From 0e6aae08e9ae7c2dc3c83bf6960d824feb14b706 Mon Sep 17 00:00:00 2001 From: Piotr Bugalski Date: Mon, 5 Nov 2018 11:36:24 +0100 Subject: spi: Add QuadSPI driver for Atmel SAMA5D2 Kernel contains QSPI driver strongly tied to MTD and nor-flash memory. New spi-mem interface allows usage also other memory types, especially much larger NAND with SPI interface. This driver works as SPI controller and is not related to MTD, however can work with NAND-flash or other peripherals using spi-mem interface. Suggested-by: Boris Brezillon Signed-off-by: Piotr Bugalski Signed-off-by: Mark Brown --- drivers/spi/Kconfig | 9 + drivers/spi/Makefile | 1 + drivers/spi/atmel-quadspi.c | 549 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 559 insertions(+) create mode 100644 drivers/spi/atmel-quadspi.c (limited to 'drivers/spi') diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 7d3a5c94727e..ca68ac63c6c3 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -91,6 +91,15 @@ config SPI_AT91_USART This selects a driver for the AT91 USART Controller as SPI Master, present on AT91 and SAMA5 SoC series. +config SPI_ATMEL_QUADSPI + tristate "Atmel Quad SPI Controller" + depends on ARCH_AT91 || (ARM && COMPILE_TEST) + depends on OF && HAS_IOMEM + help + This enables support for the Quad SPI controller in master mode. + This driver does not support generic SPI. The implementation only + supports spi-mem interface. + config SPI_AU1550 tristate "Au1550/Au1200/Au1300 SPI Controller" depends on MIPS_ALCHEMY diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 3575205c5c27..258917db3f56 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_SPI_LOOPBACK_TEST) += spi-loopback-test.o obj-$(CONFIG_SPI_ALTERA) += spi-altera.o obj-$(CONFIG_SPI_ARMADA_3700) += spi-armada-3700.o obj-$(CONFIG_SPI_ATMEL) += spi-atmel.o +obj-$(CONFIG_SPI_ATMEL_QUADSPI) += atmel-quadspi.o obj-$(CONFIG_SPI_AT91_USART) += spi-at91-usart.o obj-$(CONFIG_SPI_ATH79) += spi-ath79.o obj-$(CONFIG_SPI_AU1550) += spi-au1550.o diff --git a/drivers/spi/atmel-quadspi.c b/drivers/spi/atmel-quadspi.c new file mode 100644 index 000000000000..ddc712410812 --- /dev/null +++ b/drivers/spi/atmel-quadspi.c @@ -0,0 +1,549 @@ +/* + * Driver for Atmel QSPI Controller + * + * Copyright (C) 2015 Atmel Corporation + * Copyright (C) 2018 Cryptera A/S + * + * Author: Cyrille Pitchen + * Author: Piotr Bugalski + * + * 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 . + * + * This driver is based on drivers/mtd/spi-nor/fsl-quadspi.c from Freescale. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +/* 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_SMM 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) + +#define QSPI_SR_CMD_COMPLETED (QSPI_SR_INSTRE | QSPI_SR_CSR) + +/* 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; + struct clk *clk; + struct platform_device *pdev; + u32 pending; + struct completion cmd_completion; +}; + +struct qspi_mode { + u8 cmd_buswidth; + u8 addr_buswidth; + u8 data_buswidth; + u32 config; +}; + +static const struct qspi_mode sama5d2_qspi_modes[] = { + { 1, 1, 1, QSPI_IFR_WIDTH_SINGLE_BIT_SPI }, + { 1, 1, 2, QSPI_IFR_WIDTH_DUAL_OUTPUT }, + { 1, 1, 4, QSPI_IFR_WIDTH_QUAD_OUTPUT }, + { 1, 2, 2, QSPI_IFR_WIDTH_DUAL_IO }, + { 1, 4, 4, QSPI_IFR_WIDTH_QUAD_IO }, + { 2, 2, 2, QSPI_IFR_WIDTH_DUAL_CMD }, + { 4, 4, 4, QSPI_IFR_WIDTH_QUAD_CMD }, +}; + +/* 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); +} + +static inline bool is_compatible(const struct spi_mem_op *op, + const struct qspi_mode *mode) +{ + if (op->cmd.buswidth != mode->cmd_buswidth) + return false; + + if (op->addr.nbytes && op->addr.buswidth != mode->addr_buswidth) + return false; + + if (op->data.nbytes && op->data.buswidth != mode->data_buswidth) + return false; + + return true; +} + +static int find_mode(const struct spi_mem_op *op) +{ + u32 i; + + for (i = 0; i < ARRAY_SIZE(sama5d2_qspi_modes); i++) + if (is_compatible(op, &sama5d2_qspi_modes[i])) + return i; + + return -1; +} + +static bool atmel_qspi_supports_op(struct spi_mem *mem, + const struct spi_mem_op *op) +{ + if (find_mode(op) < 0) + return false; + + /* special case not supported by hardware */ + if (op->addr.nbytes == 2 && op->cmd.buswidth != op->addr.buswidth && + op->dummy.nbytes == 0) + return false; + + return true; +} + +static int atmel_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op) +{ + struct atmel_qspi *aq = spi_controller_get_devdata(mem->spi->master); + int mode; + u32 dummy_cycles = 0; + u32 iar, icr, ifr, sr; + int err = 0; + + iar = 0; + icr = QSPI_ICR_INST(op->cmd.opcode); + ifr = QSPI_IFR_INSTEN; + + qspi_writel(aq, QSPI_MR, QSPI_MR_SMM); + + mode = find_mode(op); + if (mode < 0) + return -ENOTSUPP; + + ifr |= sama5d2_qspi_modes[mode].config; + + if (op->dummy.buswidth && op->dummy.nbytes) + dummy_cycles = op->dummy.nbytes * 8 / op->dummy.buswidth; + + if (op->addr.buswidth) { + switch (op->addr.nbytes) { + case 0: + break; + case 1: + ifr |= QSPI_IFR_OPTEN | QSPI_IFR_OPTL_8BIT; + icr |= QSPI_ICR_OPT(op->addr.val & 0xff); + break; + case 2: + if (dummy_cycles < 8 / op->addr.buswidth) { + ifr &= ~QSPI_IFR_INSTEN; + ifr |= QSPI_IFR_ADDREN; + iar = (op->cmd.opcode << 16) | + (op->addr.val & 0xffff); + } else { + ifr |= QSPI_IFR_ADDREN; + iar = (op->addr.val << 8) & 0xffffff; + dummy_cycles -= 8 / op->addr.buswidth; + } + break; + case 3: + ifr |= QSPI_IFR_ADDREN; + iar = op->addr.val & 0xffffff; + break; + case 4: + ifr |= QSPI_IFR_ADDREN | QSPI_IFR_ADDRL; + iar = op->addr.val & 0x7ffffff; + break; + default: + return -ENOTSUPP; + } + } + + /* Set number of dummy cycles */ + if (dummy_cycles) + ifr |= QSPI_IFR_NBDUM(dummy_cycles); + + /* Set data enable */ + if (op->data.nbytes) + ifr |= QSPI_IFR_DATAEN; + + if (op->data.dir == SPI_MEM_DATA_IN && op->data.nbytes) + ifr |= QSPI_IFR_TFRTYP_TRSFR_READ; + else + ifr |= QSPI_IFR_TFRTYP_TRSFR_WRITE; + + /* Clear pending interrupts */ + (void)qspi_readl(aq, QSPI_SR); + + /* Set QSPI Instruction Frame registers */ + 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 (op->data.nbytes) { + /* Dummy read of QSPI_IFR to synchronize APB and AHB accesses */ + (void)qspi_readl(aq, QSPI_IFR); + + /* Send/Receive data */ + if (op->data.dir == SPI_MEM_DATA_IN) + _memcpy_fromio(op->data.buf.in, + aq->mem + iar, op->data.nbytes); + else + _memcpy_toio(aq->mem + iar, + op->data.buf.out, op->data.nbytes); + + /* Release the chip-select */ + qspi_writel(aq, QSPI_CR, QSPI_CR_LASTXFER); + } + + /* Poll INSTRuction End status */ + sr = qspi_readl(aq, QSPI_SR); + if ((sr & QSPI_SR_CMD_COMPLETED) == QSPI_SR_CMD_COMPLETED) + return err; + + /* Wait for INSTRuction End interrupt */ + reinit_completion(&aq->cmd_completion); + aq->pending = sr & QSPI_SR_CMD_COMPLETED; + qspi_writel(aq, QSPI_IER, QSPI_SR_CMD_COMPLETED); + if (!wait_for_completion_timeout(&aq->cmd_completion, + msecs_to_jiffies(1000))) + err = -ETIMEDOUT; + qspi_writel(aq, QSPI_IDR, QSPI_SR_CMD_COMPLETED); + + return err; +} + +const char *atmel_qspi_get_name(struct spi_mem *spimem) +{ + return dev_name(spimem->spi->dev.parent); +} + +static