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[PATCH v2 3/6] media: mali-c55: Fully reset the ISP configuration

Jacopo Mondi posted 6 patches 3 weeks, 3 days ago
[PATCH v2 3/6] media: mali-c55: Fully reset the ISP configuration
Posted by Jacopo Mondi 3 weeks, 3 days ago 
The Mali C55 driver uses an auto-suspend delay of 2000 milli-seconds.

As the delay is quite large, it is certainly possible that two
consecutive calls to enable_streams() do not go through a suspend of the
peripheral, meaning we cannot rely on POW register values for the ISP
configuration.

To prevent a streaming session to be initialized with settings from the
previous one, reset the full ISP configuration to know state disabling or
bypassing all the ISP blocks the driver supports.

Cc: stable@vger.kernel.org
Fixes: d5f281f3dd29 ("media: mali-c55: Add Mali-C55 ISP driver")
Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
---
 .../media/platform/arm/mali-c55/mali-c55-params.c  | 50 ++++++++++++++++++++++
 1 file changed, 50 insertions(+)

diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-params.c b/drivers/media/platform/arm/mali-c55/mali-c55-params.c
index c84a6047a570..773e5b6a2b7e 100644
--- a/drivers/media/platform/arm/mali-c55/mali-c55-params.c
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-params.c
@@ -781,6 +781,43 @@ void mali_c55_params_init_isp_config(struct mali_c55 *mali_c55,
 				 MALI_C55_REG_BYPASS_3_SQUARE_BE,
 				 MALI_C55_REG_BYPASS_3_SQUARE_BE);
 
+	/* Bypass the sensor offset correction (BLS) module */
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_BYPASS_3,
+		MALI_C55_REG_BYPASS_3_SENSOR_OFFSET_PRE_SH,
+		MALI_C55_REG_BYPASS_3_SENSOR_OFFSET_PRE_SH);
+
+	/* Configure 1x digital gain. */
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_DIGITAL_GAIN,
+				 MALI_C55_DIGITAL_GAIN_MASK, 256);
+
+	/* Set all AWB gains to 1x. at both AWB configuration points*/
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS1,
+				 MALI_C55_AWB_GAIN00_MASK, 256);
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS1,
+				 MALI_C55_AWB_GAIN01_MASK,
+				 MALI_C55_AWB_GAIN01(256));
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS2,
+				 MALI_C55_AWB_GAIN10_MASK, 256);
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS2,
+				 MALI_C55_AWB_GAIN11_MASK,
+				 MALI_C55_AWB_GAIN11(256));
+
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS1_AEXP,
+				 MALI_C55_AWB_GAIN00_MASK, 256);
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS1_AEXP,
+				 MALI_C55_AWB_GAIN01_MASK,
+				 MALI_C55_AWB_GAIN01(256));
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS2_AEXP,
+				 MALI_C55_AWB_GAIN10_MASK, 256);
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS2_AEXP,
+				 MALI_C55_AWB_GAIN11_MASK,
+				 MALI_C55_AWB_GAIN11(256));
+
+	/* Bypass mesh shading corrections (LSC). */
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_MESH_SHADING_CONFIG,
+				 MALI_C55_MESH_SHADING_ENABLE_MASK,
+				 false);
+
 	/* Bypass the temper module */
 	mali_c55_ctx_write(mali_c55, MALI_C55_REG_BYPASS_2,
 			   MALI_C55_REG_BYPASS_2_TEMPER);
@@ -802,6 +839,19 @@ void mali_c55_params_init_isp_config(struct mali_c55 *mali_c55,
 
 	/* Disable the colour correction matrix */
 	mali_c55_ctx_write(mali_c55, MALI_C55_REG_CCM_ENABLE, 0);
+
+	/* Disable AWB stats. */
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_METERING_CONFIG,
+				 MALI_C55_AWB_DISABLE_MASK,
+				 MALI_C55_AWB_DISABLE_MASK);
+
+	/* Disable auto-exposure 1024-bin histograms at both tap points. */
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_METERING_CONFIG,
+				 MALI_C55_AEXP_HIST_DISABLE_MASK,
+				 MALI_C55_AEXP_HIST_DISABLE);
+	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_METERING_CONFIG,
+				 MALI_C55_AEXP_IHIST_DISABLE_MASK,
+				 MALI_C55_AEXP_IHIST_DISABLE);
 }
 
 void mali_c55_unregister_params(struct mali_c55 *mali_c55)

-- 
2.53.0
Re: [PATCH v2 3/6] media: mali-c55: Fully reset the ISP configuration
Posted by Dan Scally 3 weeks, 3 days ago 
Hi Jacopo

On 13/03/2026 14:53, Jacopo Mondi wrote:
> The Mali C55 driver uses an auto-suspend delay of 2000 milli-seconds.
> 
> As the delay is quite large, it is certainly possible that two
> consecutive calls to enable_streams() do not go through a suspend of the
> peripheral, meaning we cannot rely on POW register values for the ISP
> configuration.
> 
> To prevent a streaming session to be initialized with settings from the
> previous one, reset the full ISP configuration to know state disabling or
> bypassing all the ISP blocks the driver supports.

