[Intel-gfx] [PATCH 6/7] drm/i915/skl: Update watermarks for Y tiling

[Tvrtko Ursulin]

On 02/24/2015 07:26 PM, Damien Lespiau wrote:
> On Mon, Feb 23, 2015 at 03:56:00PM +0000, Tvrtko Ursulin wrote:
>> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>
>> Display watermarks need different programming for different tiling
>> modes.
>>
>> Set the relevant flag so this happens during the plane commit and
>> add relevant data into a structure made available to the watermark
>> computation code.
>>
>> v2: Pass in tiling info to sprite plane updates as well.
>> v3: Rebased for plane handling changes.
>> v4: Handle fb == NULL when plane is disabled.
>> v5: Refactored for addfb2 interface.
>> v6: Refactored for fb modifier changes.
>> v7: Updated for atomic commit by only updating watermarks when tiling changes.
>>
>> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>> Acked-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira at intel.com>
>> Acked-by: Matt Roper <matthew.d.roper at intel.com>
>> ---
>>   drivers/gpu/drm/i915/intel_display.c |  6 ++++++
>>   drivers/gpu/drm/i915/intel_drv.h     |  1 +
>>   drivers/gpu/drm/i915/intel_pm.c      | 33 ++++++++++++++++++++++++++++-----
>>   drivers/gpu/drm/i915/intel_sprite.c  |  6 ++++++
>>   4 files changed, 41 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
>> index c622b11..74d4923 100644
>> --- a/drivers/gpu/drm/i915/intel_display.c
>> +++ b/drivers/gpu/drm/i915/intel_display.c
>> @@ -11985,6 +11985,12 @@ intel_check_primary_plane(struct drm_plane *plane,
>>   			INTEL_FRONTBUFFER_PRIMARY(intel_crtc->pipe);
>>
>>   		intel_crtc->atomic.update_fbc = true;
>> +
>> +		/* Update watermarks on tiling changes. */
>> +		if (!plane->state->fb || !state->base.fb ||
>> +		    plane->state->fb->modifier[0] !=
>> +		    state->base.fb->modifier[0])
>> +			intel_crtc->atomic.update_wm = true;
>>   	}
>>
>>   	return 0;
>> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
>> index 399d2b2..b124548 100644
>> --- a/drivers/gpu/drm/i915/intel_drv.h
>> +++ b/drivers/gpu/drm/i915/intel_drv.h
>> @@ -501,6 +501,7 @@ struct intel_plane_wm_parameters {
>>   	uint8_t bytes_per_pixel;
>>   	bool enabled;
>>   	bool scaled;
>> +	u64 tiling;
>>   };
>>
>>   struct intel_plane {
>> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
>> index f7c9938..006e635 100644
>> --- a/drivers/gpu/drm/i915/intel_pm.c
>> +++ b/drivers/gpu/drm/i915/intel_pm.c
>> @@ -2662,6 +2662,7 @@ static void skl_compute_wm_pipe_parameters(struct drm_crtc *crtc,
>>   	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
>>   	enum pipe pipe = intel_crtc->pipe;
>>   	struct drm_plane *plane;
>> +	struct drm_framebuffer *fb;
>>   	int i = 1; /* Index for sprite planes start */
>>
>>   	p->active = intel_crtc_active(crtc);
>> @@ -2677,6 +2678,14 @@ static void skl_compute_wm_pipe_parameters(struct drm_crtc *crtc,
>>   			crtc->primary->fb->bits_per_pixel / 8;
>>   		p->plane[0].horiz_pixels = intel_crtc->config->pipe_src_w;
>>   		p->plane[0].vert_pixels = intel_crtc->config->pipe_src_h;
>> +		p->plane[0].tiling = DRM_FORMAT_MOD_NONE;
>> +		fb = crtc->primary->fb;
>> +		/*
>> +		 * Framebuffer can be NULL on plane disable, but it does not
>> +		 * matter for watermarks if we assume no tiling in that case.
>> +		 */
>> +		if (fb)
>> +			p->plane[0].tiling = fb->modifier[0];
>>
>>   		p->cursor.enabled = true;
>>   		p->cursor.bytes_per_pixel = 4;
>> @@ -2702,6 +2711,7 @@ static bool skl_compute_plane_wm(struct skl_pipe_wm_parameters *p,
>>   {
>>   	uint32_t method1, method2, plane_bytes_per_line, res_blocks, res_lines;
>>   	uint32_t result_bytes;
>> +	uint32_t y_tile_minimum;
>>
>>   	if (mem_value == 0 || !p->active || !p_params->enabled)
>>   		return false;
>> @@ -2718,11 +2728,16 @@ static bool skl_compute_plane_wm(struct skl_pipe_wm_parameters *p,
>>   	plane_bytes_per_line = p_params->horiz_pixels *
>>   					p_params->bytes_per_pixel;
>>
>> -	/* For now xtile and linear */
>> -	if (((ddb_allocation * 512) / plane_bytes_per_line) >= 1)
>> -		result_bytes = min(method1, method2);
>> -	else
>> -		result_bytes = method1;
>> +	if (p_params->tiling == I915_FORMAT_MOD_Y_TILED ||
>> +	    p_params->tiling == I915_FORMAT_MOD_Yf_TILED) {
>> +		y_tile_minimum = plane_bytes_per_line * 4;
>> +		result_bytes = max(method2, y_tile_minimum);
>> +	} else {
>> +		if (((ddb_allocation * 512) / plane_bytes_per_line) >= 1)
>> +			result_bytes = min(method1, method2);
>> +		else
>> +			result_bytes = method1;
>> +	}
>
> While this was what was documented at some point, it's not anymore.
> Would need an extra patch before this one to introduce
> plane_blocks_per_line and then this one on top.

Don't follow - what is plane_blocks_per_line and where and how would you 
add it before this patch?

Regards,

Tvrtko