[Intel-xe] [PATCH 1/4] drm/xe: Return GMD_ID revid properly

[Gustavo Sousa]

Quoting Matt Roper (2023-06-14 17:51:59-03:00)
>peek_gmdid() returns the IP version, not the raw value of the GMD_ID
>register.  Make sure we extract and return the rev_id field as well so
>that it can be used to determine the IP steppings properly.

Hm... This has been fixed in a different way by Lucas in [1]. Adding him
here so we can choose one of the fixes. Both look good to me.

[1] https://patchwork.freedesktop.org/patch/542422/?series=119292&rev=1

As suggested in Lucas', I would also take this opportunity to rename
GMD_ID_REVID to GMD_ID_REVID_MASK for consistency.

Reviewed-by: Gustavo Sousa <gustavo.sousa at intel.com>

--
Gustavo Sousa

>
>Signed-off-by: Matt Roper <matthew.d.roper at intel.com>
>---
> drivers/gpu/drm/xe/xe_pci.c | 23 +++++++++++++----------
> 1 file changed, 13 insertions(+), 10 deletions(-)
>
>diff --git a/drivers/gpu/drm/xe/xe_pci.c b/drivers/gpu/drm/xe/xe_pci.c
>index 2991cf5365d5..7926c2fa1433 100644
>--- a/drivers/gpu/drm/xe/xe_pci.c
>+++ b/drivers/gpu/drm/xe/xe_pci.c
>@@ -392,23 +392,27 @@ find_subplatform(const struct xe_device *xe, const struct xe_device_desc *desc)
>         return NULL;
> }
> 
>-static u32 peek_gmdid(struct xe_device *xe, u32 gmdid_offset)
>+static void peek_gmdid(struct xe_device *xe, u32 gmdid_offset, u32 *ver, u32 *revid)
> {
>         struct pci_dev *pdev = to_pci_dev(xe->drm.dev);
>         void __iomem *map = pci_iomap_range(pdev, 0, gmdid_offset, sizeof(u32));
>-        u32 ver;
>+        u32 val;
> 
>         if (!map) {
>                 drm_err(&xe->drm, "Failed to read GMD_ID (%#x) from PCI BAR.\n",
>                         gmdid_offset);
>-                return 0;
>+                *ver = 0;
>+                *revid = 0;
>+
>+                return;
>         }
> 
>-        ver = ioread32(map);
>+        val = ioread32(map);
>         pci_iounmap(pdev, map);
> 
>-        return REG_FIELD_GET(GMD_ID_ARCH_MASK, ver) * 100 +
>-                REG_FIELD_GET(GMD_ID_RELEASE_MASK, ver);
>+        *ver = REG_FIELD_GET(GMD_ID_ARCH_MASK, val) * 100 +
>+                REG_FIELD_GET(GMD_ID_RELEASE_MASK, val);
>+        *revid = REG_FIELD_GET(GMD_ID_REVID, val);
> }
> 
> /*
>@@ -444,8 +448,7 @@ static void handle_gmdid(struct xe_device *xe,
> {
>         u32 ver;
> 
>-        ver = peek_gmdid(xe, GMD_ID.addr);
>-        *graphics_revid = REG_FIELD_GET(GMD_ID_REVID, ver);
>+        peek_gmdid(xe, GMD_ID.addr, &ver, graphics_revid);
>         for (int i = 0; i < ARRAY_SIZE(graphics_ip_map); i++) {
>                 if (ver == graphics_ip_map[i].ver) {
>                         xe->info.graphics_verx100 = ver;
>@@ -460,8 +463,8 @@ static void handle_gmdid(struct xe_device *xe,
>                         ver / 100, ver % 100);
>         }
> 
>-        ver = peek_gmdid(xe, GMD_ID.addr + 0x380000);
>-        *media_revid = REG_FIELD_GET(GMD_ID_REVID, ver);
>+        peek_gmdid(xe, GMD_ID.addr + 0x380000, &ver, media_revid);
>+
>         for (int i = 0; i < ARRAY_SIZE(media_ip_map); i++) {
>                 if (ver == media_ip_map[i].ver) {
>                         xe->info.media_verx100 = ver;
>-- 
>2.40.1
>