From: Jayesh Choudhary <j-choudhary@ti.com>

The TIDSS hardware does not have independent maximum or minimum pixel
clock limits for each video port. Instead, these limits are determined
by the SoC's clock architecture. Previously, this constraint was
modeled using the 'max_pclk_khz' and 'min_pclk_khz' fields in
'dispc_features', but this approach is static and does not account for
the dynamic behavior of PLLs.

This patch removes the 'max_pclk_khz' and 'min_pclk_khz' fields from
'dispc_features'. The correct way to check if a requested mode's pixel
clock is supported is by using 'clk_round_rate()' in the 'mode_valid()'
hook. If the best frequency match for the mode clock falls within the
supported tolerance, it is approved. TIDSS supports a 5% pixel clock
tolerance, which is now reflected in the validation logic.

This change allows existing DSS-compatible drivers to be reused across
SoCs that only differ in their pixel clock characteristics. The
validation uses 'clk_round_rate()' for each mode, which may introduce
additional delay (about 3.5 ms for 30 modes), but this is generally
negligible. Users desiring faster validation may bypass these calls
selectively, for example, checking only the highest resolution mode,
as shown here[1].

[1]: https://lore.kernel.org/all/20250704094851.182131-3-j-choudhary@ti.com/

Tested-by: Michael Walle <mwalle@kernel.org>
Reviewed-by: Devarsh Thakkar <devarsht@ti.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
Signed-off-by: Swamil Jain <s-jain1@ti.com>
---
 drivers/gpu/drm/tidss/tidss_dispc.c | 86 +++++++++++------------------
 drivers/gpu/drm/tidss/tidss_dispc.h |  3 -
 2 files changed, 31 insertions(+), 58 deletions(-)

diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/tidss/tidss_dispc.c
index d0b191c470ca..b11880178cba 100644
--- a/drivers/gpu/drm/tidss/tidss_dispc.c
+++ b/drivers/gpu/drm/tidss/tidss_dispc.c
@@ -57,12 +57,6 @@ static const u16 tidss_k2g_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
 };
 
 const struct dispc_features dispc_k2g_feats = {
-	.min_pclk_khz = 4375,
-
-	.max_pclk_khz = {
-		[DISPC_VP_DPI] = 150000,
-	},
-
 	/*
 	 * XXX According TRM the RGB input buffer width up to 2560 should
 	 *     work on 3 taps, but in practice it only works up to 1280.
@@ -145,11 +139,6 @@ static const u16 tidss_am65x_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
 };
 
 const struct dispc_features dispc_am65x_feats = {
-	.max_pclk_khz = {
-		[DISPC_VP_DPI] = 165000,
-		[DISPC_VP_OLDI_AM65X] = 165000,
-	},
-
 	.scaling = {
 		.in_width_max_5tap_rgb = 1280,
 		.in_width_max_3tap_rgb = 2560,
@@ -245,11 +234,6 @@ static const u16 tidss_j721e_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
 };
 
 const struct dispc_features dispc_j721e_feats = {
-	.max_pclk_khz = {
-		[DISPC_VP_DPI] = 170000,
-		[DISPC_VP_INTERNAL] = 600000,
-	},
-
 	.scaling = {
 		.in_width_max_5tap_rgb = 2048,
 		.in_width_max_3tap_rgb = 4096,
@@ -316,11 +300,6 @@ const struct dispc_features dispc_j721e_feats = {
 };
 
 const struct dispc_features dispc_am625_feats = {
-	.max_pclk_khz = {
-		[DISPC_VP_DPI] = 165000,
-		[DISPC_VP_INTERNAL] = 170000,
-	},
-
 	.scaling = {
 		.in_width_max_5tap_rgb = 1280,
 		.in_width_max_3tap_rgb = 2560,
@@ -377,15 +356,6 @@ const struct dispc_features dispc_am625_feats = {
 };
 
 const struct dispc_features dispc_am62a7_feats = {
-	/*
-	 * if the code reaches dispc_mode_valid with VP1,
-	 * it should return MODE_BAD.
-	 */
-	.max_pclk_khz = {
-		[DISPC_VP_TIED_OFF] = 0,
-		[DISPC_VP_DPI] = 165000,
-	},
-
 	.scaling = {
 		.in_width_max_5tap_rgb = 1280,
 		.in_width_max_3tap_rgb = 2560,
@@ -442,10 +412,6 @@ const struct dispc_features dispc_am62a7_feats = {
 };
 
 const struct dispc_features dispc_am62l_feats = {
-	.max_pclk_khz = {
-		[DISPC_VP_DPI] = 165000,
-	},
-
 	.subrev = DISPC_AM62L,
 
 	.common = "common",
@@ -1333,33 +1299,54 @@ static void dispc_vp_set_default_color(struct dispc_device *dispc,
 			DISPC_OVR_DEFAULT_COLOR2, (v >> 32) & 0xffff);
 }
 
+/*
+ * Calculate the percentage difference between the requested pixel clock rate
+ * and the effective rate resulting from calculating the clock divider value.
+ */
+unsigned int dispc_pclk_diff(unsigned long rate, unsigned long real_rate)
+{
+	int r = rate / 100, rr = real_rate / 100;
+
+	return (unsigned int)(abs(((rr - r) * 100) / r));
+}
+
+static inline int check_pixel_clock(struct dispc_device *dispc,
+			     u32 hw_videoport, unsigned long clock)
+{
+	unsigned long round_clock;
+
+	round_clock = clk_round_rate(dispc->vp_clk[hw_videoport], clock);
+	/*
+	 * To keep the check consistent with dispc_vp_set_clk_rate(), we
+	 * use the same 5% check here.
+	 */
+	if (dispc_pclk_diff(clock, round_clock) > 5)
+		return -EINVAL;
+
+	return 0;
+}
+
 enum drm_mode_status dispc_vp_mode_valid(struct dispc_device *dispc,
 					 u32 hw_videoport,
 					 const struct drm_display_mode *mode)
 {
 	u32 hsw, hfp, hbp, vsw, vfp, vbp;
 	enum dispc_vp_bus_type bus_type;
-	int max_pclk;
 
 	bus_type = dispc->feat->vp_bus_type[hw_videoport];
 
-	max_pclk = dispc->feat->max_pclk_khz[bus_type];
-
-	if (WARN_ON(max_pclk == 0))
+	if (WARN_ON(bus_type == DISPC_VP_TIED_OFF))
 		return MODE_BAD;
 
