/* SPDX-License-Identifier: GPL-2.0-or-later */ #include <acpi/acpi_device.h> #include <acpi/acpigen.h> #include <console/console.h> #include <device/path.h> #include <string.h> #include "chip.h" static bool uart_acpi_add_gpios_to_crs(struct drivers_uart_acpi_config *config) { /* * Return false if: * 1. GPIOs are exported via a power resource, or * 2. Both reset and enable GPIOs are not provided. */ if (config->has_power_resource || ((config->reset_gpio.pin_count == 0) && (config->enable_gpio.pin_count == 0))) return false; return true; } static int uart_acpi_write_gpio(struct acpi_gpio *gpio, int *curr_index) { int ret = -1; if (gpio->pin_count == 0) return ret; acpi_device_write_gpio(gpio); ret = *curr_index; (*curr_index)++; return ret; } static void uart_acpi_fill_ssdt(const struct device *dev) { const char *scope = acpi_device_scope(dev); const char *path = acpi_device_path(dev); struct drivers_uart_acpi_config *config = dev->chip_info; int curr_index = 0; int irq_gpio_index = -1; int reset_gpio_index = -1; int enable_gpio_index = -1; if (!scope) return; if (!config->hid) { printk(BIOS_ERR, "%s: ERROR: HID required\n", dev_path(dev)); return; } acpigen_write_scope(scope); acpigen_write_device(acpi_device_name(dev)); acpigen_write_name_string("_HID", config->hid); if (config->cid) acpigen_write_name_string("_CID", config->cid); acpigen_write_name_integer("_UID", config->uid); acpigen_write_name_string("_DDN", config->desc); acpigen_write_STA(acpi_device_status(dev)); /* Resources */ acpigen_write_name("_CRS"); acpigen_write_resourcetemplate_header(); /* Fix up resource pointer to this scope */ config->uart.resource = scope; acpi_device_write_uart(&config->uart); /* Use either Interrupt() or GpioInt() */ if (config->irq_gpio.pin_count) acpi_device_write_gpio(&config->irq_gpio); else acpi_device_write_interrupt(&config->irq); /* Add enable/reset GPIOs if needed */ if (uart_acpi_add_gpios_to_crs(config)) { reset_gpio_index = uart_acpi_write_gpio(&config->reset_gpio, &curr_index); enable_gpio_index = uart_acpi_write_gpio(&config->enable_gpio, &curr_index); } acpigen_write_resourcetemplate_footer(); /* Wake capabilities */ if (config->wake) { acpigen_write_name_integer("_S0W", ACPI_DEVICE_SLEEP_D3_HOT); acpigen_write_PRW(config->wake, SLP_TYP_S3); }; /* Write device properties if needed */ if (config->compat_string || irq_gpio_index >= 0 || reset_gpio_index >= 0 || enable_gpio_index >= 0) { struct acpi_dp *dsd = acpi_dp_new_table("_DSD"); if (config->compat_string) acpi_dp_add_string(dsd, "compatible", config->compat_string); if (irq_gpio_index >= 0) acpi_dp_add_gpio(dsd, "irq-gpios", path, irq_gpio_index, 0, config->irq_gpio.active_low); if (reset_gpio_index >= 0) acpi_dp_add_gpio(dsd, "reset-gpios", path, reset_gpio_index, 0, config->reset_gpio.active_low); if (enable_gpio_index >= 0) acpi_dp_add_gpio(dsd, "enable-gpios", path, enable_gpio_index, 0, config->enable_gpio.active_low); acpi_dp_write(dsd); } /* Power Resource */ if (config->has_power_resource) { const struct acpi_power_res_params power_res_params = { &config->reset_gpio, config->reset_delay_ms, config->reset_off_delay_ms, &config->enable_gpio, config->enable_delay_ms, config->enable_off_delay_ms, &config->stop_gpio, config->stop_delay_ms, config->stop_off_delay_ms }; acpi_device_add_power_res(&power_res_params); } acpigen_pop_len(); /* Device */ acpigen_pop_len(); /* Scope */ printk(BIOS_INFO, "%s: %s at %s\n", path, config->desc, dev_path(dev)); } static const char *uart_acpi_name(const struct device *dev) { struct drivers_uart_acpi_config *config = dev->chip_info; static char name[5]; if (config->name) return config->name; snprintf(name, sizeof(name), "D%03.3X", dev->path.generic.id); return name; } static struct device_operations uart_acpi_dev_ops = { .read_resources = noop_read_resources, .set_resources = noop_set_resources, .acpi_fill_ssdt = uart_acpi_fill_ssdt, .acpi_name = uart_acpi_name, }; static void uart_acpi_enable(struct device *dev) { struct drivers_uart_acpi_config *config = dev->chip_info; if (config->desc) dev->name = config->desc; else config->desc = dev->chip_ops->name; dev->ops = &uart_acpi_dev_ops; } struct chip_operations drivers_uart_acpi_ops = { CHIP_NAME("ACPI UART Device") .enable_dev = uart_acpi_enable };