[PATCH v4 18/25] drm/msm/dpu: Reserve resources for CWB
Dmitry Baryshkov
dmitry.baryshkov at linaro.org
Sun Dec 29 04:47:02 UTC 2024
On Thu, Dec 26, 2024 at 02:49:28PM -0800, Jessica Zhang wrote:
>
>
> On 12/20/2024 5:07 PM, Dmitry Baryshkov wrote:
> > On Fri, Dec 20, 2024 at 04:12:29PM -0800, Jessica Zhang wrote:
> > >
> > >
> > > On 12/19/2024 9:52 PM, Dmitry Baryshkov wrote:
> > > > On Mon, Dec 16, 2024 at 04:43:29PM -0800, Jessica Zhang wrote:
> > > > > Add support for RM to reserve dedicated CWB PINGPONGs and CWB muxes
> > > > >
> > > > > For concurrent writeback, even-indexed CWB muxes must be assigned to
> > > > > even-indexed LMs and odd-indexed CWB muxes for odd-indexed LMs. The same
> > > > > even/odd rule applies for dedicated CWB PINGPONGs.
> > > > >
> > > > > Track the CWB muxes in the global state and add a CWB-specific helper to
> > > > > reserve the correct CWB muxes and dedicated PINGPONGs following the
> > > > > even/odd rule.
> > > > >
> > > > > Signed-off-by: Jessica Zhang <quic_jesszhan at quicinc.com>
> > > > > ---
> > > > > drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 34 ++++++++++--
> > > > > drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h | 2 +
> > > > > drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h | 1 +
> > > > > drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c | 83 +++++++++++++++++++++++++++++
> > > > > 4 files changed, 116 insertions(+), 4 deletions(-)
> > > > >
> > > > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > > > > index a895d48fe81ccc71d265e089992786e8b6268b1b..a95dc1f0c6a422485c7ba98743e944e1a4f43539 100644
> > > > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > > > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > > > > @@ -2,7 +2,7 @@
> > > > > /*
> > > > > * Copyright (C) 2013 Red Hat
> > > > > * Copyright (c) 2014-2018, 2020-2021 The Linux Foundation. All rights reserved.
> > > > > - * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
> > > > > + * Copyright (c) 2022-2024 Qualcomm Innovation Center, Inc. All rights reserved.
> > > > > *
> > > > > * Author: Rob Clark <robdclark at gmail.com>
> > > > > */
> > > > > @@ -28,6 +28,7 @@
> > > > > #include "dpu_hw_dsc.h"
> > > > > #include "dpu_hw_merge3d.h"
> > > > > #include "dpu_hw_cdm.h"
> > > > > +#include "dpu_hw_cwb.h"
> > > > > #include "dpu_formats.h"
> > > > > #include "dpu_encoder_phys.h"
> > > > > #include "dpu_crtc.h"
> > > > > @@ -133,6 +134,9 @@ enum dpu_enc_rc_states {
> > > > > * @cur_slave: As above but for the slave encoder.
> > > > > * @hw_pp: Handle to the pingpong blocks used for the display. No.
> > > > > * pingpong blocks can be different than num_phys_encs.
> > > > > + * @hw_cwb: Handle to the CWB muxes used for concurrent writeback
> > > > > + * display. Number of CWB muxes can be different than
> > > > > + * num_phys_encs.
> > > > > * @hw_dsc: Handle to the DSC blocks used for the display.
> > > > > * @dsc_mask: Bitmask of used DSC blocks.
