linux/drivers/usb/host/xhci-mtk-sch.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2015 MediaTek Inc.
   4 * Author:
   5 *  Zhigang.Wei <zhigang.wei@mediatek.com>
   6 *  Chunfeng.Yun <chunfeng.yun@mediatek.com>
   7 */
   8
   9#include <linux/kernel.h>
  10#include <linux/module.h>
  11#include <linux/slab.h>
  12
  13#include "xhci.h"
  14#include "xhci-mtk.h"
  15
  16#define SSP_BW_BOUNDARY 130000
  17#define SS_BW_BOUNDARY  51000
  18/* table 5-5. High-speed Isoc Transaction Limits in usb_20 spec */
  19#define HS_BW_BOUNDARY  6144
  20/* usb2 spec section11.18.1: at most 188 FS bytes per microframe */
  21#define FS_PAYLOAD_MAX 188
  22/*
  23 * max number of microframes for split transfer,
  24 * for fs isoc in : 1 ss + 1 idle + 7 cs
  25 */
  26#define TT_MICROFRAMES_MAX 9
  27
  28#define DBG_BUF_EN      64
  29
  30/* schedule error type */
  31#define ESCH_SS_Y6              1001
  32#define ESCH_SS_OVERLAP         1002
  33#define ESCH_CS_OVERFLOW        1003
  34#define ESCH_BW_OVERFLOW        1004
  35#define ESCH_FIXME              1005
  36
  37/* mtk scheduler bitmasks */
  38#define EP_BPKTS(p)     ((p) & 0x7f)
  39#define EP_BCSCOUNT(p)  (((p) & 0x7) << 8)
  40#define EP_BBM(p)       ((p) << 11)
  41#define EP_BOFFSET(p)   ((p) & 0x3fff)
  42#define EP_BREPEAT(p)   (((p) & 0x7fff) << 16)
  43
  44static char *sch_error_string(int err_num)
  45{
  46        switch (err_num) {
  47        case ESCH_SS_Y6:
  48                return "Can't schedule Start-Split in Y6";
  49        case ESCH_SS_OVERLAP:
  50                return "Can't find a suitable Start-Split location";
  51        case ESCH_CS_OVERFLOW:
  52                return "The last Complete-Split is greater than 7";
  53        case ESCH_BW_OVERFLOW:
  54                return "Bandwidth exceeds the maximum limit";
  55        case ESCH_FIXME:
  56                return "FIXME, to be resolved";
  57        default:
  58                return "Unknown";
  59        }
  60}
  61
  62static int is_fs_or_ls(enum usb_device_speed speed)
  63{
  64        return speed == USB_SPEED_FULL || speed == USB_SPEED_LOW;
  65}
  66
  67static const char *
  68decode_ep(struct usb_host_endpoint *ep, enum usb_device_speed speed)
  69{
  70        static char buf[DBG_BUF_EN];
  71        struct usb_endpoint_descriptor *epd = &ep->desc;
  72        unsigned int interval;
  73        const char *unit;
  74
  75        interval = usb_decode_interval(epd, speed);
  76        if (interval % 1000) {
  77                unit = "us";
  78        } else {
  79                unit = "ms";
  80                interval /= 1000;
  81        }
  82
  83        snprintf(buf, DBG_BUF_EN, "%s ep%d%s %s, mpkt:%d, interval:%d/%d%s\n",
  84                 usb_speed_string(speed), usb_endpoint_num(epd),
  85                 usb_endpoint_dir_in(epd) ? "in" : "out",
  86                 usb_ep_type_string(usb_endpoint_type(epd)),
  87                 usb_endpoint_maxp(epd), epd->bInterval, interval, unit);
  88
  89        return buf;
  90}
  91
  92static u32 get_bw_boundary(enum usb_device_speed speed)
  93{
  94        u32 boundary;
  95
  96        switch (speed) {
  97        case USB_SPEED_SUPER_PLUS:
  98                boundary = SSP_BW_BOUNDARY;
  99                break;
 100        case USB_SPEED_SUPER:
 101                boundary = SS_BW_BOUNDARY;
 102                break;
 103        default:
 104                boundary = HS_BW_BOUNDARY;
 105                break;
 106        }
 107
 108        return boundary;
 109}
 110
 111/*
 112* get the bandwidth domain which @ep belongs to.
