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Subject[PATCH linux-next v6 8/8] mtd: atmel-quadspi: add driver for Atmel QSPI controller
Date
This driver add support to the new Atmel QSPI controller embedded into
sama5d2x SoCs. It expects a NOR memory to be connected to the QSPI
controller.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
---
drivers/mtd/spi-nor/Kconfig | 7 +
drivers/mtd/spi-nor/Makefile | 1 +
drivers/mtd/spi-nor/atmel-quadspi.c | 889 ++++++++++++++++++++++++++++++++++++
3 files changed, 897 insertions(+)
create mode 100644 drivers/mtd/spi-nor/atmel-quadspi.c

diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
index 89bf4c1faa2b..7a3d55429550 100644
--- a/drivers/mtd/spi-nor/Kconfig
+++ b/drivers/mtd/spi-nor/Kconfig
@@ -29,6 +29,13 @@ config SPI_FSL_QUADSPI
This controller does not support generic SPI. It only supports
SPI NOR.

+config SPI_ATMEL_QUADSPI
+ tristate "Atmel Quad SPI Controller"
+ depends on OF && HAS_DMA && (ARCH_AT91 || COMPILE_TEST)
+ help
+ This enables support for the Quad SPI controller in master mode.
+ We only connect the NOR to this controller now.
+
config SPI_NXP_SPIFI
tristate "NXP SPI Flash Interface (SPIFI)"
depends on OF && (ARCH_LPC18XX || COMPILE_TEST)
diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
index e53333ef8582..f5d23d7379bb 100644
--- a/drivers/mtd/spi-nor/Makefile
+++ b/drivers/mtd/spi-nor/Makefile
@@ -1,3 +1,4 @@
obj-$(CONFIG_MTD_SPI_NOR) += spi-nor.o
obj-$(CONFIG_SPI_FSL_QUADSPI) += fsl-quadspi.o
+obj-$(CONFIG_SPI_ATMEL_QUADSPI) += atmel-quadspi.o
obj-$(CONFIG_SPI_NXP_SPIFI) += nxp-spifi.o
diff --git a/drivers/mtd/spi-nor/atmel-quadspi.c b/drivers/mtd/spi-nor/atmel-quadspi.c
new file mode 100644
index 000000000000..dc0c1d8293d5
--- /dev/null
+++ b/drivers/mtd/spi-nor/atmel-quadspi.c
@@ -0,0 +1,889 @@
+/*
+ * Driver for Atmel QSPI Controller
+ *
+ * Copyright (C) 2015 Atmel Corporation
+ *
+ * Author: Cyrille Pitchen <cyrille.pitchen@atmel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * This driver is based on drivers/mtd/spi-nor/fsl-quadspi.c from Freescale.
+ */
+
+#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/spi-nor.h>
+#include <linux/platform_data/atmel.h>
+#include <linux/platform_data/dma-atmel.h>
+#include <linux/of.h>
+
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/pinctrl/consumer.h>
+
+/* QSPI register offsets */
+#define QSPI_CR 0x0000 /* Control Register */
+#define QSPI_MR 0x0004 /* Mode Register */
+#define QSPI_RD 0x0008 /* Receive Data Register */
+#define QSPI_TD 0x000c /* Transmit Data Register */
+#define QSPI_SR 0x0010 /* Status Register */
+#define QSPI_IER 0x0014 /* Interrupt Enable Register */
+#define QSPI_IDR 0x0018 /* Interrupt Disable Register */
+#define QSPI_IMR 0x001c /* Interrupt Mask Register */
+#define QSPI_SCR 0x0020 /* Serial Clock Register */
+
+#define QSPI_IAR 0x0030 /* Instruction Address Register */
+#define QSPI_ICR 0x0034 /* Instruction Code Register */
