/* * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2021 SiFive * Copyright (c) 2021 Western Digital Corporation or its affiliates. * * Authors: * Green Wan * Anup Patel */ #include #include #include #include #include #include #include #include struct gpio_reset { struct gpio_pin pin; u32 active_delay; u32 inactive_delay; }; static struct gpio_reset poweroff = { .active_delay = 100, .inactive_delay = 100 }; static struct gpio_reset restart = { .active_delay = 100, .inactive_delay = 100 }; /* Custom mdelay function until we have a generic mdelay() API */ static void gpio_mdelay(unsigned long msecs) { volatile int i; while (msecs--) for (i = 0; i < 100000; i++) ; } static int gpio_system_reset_check(u32 type, u32 reason) { switch (type) { case SBI_SRST_RESET_TYPE_SHUTDOWN: case SBI_SRST_RESET_TYPE_COLD_REBOOT: case SBI_SRST_RESET_TYPE_WARM_REBOOT: return 1; } return 0; } static void gpio_system_reset(u32 type, u32 reason) { struct gpio_reset *reset = NULL; switch (type) { case SBI_SRST_RESET_TYPE_SHUTDOWN: reset = &poweroff; break; case SBI_SRST_RESET_TYPE_COLD_REBOOT: case SBI_SRST_RESET_TYPE_WARM_REBOOT: reset = &restart; break; } if (reset) { if (!reset->pin.chip) { sbi_printf("%s: gpio pin not available\n", __func__); goto skip_reset; } /* drive it active, also inactive->active edge */ gpio_direction_output(&reset->pin, 1); gpio_mdelay(reset->active_delay); /* drive inactive, also active->inactive edge */ gpio_set(&reset->pin, 0); gpio_mdelay(reset->inactive_delay); /* drive it active, also inactive->active edge */ gpio_set(&reset->pin, 1); skip_reset: /* hang !!! */ sbi_hart_hang(); } } static struct sbi_system_reset_device gpio_reset = { .name = "gpio-reset", .system_reset_check = gpio_system_reset_check, .system_reset = gpio_system_reset }; static int gpio_reset_init(void *fdt, int nodeoff, const struct fdt_match *match) { int rc, len; const fdt32_t *val; bool is_restart = (ulong)match->data; const char *dir_prop = (is_restart) ? "open-source" : "input"; struct gpio_reset *reset = (is_restart) ? &restart : &poweroff; rc = fdt_gpio_pin_get(fdt, nodeoff, 0, &reset->pin); if (rc) return rc; if (fdt_getprop(fdt, nodeoff, dir_prop, &len)) { rc = gpio_direction_input(&reset->pin); if (rc) return rc; } val = fdt_getprop(fdt, nodeoff, "active-delay-ms", &len); if (len > 0) reset->active_delay = fdt32_to_cpu(*val); val = fdt_getprop(fdt, nodeoff, "inactive-delay-ms", &len); if (len > 0) reset->inactive_delay = fdt32_to_cpu(*val); sbi_system_reset_set_device(&gpio_reset); return 0; } static const struct fdt_match gpio_poweroff_match[] = { { .compatible = "gpio-poweroff", .data = (void *)FALSE }, { }, }; struct fdt_reset fdt_poweroff_gpio = { .match_table = gpio_poweroff_match, .init = gpio_reset_init, }; static const struct fdt_match gpio_reset_match[] = { { .compatible = "gpio-restart", .data = (void *)TRUE }, { }, }; struct fdt_reset fdt_reset_gpio = { .match_table = gpio_reset_match, .init = gpio_reset_init, };