diff options
Diffstat (limited to 'src/drivers/uart/acpi/acpi.c')
| -rw-r--r-- | src/drivers/uart/acpi/acpi.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/src/drivers/uart/acpi/acpi.c b/src/drivers/uart/acpi/acpi.c new file mode 100644 index 0000000000..9b4d1fa7f0 --- /dev/null +++ b/src/drivers/uart/acpi/acpi.c @@ -0,0 +1,174 @@ +/* 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. Request to explicitly disable export of GPIOs in CRS, or + * 2. Both reset and enable GPIOs are not provided. + */ + if (config->disable_gpio_export_in_crs || + ((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 (!dev->enabled || !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_COLD); + 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.polarity); + if (reset_gpio_index >= 0) + acpi_dp_add_gpio(dsd, "reset-gpios", path, + reset_gpio_index, 0, + config->reset_gpio.polarity); + if (enable_gpio_index >= 0) + acpi_dp_add_gpio(dsd, "enable-gpios", path, + enable_gpio_index, 0, + config->enable_gpio.polarity); + 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 +}; |