diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/brcm/iproc_gpio.c | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/drivers/brcm/iproc_gpio.c b/drivers/brcm/iproc_gpio.c new file mode 100644 index 0000000..f61a3bc --- /dev/null +++ b/drivers/brcm/iproc_gpio.c @@ -0,0 +1,232 @@ +/* + * Copyright (c) 2019-2020, Broadcom + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <assert.h> + +#include <drivers/gpio.h> +#include <lib/mmio.h> +#include <plat/common/platform.h> + +#include <iproc_gpio.h> +#include <platform_def.h> + +#define IPROC_GPIO_DATA_IN_OFFSET 0x00 +#define IPROC_GPIO_DATA_OUT_OFFSET 0x04 +#define IPROC_GPIO_OUT_EN_OFFSET 0x08 +#define IPROC_GPIO_PAD_RES_OFFSET 0x34 +#define IPROC_GPIO_RES_EN_OFFSET 0x38 + +#define PINMUX_OFFSET(gpio) ((gpio) * 4) +#define PINCONF_OFFSET(gpio) ((gpio) * 4) +#define PINCONF_PULL_UP BIT(4) +#define PINCONF_PULL_DOWN BIT(5) + +/* + * iProc GPIO bank is always 0x200 per bank, + * with each bank supporting 32 GPIOs. + */ +#define GPIO_BANK_SIZE 0x200 +#define NGPIOS_PER_BANK 32 +#define GPIO_BANK(pin) ((pin) / NGPIOS_PER_BANK) + +#define IPROC_GPIO_REG(pin, reg) (GPIO_BANK(pin) * GPIO_BANK_SIZE + (reg)) +#define IPROC_GPIO_SHIFT(pin) ((pin) % NGPIOS_PER_BANK) + +#define MUX_GPIO_MODE 0x3 + +/* + * @base: base address of the gpio controller + * @pinconf_base: base address of the pinconf + * @pinmux_base: base address of the mux controller + * @nr_gpios: maxinum number of GPIOs + */ +struct iproc_gpio { + uintptr_t base; + uintptr_t pinconf_base; + uintptr_t pinmux_base; + int nr_gpios; +}; + +static struct iproc_gpio iproc_gpio; + +static void gpio_set_bit(uintptr_t base, unsigned int reg, int gpio, bool set) +{ + unsigned int offset = IPROC_GPIO_REG(gpio, reg); + unsigned int shift = IPROC_GPIO_SHIFT(gpio); + uint32_t val; + + val = mmio_read_32(base + offset); + if (set) + val |= BIT(shift); + else + val &= ~BIT(shift); + + mmio_write_32(base + offset, val); +} + +static bool gpio_get_bit(uintptr_t base, unsigned int reg, int gpio) +{ + unsigned int offset = IPROC_GPIO_REG(gpio, reg); + unsigned int shift = IPROC_GPIO_SHIFT(gpio); + + return !!(mmio_read_32(base + offset) & BIT(shift)); +} + +static void mux_to_gpio(struct iproc_gpio *g, int gpio) +{ + /* mux pad to GPIO if IOPAD configuration is mandatory */ + if (g->pinmux_base) + mmio_write_32(g->pinmux_base + PINMUX_OFFSET(gpio), + MUX_GPIO_MODE); +} + +static void set_direction(int gpio, int direction) +{ + struct iproc_gpio *g = &iproc_gpio; + bool dir = (direction == GPIO_DIR_OUT) ? true : false; + + assert(gpio < g->nr_gpios); + + mux_to_gpio(g, gpio); + gpio_set_bit(g->base, IPROC_GPIO_OUT_EN_OFFSET, gpio, dir); +} + +static int get_direction(int gpio) +{ + struct iproc_gpio *g = &iproc_gpio; + int dir; + + assert(gpio < g->nr_gpios); + + mux_to_gpio(g, gpio); + dir = gpio_get_bit(g->base, IPROC_GPIO_OUT_EN_OFFSET, gpio) ? + GPIO_DIR_OUT : GPIO_DIR_IN; + + return dir; +} + +static int get_value(int gpio) +{ + struct iproc_gpio *g = &iproc_gpio; + unsigned int