Re: [PATCH 21/22] platform/x86/intel/pmc/ssram: Make PMT registration optional

Ilpo Järvinen
2026-03-17T16:49:07Z

On Thu, 12 Mar 2026, David E. Box wrote:

> The SSRAM telemetry driver extracts essential PMC device ID and power
> management base address information that intel_pmc_core depends on for core
> functionality. PMT registration failure should not prevent this critical
> data from being available, as it would break intel_pmc_core operation

Are you missing a "not" here? I find the entire sentence hard to
understand.

> entirely.
>
> Change the behavior to log a warning when PMT registration fails but
> continue with successful driver initialization, ensuring the primary
> telemetry data remains accessible to dependent drivers.
>
> Signed-off-by: David E. Box <david.e.box@linux.intel.com>
> ---
> drivers/platform/x86/intel/pmc/ssram_telemetry.c | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/platform/x86/intel/pmc/ssram_telemetry.c b/drivers/platform/x86/intel/pmc/ssram_telemetry.c
> index b937ebb2322f..12b7c1299c2f 100644
> --- a/drivers/platform/x86/intel/pmc/ssram_telemetry.c
> +++ b/drivers/platform/x86/intel/pmc/ssram_telemetry.c
> @@ -106,6 +106,7 @@ pmc_ssram_telemetry_get_pmc_pci(struct pci_dev *pcidev, unsigned int pmc_idx, u3
> void __iomem __free(pmc_ssram_telemetry_iounmap) *tmp_ssram = NULL;
> void __iomem __free(pmc_ssram_telemetry_iounmap) *ssram = NULL;
> u64 ssram_base;
> + int ret;
>
> ssram_base = pci_resource_start(pcidev, 0);
> tmp_ssram = ioremap(ssram_base, SSRAM_HDR_SIZE);
> @@ -133,7 +134,11 @@ pmc_ssram_telemetry_get_pmc_pci(struct pci_dev *pcidev, unsigned int pmc_idx, u3
> pmc_ssram_get_devid_pwrmbase(ssram, pmc_idx);
>
> /* Find and register and PMC telemetry entries */
> - return pmc_ssram_telemetry_add_pmt(pcidev, ssram_base, ssram);
> + ret = pmc_ssram_telemetry_add_pmt(pcidev, ssram_base, ssram);
> + if (ret)
> + dev_warn(&pcidev->dev, "could not register PMT\n");
> +
> + return 0;
> }
>
> static int pmc_ssram_telemetry_pci_init(struct pci_dev *pcidev)
> @@ -208,12 +213,12 @@ static int pmc_ssram_telemetry_acpi_init(struct pci_dev *pcidev,
>
> ret = intel_vsec_register(&pcidev->dev, &info);
> if (ret)
> - goto cleanup_acpi_disc;
> + dev_warn(&pcidev->dev, "could not register PMT\n");
>
> ret = pmc_ssram_telemetry_get_pmc_acpi(pcidev, index);
>
> -cleanup_acpi_disc:
> kfree(acpi_disc);
> +
> cleanup_acpi_buf:
> ACPI_FREE(buf.pointer);
>
>

--
i.