 113*
 114* the bandwidth domain array is saved to @sch_array of struct xhci_hcd_mtk,
 115* each HS root port is treated as a single bandwidth domain,
 116* but each SS root port is treated as two bandwidth domains, one for IN eps,
 117* one for OUT eps.
 118* @real_port value is defined as follow according to xHCI spec:
 119* 1 for SSport0, ..., N+1 for SSportN, N+2 for HSport0, N+3 for HSport1, etc
 120* so the bandwidth domain array is organized as follow for simplification:
 121* SSport0-OUT, SSport0-IN, ..., SSportX-OUT, SSportX-IN, HSport0, ..., HSportY
 122*/
 123static struct mu3h_sch_bw_info *
 124get_bw_info(struct xhci_hcd_mtk *mtk, struct usb_device *udev,
 125            struct usb_host_endpoint *ep)
 126{
 127        struct xhci_hcd *xhci = hcd_to_xhci(mtk->hcd);
 128        struct xhci_virt_device *virt_dev;
 129        int bw_index;
 130
 131        virt_dev = xhci->devs[udev->slot_id];
 132
 133        if (udev->speed >= USB_SPEED_SUPER) {
 134                if (usb_endpoint_dir_out(&ep->desc))
 135                        bw_index = (virt_dev->real_port - 1) * 2;
 136                else
 137                        bw_index = (virt_dev->real_port - 1) * 2 + 1;
 138        } else {
 139                /* add one more for each SS port */
 140                bw_index = virt_dev->real_port + xhci->usb3_rhub.num_ports - 1;
 141        }
 142
 143        return &mtk->sch_array[bw_index];
 144}
 145
 146static u32 get_esit(struct xhci_ep_ctx *ep_ctx)
 147{
 148        u32 esit;
 149
 150        esit = 1 << CTX_TO_EP_INTERVAL(le32_to_cpu(ep_ctx->ep_info));
 151        if (esit > XHCI_MTK_MAX_ESIT)
 152                esit = XHCI_MTK_MAX_ESIT;
 153
 154        return esit;
 155}
 156
 157static struct mu3h_sch_tt *find_tt(struct usb_device *udev)
 158{
 159        struct usb_tt *utt = udev->tt;
 160        struct mu3h_sch_tt *tt, **tt_index, **ptt;
 161        bool allocated_index = false;
 162
 163        if (!utt)
 164                return NULL;    /* Not below a TT */
 165
 166        /*
 167         * Find/create our data structure.
 168         * For hubs with a single TT, we get it directly.
 169         * For hubs with multiple TTs, there's an extra level of pointers.
