[linux-next,v4,5/5] mtd: atmel-quadspi: add driver for Atmel QSPI controller

Message ID	bf368fc101f38db231131b69eff0863210f2b01c.1440410236.git.cyrille.pitchen@atmel.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <linux-spi-owner@kernel.org> From: Cyrille Pitchen <cyrille.pitchen@atmel.com> To: <nicolas.ferre@atmel.com>, <broonie@kernel.org>, <linux-spi@vger.kernel.org>, <dwmw2@infradead.org>, <computersforpeace@gmail.com>, <zajec5@gmail.com>, <beanhuo@micron.com>, <juhosg@openwrt.org>, <marex@denx.de>, <shijie.huang@intel.com>, <ben@decadent.org.uk> CC: <linux-kernel@vger.kernel.org>, <linux-arm-kernel@lists.infradead.org>, <devicetree@vger.kernel.org>, <robh+dt@kernel.org>, <pawel.moll@arm.com>, <mark.rutland@arm.com>, <ijc+devicetree@hellion.org.uk>, <galak@codeaurora.org>, <linux-mtd@lists.infradead.org>, Cyrille Pitchen <cyrille.pitchen@atmel.com> Subject: [PATCH linux-next v4 5/5] mtd: atmel-quadspi: add driver for Atmel QSPI controller Date: Mon, 24 Aug 2015 12:14:00 +0200 Message-ID: <bf368fc101f38db231131b69eff0863210f2b01c.1440410236.git.cyrille.pitchen@atmel.com> In-Reply-To: <cover.1440410236.git.cyrille.pitchen@atmel.com> References: <cover.1440410236.git.cyrille.pitchen@atmel.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-spi-owner@vger.kernel.org Precedence: bulk

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..ada6f95782e4 --- /dev/null +++ b/drivers/mtd/spi-nor/atmel-quadspi.c @@ -0,0 +1,876 @@ +/* + * 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 ifr_width; + u32 pending; + + struct mtd_info mtd; + struct spi_nor nor; + u32 clk_rate; + struct completion completion; + +#ifdef DEBUG + u8 last_instruction; +#endif +}; + +struct atmel_qspi_command { + u32 ifr_tfrtyp; + 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 macros */ +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); +} + +static inline u16 qspi_readw(struct atmel_qspi *aq, u32 reg) +{ + return readw_relaxed(aq->regs + reg); +} + +static inline void qspi_writew(struct atmel_qspi *aq, u32 reg, u16 value) +{ + writew_relaxed(value, aq->regs + reg); +} + +static inline u8 qspi_readb(struct atmel_qspi *aq, u32 reg) +{ + return readb_relaxed(aq->regs + reg); +} + +static inline void qspi_writeb(struct atmel_qspi *aq, u32 reg, u8 value) +{ + writeb_relaxed(value, aq->regs + reg); +} + + +#define QSPI_DMA_THRESHOLD 32 + +static void atmel_qspi_dma_callback(void *arg) +{ + struct completion *c = arg; + + complete(c); +} + +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; + struct completion completion; + 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; + } + + init_completion(&completion); + desc->callback = atmel_qspi_dma_callback; + desc->callback_param = &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(&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 (aq->ifr_width) { + 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 = aq->ifr_width | cmd->ifr_tfrtyp; + + /* 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; + /*break;*/ /* fallback to the 24bit 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 */ + init_completion(&aq->completion); + aq->pending = 0; + qspi_writel(aq, QSPI_IER, QSPI_SR_INSTRE); + if (!wait_for_completion_timeout(&aq->completion, + msecs_to_jiffies(1000))) + err = -ETIMEDOUT; + qspi_writel(aq, QSPI_IDR, QSPI_SR_INSTRE); + + return err; +} + +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; + + memset(&cmd, 0, sizeof(cmd)); + cmd.ifr_tfrtyp = QSPI_IFR_TFRTYP_TRSFR_READ; + cmd.enable.bits.instruction = 1; + cmd.enable.bits.data = 1; + cmd.instruction = opcode; + cmd.rx_buf = buf; + cmd.buf_len = len; + 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; + + memset(&cmd, 0, sizeof(cmd)); + cmd.ifr_tfrtyp = QSPI_IFR_TFRTYP_TRSFR_WRITE; + cmd.enable.bits.instruction = 1; + cmd.enable.bits.data = (buf != NULL && len > 0); + cmd.instruction = opcode; + cmd.tx_buf = buf; + cmd.buf_len = len; + 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.ifr_tfrtyp = QSPI_IFR_TFRTYP_TRSFR_WRITE_MEM; + 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_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; + + dev_dbg(nor->dev, "%dKiB at 0x%08x\n", + aq->mtd.erasesize / 1024, (u32)offs); + + memset(&cmd, 0, sizeof(cmd)); + cmd.ifr_tfrtyp = QSPI_IFR_TFRTYP_TRSFR_WRITE; + cmd.enable.bits.instruction = 1; + cmd.enable.bits.address = nor->addr_width; + cmd.instruction = nor->erase_opcode; + cmd.address = (u32)offs; + 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 err; + + memset(&cmd, 0, sizeof(cmd)); + cmd.ifr_tfrtyp = QSPI_IFR_TFRTYP_TRSFR_READ_MEM; + 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; + err = atmel_qspi_run_command(aq, &cmd); + if (err) + return err; + + *retlen += len; + return 0; +} + +static int atmel_qspi_set_protocol(struct spi_nor *nor, enum spi_protocol proto) +{ + struct atmel_qspi *aq = nor->priv; + + switch (proto) { + case SPI_PROTO_1_1_1: + aq->ifr_width = QSPI_IFR_WIDTH_SINGLE_BIT_SPI; + break; + case SPI_PROTO_1_1_2: + aq->ifr_width = QSPI_IFR_WIDTH_DUAL_OUTPUT; + break; + case SPI_PROTO_1_1_4: + aq->ifr_width = QSPI_IFR_WIDTH_QUAD_OUTPUT; + break; + case SPI_PROTO_1_2_2: + aq->ifr_width = QSPI_IFR_WIDTH_DUAL_IO; + break; + case SPI_PROTO_1_4_4: + aq->ifr_width = QSPI_IFR_WIDTH_QUAD_IO; + break; + case SPI_PROTO_2_2_2: + aq->ifr_width = QSPI_IFR_WIDTH_DUAL_CMD; + break; + case SPI_PROTO_4_4_4: + aq->ifr_width = QSPI_IFR_WIDTH_QUAD_CMD; + break; + default: + return -EINVAL; + } + + 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->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); + aq->pdev = pdev; + /* Start in Extended SPI (1-1-1) */ + aq->ifr_width = QSPI_IFR_WIDTH_SINGLE_BIT_SPI; + + /* 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; + nor->set_protocol = atmel_qspi_set_protocol; + + 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");

[linux-next,v4,5/5] mtd: atmel-quadspi: add driver for Atmel QSPI controller

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