diff options
| author | Kane Chen <kane.chen@intel.corp-partner.google.com> | 2022-11-03 23:18:44 +0800 |
|---|---|---|
| committer | Felix Held <felix-coreboot@felixheld.de> | 2022-11-07 14:36:10 +0000 |
| commit | 11be5562b2344e8395b64bba5f835d203ae4b910 (patch) | |
| tree | bfda01b62a2079abb2e687a9e5cf2e8dc4481e4f | |
| parent | 778c7af37ae399cfd72178f4585f3ba626ed84cf (diff) | |
soc/intel/common/block/pcie/rtd3: Skip Power On if _STA returns 1
RTD3,_ON method sometimes can create delays during system boot.
Even when the power is already up, kernel still tries to call _ON
method to power up device, but it's unnecessary.
RTD3._STA returns device power, so _ON method can check _STA and see
if the power on process can be skipped
BUG=b:249931687
TEST=system can boot to OS with RTD3 pcie storage and save ~80 ms on
Crota. Suspend stress test passes 100 cycles
Change-Id: I296ce1b85417a5dbaca558511cd7fc51a3a38c84
Signed-off-by: Kane Chen <kane.chen@intel.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/69189
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Reviewed-by: Subrata Banik <subratabanik@google.com>
| -rw-r--r-- | src/soc/intel/common/block/pcie/rtd3/rtd3.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/src/soc/intel/common/block/pcie/rtd3/rtd3.c b/src/soc/intel/common/block/pcie/rtd3/rtd3.c index f99ae44650..7a64734b6e 100644 --- a/src/soc/intel/common/block/pcie/rtd3/rtd3.c +++ b/src/soc/intel/common/block/pcie/rtd3/rtd3.c @@ -143,10 +143,30 @@ static void pcie_rtd3_acpi_method_srck(unsigned int pcie_rp, static void pcie_rtd3_acpi_method_on(unsigned int pcie_rp, const struct soc_intel_common_block_pcie_rtd3_config *config, - enum pcie_rp_type rp_type) + enum pcie_rp_type rp_type, + const struct device *dev) { + const struct device *parent = dev->bus->dev; + acpigen_write_method_serialized("_ON", 0); + /* The _STA returns current power status of device, so we can skip _ON + * if _STA returns 1 + * Example: + * Local0 = \_SB.PCI0.RP01.RTD3._STA () + * If ((Local0 == One)) + * { + * Return (One) + * } + */ + acpigen_write_store(); + acpigen_emit_namestring(acpi_device_path_join(parent, "RTD3._STA")); + acpigen_emit_byte(LOCAL0_OP); + acpigen_write_if_lequal_op_int(LOCAL0_OP, ONE_OP); + acpigen_write_return_op(ONE_OP); + acpigen_write_if_end(); + + /* When this feature is enabled, ONSK indicates if the previous _OFF was * skipped. If so, since the device was not in Off state, and the current * _ON can be skipped as well. @@ -448,7 +468,7 @@ static void pcie_rtd3_acpi_fill_ssdt(const struct device *dev) } pcie_rtd3_acpi_method_status(config); - pcie_rtd3_acpi_method_on(pcie_rp, config, rp_type); + pcie_rtd3_acpi_method_on(pcie_rp, config, rp_type, dev); pcie_rtd3_acpi_method_off(pcie_rp, config, rp_type); acpigen_pop_len(); /* PowerResource */ |