 170         */
 171        tt_index = NULL;
 172        if (utt->multi) {
 173                tt_index = utt->hcpriv;
 174                if (!tt_index) {        /* Create the index array */
 175                        tt_index = kcalloc(utt->hub->maxchild,
 176                                        sizeof(*tt_index), GFP_KERNEL);
 177                        if (!tt_index)
 178                                return ERR_PTR(-ENOMEM);
 179                        utt->hcpriv = tt_index;
 180                        allocated_index = true;
 181                }
 182                ptt = &tt_index[udev->ttport - 1];
 183        } else {
 184                ptt = (struct mu3h_sch_tt **) &utt->hcpriv;
 185        }
 186
 187        tt = *ptt;
 188        if (!tt) {      /* Create the mu3h_sch_tt */
 189                tt = kzalloc(sizeof(*tt), GFP_KERNEL);
 190                if (!tt) {
 191                        if (allocated_index) {
 192                                utt->hcpriv = NULL;
 193                                kfree(tt_index);
 194                        }
 195                        return ERR_PTR(-ENOMEM);
 196                }
 197                INIT_LIST_HEAD(&tt->ep_list);
 198                *ptt = tt;
 199        }
 200
 201        return tt;
 202}
 203
 204/* Release the TT above udev, if it's not in use */
 205static void drop_tt(struct usb_device *udev)
 206{
 207        struct usb_tt *utt = udev->tt;
 208        struct mu3h_sch_tt *tt, **tt_index, **ptt;
 209        int i, cnt;
 210
 211        if (!utt || !utt->hcpriv)
 212                return;         /* Not below a TT, or never allocated */
 213
 214        cnt = 0;
 215        if (utt->multi) {
 216                tt_index = utt->hcpriv;
 217                ptt = &tt_index[udev->ttport - 1];
 218                /*  How many entries are left in tt_index? */
 219                for (i = 0; i < utt->hub->maxchild; ++i)
 220                        cnt += !!tt_index[i];
 221        } else {
 222                tt_index = NULL;
 223                ptt = (struct mu3h_sch_tt **)&utt->hcpriv;
 224        }
 225
 226        tt = *ptt;
 227        if (!tt || !list_empty(&tt->ep_list))
 228                return;         /* never allocated , or still in use*/
 229
 230        *ptt = NULL;
 231        kfree(tt);
 232
 233        if (cnt == 1) {
 234                utt->hcpriv = NULL;
 235                kfree(tt_index);
 236        }
 237}
 238
 239static struct mu3h_sch_ep_info *create_sch_ep(struct usb_device *udev,
 240        struct usb_host_endpoint *ep, struct xhci_ep_ctx *ep_ctx)
 241{
 242        struct mu3h_sch_ep_info *sch_ep;
 243        struct mu3h_sch_tt *tt = NULL;
 244        u32 len_bw_budget_table;
 245        size_t mem_size;
 246
 247        if (is_fs_or_ls(udev->speed))
 248                len_bw_budget_table = TT_MICROFRAMES_MAX;
 249        else if ((udev->speed >= USB_SPEED_SUPER)
 250                        && usb_endpoint_xfer_isoc(&ep->desc))
 251                len_bw_budget_table = get_esit(ep_ctx);
 252        else
 253                len_bw_budget_table = 1;
 254
 255        mem_size = sizeof(struct mu3h_sch_ep_info) +
 256                        len_bw_budget_table * sizeof(u32);
 257        sch_ep = kzalloc(mem_size, GFP_KERNEL);
 258        if (!sch_ep)
 259                return ERR_PTR(-ENOMEM);
 260
 261        if (is_fs_or_ls(udev->speed)) {
 262                tt = find_tt(udev);
 263                if (IS_ERR(tt)) {
 264                        kfree(sch_ep);
 265                        return ERR_PTR(-ENOMEM);
 266                }
 267        }
 268
 269        sch_ep->sch_tt = tt;
 270        sch_ep->ep = ep;
 271        sch_ep->speed = udev->speed;
 272        INIT_LIST_HEAD(&sch_ep->endpoint);
 273        INIT_LIST_HEAD(&sch_ep->tt_endpoint);
 274
 275        return sch_ep;
 276}
 277
 278static void setup_sch_info(struct xhci_ep_ctx *ep_ctx,
 279                           struct mu3h_sch_ep_info *sch_ep)
 280{
 281        u32 ep_type;
 282        u32 maxpkt;
 283        u32 max_burst;
 284        u32 mult;
 285        u32 esit_pkts;
 286        u32 max_esit_payload;
 287        u32 *bwb_table = sch_ep->bw_budget_table;
 288        int i;
 289
