CONFIG_VALUE,
+               cdns_xspi->auxbase + CDNS_XSPI_AUX_DEV_DISC_CONFIG_REG);
+
+       return cdns_xspi_read_dqs_delay_training(cdns_xspi);
+}
+
+static int cdns_xspi_wait_for_controller_idle(struct cdns_xspi_dev *cdns_xspi)
+{
+       u32 ctrl_stat;
+
+       return readl_relaxed_poll_timeout(cdns_xspi->iobase +
+               CDNS_XSPI_CTRL_STATUS_REG,
+               ctrl_stat, ((ctrl_stat & CDNS_XSPI_CTRL_BUSY) == 0), 100, 1000);
+}
+
+static void cdns_xspi_trigger_command(struct cdns_xspi_dev *cdns_xspi,
+       u32 cmd_regs[5])
+{
+       writel(cmd_regs[5], cdns_xspi->iobase + CDNS_XSPI_CMD_REG_5);
+       writel(cmd_regs[4], cdns_xspi->iobase + CDNS_XSPI_CMD_REG_4);
+       writel(cmd_regs[3], cdns_xspi->iobase + CDNS_XSPI_CMD_REG_3);
+       writel(cmd_regs[2], cdns_xspi->iobase + CDNS_XSPI_CMD_REG_2);
+       writel(cmd_regs[1], cdns_xspi->iobase + CDNS_XSPI_CMD_REG_1);
+       writel(cmd_regs[0], cdns_xspi->iobase + CDNS_XSPI_CMD_REG_0);
+}
+
+static int cdns_xspi_check_command_status(struct cdns_xspi_dev *cdns_xspi)
+{
+       int ret = 0;
+       u32 cmd_status = readl(cdns_xspi->iobase + CDNS_XSPI_CMD_STATUS_REG);
+
+       if (cmd_status & CDNS_XSPI_CMD_STATUS_COMPLETED) {
+               if ((cmd_status & CDNS_XSPI_CMD_STATUS_FAILED) != 0) {
+                       if (cmd_status & CDNS_XSPI_CMD_STATUS_DQS_ERROR) {
+                               dev_err(cdns_xspi->dev,
+                                       "Incorrect DQS pulses were detected 
during data read operation\n");
+                               ret = -EPROTO;
+                       }
+                       if (cmd_status & CDNS_XSPI_CMD_STATUS_CRC_ERROR) {
+                               dev_err(cdns_xspi->dev,
+                                       "CRC error received from 
minicontroller\n");
+                               ret = -EPROTO;
+                       }
+                       if (cmd_status & CDNS_XSPI_CMD_STATUS_BUS_ERROR) {
+                               dev_err(cdns_xspi->dev,
+                                       "Controller got an error response on 
the system DMA interface\n");
+                               ret = -EPROTO;
+                       }
+                       if (cmd_status & CDNS_XSPI_CMD_STATUS_INV_SEQ_ERROR) {
+                               dev_err(cdns_xspi->dev,
+                                       "Invalid command sequence has been 
detected\n");
+                               ret = -EPROTO;
+                       }
+               }
+       } else {
+               dev_err(cdns_xspi->dev, "Fatal error - command not 
completed\n");
+               ret = -EPROTO;
+       }
+
+       return ret;
+}
+
+static void cdns_xspi_set_interrupts(struct cdns_xspi_dev *cdns_xspi,
+       bool enabled)
+{
+       u32 intr_enable;
+
+       intr_enable = readl(cdns_xspi->iobase + CDNS_XSPI_INTR_ENABLE_REG);
+       if (enabled)
+               intr_enable |= CDNS_XSPI_INTR_MASK;
+       else
+               intr_enable &= ~CDNS_XSPI_INTR_MASK;
+       writel(intr_enable, cdns_xspi->iobase + CDNS_XSPI_INTR_ENABLE_REG);
+}
+
+static int cdns_xspi_controller_init(struct cdns_xspi_dev *cdns_xspi)
+{
+       u32 ctrl_ver;
+       u32 ctrl_features;
+       u16 hw_magic_num;
+
+       ctrl_ver = readl(cdns_xspi->iobase + CDNS_XSPI_CTRL_VERSION_REG);
+       hw_magic_num = FIELD_GET(CDNS_XSPI_MAGIC_NUM, ctrl_ver);
+       if (hw_magic_num != CDNS_XSPI_MAGIC_NUM_VALUE) {
+               dev_err(cdns_xspi->dev,
+                       "Incorrect XSPI magic nunber: %x, expected: %x\n",
+                       hw_magic_num, CDNS_XSPI_MAGIC_NUM_VALUE);