const struct spi_controller_mem_ops atmel_qspi_mem_ops = { + .supports_op = atmel_qspi_supports_op, + .exec_op = atmel_qspi_exec_op, + .get_name = atmel_qspi_get_name +}; + +static int atmel_qspi_setup(struct spi_device *spi) +{ + struct spi_controller *ctrl = spi->master; + struct atmel_qspi *aq = spi_controller_get_devdata(ctrl); + unsigned long src_rate; + u32 scr, scbr; + + if (ctrl->busy) + return -EBUSY; + + if (!spi->max_speed_hz) + return -EINVAL; + + src_rate = clk_get_rate(aq->clk); + if (!src_rate) + return -EINVAL; + + /* Compute the QSPI baudrate */ + scbr = DIV_ROUND_UP(src_rate, spi->max_speed_hz); + if (scbr > 0) + scbr--; + + scr = QSPI_SCR_SCBR(scbr); + qspi_writel(aq, QSPI_SCR, scr); + + return 0; +} + +static int atmel_qspi_init(struct atmel_qspi *aq) +{ + /* Reset the QSPI controller */ + qspi_writel(aq, QSPI_CR, QSPI_CR_SWRST); + + /* 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 ((aq->pending & QSPI_SR_CMD_COMPLETED) == QSPI_SR_CMD_COMPLETED) + complete(&aq->cmd_completion); + + return IRQ_HANDLED; +} + +static int atmel_qspi_probe(struct platform_device *pdev) +{ + struct spi_controller *ctrl; + struct atmel_qspi *aq; + struct resource *res; + int irq, err = 0; + + ctrl = spi_alloc_master(&pdev->dev, sizeof(*aq)); + if (!ctrl) + return -ENOMEM; + + ctrl->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_DUAL | SPI_TX_QUAD; + ctrl->setup = atmel_qspi_setup; + ctrl->bus_num = -1; + ctrl->mem_ops = &atmel_qspi_mem_ops; + ctrl->num_chipselect = 1; + ctrl->dev.of_node = pdev->dev.of_node; + platform_set_drvdata(pdev, ctrl); + + aq = spi_controller_get_devdata(ctrl); + + init_completion(&aq->cmd_completion); + aq->pdev = pdev; + + /* Map the registers */ + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_base"); + 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_byname(pdev, IORESOURCE_MEM, "qspi_mmap"); + 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->mem); + goto exit; + } + + /* 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; + + err = atmel_qspi_init(aq); + if (err) + goto disable_clk; + + err = spi_register_controller(ctrl); + if (err) + goto disable_clk; + + return 0; + +disable_clk: + clk_disable_unprepare(aq->clk); +exit: + spi_controller_put(ctrl); + + return err; +} + +static int atmel_qspi_remove(struct platform_device *pdev) +{ + struct spi_controller *ctrl = platform_get_drvdata(pdev); + struct atmel_qspi *aq = spi_controller_get_devdata(ctrl); + + spi_unregister_controller(ctrl); + qspi_writel(aq, QSPI_CR, QSPI_CR_QSPIDIS); + clk_disable_unprepare(aq->clk); + return 0; +} + +static int __maybe_unused atmel_qspi_suspend(struct device *dev) +{ + struct atmel_qspi *aq = dev_get_drvdata(dev); + + clk_disable_unprepare(aq->clk); + + return 0; +} + +static int __maybe_unused atmel_qspi_resume(struct device *dev) +{ + struct atmel_qspi *aq = dev_get_drvdata(dev); + + clk_prepare_enable(aq->clk); + + return atmel_qspi_init(aq); +} + +static SIMPLE_DEV_PM_OPS(atmel_qspi_pm_ops, atmel_qspi_suspend, + atmel_qspi_resume); + +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, + .pm = &atmel_qspi_pm_ops, + }, + .probe = atmel_qspi_probe, + .remove = atmel_qspi_remove, +}; +module_platform_driver(atmel_qspi_driver); + +MODULE_AUTHOR("Cyrille Pitchen "); +MODULE_AUTHOR("Piotr Bugalski data.nbytes to know whether there will be data transferred for a specific operation is this not possible. Add SPI_MEM_NO_DATA to the spi_mem_data_dir enum so that we can base our checks on op->data.dir instead of