-	if (mode->clock < dispc->feat->min_pclk_khz)
-		return MODE_CLOCK_LOW;
-
-	if (mode->clock > max_pclk)
-		return MODE_CLOCK_HIGH;
-
 	if (mode->hdisplay > 4096)
 		return MODE_BAD;
 
 	if (mode->vdisplay > 4096)
 		return MODE_BAD;
 
+	if (check_pixel_clock(dispc, hw_videoport, mode->clock * 1000))
+		return MODE_CLOCK_RANGE;
+
 	/* TODO: add interlace support */
 	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
 		return MODE_NO_INTERLACE;
@@ -1423,17 +1410,6 @@ void dispc_vp_disable_clk(struct dispc_device *dispc, u32 hw_videoport)
 	clk_disable_unprepare(dispc->vp_clk[hw_videoport]);
 }
 
-/*
- * Calculate the percentage difference between the requested pixel clock rate
- * and the effective rate resulting from calculating the clock divider value.
- */
-unsigned int dispc_pclk_diff(unsigned long rate, unsigned long real_rate)
-{
-	int r = rate / 100, rr = real_rate / 100;
-
-	return (unsigned int)(abs(((rr - r) * 100) / r));
-}
-
 int dispc_vp_set_clk_rate(struct dispc_device *dispc, u32 hw_videoport,
 			  unsigned long rate)
 {
diff --git a/drivers/gpu/drm/tidss/tidss_dispc.h b/drivers/gpu/drm/tidss/tidss_dispc.h
index 60c1b400eb89..42279312dcc1 100644
--- a/drivers/gpu/drm/tidss/tidss_dispc.h
+++ b/drivers/gpu/drm/tidss/tidss_dispc.h
@@ -77,9 +77,6 @@ enum dispc_dss_subrevision {
 };
 
 struct dispc_features {
-	int min_pclk_khz;
-	int max_pclk_khz[DISPC_VP_MAX_BUS_TYPE];
-
 	struct dispc_features_scaling scaling;
 
 	enum dispc_dss_subrevision subrev;

Hi,

On 04/11/2025 17:14, Swamil Jain wrote:
> From: Jayesh Choudhary <j-choudhary@ti.com>
> 
> The TIDSS hardware does not have independent maximum or minimum pixel
> clock limits for each video port. Instead, these limits are determined
> by the SoC's clock architecture. Previously, this constraint was
> modeled using the 'max_pclk_khz' and 'min_pclk_khz' fields in
> 'dispc_features', but this approach is static and does not account for
> the dynamic behavior of PLLs.
> 
> This patch removes the 'max_pclk_khz' and 'min_pclk_khz' fields from
> 'dispc_features'. The correct way to check if a requested mode's pixel
> clock is supported is by using 'clk_round_rate()' in the 'mode_valid()'
> hook. If the best frequency match for the mode clock falls within the
> supported tolerance, it is approved. TIDSS supports a 5% pixel clock
> tolerance, which is now reflected in the validation logic.
> 
> This change allows existing DSS-compatible drivers to be reused across
> SoCs that only differ in their pixel clock characteristics. The
> validation uses 'clk_round_rate()' for each mode, which may introduce
> additional delay (about 3.5 ms for 30 modes), but this is generally
> negligible. Users desiring faster validation may bypass these calls
> selectively, for example, checking only the highest resolution mode,
> as shown here[1].
> 
> [1]: https://lore.kernel.org/all/20250704094851.182131-3-j-choudhary@ti.com/
> 
> Tested-by: Michael Walle <mwalle@kernel.org>
> Reviewed-by: Devarsh Thakkar <devarsht@ti.com>
> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
> Signed-off-by: Swamil Jain <s-jain1@ti.com>
> ---
>  drivers/gpu/drm/tidss/tidss_dispc.c | 86 +++++++++++------------------
>  drivers/gpu/drm/tidss/tidss_dispc.h |  3 -
>  2 files changed, 31 insertions(+), 58 deletions(-)
> 
> diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/tidss/tidss_dispc.c
> index d0b191c470ca..b11880178cba 100644
> --- a/drivers/gpu/drm/tidss/tidss_dispc.c
> +++ b/drivers/gpu/drm/tidss/tidss_dispc.c
> @@ -57,12 +57,6 @@ static const u16 tidss_k2g_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
>  };
>  
>  const struct dispc_features dispc_k2g_feats = {
> -	.min_pclk_khz = 4375,
> -
> -	.max_pclk_khz = {
> -		[DISPC_VP_DPI] = 150000,
> -	},
> -
>  	/*
>  	 * XXX According TRM the RGB input buffer width up to 2560 should
>  	 *     work on 3 taps, but in practice it only works up to 1280.
> @@ -145,11 +139,6 @@ static const u16 tidss_am65x_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
>  };
>  
>  const struct dispc_features dispc_am65x_feats = {
> -	.max_pclk_khz = {
> -		[DISPC_VP_DPI] = 165000,
> -		[DISPC_VP_OLDI_AM65X] = 165000,
> -	},
> -
>  	.scaling = {
>  		.in_width_max_5tap_rgb = 1280,
>  		.in_width_max_3tap_rgb = 2560,
> @@ -245,11 +234,6 @@ static const u16 tidss_j721e_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
>  };
>  
>  const struct dispc_features dispc_j721e_feats = {
> -	.max_pclk_khz = {
> -		[DISPC_VP_DPI] = 170000,
> -		[DISPC_VP_INTERNAL] = 600000,
> -	},
> -
>  	.scaling = {
>  		.in_width_max_5tap_rgb = 2048,
>  		.in_width_max_3tap_rgb = 4096,
> @@ -316,11 +300,6 @@ const struct dispc_features dispc_j721e_feats = {
>  };
>  
>  const struct dispc_features dispc_am625_feats = {
> -	.max_pclk_khz = {
> -		[DISPC_VP_DPI] = 165000,
> -		[DISPC_VP_INTERNAL] = 170000,
> -	},
> -
>  	.scaling = {
>  		.in_width_max_5tap_rgb = 1280,
>  		.in_width_max_3tap_rgb = 2560,
> @@ -377,15 +356,6 @@ const struct dispc_features dispc_am625_feats = {
>  };
>  
>  const struct dispc_features dispc_am62a7_feats = {
> -	/*
> -	 * if the code reaches dispc_mode_valid with VP1,
> -	 * it should return MODE_BAD.
> -	 */
> -	.max_pclk_khz = {
> -		[DISPC_VP_TIED_OFF] = 0,
> -		[DISPC_VP_DPI] = 165000,
> -	},
> -
>  	.scaling = {
>  		.in_width_max_5tap_rgb = 1280,
>  		.in_width_max_3tap_rgb = 2560,
> @@ -442,10 +412,6 @@ const struct dispc_features dispc_am62a7_feats = {
>  };
>  
>  const struct dispc_features dispc_am62l_feats = {
> -	.max_pclk_khz = {
> -		[DISPC_VP_DPI] = 165000,
> -	},
> -
>  	.subrev = DISPC_AM62L,
>  
>  	.common = "common",
> @@ -1333,33 +1299,54 @@ static void dispc_vp_set_default_color(struct dispc_device *dispc,
>  			DISPC_OVR_DEFAULT_COLOR2, (v >> 32) & 0xffff);
>  }
>  
> +/*
> + * Calculate the percentage difference between the requested pixel clock rate
> + * and the effective rate resulting from calculating the clock divider value.
> + */
> +unsigned int dispc_pclk_diff(unsigned long rate, unsigned long real_rate)
> +{
> +	int r = rate / 100, rr = real_rate / 100;
> +
> +	return (unsigned int)(abs(((rr - r) * 100) / r));
> +}
> +
> +static inline int check_pixel_clock(struct dispc_device *dispc,
> +			     u32 hw_videoport, unsigned long clock)
> +{