> > > > > * @intfs_swapped: Whether or not the phys_enc interfaces have been swapped
> > > > > @@ -177,6 +181,7 @@ struct dpu_encoder_virt {
> > > > > struct dpu_encoder_phys *cur_master;
> > > > > struct dpu_encoder_phys *cur_slave;
> > > > > struct dpu_hw_pingpong *hw_pp[MAX_CHANNELS_PER_ENC];
> > > > > + struct dpu_hw_cwb *hw_cwb[MAX_CHANNELS_PER_ENC];
> > > > > struct dpu_hw_dsc *hw_dsc[MAX_CHANNELS_PER_ENC];
> > > > > unsigned int dsc_mask;
> > > > > @@ -1138,7 +1143,10 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
> > > > > struct dpu_hw_blk *hw_pp[MAX_CHANNELS_PER_ENC];
> > > > > struct dpu_hw_blk *hw_ctl[MAX_CHANNELS_PER_ENC];
> > > > > struct dpu_hw_blk *hw_dsc[MAX_CHANNELS_PER_ENC];
> > > > > + struct dpu_hw_blk *hw_cwb[MAX_CHANNELS_PER_ENC];
> > > > > int num_pp, num_dsc, num_ctl;
> > > > > + int num_cwb = 0;
> > > > > + bool is_cwb_encoder;
> > > > > unsigned int dsc_mask = 0;
> > > > > int i;
> > > > > @@ -1152,6 +1160,8 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
> > > > > priv = drm_enc->dev->dev_private;
> > > > > dpu_kms = to_dpu_kms(priv->kms);
> > > > > + is_cwb_encoder = drm_crtc_in_clone_mode(crtc_state) &&
> > > > > + dpu_enc->disp_info.intf_type == INTF_WB;
> > > > > global_state = dpu_kms_get_existing_global_state(dpu_kms);
> > > > > if (IS_ERR_OR_NULL(global_state)) {
> > > > > @@ -1162,9 +1172,25 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
> > > > > trace_dpu_enc_mode_set(DRMID(drm_enc));
> > > > > /* Query resource that have been reserved in atomic check step. */
> > > > > - num_pp = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
> > > > > - drm_enc->crtc, DPU_HW_BLK_PINGPONG, hw_pp,
> > > > > - ARRAY_SIZE(hw_pp));
> > > > > + if (is_cwb_encoder) {
> > > > > + num_pp = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
> > > > > + drm_enc->crtc,
> > > > > + DPU_HW_BLK_DCWB_PINGPONG,
> > > > > + hw_pp, ARRAY_SIZE(hw_pp));
> > > > > + num_cwb = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
> > > > > + drm_enc->crtc,
> > > > > + DPU_HW_BLK_CWB,
> > > > > + hw_cwb, ARRAY_SIZE(hw_cwb));
> > > > > + } else {
> > > > > + num_pp = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
> > > > > + drm_enc->crtc,
> > > > > + DPU_HW_BLK_PINGPONG, hw_pp,
> > > > > + ARRAY_SIZE(hw_pp));
> > > > > + }
> > > > > +
> > > > > + for (i = 0; i < num_cwb; i++)
> > > > > + dpu_enc->hw_cwb[i] = to_dpu_hw_cwb(hw_cwb[i]);
> > > > > +
> > > > > num_ctl = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
> > > > > drm_enc->crtc, DPU_HW_BLK_CTL, hw_ctl, ARRAY_SIZE(hw_ctl));
> > > > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
> > > > > index ba7bb05efe9b8cac01a908e53121117e130f91ec..8d820cd1b5545d247515763039b341184e814e32 100644
> > > > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
> > > > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
> > > > > @@ -77,12 +77,14 @@ enum dpu_hw_blk_type {
> > > > > DPU_HW_BLK_LM,
> > > > > DPU_HW_BLK_CTL,
> > > > > DPU_HW_BLK_PINGPONG,
> > > > > + DPU_HW_BLK_DCWB_PINGPONG,
> > > > > DPU_HW_BLK_INTF,
> > > > > DPU_HW_BLK_WB,
> > > > > DPU_HW_BLK_DSPP,
> > > > > DPU_HW_BLK_MERGE_3D,
> > > > > DPU_HW_BLK_DSC,
> > > > > DPU_HW_BLK_CDM,
> > > > > + DPU_HW_BLK_CWB,
> > > > > DPU_HW_BLK_MAX,
> > > > > };
> > > > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
> > > > > index 48d756d8f8c6e4ab94b72bac0418320f7dc8cda8..1fc8abda927fc094b369e0d1efc795b71d6a7fcb 100644
> > > > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
> > > > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
> > > > > @@ -128,6 +128,7 @@ struct dpu_global_state {
> > > > > uint32_t dspp_to_crtc_id[DSPP_MAX - DSPP_0];
