Merge drm/drm-next into drm-misc-next

Backmerging from drm/drm-next for v5.16-rc1.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

1 files changed, 12 insertions, 14 deletions

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
index b28ea5d6a3e2..3e8d9e2d1b67 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
@@ -1176,26 +1176,24 @@ static bool vop_crtc_mode_fixup(struct drm_crtc *crtc,
 	 *
 	 * Action plan:
 	 *
-	 * 1. When DRM gives us a mode, we should add 999 Hz to it.  That way
-	 *    if the clock we need is 60000001 Hz (~60 MHz) and DRM tells us to
-	 *    make 60000 kHz then the clock framework will actually give us
-	 *    the right clock.
+	 * 1. Try to set the exact rate first, and confirm the clock framework
+	 *    can provide it.
 	 *
-	 *    NOTE: if the PLL (maybe through a divider) could actually make
-	 *    a clock rate 999 Hz higher instead of the one we want then this
-	 *    could be a problem.  Unfortunately there's not much we can do
-	 *    since it's baked into DRM to use kHz.  It shouldn't matter in
-	 *    practice since Rockchip PLLs are controlled by tables and
-	 *    even if there is a divider in the middle I wouldn't expect PLL
-	 *    rates in the table that are just a few kHz different.
+	 * 2. If the clock framework cannot provide the exact rate, we should
+	 *    add 999 Hz to the requested rate.  That way if the clock we need
+	 *    is 60000001 Hz (~60 MHz) and DRM tells us to make 60000 kHz then
+	 *    the clock framework will actually give us the right clock.
 	 *
-	 * 2. Get the clock framework to round the rate for us to tell us
+	 * 3. Get the clock framework to round the rate for us to tell us
 	 *    what it will actually make.
 	 *
-	 * 3. Store the rounded up rate so that we don't need to worry about
+	 * 4. Store the rounded up rate so that we don't need to worry about
 	 *    this in the actual clk_set_rate().
 	 */
-	rate = clk_round_rate(vop->dclk, adjusted_mode->clock * 1000 + 999);
+	rate = clk_round_rate(vop->dclk, adjusted_mode->clock * 1000);
+	if (rate / 1000 != adjusted_mode->clock)
+		rate = clk_round_rate(vop->dclk,
+				      adjusted_mode->clock * 1000 + 999);
 	adjusted_mode->clock = DIV_ROUND_UP(rate, 1000);
 
 	return true;