1/* 2 * Copyright (c) 2014, The Linux Foundation. All rights reserved. 3 * Copyright (C) 2013 Red Hat 4 * Author: Rob Clark <robdclark@gmail.com> 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 as published by 8 * the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 13 * more details. 14 * 15 * You should have received a copy of the GNU General Public License along with 16 * this program. If not, see <http://www.gnu.org/licenses/>. 17 */ 18 19 20#include "mdp5_kms.h" 21#include "mdp5_smp.h" 22 23 24/* SMP - Shared Memory Pool 25 * 26 * These are shared between all the clients, where each plane in a 27 * scanout buffer is a SMP client. Ie. scanout of 3 plane I420 on 28 * pipe VIG0 => 3 clients: VIG0_Y, VIG0_CB, VIG0_CR. 29 * 30 * Based on the size of the attached scanout buffer, a certain # of 31 * blocks must be allocated to that client out of the shared pool. 32 * 33 * In some hw, some blocks are statically allocated for certain pipes 34 * and CANNOT be re-allocated (eg: MMB0 and MMB1 both tied to RGB0). 35 * 36 * For each block that can be dynamically allocated, it can be either 37 * free, or pending/in-use by a client. The updates happen in three steps: 38 * 39 * 1) mdp5_smp_request(): 40 * When plane scanout is setup, calculate required number of 41 * blocks needed per client, and request. Blocks not inuse or 42 * pending by any other client are added to client's pending 43 * set. 44 * 45 * 2) mdp5_smp_configure(): 46 * As hw is programmed, before FLUSH, MDP5_MDP_SMP_ALLOC registers 47 * are configured for the union(pending, inuse) 48 * 49 * 3) mdp5_smp_commit(): 50 * After next vblank, copy pending -> inuse. Optionally update 51 * MDP5_SMP_ALLOC registers if there are newly unused blocks 52 * 53 * On the next vblank after changes have been committed to hw, the 54 * client's pending blocks become it's in-use blocks (and no-longer 55 * in-use blocks become available to other clients). 56 * 57 * btw, hurray for confusing overloaded acronyms! :-/ 58 * 59 * NOTE: for atomic modeset/pageflip NONBLOCK operations, step #1 60 * should happen at (or before)? atomic->check(). And we'd need 61 * an API to discard previous requests if update is aborted or 62 * (test-only). 63 * 64 * TODO would perhaps be nice to have debugfs to dump out kernel 65 * inuse and pending state of all clients.. 66 */ 67 68struct mdp5_smp { 69 struct drm_device *dev; 70 71 int blk_cnt; 72 int blk_size; 73 74 spinlock_t state_lock; 75 mdp5_smp_state_t state; /* to track smp allocation amongst pipes: */ 76 77 struct mdp5_client_smp_state client_state[MAX_CLIENTS]; 78}; 79 80static inline 81struct mdp5_kms *get_kms(struct mdp5_smp *smp) 82{ 83 struct msm_drm_private *priv = smp->dev->dev_private; 84 85 return to_mdp5_kms(to_mdp_kms(priv->kms)); 86} 87 88static inline u32 pipe2client(enum mdp5_pipe pipe, int plane) 89{ 90#define CID_UNUSED 0 91 92 if (WARN_ON(plane >= pipe2nclients(pipe))) 93 return CID_UNUSED; 94 95 /* 96 * Note on SMP clients: 97 * For ViG pipes, fetch Y/Cr/Cb-components clients are always 98 * consecutive, and in that order. 