Re: [v2,03/10] drm/sun4i: Protect the TCON pixel clocks

From: Giulio Benetti
Date: Fri Feb 23 2018 - 09:05:36 EST


From: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>

Both TCON clocks are very sensitive to clock changes, since any change
might lead to improper timings.

Make sure our rate is never changed.

Tested-by: Giulio Benetti <giulio.benetti@xxxxxxxxxxxxxxxx>
Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/sun4i/sun4i_tcon.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index b73acab74867..cbe87cee13d1 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -261,7 +261,7 @@ static void sun4i_tcon0_mode_set_common(struct sun4i_tcon *tcon,
const struct drm_display_mode *mode)
{
/* Configure the dot clock */
- clk_set_rate(tcon->dclk, mode->crtc_clock * 1000);
+ clk_set_rate_exclusive(tcon->dclk, mode->crtc_clock * 1000);

/* Set the resolution */
regmap_write(tcon->regs, SUN4I_TCON0_BASIC0_REG,
@@ -419,7 +419,7 @@ static void sun4i_tcon1_mode_set(struct sun4i_tcon *tcon,
WARN_ON(!tcon->quirks->has_channel_1);

/* Configure the dot clock */
- clk_set_rate(tcon->sclk1, mode->crtc_clock * 1000);
+ clk_set_rate_exclusive(tcon->sclk1, mode->crtc_clock * 1000);

/* Adjust clock delay */
clk_delay = sun4i_tcon_get_clk_delay(mode, 1);