diff mbox series

[PATCHv2,4/5] drm/i915/histogram: histogram delay counter doesnt reset

Message ID 20240821102349.3961986-5-arun.r.murthy@intel.com (mailing list archive)
State New, archived
Headers show
Series Display Global histogram | expand

Commit Message

Arun R Murthy Aug. 21, 2024, 10:23 a.m. UTC 
The delay counter for histogram does not reset and as a result the
histogram bin never gets updated. Woraround would be to use save and
restore histogram register.

Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
---
 drivers/gpu/drm/i915/display/intel_histogram.c | 17 +++++++++++++++++
 drivers/gpu/drm/i915/display/intel_histogram.h |  1 +
 2 files changed, 18 insertions(+)

Comments

Kandpal, Suraj Sept. 11, 2024, 10:39 a.m. UTC | #1 
> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces@lists.freedesktop.org> On Behalf Of Arun R
> Murthy
> Sent: Wednesday, August 21, 2024 3:54 PM
> To: intel-gfx@lists.freedesktop.org
> Cc: Murthy, Arun R <arun.r.murthy@intel.com>
> Subject: [PATCHv2 4/5] drm/i915/histogram: histogram delay counter doesnt
> reset
> 
> The delay counter for histogram does not reset and as a result the histogram bin
> never gets updated. Woraround would be to use save and restore histogram

Typo "Workaround"

> register.
> 
> Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_histogram.c | 17 +++++++++++++++++
> drivers/gpu/drm/i915/display/intel_histogram.h |  1 +
>  2 files changed, 18 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_histogram.c
> b/drivers/gpu/drm/i915/display/intel_histogram.c
> index ad4f75607ccb..189f7ccd6df8 100644
> --- a/drivers/gpu/drm/i915/display/intel_histogram.c
> +++ b/drivers/gpu/drm/i915/display/intel_histogram.c
> @@ -36,6 +36,11 @@ static void intel_histogram_handle_int_work(struct
> work_struct *work)
>  	u32 dpstbin;
>  	int i, try = 0;
> 
> +	/* Wa: 14014889975 */
> +	if (IS_DISPLAY_VER(i915, 12, 13))
> +		intel_de_rmw(i915, DPST_CTL(intel_crtc->pipe),
> +			     DPST_CTL_RESTORE, 0);
> +
>  	/*
>  	 * TODO: PSR to be exited while reading the Histogram data
>  	 * Set DPST_CTL Bin Reg function select to TC @@ -77,6 +82,12 @@
> static void intel_histogram_handle_int_work(struct work_struct *work)
>  			       histogram_event))
>  		drm_err(&i915->drm, "sending HISTOGRAM event failed\n");
> 
> +	/* Wa: 14014889975 */
> +	if (IS_DISPLAY_VER(i915, 12, 13))
> +		/* Write the value read from DPST_CTL to DPST_CTL.Interrupt
> Delay Counter(bit 23:16) */
> +		intel_de_write(i915, DPST_CTL(intel_crtc->pipe),
> intel_de_read(i915,
> +			       DPST_CTL(intel_crtc->pipe)) | DPST_CTL_RESTORE);
> +
>  	/* Enable histogram interrupt */
>  	intel_de_rmw(i915, DPST_GUARD(intel_crtc->pipe),
> DPST_GUARD_HIST_INT_EN,
>  		     DPST_GUARD_HIST_INT_EN);
> @@ -140,6 +151,12 @@ static int intel_histogram_enable(struct intel_crtc
> *intel_crtc)
>  	/* Pipe Dithering should be enabled with GLOBAL_HIST */
>  	intel_histogram_enable_dithering(i915, pipe);
> 
> +	/* Wa: 14014889975 */
> +	if (IS_DISPLAY_VER(i915, 12, 13))
> +		/* Write the value read from DPST_CTL to DPST_CTL.Interrupt
> Delay Counter(bit 23:16) */
> +		intel_de_write(i915, DPST_CTL(intel_crtc->pipe),
> intel_de_read(i915,
> +			       DPST_CTL(intel_crtc->pipe)) | DPST_CTL_RESTORE);
> +