> > > > > uint32_t dsc_to_crtc_id[DSC_MAX - DSC_0];
> > > > > uint32_t cdm_to_crtc_id;
> > > > > + uint32_t cwb_to_crtc_id[CWB_MAX - CWB_0];
> > > > > };
> > > > > struct dpu_global_state
> > > > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
> > > > > index 85adaf256b2c705d2d7df378b6ffc0e578f52bc3..ead24bb0ceb5d8ec4705f0d32330294d0b45b216 100644
> > > > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
> > > > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
> > > > > @@ -234,6 +234,55 @@ static int _dpu_rm_get_lm_peer(struct dpu_rm *rm, int primary_idx)
> > > > > return -EINVAL;
> > > > > }
> > > > > +static int _dpu_rm_reserve_cwb_mux_and_pingpongs(struct dpu_rm *rm,
> > > > > + struct dpu_global_state *global_state,
> > > > > + uint32_t crtc_id,
> > > > > + struct msm_display_topology *topology)
> > > > > +{
> > > > > + int num_cwb_pp = topology->num_lm, cwb_pp_count = 0;
> > > > > + int cwb_pp_start_idx = PINGPONG_CWB_0 - PINGPONG_0;
> > > > > + int cwb_pp_idx[MAX_BLOCKS];
> > > > > + int cwb_mux_idx[MAX_BLOCKS];
> > > > > +
> > > > > + /*
> > > > > + * Reserve additional dedicated CWB PINGPONG blocks and muxes for each
> > > > > + * mixer
> > > > > + *
> > > > > + * TODO: add support reserving resources for platforms with no
> > > > > + * PINGPONG_CWB
> > > >
> > > > What about doing it other way around: allocate CWBs first as required
> > > > (even/odd, proper count, etc). Then for each of CWBs allocate a PP block
> > > > (I think it's enough to simply make CWB blocks have a corresponding PP
> > > > index as a property). This way the driver can handle both legacy and
> > > > current platforms.
> > >
> > > Hi Dmitry,
> > >
> > > Sorry if I'm misunderstanding your suggestion, but the main change needed to
> > > support platforms with no dedicated PINGPONG_CWB is where in the
> > > rm->pingpong_blks list to start assigning pingpong blocks for the CWB mux.
> > > I'm not sure how changing the order in which CWBs and the pingpong blocks
> > > are assigned will address that.
> > >
> > > (FWIW, the only change necessary to add support for non-dedicated
> > > PINGPONG_CWBs platforms for this function should just be changing the
> > > initialization value of cwb_pp_start_idx)
> >
> > If I remember correctly, we have identified several generations of DPU
> > wrt. CWB handling:
> > - 8.1+ (or 8.0+?), DCWB, dedicated PP blocks
> > - 7.2, dedicated PP_1?
> > - 5.0+, shared PP blocks
> > - older DPUs, special handling of PP
> >
> > If the driver allocates PP first and then first it has to allocated PP
> > (in a platform-specific way) and then go from PINGPONG to CWB (in a
> > platform-specific way). If CWB is allocated first, then you have only
> > one platform-specific piece of code that gets PINGPONG for the CWB (and
> > as this function is called after the CWB allocation, the major part of
> > the CWB / PP allocation is generic).
>
> The issue with breaking this into separate helpers/functions is that the CWB
> mux and PPB indices are dependent on each other. But I agree that we can
> reserve CWB mux and the PPBs in 2 separate loops within this helper to
> minimize the special platform-specific handling.
Doesn't it just PPB depend on CWB?
>
> Also wanted to note that the comment doc on the PPB odd/even rule is
> inaccurate -- technically the odd/even rule applies specifically to the CWB
> mux as odd/even LMs are hardwired to their respective CWB muxes. Will
> correct the comment doc to be more accurate.
Yes, please fix that.
>
> Thanks,
>
> Jessica Zhang
>
--
With best wishes
Dmitry
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