https://github.com/torvalds/linux
Tip revision: 197b6b60ae7bc51dd0814953c562833143b292aa authored by Linus Torvalds on 26 March 2023, 21:40:20 UTC
Linux 6.3-rc4
Linux 6.3-rc4
Tip revision: 197b6b6
spi-gxp.c
// 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 write_len;
}
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");