On 19/11/18 09:29, Andrzej Hajda wrote: > On 29.10.2018 12:46, Tomi Valkeinen wrote: >> 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 to bits to be set to the same value as DP0_SRCCTRL: > > s/to/two/ > > >> SSCG and BW27. All other bits can be zero. >> >> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx> >> --- >> 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)); > > > Wouldn't be better then to modify tc_srcctrl to support DP0 and DP1: > > tc_write(DP0_SRCCTRL, tc_srcctrl(tc, 0)); > > tc_write(DP1_SRCCTRL, tc_srcctrl(tc, 1)); In a normal case I would agree. But on this IC, there's only a single DisplayPort output, DP0. However, for some reason, DP1_SRCCTRL also needs to be configured (and the register is not even in the docs) for DP0 to work. Possibly there are IC versions with two DP ports, but I don't know how DP1_SRCCTRL needs to be configured on those. So I'd rather keep the normal configuration (for DP0 with tc_srcctrl) separate from setting these magical bits in DP1_SRCCTRL needed to make the IC work. Tomi -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