Ah... Sorry, I was quite unclear in my comment to v7. I did not mean
mark it as inline. I meant "move it inline", i.e. move this code into
the dispc_vp_mode_valid function. This is just a few lines, and having
it in a separate function makes it a bit more difficult to understand
what are all the checks done in dispc_vp_mode_valid().

I can do that change when applying the patches, if that's ok for you.

 Tomi

> +	unsigned long round_clock;
> +
> +	round_clock = clk_round_rate(dispc->vp_clk[hw_videoport], clock);
> +	/*
> +	 * To keep the check consistent with dispc_vp_set_clk_rate(), we
> +	 * use the same 5% check here.
> +	 */
> +	if (dispc_pclk_diff(clock, round_clock) > 5)
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +
>  enum drm_mode_status dispc_vp_mode_valid(struct dispc_device *dispc,
>  					 u32 hw_videoport,
>  					 const struct drm_display_mode *mode)
>  {
>  	u32 hsw, hfp, hbp, vsw, vfp, vbp;
>  	enum dispc_vp_bus_type bus_type;
> -	int max_pclk;
>  
>  	bus_type = dispc->feat->vp_bus_type[hw_videoport];
>  
> -	max_pclk = dispc->feat->max_pclk_khz[bus_type];
> -
> -	if (WARN_ON(max_pclk == 0))
> +	if (WARN_ON(bus_type == DISPC_VP_TIED_OFF))
>  		return MODE_BAD;
>  
> -	if (mode->clock < dispc->feat->min_pclk_khz)
> -		return MODE_CLOCK_LOW;
> -
> -	if (mode->clock > max_pclk)
> -		return MODE_CLOCK_HIGH;
> -
>  	if (mode->hdisplay > 4096)
>  		return MODE_BAD;
>  
>  	if (mode->vdisplay > 4096)
>  		return MODE_BAD;
>  
> +	if (check_pixel_clock(dispc, hw_videoport, mode->clock * 1000))
> +		return MODE_CLOCK_RANGE;
> +
>  	/* TODO: add interlace support */
>  	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
>  		return MODE_NO_INTERLACE;
> @@ -1423,17 +1410,6 @@ void dispc_vp_disable_clk(struct dispc_device *dispc, u32 hw_videoport)
>  	clk_disable_unprepare(dispc->vp_clk[hw_videoport]);
>  }
>  
> -/*
> - * Calculate the percentage difference between the requested pixel clock rate
> - * and the effective rate resulting from calculating the clock divider value.
> - */
> -unsigned int dispc_pclk_diff(unsigned long rate, unsigned long real_rate)
> -{
> -	int r = rate / 100, rr = real_rate / 100;
> -
> -	return (unsigned int)(abs(((rr - r) * 100) / r));
> -}
> -
>  int dispc_vp_set_clk_rate(struct dispc_device *dispc, u32 hw_videoport,
>  			  unsigned long rate)
>  {
> diff --git a/drivers/gpu/drm/tidss/tidss_dispc.h b/drivers/gpu/drm/tidss/tidss_dispc.h
> index 60c1b400eb89..42279312dcc1 100644
> --- a/drivers/gpu/drm/tidss/tidss_dispc.h
> +++ b/drivers/gpu/drm/tidss/tidss_dispc.h
> @@ -77,9 +77,6 @@ enum dispc_dss_subrevision {
>  };
>  
>  struct dispc_features {
> -	int min_pclk_khz;
> -	int max_pclk_khz[DISPC_VP_MAX_BUS_TYPE];
> -
>  	struct dispc_features_scaling scaling;
>  
>  	enum dispc_dss_subrevision subrev;