op->data.nbytes. Signed-off-by: Boris Brezillon Reviewed-by: Miquel Raynal Signed-off-by: Mark Brown --- drivers/spi/spi-mem.c | 2 +- include/linux/spi/spi-mem.h | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/spi') diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c index 62a7b80801d2..967f581bca4f 100644 --- a/drivers/spi/spi-mem.c +++ b/drivers/spi/spi-mem.c @@ -142,7 +142,7 @@ static bool spi_mem_default_supports_op(struct spi_mem *mem, spi_check_buswidth_req(mem, op->dummy.buswidth, true)) return false; - if (op->data.nbytes && + if (op->data.dir != SPI_MEM_NO_DATA && spi_check_buswidth_req(mem, op->data.buswidth, op->data.dir == SPI_MEM_DATA_OUT)) return false; diff --git a/include/linux/spi/spi-mem.h b/include/linux/spi/spi-mem.h index 867839cc69a7..250b6f5c47c2 100644 --- a/include/linux/spi/spi-mem.h +++ b/include/linux/spi/spi-mem.h @@ -57,10 +57,12 @@ /** * enum spi_mem_data_dir - describes the direction of a SPI memory data * transfer from the controller perspective + * @SPI_MEM_NO_DATA: no data transferred * @SPI_MEM_DATA_IN: data coming from the SPI memory * @SPI_MEM_DATA_OUT: data sent to the SPI memory */ enum spi_mem_data_dir { + SPI_MEM_NO_DATA, SPI_MEM_DATA_IN, SPI_MEM_DATA_OUT, }; -- cgit v1.2.3 From f86c24f4795303e4024bc113196de32782f6ccb5 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Tue, 6 Nov 2018 17:05:32 +0100 Subject: spi: spi-mem: Split spi_mem_exec_op() code The logic surrounding the ->exec_op() call applies to direct mapping accessors. Move this code to separate functions to avoid duplicating code. Signed-off-by: Boris Brezillon Reviewed-by: Miquel Raynal Signed-off-by: Mark Brown --- drivers/spi/spi-mem.c | 63 ++++++++++++++++++++++++++++++++++----------------- 1 file changed, 42 insertions(+), 21 deletions(-) (limited to 'drivers/spi') diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c index 967f581bca4f..7916e655afc8 100644 --- a/drivers/spi/spi-mem.c +++ b/drivers/spi/spi-mem.c @@ -213,6 +213,44 @@ bool spi_mem_supports_op(struct spi_mem *mem, const struct spi_mem_op *op) } EXPORT_SYMBOL_GPL(spi_mem_supports_op); +static int spi_mem_access_start(struct spi_mem *mem) +{ + struct spi_controller *ctlr = mem->spi->controller; + + /* + * Flush the message queue before executing our SPI memory + * operation to prevent preemption of regular SPI transfers. + */ + spi_flush_queue(ctlr); + + if (ctlr->auto_runtime_pm) { + int ret; + + ret = pm_runtime_get_sync(ctlr->dev.parent); + if (ret < 0) { + dev_err(&ctlr->dev, "Failed to power device: %d\n", + ret); + return ret; + } + } + + mutex_lock(&ctlr->bus_lock_mutex); + mutex_lock(&ctlr->io_mutex); + + return 0; +} + +static void spi_mem_access_end(struct spi_mem *mem) +{ + struct spi_controller *ctlr = mem->spi->controller; + + mutex_unlock(&ctlr->io_mutex); + mutex_unlock(&ctlr->bus_lock_mutex); + + if (ctlr->auto_runtime_pm) + pm_runtime_put(ctlr->dev.parent); +} + /** * spi_mem_exec_op() - Execute a memory operation * @mem: the SPI memory @@ -242,30 +280,13 @@ int spi_mem_exec_op(struct spi_mem *mem, const struct spi_mem_op *op) return -ENOTSUPP; if (ctlr->mem_ops) { - /* - * Flush the message queue before executing our SPI memory - * operation to prevent preemption of regular SPI transfers. - */ - spi_flush_queue(ctlr); - - if (ctlr->auto_runtime_pm) { - ret = pm_runtime_get_sync(ctlr->dev.parent); - if (ret < 0) { - dev_err(&ctlr->dev, - "Failed to power device: %d\n", - ret); - return ret; - } - } + ret = spi_mem_access_start(mem); + if (ret) + return