99 * 100 * e.g.: 101 * if mdp5_cfg->smp.clients[SSPP_VIG0] = N, 102 * Y plane's client ID is N 103 * Cr plane's client ID is N + 1 104 * Cb plane's client ID is N + 2 105 */ 106 107 return mdp5_cfg->smp.clients[pipe] + plane; 108} 109 110/* step #1: update # of blocks pending for the client: */ 111static int smp_request_block(struct mdp5_smp *smp, 112 u32 cid, int nblks) 113{ 114 struct mdp5_kms *mdp5_kms = get_kms(smp); 115 const struct mdp5_cfg_hw *hw_cfg; 116 struct mdp5_client_smp_state *ps = &smp->client_state[cid]; 117 int i, ret, avail, cur_nblks, cnt = smp->blk_cnt; 118 int reserved; 119 unsigned long flags; 120 121 hw_cfg = mdp5_cfg_get_hw_config(mdp5_kms->cfg); 122 reserved = hw_cfg->smp.reserved[cid]; 123 124 spin_lock_irqsave(&smp->state_lock, flags); 125 126 if (reserved) { 127 nblks = max(0, nblks - reserved); 128 DBG("%d MMBs allocated (%d reserved)", nblks, reserved); 129 } 130 131 avail = cnt - bitmap_weight(smp->state, cnt); 132 if (nblks > avail) { 133 dev_err(mdp5_kms->dev->dev, "out of blks (req=%d > avail=%d)\n", 134 nblks, avail); 135 ret = -ENOSPC; 136 goto fail; 137 } 138 139 cur_nblks = bitmap_weight(ps->pending, cnt); 140 if (nblks > cur_nblks) { 141 /* grow the existing pending reservation: */ 142 for (i = cur_nblks; i < nblks; i++) { 143 int blk = find_first_zero_bit(smp->state, cnt); 144 set_bit(blk, ps->pending); 145 set_bit(blk, smp->state); 146 } 147 } else { 148 /* shrink the existing pending reservation: */ 149 for (i = cur_nblks; i > nblks; i--) { 150 int blk = find_first_bit(ps->pending, cnt); 151 clear_bit(blk, ps->pending); 152 /* don't clear in global smp_state until _commit() */ 153 } 154 } 155 156fail: 157 spin_unlock_irqrestore(&smp->state_lock, flags); 158 return 0; 159} 160 161static void set_fifo_thresholds(struct mdp5_smp *smp, 162 enum mdp5_pipe pipe, int nblks) 163{ 164 struct mdp5_kms *mdp5_kms = get_kms(smp); 165 u32 smp_entries_per_blk = smp->blk_size / (128 / BITS_PER_BYTE); 166 u32 val; 167 168 /* 1/4 of SMP pool that is being fetched */ 169 val = (nblks * smp_entries_per_blk) / 4; 170 171 mdp5_write(mdp5_kms, REG_MDP5_PIPE_REQPRIO_FIFO_WM_0(pipe), val * 1); 172 mdp5_write(mdp5_kms, REG_MDP5_PIPE_REQPRIO_FIFO_WM_1(pipe), val * 2); 173 mdp5_write(mdp5_kms, REG_MDP5_PIPE_REQPRIO_FIFO_WM_2(pipe), val * 3); 174} 175 176/* 177 * NOTE: looks like if horizontal decimation is used (if we supported that) 178 * then the width used to calculate SMP block requirements is the post- 179 * decimated width. Ie. SMP buffering sits downstream of decimation (which 180 * presumably happens during the dma from scanout buffer). 181 */ 182int mdp5_smp_request(struct mdp5_smp *smp, enum mdp5_pipe pipe, u32 fmt, u32 width) 183{ 184 struct mdp5_kms *mdp5_kms = get_kms(smp); 185 struct drm_device *dev = mdp5_kms->dev; 186 int rev = mdp5_cfg_get_hw_rev(mdp5_kms->cfg); 187 int i, hsub, nplanes, nlines, nblks, ret; 188 189 nplanes = drm_format_num_planes(fmt); 190 hsub = drm_format_horz_chroma_subsampling(fmt); 191 192 /* different if BWC (compressed framebuffer?) enabled: */ 193 nlines = 2; 194 195 for (i = 0, nblks = 0; i < nplanes; i++) { 196 int n, fetch_stride, cpp; 197 198 cpp = drm_format_plane_cpp(fmt, i); 199 fetch_stride = width * cpp / (i ? hsub : 1); 200 201 n = DIV_ROUND_UP(fetch_stride * nlines, smp->blk_size); 202 203 /* for hw rev v1.00 */ 204 if (rev == 0) 205 n = roundup_pow_of_two(n); 206 207 DBG("%s[%d]: request %d SMP blocks", pipe2name(pipe), i, n); 208 ret = smp_request_block(smp, pipe2client(pipe, i), n); 209 if (ret) { 210 dev_err(dev->dev, "Cannot allocate %d SMP blocks: %d\n", 211 n, ret); 212 return ret; 213 } 214 215 nblks += n; 216 } 217 218 