Re: [PATCH v5 9/9] drm/xe/xe_hw_error: Add fault injection to trigger csc error handler

[Summers, Stuart]

On Tue, 2025-07-15 at 16:17 +0530, Riana Tauro wrote:
> Add a debugfs fault handler to trigger csc error handler that
> wedges the device and sends drm uevent
> 
> v2: add debugfs only for bmg (Umesh)
> 
> Signed-off-by: Riana Tauro <riana.ta...@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_debugfs.c  |  3 +++
>  drivers/gpu/drm/xe/xe_hw_error.c | 11 +++++++++++
>  2 files changed, 14 insertions(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_debugfs.c
> b/drivers/gpu/drm/xe/xe_debugfs.c
> index 26e9d146ccbf..95057c04a022 100644
> --- a/drivers/gpu/drm/xe/xe_debugfs.c
> +++ b/drivers/gpu/drm/xe/xe_debugfs.c
> @@ -31,6 +31,7 @@
>  #endif
>  
>  DECLARE_FAULT_ATTR(gt_reset_failure);
> +DECLARE_FAULT_ATTR(inject_csc_hw_error);
>  
>  static struct xe_device *node_to_xe(struct drm_info_node *node)
>  {
> @@ -294,6 +295,8 @@ void xe_debugfs_register(struct xe_device *xe)
>         xe_pxp_debugfs_register(xe->pxp);
>  
>         fault_create_debugfs_attr("fail_gt_reset", root,
> &gt_reset_failure);
> +       if (xe->info.platform == XE_BATTLEMAGE)

I'm still not clear why we need to limit this to BMG.

-Stuart

> +               fault_create_debugfs_attr("inject_csc_hw_error",
> root, &inject_csc_hw_error);
>  
>         if (IS_SRIOV_PF(xe))
>                 xe_sriov_pf_debugfs_register(xe, root);
> diff --git a/drivers/gpu/drm/xe/xe_hw_error.c
> b/drivers/gpu/drm/xe/xe_hw_error.c
> index c5b3e8c207fa..db7417c390ff 100644
> --- a/drivers/gpu/drm/xe/xe_hw_error.c
> +++ b/drivers/gpu/drm/xe/xe_hw_error.c
> @@ -3,6 +3,8 @@
>   * Copyright © 2025 Intel Corporation
>   */
>  
> +#include <linux/fault-inject.h>
> +
>  #include "regs/xe_gsc_regs.h"
>  #include "regs/xe_hw_error_regs.h"
>  #include "regs/xe_irq_regs.h"
> @@ -13,6 +15,7 @@
>  #include "xe_survivability_mode.h"
>  
>  #define  HEC_UNCORR_FW_ERR_BITS 4
> +extern struct fault_attr inject_csc_hw_error;
>  
>  /* Error categories reported by hardware */
>  enum hardware_error {
> @@ -43,6 +46,11 @@ static const char *hw_error_to_str(const enum
> hardware_error hw_err)
>         }
>  }
>  
> +static bool fault_inject_csc_hw_error(void)
> +{
> +       return should_fail(&inject_csc_hw_error, 1);
> +}
> +
>  static void csc_hw_error_work(struct work_struct *work)
>  {
>         struct xe_tile *tile = container_of(work, typeof(*tile),
> csc_hw_error_work);
> @@ -130,6 +138,9 @@ void xe_hw_error_irq_handler(struct xe_tile
> *tile, const u32 master_ctl)
>  {
>         enum hardware_error hw_err;
>  
> +       if (fault_inject_csc_hw_error())
> +               schedule_work(&tile->csc_hw_error_work);
> +
>         for (hw_err = 0; hw_err < HARDWARE_ERROR_MAX; hw_err++)
>                 if (master_ctl & ERROR_IRQ(hw_err))
>                         hw_error_source_handler(tile, hw_err);