So now that this is working (at least on a single device), I figured it was a good time to send out an RFC to start discussion about how to do this properly, in particular the CCF/powerdomain parts. The first patch adds flags so we can mark power domains and leaf node clocks which might (or might not) be enabled by bootloader and which we want to inherit when real display driver is probed. (There might be use-cases outside of display.. such as debug serial port? I guess display is the most common/complex/useful use-case.) From the CCF/genpd standpoint, "inherit" really just means "fixup enable/ prepare_count and don't automatically switch off in lateinit". The rest of the complexity is in the display driver. For display, there are two different cases depending on whether the display driver is built as a module (ie. probes after lateinit) or not. If the display driver is built as a module, then we want efifb to keep working after the clk_disable_unused + genpd_power_off_unused late_initcall's. And in either case, we want the display driver to be able to detect that display is already on (by checking whether various clocks are already enabled) so that it knows to readback the hw state. (And not try to do things like clk_set_rate() on already running clocks.) Right now this is working on 8x16 (dragonboard 410c). I'm not sure if we'll hit more issues in CCF with more complex devices due to separate GCC and MMCC clock controllers (a bit fuzzy on how things work with initially unparented clocks, if for example MMCC probes before it's GCC parent clocks.. and in general I am by no means an expert about the common clock framework). Certainly I'd like to hear suggestions about how to procede on the CCF/genpd front. I am aware of another similar RFC[1]. Although on most of the snapdragon devices you can in theory enable/disable the bootloader splashscreen via a 'fastboot oem select-display-panel' command, so I think whatever solution we have needs to introspect the hw to decide what to do. The latest version of these patches (plus various cleanups/etc that they depend on) can be found here[2] [1] https://lkml.org/lkml/2017/6/28/188 [2] https://github.com/freedreno/kernel-msm/commits/display-handover Rob Clark (3): clk: inherit display clocks enabled by bootloader drm/msm: inherit display from bootloader drm/bridge: adv7511: deal with bootloader lighting up display drivers/clk/clk.c | 18 ++++ drivers/clk/qcom/common.c | 28 +++++ drivers/clk/qcom/gcc-msm8916.c | 15 +-- drivers/clk/qcom/gdsc.c | 6 ++ drivers/clk/qcom/gdsc.h | 1 + drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 57 ++++++---- drivers/gpu/drm/bridge/adv7511/adv7533.c | 3 + drivers/gpu/drm/msm/dsi/dsi.h | 1 + drivers/gpu/drm/msm/dsi/dsi_host.c | 32 ++++++ drivers/gpu/drm/msm/dsi/phy/dsi_phy.c | 5 +- drivers/gpu/drm/msm/dsi/phy/dsi_phy.h | 1 + drivers/gpu/drm/msm/dsi/pll/dsi_pll_14nm.c | 2 + drivers/gpu/drm/msm/dsi/pll/dsi_pll_28nm.c | 2 + drivers/gpu/drm/msm/dsi/pll/dsi_pll_28nm_8960.c | 2 + drivers/gpu/drm/msm/mdp/mdp5/mdp5_cmd_encoder.c | 8 ++ drivers/gpu/drm/msm/mdp/mdp5/mdp5_crtc.c | 21 ++++ drivers/gpu/drm/msm/mdp/mdp5/mdp5_ctl.c | 48 +++++++++ drivers/gpu/drm/msm/mdp/mdp5/mdp5_ctl.h | 3 + drivers/gpu/drm/msm/mdp/mdp5/mdp5_encoder.c | 132 ++++++++++++++++++++++-- drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c | 79 +++++++++++++- drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h | 11 ++ drivers/gpu/drm/msm/mdp/mdp5/mdp5_plane.c | 79 ++++++++++++++ drivers/gpu/drm/msm/mdp/mdp5/mdp5_smp.c | 45 ++++++++ drivers/gpu/drm/msm/mdp/mdp5/mdp5_smp.h | 2 + drivers/gpu/drm/msm/msm_drv.c | 3 + drivers/gpu/drm/msm/msm_drv.h | 2 + drivers/gpu/drm/msm/msm_fbdev.c | 15 ++- drivers/gpu/drm/msm/msm_kms.h | 2 + include/linux/clk-provider.h | 1 + include/linux/clk.h | 9 ++ 30 files changed, 591 insertions(+), 42 deletions(-) -- 2.13.0 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
