Re: [PATCH v4 1/1] drm/xe/guc: Add Wa_14025883347 for GuC DMA failure on reset

["Nilawar, Badal" <badal.nilawar@intel.com>]

On 02-02-2026 16:23, Sk Anirban wrote:
> Prevent GuC firmware DMA failures during GuC-only reset by disabling
> idle flow and verifying SRAM handling completion. Without this, reset
> can be issued while SRAM handler is copying WOPCM to SRAM,
> causing GuC HW to get stuck.
>
> v2: Modify error message (Badal)
>      Rename reg bit name (Daniele)
>      Update WA skip condition (Daniele)
>      Update SRAM handling logic (Daniele)
> v3: Reorder WA call (Badal)
>      Wait for GuC ready status (Daniele)
> v4: Update reg name (Badal)
>      Add comment (Daniele)
>      Add extended graphics version (Daniele)
>      Modify rules
>
> Signed-off-by: Sk Anirban <sk.anirban@intel.com>

LGTM
Reviewed-by: Badal Nilawar <badal.nilawar@intel.com>

Thanks,
Badal

> ---
>   drivers/gpu/drm/xe/regs/xe_guc_regs.h |  8 ++++++
>   drivers/gpu/drm/xe/xe_guc.c           | 38 +++++++++++++++++++++++++++
>   drivers/gpu/drm/xe/xe_wa_oob.rules    |  3 +++
>   3 files changed, 49 insertions(+)
>
> diff --git a/drivers/gpu/drm/xe/regs/xe_guc_regs.h b/drivers/gpu/drm/xe/regs/xe_guc_regs.h
> index 87984713dd12..5faac8316b66 100644
> --- a/drivers/gpu/drm/xe/regs/xe_guc_regs.h
> +++ b/drivers/gpu/drm/xe/regs/xe_guc_regs.h
> @@ -40,6 +40,9 @@
>   #define   GS_BOOTROM_JUMP_PASSED		REG_FIELD_PREP(GS_BOOTROM_MASK, 0x76)
>   #define   GS_MIA_IN_RESET			REG_BIT(0)
>   
> +#define BOOT_HASH_CHK				XE_REG(0xc010)
> +#define   GUC_BOOT_UKERNEL_VALID		REG_BIT(31)
> +
>   #define GUC_HEADER_INFO				XE_REG(0xc014)
>   
>   #define GUC_WOPCM_SIZE				XE_REG(0xc050)
> @@ -83,7 +86,12 @@
>   #define   GUC_WOPCM_OFFSET_MASK			REG_GENMASK(31, GUC_WOPCM_OFFSET_SHIFT)
>   #define   HUC_LOADING_AGENT_GUC			REG_BIT(1)
>   #define   GUC_WOPCM_OFFSET_VALID		REG_BIT(0)
> +
> +#define GUC_SRAM_STATUS				XE_REG(0xc398)
> +#define   GUC_SRAM_HANDLING_MASK		REG_GENMASK(8, 7)
> +
>   #define GUC_MAX_IDLE_COUNT			XE_REG(0xc3e4)
> +#define   GUC_IDLE_FLOW_DISABLE			REG_BIT(31)
>   #define GUC_PMTIMESTAMP_LO			XE_REG(0xc3e8)
>   #define GUC_PMTIMESTAMP_HI			XE_REG(0xc3ec)
>   
> diff --git a/drivers/gpu/drm/xe/xe_guc.c b/drivers/gpu/drm/xe/xe_guc.c
> index 2efc4678fa73..369b5a8f129a 100644
> --- a/drivers/gpu/drm/xe/xe_guc.c
> +++ b/drivers/gpu/drm/xe/xe_guc.c
> @@ -911,6 +911,41 @@ int xe_guc_post_load_init(struct xe_guc *guc)
>   	return xe_guc_submit_enable(guc);
>   }
>   
> +/*
> + * Wa_14025883347: Prevent GuC firmware DMA failures during GuC-only reset by ensuring
> + * SRAM save/restore operations are complete before reset.
> + */
> +static void guc_prevent_fw_dma_failure_on_reset(struct xe_guc *guc)
> +{
> +	struct xe_gt *gt = guc_to_gt(guc);
> +	u32 boot_hash_chk, guc_status, sram_status;
> +	int ret;
> +
> +	guc_status = xe_mmio_read32(&gt->mmio, GUC_STATUS);
> +	if (guc_status & GS_MIA_IN_RESET)
> +		return;
> +
> +	boot_hash_chk = xe_mmio_read32(&gt->mmio, BOOT_HASH_CHK);
> +	if (!(boot_hash_chk & GUC_BOOT_UKERNEL_VALID))
> +		return;
> +
> +	/* Disable idle flow during reset (GuC reset re-enables it automatically) */
> +	xe_mmio_rmw32(&gt->mmio, GUC_MAX_IDLE_COUNT, 0, GUC_IDLE_FLOW_DISABLE);
> +
> +	ret = xe_mmio_wait32(&gt->mmio, GUC_STATUS, GS_UKERNEL_MASK,
> +			     FIELD_PREP(GS_UKERNEL_MASK, XE_GUC_LOAD_STATUS_READY),
> +			     100000, &guc_status, false);
> +	if (ret)
> +		xe_gt_warn(gt, "GuC not ready after disabling idle flow (GUC_STATUS: 0x%x)\n",
> +			   guc_status);
> +
> +	ret = xe_mmio_wait32(&gt->mmio, GUC_SRAM_STATUS, GUC_SRAM_HANDLING_MASK,
> +			     0, 5000, &sram_status, false);
> +	if (ret)
> +		xe_gt_warn(gt, "SRAM handling not complete (GUC_SRAM_STATUS: 0x%x)\n",
> +			   sram_status);
> +}
> +
>   int xe_guc_reset(struct xe_guc *guc)
>   {
>   	struct xe_gt *gt = guc_to_gt(guc);
> @@ -923,6 +958,9 @@ int xe_guc_reset(struct xe_guc *guc)
>   	if (IS_SRIOV_VF(gt_to_xe(gt)))
>   		return xe_gt_sriov_vf_bootstrap(gt);
>   
> +	if (XE_GT_WA(gt, 14025883347))
> +		guc_prevent_fw_dma_failure_on_reset(guc);
> +
>   	xe_mmio_write32(mmio, GDRST, GRDOM_GUC);
>   
>   	ret = xe_mmio_wait32(mmio, GDRST, GRDOM_GUC, 0, 5000, &gdrst, false);
> diff --git a/drivers/gpu/drm/xe/xe_wa_oob.rules b/drivers/gpu/drm/xe/xe_wa_oob.rules
> index 5cd7fa6d2a5c..ac08f94f90a1 100644
> --- a/drivers/gpu/drm/xe/xe_wa_oob.rules
> +++ b/drivers/gpu/drm/xe/xe_wa_oob.rules
> @@ -73,3 +73,6 @@
>   15015404425_disable	PLATFORM(PANTHERLAKE), MEDIA_STEP(B0, FOREVER)
>   16026007364    MEDIA_VERSION(3000)
>   14020316580    MEDIA_VERSION(1301)
> +
> +14025883347	MEDIA_VERSION_RANGE(1301, 3503)
> +		GRAPHICS_VERSION_RANGE(2004, 3005)