Maybe put all the code in a function with required variables and one extra bool variable that determines
If it is being called when interrupt is being serviced or when histogram is being enabled

wa_14014889975(.., bool enable)
	if (!IS_DISPLAY_VER(i915, 12, 13)) /* I think there is a function that checks if display_ver is not it range to avoid the !
		return 
	if (enable)
		/* Write the value read from DPST_CTL to DPST_CTL.Interrupt
		 Delay Counter(bit 23:16) */
		intel_de_write(i915, DPST_CTL(intel_crtc->pipe),
		intel_de_read(i915,
			       DPST_CTL(intel_crtc->pipe)) | DPST_CTL_RESTORE);	
	Else
		intel_de_rmw(i915, DPST_CTL(intel_crtc->pipe),
			     DPST_CTL_RESTORE, 0);

Also use intel_display instead of i915

Regards,
Suraj Kandpal
 
>  	 * enable DPST_CTL Histogram mode
>  	 * Clear DPST_CTL Bin Reg function select to TC diff --git
> a/drivers/gpu/drm/i915/display/intel_histogram.h
> b/drivers/gpu/drm/i915/display/intel_histogram.h
> index f35ea76719d8..5e24d3c5c28b 100644
> --- a/drivers/gpu/drm/i915/display/intel_histogram.h
> +++ b/drivers/gpu/drm/i915/display/intel_histogram.h
> @@ -20,6 +20,7 @@ enum pipe;
>  #define DPST_CTL_RESTORE				REG_BIT(28)
>  #define DPST_CTL_IE_MODI_TABLE_EN			REG_BIT(27)
>  #define DPST_CTL_HIST_MODE				REG_BIT(24)
> +#define DPST_CTL_GUARDBAND_INTERRUPT_DELAY_CNT
> 	REG_GENMASK(23, 16)
>  #define DPST_CTL_ENHANCEMENT_MODE_MASK
> 	REG_GENMASK(14, 13)
>  #define DPST_CTL_EN_MULTIPLICATIVE
> 	REG_FIELD_PREP(DPST_CTL_ENHANCEMENT_MODE_MASK, 2)
>  #define DPST_CTL_IE_TABLE_VALUE_FORMAT			REG_BIT(15)
> --
> 2.25.1
Kandpal, Suraj Sept. 11, 2024, 10:41 a.m. UTC | #2 
> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces@lists.freedesktop.org> On Behalf Of Arun R
> Murthy
> Sent: Wednesday, August 21, 2024 3:54 PM
> To: intel-gfx@lists.freedesktop.org
> Cc: Murthy, Arun R <arun.r.murthy@intel.com>
> Subject: [PATCHv2 4/5] drm/i915/histogram: histogram delay counter doesnt
> reset
> 
> The delay counter for histogram does not reset and as a result the histogram bin
> never gets updated. Woraround would be to use save and restore histogram
> register.

Lets not mention the issue in the commit message just what the patch/ WA is doing
The issue is very well describe in WA no.
That's reminds me add wa no in commit message

