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>

1 files changed, 48 insertions, 0 deletions

diff --git a/src/drivers/uart/acpi/chip.h b/src/drivers/uart/acpi/chip.h
new file mode 100644
index 0000000000..03111650eb
--- /dev/null
+++ b/src/drivers/uart/acpi/chip.h
@@ -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__ */