+               return -EIO;
+       }
+
+       ctrl_features = readl(cdns_xspi->iobase + CDNS_XSPI_CTRL_FEATURES_REG);
+       cdns_xspi->hw_num_banks = FIELD_GET(CDNS_XSPI_NUM_BANKS, ctrl_features);
+
+       writel(FIELD_PREP(CDNS_XSPI_CTRL_WORK_MODE,
+               CDNS_XSPI_CTRL_WORK_MODE_STIG),
+               cdns_xspi->iobase + CDNS_XSPI_CTRL_CONFIG_REG);
+
+       cdns_xspi_set_interrupts(cdns_xspi, false);
+
+       return 0;
+}
+
+static void cdns_xspi_sdma_handle(struct cdns_xspi_dev *cdns_xspi)
+{
+       u32 sdma_size, sdma_trd_info;
+       u8 sdma_dir;
+
+       sdma_size = readl(cdns_xspi->iobase + CDNS_XSPI_SDMA_SIZE_REG);
+       sdma_trd_info = readl(cdns_xspi->iobase + CDNS_XSPI_SDMA_TRD_INFO_REG);
+       sdma_dir = FIELD_GET(CDNS_XSPI_SDMA_DIR, sdma_trd_info);
+
+       switch (sdma_dir) {
+       case CDNS_XSPI_SDMA_DIR_READ:
+               ioread8_rep(cdns_xspi->sdmabase,
+                       cdns_xspi->in_buffer, sdma_size);
+               break;
+
+       case CDNS_XSPI_SDMA_DIR_WRITE:
+               iowrite8_rep(cdns_xspi->sdmabase,
+                       cdns_xspi->out_buffer, sdma_size);
+               break;
+       }
+}
+
+static int cdns_xspi_send_stig_command(struct cdns_xspi_dev *cdns_xspi,
+       const struct spi_mem_op *op, bool data_phase)
+{
+       u32 cmd_regs[5] = {0};
+       u32 cmd_status;
+
+       cdns_xspi_wait_for_controller_idle(cdns_xspi);
+       cdns_xspi_set_interrupts(cdns_xspi, true);
+       cdns_xspi->sdma_error = false;
+
+       cmd_regs[1] = CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_1(op, data_phase);
+       cmd_regs[2] = CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_2(op);
+       cmd_regs[3] = CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_3(op);
+       cmd_regs[4] = CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_4(op,
+               cdns_xspi->current_cs);
+
+       cdns_xspi_trigger_command(cdns_xspi, cmd_regs);
+
+       if (data_phase) {
+
+               cmd_regs[0] = CDNS_XSPI_STIG_DONE_FLAG;
+
+               cmd_regs[1] = CDNS_XSPI_CMD_FLD_DSEQ_CMD_1(op);
+               cmd_regs[2] = CDNS_XSPI_CMD_FLD_DSEQ_CMD_2(op);
+               cmd_regs[3] = CDNS_XSPI_CMD_FLD_DSEQ_CMD_3(op);
+               cmd_regs[4] = CDNS_XSPI_CMD_FLD_DSEQ_CMD_4(op,
+                       cdns_xspi->current_cs);
+
+               cdns_xspi->in_buffer = op->data.buf.in;
+               cdns_xspi->out_buffer = op->data.buf.out;
+
+               cdns_xspi_trigger_command(cdns_xspi, cmd_regs);
+
+               wait_for_completion(&cdns_xspi->sdma_complete);
+               if (cdns_xspi->sdma_error) {
+                       cdns_xspi_set_interrupts(cdns_xspi, false);
+                       return -EIO;
+               }
+               cdns_xspi_sdma_handle(cdns_xspi);
+       }
+
+       wait_for_completion(&cdns_xspi->cmd_complete);
+
+       cmd_status = cdns_xspi_check_command_status(cdns_xspi);
+       cdns_xspi_set_interrupts(cdns_xspi, false);
+
+       if (cmd_status & CDNS_XSPI_CMD_STATUS_FAILED)
+               return -EPROTO;
+
+       return 0;
+}
+
+static int cdns_xspi_mem_op(struct cdns_xspi_dev *cdns_xspi,
+       struct spi_mem *mem, const struct spi_mem_op *op)
+{
+       if (cdns_xspi->current_cs != mem->spi->chip_select)
+               cdns_xspi->current_cs = mem->spi->chip_select;
+
+       return cdns_xspi_send_stig_command(cdns_xspi, op,
+               (op->data.dir != SPI_MEM_NO_DATA));
+}
+
+static int cdns_xspi_mem_op_execute(struct spi_mem *mem,
+       const struct spi_mem_op *op)
+{
+       struct cdns_xspi_dev *cdns_xspi =
