[PATCH 3/4] drm/amd/display: In VRR mode, do DRM core vblank handling at end of vblank.

Mario Kleiner mario.kleiner.de at gmail.com
Thu Mar 21 09:39:13 UTC 2019


On Wed, Mar 20, 2019 at 1:53 PM Kazlauskas, Nicholas
<Nicholas.Kazlauskas at amd.com> wrote:
>
> On 3/20/19 3:51 AM, Mario Kleiner wrote:
> > Ok, fixed all the style issues and ran checkpatch over the patches. Thanks.
> >
> > On Tue, Mar 19, 2019 at 2:32 PM Kazlauskas, Nicholas
> > <Nicholas.Kazlauskas at amd.com> wrote:
> >>
> >> On 3/19/19 9:23 AM, Kazlauskas, Nicholas wrote:
> >>> On 3/18/19 1:19 PM, Mario Kleiner wrote:
> >>>> In VRR mode, proper vblank/pageflip timestamps can only be computed
> >>>> after the display scanout position has left front-porch. Therefore
> >>>> delay calls to drm_crtc_handle_vblank(), and thereby calls to
> >>>> drm_update_vblank_count() and pageflip event delivery, to after the
> >>>> end of front-porch when in VRR mode.
> >>>>
> >>>> We add a new vupdate irq, which triggers at the end of the vupdate
> >>>> interval, ie. at the end of vblank, and calls the core vblank handler
> >>>> function. The new irq handler is not executed in standard non-VRR
> >>>> mode, so vblank handling for fixed refresh rate mode is identical
> >>>> to the past implementation.
> >>>>
> >>>> Signed-off-by: Mario Kleiner <mario.kleiner.de at gmail.com>
> >>
> >> Looks I lost some of my comments I wanted to send in my last email. Just
> >> a few nitpicks (including some things Paul mentioned).
> >>
> >> Also meant to CC Harry on this as well.
> >>
> >>>> ---
> >>>>     drivers/gpu/drm/amd/amdgpu/amdgpu.h                |   1 +
> >>>>     drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c  | 129 ++++++++++++++++++++-
> >>>>     drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h  |   9 ++
> >>>>     .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c  |  22 ++++
> >>>>     .../amd/display/dc/irq/dce110/irq_service_dce110.c |   7 +-
> >>>>     .../amd/display/dc/irq/dce120/irq_service_dce120.c |   7 +-
> >>>>     .../amd/display/dc/irq/dce80/irq_service_dce80.c   |   6 +-
> >>>>     .../amd/display/dc/irq/dcn10/irq_service_dcn10.c   |  40 +++++--
> >>>>     8 files changed, 205 insertions(+), 16 deletions(-)
> >>>>
> >>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> >>>> index f88761a..64167dd 100644
> >>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> >>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> >>>> @@ -827,6 +827,7 @@ struct amdgpu_device {
> >>>>       /* For pre-DCE11. DCE11 and later are in "struct amdgpu_device->dm" */
> >>>>       struct work_struct              hotplug_work;
> >>>>       struct amdgpu_irq_src           crtc_irq;
> >>>> +    struct amdgpu_irq_src           vupdate_irq;
> >>>>       struct amdgpu_irq_src           pageflip_irq;
> >>>>       struct amdgpu_irq_src           hpd_irq;
> >>>>
> >>>> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> >>>> index 85e4f87..555d9e9f 100644
> >>>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> >>>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> >>>> @@ -315,6 +315,32 @@ static void dm_pflip_high_irq(void *interrupt_params)
> >>>>       drm_crtc_vblank_put(&amdgpu_crtc->base);
> >>>>     }
> >>>>
> >>>> +static void dm_vupdate_high_irq(void *interrupt_params)
> >>>> +{
> >>>> +    struct common_irq_params *irq_params = interrupt_params;
> >>>> +    struct amdgpu_device *adev = irq_params->adev;
> >>>> +    struct amdgpu_crtc *acrtc;
> >>>> +    struct dm_crtc_state *acrtc_state;
> >>>> +
> >>>> +    acrtc = get_crtc_by_otg_inst(adev, irq_params->irq_src - IRQ_TYPE_VUPDATE);
> >>>> +
> >>>> +    if (acrtc) {
> >>>> +            acrtc_state = to_dm_crtc_state(acrtc->base.state);
> >>>> +
> >>>> +            DRM_DEBUG_DRIVER("crtc:%d, vupdate-vrr:%d\n", acrtc->crtc_id,
> >>>> +                             amdgpu_dm_vrr_active(acrtc_state));
> >>>> +
> >>>> +            /* Core vblank handling is done here after end of front-porch in
> >>>> +             * vrr mode, as vblank timestamping will give valid results
> >>>> +             * while now done after front-porch. This will also deliver
> >>>> +             * page-flip completion events that have been queued to us
> >>>> +             * if a pageflip happened inside front-porch.
