[Intel-gfx] [PATCH 30/33] drm/i915: Record the RING_MODE register for post-mortem debugging

[Joonas Lahtinen]

On su, 2016-08-07 at 15:45 +0100, Chris Wilson wrote:
> Just another useful register to inspect following a GPU hang.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>  drivers/gpu/drm/i915/i915_drv.h       | 1 +
>  drivers/gpu/drm/i915/i915_gpu_error.c | 4 ++++
>  2 files changed, 5 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index e7357656728e..b5abf88e908e 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -534,6 +534,7 @@ struct drm_i915_error_state {
>  		u32 tail;
>  		u32 head;
>  		u32 ctl;
> +		u32 mode;
>  		u32 hws;
>  		u32 ipeir;
>  		u32 ipehr;
> diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
> index 5d8fd0beda2e..c48277fbe6a7 100644
> --- a/drivers/gpu/drm/i915/i915_gpu_error.c
> +++ b/drivers/gpu/drm/i915/i915_gpu_error.c
> @@ -237,6 +237,8 @@ static void error_print_engine(struct drm_i915_error_state_buf *m,
>  	err_printf(m, "  HEAD:  0x%08x\n", ee->head);
>  	err_printf(m, "  TAIL:  0x%08x\n", ee->tail);
>  	err_printf(m, "  CTL:   0x%08x\n", ee->ctl);
> +	err_printf(m, "  MODE:  0x%08x [idle? %d]\n",
> +		   ee->mode, !!(ee->mode & MODE_IDLE));

yesno()?

>  	err_printf(m, "  HWS:   0x%08x\n", ee->hws);
>  	err_printf(m, "  ACTHD: 0x%08x %08x\n",
>  		   (u32)(ee->acthd>>32), (u32)ee->acthd);
> @@ -979,6 +981,8 @@ static void error_record_engine_registers(struct drm_i915_error_state *error,
>  	ee->head = I915_READ_HEAD(engine);
>  	ee->tail = I915_READ_TAIL(engine);
>  	ee->ctl = I915_READ_CTL(engine);
> +	if (INTEL_GEN(dev_priv) > 2)
> +		ee->mode = I915_READ_MODE(engine);

IS_GEN2 is used elsewhere in the code with I915_READ_MODE, either site
should be fixed.

Regards, Joonas

>  
>  	if (I915_NEED_GFX_HWS(dev_priv)) {
>  		i915_reg_t mmio;
-- 
Joonas Lahtinen
Open Source Technology Center
Intel Corporation