[PATCH 10/23][SRU][OEM-5.6] platform/x86: intel_pmc_core: Dump low power status registers on an S0ix.y failure

AceLan Kao acelan.kao at canonical.com
Fri Oct 30 06:02:01 UTC 2020

From: Gayatri Kammela <gayatri.kammela at intel.com>

BugLink: https://bugs.launchpad.net/bugs/1899883

Platforms prior to Tiger Lake has no sub-states of S0ix and accessing
device PM states that are latched whenever there is a PC10 entry is
possible with the help of slp_s0_debug_status and slp_s0_dbg_latch
debugfs entries.

If a platform has sub-states of S0ix, no such entries are created.
Hence, dump low power status registers on resume When any attempt to
enter any low power state was unsuccessful.

Cc: Srinivas Pandruvada <srinivas.pandruvada at intel.com>
Cc: Andy Shevchenko <andriy.shevchenko at linux.intel.com>
Cc: David Box <david.e.box at intel.com>
Suggested-by: David Box <david.e.box at intel.com>
Signed-off-by: Gayatri Kammela <gayatri.kammela at intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com>
(cherry picked from commit 2e36ac08a98829b132a9d0bf1ca281af1a931747)
Signed-off-by: AceLan Kao <acelan.kao at canonical.com>
 drivers/platform/x86/intel_pmc_core.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/platform/x86/intel_pmc_core.c b/drivers/platform/x86/intel_pmc_core.c
index 19cd852293ff..20950b3d49fa 100644
--- a/drivers/platform/x86/intel_pmc_core.c
+++ b/drivers/platform/x86/intel_pmc_core.c
@@ -1285,6 +1285,8 @@ static inline bool pmc_core_is_s0ix_failed(struct pmc_dev *pmcdev)
 static int pmc_core_resume(struct device *dev)
 	struct pmc_dev *pmcdev = dev_get_drvdata(dev);
+	const struct pmc_bit_map **maps = pmcdev->map->lpm_sts;
+	int offset = pmcdev->map->lpm_status_offset;
 	if (!pmcdev->check_counters)
 		return 0;
@@ -1304,6 +1306,8 @@ static int pmc_core_resume(struct device *dev)
 	if (pmcdev->map->slps0_dbg_maps)
 		pmc_core_slps0_display(pmcdev, dev, NULL);
+	if (pmcdev->map->lpm_sts)
+		pmc_core_lpm_display(pmcdev, dev, NULL, offset, "STATUS", maps);
 	return 0;

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