Hi Tomi,

On 11/12/25 15:10, Tomi Valkeinen wrote:
> Hi,
> 
> On 04/11/2025 17:14, Swamil Jain wrote:
>> From: Jayesh Choudhary <j-choudhary@ti.com>
>>
>> The TIDSS hardware does not have independent maximum or minimum pixel
>> clock limits for each video port. Instead, these limits are determined
>> by the SoC's clock architecture. Previously, this constraint was
>> modeled using the 'max_pclk_khz' and 'min_pclk_khz' fields in
>> 'dispc_features', but this approach is static and does not account for
>> the dynamic behavior of PLLs.
>>
>> This patch removes the 'max_pclk_khz' and 'min_pclk_khz' fields from
>> 'dispc_features'. The correct way to check if a requested mode's pixel
>> clock is supported is by using 'clk_round_rate()' in the 'mode_valid()'
>> hook. If the best frequency match for the mode clock falls within the
>> supported tolerance, it is approved. TIDSS supports a 5% pixel clock
>> tolerance, which is now reflected in the validation logic.
>>
>> This change allows existing DSS-compatible drivers to be reused across
>> SoCs that only differ in their pixel clock characteristics. The
>> validation uses 'clk_round_rate()' for each mode, which may introduce
>> additional delay (about 3.5 ms for 30 modes), but this is generally
>> negligible. Users desiring faster validation may bypass these calls
>> selectively, for example, checking only the highest resolution mode,
>> as shown here[1].
>>
>> [1]: https://lore.kernel.org/all/20250704094851.182131-3-j-choudhary@ti.com/
>>
>> Tested-by: Michael Walle <mwalle@kernel.org>
>> Reviewed-by: Devarsh Thakkar <devarsht@ti.com>
>> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
>> Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
>> Signed-off-by: Swamil Jain <s-jain1@ti.com>
>> ---
>>   drivers/gpu/drm/tidss/tidss_dispc.c | 86 +++++++++++------------------
>>   drivers/gpu/drm/tidss/tidss_dispc.h |  3 -
>>   2 files changed, 31 insertions(+), 58 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/tidss/tidss_dispc.c
>> index d0b191c470ca..b11880178cba 100644
>> --- a/drivers/gpu/drm/tidss/tidss_dispc.c
>> +++ b/drivers/gpu/drm/tidss/tidss_dispc.c
>> @@ -57,12 +57,6 @@ static const u16 tidss_k2g_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
>>   };
>>   
>>   const struct dispc_features dispc_k2g_feats = {
>> -	.min_pclk_khz = 4375,
>> -
>> -	.max_pclk_khz = {
>> -		[DISPC_VP_DPI] = 150000,
>> -	},
>> -
>>   	/*
>>   	 * XXX According TRM the RGB input buffer width up to 2560 should
>>   	 *     work on 3 taps, but in practice it only works up to 1280.
>> @@ -145,11 +139,6 @@ static const u16 tidss_am65x_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
>>   };
>>   
>>   const struct dispc_features dispc_am65x_feats = {
>> -	.max_pclk_khz = {
>> -		[DISPC_VP_DPI] = 165000,
>> -		[DISPC_VP_OLDI_AM65X] = 165000,
>> -	},
>> -
>>   	.scaling = {
>>   		.in_width_max_5tap_rgb = 1280,
>>   		.in_width_max_3tap_rgb = 2560,
>> @@ -245,11 +234,6 @@ static const u16 tidss_j721e_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
>>   };
>>   
>>   const struct dispc_features dispc_j721e_feats = {
>> -	.max_pclk_khz = {
>> -		[DISPC_VP_DPI] = 170000,
>> -		[DISPC_VP_INTERNAL] = 600000,
>> -	},
>> -
>>   	.scaling = {
>>   		.in_width_max_5tap_rgb = 2048,
>>   		.in_width_max_3tap_rgb = 4096,
>> @@ -316,11 +300,6 @@ const struct dispc_features dispc_j721e_feats = {
>>   };
>>   
>>   const struct dispc_features dispc_am625_feats = {
>> -	.max_pclk_khz = {
>> -		[DISPC_VP_DPI] = 165000,
>> -		[DISPC_VP_INTERNAL] = 170000,
>> -	},
>> -
>>   	.scaling = {
>>   		.in_width_max_5tap_rgb = 1280,
>>   		.in_width_max_3tap_rgb = 2560,
>> @@ -377,15 +356,6 @@ const struct dispc_features dispc_am625_feats = {
>>   };
>>   
>>   const struct dispc_features dispc_am62a7_feats = {
>> -	/*
>> -	 * if the code reaches dispc_mode_valid with VP1,
>> -	 * it should return MODE_BAD.
>> -	 */
>> -	.max_pclk_khz = {
>> -		[DISPC_VP_TIED_OFF] = 0,
>> -		[DISPC_VP_DPI] = 165000,
>> -	},
>> -
>>   	.scaling = {
>>   		.in_width_max_5tap_rgb = 1280,
>>   		.in_width_max_3tap_rgb = 2560,
>> @@ -442,10 +412,6 @@ const struct dispc_features dispc_am62a7_feats = {
>>   };
>>   
>>   const struct dispc_features dispc_am62l_feats = {
>> -	.max_pclk_khz = {
>> -		[DISPC_VP_DPI] = 165000,
>> -	},
>> -
>>   	.subrev = DISPC_AM62L,
>>   
>>   	.common = "common",
>> @@ -1333,33 +1299,54 @@ static void dispc_vp_set_default_color(struct dispc_device *dispc,
>>   			DISPC_OVR_DEFAULT_COLOR2, (v >> 32) & 0xffff);
>>   }
>>   
>> +/*
>> + * Calculate the percentage difference between the requested pixel clock rate
>> + * and the effective rate resulting from calculating the clock divider value.
>> + */
>> +unsigned int dispc_pclk_diff(unsigned long rate, unsigned long real_rate)
>> +{
>> +	int r = rate / 100, rr = real_rate / 100;
>> +
>> +	return (unsigned int)(abs(((rr - r) * 100) / r));
>> +}
>> +
>> +static inline int check_pixel_clock(struct dispc_device *dispc,
>> +			     u32 hw_videoport, unsigned long clock)
>> +{
> 
> Ah... Sorry, I was quite unclear in my comment to v7. I did not mean
> mark it as inline. I meant "move it inline", i.e. move this code into
> the dispc_vp_mode_valid function. This is just a few lines, and having
> it in a separate function makes it a bit more difficult to understand
> what are all the checks done in dispc_vp_mode_valid().
> 
> I can do that change when applying the patches, if that's ok for you.
> 

Thanks Tomi, please do the required changes.

