[PATCH V3 11/16] platform/x86/intel/pmc/ssram: Refactor DEVID/PWRMBASE extraction into helper

David E. Box
2026-05-01T23:11:17Z

Move DEVID/PWRMBASE extraction into pmc_ssram_get_devid_pwrmbase().

This is a preparatory refactor to place functionality in a common helper
for reuse by a subsequent patch. Additionally add missing bits.h
include and define SSRAM_BASE_ADDR_MASK for the address extraction mask.

Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---
V3 - No changes

V2 changes:
- Added missing <linux/bits.h> include for GENMASK_ULL() used in get_base()
- Defined SSRAM_BASE_ADDR_MASK macro to replace magic mask constant
GENMASK_ULL(63, 3)

.../platform/x86/intel/pmc/ssram_telemetry.c | 33 ++++++++++++-------
1 file changed, 21 insertions(+), 12 deletions(-)

diff --git a/drivers/platform/x86/intel/pmc/ssram_telemetry.c b/drivers/platform/x86/intel/pmc/ssram_telemetry.c
index 4bfe60ee55ca..779e84c724ac 100644
--- a/drivers/platform/x86/intel/pmc/ssram_telemetry.c
+++ b/drivers/platform/x86/intel/pmc/ssram_telemetry.c
@@ -5,6 +5,7 @@
* Copyright (c) 2023, Intel Corporation.
*/

+#include <linux/bits.h>
#include <linux/cleanup.h>
#include <linux/intel_vsec.h>
#include <linux/pci.h>
@@ -21,12 +22,30 @@
#define SSRAM_PCH_OFFSET 0x60
#define SSRAM_IOE_OFFSET 0x68
#define SSRAM_DEVID_OFFSET 0x70
+#define SSRAM_BASE_ADDR_MASK GENMASK_ULL(63, 3)

DEFINE_FREE(pmc_ssram_telemetry_iounmap, void __iomem *, if (_T) iounmap(_T))

static struct pmc_ssram_telemetry pmc_ssram_telems[MAX_NUM_PMC];
static bool device_probed;

+static inline u64 get_base(void __iomem *addr, u32 offset)
+{
+ return lo_hi_readq(addr + offset) & SSRAM_BASE_ADDR_MASK;
+}
+
+static void pmc_ssram_get_devid_pwrmbase(void __iomem *ssram, unsigned int pmc_idx)
+{
+ u64 pwrm_base;
+ u16 devid;
+
+ pwrm_base = get_base(ssram, SSRAM_PWRM_OFFSET);
+ devid = readw(ssram + SSRAM_DEVID_OFFSET);
+
+ pmc_ssram_telems[pmc_idx].devid = devid;
+ pmc_ssram_telems[pmc_idx].base_addr = pwrm_base;
+}
+
static int
pmc_ssram_telemetry_add_pmt(struct pci_dev *pcidev, u64 ssram_base, void __iomem *ssram)
{
@@ -63,18 +82,12 @@ pmc_ssram_telemetry_add_pmt(struct pci_dev *pcidev, u64 ssram_base, void __iomem
return intel_vsec_register(&pcidev->dev, &info);
}

-static inline u64 get_base(void __iomem *addr, u32 offset)
-{
- return lo_hi_readq(addr + offset) & GENMASK_ULL(63, 3);
-}
-
static int
pmc_ssram_telemetry_get_pmc(struct pci_dev *pcidev, unsigned int pmc_idx, u32 offset)
{
void __iomem __free(pmc_ssram_telemetry_iounmap) *tmp_ssram = NULL;
void __iomem __free(pmc_ssram_telemetry_iounmap) *ssram = NULL;
- u64 ssram_base, pwrm_base;
- u16 devid;
+ u64 ssram_base;

ssram_base = pci_resource_start(pcidev, 0);
tmp_ssram = ioremap(ssram_base, SSRAM_HDR_SIZE);
@@ -99,11 +112,7 @@ pmc_ssram_telemetry_get_pmc(struct pci_dev *pcidev, unsigned int pmc_idx, u32 of
ssram = no_free_ptr(tmp_ssram);
}

- pwrm_base = get_base(ssram, SSRAM_PWRM_OFFSET);
- devid = readw(ssram + SSRAM_DEVID_OFFSET);
-
- pmc_ssram_telems[pmc_idx].devid = devid;
- pmc_ssram_telems[pmc_idx].base_addr = pwrm_base;
+ 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);
--
2.43.0