drivers/uart/acpi: Add new device driver for UART attached devices
This driver generates an ACPI device object for a UART attached device
with all of the expected device support handlers like different interrupt
sources and power control GPIOs.
Example use:
chip drivers/uart/acpi
register "name" = ""UDEV""
register "desc" = ""UART Attached Device""
register "hid" = "ACPI_DT_NAMESPACE_HID"
register "compat_string" = ""google,cros-ec-uart""
register "irq_gpio" = "ACPI_GPIO_IRQ_LEVEL_LOW_WAKE(GPP_C20)"
register "uart" = "ACPI_UART_RAW_DEVICE(115200, 64)"
device generic 0 on end
end
Resulting in this ACPI device:
Device (UDEV)
{
Name (_HID, "PRP0001")
Name (_UID, Zero)
Name (_DDN, "UART Attached Device")
Method (_STA, 0, NotSerialized)
{
Return (0x0F)
}
Name (_CRS, ResourceTemplate ()
{
UartSerialBusV2 (0x0001C200, DataBitsEight, StopBitsOne,
0x00, LittleEndian, ParityTypeNone, FlowControlNone,
0x0040, 0x0040, "\\_SB.PCI0.UAR2",
0x00, ResourceConsumer, , Exclusive)
GpioInt (Level, ActiveLow, ExclusiveAndWake, PullDefault, 0x0000,
"\\_SB.PCI0.GPIO", 0x00, ResourceConsumer)
{
0x0114
}
})
Name (_DSD, Package (0x02)
{
ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
Package (0x01)
{
Package (0x02)
{
"compatible",
"google,cros-ec-uart"
}
}
})
}
Change-Id: Idfd2d9d2ab6990a82ddd401734c0d9b1b0b8f82d
Signed-off-by: Duncan Laurie <dlaurie@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/41793
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
This commit is contained in:
Duncan Laurie
Furquan Shaikh
parent
dccef0da0c
commit
e530d816cc
|
|
@ -0,0 +1,2 @@
|
|||
config DRIVERS_UART_ACPI
|
||||
bool
|
||||
|
|
@ -0,0 +1 @@
|
|||
ramstage-$(CONFIG_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
|
||||
};
|
||||
|
|
@ -0,0 +1,48 @@
|
|||
/* SPDX-License-Identifier: GPL-2.0-or-later */
|
||||
|
||||
#ifndef __DRIVERS_UART_ACPI_H__
|
||||
#define __DRIVERS_UART_ACPI_H__
|
||||
|
||||
#include <acpi/acpi_device.h>
|
||||
|
||||
struct drivers_uart_acpi_config {
|
||||
const char *hid; /* ACPI _HID (required) */
|
||||
const char *cid; /* ACPI _CID */
|
||||
const char *name; /* ACPI Device Name */
|
||||
const char *desc; /* Device Description */
|
||||
unsigned int uid; /* ACPI _UID */
|
||||
unsigned int wake; /* Wake GPE */
|
||||
const char *compat_string; /* Compatible string for _HID=PRP0001 */
|
||||
struct acpi_irq irq; /* PIRQ */
|
||||
struct acpi_gpio irq_gpio; /* GPIO to be used instead of PIRQ */
|
||||
struct acpi_uart uart; /* UART device information */
|
||||
|
||||
/* Disable reset and enable GPIO export in _CRS */
|
||||
bool disable_gpio_export_in_crs;
|
||||
|
||||
/* Does the device have a power resource? */
|
||||
bool has_power_resource;
|
||||
|
||||
/* GPIO used to take device out of reset or to put it into reset. */
|
||||
struct acpi_gpio reset_gpio;
|
||||
/* Delay to be inserted after device is taken out of reset. */
|
||||
unsigned int reset_delay_ms;
|
||||
/* Delay to be inserted after device is put into reset. */
|
||||
unsigned int reset_off_delay_ms;
|
||||
|
||||
/* GPIO used to enable device. */
|
||||
struct acpi_gpio enable_gpio;
|
||||
/* Delay to be inserted after device is enabled. */
|
||||
unsigned int enable_delay_ms;
|
||||
/* Delay to be inserted after device is disabled. */
|
||||
unsigned int enable_off_delay_ms;
|
||||
|
||||
/* GPIO used to stop operation of device. */
|
||||
struct acpi_gpio stop_gpio;
|
||||
/* Delay to be inserted after disabling stop. */
|
||||
unsigned int stop_delay_ms;
|
||||
/* Delay to be inserted after enabling stop. */
|
||||
unsigned int stop_off_delay_ms;
|
||||
};
|
||||
|
||||
#endif /* __DRIVERS_UART_ACPI_H__ */
|
||||
Loading…
Reference in New Issue