Regards,
Suraj Kandpal
> 
> Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_histogram.c | 17 +++++++++++++++++
> drivers/gpu/drm/i915/display/intel_histogram.h |  1 +
>  2 files changed, 18 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_histogram.c
> b/drivers/gpu/drm/i915/display/intel_histogram.c
> index ad4f75607ccb..189f7ccd6df8 100644
> --- a/drivers/gpu/drm/i915/display/intel_histogram.c
> +++ b/drivers/gpu/drm/i915/display/intel_histogram.c
> @@ -36,6 +36,11 @@ static void intel_histogram_handle_int_work(struct
> work_struct *work)
>  	u32 dpstbin;
>  	int i, try = 0;
> 
> +	/* Wa: 14014889975 */
> +	if (IS_DISPLAY_VER(i915, 12, 13))
> +		intel_de_rmw(i915, DPST_CTL(intel_crtc->pipe),
> +			     DPST_CTL_RESTORE, 0);
> +
>  	/*
>  	 * TODO: PSR to be exited while reading the Histogram data
>  	 * Set DPST_CTL Bin Reg function select to TC @@ -77,6 +82,12 @@
> static void intel_histogram_handle_int_work(struct work_struct *work)
>  			       histogram_event))
>  		drm_err(&i915->drm, "sending HISTOGRAM event failed\n");
> 
> +	/* Wa: 14014889975 */
> +	if (IS_DISPLAY_VER(i915, 12, 13))
> +		/* Write the value read from DPST_CTL to DPST_CTL.Interrupt
> Delay Counter(bit 23:16) */
> +		intel_de_write(i915, DPST_CTL(intel_crtc->pipe),
> intel_de_read(i915,
> +			       DPST_CTL(intel_crtc->pipe)) | DPST_CTL_RESTORE);
> +
>  	/* Enable histogram interrupt */
>  	intel_de_rmw(i915, DPST_GUARD(intel_crtc->pipe),
> DPST_GUARD_HIST_INT_EN,
>  		     DPST_GUARD_HIST_INT_EN);
> @@ -140,6 +151,12 @@ static int intel_histogram_enable(struct intel_crtc
> *intel_crtc)
>  	/* Pipe Dithering should be enabled with GLOBAL_HIST */
>  	intel_histogram_enable_dithering(i915, pipe);
> 
> +	/* Wa: 14014889975 */
> +	if (IS_DISPLAY_VER(i915, 12, 13))
> +		/* Write the value read from DPST_CTL to DPST_CTL.Interrupt
> Delay Counter(bit 23:16) */
> +		intel_de_write(i915, DPST_CTL(intel_crtc->pipe),
> intel_de_read(i915,
> +			       DPST_CTL(intel_crtc->pipe)) | DPST_CTL_RESTORE);
> +
>  	/*
>  	 * enable DPST_CTL Histogram mode
>  	 * Clear DPST_CTL Bin Reg function select to TC diff --git
> a/drivers/gpu/drm/i915/display/intel_histogram.h
> b/drivers/gpu/drm/i915/display/intel_histogram.h
> index f35ea76719d8..5e24d3c5c28b 100644
> --- a/drivers/gpu/drm/i915/display/intel_histogram.h
> +++ b/drivers/gpu/drm/i915/display/intel_histogram.h
> @@ -20,6 +20,7 @@ enum pipe;
>  #define DPST_CTL_RESTORE				REG_BIT(28)
>  #define DPST_CTL_IE_MODI_TABLE_EN			REG_BIT(27)
>  #define DPST_CTL_HIST_MODE				REG_BIT(24)
> +#define DPST_CTL_GUARDBAND_INTERRUPT_DELAY_CNT
> 	REG_GENMASK(23, 16)
>  #define DPST_CTL_ENHANCEMENT_MODE_MASK
> 	REG_GENMASK(14, 13)
>  #define DPST_CTL_EN_MULTIPLICATIVE
> 	REG_FIELD_PREP(DPST_CTL_ENHANCEMENT_MODE_MASK, 2)
>  #define DPST_CTL_IE_TABLE_VALUE_FORMAT			REG_BIT(15)
> --
> 2.25.1
Arun R Murthy Sept. 18, 2024, 4:24 p.m. UTC | #3 
> > The delay counter for histogram does not reset and as a result the
> > histogram bin never gets updated. Woraround would be to use save and
> > restore histogram register.
> 
> Lets not mention the issue in the commit message just what the patch/ WA is
> doing The issue is very well describe in WA no.
> That's reminds me add wa no in commit message
> 
Done

Thanks and Regards,
Arun R Murthy
--------------------
Arun R Murthy Sept. 18, 2024, 4:24 p.m. UTC | #4 
> -----Original Message-----
> From: Kandpal, Suraj <suraj.kandpal@intel.com>
> Sent: Wednesday, September 11, 2024 4:10 PM
> To: Murthy, Arun R <arun.r.murthy@intel.com>; intel-gfx@lists.freedesktop.org
> Cc: Murthy, Arun R <arun.r.murthy@intel.com>
> Subject: RE: [PATCHv2 4/5] drm/i915/histogram: histogram delay counter
> doesnt reset
> 
> 
> 
> > -----Original Message-----
> > From: Intel-gfx <intel-gfx-bounces@lists.freedesktop.org> On Behalf Of
> > Arun R Murthy
> > Sent: Wednesday, August 21, 2024 3:54 PM
> > To: intel-gfx@lists.freedesktop.org
> > Cc: Murthy, Arun R <arun.r.murthy@intel.com>
> > Subject: [PATCHv2 4/5] drm/i915/histogram: histogram delay counter
> > doesnt reset
> >
> > The delay counter for histogram does not reset and as a result the
> > histogram bin never gets updated. Woraround would be to use save and
> > restore histogram
> 
> Typo "Workaround"
> 
Done