+#define QSPI_IFR 0x0038 /* Instruction Frame Register */
+
+#define QSPI_SMR 0x0040 /* Scrambling Mode Register */
+#define QSPI_SKR 0x0044 /* Scrambling Key Register */
+
+#define QSPI_WPMR 0x00E4 /* Write Protection Mode Register */
+#define QSPI_WPSR 0x00E8 /* Write Protection Status Register */
+
+#define QSPI_VERSION 0x00FC /* Version Register */
+
+
+/* Bitfields in QSPI_CR (Control Register) */
+#define QSPI_CR_QSPIEN BIT(0)
+#define QSPI_CR_QSPIDIS BIT(1)
+#define QSPI_CR_SWRST BIT(7)
+#define QSPI_CR_LASTXFER BIT(24)
+
+/* Bitfields in QSPI_MR (Mode Register) */
+#define QSPI_MR_SSM BIT(0)
+#define QSPI_MR_LLB BIT(1)
+#define QSPI_MR_WDRBT BIT(2)
+#define QSPI_MR_SMRM BIT(3)
+#define QSPI_MR_CSMODE_MASK GENMASK(5, 4)
+#define QSPI_MR_CSMODE_NOT_RELOADED (0 << 4)
+#define QSPI_MR_CSMODE_LASTXFER (1 << 4)
+#define QSPI_MR_CSMODE_SYSTEMATICALLY (2 << 4)
+#define QSPI_MR_NBBITS_MASK GENMASK(11, 8)
+#define QSPI_MR_NBBITS(n) ((((n) - 8) << 8) & QSPI_MR_NBBITS_MASK)
+#define QSPI_MR_DLYBCT_MASK GENMASK(23, 16)
+#define QSPI_MR_DLYBCT(n) (((n) << 16) & QSPI_MR_DLYBCT_MASK)
+#define QSPI_MR_DLYCS_MASK GENMASK(31, 24)
+#define QSPI_MR_DLYCS(n) (((n) << 24) & QSPI_MR_DLYCS_MASK)
+
+/* Bitfields in QSPI_SR/QSPI_IER/QSPI_IDR/QSPI_IMR */
+#define QSPI_SR_RDRF BIT(0)
+#define QSPI_SR_TDRE BIT(1)
+#define QSPI_SR_TXEMPTY BIT(2)
+#define QSPI_SR_OVRES BIT(3)
+#define QSPI_SR_CSR BIT(8)
+#define QSPI_SR_CSS BIT(9)
+#define QSPI_SR_INSTRE BIT(10)
+#define QSPI_SR_QSPIENS BIT(24)
+
+/* Bitfields in QSPI_SCR (Serial Clock Register) */
+#define QSPI_SCR_CPOL BIT(0)
+#define QSPI_SCR_CPHA BIT(1)
+#define QSPI_SCR_SCBR_MASK GENMASK(15, 8)
+#define QSPI_SCR_SCBR(n) (((n) << 8) & QSPI_SCR_SCBR_MASK)
+#define QSPI_SCR_DLYBS_MASK GENMASK(23, 16)
+#define QSPI_SCR_DLYBS(n) (((n) << 16) & QSPI_SCR_DLYBS_MASK)
+
+/* Bitfields in QSPI_ICR (Instruction Code Register) */
+#define QSPI_ICR_INST_MASK GENMASK(7, 0)
+#define QSPI_ICR_INST(inst) (((inst) << 0) & QSPI_ICR_INST_MASK)
+#define QSPI_ICR_OPT_MASK GENMASK(23, 16)
+#define QSPI_ICR_OPT(opt) (((opt) << 16) & QSPI_ICR_OPT_MASK)
+
+/* Bitfields in QSPI_IFR (Instruction Frame Register) */
+#define QSPI_IFR_WIDTH_MASK GENMASK(2, 0)
+#define QSPI_IFR_WIDTH_SINGLE_BIT_SPI (0 << 0)
+#define QSPI_IFR_WIDTH_DUAL_OUTPUT (1 << 0)
+#define QSPI_IFR_WIDTH_QUAD_OUTPUT (2 << 0)
+#define QSPI_IFR_WIDTH_DUAL_IO (3 << 0)
+#define QSPI_IFR_WIDTH_QUAD_IO (4 << 0)
+#define QSPI_IFR_WIDTH_DUAL_CMD (5 << 0)
+#define QSPI_IFR_WIDTH_QUAD_CMD (6 << 0)
+#define QSPI_IFR_INSTEN BIT(4)
+#define QSPI_IFR_ADDREN BIT(5)
+#define QSPI_IFR_OPTEN BIT(6)
+#define QSPI_IFR_DATAEN BIT(7)
+#define QSPI_IFR_OPTL_MASK GENMASK(9, 8)
+#define QSPI_IFR_OPTL_1BIT (0 << 8)
+#define QSPI_IFR_OPTL_2BIT (1 << 8)
+#define QSPI_IFR_OPTL_4BIT (2 << 8)
+#define QSPI_IFR_OPTL_8BIT (3 << 8)
+#define QSPI_IFR_ADDRL BIT(10)
+#define QSPI_IFR_TFRTYP_MASK GENMASK(13, 12)
+#define QSPI_IFR_TFRTYP_TRSFR_READ (0 << 12)
+#define QSPI_IFR_TFRTYP_TRSFR_READ_MEM (1 << 12)
