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

From: David E. Box

Date: Thu Mar 12 2026 - 21:55:47 EST


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
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@xxxxxxxxxxxxxxx>
---
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);

--
2.43.0