 290        ep_type = CTX_TO_EP_TYPE(le32_to_cpu(ep_ctx->ep_info2));
 291        maxpkt = MAX_PACKET_DECODED(le32_to_cpu(ep_ctx->ep_info2));
 292        max_burst = CTX_TO_MAX_BURST(le32_to_cpu(ep_ctx->ep_info2));
 293        mult = CTX_TO_EP_MULT(le32_to_cpu(ep_ctx->ep_info));
 294        max_esit_payload =
 295                (CTX_TO_MAX_ESIT_PAYLOAD_HI(
 296                        le32_to_cpu(ep_ctx->ep_info)) << 16) |
 297                 CTX_TO_MAX_ESIT_PAYLOAD(le32_to_cpu(ep_ctx->tx_info));
 298
 299        sch_ep->esit = get_esit(ep_ctx);
 300        sch_ep->ep_type = ep_type;
 301        sch_ep->maxpkt = maxpkt;
 302        sch_ep->offset = 0;
 303        sch_ep->burst_mode = 0;
 304        sch_ep->repeat = 0;
 305
 306        if (sch_ep->speed == USB_SPEED_HIGH) {
 307                sch_ep->cs_count = 0;
 308
 309                /*
 310                 * usb_20 spec section5.9
 311                 * a single microframe is enough for HS synchromous endpoints
 312                 * in a interval
 313                 */
 314                sch_ep->num_budget_microframes = 1;
 315
 316                /*
 317                 * xHCI spec section6.2.3.4
 318                 * @max_burst is the number of additional transactions
 319                 * opportunities per microframe
 320                 */
 321                sch_ep->pkts = max_burst + 1;
 322                sch_ep->bw_cost_per_microframe = maxpkt * sch_ep->pkts;
 323                bwb_table[0] = sch_ep->bw_cost_per_microframe;
 324        } else if (sch_ep->speed >= USB_SPEED_SUPER) {
 325                /* usb3_r1 spec section4.4.7 & 4.4.8 */
 326                sch_ep->cs_count = 0;
 327                sch_ep->burst_mode = 1;
 328                /*
 329                 * some device's (d)wBytesPerInterval is set as 0,
 330                 * then max_esit_payload is 0, so evaluate esit_pkts from
 331                 * mult and burst
 332                 */
 333                esit_pkts = DIV_ROUND_UP(max_esit_payload, maxpkt);
 334                if (esit_pkts == 0)
 335                        esit_pkts = (mult + 1) * (max_burst + 1);
 336
 337                if (ep_type == INT_IN_EP || ep_type == INT_OUT_EP) {
 338                        sch_ep->pkts = esit_pkts;
 339                        sch_ep->num_budget_microframes = 1;
 340                        bwb_table[0] = maxpkt * sch_ep->pkts;
 341                }
 342
 343                if (ep_type == ISOC_IN_EP || ep_type == ISOC_OUT_EP) {
 344
 345                        if (sch_ep->esit == 1)
 346                                sch_ep->pkts = esit_pkts;
 347                        else if (esit_pkts <= sch_ep->esit)
 348                                sch_ep->pkts = 1;
 349                        else
 350                                sch_ep->pkts = roundup_pow_of_two(esit_pkts)
 351                                        / sch_ep->esit;
 352
 353                        sch_ep->num_budget_microframes =
 354                                DIV_ROUND_UP(esit_pkts, sch_ep->pkts);
 355
 356                        sch_ep->repeat = !!(sch_ep->num_budget_microframes > 1);
 357                        sch_ep->bw_cost_per_microframe = maxpkt * sch_ep->pkts;
 358
 359                        for (i = 0; i < sch_ep->num_budget_microframes - 1; i++)
 360                                bwb_table[i] = sch_ep->bw_cost_per_microframe;
 361
 362                        /* last one <= bw_cost_per_microframe */
 363                        bwb_table[i] = maxpkt * esit_pkts
 364                                       - i * sch_ep->bw_cost_per_microframe;
 365                }
 366        } else if (is_fs_or_ls(sch_ep->speed)) {
 367                sch_ep->pkts = 1; /* at most one packet for each microframe */
 368
 369                /*
 370                 * num_budget_microframes and cs_count will be updated when
 371                 * check TT for INT_OUT_EP, ISOC/INT_IN_EP type
 372                 */
 373                sch_ep->cs_count = DIV_ROUND_UP(maxpkt, FS_PAYLOAD_MAX);
 374                sch_ep->num_budget_microframes = sch_ep->cs_count;
 375                sch_ep->bw_cost_per_microframe =
 376                        (maxpkt < FS_PAYLOAD_MAX) ? maxpkt : FS_PAYLOAD_MAX;
