Hi,
On 8/30/2024 2:53 AM, Ilpo Järvinen wrote:
On Thu, 8 Aug 2024, Xi Pardee wrote:
From: Xi Pardee <xi.pardee@xxxxxxxxx>
Add support to ignore all LTRs before suspend and restore the previous
LTR values after suspend. This feature could be turned off with module
parameter ltr_ignore_all_suspend.
This does not answer why? question.
I will add the reason to commit message in next version.
Suggested-by: Rafael J. Wysocki<rafael.j.wysocki@xxxxxxxxx>
Please add a space between the name and email.
This patch seems to have fallen through cracks and did not appear in the
patchwork at all.
Will add a space between the name and email.
Signed-off-by: Xi Pardee <xi.pardee@xxxxxxxxx>
---
drivers/platform/x86/intel/pmc/core.c | 53 +++++++++++++++++++++++++++
drivers/platform/x86/intel/pmc/core.h | 2 +
2 files changed, 55 insertions(+)
diff --git a/drivers/platform/x86/intel/pmc/core.c b/drivers/platform/x86/intel/pmc/core.c
index 01ae71c6df59..f364a011721d 100644
--- a/drivers/platform/x86/intel/pmc/core.c
+++ b/drivers/platform/x86/intel/pmc/core.c
@@ -714,6 +714,49 @@ static int pmc_core_s0ix_blocker_show(struct seq_file *s, void *unused)
}
DEFINE_SHOW_ATTRIBUTE(pmc_core_s0ix_blocker);
+static void pmc_core_ltr_ignore_all(struct pmc_dev *pmcdev)
+{
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(pmcdev->pmcs); i++) {
+ struct pmc *pmc;
+ u32 ltr_ign;
+
+ pmc = pmcdev->pmcs[i];
+ if (!pmc)
+ continue;
+
+ guard(mutex)(&pmcdev->lock);
+ pmc->ltr_ign = pmc_core_reg_read(pmc, pmc->map->ltr_ignore_offset);
+
+ /* ltr_ignore_max is the max index value for ltr ignore register */
ltr -> LTR
Will change it in next version.
+ ltr_ign = pmc->ltr_ign | GENMASK(pmc->map->ltr_ignore_max, 0);
+ pmc_core_reg_write(pmc, pmc->map->ltr_ignore_offset, ltr_ign);
+ }
+
+ /*
+ * Ignoring ME during suspend is blocking platforms with ADL PCH to get to
+ * deeper S0IX substate.
S0ix
--
i.
Will change it in next version.
Thanks!
Xi
+ */
+ pmc_core_send_ltr_ignore(pmcdev, 6, 0);
+}
+
+static void pmc_core_ltr_restore_all(struct pmc_dev *pmcdev)
+{
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(pmcdev->pmcs); i++) {
+ struct pmc *pmc;
+
+ pmc = pmcdev->pmcs[i];
+ if (!pmc)
+ continue;
+
+ guard(mutex)(&pmcdev->lock);
+ pmc_core_reg_write(pmc, pmc->map->ltr_ignore_offset, pmc->ltr_ign);
+ }
+}
+
static inline u64 adjust_lpm_residency(struct pmc *pmc, u32 offset,
const int lpm_adj_x2)
{
@@ -1479,6 +1522,10 @@ static bool warn_on_s0ix_failures;
module_param(warn_on_s0ix_failures, bool, 0644);
MODULE_PARM_DESC(warn_on_s0ix_failures, "Check and warn for S0ix failures");
+static bool ltr_ignore_all_suspend = true;
+module_param(ltr_ignore_all_suspend, bool, 0644);
+MODULE_PARM_DESC(ltr_ignore_all_suspend, "Ignore all LTRs during suspend");
+
static __maybe_unused int pmc_core_suspend(struct device *dev)
{
struct pmc_dev *pmcdev = dev_get_drvdata(dev);
@@ -1488,6 +1535,9 @@ static __maybe_unused int pmc_core_suspend(struct device *dev)
if (pmcdev->suspend)
pmcdev->suspend(pmcdev);
+ if (ltr_ignore_all_suspend)
+ pmc_core_ltr_ignore_all(pmcdev);
+
/* Check if the syspend will actually use S0ix */
if (pm_suspend_via_firmware())
return 0;
@@ -1594,6 +1644,9 @@ static __maybe_unused int pmc_core_resume(struct device *dev)
{
struct pmc_dev *pmcdev = dev_get_drvdata(dev);
+ if (ltr_ignore_all_suspend)
+ pmc_core_ltr_restore_all(pmcdev);
+
if (pmcdev->resume)
return pmcdev->resume(pmcdev);
diff --git a/drivers/platform/x86/intel/pmc/core.h b/drivers/platform/x86/intel/pmc/core.h
index ea04de7eb9e8..e862ea88b816 100644
--- a/drivers/platform/x86/intel/pmc/core.h
+++ b/drivers/platform/x86/intel/pmc/core.h
@@ -372,6 +372,7 @@ struct pmc_info {
* @map: pointer to pmc_reg_map struct that contains platform
* specific attributes
* @lpm_req_regs: List of substate requirements
+ * @ltr_ign: Holds LTR ignore data while suspended
*
* pmc contains info about one power management controller device.
*/
@@ -380,6 +381,7 @@ struct pmc {
void __iomem *regbase;
const struct pmc_reg_map *map;
u32 *lpm_req_regs;
+ u32 ltr_ign;
};
/**
