The only information in the datasheet regarding this divider is a note
in SYS_PLLPARAM register documentation which states that when LSCLK is
270 MHz, LSCLK_DIV should be 1. What should LSCLK_DIV be set to when
LSCLK is 162 MHz (for DP 1.62G mode) is unclear, but empirical test
confirms using LSCLK_DIV 1 has no adverse effects either. In the worst
case, the internal TC358767 clock would run faster.

Reviewed-by: Alexander Stein <[email protected]>
Signed-off-by: Marek Vasut <[email protected]>
---
Cc: Andrzej Hajda <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: David Airlie <[email protected]>
Cc: Jernej Skrabec <[email protected]>
Cc: Jonas Karlman <[email protected]>
Cc: Laurent Pinchart <[email protected]>
Cc: Lucas Stach <[email protected]>
Cc: Maarten Lankhorst <[email protected]>
Cc: Maxime Ripard <[email protected]>
Cc: Neil Armstrong <[email protected]>
Cc: Robert Foss <[email protected]>
Cc: Thomas Zimmermann <[email protected]>
Cc: [email protected]
Cc: [email protected]
---
V2: No change
V3: No change
V4: - Add RB from Alexander
---
 drivers/gpu/drm/bridge/tc358767.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/tc358767.c 
b/drivers/gpu/drm/bridge/tc358767.c
index 19684b8400bef..0c6912bd5ec9e 100644
--- a/drivers/gpu/drm/bridge/tc358767.c
+++ b/drivers/gpu/drm/bridge/tc358767.c
@@ -738,7 +738,7 @@ static int tc_stream_clock_calc(struct tc_data *tc)
 static int tc_set_syspllparam(struct tc_data *tc)
 {
        unsigned long rate;
-       u32 pllparam = SYSCLK_SEL_LSCLK | LSCLK_DIV_2;
+       u32 pllparam = SYSCLK_SEL_LSCLK | LSCLK_DIV_1;
 
        rate = clk_get_rate(tc->refclk);
        switch (rate) {
-- 
2.43.0

Reply via email to