[PATCH] platform/x86/intel/pmc: Use each PMC's own status map on S0ix failure

[PATCH] platform/x86/intel/pmc: Use each PMC's own status map on S0ix failure

[Cole Leavitt]

When S0ix entry fails and warn_on_s0ix_failures is set,
pmc_core_resume_common() dumps the latched LPM status registers of every
PMC.  The loop over pmcdev->pmcs[] however passes the register offset and
bit maps of the main PMC to pmc_core_lpm_display() for all of them, so
the registers of the secondary PMCs are read at the main PMC's offset
and decoded with the main PMC's bit names.  On platforms with more than
one PMC, such as Arrow Lake-HX with an 800 series PCH, the dump
attributes the PCH's power gating state to the wrong IP blocks, which
makes it useless for finding the device that blocks S0ix.

Use the status offset and maps of the PMC being displayed.

Fixes: 2bcef4529222 ("platform/x86:intel/pmc: Enable debugfs multiple PMC support")
Signed-off-by: Cole Leavitt <cole@unwrap.rs>
---

Notes:
    Tested on a Lenovo ThinkPad P16 Gen 3 (Core Ultra 9 275HX, JHL9580
    Barlow Ridge host, I226 Ethernet), in daily use since 2026-09-17.

 drivers/platform/x86/intel/pmc/core.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/platform/x86/intel/pmc/core.c b/drivers/platform/x86/intel/pmc/core.c
index 9f77c0716e59..3fd72e6a08ce 100644
--- a/drivers/platform/x86/intel/pmc/core.c
+++ b/drivers/platform/x86/intel/pmc/core.c
@@ -2068,8 +2068,6 @@ int pmc_core_resume_common(struct pmc_dev *pmcdev)
 {
 	struct device *dev = &pmcdev->pdev->dev;
 	struct pmc *pmc = pmcdev->pmcs[PMC_IDX_MAIN];
-	const struct pmc_bit_map **maps = pmc->map->lpm_sts;
-	int offset = pmc->map->lpm_status_offset;
 	unsigned int pmc_idx, i;
 
 	/* Check if the syspend used S0ix */
@@ -2114,7 +2112,9 @@ int pmc_core_resume_common(struct pmc_dev *pmcdev)
 		if (!pmc)
 			continue;
 		if (pmc->map->lpm_sts)
-			pmc_core_lpm_display(pmc, dev, NULL, offset, pmc_idx, "STATUS", maps);
+			pmc_core_lpm_display(pmc, dev, NULL,
+					     pmc->map->lpm_status_offset,
+					     pmc_idx, "STATUS", pmc->map->lpm_sts);
 	}
 
 	return 0;

base-commit: 32c52ec87d6245ee2d12ed5dd509e40062939b50
-- 
2.54.0

Re: [PATCH] platform/x86/intel/pmc: Use each PMC's own status map on S0ix failure

[Ilpo Järvinen]

On Sun, 18 Oct 2026, Cole Leavitt wrote:

> When S0ix entry fails and warn_on_s0ix_failures is set,
> pmc_core_resume_common() dumps the latched LPM status registers of every
> PMC.  The loop over pmcdev->pmcs[] however passes the register offset and

One space is enough.

> bit maps of the main PMC to pmc_core_lpm_display() for all of them, so
> the registers of the secondary PMCs are read at the main PMC's offset
> and decoded with the main PMC's bit names.  On platforms with more than
> one PMC, such as Arrow Lake-HX with an 800 series PCH, the dump
> attributes the PCH's power gating state to the wrong IP blocks, which
> makes it useless for finding the device that blocks S0ix.
> 
> Use the status offset and maps of the PMC being displayed.
> 
> Fixes: 2bcef4529222 ("platform/x86:intel/pmc: Enable debugfs multiple PMC support")
> Signed-off-by: Cole Leavitt <cole@unwrap.rs>
> ---
> 
> Notes:
>     Tested on a Lenovo ThinkPad P16 Gen 3 (Core Ultra 9 275HX, JHL9580
>     Barlow Ridge host, I226 Ethernet), in daily use since 2026-09-17.
> 
>  drivers/platform/x86/intel/pmc/core.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/platform/x86/intel/pmc/core.c b/drivers/platform/x86/intel/pmc/core.c
> index 9f77c0716e59..3fd72e6a08ce 100644
> --- a/drivers/platform/x86/intel/pmc/core.c
> +++ b/drivers/platform/x86/intel/pmc/core.c
> @@ -2068,8 +2068,6 @@ int pmc_core_resume_common(struct pmc_dev *pmcdev)
>  {
>  	struct device *dev = &pmcdev->pdev->dev;
>  	struct pmc *pmc = pmcdev->pmcs[PMC_IDX_MAIN];
> -	const struct pmc_bit_map **maps = pmc->map->lpm_sts;
> -	int offset = pmc->map->lpm_status_offset;
>  	unsigned int pmc_idx, i;
>  
>  	/* Check if the syspend used S0ix */
> @@ -2114,7 +2112,9 @@ int pmc_core_resume_common(struct pmc_dev *pmcdev)
>  		if (!pmc)
>  			continue;
>  		if (pmc->map->lpm_sts)
> -			pmc_core_lpm_display(pmc, dev, NULL, offset, pmc_idx, "STATUS", maps);
> +			pmc_core_lpm_display(pmc, dev, NULL,
> +					     pmc->map->lpm_status_offset,
> +					     pmc_idx, "STATUS", pmc->map->lpm_sts);

This looks good finding but I suggest you use intermediate variables 
similar to what the other callers of pmc_core_lpm_display() do. It would 
also allow converting that if check to use the same local var.

-- 
 i.