Regards,
Swamil

>   Tomi
> 
>> +	unsigned long round_clock;
>> +
>> +	round_clock = clk_round_rate(dispc->vp_clk[hw_videoport], clock);
>> +	/*
>> +	 * To keep the check consistent with dispc_vp_set_clk_rate(), we
>> +	 * use the same 5% check here.
>> +	 */
>> +	if (dispc_pclk_diff(clock, round_clock) > 5)
>> +		return -EINVAL;
>> +
>> +	return 0;
>> +}
>> +
>>   enum drm_mode_status dispc_vp_mode_valid(struct dispc_device *dispc,
>>   					 u32 hw_videoport,
>>   					 const struct drm_display_mode *mode)
>>   {
>>   	u32 hsw, hfp, hbp, vsw, vfp, vbp;
>>   	enum dispc_vp_bus_type bus_type;
>> -	int max_pclk;
>>   
>>   	bus_type = dispc->feat->vp_bus_type[hw_videoport];
>>   
>> -	max_pclk = dispc->feat->max_pclk_khz[bus_type];
>> -
>> -	if (WARN_ON(max_pclk == 0))
>> +	if (WARN_ON(bus_type == DISPC_VP_TIED_OFF))
>>   		return MODE_BAD;
>>   
>> -	if (mode->clock < dispc->feat->min_pclk_khz)
>> -		return MODE_CLOCK_LOW;
>> -
>> -	if (mode->clock > max_pclk)
>> -		return MODE_CLOCK_HIGH;
>> -
>>   	if (mode->hdisplay > 4096)
>>   		return MODE_BAD;
>>   
>>   	if (mode->vdisplay > 4096)
>>   		return MODE_BAD;
>>   
>> +	if (check_pixel_clock(dispc, hw_videoport, mode->clock * 1000))
>> +		return MODE_CLOCK_RANGE;
>> +
>>   	/* TODO: add interlace support */
>>   	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
>>   		return MODE_NO_INTERLACE;
>> @@ -1423,17 +1410,6 @@ void dispc_vp_disable_clk(struct dispc_device *dispc, u32 hw_videoport)
>>   	clk_disable_unprepare(dispc->vp_clk[hw_videoport]);
>>   }
>>   
>> -/*
>> - * Calculate the percentage difference between the requested pixel clock rate
>> - * and the effective rate resulting from calculating the clock divider value.
>> - */
>> -unsigned int dispc_pclk_diff(unsigned long rate, unsigned long real_rate)
>> -{
>> -	int r = rate / 100, rr = real_rate / 100;
>> -
>> -	return (unsigned int)(abs(((rr - r) * 100) / r));
>> -}
>> -
>>   int dispc_vp_set_clk_rate(struct dispc_device *dispc, u32 hw_videoport,
>>   			  unsigned long rate)
>>   {
>> diff --git a/drivers/gpu/drm/tidss/tidss_dispc.h b/drivers/gpu/drm/tidss/tidss_dispc.h
>> index 60c1b400eb89..42279312dcc1 100644
>> --- a/drivers/gpu/drm/tidss/tidss_dispc.h
>> +++ b/drivers/gpu/drm/tidss/tidss_dispc.h
>> @@ -77,9 +77,6 @@ enum dispc_dss_subrevision {
>>   };
>>   
>>   struct dispc_features {
>> -	int min_pclk_khz;
>> -	int max_pclk_khz[DISPC_VP_MAX_BUS_TYPE];
>> -
>>   	struct dispc_features_scaling scaling;
>>   
>>   	enum dispc_dss_subrevision subrev;
>

Hi,

On 12/11/2025 11:43, Swamil Jain wrote:
> Hi Tomi,
> 
> On 11/12/25 15:10, Tomi Valkeinen wrote:
>> Hi,
>>
>> On 04/11/2025 17:14, Swamil Jain wrote:
>>> From: Jayesh Choudhary <j-choudhary@ti.com>
>>>
>>> The TIDSS hardware does not have independent maximum or minimum pixel
>>> clock limits for each video port. Instead, these limits are determined
>>> by the SoC's clock architecture. Previously, this constraint was
>>> modeled using the 'max_pclk_khz' and 'min_pclk_khz' fields in
>>> 'dispc_features', but this approach is static and does not account for
>>> the dynamic behavior of PLLs.
>>>
>>> This patch removes the 'max_pclk_khz' and 'min_pclk_khz' fields from
>>> 'dispc_features'. The correct way to check if a requested mode's pixel
>>> clock is supported is by using 'clk_round_rate()' in the 'mode_valid()'
>>> hook. If the best frequency match for the mode clock falls within the
>>> supported tolerance, it is approved. TIDSS supports a 5% pixel clock
>>> tolerance, which is now reflected in the validation logic.
>>>
>>> This change allows existing DSS-compatible drivers to be reused across
>>> SoCs that only differ in their pixel clock characteristics. The
>>> validation uses 'clk_round_rate()' for each mode, which may introduce
>>> additional delay (about 3.5 ms for 30 modes), but this is generally
>>> negligible. Users desiring faster validation may bypass these calls
>>> selectively, for example, checking only the highest resolution mode,
>>> as shown here[1].
>>>
>>> [1]: https://lore.kernel.org/all/20250704094851.182131-3-j-
>>> choudhary@ti.com/
>>>
>>> Tested-by: Michael Walle <mwalle@kernel.org>
>>> Reviewed-by: Devarsh Thakkar <devarsht@ti.com>
>>> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
>>> Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
>>> Signed-off-by: Swamil Jain <s-jain1@ti.com>
>>> ---
>>>   drivers/gpu/drm/tidss/tidss_dispc.c | 86 +++++++++++------------------
>>>   drivers/gpu/drm/tidss/tidss_dispc.h |  3 -
>>>   2 files changed, 31 insertions(+), 58 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/
>>> tidss/tidss_dispc.c
>>> index d0b191c470ca..b11880178cba 100644
>>> --- a/drivers/gpu/drm/tidss/tidss_dispc.c
>>> +++ b/drivers/gpu/drm/tidss/tidss_dispc.c
>>> @@ -57,12 +57,6 @@ static const u16
>>> tidss_k2g_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
>>>   };
>>>     const struct dispc_features dispc_k2g_feats = {
>>> -    .min_pclk_khz = 4375,
>>> -
>>> -    .max_pclk_khz = {
>>> -        [DISPC_VP_DPI] = 150000,
>>> -    },
>>> -
>>>       /*
>>>        * XXX According TRM the RGB input buffer width up to 2560 should
>>>        *     work on 3 taps, but in practice it only works up to 1280.
>>> @@ -145,11 +139,6 @@ static const u16
>>> tidss_am65x_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
>>>   };
>>>     const struct dispc_features dispc_am65x_feats = {
>>> -    .max_pclk_khz = {
>>> -        [DISPC_VP_DPI] = 165000,
>>> -        [DISPC_VP_OLDI_AM65X] = 165000,
>>> -    },
>>> -
>>>       .scaling = {
>>>           .in_width_max_5tap_rgb = 1280,
>>>           .in_width_max_3tap_rgb = 2560,
>>> @@ -245,11 +234,6 @@ static const u16
>>> tidss_j721e_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
>>>   };
>>>     const struct dispc_features dispc_j721e_feats = {
>>> -    .max_pclk_khz = {
>>> -        [DISPC_VP_DPI] = 170000,
>>> -        [DISPC_VP_INTERNAL] = 600000,
>>> -    },
>>> -
>>>       .scaling = {
>>>           .in_width_max_5tap_rgb = 2048,
>>>           .in_width_max_3tap_rgb = 4096,
>>> @@ -316,11 +300,6 @@ const struct dispc_features dispc_j721e_feats = {
>>>   };
>>>     const struct dispc_features dispc_am625_feats = {
>>> -    .max_pclk_khz = {
>>> -        [DISPC_VP_DPI] = 165000,
>>> -        [DISPC_VP_INTERNAL] = 170000,
>>> -    },
>>> -
>>>       .scaling = {
>>>           .in_width_max_5tap_rgb = 1280,
>>>           .in_width_max_3tap_rgb = 2560,
>>> @@ -377,15 +356,6 @@ const struct dispc_features dispc_am625_feats = {
>>>   };
>>>     const struct dispc_features dispc_am62a7_feats = {
>>> -    /*
>>> -     * if the code reaches dispc_mode_valid with VP1,
>>> -     * it should return MODE_BAD.
>>> -     */
>>> -    .max_pclk_khz = {
>>> -        [DISPC_VP_TIED_OFF] = 0,
>>> -        [DISPC_VP_DPI] = 165000,
>>> -    },
>>> -
>>>       .scaling = {
>>>           .in_width_max_5tap_rgb = 1280,
>>>           .in_width_max_3tap_rgb = 2560,
>>> @@ -442,10 +412,6 @@ const struct dispc_features dispc_am62a7_feats = {
>>>   };
>>>     const struct dispc_features dispc_am62l_feats = {
>>> -    .max_pclk_khz = {
>>> -        [DISPC_VP_DPI] = 165000,
>>> -    },
>>> -
>>>       .subrev = DISPC_AM62L,
>>>         .common = "common",
>>> @@ -1333,33 +1299,54 @@ static void dispc_vp_set_default_color(struct
>>> dispc_device *dispc,
>>>               DISPC_OVR_DEFAULT_COLOR2, (v >> 32) & 0xffff);
>>>   }
>>>   +/*
>>> + * Calculate the percentage difference between the requested pixel
>>> clock rate
>>> + * and the effective rate resulting from calculating the clock
>>> divider value.
>>> + */
>>> +unsigned int dispc_pclk_diff(unsigned long rate, unsigned long
>>> real_rate)
>>> +{
>>> +    int r = rate / 100, rr = real_rate / 100;
>>> +
>>> +    return (unsigned int)(abs(((rr - r) * 100) / r));
>>> +}
>>> +
>>> +static inline int check_pixel_clock(struct dispc_device *dispc,
>>> +                 u32 hw_videoport, unsigned long clock)
>>> +{
>>
>> Ah... Sorry, I was quite unclear in my comment to v7. I did not mean
>> mark it as inline. I meant "move it inline", i.e. move this code into
>> the dispc_vp_mode_valid function. This is just a few lines, and having
>> it in a separate function makes it a bit more difficult to understand
>> what are all the checks done in dispc_vp_mode_valid().
>>
>> I can do that change when applying the patches, if that's ok for you.
>>
> 
> Thanks Tomi, please do the required changes.

