platform/x86/amd: pmc: Clear metrics table at start of cycle

[ Upstream commit 4dbd1179 ]

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 9f5595d5
("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: 9f5595d5 ("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>