> >>>> +             */
> >>>> +            if (amdgpu_dm_vrr_active(acrtc_state))
> >>>> +                    drm_crtc_handle_vblank(&acrtc->base)
> >>> I was thinking that 3 and 4 might have to be merged, but VRR pflip
> >>> timestamping seems to be the same as it was before (off by a line or
> >>> two) since it's not handled here yet. This seems to fix vblank events
> >>> and timestamping at least.
> >>>
> >>>> +    }
> >>>> +}
> >>>> +
> >>>>     static void dm_crtc_high_irq(void *interrupt_params)
> >>>>     {
> >>>>       struct common_irq_params *irq_params = interrupt_params;
> >>>> @@ -325,11 +351,24 @@ static void dm_crtc_high_irq(void *interrupt_params)
> >>>>       acrtc = get_crtc_by_otg_inst(adev, irq_params->irq_src - IRQ_TYPE_VBLANK);
> >>>>
> >>>>       if (acrtc) {
> >>>> -            drm_crtc_handle_vblank(&acrtc->base);
> >>>> -            amdgpu_dm_crtc_handle_crc_irq(&acrtc->base);
> >>>> -
> >>>>               acrtc_state = to_dm_crtc_state(acrtc->base.state);
> >>>>
> >>>> +            DRM_DEBUG_DRIVER("crtc:%d, vupdate-vrr:%d\n", acrtc->crtc_id,
> >>>> +                             amdgpu_dm_vrr_active(acrtc_state));
> >>>> +
> >>>> +            /* Core vblank handling at start of front-porch is only possible
> >>>> +             * in non-vrr mode, as only there vblank timestamping will give
> >>>> +             * valid results while done in front-porch. Otherwise defer it
> >>>> +             * to dm_vupdate_high_irq after end of front-porch.
> >>>> +             */
> >>>> +            if (!amdgpu_dm_vrr_active(acrtc_state))
> >>>> +                    drm_crtc_handle_vblank(&acrtc->base);
> >>>> +
> >>>> +            /* Following stuff must happen at start of vblank, for crc
> >>>> +             * computation and below-the-range btr support in vrr mode.
> >>>> +             */
> >>>> +            amdgpu_dm_crtc_handle_crc_irq(&acrtc->base);
> >>>> +
> >>>>               if (acrtc_state->stream &&
> >>>>                   acrtc_state->vrr_params.supported &&
> >>>>                   acrtc_state->freesync_config.state == VRR_STATE_ACTIVE_VARIABLE) {
> >>>> @@ -1447,6 +1486,27 @@ static int dce110_register_irq_handlers(struct amdgpu_device *adev)
> >>>>                               dm_crtc_high_irq, c_irq_params);
> >>>>       }
> >>>>
> >>>> +    /* Use VUPDATE interrupt */
> >>>> +    for (i = VISLANDS30_IV_SRCID_D1_V_UPDATE_INT; i <= VISLANDS30_IV_SRCID_D6_V_UPDATE_INT; i+=2) {
> >>>> +            r = amdgpu_irq_add_id(adev, client_id, i, &adev->vupdate_irq);
> >>>> +            if (r) {
> >>>> +                    DRM_ERROR("Failed to add vupdate irq id!\n");
> >>>> +                    return r;
> >>>> +            }
> >>>> +
> >>>> +            int_params.int_context = INTERRUPT_HIGH_IRQ_CONTEXT;
> >>>> +            int_params.irq_source =
> >>>> +                    dc_interrupt_to_irq_source(dc, i, 0);
> >>>> +
> >>>> +            c_irq_params = &adev->dm.vupdate_params[int_params.irq_source - DC_IRQ_SOURCE_VUPDATE1];
> >>>> +
> >>>> +            c_irq_params->adev = adev;
> >>>> +            c_irq_params->irq_src = int_params.irq_source;
> >>>> +
> >>>> +            amdgpu_dm_irq_register_interrupt(adev, &int_params,
> >>>> +                            dm_vupdate_high_irq, c_irq_params);
> >>>> +    }
> >>>> +
> >>>>       /* Use GRPH_PFLIP interrupt */
> >>>>       for (i = VISLANDS30_IV_SRCID_D1_GRPH_PFLIP;
> >>>>                       i <= VISLANDS30_IV_SRCID_D6_GRPH_PFLIP; i += 2) {
> >>>> @@ -1532,6 +1592,34 @@ static int dcn10_register_irq_handlers(struct amdgpu_device *adev)
> >>>>                               dm_crtc_high_irq, c_irq_params);
> >>>>       }
> >>>>
> >>>> +    /* Use VUPDATE_NO_LOCK interrupt on DCN, which seems to correspond to
> >>>> +     * the regular VUPDATE interrupt on DCE. We want DC_IRQ_SOURCE_VUPDATEx
> >>>> +     * to trigger at end of each vblank, regardless of state of the lock,
> >>>> +     * matching DCE behaviour.