offset; + + assert(gpio < g->nr_gpios); + + mux_to_gpio(g, gpio); + + /* + * If GPIO is configured as output, read from the GPIO_OUT register; + * otherwise, read from the GPIO_IN register + */ + offset = gpio_get_bit(g->base, IPROC_GPIO_OUT_EN_OFFSET, gpio) ? + IPROC_GPIO_DATA_OUT_OFFSET : IPROC_GPIO_DATA_IN_OFFSET; + + return gpio_get_bit(g->base, offset, gpio); +} + +static void set_value(int gpio, int val) +{ + struct iproc_gpio *g = &iproc_gpio; + + assert(gpio < g->nr_gpios); + + mux_to_gpio(g, gpio); + + /* make sure GPIO is configured to output, and then set the value */ + gpio_set_bit(g->base, IPROC_GPIO_OUT_EN_OFFSET, gpio, true); + gpio_set_bit(g->base, IPROC_GPIO_DATA_OUT_OFFSET, gpio, !!(val)); +} + +static int get_pull(int gpio) +{ + struct iproc_gpio *g = &iproc_gpio; + uint32_t val; + + assert(gpio < g->nr_gpios); + mux_to_gpio(g, gpio); + + /* when there's a valid pinconf_base, use it */ + if (g->pinconf_base) { + val = mmio_read_32(g->pinconf_base + PINCONF_OFFSET(gpio)); + + if (val & PINCONF_PULL_UP) + return GPIO_PULL_UP; + else if (val & PINCONF_PULL_DOWN) + return GPIO_PULL_DOWN; + else + return GPIO_PULL_NONE; + } + + /* no pinconf_base. fall back to GPIO internal pull control */ + if (!gpio_get_bit(g->base, IPROC_GPIO_RES_EN_OFFSET, gpio)) + return GPIO_PULL_NONE; + + return gpio_get_bit(g->base, IPROC_GPIO_PAD_RES_OFFSET, gpio) ? + GPIO_PULL_UP : GPIO_PULL_DOWN; +} + +static void set_pull(int gpio, int pull) +{ + struct iproc_gpio *g = &iproc_gpio; + uint32_t val; + + assert(gpio < g->nr_gpios); + mux_to_gpio(g, gpio); + + /* when there's a valid pinconf_base, use it */ + if (g->pinconf_base) { + val = mmio_read_32(g->pinconf_base + PINCONF_OFFSET(gpio)); + + if (pull == GPIO_PULL_NONE) { + val &= ~(PINCONF_PULL_UP | PINCONF_PULL_DOWN); + } else if (pull == GPIO_PULL_UP) { + val |= PINCONF_PULL_UP; + val &= ~PINCONF_PULL_DOWN; + } else if (pull == GPIO_PULL_DOWN) { + val |= PINCONF_PULL_DOWN; + val &= ~PINCONF_PULL_UP; + } else { + return; + } + mmio_write_32(g->pinconf_base + PINCONF_OFFSET(gpio), val); + } + + /* no pinconf_base. fall back to GPIO internal pull control */ + if (pull == GPIO_PULL_NONE) { + gpio_set_bit(g->base, IPROC_GPIO_RES_EN_OFFSET, gpio, false); + return; + } + + /* enable pad register and pull up or down */ + gpio_set_bit(g->base, IPROC_GPIO_RES_EN_OFFSET, gpio, true); + gpio_set_bit(g->base, IPROC_GPIO_PAD_RES_OFFSET, gpio, + !!(pull == GPIO_PULL_UP)); +} + +const gpio_ops_t iproc_gpio_ops = { + .get_direction = get_direction, + .set_direction = set_direction, + .get_value = get_value, + .set_value = set_value, + .get_pull = get_pull, + .set_pull = set_pull, +}; + +void iproc_gpio_init(uintptr_t base, int nr_gpios, uintptr_t pinmux_base, + uintptr_t pinconf_base) +{ + iproc_gpio.base = base; + iproc_gpio.nr_gpios = nr_gpios; + + /* pinmux/pinconf base is optional for some SoCs */ + if (pinmux_base) + iproc_gpio.pinmux_base = pinmux_base; + + if (pinconf_base) + iproc_gpio.pinconf_base = pinconf_base; + + gpio_init(&iproc_gpio_ops); +} |