| Message ID | 20231101-tidss-probe-v1-8-45149e0f9415@ideasonboard.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/tidss: Probe related fixes and cleanups | expand |
Hi Tomi, Thank you for the patch. On Wed, Nov 01, 2023 at 11:17:45AM +0200, Tomi Valkeinen wrote: > Add a helper function, dispc_is_idle(), which returns whether the DSS is > idle (i.e. is any video port enabled). > > For now we add a call to it in the suspend and resume callbacks, and > print a warning if in either place the DSS is not idle. Could you please explain here why these checks are needed/useful ? Why would the dispc not be idle ? > In the future > this can be used to detect if the bootloader had enabled the DSS, and > the driver can act on that. > > Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> > --- > drivers/gpu/drm/tidss/tidss_dispc.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/tidss/tidss_dispc.c > index 13db062892e3..a527c28c8833 100644 > --- a/drivers/gpu/drm/tidss/tidss_dispc.c > +++ b/drivers/gpu/drm/tidss/tidss_dispc.c > @@ -2603,10 +2603,18 @@ void dispc_vp_setup(struct dispc_device *dispc, u32 hw_videoport, > dispc_vp_set_color_mgmt(dispc, hw_videoport, state, newmodeset); > } > > +static bool dispc_is_idle(struct dispc_device *dispc) > +{ > + return REG_GET(dispc, DSS_SYSSTATUS, 9, 9); > +} > + > int dispc_runtime_suspend(struct dispc_device *dispc) > { > dev_dbg(dispc->dev, "suspend\n"); > > + if (!dispc_is_idle(dispc)) > + dev_warn(dispc->dev, "Bad HW state: DSS not idle when suspending"); > + > dispc->is_enabled = false; > > clk_disable_unprepare(dispc->fclk); > @@ -2620,6 +2628,9 @@ int dispc_runtime_resume(struct dispc_device *dispc) > > clk_prepare_enable(dispc->fclk); > > + if (!dispc_is_idle(dispc)) > + dev_warn(dispc->dev, "Bad HW state: DSS not idle when resuming"); > + > if (REG_GET(dispc, DSS_SYSSTATUS, 0, 0) == 0) > dev_warn(dispc->dev, "DSS FUNC RESET not done!\n"); >
On 01/11/2023 16:32, Laurent Pinchart wrote: > Hi Tomi, > > Thank you for the patch. > > On Wed, Nov 01, 2023 at 11:17:45AM +0200, Tomi Valkeinen wrote: >> Add a helper function, dispc_is_idle(), which returns whether the DSS is >> idle (i.e. is any video port enabled). >> >> For now we add a call to it in the suspend and resume callbacks, and >> print a warning if in either place the DSS is not idle. > > Could you please explain here why these checks are needed/useful ? Why > would the dispc not be idle ? I'll drop this. This was mostly a debugging aid for myself when testing runtime PM. Tomi
diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/tidss/tidss_dispc.c index 13db062892e3..a527c28c8833 100644 --- a/drivers/gpu/drm/tidss/tidss_dispc.c +++ b/drivers/gpu/drm/tidss/tidss_dispc.c @@ -2603,10 +2603,18 @@ void dispc_vp_setup(struct dispc_device *dispc, u32 hw_videoport, dispc_vp_set_color_mgmt(dispc, hw_videoport, state, newmodeset); } +static bool dispc_is_idle(struct dispc_device *dispc) +{ + return REG_GET(dispc, DSS_SYSSTATUS, 9, 9); +} + int dispc_runtime_suspend(struct dispc_device *dispc) { dev_dbg(dispc->dev, "suspend\n"); + if (!dispc_is_idle(dispc)) + dev_warn(dispc->dev, "Bad HW state: DSS not idle when suspending"); + dispc->is_enabled = false; clk_disable_unprepare(dispc->fclk); @@ -2620,6 +2628,9 @@ int dispc_runtime_resume(struct dispc_device *dispc) clk_prepare_enable(dispc->fclk); + if (!dispc_is_idle(dispc)) + dev_warn(dispc->dev, "Bad HW state: DSS not idle when resuming"); + if (REG_GET(dispc, DSS_SYSSTATUS, 0, 0) == 0) dev_warn(dispc->dev, "DSS FUNC RESET not done!\n");
Add a helper function, dispc_is_idle(), which returns whether the DSS is idle (i.e. is any video port enabled). For now we add a call to it in the suspend and resume callbacks, and print a warning if in either place the DSS is not idle. In the future this can be used to detect if the bootloader had enabled the DSS, and the driver can act on that. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> --- drivers/gpu/drm/tidss/tidss_dispc.c | 11 +++++++++++ 1 file changed, 11 insertions(+)