+               spi_master_get_devdata(mem->spi->master);
+       int ret = 0;
+
+       mutex_lock(&cdns_xspi->lock);
+       ret = cdns_xspi_mem_op(cdns_xspi, mem, op);
+       mutex_unlock(&cdns_xspi->lock);
+
+       return ret;
+}
+
+static const struct spi_controller_mem_ops cadence_xspi_mem_ops = {
+       .exec_op = cdns_xspi_mem_op_execute,
+};
+
+static int cdns_xspi_setup(struct spi_device *spi_dev)
+{
+       if (spi_dev->chip_select > spi_dev->master->num_chipselect) {
+               dev_err(&spi_dev->dev,
+                       "%d chip-select is out of range\n",
+                       spi_dev->chip_select);
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static irqreturn_t cdns_xspi_irq_handler(int this_irq, void *dev)
+{
+       struct cdns_xspi_dev *cdns_xspi = dev;
+       u32 irq_status;
+       irqreturn_t result = IRQ_NONE;
+
+       irq_status = readl(cdns_xspi->iobase + CDNS_XSPI_INTR_STATUS_REG);
+       if (irq_status) {
+               writel(irq_status,
+                       cdns_xspi->iobase + CDNS_XSPI_INTR_STATUS_REG);
+
+               if (irq_status & CDNS_XSPI_SDMA_ERROR) {
+                       dev_err(cdns_xspi->dev, "Slave DMA transaction 
error\n");
+                       cdns_xspi->sdma_error = true;
+                       complete(&cdns_xspi->sdma_complete);
+               }
+
+               if (irq_status & CDNS_XSPI_SDMA_TRIGGER)
+                       complete(&cdns_xspi->sdma_complete);
+
+               if (irq_status & CDNS_XSPI_STIG_DONE)
+                       complete(&cdns_xspi->cmd_complete);
+
+               result = IRQ_HANDLED;
+       }
+
+       return result;
+}
+
+static int cdns_xspi_of_get_plat_data(struct platform_device *pdev)
+{
+       struct device_node *node_prop = pdev->dev.of_node;
+       struct device_node *node_child;
+       struct cdns_xspi_platform_data *plat_data = pdev->dev.platform_data;
+       unsigned int property;
+       unsigned int cs;
+
+       if (of_property_read_u32(node_prop,
+               "cdns,phy-data-select-oe-start", &property)) {
+               dev_err(&pdev->dev, "Couldn't determine data select oe 
start\n");
+               return -ENXIO;
+       }
+       plat_data->phy_data_sel_oe_start = property;
+
+       if (of_property_read_u32(node_prop,
+               "cdns,phy-data-select-oe-end", &property)) {
+               dev_err(&pdev->dev, "Couldn't determine data select oe end\n");
+               return -ENXIO;
+       }
+       plat_data->phy_data_sel_oe_end = property;
+
+       if (of_property_read_u32(node_prop,
+               "cdns,phy-dqs-select-oe-start", &property)) {
+               dev_err(&pdev->dev, "Couldn't determine DQS select oe start\n");
+               return -ENXIO;
+       }
+       plat_data->phy_dqs_sel_oe_start = property;
+
+       if (of_property_read_u32(node_prop,
+               "cdns,phy-dqs-select-oe-end", &property)) {
+               dev_err(&pdev->dev, "Couldn't determine DQS select oe end\n");
+               return -ENXIO;
+       }
+       plat_data->phy_dqs_sel_oe_end = property;
+
+       if (of_property_read_u32(node_prop,
+               "cdns,phy-gate-cfg-close", &property)) {
+               dev_err(&pdev->dev, "Couldn't determine gate config close\n");
+               return -ENXIO;
+       }
+       plat_data->phy_gate_cfg_close = property;
+
+       if (of_property_read_u32(node_prop,
+               "cdns,phy-gate-cfg", &property)) {
+               dev_err(&pdev->dev, "Couldn't determine gate config\n");
+               return -ENXIO;
+       }
+       plat_data->phy_gate_cfg = property;
+
+       if (of_property_read_u32(node_prop,
