linux-kernel - [PATCH 2/3] drm/amd/display: Simplify get_dmif_switch_time

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Message-Id: <1ab1210048a4b485247cccba6721f1885c986331.1685342739.git.christophe.jaillet@wanadoo.fr>
Date:   Mon, 29 May 2023 09:18:55 +0200
From:   Christophe JAILLET <christophe.jaillet@...adoo.fr>
To:     Harry Wentland <harry.wentland@....com>,
        Leo Li <sunpeng.li@....com>,
        Rodrigo Siqueira <Rodrigo.Siqueira@....com>,
        Alex Deucher <alexander.deucher@....com>,
        Christian König <christian.koenig@....com>,
        "Pan, Xinhui" <Xinhui.Pan@....com>,
        David Airlie <airlied@...il.com>,
        Daniel Vetter <daniel@...ll.ch>
Cc:     linux-kernel@...r.kernel.org, kernel-janitors@...r.kernel.org,
        Christophe JAILLET <christophe.jaillet@...adoo.fr>,
        amd-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org
Subject: [PATCH 2/3] drm/amd/display: Simplify get_dmif_switch_time_us()

Thanks to the sanity check a few lines above:
    if (!h_total || !v_total || !pix_clk_khz)

and the computation done afterwards on these non 0 values, we know that
'pixels_per_second', 'pixels_per_frame' and 'refresh_rate' are not 0

The code can be simplified accordingly.

Signed-off-by: Christophe JAILLET <christophe.jaillet@...adoo.fr>
---
NOT compile tested. Because of some BROKEN in KConfig files.
---
 drivers/gpu/drm/amd/display/dc/dce/dce_mem_input.c | 13 -------------
 1 file changed, 13 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_mem_input.c b/drivers/gpu/drm/amd/display/dc/dce/dce_mem_input.c
index 091f0d68a045..eafe8561e55e 100644
--- a/drivers/gpu/drm/amd/display/dc/dce/dce_mem_input.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_mem_input.c
@@ -690,21 +690,8 @@ static uint32_t get_dmif_switch_time_us(
 	pixels_per_second = pix_clk_khz * 1000;
 	pixels_per_frame = h_total * v_total;
 
-	if (!pixels_per_second || !pixels_per_frame) {
-		/* avoid division by zero */
-		ASSERT(pixels_per_frame);
-		ASSERT(pixels_per_second);
-		return single_frame_time_multiplier * min_single_frame_time_us;
-	}
-
 	refresh_rate = pixels_per_second / pixels_per_frame;
 
-	if (!refresh_rate) {
-		/* avoid division by zero*/
-		ASSERT(refresh_rate);
-		return single_frame_time_multiplier * min_single_frame_time_us;
-	}
-
 	frame_time = us_in_sec / refresh_rate;
 
 	if (frame_time < min_single_frame_time_us)
-- 
2.34.1