6.15-stable review patch. If anyone has any objections, please let me know.
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From: Mario Limonciello mario.limonciello@amd.com
[ Upstream commit 4dbd11796f3a8eb95647507befc41995458a4023 ]
The area of memory that contains the metrics table may contain garbage when the cycle starts. This normally doesn't matter because the cycle itself will populate it with valid data, however commit 9f5595d5f03fd ("platform/x86/amd: pmc: Require at least 2.5 seconds between HW sleep cycles") started to use it during the check() phase. Depending upon what garbage is in the table it's possible that the system will wait 2.5 seconds for even the first cycle, which will be visible to a user.
To prevent this from happening explicitly clear the table when logging is started.
Fixes: 9f5595d5f03fd ("platform/x86/amd: pmc: Require at least 2.5 seconds between HW sleep cycles") Signed-off-by: Mario Limonciello mario.limonciello@amd.com Link: https://lore.kernel.org/r/20250603132412.3555302-1-superm1@kernel.org Reviewed-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/platform/x86/amd/pmc/pmc.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/platform/x86/amd/pmc/pmc.c b/drivers/platform/x86/amd/pmc/pmc.c index 0329fafe14ebc..f45525bbd1549 100644 --- a/drivers/platform/x86/amd/pmc/pmc.c +++ b/drivers/platform/x86/amd/pmc/pmc.c @@ -157,6 +157,8 @@ static int amd_pmc_setup_smu_logging(struct amd_pmc_dev *dev) return -ENOMEM; }
+ memset_io(dev->smu_virt_addr, 0, sizeof(struct smu_metrics)); + /* Start the logging */ amd_pmc_send_cmd(dev, 0, NULL, SMU_MSG_LOG_RESET, false); amd_pmc_send_cmd(dev, 0, NULL, SMU_MSG_LOG_START, false);