diff options
Diffstat (limited to 'lib/utils/gpio/fdt_gpio_sifive.c')
-rw-r--r-- | lib/utils/gpio/fdt_gpio_sifive.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/lib/utils/gpio/fdt_gpio_sifive.c b/lib/utils/gpio/fdt_gpio_sifive.c new file mode 100644 index 0000000..abc9d72 --- /dev/null +++ b/lib/utils/gpio/fdt_gpio_sifive.c @@ -0,0 +1,105 @@ +/* + * SPDX-License-Identifier: BSD-2-Clause + * + * Copyright (c) 2021 SiFive + * + * Authors: + * Green Wan <green.wan@sifive.com> + */ + +#include <sbi/riscv_io.h> +#include <sbi/sbi_error.h> +#include <sbi_utils/fdt/fdt_helper.h> +#include <sbi_utils/gpio/fdt_gpio.h> + +#define SIFIVE_GPIO_CHIP_MAX 2 + +#define SIFIVE_GPIO_PINS_MIN 1 +#define SIFIVE_GPIO_PINS_MAX 32 +#define SIFIVE_GPIO_PINS_DEF 16 + +#define SIFIVE_GPIO_OUTEN 0x8 +#define SIFIVE_GPIO_OUTVAL 0xc +#define SIFIVE_GPIO_BIT(b) (1U << (b)) + +struct sifive_gpio_chip { + unsigned long addr; + struct gpio_chip chip; +}; + +static unsigned int sifive_gpio_chip_count; +static struct sifive_gpio_chip sifive_gpio_chip_array[SIFIVE_GPIO_CHIP_MAX]; + +static int sifive_gpio_direction_output(struct gpio_pin *gp, int value) +{ + unsigned int v; + struct sifive_gpio_chip *chip = + container_of(gp->chip, struct sifive_gpio_chip, chip); + + v = readl((volatile void *)(chip->addr + SIFIVE_GPIO_OUTEN)); + v |= SIFIVE_GPIO_BIT(gp->offset); + writel(v, (volatile void *)(chip->addr + SIFIVE_GPIO_OUTEN)); + + v = readl((volatile void *)(chip->addr + SIFIVE_GPIO_OUTVAL)); + if (!value) + v &= ~SIFIVE_GPIO_BIT(gp->offset); + else + v |= SIFIVE_GPIO_BIT(gp->offset); + writel(v, (volatile void *)(chip->addr + SIFIVE_GPIO_OUTVAL)); + + return 0; +} + +static void sifive_gpio_set(struct gpio_pin *gp, int value) +{ + unsigned int v; + struct sifive_gpio_chip *chip = + container_of(gp->chip, struct sifive_gpio_chip, chip); + + v = readl((volatile void *)(chip->addr + SIFIVE_GPIO_OUTVAL)); + if (!value) + v &= ~SIFIVE_GPIO_BIT(gp->offset); + else + v |= SIFIVE_GPIO_BIT(gp->offset); + writel(v, (volatile void *)(chip->addr + SIFIVE_GPIO_OUTVAL)); +} + +extern struct fdt_gpio fdt_gpio_sifive; + +static int sifive_gpio_init(void *fdt, int nodeoff, u32 phandle, + const struct fdt_match *match) +{ + int rc; + struct sifive_gpio_chip *chip; + + if (SIFIVE_GPIO_CHIP_MAX <= sifive_gpio_chip_count) + return SBI_ENOSPC; + chip = &sifive_gpio_chip_array[sifive_gpio_chip_count]; + + rc = fdt_get_node_addr_size(fdt, nodeoff, &chip->addr, NULL); + if (rc) + return rc; + + chip->chip.driver = &fdt_gpio_sifive; + chip->chip.id = phandle; + chip->chip.ngpio = SIFIVE_GPIO_PINS_DEF; + chip->chip.direction_output = sifive_gpio_direction_output; + chip->chip.set = sifive_gpio_set; + rc = gpio_chip_add(&chip->chip); + if (rc) + return rc; + + sifive_gpio_chip_count++; + return 0; +} + +static const struct fdt_match sifive_gpio_match[] = { + { .compatible = "sifive,gpio0" }, + { }, +}; + +struct fdt_gpio fdt_gpio_sifive = { + .match_table = sifive_gpio_match, + .xlate = fdt_gpio_simple_xlate, + .init = sifive_gpio_init, +}; |