> > register.
> >
> > Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_histogram.c | 17 +++++++++++++++++
> > drivers/gpu/drm/i915/display/intel_histogram.h |  1 +
> >  2 files changed, 18 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_histogram.c
> > b/drivers/gpu/drm/i915/display/intel_histogram.c
> > index ad4f75607ccb..189f7ccd6df8 100644
> > --- a/drivers/gpu/drm/i915/display/intel_histogram.c
> > +++ b/drivers/gpu/drm/i915/display/intel_histogram.c
> > @@ -36,6 +36,11 @@ static void intel_histogram_handle_int_work(struct
> > work_struct *work)
> >  	u32 dpstbin;
> >  	int i, try = 0;
> >
> > +	/* Wa: 14014889975 */
> > +	if (IS_DISPLAY_VER(i915, 12, 13))
> > +		intel_de_rmw(i915, DPST_CTL(intel_crtc->pipe),
> > +			     DPST_CTL_RESTORE, 0);
> > +
> >  	/*
> >  	 * TODO: PSR to be exited while reading the Histogram data
> >  	 * Set DPST_CTL Bin Reg function select to TC @@ -77,6 +82,12 @@
> > static void intel_histogram_handle_int_work(struct work_struct *work)
> >  			       histogram_event))
> >  		drm_err(&i915->drm, "sending HISTOGRAM event failed\n");
> >
> > +	/* Wa: 14014889975 */
> > +	if (IS_DISPLAY_VER(i915, 12, 13))
> > +		/* Write the value read from DPST_CTL to DPST_CTL.Interrupt
> > Delay Counter(bit 23:16) */
> > +		intel_de_write(i915, DPST_CTL(intel_crtc->pipe),
> > intel_de_read(i915,
> > +			       DPST_CTL(intel_crtc->pipe)) |
> DPST_CTL_RESTORE);
> > +
> >  	/* Enable histogram interrupt */
> >  	intel_de_rmw(i915, DPST_GUARD(intel_crtc->pipe),
> > DPST_GUARD_HIST_INT_EN,
> >  		     DPST_GUARD_HIST_INT_EN);
> > @@ -140,6 +151,12 @@ static int intel_histogram_enable(struct
> > intel_crtc
> > *intel_crtc)
> >  	/* Pipe Dithering should be enabled with GLOBAL_HIST */
> >  	intel_histogram_enable_dithering(i915, pipe);
> >
> > +	/* Wa: 14014889975 */
> > +	if (IS_DISPLAY_VER(i915, 12, 13))
> > +		/* Write the value read from DPST_CTL to DPST_CTL.Interrupt
> > Delay Counter(bit 23:16) */
> > +		intel_de_write(i915, DPST_CTL(intel_crtc->pipe),
> > intel_de_read(i915,
> > +			       DPST_CTL(intel_crtc->pipe)) |
> DPST_CTL_RESTORE);
> > +
> 
> Maybe put all the code in a function with required variables and one extra bool
> variable that determines If it is being called when interrupt is being serviced or
> when histogram is being enabled
> 
Have a function to just execute one write function would be much costlier.