set_fifo_thresholds(smp, pipe, nblks); 219 220 return 0; 221} 222 223/* Release SMP blocks for all clients of the pipe */ 224void mdp5_smp_release(struct mdp5_smp *smp, enum mdp5_pipe pipe) 225{ 226 int i, nblks; 227 228 for (i = 0, nblks = 0; i < pipe2nclients(pipe); i++) 229 smp_request_block(smp, pipe2client(pipe, i), 0); 230 set_fifo_thresholds(smp, pipe, 0); 231} 232 233static void update_smp_state(struct mdp5_smp *smp, 234 u32 cid, mdp5_smp_state_t *assigned) 235{ 236 struct mdp5_kms *mdp5_kms = get_kms(smp); 237 int cnt = smp->blk_cnt; 238 u32 blk, val; 239 240 for_each_set_bit(blk, *assigned, cnt) { 241 int idx = blk / 3; 242 int fld = blk % 3; 243 244 val = mdp5_read(mdp5_kms, REG_MDP5_MDP_SMP_ALLOC_W_REG(0, idx)); 245 246 switch (fld) { 247 case 0: 248 val &= ~MDP5_MDP_SMP_ALLOC_W_REG_CLIENT0__MASK; 249 val |= MDP5_MDP_SMP_ALLOC_W_REG_CLIENT0(cid); 250 break; 251 case 1: 252 val &= ~MDP5_MDP_SMP_ALLOC_W_REG_CLIENT1__MASK; 253 val |= MDP5_MDP_SMP_ALLOC_W_REG_CLIENT1(cid); 254 break; 255 case 2: 256 val &= ~MDP5_MDP_SMP_ALLOC_W_REG_CLIENT2__MASK; 257 val |= MDP5_MDP_SMP_ALLOC_W_REG_CLIENT2(cid); 258 break; 259 } 260 261 mdp5_write(mdp5_kms, REG_MDP5_MDP_SMP_ALLOC_W_REG(0, idx), val); 262 mdp5_write(mdp5_kms, REG_MDP5_MDP_SMP_ALLOC_R_REG(0, idx), val); 263 } 264} 265 266/* step #2: configure hw for union(pending, inuse): */ 267void mdp5_smp_configure(struct mdp5_smp *smp, enum mdp5_pipe pipe) 268{ 269 int cnt = smp->blk_cnt; 270 mdp5_smp_state_t assigned; 271 int i; 272 273 for (i = 0; i < pipe2nclients(pipe); i++) { 274 u32 cid = pipe2client(pipe, i); 275 struct mdp5_client_smp_state *ps = &smp->client_state[cid]; 276 277 bitmap_or(assigned, ps->inuse, ps->pending, cnt); 278 update_smp_state(smp, cid, &assigned); 279 } 280} 281 282/* step #3: after vblank, copy pending -> inuse: */ 283void mdp5_smp_commit(struct mdp5_smp *smp, enum mdp5_pipe pipe) 284{ 285 int cnt = smp->blk_cnt; 286 mdp5_smp_state_t released; 287 int i; 288 289 for (i = 0; i < pipe2nclients(pipe); i++) { 290 u32 cid = pipe2client(pipe, i); 291 struct mdp5_client_smp_state *ps = &smp->client_state[cid]; 292 293 /* 294 * Figure out if there are any blocks we where previously 295 * using, which can be released and made available to other 296 * clients: 297 */ 298 if (bitmap_andnot(released, ps->inuse, ps->pending, cnt)) { 299 unsigned long flags; 300 301 spin_lock_irqsave(&smp->state_lock, flags); 302 /* clear released blocks: */ 303 bitmap_andnot(smp->state, smp->state, released, cnt); 304 spin_unlock_irqrestore(&smp->state_lock, flags); 305 306 update_smp_state(smp, CID_UNUSED, &released); 307 } 308 309 bitmap_copy(ps->inuse, ps->pending, cnt); 310 } 311} 312 313void mdp5_smp_destroy(struct mdp5_smp *smp) 314{ 315 kfree(smp); 316} 317 318struct mdp5_smp *mdp5_smp_init(struct drm_device *dev, const struct mdp5_smp_block *cfg) 319{ 320 struct mdp5_smp *smp = NULL; 321 int ret; 322 323 smp = kzalloc(sizeof(*smp), GFP_KERNEL); 324 if (unlikely(!smp)) { 325 ret = -ENOMEM; 326 goto fail; 327 } 328 329 smp->dev = dev; 330 smp->blk_cnt = cfg->mmb_count; 331 smp->blk_size = cfg->mmb_size; 332 333 /* statically tied MMBs cannot be re-allocated: */ 334 bitmap_copy(smp->state, cfg->reserved_state, smp->blk_cnt); 335 spin_lock_init(&smp->state_lock); 336 337 return smp; 338fail: 339 if (smp) 340 mdp5_smp_destroy(smp); 341 342 return ERR_PTR(ret); 343} 344