+#define QSPI_IFR_TFRTYP_TRSFR_WRITE (2 << 12)
+#define QSPI_IFR_TFRTYP_TRSFR_WRITE_MEM (3 << 13)
+#define QSPI_IFR_CRM BIT(14)
+#define QSPI_IFR_NBDUM_MASK GENMASK(20, 16)
+#define QSPI_IFR_NBDUM(n) (((n) << 16) & QSPI_IFR_NBDUM_MASK)
+
+/* Bitfields in QSPI_SMR (Scrambling Mode Register) */
+#define QSPI_SMR_SCREN BIT(0)
+#define QSPI_SMR_RVDIS BIT(1)
+
+/* Bitfields in QSPI_WPMR (Write Protection Mode Register) */
+#define QSPI_WPMR_WPEN BIT(0)
+#define QSPI_WPMR_WPKEY_MASK GENMASK(31, 8)
+#define QSPI_WPMR_WPKEY(wpkey) (((wpkey) << 8) & QSPI_WPMR_WPKEY_MASK)
+
+/* Bitfields in QSPI_WPSR (Write Protection Status Register) */
+#define QSPI_WPSR_WPVS BIT(0)
+#define QSPI_WPSR_WPVSRC_MASK GENMASK(15, 8)
+#define QSPI_WPSR_WPVSRC(src) (((src) << 8) & QSPI_WPSR_WPVSRC)
+
+
+struct atmel_qspi {
+ void __iomem *regs;
+ void __iomem *mem;
+ dma_addr_t phys_addr;
+ struct dma_chan *chan;
+ struct clk *clk;
+ struct platform_device *pdev;
+ u32 pending;
+
+ struct mtd_info mtd;
+ struct spi_nor nor;
+ u32 clk_rate;
+ struct completion cmd_completion;
+ struct completion dma_completion;
+
+#ifdef DEBUG
+ u8 last_instruction;
+#endif
+};
+
+struct atmel_qspi_command {
+ u32 ifr;
+ union {
+ struct {
+ u32 instruction:1;
+ u32 address:3;
+ u32 mode:1;
+ u32 dummy:1;
+ u32 data:1;
+ u32 dma:1;
+ u32 reserved:24;
+ } bits;
+ u32 word;
+ } enable;
+ u8 instruction;
+ u8 mode;
+ u8 num_mode_cycles;
+ u8 num_dummy_cycles;
+ u32 address;
+
+ size_t buf_len;
+ const void *tx_buf;
+ void *rx_buf;
+};
+
+/* Register access functions */
+static inline u32 qspi_readl(struct atmel_qspi *aq, u32 reg)
+{
+ return readl_relaxed(aq->regs + reg);
+}
+
+static inline void qspi_writel(struct atmel_qspi *aq, u32 reg, u32 value)
+{
+ writel_relaxed(value, aq->regs + reg);
+}
+
+
+#define QSPI_DMA_THRESHOLD 32
+
+static void atmel_qspi_dma_callback(void *arg)
+{
+ struct completion *dma_completion = arg;
+
+ complete(dma_completion);
+}
+
+static int atmel_qspi_run_dma_transfer(struct atmel_qspi *aq,
+ const struct atmel_qspi_command *cmd)
+{
+ u32 offset = (cmd->enable.bits.address) ? cmd->address : 0;
+ struct dma_chan *chan = aq->chan;
+ struct device *dev = &aq->pdev->dev;
+ enum dma_data_direction direction;
+ dma_addr_t phys_addr, dst, src;
+ struct dma_async_tx_descriptor *desc;
+ dma_cookie_t cookie;
+ int err = 0;
+
+ if (cmd->tx_buf) {
+ direction = DMA_TO_DEVICE;
+ phys_addr = dma_map_single(dev, (void *)cmd->tx_buf,
+ cmd->buf_len, direction);
+ src = phys_addr;
+ dst = aq->phys_addr + offset;
+ } else {
+ direction = DMA_FROM_DEVICE;
+ phys_addr = dma_map_single(dev, (void *)cmd->rx_buf,
+ cmd->buf_len, direction);
+ src = aq->phys_addr + offset;
+ dst = phys_addr;
+ }
+ if (dma_mapping_error(dev, phys_addr))
+ return -ENOMEM;
+
+ desc = chan->device->device_prep_dma_memcpy(chan, dst, src,
+ cmd->buf_len,
+ DMA_PREP_INTERRUPT);
+ if (!desc) {
+ err = -ENOMEM;
+ goto unmap_single;
+ }
+
+ reinit_completion(&aq->dma_completion);
+ desc->callback = atmel_qspi_dma_callback;
