This workaround is primarily implemented by the BIOS. However if the
BIOS applies the workaround it will reserve a small piece of our DSM
(which should be at the top, right below the WOPCM); we just need to
keep that region reserved so that nothing else attempts to re-use it.
v2: Declare regs in intel_gt_regs.h (Matt Roper)
v3: Shift WA implementation before calculation of *base (Matt Roper)
Signed-off-by: Dnyaneshwar Bhadane <dnyaneshwar.bhadane@xxxxxxxxx>
---
drivers/gpu/drm/i915/gem/i915_gem_stolen.c | 17 +++++++++++++++++
drivers/gpu/drm/i915/gt/intel_gt_regs.h | 3 +++
2 files changed, 20 insertions(+)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
index 1a766d8e7cce..192c9a333c0a 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
@@ -404,6 +404,23 @@ static void icl_get_stolen_reserved(struct drm_i915_private *i915,
MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
}
+ /* Wa_14019821291 */
+ if (MEDIA_VER_FULL(i915) == IP_VER(13, 0)) {
+ /*
+ * This workaround is primarily implemented by the BIOS. We
+ * just need to figure out whether the BIOS has applied the
+ * workaround (meaning the programmed address falls within
+ * the DSM) and, if so, reserve that part of the DSM to
+ * prevent accidental reuse. The DSM location should be just
+ * below the WOPCM.
+ */
+ u64 gscpsmi_base = intel_uncore_read64_2x32(uncore,
+ MTL_GSCPSMI_BASEADDR_LSB,
+ MTL_GSCPSMI_BASEADDR_MSB);
+ if (gscpsmi_base >= *base && gscpsmi_base < *base + *size)
+ *size = gscpsmi_base - *base;
+ }
+
if (HAS_LMEMBAR_SMEM_STOLEN(i915))
/* the base is initialized to stolen top so subtract size to get base */
*base -= *size;
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_regs.h b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
index eecd0a87a647..9de41703fae5 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_regs.h
+++ b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
@@ -537,6 +537,9 @@
#define XEHP_SQCM MCR_REG(0x8724)
#define EN_32B_ACCESS REG_BIT(30)
+#define MTL_GSCPSMI_BASEADDR_LSB _MMIO(0x880c)
+#define MTL_GSCPSMI_BASEADDR_MSB _MMIO(0x8810)
+
#define HSW_IDICR _MMIO(0x9008)
#define IDIHASHMSK(x) (((x) & 0x3f) << 16)
--
2.34.1
