drivers/gpu/drm/msm/disp/mdp5/mdp5_mixer.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2017 The Linux Foundation. All rights reserved.
   4  */
   5
   6 #include "mdp5_kms.h"
   7
   8 /*
   9  * As of now, there are only 2 combinations possible for source split:
  10  *
  11  * Left | Right
  12  * -----|------
  13  *  LM0 | LM1
  14  *  LM2 | LM5
  15  *
  16  */
  17 static int lm_right_pair[] = { 1, -1, 5, -1, -1, -1 };
  18
  19 static int get_right_pair_idx(struct mdp5_kms *mdp5_kms, int lm)
  20 {
  21         int i;
  22         int pair_lm;
  23
  24         pair_lm = lm_right_pair[lm];
  25         if (pair_lm < 0)
  26                 return -EINVAL;
  27
  28         for (i = 0; i < mdp5_kms->num_hwmixers; i++) {
  29                 struct mdp5_hw_mixer *mixer = mdp5_kms->hwmixers[i];
  30
  31                 if (mixer->lm == pair_lm)
  32                         return mixer->idx;
  33         }
  34
  35         return -1;
  36 }
  37
  38 int mdp5_mixer_assign(struct drm_atomic_state *s, struct drm_crtc *crtc,
  39                       uint32_t caps, struct mdp5_hw_mixer **mixer,
  40                       struct mdp5_hw_mixer **r_mixer)
  41 {
  42         struct msm_drm_private *priv = s->dev->dev_private;
  43         struct mdp5_kms *mdp5_kms = to_mdp5_kms(to_mdp_kms(priv->kms));
  44         struct mdp5_global_state *global_state = mdp5_get_global_state(s);
  45         struct mdp5_hw_mixer_state *new_state;
  46         int i;
  47
  48         if (IS_ERR(global_state))
  49                 return PTR_ERR(global_state);
  50
  51         new_state = &global_state->hwmixer;
  52
  53         for (i = 0; i < mdp5_kms->num_hwmixers; i++) {
  54                 struct mdp5_hw_mixer *cur = mdp5_kms->hwmixers[i];
  55
  56                 /*
  57                  * skip if already in-use by a different CRTC. If there is a
  58                  * mixer already assigned to this CRTC, it means this call is
  59                  * a request to get an additional right mixer. Assume that the
  60                  * existing mixer is the 'left' one, and try to see if we can
  61                  * get its corresponding 'right' pair.
  62                  */
  63                 if (new_state->hwmixer_to_crtc[cur->idx] &&
  64                     new_state->hwmixer_to_crtc[cur->idx] != crtc)
  65                         continue;
  66
  67                 /* skip if doesn't support some required caps: */
  68                 if (caps & ~cur->caps)
  69                         continue;
  70
  71                 if (r_mixer) {
  72                         int pair_idx;
  73
  74                         pair_idx = get_right_pair_idx(mdp5_kms, cur->lm);
  75                         if (pair_idx < 0)
  76                                 return -EINVAL;
  77
  78                         if (new_state->hwmixer_to_crtc[pair_idx])
  79                                 continue;
  80
  81                         *r_mixer = mdp5_kms->hwmixers[pair_idx];
  82                 }
  83
  84                 /*
  85                  * prefer a pair-able LM over an unpairable one. We can
  86                  * switch the CRTC from Normal mode to Source Split mode
  87                  * without requiring a full modeset if we had already
  88                  * assigned this CRTC a pair-able LM.
  89                  *
  90                  * TODO: There will be assignment sequences which would
  91                  * result in the CRTC requiring a full modeset, even
  92                  * if we have the LM resources to prevent it. For a platform
  93                  * with a few displays, we don't run out of pair-able LMs
  94                  * so easily. For now, ignore the possibility of requiring
  95                  * a full modeset.
  96                  */
  97                 if (!(*mixer) || cur->caps & MDP_LM_CAP_PAIR)
  98                         *mixer = cur;
  99         }
 100
 101         if (!(*mixer))
 102                 return -ENOMEM;
 103
 104         if (r_mixer && !(*r_mixer))
 105                 return -ENOMEM;
 106
 107         DBG("assigning Layer Mixer %d to crtc %s", (*mixer)->lm, crtc->name);
 108
 109         new_state->hwmixer_to_crtc[(*mixer)->idx] = crtc;
 110         if (r_mixer) {
 111                 DBG("assigning Right Layer Mixer %d to crtc %s", (*r_mixer)->lm,
 112                     crtc->name);
 113                 new_state->hwmixer_to_crtc[(*r_mixer)->idx] = crtc;
 114         }
 115
 116         return 0;
 117 }
 118
 119 void mdp5_mixer_release(struct drm_atomic_state *s, struct mdp5_hw_mixer *mixer)
 120 {
 121         struct mdp5_global_state *global_state = mdp5_get_global_state(s);
 122         struct mdp5_hw_mixer_state *new_state = &global_state->hwmixer;
 123
 124         if (!mixer)
 125                 return;
 126
 127         if (WARN_ON(!new_state->hwmixer_to_crtc[mixer->idx]))
 128                 return;
 129
 130         DBG("%s: release from crtc %s", mixer->name,
 131             new_state->hwmixer_to_crtc[mixer->idx]->name);
 132
 133         new_state->hwmixer_to_crtc[mixer->idx] = NULL;
 134 }
 135
 136 void mdp5_mixer_destroy(struct mdp5_hw_mixer *mixer)
 137 {
 138         kfree(mixer);
 139 }
 140
 141 static const char * const mixer_names[] = {
 142         "LM0", "LM1", "LM2", "LM3", "LM4", "LM5",
 143 };
 144
 145 struct mdp5_hw_mixer *mdp5_mixer_init(const struct mdp5_lm_instance *lm)
 146 {
 147         struct mdp5_hw_mixer *mixer;
 148
 149         mixer = kzalloc(sizeof(*mixer), GFP_KERNEL);
 150         if (!mixer)
 151                 return ERR_PTR(-ENOMEM);
 152
 153         mixer->name = mixer_names[lm->id];
 154         mixer->lm = lm->id;
 155         mixer->caps = lm->caps;
 156         mixer->pp = lm->pp;
 157         mixer->dspp = lm->dspp;
 158         mixer->flush_mask = mdp_ctl_flush_mask_lm(lm->id);
 159
 160         return mixer;
 161 }