+ desc->callback_param = &aq->dma_completion;
+ cookie = dmaengine_submit(desc);
+ err = dma_submit_error(cookie);
+ if (err)
+ goto unmap_single;
+ dma_async_issue_pending(chan);
+
+ if (!wait_for_completion_timeout(&aq->dma_completion,
+ msecs_to_jiffies(1000)))
+ err = -ETIMEDOUT;
+
+ if (dma_async_is_tx_complete(chan, cookie, NULL, NULL) != DMA_COMPLETE)
+ err = -ETIMEDOUT;
+
+ if (err)
+ dmaengine_terminate_all(chan);
+unmap_single:
+ dma_unmap_single(dev, phys_addr, cmd->buf_len, direction);
+
+ return err;
+}
+
+static int atmel_qspi_run_transfer(struct atmel_qspi *aq,
+ const struct atmel_qspi_command *cmd)
+{
+ void __iomem *ahb_mem;
+
+ /* First try a DMA transfer */
+ if (aq->chan && cmd->enable.bits.dma &&
+ cmd->buf_len >= QSPI_DMA_THRESHOLD)
+ return atmel_qspi_run_dma_transfer(aq, cmd);
+
+ /* Then fallback to a PIO transfer */
+ ahb_mem = aq->mem;
+ if (cmd->enable.bits.address)
+ ahb_mem += cmd->address;
+ if (cmd->tx_buf)
+ memcpy_toio(ahb_mem, cmd->tx_buf, cmd->buf_len);
+ else
+ memcpy_fromio(cmd->rx_buf, ahb_mem, cmd->buf_len);
+
+ return 0;
+}
+
+#ifdef DEBUG
+static void atmel_qspi_debug_command(struct atmel_qspi *aq,
+ const struct atmel_qspi_command *cmd)
+{
+ u8 cmd_buf[SPI_NOR_MAX_CMD_SIZE];
+ size_t len = 0;
+ int i;
+
+ if (cmd->enable.bits.instruction) {
+ if (aq->last_instruction == cmd->instruction)
+ return;
+ aq->last_instruction = cmd->instruction;
+ }
+
+ if (cmd->enable.bits.instruction)
+ cmd_buf[len++] = cmd->instruction;
+
+ for (i = cmd->enable.bits.address-1; i >= 0; --i)
+ cmd_buf[len++] = (cmd->address >> (i << 3)) & 0xff;
+
+ if (cmd->enable.bits.mode)
+ cmd_buf[len++] = cmd->mode;
+
+ if (cmd->enable.bits.dummy) {
+ int num = cmd->num_dummy_cycles;
+
+ switch (cmd->ifr & QSPI_IFR_WIDTH_MASK) {
+ case QSPI_IFR_WIDTH_SINGLE_BIT_SPI:
+ case QSPI_IFR_WIDTH_DUAL_OUTPUT:
+ case QSPI_IFR_WIDTH_QUAD_OUTPUT:
+ num >>= 3;
+ break;
+ case QSPI_IFR_WIDTH_DUAL_IO:
+ case QSPI_IFR_WIDTH_DUAL_CMD:
+ num >>= 2;
+ break;
+ case QSPI_IFR_WIDTH_QUAD_IO:
+ case QSPI_IFR_WIDTH_QUAD_CMD:
+ num >>= 1;
+ break;
+ default:
+ return;
+ }
+
+ for (i = 0; i < num; ++i)
+ cmd_buf[len++] = 0;
+ }
+
+ /* Dump the SPI command */
+ print_hex_dump(KERN_DEBUG, "qspi cmd: ", DUMP_PREFIX_NONE,
+ 32, 1, cmd_buf, len, false);
+
+#ifdef VERBOSE_DEBUG
+ /* If verbose debug is enabled, also dump the TX data */
+ if (cmd->enable.bits.data && cmd->tx_buf)
+ print_hex_dump(KERN_DEBUG, "qspi tx : ", DUMP_PREFIX_NONE,
+ 32, 1, cmd->tx_buf, cmd->buf_len, false);
+#endif
+}
+#else
+#define atmel_qspi_debug_command(aq, cmd)
+#endif
+
+static int atmel_qspi_run_command(struct atmel_qspi *aq,
+ const struct atmel_qspi_command *cmd)
+{
+ u32 iar, icr, ifr, sr;
+ int err = 0;
+
+ iar = 0;
+ icr = 0;
+ ifr = cmd->ifr;
+
+ /* Compute instruction parameters */
+ if (cmd->enable.bits.instruction) {
+ icr |= QSPI_ICR_INST(cmd->instruction);
+ ifr |= QSPI_IFR_INSTEN;
+ }
+
+ /* Compute address parameters */
+ switch (cmd->enable.bits.address) {
