4.20-stable review patch. If anyone has any objections, please let me know.
------------------
[ Upstream commit 9a63bd6fe1b5590ffa42ae2ed22ee21363293e31 ]
Initially DP0_SRCCTRL is set to a static value which includes DP0_SRCCTRL_LANES_2 and DP0_SRCCTRL_BW27, even when only 1 lane of 1.62Gbps speed is used. DP1_SRCCTRL is configured to a magic number.
This patch changes the configuration as follows:
Configure DP0_SRCCTRL by using tc_srcctrl() which provides the correct value.
DP1_SRCCTRL needs two bits to be set to the same value as DP0_SRCCTRL: SSCG and BW27. All other bits can be zero.
Signed-off-by: Tomi Valkeinen tomi.valkeinen@ti.com Reviewed-by: Andrzej Hajda a.hajda@samsung.com Signed-off-by: Andrzej Hajda a.hajda@samsung.com Link: https://patchwork.freedesktop.org/patch/msgid/20190103115954.12785-5-tomi.va... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/bridge/tc358767.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c index fee53422c31f..ab299f4debfa 100644 --- a/drivers/gpu/drm/bridge/tc358767.c +++ b/drivers/gpu/drm/bridge/tc358767.c @@ -836,12 +836,11 @@ static int tc_main_link_setup(struct tc_data *tc) if (!tc->mode) return -EINVAL;
- /* from excel file - DP0_SrcCtrl */ - tc_write(DP0_SRCCTRL, DP0_SRCCTRL_SCRMBLDIS | DP0_SRCCTRL_EN810B | - DP0_SRCCTRL_LANESKEW | DP0_SRCCTRL_LANES_2 | - DP0_SRCCTRL_BW27 | DP0_SRCCTRL_AUTOCORRECT); - /* from excel file - DP1_SrcCtrl */ - tc_write(DP1_SRCCTRL, 0x00003083); + tc_write(DP0_SRCCTRL, tc_srcctrl(tc)); + /* SSCG and BW27 on DP1 must be set to the same as on DP0 */ + tc_write(DP1_SRCCTRL, + (tc->link.spread ? DP0_SRCCTRL_SSCG : 0) | + ((tc->link.base.rate != 162000) ? DP0_SRCCTRL_BW27 : 0));
rate = clk_get_rate(tc->refclk); switch (rate) {