From 7227cef0d7baafdabf9294ad577c09a5d4e93e43 Mon Sep 17 00:00:00 2001 From: John Zhao Date: Mon, 13 Sep 2021 12:31:39 -0700 Subject: [PATCH] soc/intel/tigerlake: Add ACPI addition for USB4/TBT latency optimization The PCI-SIG engineering change requirement provides the ACPI additions for firmware latency optimization. This change adds additional ACPI DSM function with both of FW_RESET_TIME and FW_D3HOT_TO_D0_TIME to the USB4/TBT topology. The OS is informed to reduce latency for upstream ports while connecting USB4/TBT devices. BUG=b:199757442 TEST=It was validated that the first connected device waits only 50ms instead of 100ms and all functions work on Voxel board. Signed-off-by: John Zhao Change-Id: I5a19118b75ed0a78b7436f2f90295c03928300d7 Reviewed-on: https://review.coreboot.org/c/coreboot/+/57625 Tested-by: build bot (Jenkins) Reviewed-by: Tim Wawrzynczak --- src/soc/intel/tigerlake/acpi/tcss_pcierp.asl | 59 ++++++++++++++++++++ 1 file changed, 59 insertions(+) diff --git a/src/soc/intel/tigerlake/acpi/tcss_pcierp.asl b/src/soc/intel/tigerlake/acpi/tcss_pcierp.asl index 847d87ea6e..7576564dfb 100644 --- a/src/soc/intel/tigerlake/acpi/tcss_pcierp.asl +++ b/src/soc/intel/tigerlake/acpi/tcss_pcierp.asl @@ -1,5 +1,25 @@ /* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * The PCI-SIG engineering change requirement provides the ACPI additions for firmware latency + * optimization. Both of FW_RESET_TIME and FW_D3HOT_TO_D0_TIME are applicable to the upstream + * port of the USB4/TBT topology. + */ +/* Number of microseconds to wait after a conventional reset */ +#define FW_RESET_TIME 50000 + +/* Number of microseconds to wait after data link layer active report */ +#define FW_DL_UP_TIME 1 + +/* Number of microseconds to wait after a function level reset */ +#define FW_FLR_RESET_TIME 1 + +/* Number of microseconds to wait from D3 hot to D0 transition */ +#define FW_D3HOT_TO_D0_TIME 50000 + +/* Number of microseconds to wait after setting the VF enable bit */ +#define FW_VF_ENABLE_TIME 1 + OperationRegion (PXCS, SystemMemory, BASE(_ADR), 0x800) Field (PXCS, AnyAcc, NoLock, Preserve) { @@ -64,10 +84,49 @@ Method (_DSM, 4, Serialized) Return (Buffer() { 0x00 }) } +/* + * A bitmask of functions support + */ +Name(OPTS, Buffer(2) {0, 0}) + Device (PXSX) { Name (_ADR, 0x00000000) + /* + * _DSM Device Specific Method + * + * Arg0: UUID: E5C937D0-3553-4d7a-9117-EA4D19C3434D + * Arg1: Revision ID: 3 + * Arg2: Function index: 0, 9 + * Arg3: Empty package + */ + Method (_DSM, 4, Serialized) + { + If (Arg0 == ToUUID("E5C937D0-3553-4d7a-9117-EA4D19C3434D")) { + If (Arg1 >= 3) { + If (Arg2 == 0) { + /* + * Function index: 0 + * Standard query - A bitmask of functions supported + */ + CreateBitField(OPTS, 9, FUN9) + FUN9 = 1 + Return (OPTS) + } ElseIf (Arg2 == 9) { + /* + * Function index: 9 + * Specifying device readiness durations + */ + Return (Package() { FW_RESET_TIME, FW_DL_UP_TIME, + FW_FLR_RESET_TIME, FW_D3HOT_TO_D0_TIME, + FW_VF_ENABLE_TIME }) + } + } + } + Return (Buffer() { 0x0 }) + } + Method (_PRW, 0) { Return (Package() { 0x69, 4 })