+ case 4:
+ ifr |= QSPI_IFR_ADDRL;
+ /* fall through to the 24bit (3 byte) address case. */
+ case 3:
+ iar = (cmd->enable.bits.data) ? 0 : cmd->address;
+ ifr |= QSPI_IFR_ADDREN;
+ break;
+ case 0:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /* Compute option parameters */
+ if (cmd->enable.bits.mode && cmd->num_mode_cycles) {
+ u32 mode_cycle_bits, mode_bits;
+
+ icr |= QSPI_ICR_OPT(cmd->mode);
+ ifr |= QSPI_IFR_OPTEN;
+
+ switch (ifr & QSPI_IFR_WIDTH_MASK) {
+ case QSPI_IFR_WIDTH_SINGLE_BIT_SPI:
+ case QSPI_IFR_WIDTH_DUAL_OUTPUT:
+ case QSPI_IFR_WIDTH_QUAD_OUTPUT:
+ mode_cycle_bits = 1;
+ break;
+ case QSPI_IFR_WIDTH_DUAL_IO:
+ case QSPI_IFR_WIDTH_DUAL_CMD:
+ mode_cycle_bits = 2;
+ break;
+ case QSPI_IFR_WIDTH_QUAD_IO:
+ case QSPI_IFR_WIDTH_QUAD_CMD:
+ mode_cycle_bits = 4;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ mode_bits = cmd->num_mode_cycles * mode_cycle_bits;
+ switch (mode_bits) {
+ case 1:
+ ifr |= QSPI_IFR_OPTL_1BIT;
+ break;
+
+ case 2:
+ ifr |= QSPI_IFR_OPTL_2BIT;
+ break;
+
+ case 4:
+ ifr |= QSPI_IFR_OPTL_4BIT;
+ break;
+
+ case 8:
+ ifr |= QSPI_IFR_OPTL_8BIT;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ }
+
+ /* Set number of dummy cycles */
+ if (cmd->enable.bits.dummy)
+ ifr |= QSPI_IFR_NBDUM(cmd->num_dummy_cycles);
+
+ /* Set data enable */
+ if (cmd->enable.bits.data) {
+ ifr |= QSPI_IFR_DATAEN;
+
+ /* Special case for Continuous Read Mode */
+ if (!cmd->tx_buf && !cmd->rx_buf)
+ ifr |= QSPI_IFR_CRM;
+ }
+
+ /* Set QSPI Instruction Frame registers */
+ atmel_qspi_debug_command(aq, cmd);
+ qspi_writel(aq, QSPI_IAR, iar);
+ qspi_writel(aq, QSPI_ICR, icr);
+ qspi_writel(aq, QSPI_IFR, ifr);
+
+ /* Skip to the final steps if there is no data */
+ if (!cmd->enable.bits.data)
+ goto no_data;
+
+ /* Dummy read of QSPI_IFR to synchronize APB and AHB accesses */
+ (void)qspi_readl(aq, QSPI_IFR);
+
+ /* Stop here for continuous read */
+ if (!cmd->tx_buf && !cmd->rx_buf)
+ return 0;
+ /* Send/Receive data */
+ err = atmel_qspi_run_transfer(aq, cmd);
+
+ /* Release the chip-select */
+ qspi_writel(aq, QSPI_CR, QSPI_CR_LASTXFER);
+
+ if (err)
+ return err;
+
+#if defined(DEBUG) && defined(VERBOSE_DEBUG)
+ /*
+ * If verbose debug is enabled, also dump the RX data in addition to
+ * the SPI command previously dumped by atmel_qspi_debug_command()
+ */
+ if (cmd->rx_buf)
+ print_hex_dump(KERN_DEBUG, "qspi rx : ", DUMP_PREFIX_NONE,
+ 32, 1, cmd->rx_buf, cmd->buf_len, false);
+#endif
+no_data:
+ /* Poll INSTRuction End status */
+ sr = qspi_readl(aq, QSPI_SR);
+ if (sr & QSPI_SR_INSTRE)
+ return err;
+
+ /* Wait for INSTRuction End interrupt */
+ reinit_completion(&aq->cmd_completion);
+ aq->pending = 0;
+ qspi_writel(aq, QSPI_IER, QSPI_SR_INSTRE);
+ if (!wait_for_completion_timeout(&aq->cmd_completion,
+ msecs_to_jiffies(1000)))
+ err = -ETIMEDOUT;
+ qspi_writel(aq, QSPI_IDR, QSPI_SR_INSTRE);
+
+ return err;
+}
+
+static int atmel_qspi_command_set_ifr(struct atmel_qspi_command *cmd,