 377
 378                /* init budget table */
 379                if (ep_type == ISOC_OUT_EP) {
 380                        for (i = 0; i < sch_ep->num_budget_microframes; i++)
 381                                bwb_table[i] =  sch_ep->bw_cost_per_microframe;
 382                } else if (ep_type == INT_OUT_EP) {
 383                        /* only first one consumes bandwidth, others as zero */
 384                        bwb_table[0] = sch_ep->bw_cost_per_microframe;
 385                } else { /* INT_IN_EP or ISOC_IN_EP */
 386                        bwb_table[0] = 0; /* start split */
 387                        bwb_table[1] = 0; /* idle */
 388                        /*
 389                         * due to cs_count will be updated according to cs
 390                         * position, assign all remainder budget array
 391                         * elements as @bw_cost_per_microframe, but only first
 392                         * @num_budget_microframes elements will be used later
 393                         */
 394                        for (i = 2; i < TT_MICROFRAMES_MAX; i++)
 395                                bwb_table[i] =  sch_ep->bw_cost_per_microframe;
 396                }
 397        }
 398}
 399
 400/* Get maximum bandwidth when we schedule at offset slot. */
 401static u32 get_max_bw(struct mu3h_sch_bw_info *sch_bw,
 402        struct mu3h_sch_ep_info *sch_ep, u32 offset)
 403{
 404        u32 num_esit;
 405        u32 max_bw = 0;
 406        u32 bw;
 407        int i;
 408        int j;
 409
 410        num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
 411        for (i = 0; i < num_esit; i++) {
 412                u32 base = offset + i * sch_ep->esit;
 413
 414                for (j = 0; j < sch_ep->num_budget_microframes; j++) {
 415                        bw = sch_bw->bus_bw[base + j] +
 416                                        sch_ep->bw_budget_table[j];
 417                        if (bw > max_bw)
 418                                max_bw = bw;
 419                }
 420        }
 421        return max_bw;
 422}
 423
 424static void update_bus_bw(struct mu3h_sch_bw_info *sch_bw,
 425        struct mu3h_sch_ep_info *sch_ep, bool used)
 426{
 427        u32 num_esit;
 428        u32 base;
 429        int i;
 430        int j;
 431
 432        num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
 433        for (i = 0; i < num_esit; i++) {
 434                base = sch_ep->offset + i * sch_ep->esit;
 435                for (j = 0; j < sch_ep->num_budget_microframes; j++) {
 436                        if (used)
 437                                sch_bw->bus_bw[base + j] +=
 438                                        sch_ep->bw_budget_table[j];
 439                        else
 440                                sch_bw->bus_bw[base + j] -=
 441                                        sch_ep->bw_budget_table[j];
 442                }
 443        }
 444}
 445
 446static int check_fs_bus_bw(struct mu3h_sch_ep_info *sch_ep, int offset)
 447{
 448        struct mu3h_sch_tt *tt = sch_ep->sch_tt;
 449        u32 num_esit, tmp;
 450        int base;
 451        int i, j;
 452
 453        num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
 454        for (i = 0; i < num_esit; i++) {
 455                base = offset + i * sch_ep->esit;
 456
 457                /*
 458                 * Compared with hs bus, no matter what ep type,
 459                 * the hub will always delay one uframe to send data
 460                 */
 461                for (j = 0; j < sch_ep->cs_count; j++) {
 462                        tmp = tt->fs_bus_bw[base + j] + sch_ep->bw_cost_per_microframe;
 463                        if (tmp > FS_PAYLOAD_MAX)
 464                                return -ESCH_BW_OVERFLOW;
 465                }
 466        }
 467
 468        return 0;
 469}
 470
 471static int check_sch_tt(struct mu3h_sch_ep_info *sch_ep, u32 offset)
 472{
 473        u32 extra_cs_count;
 474        u32 start_ss, last_ss;
 475        u32 start_cs, last_cs;
 476
 477        if (!sch_ep->sch_tt)
 478                return 0;
 479
 480        start_ss = offset % 8;
 481
 482        if (sch_ep->ep_type == ISOC_OUT_EP) {
