diff options
Diffstat (limited to 'drivers/mtd/spi-nor/stm32-quadspi.c')
-rw-r--r-- | drivers/mtd/spi-nor/stm32-quadspi.c | 693 |
1 files changed, 693 insertions, 0 deletions
diff --git a/drivers/mtd/spi-nor/stm32-quadspi.c b/drivers/mtd/spi-nor/stm32-quadspi.c new file mode 100644 index 0000000..ae45f81 --- /dev/null +++ b/drivers/mtd/spi-nor/stm32-quadspi.c @@ -0,0 +1,693 @@ +/* + * stm32_quadspi.c + * + * Copyright (C) 2017, Ludovic Barre + * + * License terms: GNU General Public License (GPL), version 2 + */ +#include <linux/clk.h> +#include <linux/errno.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/partitions.h> +#include <linux/mtd/spi-nor.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/reset.h> + +#define QUADSPI_CR 0x00 +#define CR_EN BIT(0) +#define CR_ABORT BIT(1) +#define CR_DMAEN BIT(2) +#define CR_TCEN BIT(3) +#define CR_SSHIFT BIT(4) +#define CR_DFM BIT(6) +#define CR_FSEL BIT(7) +#define CR_FTHRES_SHIFT 8 +#define CR_FTHRES_MASK GENMASK(12, 8) +#define CR_FTHRES(n) (((n) << CR_FTHRES_SHIFT) & CR_FTHRES_MASK) +#define CR_TEIE BIT(16) +#define CR_TCIE BIT(17) +#define CR_FTIE BIT(18) +#define CR_SMIE BIT(19) +#define CR_TOIE BIT(20) +#define CR_PRESC_SHIFT 24 +#define CR_PRESC_MASK GENMASK(31, 24) +#define CR_PRESC(n) (((n) << CR_PRESC_SHIFT) & CR_PRESC_MASK) + +#define QUADSPI_DCR 0x04 +#define DCR_CSHT_SHIFT 8 +#define DCR_CSHT_MASK GENMASK(10, 8) +#define DCR_CSHT(n) (((n) << DCR_CSHT_SHIFT) & DCR_CSHT_MASK) +#define DCR_FSIZE_SHIFT 16 +#define DCR_FSIZE_MASK GENMASK(20, 16) +#define DCR_FSIZE(n) (((n) << DCR_FSIZE_SHIFT) & DCR_FSIZE_MASK) + +#define QUADSPI_SR 0x08 +#define SR_TEF BIT(0) +#define SR_TCF BIT(1) +#define SR_FTF BIT(2) +#define SR_SMF BIT(3) +#define SR_TOF BIT(4) +#define SR_BUSY BIT(5) +#define SR_FLEVEL_SHIFT 8 +#define SR_FLEVEL_MASK GENMASK(13, 8) + +#define QUADSPI_FCR 0x0c +#define FCR_CTCF BIT(1) + +#define QUADSPI_DLR 0x10 + +#define QUADSPI_CCR 0x14 +#define CCR_INST_SHIFT 0 +#define CCR_INST_MASK GENMASK(7, 0) +#define CCR_INST(n) (((n) << CCR_INST_SHIFT) & CCR_INST_MASK) +#define CCR_IMODE_NONE (0U << 8) +#define CCR_IMODE_1 (1U << 8) +#define CCR_IMODE_2 (2U << 8) +#define CCR_IMODE_4 (3U << 8) +#define CCR_ADMODE_NONE (0U << 10) +#define CCR_ADMODE_1 (1U << 10) +#define CCR_ADMODE_2 (2U << 10) +#define CCR_ADMODE_4 (3U << 10) +#define CCR_ADSIZE_SHIFT 12 +#define CCR_ADSIZE_MASK GENMASK(13, 12) +#define CCR_ADSIZE(n) (((n) << CCR_ADSIZE_SHIFT) & CCR_ADSIZE_MASK) +#define CCR_ABMODE_NONE (0U << 14) +#define CCR_ABMODE_1 (1U << 14) +#define CCR_ABMODE_2 (2U << 14) +#define CCR_ABMODE_4 (3U << 14) +#define CCR_ABSIZE_8 (0U << 16) +#define CCR_ABSIZE_16 (1U << 16) +#define CCR_ABSIZE_24 (2U << 16) +#define CCR_ABSIZE_32 (3U << 16) +#define CCR_DCYC_SHIFT 18 +#define CCR_DCYC_MASK GENMASK(22, 18) +#define CCR_DCYC(n) (((n) << CCR_DCYC_SHIFT) & CCR_DCYC_MASK) +#define CCR_DMODE_NONE (0U << 24) +#define