acpi: Accomodate non-standard UUIDs in device properties

There have been changes to the way device properties are supported
in Linux[1] and Windows[2] which add flexibilty:

- non-standard UUIDs can be used instead of only ACPI_DP_UUID
- support for multiple different packages within the _DSD that
associate different properties with unique UUIDs.

To handle this I extracted the part that does the write of UUID and
properties to a separate function and defined a new PACKAGE type
which has the custom UUID as a name and can be used the same way that
child properties are today.

For example a PCIe root port for a USB4 port has a standard property
indicating the USB4 reference, and then two custom properties which
are defined for different attributes.

Example code:

/* Create property table */
acpi_dp *dsd = acpi_dp_new_table("_DSD");
acpi_dp_add_reference(dsd, "usb4-port", usb4_path);

/* Add package for hotplug */
acpi_dp *pkg = acpi_dp_new_table("6211e2c0-58a3-4af3-90e1-927a4e0c55a4");
acpi_dp_add_integer(pkg, "HotPlugSupportInD3", 1);
acpi_dp_add_package(dsd, pkg);

/* Add package for external port info */
pkg = acpi_dp_new_table("efcc06cc-73ac-4bc3-bff0-76143807c389");
acpi_dp_add_integer(pkg, "ExternalFacingPort", 1);
acpi_dp_add_package(dsd, pkg);

/* Write all properties */
acpi_dp_write(dsd);

Resulting ACPI:

Scope (\_SB.PCI0.TRP0)
{
    Name (_DSD, Package ()
    {
        ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301")
        Package ()
        {
            Package () { "usb4-port", \_SB.PCI0.TDM0.RHUB.PRTA }
        },

        ToUUID ("6211e2c0-58a3-4af3-90e1-927a4e0c55a4"),
        Package ()
        {
            Package () { "HotPlugSupportInD3", One }
        },

        ToUUID ("efcc06cc-73ac-4bc3-bff0-76143807c389"),
        Package ()
        {
            Package () { "ExternalFacingPort", One },
        }
    })
}

[1] https://patchwork.kernel.org/patch/10599675/
[2] https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports

Change-Id: I75f47825bf4ffc5e9e92af2c45790d1b5945576e
Signed-off-by: Duncan Laurie <dlaurie@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/42047
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>
This commit is contained in:
Duncan Laurie
2020-06-03 12:36:51 -07:00
committed by Furquan Shaikh
parent fba0ad84d1
commit 84fac41d35
2 changed files with 77 additions and 31 deletions

View File

@@ -15,11 +15,13 @@ enum acpi_dp_type {
ACPI_DP_TYPE_TABLE,
ACPI_DP_TYPE_ARRAY,
ACPI_DP_TYPE_CHILD,
ACPI_DP_TYPE_PACKAGE,
};
struct acpi_dp {
enum acpi_dp_type type;
const char *name;
const char *uuid;
struct acpi_dp *next;
union {
struct acpi_dp *child;
@@ -464,6 +466,9 @@ void acpi_device_add_power_res(const struct acpi_power_res_params *params);
/* Start a new Device Property table with provided ACPI reference */
struct acpi_dp *acpi_dp_new_table(const char *ref);
/* Add package of device properties with a unique UUID */
struct acpi_dp *acpi_dp_add_package(struct acpi_dp *dp, struct acpi_dp *package);
/* Add integer Device Property */
struct acpi_dp *acpi_dp_add_integer(struct acpi_dp *dp, const char *name,
uint64_t value);