 483                last_ss = start_ss + sch_ep->cs_count - 1;
 484
 485                /*
 486                 * usb_20 spec section11.18:
 487                 * must never schedule Start-Split in Y6
 488                 */
 489                if (!(start_ss == 7 || last_ss < 6))
 490                        return -ESCH_SS_Y6;
 491
 492        } else {
 493                u32 cs_count = DIV_ROUND_UP(sch_ep->maxpkt, FS_PAYLOAD_MAX);
 494
 495                /*
 496                 * usb_20 spec section11.18:
 497                 * must never schedule Start-Split in Y6
 498                 */
 499                if (start_ss == 6)
 500                        return -ESCH_SS_Y6;
 501
 502                /* one uframe for ss + one uframe for idle */
 503                start_cs = (start_ss + 2) % 8;
 504                last_cs = start_cs + cs_count - 1;
 505
 506                if (last_cs > 7)
 507                        return -ESCH_CS_OVERFLOW;
 508
 509                if (sch_ep->ep_type == ISOC_IN_EP)
 510                        extra_cs_count = (last_cs == 7) ? 1 : 2;
 511                else /*  ep_type : INTR IN / INTR OUT */
 512                        extra_cs_count = 1;
 513
 514                cs_count += extra_cs_count;
 515                if (cs_count > 7)
 516                        cs_count = 7; /* HW limit */
 517
 518                sch_ep->cs_count = cs_count;
 519                /* one for ss, the other for idle */
 520                sch_ep->num_budget_microframes = cs_count + 2;
 521
 522                /*
 523                 * if interval=1, maxp >752, num_budge_micoframe is larger
 524                 * than sch_ep->esit, will overstep boundary
 525                 */
 526                if (sch_ep->num_budget_microframes > sch_ep->esit)
 527                        sch_ep->num_budget_microframes = sch_ep->esit;
 528        }
 529
 530        return check_fs_bus_bw(sch_ep, offset);
 531}
 532
 533static void update_sch_tt(struct mu3h_sch_ep_info *sch_ep, bool used)
 534{
 535        struct mu3h_sch_tt *tt = sch_ep->sch_tt;
 536        u32 base, num_esit;
 537        int bw_updated;
 538        int i, j;
 539
 540        num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
 541
 542        if (used)
 543                bw_updated = sch_ep->bw_cost_per_microframe;
 544        else
 545                bw_updated = -sch_ep->bw_cost_per_microframe;
 546
 547        for (i = 0; i < num_esit; i++) {
 548                base = sch_ep->offset + i * sch_ep->esit;
 549
 550                for (j = 0; j < sch_ep->cs_count; j++)
 551                        tt->fs_bus_bw[base + j] += bw_updated;
 552        }
 553
 554        if (used)
 555                list_add_tail(&sch_ep->tt_endpoint, &tt->ep_list);
 556        else
 557                list_del(&sch_ep->tt_endpoint);
 558}
 559
 560static int load_ep_bw(struct mu3h_sch_bw_info *sch_bw,
 561                      struct mu3h_sch_ep_info *sch_ep, bool loaded)
 562{
 563        if (sch_ep->sch_tt)
 564                update_sch_tt(sch_ep, loaded);
 565
 566        /* update bus bandwidth info */
 567        update_bus_bw(sch_bw, sch_ep, loaded);
 568        sch_ep->allocated = loaded;
 569
 570        return 0;
 571}
 572
 573static u32 get_esit_boundary(struct mu3h_sch_ep_info *sch_ep)
 574{
 575        u32 boundary = sch_ep->esit;
 576
 577        if (sch_ep->sch_tt) { /* LS/FS with TT */
 578                /* tune for CS */
 579                if (sch_ep->ep_type != ISOC_OUT_EP)
 580                        boundary++;
 581                else if (boundary > 1) /* normally esit >= 8 for FS/LS */
 582                        boundary--;
 583        }
 584
 585        return boundary;
 586}
 587
 588static int check_sch_bw(struct mu3h_sch_bw_info *sch_bw,
 589                        struct mu3h_sch_ep_info *sch_ep)
 590{
 591        const u32 esit_boundary = get_esit_boundary(sch_ep);
 592        const u32 bw_boundary = get_bw_boundary(sch_ep->speed);
 593        u32 offset;
 594        u32 worst_bw;
 595        u32 min_bw = ~0;
 596        int min_index = -1;
 597        int ret = 0;
 598
 599        /*
 600         * Search through all possible schedule microframes.
