Re: [PATCH V2 11/17] platform/x86/intel/pmc/ssram: Refactor DEVID/PWRMBASE extraction into helper

Ilpo Järvinen
2026-04-07T13:18:35Z

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On Tue, 24 Mar 2026, David E. Box wrote:

> 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>
> ---
>
> 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);
>

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

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