Actually, now that I was about to do the change, I realized the next
patch adds an if check here. So maybe it's better to keep it as a
separate function. I'll just drop the "inline".

 Tomi

> 
> Regards,
> Swamil
> 
>>   Tomi
>>
>>> +    unsigned long round_clock;
>>> +
>>> +    round_clock = clk_round_rate(dispc->vp_clk[hw_videoport], clock);
>>> +    /*
>>> +     * To keep the check consistent with dispc_vp_set_clk_rate(), we
>>> +     * use the same 5% check here.
>>> +     */
>>> +    if (dispc_pclk_diff(clock, round_clock) > 5)
>>> +        return -EINVAL;
>>> +
>>> +    return 0;
>>> +}
>>> +
>>>   enum drm_mode_status dispc_vp_mode_valid(struct dispc_device *dispc,
>>>                        u32 hw_videoport,
>>>                        const struct drm_display_mode *mode)
>>>   {
>>>       u32 hsw, hfp, hbp, vsw, vfp, vbp;
>>>       enum dispc_vp_bus_type bus_type;
>>> -    int max_pclk;
>>>         bus_type = dispc->feat->vp_bus_type[hw_videoport];
>>>   -    max_pclk = dispc->feat->max_pclk_khz[bus_type];
>>> -
>>> -    if (WARN_ON(max_pclk == 0))
>>> +    if (WARN_ON(bus_type == DISPC_VP_TIED_OFF))
>>>           return MODE_BAD;
>>>   -    if (mode->clock < dispc->feat->min_pclk_khz)
>>> -        return MODE_CLOCK_LOW;
>>> -
>>> -    if (mode->clock > max_pclk)
>>> -        return MODE_CLOCK_HIGH;
>>> -
>>>       if (mode->hdisplay > 4096)
>>>           return MODE_BAD;
>>>         if (mode->vdisplay > 4096)
>>>           return MODE_BAD;
>>>   +    if (check_pixel_clock(dispc, hw_videoport, mode->clock * 1000))
>>> +        return MODE_CLOCK_RANGE;
>>> +
>>>       /* TODO: add interlace support */
>>>       if (mode->flags & DRM_MODE_FLAG_INTERLACE)
>>>           return MODE_NO_INTERLACE;
>>> @@ -1423,17 +1410,6 @@ void dispc_vp_disable_clk(struct dispc_device
>>> *dispc, u32 hw_videoport)
>>>       clk_disable_unprepare(dispc->vp_clk[hw_videoport]);
>>>   }
>>>   -/*
>>> - * Calculate the percentage difference between the requested pixel
>>> clock rate
>>> - * and the effective rate resulting from calculating the clock
>>> divider value.
>>> - */
>>> -unsigned int dispc_pclk_diff(unsigned long rate, unsigned long
>>> real_rate)
>>> -{
>>> -    int r = rate / 100, rr = real_rate / 100;
>>> -
>>> -    return (unsigned int)(abs(((rr - r) * 100) / r));
>>> -}
>>> -
>>>   int dispc_vp_set_clk_rate(struct dispc_device *dispc, u32
>>> hw_videoport,
>>>                 unsigned long rate)
>>>   {
>>> diff --git a/drivers/gpu/drm/tidss/tidss_dispc.h b/drivers/gpu/drm/
>>> tidss/tidss_dispc.h
>>> index 60c1b400eb89..42279312dcc1 100644
>>> --- a/drivers/gpu/drm/tidss/tidss_dispc.h
>>> +++ b/drivers/gpu/drm/tidss/tidss_dispc.h
>>> @@ -77,9 +77,6 @@ enum dispc_dss_subrevision {
>>>   };
>>>     struct dispc_features {
>>> -    int min_pclk_khz;
>>> -    int max_pclk_khz[DISPC_VP_MAX_BUS_TYPE];
>>> -
>>>       struct dispc_features_scaling scaling;
>>>         enum dispc_dss_subrevision subrev;
>>
> 