 601         * and find a microframe where its worst bandwidth is minimum.
 602         */
 603        for (offset = 0; offset < sch_ep->esit; offset++) {
 604                ret = check_sch_tt(sch_ep, offset);
 605                if (ret)
 606                        continue;
 607
 608                if ((offset + sch_ep->num_budget_microframes) > esit_boundary)
 609                        break;
 610
 611                worst_bw = get_max_bw(sch_bw, sch_ep, offset);
 612                if (worst_bw > bw_boundary)
 613                        continue;
 614
 615                if (min_bw > worst_bw) {
 616                        min_bw = worst_bw;
 617                        min_index = offset;
 618                }
 619
 620                /* use first-fit for LS/FS */
 621                if (sch_ep->sch_tt && min_index >= 0)
 622                        break;
 623
 624                if (min_bw == 0)
 625                        break;
 626        }
 627
 628        if (min_index < 0)
 629                return ret ? ret : -ESCH_BW_OVERFLOW;
 630
 631        sch_ep->offset = min_index;
 632
 633        return load_ep_bw(sch_bw, sch_ep, true);
 634}
 635
 636static void destroy_sch_ep(struct usb_device *udev,
 637        struct mu3h_sch_bw_info *sch_bw, struct mu3h_sch_ep_info *sch_ep)
 638{
 639        /* only release ep bw check passed by check_sch_bw() */
 640        if (sch_ep->allocated)
 641                load_ep_bw(sch_bw, sch_ep, false);
 642
 643        if (sch_ep->sch_tt)
 644                drop_tt(udev);
 645
 646        list_del(&sch_ep->endpoint);
 647        kfree(sch_ep);
 648}
 649
 650static bool need_bw_sch(struct usb_host_endpoint *ep,
 651        enum usb_device_speed speed, int has_tt)
 652{
 653        /* only for periodic endpoints */
 654        if (usb_endpoint_xfer_control(&ep->desc)
 655                || usb_endpoint_xfer_bulk(&ep->desc))
 656                return false;
 657
 658        /*
 659         * for LS & FS periodic endpoints which its device is not behind
 660         * a TT are also ignored, root-hub will schedule them directly,
 661         * but need set @bpkts field of endpoint context to 1.