+ u32 ifr_tfrtyp,
+ enum spi_protocol proto)
+{
+ cmd->ifr = ifr_tfrtyp;
+
+ switch (proto) {
+ case SPI_PROTO_1_1_1:
+ cmd->ifr |= QSPI_IFR_WIDTH_SINGLE_BIT_SPI;
+ break;
+ case SPI_PROTO_1_1_2:
+ cmd->ifr |= QSPI_IFR_WIDTH_DUAL_OUTPUT;
+ break;
+ case SPI_PROTO_1_1_4:
+ cmd->ifr |= QSPI_IFR_WIDTH_QUAD_OUTPUT;
+ break;
+ case SPI_PROTO_1_2_2:
+ cmd->ifr |= QSPI_IFR_WIDTH_DUAL_IO;
+ break;
+ case SPI_PROTO_1_4_4:
+ cmd->ifr |= QSPI_IFR_WIDTH_QUAD_IO;
+ break;
+ case SPI_PROTO_2_2_2:
+ cmd->ifr |= QSPI_IFR_WIDTH_DUAL_CMD;
+ break;
+ case SPI_PROTO_4_4_4:
+ cmd->ifr |= QSPI_IFR_WIDTH_QUAD_CMD;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int atmel_qspi_read_reg(struct spi_nor *nor, u8 opcode,
+ u8 *buf, int len)
+{
+ struct atmel_qspi *aq = nor->priv;
+ struct atmel_qspi_command cmd;
+ int ret;
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.enable.bits.instruction = 1;
+ cmd.enable.bits.data = 1;
+ cmd.instruction = opcode;
+ cmd.rx_buf = buf;
+ cmd.buf_len = len;
+
+ ret = atmel_qspi_command_set_ifr(&cmd,
+ QSPI_IFR_TFRTYP_TRSFR_READ,
+ nor->reg_proto);
+ if (ret)
+ return ret;
+
+ return atmel_qspi_run_command(aq, &cmd);
+}
+
+static int atmel_qspi_write_reg(struct spi_nor *nor, u8 opcode,
+ u8 *buf, int len,
+ int write_enable)
+{
+ struct atmel_qspi *aq = nor->priv;
+ struct atmel_qspi_command cmd;
+ int ret;
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.enable.bits.instruction = 1;
+ cmd.enable.bits.data = (buf != NULL && len > 0);
+ cmd.instruction = opcode;
+ cmd.tx_buf = buf;
+ cmd.buf_len = len;
+
+ ret = atmel_qspi_command_set_ifr(&cmd,
+ QSPI_IFR_TFRTYP_TRSFR_WRITE,
+ nor->reg_proto);
+ if (ret)
+ return ret;
+
+ return atmel_qspi_run_command(aq, &cmd);
+}
+
+static void atmel_qspi_write(struct spi_nor *nor, loff_t to, size_t len,
+ size_t *retlen, const u_char *write_buf)
+{
+ struct atmel_qspi *aq = nor->priv;
+ struct atmel_qspi_command cmd;
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.enable.bits.instruction = 1;
+ cmd.enable.bits.address = nor->addr_width;
+ cmd.enable.bits.data = 1;
+ cmd.enable.bits.dma = 1;
+ cmd.instruction = nor->program_opcode;
+ cmd.address = (u32)to;
+ cmd.tx_buf = write_buf;
+ cmd.buf_len = len;
+
+ if (atmel_qspi_command_set_ifr(&cmd,
+ QSPI_IFR_TFRTYP_TRSFR_WRITE_MEM,
+ nor->write_proto))
+ return;
+
+ if (!atmel_qspi_run_command(aq, &cmd))
+ *retlen += len;
+}
+
+static int atmel_qspi_erase(struct spi_nor *nor, loff_t offs)
+{
+ struct atmel_qspi *aq = nor->priv;
+ struct atmel_qspi_command cmd;
+ int ret;
+
+ dev_dbg(nor->dev, "%dKiB at 0x%08x\n",
+ aq->mtd.erasesize / 1024, (u32)offs);
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.enable.bits.instruction = 1;
+ cmd.enable.bits.address = nor->addr_width;
+ cmd.instruction = nor->erase_opcode;
+ cmd.address = (u32)offs;
+
+ ret = atmel_qspi_command_set_ifr(&cmd,
+ QSPI_IFR_TFRTYP_TRSFR_WRITE,
+ nor->erase_proto);
+ if (ret)
+ return ret;
+
+ return atmel_qspi_run_command(aq, &cmd);
+}
+