CCR_DMODE_1 (1U << 24) +#define CCR_DMODE_2 (2U << 24) +#define CCR_DMODE_4 (3U << 24) +#define CCR_FMODE_INDW (0U << 26) +#define CCR_FMODE_INDR (1U << 26) +#define CCR_FMODE_APM (2U << 26) +#define CCR_FMODE_MM (3U << 26) + +#define QUADSPI_AR 0x18 +#define QUADSPI_ABR 0x1c +#define QUADSPI_DR 0x20 +#define QUADSPI_PSMKR 0x24 +#define QUADSPI_PSMAR 0x28 +#define QUADSPI_PIR 0x2c +#define QUADSPI_LPTR 0x30 +#define LPTR_DFT_TIMEOUT 0x10 + +#define FSIZE_VAL(size) (__fls(size) - 1) + +#define STM32_MAX_MMAP_SZ SZ_256M +#define STM32_MAX_NORCHIP 2 + +#define STM32_QSPI_FIFO_TIMEOUT_US 30000 +#define STM32_QSPI_BUSY_TIMEOUT_US 100000 + +struct stm32_qspi_flash { + struct spi_nor nor; + struct stm32_qspi *qspi; + u32 cs; + u32 fsize; + u32 presc; + u32 read_mode; + bool registered; +}; + +struct stm32_qspi { + struct device *dev; + void __iomem *io_base; + void __iomem *mm_base; + resource_size_t mm_size; + u32 nor_num; + struct clk *clk; + u32 clk_rate; + struct stm32_qspi_flash flash[STM32_MAX_NORCHIP]; + struct completion cmd_completion; + + /* + * to protect device configuration, could be different between + * 2 flash access (bk1, bk2) + */ + struct mutex lock; +}; + +struct stm32_qspi_cmd { + u8 addr_width; + u8 dummy; + bool tx_data; + u8 opcode; + u32 framemode; + u32 qspimode; + u32 addr; + size_t len; + void *buf; +}; + +static int stm32_qspi_wait_cmd(struct stm32_qspi *qspi) +{ + u32 cr; + int err = 0; + + if (readl_relaxed(qspi->io_base + QUADSPI_SR) & SR_TCF) + return 0; + + reinit_completion(&qspi->cmd_completion); + cr = readl_relaxed(qspi->io_base + QUADSPI_CR); + writel_relaxed(cr | CR_TCIE, qspi->io_base + QUADSPI_CR); + + if (!wait_for_completion_interruptible_timeout(&qspi->cmd_completion, + msecs_to_jiffies(1000))) + err = -ETIMEDOUT; + + writel_relaxed(cr, qspi->io_base + QUADSPI_CR); + return err; +} + +static int stm32_qspi_wait_nobusy(struct stm32_qspi *qspi) +{ + u32 sr; + + return readl_relaxed_poll_timeout(qspi->io_base + QUADSPI_SR, sr, + !(sr & SR_BUSY), 10, + STM32_QSPI_BUSY_TIMEOUT_US); +} + +static void stm32_qspi_set_framemode(struct spi_nor *nor, + struct stm32_qspi_cmd *cmd, bool read) +{ + u32 dmode = CCR_DMODE_1; + + cmd->framemode = CCR_IMODE_1; + + if (read) { + switch (nor->flash_read) { + case SPI_NOR_NORMAL: + case SPI_NOR_FAST: + dmode = CCR_DMODE_1; + break; + case SPI_NOR_DUAL: + dmode = CCR_DMODE_2; + break; + case SPI_NOR_QUAD: + dmode = CCR_DMODE_4; + break; + } + } + + cmd->framemode |= cmd->tx_data ? dmode : 0; + cmd->framemode |= cmd->addr_width ? CCR_ADMODE_1 : 0; +} + +static void stm32_qspi_read_fifo(u8 *val, void __iomem *addr) +{ + *val = readb_relaxed(addr); +} + +static void stm32_qspi_write_fifo(u8 *val, void __iomem *addr) +{ + writeb_relaxed(*val, addr); +} + +static int stm32_qspi_tx_poll(struct stm32_qspi *qspi, + const struct stm32_qspi_cmd *cmd) +{ + void (*tx_fifo)(u8 *, void __iomem *); + u32 len = cmd->len, sr; + u8 *buf = cmd->buf; + int ret; + + if (cmd->qspimode == CCR_FMODE_INDW) + tx_fifo = stm32_qspi_write_fifo; + else + tx_fifo = stm32_qspi_read_fifo; + + while (len--) { + ret = readl_relaxed_poll_timeout(qspi->io_base + QUADSPI_SR, + sr, (sr & SR_FTF), 10, + STM32_QSPI_FIFO_TIMEOUT_US); + if (ret) { + dev_err(qspi->dev, "fifo timeout (stat:%#x)\n", sr); + break; + } + tx_fifo(buf++, qspi->io_base + QUADSPI_DR); + } + + return ret; +} + +static int stm32_qspi_tx_mm(struct stm32_qspi *qspi, + const struct stm32_qspi_cmd *cmd) +{ + memcpy_fromio(cmd->buf, qspi->mm_base + cmd->addr, cmd->len); + return 0; +} + +static int stm32_qspi_tx(struct stm32_qspi *qspi, + const struct stm32_qspi_cmd *cmd) +{ + if (!cmd->tx_data) + return 0; + + if (cmd->qspimode == CCR_FMODE_MM) + return stm32_qspi_tx_mm(qspi, cmd); + + return stm32_qspi_tx_poll(qspi, cmd); +} + +static int stm32_qspi_send(struct stm32_qspi_flash *flash, + const struct stm32_qspi_cmd *cmd) +{ + struct stm32_qspi *qspi = flash->qspi; + u32 ccr, dcr, cr; + int err; + + err = stm32_qspi_wait_nobusy(qspi); + if (err) + goto abort; + + dcr = readl_relaxed(qspi->io_base + QUADSPI_DCR) & ~DCR_FSIZE_MASK; + dcr |= DCR_FSIZE(flash->fsize); + writel_relaxed(dcr, qspi->io_base + QUADSPI_DCR); + + cr = readl_relaxed(qspi->io_base + QUADSPI_CR); + cr &= ~CR_PRESC_MASK & ~CR_FSEL; + cr |= CR_PRESC(flash->presc); + cr |= flash->cs ? CR_FSEL : 0; + writel_relaxed(cr, qspi->io_base + QUADSPI_CR); + + if (cmd->tx_data) + writel_relaxed(cmd->len - 1, qspi->io_base + QUADSPI_DLR); + + ccr = cmd->framemode | cmd->qspimode; + + if (cmd->dummy) + ccr |= CCR_DCYC(cmd->dummy); + + if (cmd->addr_width) + ccr |= CCR_ADSIZE(cmd->addr_width - 1); + + ccr |= CCR_INST(cmd->opcode); + writel_relaxed(ccr, qspi->io_base + QUADSPI_CCR); + + if (cmd->addr_width && cmd->qspimode != CCR_FMODE_MM) + writel_relaxed(cmd->addr, qspi->io_base + QUADSPI_AR); + + err = stm32_qspi_tx(qspi, cmd); + if (err) + goto abort; + + if (cmd->qspimode != CCR_FMODE_MM) { + err = stm32_qspi_wait_cmd(qspi); + if (err) + goto abort; + writel_relaxed(FCR_CTCF, qspi->io_base + QUADSPI_FCR); + } + + return err; + +abort: + cr = readl_relaxed(qspi->io_base + QUADSPI_CR) | CR_ABORT; + writel_relaxed(cr, qspi->io_base + QUADSPI_CR); + + dev_err(qspi->dev, "%s abort err:%d\n", __func__, err); + return err; +} + +static int stm32_qspi_read_reg(struct spi_nor *nor, + u8 opcode, u8 *buf, int len) +{ + struct stm32_qspi_flash *flash = nor->priv; + struct device *dev = flash->qspi->dev; + struct stm32_qspi_cmd cmd; + + dev_dbg(dev, "read_reg: cmd:%#.2x buf:%p len:%#x\n", opcode, buf, len); + + memset(&cmd, 0, sizeof(cmd)); + cmd.opcode = opcode; + cmd.tx_data = true; + cmd.len = len; + cmd.buf = buf; + cmd.qspimode = CCR_FMODE_INDR; + + stm32_qspi_set_framemode(nor, &cmd, false); + + return stm32_qspi_send(flash, &cmd); +} + +static int stm32_qspi_write_reg(struct spi_nor *nor, u8 opcode, + u8 *buf, int len) +{ + struct stm32_qspi_flash *flash = nor->priv; + struct device *dev = flash->qspi->dev; + struct stm32_qspi_cmd cmd; + + dev_dbg(dev, "write_reg: cmd:%#.2x buf:%p len:%#x\n", opcode, buf, len); + + memset(&cmd, 0, sizeof(cmd)); + cmd.opcode = opcode; + cmd.tx_data = !!