> >>>> +     */
> >>>> +    for (i = DCN_1_0__SRCID__OTG0_IHC_V_UPDATE_NO_LOCK_INTERRUPT;
> >>>> +         i <= DCN_1_0__SRCID__OTG0_IHC_V_UPDATE_NO_LOCK_INTERRUPT + adev->mode_info.num_crtc - 1;
> >>>> +         i++) {
> >>>> +            r = amdgpu_irq_add_id(adev, SOC15_IH_CLIENTID_DCE, i, &adev->vupdate_irq);
> >>>> +
> >>>> +            if (r) {
> >>>> +                    DRM_ERROR("Failed to add vupdate irq id!\n");
> >>>> +                    return r;
> >>>> +            }
> >>>> +
> >>>> +            int_params.int_context = INTERRUPT_HIGH_IRQ_CONTEXT;
> >>>> +            int_params.irq_source =
> >>>> +                    dc_interrupt_to_irq_source(dc, i, 0);
> >>>> +
> >>>> +            c_irq_params = &adev->dm.vupdate_params[int_params.irq_source - DC_IRQ_SOURCE_VUPDATE1];
> >>>> +
> >>>> +            c_irq_params->adev = adev;
> >>>> +            c_irq_params->irq_src = int_params.irq_source;
> >>>> +
> >>>> +            amdgpu_dm_irq_register_interrupt(adev, &int_params,
> >>>> +                            dm_vupdate_high_irq, c_irq_params);
> >>>> +    }
> >>>> +
> >>>>       /* Use GRPH_PFLIP interrupt */
> >>>>       for (i = DCN_1_0__SRCID__HUBP0_FLIP_INTERRUPT;
> >>>>                       i <= DCN_1_0__SRCID__HUBP0_FLIP_INTERRUPT + adev->mode_info.num_crtc - 1;
> >>>> @@ -3226,12 +3314,42 @@ dm_crtc_duplicate_state(struct drm_crtc *crtc)
> >>>>       return &state->base;
> >>>>     }
> >>>>
> >>>> +static inline int dm_set_vupdate_irq(struct drm_crtc *crtc, bool enable)
> >>>> +{
> >>>> +    enum dc_irq_source irq_source;
> >>>> +    struct amdgpu_crtc *acrtc = to_amdgpu_crtc(crtc);
> >>>> +    struct amdgpu_device *adev = crtc->dev->dev_private;
> >>>> +    int rc;
> >>>> +
> >>>> +    irq_source = IRQ_TYPE_VUPDATE + acrtc->otg_inst;
> >>>> +
> >>>> +    rc = dc_interrupt_set(adev->dm.dc, irq_source, enable) ? 0 : -EBUSY;
> >>>> +
> >>>> +    DRM_DEBUG_DRIVER("%s: crtc %d - vupdate irq %sabling: r=%d\n",
> >>>> +                     __func__, acrtc->crtc_id, enable ? "en" : "dis", rc);
> >>
> >> This extra __func__ is redundant here.
> >>
> >
> > Yep. I think maybe the whole debug message is redundant by now. Maybe drop it?