+static int atmel_qspi_read(struct spi_nor *nor, loff_t from, size_t len,
+ size_t *retlen, u_char *read_buf)
+{
+ struct atmel_qspi *aq = nor->priv;
+ struct atmel_qspi_command cmd;
+ int ret;
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.enable.bits.instruction = 1;
+ cmd.enable.bits.address = nor->addr_width;
+ cmd.enable.bits.dummy = (nor->read_dummy > 0);
+ cmd.enable.bits.data = 1;
+ cmd.enable.bits.dma = 1;
+ cmd.instruction = nor->read_opcode;
+ cmd.address = (u32)from;
+ cmd.num_dummy_cycles = nor->read_dummy;
+ cmd.rx_buf = read_buf;
+ cmd.buf_len = len;
+
+ ret = atmel_qspi_command_set_ifr(&cmd,
+ QSPI_IFR_TFRTYP_TRSFR_READ_MEM,
+ nor->read_proto);
+ if (ret)
+ return ret;
+
+ ret = atmel_qspi_run_command(aq, &cmd);
+ if (ret)
+ return ret;
+
+ *retlen += len;
+ return 0;
+}
+
+static int atmel_qspi_init(struct atmel_qspi *aq)
+{
+ unsigned long src_rate;
+ u32 mr, scr, scbr;
+
+ /* Reset the QSPI controller */
+ qspi_writel(aq, QSPI_CR, QSPI_CR_SWRST);
+
+ /* Set the QSPI controller in Serial Memory Mode */
+ mr = QSPI_MR_SSM | QSPI_MR_NBBITS(8);
+ qspi_writel(aq, QSPI_MR, mr);
+
+ src_rate = clk_get_rate(aq->clk);
+ if (!src_rate)
+ return -EINVAL;
+
+ /* Compute the QSPI baudrate */
+ scbr = DIV_ROUND_UP(src_rate, aq->clk_rate);
+ if (scbr > 0)
+ scbr--;
+ scr = QSPI_SCR_SCBR(scbr);
+ qspi_writel(aq, QSPI_SCR, scr);
+
+ /* Enable the QSPI controller */
+ qspi_writel(aq, QSPI_CR, QSPI_CR_QSPIEN);
+
+ return 0;
+}
+
+static irqreturn_t atmel_qspi_interrupt(int irq, void *dev_id)
+{
+ struct atmel_qspi *aq = (struct atmel_qspi *)dev_id;
+ u32 status, mask, pending;
+
+ status = qspi_readl(aq, QSPI_SR);
+ mask = qspi_readl(aq, QSPI_IMR);
+ pending = status & mask;
+
+ if (!pending)
+ return IRQ_NONE;
+
+ aq->pending |= pending;
+ if (pending & QSPI_SR_INSTRE)
+ complete(&aq->cmd_completion);
+
+ return IRQ_HANDLED;
+}
+
+static int atmel_qspi_probe(struct platform_device *pdev)
+{
+ struct device_node *child, *np = pdev->dev.of_node;
+ struct mtd_part_parser_data ppdata;
+ struct atmel_qspi *aq;
+ struct resource *res;
+ dma_cap_mask_t mask;
+ struct spi_nor *nor;
+ struct mtd_info *mtd;
+ char modalias[40];
+ int irq, err = 0;
+
+ if (of_get_child_count(np) != 1)
+ return -ENODEV;
+ child = of_get_next_child(np, NULL);
+
+ aq = devm_kzalloc(&pdev->dev, sizeof(*aq), GFP_KERNEL);
+ if (!aq) {
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ platform_set_drvdata(pdev, aq);
+ init_completion(&aq->cmd_completion);
+ init_completion(&aq->dma_completion);
+ aq->pdev = pdev;
+
+ /* Map the registers */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ aq->regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(aq->regs)) {
+ dev_err(&pdev->dev, "missing registers\n");
+ err = PTR_ERR(aq->regs);
+ goto exit;
+ }
+
+ /* Map the AHB memory */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ aq->mem = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(aq->mem)) {
+ dev_err(&pdev->dev, "missing AHB memory\n");