(buf && len > 0); + cmd.len = len; + cmd.buf = buf; + cmd.qspimode = CCR_FMODE_INDW; + + stm32_qspi_set_framemode(nor, &cmd, false); + + return stm32_qspi_send(flash, &cmd); +} + +static ssize_t stm32_qspi_read(struct spi_nor *nor, loff_t from, size_t len, + u_char *buf) +{ + struct stm32_qspi_flash *flash = nor->priv; + struct stm32_qspi *qspi = flash->qspi; + struct stm32_qspi_cmd cmd; + int err; + + dev_dbg(qspi->dev, "read(%#.2x): buf:%p from:%#.8x len:%#x\n", + nor->read_opcode, buf, (u32)from, len); + + memset(&cmd, 0, sizeof(cmd)); + cmd.opcode = nor->read_opcode; + cmd.addr_width = nor->addr_width; + cmd.addr = (u32)from; + cmd.tx_data = true; + cmd.dummy = nor->read_dummy; + cmd.len = len; + cmd.buf = buf; + cmd.qspimode = flash->read_mode; + + stm32_qspi_set_framemode(nor, &cmd, true); + err = stm32_qspi_send(flash, &cmd); + + return err ? err : len; +} + +static ssize_t stm32_qspi_write(struct spi_nor *nor, loff_t to, size_t len, + const u_char *buf) +{ + struct stm32_qspi_flash *flash = nor->priv; + struct device *dev = flash->qspi->dev; + struct stm32_qspi_cmd cmd; + int err; + + dev_dbg(dev, "write(%#.2x): buf:%p to:%#.8x len:%#x\n", + nor->program_opcode, buf, (u32)to, len); + + memset(&cmd, 0, sizeof(cmd)); + cmd.opcode = nor->program_opcode; + cmd.addr_width = nor->addr_width; + cmd.addr = (u32)to; + cmd.tx_data = true; + cmd.len = len; + cmd.buf = (void *)buf; + cmd.qspimode = CCR_FMODE_INDW; + + stm32_qspi_set_framemode(nor, &cmd, false); + err = stm32_qspi_send(flash, &cmd); + + return err ? err : len; +} + +static int stm32_qspi_erase(struct spi_nor *nor, loff_t offs) +{ + struct stm32_qspi_flash *flash = nor->priv; + struct device *dev = flash->qspi->dev; + struct stm32_qspi_cmd cmd; + + dev_dbg(dev, "erase(%#.2x):offs:%#x\n", nor->erase_opcode, (u32)offs); + + memset(&cmd, 0, sizeof(cmd)); + cmd.opcode = nor->erase_opcode; + cmd.addr_width = nor->addr_width; + cmd.addr = (u32)offs; + cmd.qspimode = CCR_FMODE_INDW; + + stm32_qspi_set_framemode(nor, &cmd, false); + + return stm32_qspi_send(flash, &cmd); +} + +static irqreturn_t stm32_qspi_irq(int irq, void *dev_id) +{ + struct stm32_qspi *qspi = (struct stm32_qspi *)dev_id; + u32 cr, sr, fcr = 0; + + cr = readl_relaxed(qspi->io_base + QUADSPI_CR); + sr = readl_relaxed(qspi->io_base + QUADSPI_SR); + + if ((cr & CR_TCIE) && (sr & SR_TCF)) { + /* tx complete */ + fcr |= FCR_CTCF; + complete(&qspi->cmd_completion); + } else { + dev_info_ratelimited(qspi->dev, "spurious interrupt\n"); + } + + writel_relaxed(fcr, qspi->io_base + QUADSPI_FCR); + + return