Messages in this thread | | | Date | Tue, 7 Feb 2023 17:25:37 +0200 | Subject | Re: [PATCH v12 13/14] drm/msm/disp/dpu: add PSR support for eDP interface in dpu driver | From | Dmitry Baryshkov <> |
| |
On 07/02/2023 16:26, Vinod Polimera wrote: > > >> -----Original Message----- >> From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> >> Sent: Tuesday, January 31, 2023 6:29 PM >> To: Vinod Polimera (QUIC) <quic_vpolimer@quicinc.com>; dri- >> devel@lists.freedesktop.org; linux-arm-msm@vger.kernel.org; >> freedreno@lists.freedesktop.org; devicetree@vger.kernel.org >> Cc: linux-kernel@vger.kernel.org; robdclark@gmail.com; >> dianders@chromium.org; swboyd@chromium.org; Kalyan Thota (QUIC) >> <quic_kalyant@quicinc.com>; Kuogee Hsieh (QUIC) >> <quic_khsieh@quicinc.com>; Vishnuvardhan Prodduturi (QUIC) >> <quic_vproddut@quicinc.com>; Bjorn Andersson (QUIC) >> <quic_bjorande@quicinc.com>; Abhinav Kumar (QUIC) >> <quic_abhinavk@quicinc.com>; Sankeerth Billakanti (QUIC) >> <quic_sbillaka@quicinc.com> >> Subject: Re: [PATCH v12 13/14] drm/msm/disp/dpu: add PSR support for eDP >> interface in dpu driver >> >> >> On 30/01/2023 17:11, Vinod Polimera wrote: >>> Enable PSR on eDP interface using drm self-refresh librabry. >>> This patch uses a trigger from self-refresh library to enter/exit >>> into PSR, when there are no updates from framework. >>> >>> Signed-off-by: Kalyan Thota <quic_kalyant@quicinc.com> >>> Signed-off-by: Vinod Polimera <quic_vpolimer@quicinc.com> >>> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> >>> --- >>> drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 13 ++++++++++++- >>> drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 14 ++++++++++++++ >>> drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 2 +- >>> 3 files changed, 27 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c >> b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c >>> index f29a339..60e5984 100644 >>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c >>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c >>> @@ -21,6 +21,7 @@ >>> #include <drm/drm_probe_helper.h> >>> #include <drm/drm_rect.h> >>> #include <drm/drm_vblank.h> >>> +#include <drm/drm_self_refresh_helper.h> >>> >>> #include "dpu_kms.h" >>> #include "dpu_hw_lm.h" >>> @@ -1021,6 +1022,9 @@ static void dpu_crtc_disable(struct drm_crtc *crtc, >>> >>> DRM_DEBUG_KMS("crtc%d\n", crtc->base.id); >>> >>> + if (old_crtc_state->self_refresh_active) >>> + return; >>> + >> >> I have been looking at the crtc_needs_disable(). It explicitly mentions >> that 'We also need to run through the crtc_funcs->disable() function >> [..] if it's transitioning to self refresh mode...'. Don't we need to >> perform some cleanup here (like disabling the vblank irq handling, >> freeing the bandwidth, etc)? > > When self refresh active is enabled, then we will clean up irq handling and bandwidth etc. > The above case is to handle display off commit triggered when we are in psr as all > the resources are already cleaned up . we just need to do an early return. >> >>> /* Disable/save vblank irq handling */ >>> drm_crtc_vblank_off(crtc); >>> >>> @@ -1577,7 +1581,7 @@ struct drm_crtc *dpu_crtc_init(struct drm_device >> *dev, struct drm_plane *plane, >>> { >>> struct drm_crtc *crtc = NULL; >>> struct dpu_crtc *dpu_crtc = NULL; >>> - int i; >>> + int i, ret; >>> >>> dpu_crtc = kzalloc(sizeof(*dpu_crtc), GFP_KERNEL); >>> if (!dpu_crtc) >>> @@ -1614,6 +1618,13 @@ struct drm_crtc *dpu_crtc_init(struct >> drm_device *dev, struct drm_plane *plane, >>> /* initialize event handling */ >>> spin_lock_init(&dpu_crtc->event_lock); >>> >>> + ret = drm_self_refresh_helper_init(crtc); >>> + if (ret) { >>> + DPU_ERROR("Failed to initialize %s with self-refresh helpers %d\n", >>> + crtc->name, ret); >>> + return ERR_PTR(ret); >>> + } >>> + >>> DRM_DEBUG_KMS("%s: successfully initialized crtc\n", dpu_crtc- >>> name); >>> return crtc; >>> } >>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c >> b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c >>> index 01b7509..450abb1 100644 >>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c >>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c >>> @@ -12,6 +12,7 @@ >>> #include <linux/kthread.h> >>> #include <linux/seq_file.h> >>> >>> +#include <drm/drm_atomic.h> >>> #include <drm/drm_crtc.h> >>> #include <drm/drm_file.h> >>> #include <drm/drm_probe_helper.h> >>> @@ -1212,11 +1213,24 @@ static void >> dpu_encoder_virt_atomic_disable(struct drm_encoder *drm_enc, >>> struct drm_atomic_state *state) >>> { >>> struct dpu_encoder_virt *dpu_enc = NULL; >>> + struct drm_crtc *crtc; >>> + struct drm_crtc_state *old_state = NULL; >>> int i = 0; >>> >>> dpu_enc = to_dpu_encoder_virt(drm_enc); >>> DPU_DEBUG_ENC(dpu_enc, "\n"); >>> >>> + crtc = drm_atomic_get_old_crtc_for_encoder(state, drm_enc); >>> + if (crtc) >>> + old_state = drm_atomic_get_old_crtc_state(state, crtc); >>> + >>> + /* >>> + * The encoder is already disabled if self refresh mode was set earlier, >>> + * in the old_state for the corresponding crtc. >>> + */ >>> + if (old_state && old_state->self_refresh_active) >>> + return; >>> + >> >> Again the same question here, doesn't crtc_needs_disable() take care of >> this clause? I might be missing something in the PSR state transitions. >> Could you please add some explanation here? > Same usecase as above, applies to encoder disable also when triggered via disable commit > When driver is in psr state.
Ack, thank you for the explanations. I'd like to take another glance later today, but generally it look good to me.
-- With best wishes Dmitry
| |