> >
> >>>> +    return rc;
> >>>> +}
> >>>>
> >>>>     static inline int dm_set_vblank(struct drm_crtc *crtc, bool enable)
> >>>>     {
> >>>>       enum dc_irq_source irq_source;
> >>>>       struct amdgpu_crtc *acrtc = to_amdgpu_crtc(crtc);
> >>>>       struct amdgpu_device *adev = crtc->dev->dev_private;
> >>>> +    struct dm_crtc_state *acrtc_state = to_dm_crtc_state(crtc->state);
> >>>> +    int rc = 0;
> >>>> +
> >>>> +    if (enable) {
> >>>> +            /* vblank irq on -> Only need vupdate irq in vrr mode */
> >>>> +            if (amdgpu_dm_vrr_active(acrtc_state))
> >>>> +                    rc = dm_set_vupdate_irq(crtc, true);
> >>>> +    }
> >>>> +    else {
> >>>
> >>> should be } else {
> >>>
> >>>> +            /* vblank irq off -> vupdate irq off */
> >>>> +            rc = dm_set_vupdate_irq(crtc, false);
> >>>> +    }
> >>>> +
> >>>> +    if (rc)
> >>>> +            return rc;
> >>>>
> >>>>       irq_source = IRQ_TYPE_VBLANK + acrtc->otg_inst;
> >>>>       return dc_interrupt_set(adev->dm.dc, irq_source, enable) ? 0 : -EBUSY;
> >>>> @@ -4741,7 +4859,11 @@ static void amdgpu_dm_handle_vrr_transition(struct dm_crtc_state *old_state,
> >>>>                * While VRR is active, we must not disable vblank irq, as a
> >>>>                * reenable after disable would compute bogus vblank/pflip
> >>>>                * timestamps if it likely happened inside display front-porch.
> >>>> +             *
> >>>> +             * We also need vupdate irq for the actual core vblank handling
> >>>> +             * at end of vblank.
> >>>>                */
> >>>> +            dm_set_vupdate_irq(new_state->base.crtc, true);
> >>>>               drm_crtc_vblank_get(new_state->base.crtc);
> >>>>               DRM_DEBUG_DRIVER("%s: crtc=%u VRR off->on: Get vblank ref\n",
> >>>>                                __func__, new_state->base.crtc->base.id);
> >>>> @@ -4750,6 +4872,7 @@ static void amdgpu_dm_handle_vrr_transition(struct dm_crtc_state *old_state,
> >>>>               /* Transition VRR active -> inactive:
> >>>>                * Allow vblank irq disable again for fixed refresh rate.
> >>>>                */
> >>>> +            dm_set_vupdate_irq(new_state->base.crtc, false);
> >>>>               drm_crtc_vblank_put(new_state->base.crtc);
> >>>>               DRM_DEBUG_DRIVER("%s: crtc=%u VRR on->off: Drop vblank ref\n",
> >>>>                                __func__, new_state->base.crtc->base.id);
> >>>> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> >>>> index f741ea3..0b35f84 100644
> >>>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> >>>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> >>>> @@ -182,6 +182,15 @@ struct amdgpu_display_manager {
> >>>>       struct common_irq_params
> >>>>       vblank_params[DC_IRQ_SOURCE_VBLANK6 - DC_IRQ_SOURCE_VBLANK1 + 1];
> >>>>
> >>>> +    /**
> >>>> +     * @vupdate_params:
> >>>> +     *
> >>>> +     * Vertical update IRQ parameters, passed to registered handlers when
> >>>> +     * triggered.