Hi Tomi,

On 11/12/25 15:21, Tomi Valkeinen wrote:
> Hi,
> 
> On 12/11/2025 11:43, Swamil Jain wrote:
>> Hi Tomi,
>>
>> On 11/12/25 15:10, Tomi Valkeinen wrote:
>>> Hi,
>>>
>>> On 04/11/2025 17:14, Swamil Jain wrote:
>>>> From: Jayesh Choudhary <j-choudhary@ti.com>
>>>>
>>>> The TIDSS hardware does not have independent maximum or minimum pixel
>>>> clock limits for each video port. Instead, these limits are determined
>>>> by the SoC's clock architecture. Previously, this constraint was
>>>> modeled using the 'max_pclk_khz' and 'min_pclk_khz' fields in
>>>> 'dispc_features', but this approach is static and does not account for
>>>> the dynamic behavior of PLLs.
>>>>
>>>> This patch removes the 'max_pclk_khz' and 'min_pclk_khz' fields from
>>>> 'dispc_features'. The correct way to check if a requested mode's pixel
>>>> clock is supported is by using 'clk_round_rate()' in the 'mode_valid()'
>>>> hook. If the best frequency match for the mode clock falls within the
>>>> supported tolerance, it is approved. TIDSS supports a 5% pixel clock
>>>> tolerance, which is now reflected in the validation logic.
>>>>
>>>> This change allows existing DSS-compatible drivers to be reused across
>>>> SoCs that only differ in their pixel clock characteristics. The
>>>> validation uses 'clk_round_rate()' for each mode, which may introduce
>>>> additional delay (about 3.5 ms for 30 modes), but this is generally
>>>> negligible. Users desiring faster validation may bypass these calls
>>>> selectively, for example, checking only the highest resolution mode,
>>>> as shown here[1].
>>>>
>>>> [1]: https://lore.kernel.org/all/20250704094851.182131-3-j-
>>>> choudhary@ti.com/
>>>>
>>>> Tested-by: Michael Walle <mwalle@kernel.org>
>>>> Reviewed-by: Devarsh Thakkar <devarsht@ti.com>
>>>> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
>>>> Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
>>>> Signed-off-by: Swamil Jain <s-jain1@ti.com>
>>>> ---
>>>>    drivers/gpu/drm/tidss/tidss_dispc.c | 86 +++++++++++------------------
>>>>    drivers/gpu/drm/tidss/tidss_dispc.h |  3 -
>>>>    2 files changed, 31 insertions(+), 58 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/
>>>> tidss/tidss_dispc.c
>>>> index d0b191c470ca..b11880178cba 100644
>>>> --- a/drivers/gpu/drm/tidss/tidss_dispc.c
>>>> +++ b/drivers/gpu/drm/tidss/tidss_dispc.c
>>>> @@ -57,12 +57,6 @@ static const u16
>>>> tidss_k2g_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
>>>>    };
>>>>      const struct dispc_features dispc_k2g_feats = {
>>>> -    .min_pclk_khz = 4375,
>>>> -
>>>> -    .max_pclk_khz = {
>>>> -        [DISPC_VP_DPI] = 150000,
>>>> -    },
>>>> -
>>>>        /*
>>>>         * XXX According TRM the RGB input buffer width up to 2560 should
>>>>         *     work on 3 taps, but in practice it only works up to 1280.
>>>> @@ -145,11 +139,6 @@ static const u16
>>>> tidss_am65x_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
>>>>    };
>>>>      const struct dispc_features dispc_am65x_feats = {
>>>> -    .max_pclk_khz = {
>>>> -        [DISPC_VP_DPI] = 165000,
>>>> -        [DISPC_VP_OLDI_AM65X] = 165000,
>>>> -    },
>>>> -
>>>>        .scaling = {
>>>>            .in_width_max_5tap_rgb = 1280,
>>>>            .in_width_max_3tap_rgb = 2560,
>>>> @@ -245,11 +234,6 @@ static const u16
>>>> tidss_j721e_common_regs[DISPC_COMMON_REG_TABLE_LEN] = {
>>>>    };
>>>>      const struct dispc_features dispc_j721e_feats = {
>>>> -    .max_pclk_khz = {
>>>> -        [DISPC_VP_DPI] = 170000,
>>>> -        [DISPC_VP_INTERNAL] = 600000,
>>>> -    },
>>>> -
>>>>        .scaling = {
>>>>            .in_width_max_5tap_rgb = 2048,
>>>>            .in_width_max_3tap_rgb = 4096,
>>>> @@ -316,11 +300,6 @@ const struct dispc_features dispc_j721e_feats = {
>>>>    };
>>>>      const struct dispc_features dispc_am625_feats = {
>>>> -    .max_pclk_khz = {
>>>> -        [DISPC_VP_DPI] = 165000,
>>>> -        [DISPC_VP_INTERNAL] = 170000,
>>>> -    },
>>>> -
>>>>        .scaling = {
>>>>            .in_width_max_5tap_rgb = 1280,
>>>>            .in_width_max_3tap_rgb = 2560,
>>>> @@ -377,15 +356,6 @@ const struct dispc_features dispc_am625_feats = {
>>>>    };
>>>>      const struct dispc_features dispc_am62a7_feats = {
>>>> -    /*
>>>> -     * if the code reaches dispc_mode_valid with VP1,
>>>> -     * it should return MODE_BAD.
>>>> -     */
>>>> -    .max_pclk_khz = {
>>>> -        [DISPC_VP_TIED_OFF] = 0,
>>>> -        [DISPC_VP_DPI] = 165000,
>>>> -    },
>>>> -
>>>>        .scaling = {
>>>>            .in_width_max_5tap_rgb = 1280,
>>>>            .in_width_max_3tap_rgb = 2560,
>>>> @@ -442,10 +412,6 @@ const struct dispc_features dispc_am62a7_feats = {
>>>>    };
>>>>      const struct dispc_features dispc_am62l_feats = {
>>>> -    .max_pclk_khz = {
>>>> -        [DISPC_VP_DPI] = 165000,
>>>> -    },
>>>> -
>>>>        .subrev = DISPC_AM62L,
>>>>          .common = "common",
>>>> @@ -1333,33 +1299,54 @@ static void dispc_vp_set_default_color(struct
>>>> dispc_device *dispc,
>>>>                DISPC_OVR_DEFAULT_COLOR2, (v >> 32) & 0xffff);
>>>>    }
>>>>    +/*
>>>> + * Calculate the percentage difference between the requested pixel
>>>> clock rate
>>>> + * and the effective rate resulting from calculating the clock
>>>> divider value.
>>>> + */
>>>> +unsigned int dispc_pclk_diff(unsigned long rate, unsigned long
>>>> real_rate)
>>>> +{
>>>> +    int r = rate / 100, rr = real_rate / 100;
>>>> +
>>>> +    return (unsigned int)(abs(((rr - r) * 100) / r));
>>>> +}
>>>> +
>>>> +static inline int check_pixel_clock(struct dispc_device *dispc,
>>>> +                 u32 hw_videoport, unsigned long clock)
>>>> +{
>>>
>>> Ah... Sorry, I was quite unclear in my comment to v7. I did not mean
>>> mark it as inline. I meant "move it inline", i.e. move this code into
>>> the dispc_vp_mode_valid function. This is just a few lines, and having
>>> it in a separate function makes it a bit more difficult to understand
>>> what are all the checks done in dispc_vp_mode_valid().
>>>
>>> I can do that change when applying the patches, if that's ok for you.
>>>
>>
>> Thanks Tomi, please do the required changes.
> 
> Actually, now that I was about to do the change, I realized the next
> patch adds an if check here. So maybe it's better to keep it as a
> separate function. I'll just drop the "inline".

