[PATCH V6 13/20] platform/x86/intel/pmc: Cleanup SSRAM discovery

David E. Box
2023-11-29T22:21:43Z

Clean up the code handling SSRAM discovery. Handle all resource allocation
and cleanup in pmc_core_ssram_get_pmc(). Return the error status from this
function but only fail the init if we fail to discover the primary PMC.

Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---
V6 - Drops patch adding cleanup helpers for iounmap() and ioport_unmap()
to io.h until s390 build issue is resolved. Add pmc_core specific
DEFINE_FREE helper for iounmap() for now.

V5 - Use single function to handle SSRAM discovery of all PMCs.

V4 - Add checking the return value from pmc_core_sram_init() to mtl.c
- Use iounmap cleanup from io.h

V3 - New patch split from previous PATCH 2
- Update changelog
- Use cleanup.h to cleanup ioremap

V2 - no change

drivers/platform/x86/intel/pmc/core_ssram.c | 62 +++++++++++----------
1 file changed, 33 insertions(+), 29 deletions(-)

diff --git a/drivers/platform/x86/intel/pmc/core_ssram.c b/drivers/platform/x86/intel/pmc/core_ssram.c
index 815950713e25..c1b984255571 100644
--- a/drivers/platform/x86/intel/pmc/core_ssram.c
+++ b/drivers/platform/x86/intel/pmc/core_ssram.c
@@ -8,6 +8,7 @@
*
*/

+#include <linux/cleanup.h>
#include <linux/pci.h>
#include <linux/io-64-nonatomic-lo-hi.h>

@@ -21,6 +22,8 @@
#define SSRAM_IOE_OFFSET 0x68
#define SSRAM_DEVID_OFFSET 0x70

+DEFINE_FREE(pmc_core_iounmap, void __iomem *, iounmap(_T));
+
static const struct pmc_reg_map *pmc_core_find_regmap(struct pmc_info *list, u16 devid)
{
for (; list->map; ++list)
@@ -65,44 +68,49 @@ pmc_core_pmc_add(struct pmc_dev *pmcdev, u64 pwrm_base,
return 0;
}

-static void
-pmc_core_ssram_get_pmc(struct pmc_dev *pmcdev, void __iomem *ssram, u32 offset,
- int pmc_idx)
+static int
+pmc_core_ssram_get_pmc(struct pmc_dev *pmcdev, int pmc_idx, u32 offset)
{
- u64 pwrm_base;
+ struct pci_dev *ssram_pcidev = pmcdev->ssram_pcidev;
+ void __iomem __free(pmc_core_iounmap) *tmp_ssram = NULL;
+ void __iomem __free(pmc_core_iounmap) *ssram = NULL;
+ const struct pmc_reg_map *map;
+ u64 ssram_base, pwrm_base;
u16 devid;

- if (pmc_idx != PMC_IDX_SOC) {
- u64 ssram_base = get_base(ssram, offset);
+ if (!pmcdev->regmap_list)
+ return -ENOENT;

- if (!ssram_base)
- return;
+ ssram_base = ssram_pcidev->resource[0].start;
+ tmp_ssram = ioremap(ssram_base, SSRAM_HDR_SIZE);

+ if (pmc_idx != PMC_IDX_MAIN) {
+ /*
+ * The secondary PMC BARS (which are behind hidden PCI devices)
+ * are read from fixed offsets in MMIO of the primary PMC BAR.
+ */
+ ssram_base = get_base(tmp_ssram, offset);
ssram = ioremap(ssram_base, SSRAM_HDR_SIZE);
if (!ssram)
- return;
+ return -ENOMEM;
+
+ } else {
+ ssram = no_free_ptr(tmp_ssram);
}

pwrm_base = get_base(ssram, SSRAM_PWRM_OFFSET);
devid = readw(ssram + SSRAM_DEVID_OFFSET);

- if (pmcdev->regmap_list) {
- const struct pmc_reg_map *map;
+ map = pmc_core_find_regmap(pmcdev->regmap_list, devid);
+ if (!map)
+ return -ENODEV;

- map = pmc_core_find_regmap(pmcdev->regmap_list, devid);
- if (map)
- pmc_core_pmc_add(pmcdev, pwrm_base, map, pmc_idx);
- }
-
- if (pmc_idx != PMC_IDX_SOC)
- iounmap(ssram);
+ return pmc_core_pmc_add(pmcdev, pwrm_base, map, PMC_IDX_MAIN);
}

int pmc_core_ssram_init(struct pmc_dev *pmcdev)
{
- void __iomem *ssram;
struct pci_dev *pcidev;
- u64 ssram_base;
int ret;

pcidev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(20, 2));
@@ -113,18 +121,14 @@ int pmc_core_ssram_init(struct pmc_dev *pmcdev)
if (ret)
goto release_dev;

- ssram_base = pcidev->resource[0].start;
- ssram = ioremap(ssram_base, SSRAM_HDR_SIZE);
- if (!ssram)
- goto disable_dev;
-
pmcdev->ssram_pcidev = pcidev;

- pmc_core_ssram_get_pmc(pmcdev, ssram, 0, PMC_IDX_SOC);
- pmc_core_ssram_get_pmc(pmcdev, ssram, SSRAM_IOE_OFFSET, PMC_IDX_IOE);
- pmc_core_ssram_get_pmc(pmcdev, ssram, SSRAM_PCH_OFFSET, PMC_IDX_PCH);
+ ret = pmc_core_ssram_get_pmc(pmcdev, PMC_IDX_MAIN, 0);
+ if (ret)
+ goto disable_dev;

- iounmap(ssram);
+ pmc_core_ssram_get_pmc(pmcdev, PMC_IDX_IOE, SSRAM_IOE_OFFSET);
+ pmc_core_ssram_get_pmc(pmcdev, PMC_IDX_PCH, SSRAM_PCH_OFFSET);

return 0;

--
2.34.1