+               "cdns,phy-rd-del-select", &property)) {
+               dev_err(&pdev->dev, "Couldn't determine read delay select\n");
+               return -ENXIO;
+       }
+       plat_data->phy_rd_del_sel = property;
+
+       if (of_property_read_u32(node_prop,
+               "cdns,phy-clk-wr-delay", &property)) {
+               dev_err(&pdev->dev, "Couldn't determine clock write delay\n");
+               return -ENXIO;
+       }
+       plat_data->clk_wr_delay = property;
+
+       plat_data->dqs_last_data_drop = of_property_read_bool(node_prop,
+               "cdns,dqs-last-data-drop");
+       plat_data->use_lpbk_dqs = of_property_read_bool(node_prop,
+               "cdns,phy-use-lpbk-dqs");
+       plat_data->use_ext_lpbk_dqs = of_property_read_bool(node_prop,
+               "cdns,phy-use-ext-lpbk-dqs");
+
+       for_each_child_of_node(node_prop, node_child) {
+               if (!of_device_is_available(node_child))
+                       continue;
+
+               if (of_property_read_u32(node_child, "reg", &cs)) {
+                       dev_err(&pdev->dev, "Couldn't get memory chip 
select\n");
+                       return -ENXIO;
+               } else if (cs >= CDNS_XSPI_MAX_BANKS) {
+                       dev_err(&pdev->dev, "reg (cs) parameter value too 
large\n");
+                       return -ENXIO;
+               }
+       }
+
+       return 0;
+}
+
+static void cdns_xspi_print_phy_config(struct cdns_xspi_dev *cdns_xspi)
+{
+       struct device *dev = cdns_xspi->dev;
+
+       dev_info(dev, "PHY configuration\n");
+       dev_info(dev, "   * xspi_dll_phy_ctrl: %08x\n",
+               readl(cdns_xspi->iobase + CDNS_XSPI_DLL_PHY_CTRL));
+       dev_info(dev, "   * phy_dq_timing: %08x\n",
+               readl(cdns_xspi->auxbase + CDNS_XSPI_CCP_PHY_DQ_TIMING));
+       dev_info(dev, "   * phy_dqs_timing: %08x\n",
+               readl(cdns_xspi->auxbase + CDNS_XSPI_CCP_PHY_DQS_TIMING));
+       dev_info(dev, "   * phy_gate_loopback_ctrl: %08x\n",
+               readl(cdns_xspi->auxbase + CDNS_XSPI_CCP_PHY_GATE_LPBCK_CTRL));
+       dev_info(dev, "   * phy_dll_slave_ctrl: %08x\n",
+               readl(cdns_xspi->auxbase + CDNS_XSPI_CCP_PHY_DLL_SLAVE_CTRL));
+}
+
+static int cdns_xspi_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct spi_master *master = NULL;
+       struct resource *res = NULL;
+       struct cdns_xspi_dev *cdns_xspi = NULL;
+       struct cdns_xspi_platform_data *plat_data = NULL;
+       int ret;
+
+       master = spi_alloc_master(dev, sizeof(*cdns_xspi));
+       if (!master) {
+               ret = -ENOMEM;
+               dev_err(dev, "Failed to allocate memory for spi_master\n");
+               goto err_no_mem;
+       }
+
+       master->mode_bits = SPI_3WIRE | SPI_TX_DUAL  | SPI_TX_QUAD  |
+               SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_OCTAL | SPI_RX_OCTAL |
+               SPI_MODE_0  | SPI_MODE_3;
+
+       master->mem_ops = &cadence_xspi_mem_ops;
+       master->setup = cdns_xspi_setup;
+       master->dev.of_node = pdev->dev.of_node;
+       master->bus_num = -1;
+
+       platform_set_drvdata(pdev, master);
+
+       plat_data = devm_kmalloc(dev, sizeof(*plat_data), GFP_KERNEL);
+       if (!plat_data) {
+               ret = -ENOMEM;
+               dev_err(dev, "Failed to allocate memory for platform_data\n");
+               goto err_spi_master;
+       }
+       pdev->dev.platform_data = plat_data;
+
+       cdns_xspi = spi_master_get_devdata(master);
+       cdns_xspi->pdev = pdev;
+       cdns_xspi->dev = &pdev->dev;
+       cdns_xspi->current_cs = 0;
+       cdns_xspi->plat_data = plat_data;