Oh that's annoying - good spot...perhaps the auto-suspend delay should be reduced too, though I 
think this change is prudent anyway:

Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>

> 
> Cc: stable@vger.kernel.org
> Fixes: d5f281f3dd29 ("media: mali-c55: Add Mali-C55 ISP driver")
> Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
> ---
>   .../media/platform/arm/mali-c55/mali-c55-params.c  | 50 ++++++++++++++++++++++
>   1 file changed, 50 insertions(+)
> 
> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-params.c b/drivers/media/platform/arm/mali-c55/mali-c55-params.c
> index c84a6047a570..773e5b6a2b7e 100644
> --- a/drivers/media/platform/arm/mali-c55/mali-c55-params.c
> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-params.c
> @@ -781,6 +781,43 @@ void mali_c55_params_init_isp_config(struct mali_c55 *mali_c55,
>   				 MALI_C55_REG_BYPASS_3_SQUARE_BE,
>   				 MALI_C55_REG_BYPASS_3_SQUARE_BE);
>   
> +	/* Bypass the sensor offset correction (BLS) module */
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_BYPASS_3,
> +		MALI_C55_REG_BYPASS_3_SENSOR_OFFSET_PRE_SH,
> +		MALI_C55_REG_BYPASS_3_SENSOR_OFFSET_PRE_SH);
> +
> +	/* Configure 1x digital gain. */
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_DIGITAL_GAIN,
> +				 MALI_C55_DIGITAL_GAIN_MASK, 256);
> +
> +	/* Set all AWB gains to 1x. at both AWB configuration points*/
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS1,
> +				 MALI_C55_AWB_GAIN00_MASK, 256);
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS1,
> +				 MALI_C55_AWB_GAIN01_MASK,
> +				 MALI_C55_AWB_GAIN01(256));
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS2,
> +				 MALI_C55_AWB_GAIN10_MASK, 256);
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS2,
> +				 MALI_C55_AWB_GAIN11_MASK,
> +				 MALI_C55_AWB_GAIN11(256));
> +
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS1_AEXP,
> +				 MALI_C55_AWB_GAIN00_MASK, 256);
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS1_AEXP,
> +				 MALI_C55_AWB_GAIN01_MASK,
> +				 MALI_C55_AWB_GAIN01(256));
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS2_AEXP,
> +				 MALI_C55_AWB_GAIN10_MASK, 256);
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_AWB_GAINS2_AEXP,
> +				 MALI_C55_AWB_GAIN11_MASK,
> +				 MALI_C55_AWB_GAIN11(256));
> +
> +	/* Bypass mesh shading corrections (LSC). */
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_MESH_SHADING_CONFIG,
> +				 MALI_C55_MESH_SHADING_ENABLE_MASK,
> +				 false);
> +
>   	/* Bypass the temper module */
>   	mali_c55_ctx_write(mali_c55, MALI_C55_REG_BYPASS_2,
>   			   MALI_C55_REG_BYPASS_2_TEMPER);
> @@ -802,6 +839,19 @@ void mali_c55_params_init_isp_config(struct mali_c55 *mali_c55,
>   
>   	/* Disable the colour correction matrix */
>   	mali_c55_ctx_write(mali_c55, MALI_C55_REG_CCM_ENABLE, 0);
> +
> +	/* Disable AWB stats. */
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_METERING_CONFIG,
> +				 MALI_C55_AWB_DISABLE_MASK,
> +				 MALI_C55_AWB_DISABLE_MASK);
> +
> +	/* Disable auto-exposure 1024-bin histograms at both tap points. */
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_METERING_CONFIG,
> +				 MALI_C55_AEXP_HIST_DISABLE_MASK,
> +				 MALI_C55_AEXP_HIST_DISABLE);
> +	mali_c55_ctx_update_bits(mali_c55, MALI_C55_REG_METERING_CONFIG,
> +				 MALI_C55_AEXP_IHIST_DISABLE_MASK,
> +				 MALI_C55_AEXP_IHIST_DISABLE);
>   }
>   
>   void mali_c55_unregister_params(struct mali_c55 *mali_c55)
>

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