IRQ_HANDLED; +} + +static int stm32_qspi_prep(struct spi_nor *nor, enum spi_nor_ops ops) +{ + struct stm32_qspi_flash *flash = nor->priv; + struct stm32_qspi *qspi = flash->qspi; + + mutex_lock(&qspi->lock); + return 0; +} + +static void stm32_qspi_unprep(struct spi_nor *nor, enum spi_nor_ops ops) +{ + struct stm32_qspi_flash *flash = nor->priv; + struct stm32_qspi *qspi = flash->qspi; + + mutex_unlock(&qspi->lock); +} + +static int stm32_qspi_flash_setup(struct stm32_qspi *qspi, + struct device_node *np) +{ + u32 width, flash_read, presc, cs_num, max_rate = 0; + struct stm32_qspi_flash *flash; + struct mtd_info *mtd; + int ret; + + of_property_read_u32(np, "reg", &cs_num); + if (cs_num >= STM32_MAX_NORCHIP) + return -EINVAL; + + of_property_read_u32(np, "spi-max-frequency", &max_rate); + if (!max_rate) + return -EINVAL; + + presc = DIV_ROUND_UP(qspi->clk_rate, max_rate) - 1; + + if (of_property_read_u32(np, "spi-rx-bus-width", &width)) + width = 1; + + if (width == 4) + flash_read = SPI_NOR_QUAD; + else if (width == 2) + flash_read = SPI_NOR_DUAL; + else if (width == 1) + flash_read = SPI_NOR_NORMAL; + else + return -EINVAL; + + flash = &qspi->flash[cs_num]; + flash->qspi = qspi; + flash->cs = cs_num; + flash->presc = presc; + + flash->nor.dev = qspi->dev; + spi_nor_set_flash_node(&flash->nor, np); + flash->nor.priv = flash; + mtd = &flash->nor.mtd; + + flash->nor.read = stm32_qspi_read; + flash->nor.write = stm32_qspi_write; + flash->nor.erase = stm32_qspi_erase; + flash->nor.read_reg = stm32_qspi_read_reg; + flash->nor.write_reg = stm32_qspi_write_reg; + flash->nor.prepare = stm32_qspi_prep; + flash->nor.unprepare = stm32_qspi_unprep; + + writel_relaxed(LPTR_DFT_TIMEOUT, qspi->io_base + QUADSPI_LPTR); + + writel_relaxed(CR_PRESC(presc) | CR_FTHRES(3) | CR_TCEN | CR_SSHIFT + | CR_EN, qspi->io_base + QUADSPI_CR); + + /* + * in stm32 qspi controller, QUADSPI_DCR register has a fsize field + * which define the size of nor flash. + * if fsize is NULL, the controller can't sent spi-nor command. + * set a temporary value just to discover the nor flash with + * "spi_nor_scan". After, the right value (mtd->size) can be set. + */ + flash->fsize = FSIZE_VAL(SZ_1K); + + ret = spi_nor_scan(&flash->nor, NULL, flash_read); + if (ret) { + dev_err(qspi->dev, "device scan failed\n"); + return ret; + } + + flash->fsize = FSIZE_VAL(mtd->size); + + flash->read_mode = CCR_FMODE_MM; + if (mtd->size > qspi->mm_size) + flash->read_mode = CCR_FMODE_INDR; + + writel_relaxed(DCR_CSHT(1), qspi->io_base + QUADSPI_DCR); + + ret = mtd_device_register(mtd, NULL, 0); + if (ret) { + dev_err(qspi->dev, "mtd device parse failed\n"); + return ret; + } + + flash->registered = true; + + dev_dbg(qspi->dev, "read mm:%s cs:%d bus:%d\n", + flash->read_mode == CCR_FMODE_MM ? "yes" : "no", cs_num, width); + + return 0; +} + +static void stm32_qspi_mtd_free(struct stm32_qspi *qspi) +{ + int i; + + for (i = 0; i < STM32_MAX_NORCHIP; i++) + if (qspi->flash[i].registered) + mtd_device_unregister(&qspi->flash[i].nor.mtd); +} + +static int stm32_qspi_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *flash_np; + struct reset_control *rstc; + struct stm32_qspi *qspi; + struct resource *res; + int ret, irq; + + qspi = devm_kzalloc(dev, sizeof(*qspi), GFP_KERNEL); + if (!qspi) + return -ENOMEM; + + qspi->nor_num = of_get_child_count(dev->of_node); + if (!qspi->nor_num || qspi->nor_num > STM32_MAX_NORCHIP) + return -ENODEV; + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi"); + qspi->io_base = devm_ioremap_resource(dev, res); + if (IS_ERR(qspi->io_base)) + return PTR_ERR(qspi->io_base); + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_mm"); + qspi->mm_base = devm_ioremap_resource(dev, res); + if (IS_ERR(qspi->mm_base)) + return PTR_ERR(qspi->mm_base); + + qspi->mm_size = resource_size(res); + + irq = platform_get_irq(pdev, 0); + ret = devm_request_irq(dev, irq, stm32_qspi_irq, 0, + dev_name(dev), qspi); + if (ret) { + dev_err(dev, "failed to request irq\n"); + return ret; + } + + init_completion(&qspi->cmd_completion); + + qspi->clk = devm_clk_get(dev, NULL); + if (IS_ERR(qspi->clk)) + return PTR_ERR(qspi->clk); + + qspi->clk_rate = clk_get_rate(qspi->clk); + if (!qspi->clk_rate) + return -EINVAL; + + ret = clk_prepare_enable(qspi->clk); + if (ret) { + dev_err(dev, "can not enable the clock\n"); + return ret; + } + + rstc = devm_reset_control_get(dev, NULL); + if (!IS_ERR(rstc)) { + reset_control_assert(rstc); + udelay(2); + reset_control_deassert(rstc); + } + + qspi->dev = dev; + platform_set_drvdata(pdev, qspi); + mutex_init(&qspi->lock); + + for_each_available_child_of_node(dev->of_node, flash_np) { + ret = stm32_qspi_flash_setup(qspi, flash_np); + if (ret) { + dev_err(dev, "unable to setup flash chip\n"); + goto err_flash; + } + } + + return 0; + +err_flash: + mutex_destroy(&qspi->lock); + stm32_qspi_mtd_free(qspi); + + clk_disable_unprepare(qspi->clk); + return ret; +} + +static int stm32_qspi_remove(struct platform_device *pdev) +{ + struct stm32_qspi *qspi = platform_get_drvdata(pdev); + + /* disable qspi */ + writel_relaxed(0, qspi->io_base + QUADSPI_CR); + + stm32_qspi_mtd_free(qspi); + mutex_destroy(&qspi->lock); + + clk_disable_unprepare(qspi->clk); + return 0; +} + +static const struct of_device_id stm32_qspi_match[] = { + {.compatible = "st,stm32f469-qspi"}, + {} +}; +MODULE_DEVICE_TABLE(of, stm32_qspi_match); + +static struct platform_driver stm32_qspi_driver = { + .probe = stm32_qspi_probe, + .remove = stm32_qspi_remove, + .driver = { + .name = "stm32-quadspi", + .of_match_table = stm32_qspi_match, + }, +}; +module_platform_driver(stm32_qspi_driver); + +MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>"); +MODULE_DESCRIPTION("STMicroelectronics STM32 quad spi driver"); +MODULE_LICENSE("GPL v2"); |