From db6d1983da9559b3910e6833be68029f73c0f258 Mon Sep 17 00:00:00 2001 From: Evan Green Date: Fri, 22 Apr 2022 10:55:15 -0700 Subject: soc/intel/common/block/acpi: Fill PEP S0 mask on failure There is a bug floating around where communciation with the PMC fails after transitions through S3/S4/S5. This CL does not address that issue. However in working with error cases presented by a failing PMC, we're forced into an early return in read_pmc_lpm_requirements(), which sets up _DSM buffers in the SSDT for the PEP device. The function itself returns void, so the error is swallowed regardless. However returning early is not the appropriate action because it causes the size of the buffer written into the _DSM method to change. This causes the SSDT to change size and layout across an S3 or S4 transition, which results in mayhem in the kernel, as the kernel is not expecting these tables to change out from under it. Instead of returning early, it's better to simply print the error and keep going, attaching a zeroed out buffer for the substate requirements. This results in an empty requirements mask for all states. From what I can see in the kernel this is no more broken than today's behavior, as this buffer seems to only be used for printing a debugfs file. In fact in this particular case the kernel doesn't even notice, as this buffer is copied out at boot, and not refreshed at resume. BUG=b:230031158 TEST=hibernate and resume on Primus4ES Signed-off-by: Evan Green Change-Id: Ibe35d50b350b1b96dea313dfcbd00745970c16ab Reviewed-on: https://review.coreboot.org/c/coreboot/+/63790 Tested-by: build bot (Jenkins) Reviewed-by: Tim Wawrzynczak Reviewed-by: Subrata Banik --- src/soc/intel/common/block/acpi/pep.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'src/soc') diff --git a/src/soc/intel/common/block/acpi/pep.c b/src/soc/intel/common/block/acpi/pep.c index c7f1270b36..b83b71491f 100644 --- a/src/soc/intel/common/block/acpi/pep.c +++ b/src/soc/intel/common/block/acpi/pep.c @@ -56,8 +56,6 @@ static void read_pmc_lpm_requirements(const struct soc_pmc_lpm *lpm, if (result != CB_SUCCESS) { printk(BIOS_ERR, "Failed to retrieve LPM substate registers" "from LPM, substate %zu, reg %zu\n", i, j); - free(reg); - return; } uint32_t *ptr = reg + i * lpm->num_req_regs + j; -- cgit v1.2.3