Yeah, I think we can move it inline and accordingly modify the next 
patch also. But I think having a separate function makes it clear that 
we are skipping check for VPs with external clocking and we are having a 
similar check within the bridge driver. Please drop the "inline". Thanks 
for the re-work.

Regards,
Swamil

> 
>   Tomi
> 
>>
>> Regards,
>> Swamil
>>
>>>    Tomi
>>>
>>>> +    unsigned long round_clock;
>>>> +
>>>> +    round_clock = clk_round_rate(dispc->vp_clk[hw_videoport], clock);
>>>> +    /*
>>>> +     * To keep the check consistent with dispc_vp_set_clk_rate(), we
>>>> +     * use the same 5% check here.
>>>> +     */
>>>> +    if (dispc_pclk_diff(clock, round_clock) > 5)
>>>> +        return -EINVAL;
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>>    enum drm_mode_status dispc_vp_mode_valid(struct dispc_device *dispc,
>>>>                         u32 hw_videoport,
>>>>                         const struct drm_display_mode *mode)
>>>>    {
>>>>        u32 hsw, hfp, hbp, vsw, vfp, vbp;
>>>>        enum dispc_vp_bus_type bus_type;
>>>> -    int max_pclk;
>>>>          bus_type = dispc->feat->vp_bus_type[hw_videoport];
>>>>    -    max_pclk = dispc->feat->max_pclk_khz[bus_type];
>>>> -
>>>> -    if (WARN_ON(max_pclk == 0))
>>>> +    if (WARN_ON(bus_type == DISPC_VP_TIED_OFF))
>>>>            return MODE_BAD;
>>>>    -    if (mode->clock < dispc->feat->min_pclk_khz)
>>>> -        return MODE_CLOCK_LOW;
>>>> -
>>>> -    if (mode->clock > max_pclk)
>>>> -        return MODE_CLOCK_HIGH;
>>>> -
>>>>        if (mode->hdisplay > 4096)
>>>>            return MODE_BAD;
>>>>          if (mode->vdisplay > 4096)
>>>>            return MODE_BAD;
>>>>    +    if (check_pixel_clock(dispc, hw_videoport, mode->clock * 1000))
>>>> +        return MODE_CLOCK_RANGE;
>>>> +
>>>>        /* TODO: add interlace support */
>>>>        if (mode->flags & DRM_MODE_FLAG_INTERLACE)
>>>>            return MODE_NO_INTERLACE;
>>>> @@ -1423,17 +1410,6 @@ void dispc_vp_disable_clk(struct dispc_device
>>>> *dispc, u32 hw_videoport)
>>>>        clk_disable_unprepare(dispc->vp_clk[hw_videoport]);
>>>>    }
>>>>    -/*
>>>> - * Calculate the percentage difference between the requested pixel
>>>> clock rate
>>>> - * and the effective rate resulting from calculating the clock
>>>> divider value.
>>>> - */
>>>> -unsigned int dispc_pclk_diff(unsigned long rate, unsigned long
>>>> real_rate)
>>>> -{
>>>> -    int r = rate / 100, rr = real_rate / 100;
>>>> -
>>>> -    return (unsigned int)(abs(((rr - r) * 100) / r));
>>>> -}
>>>> -
>>>>    int dispc_vp_set_clk_rate(struct dispc_device *dispc, u32
>>>> hw_videoport,
>>>>                  unsigned long rate)
>>>>    {
>>>> diff --git a/drivers/gpu/drm/tidss/tidss_dispc.h b/drivers/gpu/drm/
>>>> tidss/tidss_dispc.h
>>>> index 60c1b400eb89..42279312dcc1 100644
>>>> --- a/drivers/gpu/drm/tidss/tidss_dispc.h
>>>> +++ b/drivers/gpu/drm/tidss/tidss_dispc.h
>>>> @@ -77,9 +77,6 @@ enum dispc_dss_subrevision {
>>>>    };
>>>>      struct dispc_features {
>>>> -    int min_pclk_khz;
>>>> -    int max_pclk_khz[DISPC_VP_MAX_BUS_TYPE];
>>>> -
>>>>        struct dispc_features_scaling scaling;
>>>>          enum dispc_dss_subrevision subrev;
>>>
>>
>