ret; - mutex_lock(&ctlr->bus_lock_mutex); - mutex_lock(&ctlr->io_mutex); ret = ctlr->mem_ops->exec_op(mem, op); - mutex_unlock(&ctlr->io_mutex); - mutex_unlock(&ctlr->bus_lock_mutex); - if (ctlr->auto_runtime_pm) - pm_runtime_put(ctlr->dev.parent); + spi_mem_access_end(mem); /* * Some controllers only optimize specific paths (typically the -- cgit v1.2.3 From aa167f3fed0c37e0e4c707d4331d827661f46644 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Tue, 6 Nov 2018 17:05:33 +0100 Subject: spi: spi-mem: Add a new API to support direct mapping Most modern SPI controllers can directly map a SPI memory (or a portion of the SPI memory) in the CPU address space. Most of the time this brings significant performance improvements as it automates the whole process of sending SPI memory operations every time a new region is accessed. This new API allows SPI memory drivers to create direct mappings and then use them to access the memory instead of using spi_mem_exec_op(). Signed-off-by: Boris Brezillon Reviewed-by: Miquel Raynal Signed-off-by: Mark Brown --- drivers/spi/spi-mem.c | 204 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/spi/spi-mem.h | 80 +++++++++++++++++ 2 files changed, 284 insertions(+) (limited to 'drivers/spi') diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c index 7916e655afc8..b12a7974b665 100644 --- a/drivers/spi/spi-mem.c +++ b/drivers/spi/spi-mem.c @@ -432,6 +432,210 @@ int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op) } EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size); +static ssize_t spi_mem_no_dirmap_read(struct spi_mem_dirmap_desc *desc, + u64 offs, size_t len, void *buf) +{ + struct spi_mem_op op = desc->info.op_tmpl; + int ret; + + op.addr.val = desc->info.offset + offs; + op.data.buf.in = buf; + op.data.nbytes = len; + ret = spi_mem_adjust_op_size(desc->mem, &op); + if (ret) + return ret; + + ret = spi_mem_exec_op(desc->mem, &op); + if (ret) + return ret; + + return op.data.nbytes; +} + +static ssize_t spi_mem_no_dirmap_write(struct spi_mem_dirmap_desc *desc, + u64 offs, size_t len, const void *buf) +{ + struct spi_mem_op op = desc->info.op_tmpl; + int ret; + + op.addr.val = desc->info.offset + offs; + op.data.buf.out = buf; + op.data.nbytes = len; + ret = spi_mem_adjust_op_size(desc->mem, &op); + if (ret) + return ret; + + ret = spi_mem_exec_op(desc->mem, &op); + if (ret) + return ret; + + return op.data.nbytes; +} + +/** + * spi_mem_dirmap_create() - Create a direct mapping descriptor + * @mem: SPI mem device this direct mapping should be created for + * @info: direct mapping information + * + * This function is creating a direct mapping descriptor which can then be used + * to access the memory using spi_mem_dirmap_read() or spi_mem_dirmap_write(). + * If the SPI controller driver does not support direct mapping, this function + * fallback to an implementation using spi_mem_exec_op(), so that the caller + * doesn't have to bother implementing a fallback on his own. + * + * Return: a valid pointer in case of success, and ERR_PTR() otherwise. + */ +struct spi_mem_dirmap_desc * +spi_mem_dirmap_create(struct spi_mem *mem, + const struct spi_mem_dirmap_info *info) +{ + struct spi_controller *ctlr = mem->spi->controller; + struct spi_mem_dirmap_desc *desc; + int ret = -ENOTSUPP; + + /* Make sure the number of address cycles is between 1 and 8 bytes. */ + if (!info->op_tmpl.addr.nbytes || info->op_tmpl.addr.nbytes > 8) + return ERR_PTR(-EINVAL); + + /* data.dir should either be SPI_MEM_DATA_IN or SPI_MEM_DATA_OUT. */ + if (info->op_tmpl.data.dir == SPI_MEM_NO_DATA) + return ERR_PTR(-EINVAL); + + desc = kzalloc(sizeof(*desc), GFP_KERNEL); + if (!desc) + return ERR_PTR(-ENOMEM); + + desc->mem = mem; + desc->info = *info; + if (ctlr->mem_ops && ctlr->mem_ops->dirmap_create) + ret = ctlr->mem_ops->dirmap_create(desc); + + if (ret) { + desc->nodirmap = true; + if (!spi_mem_supports_op(desc->mem, &desc->info.op_tmpl)) + ret = -ENOTSUPP; + else + ret = 0; + } + + if (ret) { + kfree(desc); + return ERR_PTR(ret); + } + + return desc; +} +EXPORT_SYMBOL_GPL(spi_mem_dirmap_create); + +/** + * spi_mem_dirmap_destroy() - Destroy a direct mapping descriptor + * @desc: the direct mapping descriptor to destroy + * @info: direct mapping information + * + * This function destroys a direct mapping descriptor previously created by + * spi_mem_dirmap_create(). + */ +void spi_mem_dirmap_destroy(struct spi_mem_dirmap_desc *desc) +{ + struct spi_controller *ctlr = desc->mem->spi->controller; + + if (!desc->nodirmap && ctlr->mem_ops && ctlr->mem_ops->dirmap_destroy) + ctlr->mem_ops->dirmap_destroy(desc); +} +EXPORT_SYMBOL_GPL(spi_mem_dirmap_destroy); + +/** + * spi_mem_dirmap_dirmap_read() - Read data through a direct mapping + * @desc: direct mapping descriptor + * @offs: offset to start reading from. Note that this is not an absolute + * offset, but the offset within the direct mapping which already has + * its own offset + * @len: length in bytes + * @buf: destination buffer. This buffer must be DMA-able + * + * This function reads data from a memory device using a direct mapping + * previously instantiated with spi_mem_dirmap_create(). + * + * Return: the amount of data read from the memory device or a negative error + * code. Note that the returned size might be smaller than @len, and the caller + * is responsible for calling spi_mem_dirmap_read() again when that happens. + */ +ssize_t spi_mem_dirmap_read(struct spi_mem_dirmap_desc *desc, + u64 offs, size_t len, void *buf) +{ + struct spi_controller *ctlr = desc->mem->spi->controller; + ssize_t ret; + + if (desc->info.op_tmpl.data.dir != SPI_MEM_DATA_IN) + return -EINVAL; + + if (!len) + return 0; + + if (desc->nodirmap) { + ret = spi_mem_no_dirmap_read(desc, offs, len, buf); + } else if (ctlr->mem_ops && ctlr->mem_ops->dirmap_read) { + ret = spi_mem_access_start(desc->mem); + if (ret) + return ret; + + ret = ctlr->mem_ops->dirmap_read(desc, offs, len, buf); + + spi_mem_access_end(desc->mem); + } else { + ret = -ENOTSUPP; + } + + return ret; +} +EXPORT_SYMBOL_GPL(spi_mem_dirmap_read); + +/** + * spi_mem_dirmap_dirmap_write() - Write data through a direct mapping + * @desc: direct mapping descriptor + * @offs: offset to start writing from. Note that this is not an absolute + * offset, but the offset within the direct mapping which already has + * its own offset + * @len: length in bytes + * @buf: source buffer. This buffer must be DMA-able + * + * This function writes data to a memory device using a direct mapping + * previously instantiated with spi_mem_dirmap_create(). + * + * Return: the amount of data written to the memory device or a negative error + * code. Note that the returned size might be smaller than @len, and the caller + * is responsible for calling spi_mem_dirmap_write() again when that happens. + */ +ssize_t spi_mem_dirmap_write(struct spi_mem_dirmap_desc *desc, + u64 offs, size_t len, const void *buf) +{ + struct spi_controller *ctlr = desc->mem->spi->controller; + ssize_t ret; + + if (desc->info.op_tmpl.data.dir != SPI_MEM_DATA_OUT) + return -EINVAL; + + if (!len) + return 0; + + if (desc->nodirmap) { + ret = spi_mem_no_dirmap_write(desc, offs, len, buf); + } else if (ctlr->mem_ops && ctlr->mem_ops->dirmap_write) { + ret = spi_mem_access_start(desc->mem); + if (ret) + return ret; + + ret = ctlr->mem_ops->dirmap_write(desc, offs, len, buf); + + spi_mem_access_end(desc->mem); + } else { + ret = -ENOTSUPP; + } + + return ret; +} +EXPORT_SYMBOL_GPL(spi_mem_dirmap_write); + static inline struct spi_mem_driver *to_spi_mem_drv(struct device_driver *drv) { return container_of(drv, struct spi_mem_driver, spidrv.driver); diff --git a/include/linux/spi/spi-mem.h b/include/linux/spi/spi-mem.h index 250b6f5c47c2..3fe24500c5ee 100644 --- a/include/linux/spi/spi-mem.h +++ b/include/linux/spi/spi-mem.h @@ -124,6 +124,49 @@ struct spi_mem_op { .data = __data, \ } +/** + * struct spi_mem_dirmap_info - Direct mapping information + * @op_tmpl: operation template that should be used by the direct mapping when + * the memory device is accessed + * @offset: absolute offset this direct mapping is pointing to + * @length: length in byte of this direct mapping + * + * These information are used by the controller specific implementation to know + * the portion of memory that is directly mapped and the spi_mem_op that should + * be used to access the device. + * A direct mapping is only valid for one direction (read or write) and this + * direction is directly encoded in the ->op_tmpl.data.dir field. + */ +struct spi_mem_dirmap_info { + struct spi_mem_op op_tmpl; + u64 offset; + u64 length; +}; + +/** + * struct spi_mem_dirmap_desc - Direct mapping descriptor + * @mem: the SPI memory device this direct mapping is attached to + * @info: information passed at direct mapping creation time + * @nodirmap: set to 1 if the SPI controller does not implement + * ->mem_ops->dirmap_create() or when this function returned an + * error. If @nodirmap is true, all spi_mem_dirmap_{read,write}() + * calls will use spi_mem_exec_op() to access the memory. This is a + * degraded mode that allows spi_mem drivers to use the same code + * no matter whether the controller supports direct mapping or not + * @priv: field pointing to controller specific data + * + * Common part of a direct mapping descriptor. This object is created by + * spi_mem_dirmap_create() and controller implementation of ->create_dirmap() + * can create/attach direct mapping resources to the descriptor in the ->priv + * field. + */ +struct spi_mem_dirmap_desc { + struct spi_mem *mem; + struct spi_mem_dirmap_info info; + unsigned int nodirmap; + void *priv; +}; + /** * struct spi_mem - describes a SPI memory device * @spi: the underlying SPI device @@ -179,10 +222,32 @@ static inline void *spi_mem_get_drvdata(struct spi_mem *mem) * Note that if the implementation of this function allocates memory * dynamically, then it should do so with devm_xxx(), as we don't * have a ->free_name() function. + * @dirmap_create: create a direct mapping descriptor that can later be used to + * access the memory device. This method is optional + * @dirmap_destroy: destroy a memory descriptor previous created by + * ->dirmap_create() + * @dirmap_read: read data from the memory device using the direct mapping + * created by ->dirmap_create(). The function can return less + * data than requested (for example when the request is crossing + * the currently mapped area), and the caller of + * spi_mem_dirmap_read() is responsible for calling it again in + * this case. + * @dirmap_write: write data to the memory device using the