> >>>> +     */
> >>>> +    struct common_irq_params
> >>>> +    vupdate_params[DC_IRQ_SOURCE_VUPDATE6 - DC_IRQ_SOURCE_VUPDATE1 + 1];
> >>>> +
> >>>>       spinlock_t irq_handler_list_table_lock;
> >>>>
> >>>>       struct backlight_device *backlight_dev;
> >>>> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c
> >>>> index cd10f77..fee7837 100644
> >>>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c
> >>>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c
> >>>> @@ -674,11 +674,30 @@ static int amdgpu_dm_set_crtc_irq_state(struct amdgpu_device *adev,
> >>>>               __func__);
> >>>>     }
> >>>>
> >>>> +static int amdgpu_dm_set_vupdate_irq_state(struct amdgpu_device *adev,
> >>>> +                                       struct amdgpu_irq_src *source,
> >>>> +                                       unsigned crtc_id,
> >>>
> >>> should be unsigned int crtc_id
> >>>
> >>>> +                                       enum amdgpu_interrupt_state state)
> >>>> +{
> >>>> +    return dm_irq_state(
> >>>> +            adev,
> >>>> +            source,
> >>>> +            crtc_id,
> >>>> +            state,
> >>>> +            IRQ_TYPE_VUPDATE,
> >>>> +            __func__);
> >>>> +}
> >>>> +
> >>>>     static const struct amdgpu_irq_src_funcs dm_crtc_irq_funcs = {
> >>>>       .set = amdgpu_dm_set_crtc_irq_state,
> >>>>       .process = amdgpu_dm_irq_handler,
> >>>>     };
> >>>>
> >>>> +static const struct amdgpu_irq_src_funcs dm_vupdate_irq_funcs = {
> >>>> +    .set = amdgpu_dm_set_vupdate_irq_state,
> >>>> +    .process = amdgpu_dm_irq_handler,
> >>>> +};
> >>>> +
> >>>>     static const struct amdgpu_irq_src_funcs dm_pageflip_irq_funcs = {
> >>>>       .set = amdgpu_dm_set_pflip_irq_state,
> >>>>       .process = amdgpu_dm_irq_handler,
> >>>> @@ -695,6 +714,9 @@ void amdgpu_dm_set_irq_funcs(struct amdgpu_device *adev)
> >>>>       adev->crtc_irq.num_types = adev->mode_info.num_crtc;
> >>>>       adev->crtc_irq.funcs = &dm_crtc_irq_funcs;
> >>>>
> >>>> +    adev->vupdate_irq.num_types = adev->mode_info.num_crtc;
> >>>> +    adev->vupdate_irq.funcs = &dm_vupdate_irq_funcs;
> >>>> +
> >>>>       adev->pageflip_irq.num_types = adev->mode_info.num_crtc;
> >>>>       adev->pageflip_irq.funcs = &dm_pageflip_irq_funcs;
> >>>>
> >>>> diff --git a/drivers/gpu/drm/amd/display/dc/irq/dce110/irq_service_dce110.c b/drivers/gpu/drm/amd/display/dc/irq/dce110/irq_service_dce110.c
> >>>> index afe0876..86987f5 100644
> >>>> --- a/drivers/gpu/drm/amd/display/dc/irq/dce110/irq_service_dce110.c
> >>>> +++ b/drivers/gpu/drm/amd/display/dc/irq/dce110/irq_service_dce110.c
> >>>> @@ -81,6 +81,11 @@ static const struct irq_source_info_funcs vblank_irq_info_funcs = {
> >>>>       .ack = NULL
> >>>>     };
> >>>>
> >>>> +static const struct irq_source_info_funcs vupdate_irq_info_funcs = {
> >>>> +    .set = NULL,
> >>>> +    .ack = NULL
> >>>> +};
> >>>> +
> >>>>     #define hpd_int_entry(reg_num)\
> >>>>       [DC_IRQ_SOURCE_HPD1 + reg_num] = {\
> >>>>               .enable_reg = mmHPD ## reg_num ## _DC_HPD_INT_CONTROL,\
> >>>> @@ -137,7 +142,7 @@ static const struct irq_source_info_funcs vblank_irq_info_funcs = {
> >>>>               CRTC_V_UPDATE_INT_STATUS__CRTC_V_UPDATE_INT_CLEAR_MASK,\
> >>>>               .ack_value =\
> >>>>               CRTC_V_UPDATE_INT_STATUS__CRTC_V_UPDATE_INT_CLEAR_MASK,\
> >>>> -            .funcs = &vblank_irq_info_funcs\
> >>>> +            .funcs = &vupdate_irq_info_funcs\
> >>>>       }
> >>>>
> >>>>     #define vblank_int_entry(reg_num)\
> >>>> diff --git a/drivers/gpu/drm/amd/display/dc/irq/dce120/irq_service_dce120.c b/drivers/gpu/drm/amd/display/dc/irq/dce120/irq_service_dce120.c
