diff options
Diffstat (limited to 'drivers/spi/spi-gxp.c')
-rw-r--r-- | drivers/spi/spi-gxp.c | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/drivers/spi/spi-gxp.c b/drivers/spi/spi-gxp.c new file mode 100644 index 000000000..21b07e251 --- /dev/null +++ b/drivers/spi/spi-gxp.c @@ -0,0 +1,321 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Copyright (C) 2022 Hewlett-Packard Development Company, L.P. */ + +#include <linux/iopoll.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi-mem.h> + +#define GXP_SPI0_MAX_CHIPSELECT 2 +#define GXP_SPI_SLEEP_TIME 1 +#define GXP_SPI_TIMEOUT (130 * 1000000 / GXP_SPI_SLEEP_TIME) + +#define MANUAL_MODE 0 +#define DIRECT_MODE 1 +#define SPILDAT_LEN 256 + +#define OFFSET_SPIMCFG 0x0 +#define OFFSET_SPIMCTRL 0x4 +#define OFFSET_SPICMD 0x5 +#define OFFSET_SPIDCNT 0x6 +#define OFFSET_SPIADDR 0x8 +#define OFFSET_SPIINTSTS 0xc + +#define SPIMCTRL_START 0x01 +#define SPIMCTRL_BUSY 0x02 +#define SPIMCTRL_DIR 0x08 + +struct gxp_spi; + +struct gxp_spi_chip { + struct gxp_spi *spifi; + u32 cs; +}; + +struct gxp_spi_data { + u32 max_cs; + u32 mode_bits; +}; + +struct gxp_spi { + const struct gxp_spi_data *data; + void __iomem *reg_base; + void __iomem *dat_base; + void __iomem *dir_base; + struct device *dev; + struct gxp_spi_chip chips[GXP_SPI0_MAX_CHIPSELECT]; +}; + +static void gxp_spi_set_mode(struct gxp_spi *spifi, int mode) +{ + u8 value; + void __iomem *reg_base = spifi->reg_base; + + value = readb(reg_base + OFFSET_SPIMCTRL); + + if (mode == MANUAL_MODE) { + writeb(0x55, reg_base + OFFSET_SPICMD); + writeb(0xaa, reg_base + OFFSET_SPICMD); + value &= ~0x30; + } else { + value |= 0x30; + } + writeb(value, reg_base + OFFSET_SPIMCTRL); +} + +static int gxp_spi_read_reg(struct gxp_spi_chip *chip, const struct spi_mem_op *op) +{ + int ret; + struct gxp_spi *spifi = chip->spifi; + void __iomem *reg_base = spifi->reg_base; + u32 value; + + value = readl(reg_base + OFFSET_SPIMCFG); + value &= ~(1 << 24); + value |= (chip->cs << 24); + value &= ~(0x07 << 16); + value &= ~(0x1f << 19); + writel(value, reg_base + OFFSET_SPIMCFG); + + writel(0, reg_base + OFFSET_SPIADDR); + + writeb(op->cmd.opcode, reg_base + OFFSET_SPICMD); + + writew(op->data.nbytes, reg_base + OFFSET_SPIDCNT); + + value = readb(reg_base + OFFSET_SPIMCTRL); + value &= ~SPIMCTRL_DIR; + value |= SPIMCTRL_START; + + writeb(value, reg_base + OFFSET_SPIMCTRL); + + ret = readb_poll_timeout(reg_base + OFFSET_SPIMCTRL, value, + !(value & SPIMCTRL_BUSY), + GXP_SPI_SLEEP_TIME, GXP_SPI_TIMEOUT); + if (ret) { + dev_warn(spifi->dev, "read reg busy time out\n"); + return ret; + } + + memcpy_fromio(op->data.buf.in, spifi->dat_base, op->data.nbytes); + return ret; +} + +static int gxp_spi_write_reg(struct gxp_spi_chip *chip, const struct spi_mem_op *op) +{ + int ret; + struct gxp_spi *spifi = chip->spifi; + void __iomem *reg_base = spifi->reg_base; + u32 value; + + value = readl(reg_base + OFFSET_SPIMCFG); + value &= ~(1 << 24); + value |= (chip->cs << 24); + value &= ~(0x07 << 16); + value &= ~(0x1f << 19); + writel(value, reg_base + OFFSET_SPIMCFG); + + writel(0, reg_base + OFFSET_SPIADDR); + + writeb(op->cmd.opcode, reg_base + OFFSET_SPICMD); + + memcpy_toio(spifi->dat_base, op->data.buf.in, op->data.nbytes); + + writew(op->data.nbytes, reg_base + OFFSET_SPIDCNT); + + value = readb(reg_base + OFFSET_SPIMCTRL); + value |= SPIMCTRL_DIR; + value |= SPIMCTRL_START; + + writeb(value, reg_base + OFFSET_SPIMCTRL); + + ret = readb_poll_timeout(reg_base + OFFSET_SPIMCTRL, value, + !