+
+       init_completion(&cdns_xspi->cmd_complete);
+       init_completion(&cdns_xspi->sdma_complete);
+
+       ret = cdns_xspi_of_get_plat_data(pdev);
+       if (ret) {
+               ret = -ENODEV;
+               dev_err(dev, "Failed to get platform data\n");
+               goto err_spi_master;
+       }
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       cdns_xspi->iobase = devm_ioremap_resource(cdns_xspi->dev, res);
+       if (IS_ERR(cdns_xspi->iobase)) {
+               ret = PTR_ERR(cdns_xspi->iobase);
+               dev_err(dev, "Failed to remap controller base address\n");
+               goto err_spi_master;
+       }
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+       cdns_xspi->sdmabase = devm_ioremap_resource(cdns_xspi->dev, res);
+       if (IS_ERR(cdns_xspi->sdmabase)) {
+               ret = PTR_ERR(cdns_xspi->sdmabase);
+               dev_err(dev, "Failed to remap SDMA address\n");
+               goto err_spi_master;
+       }
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+       cdns_xspi->auxbase = devm_ioremap_resource(cdns_xspi->dev, res);
+       if (IS_ERR(cdns_xspi->auxbase)) {
+               ret = PTR_ERR(cdns_xspi->auxbase);
+               dev_err(dev, "Failed to remap AUX address\n");
+               goto err_spi_master;
+       }
+
+       cdns_xspi->irq = platform_get_irq(pdev, 0);
+       if (cdns_xspi->irq < 0) {
+               ret = -ENXIO;
+               dev_err(dev, "Failed to get IRQ\n");
+               goto err_spi_master;
+       }
+
+       ret = devm_request_irq(dev, cdns_xspi->irq, cdns_xspi_irq_handler,
+               IRQF_SHARED, pdev->name, cdns_xspi);
+       if (ret) {
+               dev_err(dev, "Failed to request IRQ: %d\n", cdns_xspi->irq);
+               goto err_spi_master;
+       }
+
+       ret = cdns_xspi_phy_init(cdns_xspi);
+       if (ret) {
+               dev_err(dev, "Failed to initialize PHY\n");
+               goto err_spi_master;
+       }
+
+       cdns_xspi_print_phy_config(cdns_xspi);
+
+       ret = cdns_xspi_controller_init(cdns_xspi);
+       if (ret) {
+               dev_err(dev, "Failed to initialize controller\n");
+               goto err_spi_master;
+       }
+
+       master->num_chipselect = 1 << cdns_xspi->hw_num_banks;
+
+       ret = devm_spi_register_master(dev, master);
+       if (ret) {
+               dev_err(dev, "Failed to register SPI master\n");
+               goto err_spi_master;
+       }
+
+       dev_info(dev, "Successfully registered SPI master\n");
+
+       return 0;
+
+err_spi_master:
+       spi_master_put(master);
+
+err_no_mem:
+       dev_err(dev, "Failed to probe Cadence XSPI controller driver\n");
+
+       return ret;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id cdns_xspi_of_match[] = {
+       {
+               .compatible = "cdns,xspi-nor-fpga",
+       },
+       { /* end of table */}
+};
+MODULE_DEVICE_TABLE(of, cdns_xspi_of_match);
+#else
+#define cdns_xspi_of_match NULL
+#endif /* CONFIG_OF */
+
+static struct platform_driver cdns_xspi_platform_driver = {
+       .probe          = cdns_xspi_probe,
+       .remove         = NULL,
+       .driver = {
+               .name = CDNS_XSPI_NAME,
+               .of_match_table = cdns_xspi_of_match,
+       },
+};
+
+module_platform_driver(cdns_xspi_platform_driver);
+
+MODULE_DESCRIPTION("Cadence XSPI Controller Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" CDNS_XSPI_NAME);
+MODULE_AUTHOR("Jayshri Pawar <jpa...@cadence.com>");
+MODULE_AUTHOR("Konrad Kociolek <kon...@cadence.com>");
-- 
2.7.4

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