> >>>> index 1ea7256..750ba0a 100644
> >>>> --- a/drivers/gpu/drm/amd/display/dc/irq/dce120/irq_service_dce120.c
> >>>> +++ b/drivers/gpu/drm/amd/display/dc/irq/dce120/irq_service_dce120.c
> >>>> @@ -84,6 +84,11 @@ static const struct irq_source_info_funcs vblank_irq_info_funcs = {
> >>>>       .ack = NULL
> >>>>     };
> >>>>
> >>>> +static const struct irq_source_info_funcs vupdate_irq_info_funcs = {
> >>>> +    .set = NULL,
> >>>> +    .ack = NULL
> >>>> +};
> >>>> +
> >>>>     #define BASE_INNER(seg) \
> >>>>       DCE_BASE__INST0_SEG ## seg
> >>>>
> >>>> @@ -140,7 +145,7 @@ static const struct irq_source_info_funcs vblank_irq_info_funcs = {
> >>>>               IRQ_REG_ENTRY(CRTC, reg_num,\
> >>>>                       CRTC_INTERRUPT_CONTROL, CRTC_V_UPDATE_INT_MSK,\
> >>>>                       CRTC_V_UPDATE_INT_STATUS, CRTC_V_UPDATE_INT_CLEAR),\
> >>>> -            .funcs = &vblank_irq_info_funcs\
> >>>> +            .funcs = &vupdate_irq_info_funcs\
> >>>>       }
> >>>>
> >>>>     #define vblank_int_entry(reg_num)\
> >>>> diff --git a/drivers/gpu/drm/amd/display/dc/irq/dce80/irq_service_dce80.c b/drivers/gpu/drm/amd/display/dc/irq/dce80/irq_service_dce80.c
> >>>> index 8a2066c..de218fe 100644
> >>>> --- a/drivers/gpu/drm/amd/display/dc/irq/dce80/irq_service_dce80.c
> >>>> +++ b/drivers/gpu/drm/amd/display/dc/irq/dce80/irq_service_dce80.c
> >>>> @@ -84,6 +84,10 @@ static const struct irq_source_info_funcs vblank_irq_info_funcs = {
> >>>>       .ack = NULL
> >>>>     };
> >>>>
> >>>> +static const struct irq_source_info_funcs vupdate_irq_info_funcs = {
> >>>> +    .set = NULL,
> >>>> +    .ack = NULL
> >>>> +};
> >>>>
> >>>>     #define hpd_int_entry(reg_num)\
> >>>>       [DC_IRQ_SOURCE_INVALID + reg_num] = {\
> >>>> @@ -142,7 +146,7 @@ static const struct irq_source_info_funcs vblank_irq_info_funcs = {
> >>>>               CRTC_V_UPDATE_INT_STATUS__CRTC_V_UPDATE_INT_CLEAR_MASK,\
> >>>>               .ack_value =\
> >>>>               CRTC_V_UPDATE_INT_STATUS__CRTC_V_UPDATE_INT_CLEAR_MASK,\
> >>>> -            .funcs = &vblank_irq_info_funcs\
> >>>> +            .funcs = &vupdate_irq_info_funcs\
> >>>>       }
> >>>>
> >>>>     #define vblank_int_entry(reg_num)\
> >>>> diff --git a/drivers/gpu/drm/amd/display/dc/irq/dcn10/irq_service_dcn10.c b/drivers/gpu/drm/amd/display/dc/irq/dcn10/irq_service_dcn10.c
> >>>> index e04ae49..10ac6de 100644
> >>>> --- a/drivers/gpu/drm/amd/display/dc/irq/dcn10/irq_service_dcn10.c
> >>>> +++ b/drivers/gpu/drm/amd/display/dc/irq/dcn10/irq_service_dcn10.c
> >>>> @@ -56,6 +56,18 @@ enum dc_irq_source to_dal_irq_source_dcn10(
> >>>>               return DC_IRQ_SOURCE_VBLANK5;
> >>>>       case DCN_1_0__SRCID__DC_D6_OTG_VSTARTUP:
> >>>>               return DC_IRQ_SOURCE_VBLANK6;
> >>>> +    case DCN_1_0__SRCID__OTG0_IHC_V_UPDATE_NO_LOCK_INTERRUPT:
> >>>> +            return DC_IRQ_SOURCE_VUPDATE1;
> >>>> +    case DCN_1_0__SRCID__OTG1_IHC_V_UPDATE_NO_LOCK_INTERRUPT:
> >>>> +            return DC_IRQ_SOURCE_VUPDATE2;
> >>>> +    case DCN_1_0__SRCID__OTG2_IHC_V_UPDATE_NO_LOCK_INTERRUPT:
> >>>> +            return DC_IRQ_SOURCE_VUPDATE3;
> >>>> +    case DCN_1_0__SRCID__OTG3_IHC_V_UPDATE_NO_LOCK_INTERRUPT:
> >>>> +            return DC_IRQ_SOURCE_VUPDATE4;
> >>>> +    case DCN_1_0__SRCID__OTG4_IHC_V_UPDATE_NO_LOCK_INTERRUPT:
> >>>> +            return DC_IRQ_SOURCE_VUPDATE5;
> >>>> +    case DCN_1_0__SRCID__OTG5_IHC_V_UPDATE_NO_LOCK_INTERRUPT:
> >>>> +            return DC_IRQ_SOURCE_VUPDATE6;
> >>
> >> I'm not sure we necessarily want to reuse the same
> >> DC_IRQ_SOURCE_VUPDATE1...6 definitions here again when it's really
> >> V_UPDATE_NO_LOCK.
