[PATCH v2 4/4] drm/xe/pf: Handle MERT catastrophic errors

[Lukasz Laguna <lukasz.laguna@intel.com>]

The MERT block triggers an interrupt when a catastrophic error occurs.
Update the interrupt handler to read the MERT catastrophic error type
and log appropriate debug message.

Signed-off-by: Lukasz Laguna <lukasz.laguna@intel.com>
---
v2:
 - rebase,
 - fix the VF ID extraction from the read value.
---
 drivers/gpu/drm/xe/regs/xe_mert_regs.h |  5 +++++
 drivers/gpu/drm/xe/xe_mert.c           | 11 +++++++++++
 2 files changed, 16 insertions(+)

diff --git a/drivers/gpu/drm/xe/regs/xe_mert_regs.h b/drivers/gpu/drm/xe/regs/xe_mert_regs.h
index aef66c04901d..c345e11ceea8 100644
--- a/drivers/gpu/drm/xe/regs/xe_mert_regs.h
+++ b/drivers/gpu/drm/xe/regs/xe_mert_regs.h
@@ -10,6 +10,11 @@
 
 #define MERT_LMEM_CFG				XE_REG(0x1448b0)
 
+#define MERT_TLB_CT_INTR_ERR_ID_PORT		XE_REG(0x145190)
+#define   MERT_TLB_CT_VFID_MASK			REG_GENMASK(16, 9)
+#define   MERT_TLB_CT_ERROR_MASK		REG_GENMASK(5, 0)
+#define     MERT_TLB_CT_LMTT_FAULT		0x05
+
 #define MERT_TLB_INV_DESC_A			XE_REG(0x14cf7c)
 #define   MERT_TLB_INV_DESC_A_VALID		REG_BIT(0)
 
diff --git a/drivers/gpu/drm/xe/xe_mert.c b/drivers/gpu/drm/xe/xe_mert.c
index 304cc8421999..e5e0ad872506 100644
--- a/drivers/gpu/drm/xe/xe_mert.c
+++ b/drivers/gpu/drm/xe/xe_mert.c
@@ -55,10 +55,21 @@ void xe_mert_irq_handler(struct xe_device *xe, u32 master_ctl)
 	struct xe_tile *tile = xe_device_get_root_tile(xe);
 	unsigned long flags;
 	u32 reg_val;
+	u8 err;
 
 	if (!(master_ctl & SOC_H2DMEMINT_IRQ))
 		return;
 
+	reg_val = xe_mmio_read32(&tile->mmio, MERT_TLB_CT_INTR_ERR_ID_PORT);
+	xe_mmio_write32(&tile->mmio, MERT_TLB_CT_INTR_ERR_ID_PORT, 0);
+
+	err = reg_val & MERT_TLB_CT_ERROR_MASK;
+	if (err == MERT_TLB_CT_LMTT_FAULT)
+		drm_dbg(&xe->drm, "MERT catastrophic error: LMTT fault (VF%u)\n",
+			FIELD_GET(MERT_TLB_CT_VFID_MASK, reg_val));
+	else if (err)
+		drm_dbg(&xe->drm, "MERT catastrophic error: Unexpected fault (0x%x)\n", err);
+
 	spin_lock_irqsave(&tile->mert.lock, flags);
 	if (tile->mert.tlb_inv_triggered) {
 		reg_val = xe_mmio_read32(&tile->mmio, MERT_TLB_INV_DESC_A);
-- 
2.40.0