+ err = PTR_ERR(aq->regs);
+ goto exit;
+ }
+ aq->phys_addr = (dma_addr_t)res->start;
+
+ /* Get the peripheral clock */
+ aq->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(aq->clk)) {
+ dev_err(&pdev->dev, "missing peripheral clock\n");
+ err = PTR_ERR(aq->clk);
+ goto exit;
+ }
+
+ /* Enable the peripheral clock */
+ err = clk_prepare_enable(aq->clk);
+ if (err) {
+ dev_err(&pdev->dev, "failed to enable the peripheral clock\n");
+ goto exit;
+ }
+
+ /* Request the IRQ */
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "missing IRQ\n");
+ err = irq;
+ goto disable_clk;
+ }
+ err = devm_request_irq(&pdev->dev, irq, atmel_qspi_interrupt,
+ 0, dev_name(&pdev->dev), aq);
+ if (err)
+ goto disable_clk;
+
+ /* Try to get a DMA channel for memcpy() operation */
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_MEMCPY, mask);
+ aq->chan = dma_request_channel(mask, NULL, NULL);
+ if (!aq->chan)
+ dev_warn(&pdev->dev, "no available DMA channel\n");
+
+ /* Setup the spi-nor */
+ nor = &aq->nor;
+ mtd = &aq->mtd;
+
+ nor->mtd = mtd;
+ nor->dev = &pdev->dev;
+ nor->priv = aq;
+ mtd->priv = nor;
+
+ nor->read_reg = atmel_qspi_read_reg;
+ nor->write_reg = atmel_qspi_write_reg;
+ nor->read = atmel_qspi_read;
+ nor->write = atmel_qspi_write;
+ nor->erase = atmel_qspi_erase;
+
+ if (of_modalias_node(child, modalias, sizeof(modalias)) < 0) {
+ err = -ENODEV;
+ goto release_channel;
+ }
+
+ err = of_property_read_u32(child, "spi-max-frequency", &aq->clk_rate);
+ if (err < 0)
+ goto release_channel;
+
+ err = atmel_qspi_init(aq);
+ if (err)
+ goto release_channel;
+
+ nor->dev->of_node = child;
+ err = spi_nor_scan(nor, modalias, SPI_NOR_QUAD);
+ nor->dev->of_node = np;
+ if (err)
+ goto release_channel;
+
+ ppdata.of_node = child;
+ err = mtd_device_parse_register(mtd, NULL, &ppdata, NULL, 0);
+ if (err)
+ goto release_channel;
+
+ of_node_put(child);
+
+ return 0;
+
+release_channel:
+ if (aq->chan)
+ dma_release_channel(aq->chan);
+disable_clk:
+ clk_disable_unprepare(aq->clk);
+exit:
+ of_node_put(child);
+
+ return err;
+}
+
+static int atmel_qspi_remove(struct platform_device *pdev)
+{
+ struct atmel_qspi *aq = platform_get_drvdata(pdev);
+
+ mtd_device_unregister(&aq->mtd);
+ qspi_writel(aq, QSPI_CR, QSPI_CR_QSPIDIS);
+ if (aq->chan)
+ dma_release_channel(aq->chan);
+ clk_disable_unprepare(aq->clk);
+ return 0;
+}
+
+
+static const struct of_device_id atmel_qspi_dt_ids[] = {
+ { .compatible = "atmel,sama5d2-qspi" },
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, atmel_qspi_dt_ids);
+
+static struct platform_driver atmel_qspi_driver = {
+ .driver = {
+ .name = "atmel_qspi",
+ .of_match_table = atmel_qspi_dt_ids,
+ },
+ .probe = atmel_qspi_probe,
+ .remove = atmel_qspi_remove,
+};
+module_platform_driver(atmel_qspi_driver);
+
+MODULE_AUTHOR("Cyrille Pitchen <cyrille.pitchen@atmel.com>");
+MODULE_DESCRIPTION("Atmel QSPI Controller driver");
+MODULE_LICENSE("GPL v2");
--
1.8.2.2


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