> >>
> >
> > Hm. The problem is that if we use different ones for DCE and DCN we
> > need special-case handling in amdgpu_dm.c, e.g., in
> > amdgpu_dm_set_vupdate_irq_state() and dm_set_vupdate_irq() to detect
> > if it is caling DCE or DCN (how to detect this?) to select different
> > irq sources IRQ_TYPE_VUPDATE vs IRQ_TYPE_VUPDATE_NO_LOCK and such?
> > And definitions like "struct amdgpu_irq_src vupdate_irq;" should then
> > also exist twice as vupdate_irq and vupdate_irq_no_lock for correct
> > naming?
> >
> > Or we'd name the IRQ source and all relevant data structures and
> > functions something like DC_IRQ_SOURCE_VBLANK_END1..6 to describe what
> > it signals instead of to what it corresponds in hardware? That would
> > be what was done with the regular DC_IRQ_SOURCE_VBLANK1..6. It signals
> > start of vblank, but the underlying hw interrupts are actually a
> > properly programmed VLINE0 irq on DCE and a VSTARTUP irq on DCN.
>
>
> Ah, I see what you mean. Maybe this is for the better to share the same
> names then. I'll defer this to Harry.
>
> >
> > Of course this all assumes we need to use the NO_LOCK variant on DCN?
> > We haven't tested what the regular VUPDATE_IRQ does, because i don't
> > have a suitable test machine, and my use of the NO_LOCK variant was
> > just based on my interpretation of this little comment in the DCN
> > header file:
> >
> > #define DCN_1_0__SRCID__OTG0_IHC_V_UPDATE_NO_LOCK_INTERRUPT 0x57 //
> > "OTG0 VUPDATE event without lock interrupt, VUPDATE is update event
> > for double buffered registers"
> >
> > and the absence of any explanatory comment in the define of regular V_UPDATE:
> >
> > #define DCN_1_0__SRCID__DC_D1_OTG_V_UPDATE 0x18 // D1 : OTG V_update
> > OTG1_IHC_V_UPDATE_INTERRUPT
> >
> > I assumed the NO_LOCK means not affected by the state of any of the hw
> > locks, so regular V_UPDATE might be affected by them. You agreed with
> > that, but we never tested what regular V_UPDATE would do on DCN. Do we
> > actually know for sure from hw specs that it would not work, ie. not
> > unconditionally fire the IRQ at every end of VBLANK, as we need?
>
> FWIW, I did try your original patches with V_UPDATE. I don't know off
> the top of my head what specifically V_UPDATE does that V_UPDATE_NO_LOCK
> doesn't, but at the very least the HW won't be flipping anything to the
> screen if you're using the former. You'll end up with a static screen
> that looks like a system hang.
>

Yes, but that was because that iteration of the patch had a bug, where
i defined the irq sources / irq hw sources as _NO_LOCK variants as i
intended, but forgot to adapt the irq en/disable register macros. You
fixed my bug during your testing and so we know the _NO_LOCK variant
works perfectly for our purpose. But we never tesed if the standard
variant would have worked just as well.

I will test this later today, because since today i'm the proud owner
of a PC with Ryzen 5 2400G with Vega11 Raven / DCN-1.0 :). So i'll
give it a try. Would be good though if you could have a look at the
hardware docs i assume you have internally to verify what the V_UPDATE
irq hw source actually does?