direct mapping + * created by ->dirmap_create(). The function can return less + * data than requested (for example when the request is crossing + * the currently mapped area), and the caller of + * spi_mem_dirmap_write() is responsible for calling it again in + * this case. * * This interface should be implemented by SPI controllers providing an * high-level interface to execute SPI memory operation, which is usually the * case for QSPI controllers. + * + * Note on ->dirmap_{read,write}(): drivers should avoid accessing the direct + * mapping from the CPU because doing that can stall the CPU waiting for the + * SPI mem transaction to finish, and this will make real-time maintainers + * unhappy and might make your system less reactive. Instead, drivers should + * use DMA to access this direct mapping. */ struct spi_controller_mem_ops { int (*adjust_op_size)(struct spi_mem *mem, struct spi_mem_op *op); @@ -191,6 +256,12 @@ struct spi_controller_mem_ops { int (*exec_op)(struct spi_mem *mem, const struct spi_mem_op *op); const char *(*get_name)(struct spi_mem *mem); + int (*dirmap_create)(struct spi_mem_dirmap_desc *desc); + void (*dirmap_destroy)(struct spi_mem_dirmap_desc *desc); + ssize_t (*dirmap_read)(struct spi_mem_dirmap_desc *desc, + u64 offs, size_t len, void *buf); + ssize_t (*dirmap_write)(struct spi_mem_dirmap_desc *desc, + u64 offs, size_t len, const void *buf); }; /** @@ -251,6 +322,15 @@ int spi_mem_exec_op(struct spi_mem *mem, const char *spi_mem_get_name(struct spi_mem *mem); +struct spi_mem_dirmap_desc * +spi_mem_dirmap_create(struct spi_mem *mem, + const struct spi_mem_dirmap_info *info); +void spi_mem_dirmap_destroy(struct spi_mem_dirmap_desc *desc); +ssize_t spi_mem_dirmap_read(struct spi_mem_dirmap_desc *desc, + u64 offs, size_t len, void *buf); +ssize_t spi_mem_dirmap_write(struct spi_mem_dirmap_desc *desc, + u64 offs, size_t len, const void *buf); + int spi_mem_driver_register_with_owner(struct spi_mem_driver *drv, struct module *owner); -- cgit v1.2.3 From 2a9d92fb3a1282a4659f1bb6d5684018846537b7 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 10 Dec 2018 21:38:16 +0100 Subject: mtd: atmel-quadspi: disallow building on ebsa110 I ran into a link-time error with the atmel-quadspi driver on the EBSA110 platform: drivers/mtd/built-in.o: In function `atmel_qspi_run_command': :(.text+0x1ee3c): undefined reference to `_memcpy_toio' :(.text+0x1ee48): undefined reference to `_memcpy_fromio' The problem is that _memcpy_toio/_memcpy_fromio are not available on that platform, and we have to prevent building the driver there. In case we want to backport this to older kernels: between linux-4.8 and linux-4.20, the Kconfig entry was in drivers/mtd/spi-nor/Kconfig but had the same problem. Link: https://lore.kernel.org/patchwork/patch/812860/ Fixes: 161aaab8a067 ("mtd: atmel-quadspi: add driver for Atmel QSPI controller") Signed-off-by: Arnd Bergmann Reviewed-by: Boris Brezillon Signed-off-by: Mark Brown Cc: stable@vger.kernel.org --- drivers/spi/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/spi') diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index ca68ac63c6c3..3135f80ec853 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -93,7 +93,7 @@ config SPI_AT91_USART config SPI_ATMEL_QUADSPI tristate "Atmel Quad SPI Controller" - depends on ARCH_AT91 || (ARM && COMPILE_TEST) + depends on ARCH_AT91 || (ARM && COMPILE_TEST && !ARCH_EBSA110) depends on OF && HAS_IOMEM help This enables support for the Quad SPI controller in master mode. -- cgit v1.2.3