Hi Javier, On 01/30/2015 05:03 PM, Javier Martinez Canillas wrote: > Hello Joonyoung, > > On Fri, Jan 30, 2015 at 3:02 AM, Joonyoung Shim <jy0922.shim@xxxxxxxxxxx> wrote: >> +Cc Kukjin, >> >> Hi, >> >> On 01/29/2015 10:31 PM, Gustavo Padovan wrote: >>> From: Prathyush K <prathyush.k@xxxxxxxxxxx> >>> >>> When VPLL clock of less than 140 MHz was used and all the three >>> clocks - hdmiphy, hdmi, sclk_hdmi are disabled, the system hangs >>> during S2R when HDMI is connected. Since we want to use a vpll >>> clock of 70.5 MHz, we cannot disable these 3 clocks before suspending. >>> This patch moves the clk enable/disable of hdmi and sclk_hdmi >>> outside of the pm ops. Now system suspends and resumes with HDMI >>> connected with VPLL set at 70.5 MHz. >>> >>> Signed-off-by: Prathyush K <prathyush.k@xxxxxxxxxxx> >>> Signed-off-by: Andrew Bresticker <abrestic@xxxxxxxxxxxx> >>> Signed-off-by: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx> >>> >>> --- >>> This work depends on the HDMI support patches from Javier: >>> https://lkml.org/lkml/2015/1/20/235 >>> >>> This patch comes from a downstream tree (Google chormeOS) and it is >>> authored by a Samsung employee, but we still think this may not fix >>> the real cause of the bug, there might be something else that we >>> haven't found that could be the cause of this issue. Anyone has some >>> comment to add here? >> >> Hmm, do you test from which exynos SoC? >> > > I haven't the S2R case since it is broken in mainline for Exynos5420 > (even with $subject applied) but $subject fixes for me the system > crash we have discussed before [0]. That is when mixer_poweron() tries > to access the mixer register without hdmi_poweron() enabling the > "hdmi" clock. > >> Kukjin, if it is hw issue, do you know hw experts of exynos hdmi and >> could we get any advice? >> > > It would be great if someone can shed some light on both issues. > >>> --- >>> drivers/gpu/drm/exynos/exynos_hdmi.c | 17 +++++++++++------ >>> 1 file changed, 11 insertions(+), 6 deletions(-) >>> >>> diff --git a/drivers/gpu/drm/exynos/exynos_hdmi.c b/drivers/gpu/drm/exynos/exynos_hdmi.c >>> index 6aa0d65..7a473cb 100644 >>> --- a/drivers/gpu/drm/exynos/exynos_hdmi.c >>> +++ b/drivers/gpu/drm/exynos/exynos_hdmi.c >>> @@ -2064,9 +2064,6 @@ static void hdmi_poweron(struct exynos_drm_display *display) >>> regmap_update_bits(hdata->pmureg, PMU_HDMI_PHY_CONTROL, >>> PMU_HDMI_PHY_ENABLE_BIT, 1); >>> >>> - clk_prepare_enable(res->hdmi); >>> - clk_prepare_enable(res->sclk_hdmi); >>> - >>> hdmiphy_poweron(hdata); >>> hdmi_commit(display); >>> } >>> @@ -2088,9 +2085,6 @@ static void hdmi_poweroff(struct exynos_drm_display *display) >>> >>> cancel_delayed_work(&hdata->hotplug_work); >>> >>> - clk_disable_unprepare(res->sclk_hdmi); >>> - clk_disable_unprepare(res->hdmi); >>> - >>> /* reset pmu hdmiphy control bit to disable hdmiphy */ >>> regmap_update_bits(hdata->pmureg, PMU_HDMI_PHY_CONTROL, >>> PMU_HDMI_PHY_ENABLE_BIT, 0); >>> @@ -2254,6 +2248,14 @@ static int hdmi_resources_init(struct hdmi_context *hdata) >>> } else >>> res->reg_hdmi_en = NULL; >>> >>> + /* >>> + * These two clocks are not moved into hdmi_poweron/off since system >>> + * fails to suspend if VPLL clock of 70.5 MHz is used and these >>> + * clocks are disabled before suspend. So enable them here. >>> + */ >>> + clk_prepare_enable(res->sclk_hdmi); >>> + clk_prepare_enable(res->hdmi); >>> + >> >> Then twe clocks are turned on always. I don't think it's reasonable. >> > > Agreed that it would be better to gate/ungate the clocks as necessary > to reduce power consumption but OTOH is better to leave some clocks > enabled to avoid system crashes. Of course it would be even better to > understand the root cause and fix it. > It's ok to me if we apply workaround only about exynos5420 hdmi case. Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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