-mario

> Nicholas Kazlauskas
>
> >
> >
> >>>>       case DCN_1_0__SRCID__HUBP0_FLIP_INTERRUPT:
> >>>>               return DC_IRQ_SOURCE_PFLIP1;
> >>>>       case DCN_1_0__SRCID__HUBP1_FLIP_INTERRUPT:
> >>>> @@ -153,6 +165,11 @@ static const struct irq_source_info_funcs vblank_irq_info_funcs = {
> >>>>       .ack = NULL
> >>>>     };
> >>>>
> >>>> +static const struct irq_source_info_funcs vupdate_no_lock_irq_info_funcs = {
> >>>> +    .set = NULL,
> >>>> +    .ack = NULL
> >>>> +};
> >>>> +
> >>>>     #define BASE_INNER(seg) \
> >>>>       DCE_BASE__INST0_SEG ## seg
> >>>>
> >>>> @@ -203,12 +220,15 @@ static const struct irq_source_info_funcs vblank_irq_info_funcs = {
> >>>>               .funcs = &pflip_irq_info_funcs\
> >>>>       }
> >>>>
> >>>> -#define vupdate_int_entry(reg_num)\
> >>>> +/* vupdate_no_lock_int_entry maps to DC_IRQ_SOURCE_VUPDATEx, to match semantic
> >>>> + * of DCE's DC_IRQ_SOURCE_VUPDATEx.
> >>>> + */
> >>>> +#define vupdate_no_lock_int_entry(reg_num)\
> >>>>       [DC_IRQ_SOURCE_VUPDATE1 + reg_num] = {\
> >>>>               IRQ_REG_ENTRY(OTG, reg_num,\
> >>>> -                    OTG_GLOBAL_SYNC_STATUS, VUPDATE_INT_EN,\
> >>>> -                    OTG_GLOBAL_SYNC_STATUS, VUPDATE_EVENT_CLEAR),\
> >>>> -            .funcs = &vblank_irq_info_funcs\
> >>>> +                    OTG_GLOBAL_SYNC_STATUS, VUPDATE_NO_LOCK_INT_EN,\
> >>>> +                    OTG_GLOBAL_SYNC_STATUS, VUPDATE_NO_LOCK_EVENT_CLEAR),\
> >>>> +            .funcs = &vupdate_no_lock_irq_info_funcs\
> >>>>       }
> >>>>
> >>>>     #define vblank_int_entry(reg_num)\
> >>>> @@ -315,12 +335,12 @@ irq_source_info_dcn10[DAL_IRQ_SOURCES_NUMBER] = {
> >>>>       dc_underflow_int_entry(6),
> >>>>       [DC_IRQ_SOURCE_DMCU_SCP] = dummy_irq_entry(),
> >>>>       [DC_IRQ_SOURCE_VBIOS_SW] = dummy_irq_entry(),
> >>>> -    vupdate_int_entry(0),
> >>>> -    vupdate_int_entry(1),
> >>>> -    vupdate_int_entry(2),
> >>>> -    vupdate_int_entry(3),
> >>>> -    vupdate_int_entry(4),
> >>>> -    vupdate_int_entry(5),
> >>
> >> I don't think we should be necessarily dropping these, but I guess it
> >> could go either way since these IRQs technically aren't defined.
> >>
> >
> > We could keep both definitions around, original vupdate_int_entry +
> > the new vupdate_no_lock_int_entry.
> >
> > -mario
> >
> >>>> +    vupdate_no_lock_int_entry(0),
> >>>> +    vupdate_no_lock_int_entry(1),
> >>>> +    vupdate_no_lock_int_entry(2),
> >>>> +    vupdate_no_lock_int_entry(3),
> >>>> +    vupdate_no_lock_int_entry(4),
> >>>> +    vupdate_no_lock_int_entry(5),
> >>>>       vblank_int_entry(0),
> >>>>       vblank_int_entry(1),
> >>>>       vblank_int_entry(2),
> >>>>
> >>>
> >>> Nicholas Kazlauskas
> >>> _______________________________________________
> >>> amd-gfx mailing list
> >>> amd-gfx at lists.freedesktop.org
> >>> https://lists.freedesktop.org/mailman/listinfo/amd-gfx
> >>>
> >>
>


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