(value & SPIMCTRL_BUSY), + GXP_SPI_SLEEP_TIME, GXP_SPI_TIMEOUT); + if (ret) + dev_warn(spifi->dev, "write reg busy time out\n"); + + return ret; +} + +static ssize_t gxp_spi_read(struct gxp_spi_chip *chip, const struct spi_mem_op *op) +{ + struct gxp_spi *spifi = chip->spifi; + u32 offset = op->addr.val; + + if (chip->cs == 0) + offset += 0x4000000; + + memcpy_fromio(op->data.buf.in, spifi->dir_base + offset, op->data.nbytes); + + return 0; +} + +static ssize_t gxp_spi_write(struct gxp_spi_chip *chip, const struct spi_mem_op *op) +{ + struct gxp_spi *spifi = chip->spifi; + void __iomem *reg_base = spifi->reg_base; + u32 write_len; + u32 value; + int ret; + + write_len = op->data.nbytes; + if (write_len > SPILDAT_LEN) + write_len = SPILDAT_LEN; + + value = readl(reg_base + OFFSET_SPIMCFG); + value &= ~(1 << 24); + value |= (chip->cs << 24); + value &= ~(0x07 << 16); + value |= (op->addr.nbytes << 16); + value &= ~(0x1f << 19); + writel(value, reg_base + OFFSET_SPIMCFG); + + writel(op->addr.val, reg_base + OFFSET_SPIADDR); + + writeb(op->cmd.opcode, reg_base + OFFSET_SPICMD); + + writew(write_len, reg_base + OFFSET_SPIDCNT); + + memcpy_toio(spifi->dat_base, op->data.buf.in, write_len); + + value = readb(reg_base + OFFSET_SPIMCTRL); + value |= SPIMCTRL_DIR; + value |= SPIMCTRL_START; + + writeb(value, reg_base + OFFSET_SPIMCTRL); + + ret = readb_poll_timeout(reg_base + OFFSET_SPIMCTRL, value, + !(value & SPIMCTRL_BUSY), + GXP_SPI_SLEEP_TIME, GXP_SPI_TIMEOUT); + if (ret) { + dev_warn(spifi->dev, "write busy time out\n"); + return ret; + } + + return 0; +} + +static int do_gxp_exec_mem_op(struct spi_mem *mem, const struct spi_mem_op *op) +{ + struct gxp_spi *spifi = spi_controller_get_devdata(mem->spi->master); + struct gxp_spi_chip *chip = &spifi->chips[mem->spi->chip_select]; + int ret; + + if (op->data.dir == SPI_MEM_DATA_IN) { + if (!op->addr.nbytes) + ret = gxp_spi_read_reg(chip, op); + else + ret = gxp_spi_read(chip, op); + } else { + if (!op->addr.nbytes) + ret = gxp_spi_write_reg(chip, op); + else + ret = gxp_spi_write(chip, op); + } + + return ret; +} + +static int gxp_exec_mem_op(struct spi_mem *mem, const struct spi_mem_op *op) +{ + int ret; + + ret = do_gxp_exec_mem_op(mem, op); + if (ret) + dev_err(&mem->spi->dev, "operation failed: %d", ret); + + return ret; +} + +static const struct spi_controller_mem_ops gxp_spi_mem_ops = { + .exec_op = gxp_exec_mem_op, +}; + +static int gxp_spi_setup(struct spi_device *spi) +{ + struct gxp_spi *spifi = spi_controller_get_devdata(spi->master); + unsigned int cs = spi->chip_select; + struct gxp_spi_chip *chip = &spifi->chips[cs]; + + chip->spifi = spifi; + chip->cs = cs; + + gxp_spi_set_mode(spifi, MANUAL_MODE); + + return 0; +} + +static int gxp_spifi_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + const struct gxp_spi_data *data; + struct spi_controller *ctlr; + struct gxp_spi *spifi; + int ret; + + data = of_device_get_match_data(&pdev->dev); + + ctlr = devm_spi_alloc_master(dev, sizeof(*spifi)); + if (!ctlr) + return -ENOMEM; + + spifi = spi_controller_get_devdata(ctlr); + + platform_set_drvdata(pdev, spifi); + spifi->data = data; + spifi->dev = dev; + + spifi->reg_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(spifi->reg_base)) + return PTR_ERR(spifi->reg_base); + + spifi->dat_base = devm_platform_ioremap_resource(pdev, 1); + if (IS_ERR(spifi->dat_base)) + return PTR_ERR(spifi->dat_base); + + spifi->dir_base = devm_platform_ioremap_resource(pdev, 2); + if (IS_ERR(spifi->dir_base)) + return PTR_ERR(spifi->dir_base); + + ctlr->mode_bits = data->mode_bits; + ctlr->bus_num = pdev->id; + ctlr->mem_ops = &gxp_spi_mem_ops; + ctlr->setup = gxp_spi_setup; + ctlr->num_chipselect = data->max_cs; + ctlr->dev.of_node = dev->of_node; + + ret = devm_spi_register_controller(dev, ctlr); + if (ret) { + return dev_err_probe(&pdev->dev, ret, + "failed to register spi controller\n"); + } + + return 0; +} + +static const struct gxp_spi_data gxp_spifi_data = { + .max_cs = 2, + .mode_bits = 0, +}; + +static const struct of_device_id gxp_spifi_match[] = { + {.compatible = "hpe,gxp-spifi", .data = &gxp_spifi_data }, + { /* null */ } +}; +MODULE_DEVICE_TABLE(of, gxp_spifi_match); + +static struct platform_driver gxp_spifi_driver = { + .probe = gxp_spifi_probe, + .driver = { + .name = "gxp-spifi", + .of_match_table = gxp_spifi_match, + }, +}; +module_platform_driver(gxp_spifi_driver); + +MODULE_DESCRIPTION("HPE GXP SPI Flash Interface driver"); +MODULE_AUTHOR("Nick Hawkins <nick.hawkins@hpe.com>"); +MODULE_LICENSE("GPL"); |