> wa_14014889975(.., bool enable)
> 	if (!IS_DISPLAY_VER(i915, 12, 13)) /* I think there is a function that
> checks if display_ver is not it range to avoid the !
> 		return
> 	if (enable)
> 		/* Write the value read from DPST_CTL to DPST_CTL.Interrupt
> 		 Delay Counter(bit 23:16) */
> 		intel_de_write(i915, DPST_CTL(intel_crtc->pipe),
> 		intel_de_read(i915,
> 			       DPST_CTL(intel_crtc->pipe)) |
> DPST_CTL_RESTORE);
> 	Else
> 		intel_de_rmw(i915, DPST_CTL(intel_crtc->pipe),
> 			     DPST_CTL_RESTORE, 0);
> 
> Also use intel_display instead of i915
> 
Done

Thanks and Regards,
Arun R Murthy
--------------------
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_histogram.c b/drivers/gpu/drm/i915/display/intel_histogram.c
index ad4f75607ccb..189f7ccd6df8 100644
--- a/drivers/gpu/drm/i915/display/intel_histogram.c
+++ b/drivers/gpu/drm/i915/display/intel_histogram.c
@@ -36,6 +36,11 @@  static void intel_histogram_handle_int_work(struct work_struct *work)
 	u32 dpstbin;
 	int i, try = 0;
 
+	/* Wa: 14014889975 */
+	if (IS_DISPLAY_VER(i915, 12, 13))
+		intel_de_rmw(i915, DPST_CTL(intel_crtc->pipe),
+			     DPST_CTL_RESTORE, 0);
+
 	/*
 	 * TODO: PSR to be exited while reading the Histogram data
 	 * Set DPST_CTL Bin Reg function select to TC
@@ -77,6 +82,12 @@  static void intel_histogram_handle_int_work(struct work_struct *work)
 			       histogram_event))
 		drm_err(&i915->drm, "sending HISTOGRAM event failed\n");
 
+	/* Wa: 14014889975 */
+	if (IS_DISPLAY_VER(i915, 12, 13))
+		/* Write the value read from DPST_CTL to DPST_CTL.Interrupt Delay Counter(bit 23:16) */
+		intel_de_write(i915, DPST_CTL(intel_crtc->pipe), intel_de_read(i915,
+			       DPST_CTL(intel_crtc->pipe)) | DPST_CTL_RESTORE);
+
 	/* Enable histogram interrupt */
 	intel_de_rmw(i915, DPST_GUARD(intel_crtc->pipe), DPST_GUARD_HIST_INT_EN,
 		     DPST_GUARD_HIST_INT_EN);
@@ -140,6 +151,12 @@  static int intel_histogram_enable(struct intel_crtc *intel_crtc)
 	/* Pipe Dithering should be enabled with GLOBAL_HIST */
 	intel_histogram_enable_dithering(i915, pipe);
 
+	/* Wa: 14014889975 */
+	if (IS_DISPLAY_VER(i915, 12, 13))
+		/* Write the value read from DPST_CTL to DPST_CTL.Interrupt Delay Counter(bit 23:16) */
+		intel_de_write(i915, DPST_CTL(intel_crtc->pipe), intel_de_read(i915,
+			       DPST_CTL(intel_crtc->pipe)) | DPST_CTL_RESTORE);
+
 	/*
 	 * enable DPST_CTL Histogram mode
 	 * Clear DPST_CTL Bin Reg function select to TC
diff --git a/drivers/gpu/drm/i915/display/intel_histogram.h b/drivers/gpu/drm/i915/display/intel_histogram.h
index f35ea76719d8..5e24d3c5c28b 100644
--- a/drivers/gpu/drm/i915/display/intel_histogram.h
+++ b/drivers/gpu/drm/i915/display/intel_histogram.h
@@ -20,6 +20,7 @@  enum pipe;
 #define DPST_CTL_RESTORE				REG_BIT(28)
 #define DPST_CTL_IE_MODI_TABLE_EN			REG_BIT(27)
 #define DPST_CTL_HIST_MODE				REG_BIT(24)
+#define DPST_CTL_GUARDBAND_INTERRUPT_DELAY_CNT		REG_GENMASK(23, 16)
 #define DPST_CTL_ENHANCEMENT_MODE_MASK			REG_GENMASK(14, 13)
 #define DPST_CTL_EN_MULTIPLICATIVE			REG_FIELD_PREP(DPST_CTL_ENHANCEMENT_MODE_MASK, 2)
 #define DPST_CTL_IE_TABLE_VALUE_FORMAT			REG_BIT(15)