| Message ID | 1557500600-19771-1-git-send-email-yannick.fertre@st.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/stm: ltdc: remove clk_round_rate comment | expand |
Dear Yannick, Thank you for your patch, In your patch, you have removed clk_disable() & clk_enable(). Could you please double confirm ? thanks Philippe :-) On 5/10/19 5:03 PM, Yannick Fertré wrote: > Clk_round_rate returns rounded clock without changing > the hardware in any way. > This function couldn't replace set_rate/get_rate calls. > Todo comment has been removed & a new log inserted. > > Signed-off-by: Yannick Fertré <yannick.fertre@st.com> > --- > drivers/gpu/drm/stm/ltdc.c | 10 +++------- > 1 file changed, 3 insertions(+), 7 deletions(-) > > diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c > index 97912e2..2f8aa2e 100644 > --- a/drivers/gpu/drm/stm/ltdc.c > +++ b/drivers/gpu/drm/stm/ltdc.c > @@ -507,20 +507,16 @@ static bool ltdc_crtc_mode_fixup(struct drm_crtc *crtc, > struct ltdc_device *ldev = crtc_to_ltdc(crtc); > int rate = mode->clock * 1000; > > - /* > - * TODO clk_round_rate() does not work yet. When ready, it can > - * be used instead of clk_set_rate() then clk_get_rate(). > - */ > - > - clk_disable(ldev->pixel_clk); > if (clk_set_rate(ldev->pixel_clk, rate) < 0) { > DRM_ERROR("Cannot set rate (%dHz) for pixel clk\n", rate); > return false; > } > - clk_enable(ldev->pixel_clk); > > adjusted_mode->clock = clk_get_rate(ldev->pixel_clk) / 1000; > > + DRM_DEBUG_DRIVER("requested clock %dkHz, adjusted clock %dkHz\n", > + mode->clock, adjusted_mode->clock); > + > return true; > } > >
Dear Philippe, you're right, clk_disable() & clk_enable() are necessary with STM32F4 SOC (not for STM32MP1). I'll revert this part of the patch. Many thanks
diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c index 97912e2..2f8aa2e 100644 --- a/drivers/gpu/drm/stm/ltdc.c +++ b/drivers/gpu/drm/stm/ltdc.c @@ -507,20 +507,16 @@ static bool ltdc_crtc_mode_fixup(struct drm_crtc *crtc, struct ltdc_device *ldev = crtc_to_ltdc(crtc); int rate = mode->clock * 1000; - /* - * TODO clk_round_rate() does not work yet. When ready, it can - * be used instead of clk_set_rate() then clk_get_rate(). - */ - - clk_disable(ldev->pixel_clk); if (clk_set_rate(ldev->pixel_clk, rate) < 0) { DRM_ERROR("Cannot set rate (%dHz) for pixel clk\n", rate); return false; } - clk_enable(ldev->pixel_clk); adjusted_mode->clock = clk_get_rate(ldev->pixel_clk) / 1000; + DRM_DEBUG_DRIVER("requested clock %dkHz, adjusted clock %dkHz\n", + mode->clock, adjusted_mode->clock); + return true; }
Clk_round_rate returns rounded clock without changing the hardware in any way. This function couldn't replace set_rate/get_rate calls. Todo comment has been removed & a new log inserted. Signed-off-by: Yannick Fertré <yannick.fertre@st.com> --- drivers/gpu/drm/stm/ltdc.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-)