 662         */
 663        if (is_fs_or_ls(speed) && !has_tt)
 664                return false;
 665
 666        /* skip endpoint with zero maxpkt */
 667        if (usb_endpoint_maxp(&ep->desc) == 0)
 668                return false;
 669
 670        return true;
 671}
 672
 673int xhci_mtk_sch_init(struct xhci_hcd_mtk *mtk)
 674{
 675        struct xhci_hcd *xhci = hcd_to_xhci(mtk->hcd);
 676        struct mu3h_sch_bw_info *sch_array;
 677        int num_usb_bus;
 678        int i;
 679
 680        /* ss IN and OUT are separated */
 681        num_usb_bus = xhci->usb3_rhub.num_ports * 2 + xhci->usb2_rhub.num_ports;
 682
 683        sch_array = kcalloc(num_usb_bus, sizeof(*sch_array), GFP_KERNEL);
 684        if (sch_array == NULL)
 685                return -ENOMEM;
 686
 687        for (i = 0; i < num_usb_bus; i++)
 688                INIT_LIST_HEAD(&sch_array[i].bw_ep_list);
 689
 690        mtk->sch_array = sch_array;
 691
 692        INIT_LIST_HEAD(&mtk->bw_ep_chk_list);
 693
 694        return 0;
 695}
 696
 697void xhci_mtk_sch_exit(struct xhci_hcd_mtk *mtk)
 698{
 699        kfree(mtk->sch_array);
 700}
 701
 702static int add_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
 703                        struct usb_host_endpoint *ep)
 704{
 705        struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
 706        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
 707        struct xhci_ep_ctx *ep_ctx;
 708        struct xhci_virt_device *virt_dev;
 709        struct mu3h_sch_ep_info *sch_ep;
 710        unsigned int ep_index;
 711
 712        virt_dev = xhci->devs[udev->slot_id];
 713        ep_index = xhci_get_endpoint_index(&ep->desc);
 714        ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, ep_index);
 715
 716        xhci_dbg(xhci, "%s %s\n", __func__, decode_ep(ep, udev->speed));
 717
 718        if (!need_bw_sch(ep, udev->speed, !!virt_dev->tt_info)) {
 719                /*
 720                 * set @bpkts to 1 if it is LS or FS periodic endpoint, and its
 721                 * device does not connected through an external HS hub
 722                 */
 723                if (usb_endpoint_xfer_int(&ep->desc)
 724                        || usb_endpoint_xfer_isoc(&ep->desc))
 725                        ep_ctx->reserved[0] = cpu_to_le32(EP_BPKTS(1));
 726
 727                return 0;
 728        }
 729
 730        sch_ep = create_sch_ep(udev, ep, ep_ctx);
 731        if (IS_ERR_OR_NULL(sch_ep))
 732                return -ENOMEM;
 733
 734        setup_sch_info(ep_ctx, sch_ep);
 735
 736        list_add_tail(&sch_ep->endpoint, &mtk->bw_ep_chk_list);
 737
 738        return 0;
 739}
 740
 741static void drop_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
 742                          struct usb_host_endpoint *ep)
 743{
 744        struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
 745        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
 746        struct xhci_virt_device *virt_dev;
 747        struct mu3h_sch_bw_info *sch_bw;
 748        struct mu3h_sch_ep_info *sch_ep, *tmp;
 749
 750        virt_dev = xhci->devs[udev->slot_id];
 751
 752        xhci_dbg(xhci, "%s %s\n", __func__, decode_ep(ep, udev->speed));
 753
 754        if (!need_bw_sch(ep, udev->speed, !!virt_dev->tt_info))
 755                return;
 756
 757        sch_bw = get_bw_info(mtk, udev, ep);
 758
 759        list_for_each_entry_safe(sch_ep, tmp, &sch_bw->bw_ep_list, endpoint) {
 760                if (sch_ep->ep == ep) {
 761                        destroy_sch_ep(udev, sch_bw, sch_ep);
 762                        break;
 763                }
 764        }
 765}
 766
 767int xhci_mtk_check_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
 768{
 769        struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
 770        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
 771        struct xhci_virt_device *virt_dev = xhci->devs[udev->slot_id];
 772        struct mu3h_sch_bw_info *sch_bw;
 773        struct mu3h_sch_ep_info *sch_ep, *tmp;
 774        int ret;
 775
 776        xhci_dbg(xhci, "%s() udev %s\n", __func__, dev_name(&udev->dev));
 777
 778        list_for_each_entry(sch_ep, &mtk->bw_ep_chk_list, endpoint) {
 779                sch_bw = get_bw_info(mtk, udev, sch_ep->ep);
 780
 781                ret = check_sch_bw(sch_bw, sch_ep);
 782                if (ret) {
 783                        xhci_err(xhci, "Not enough bandwidth! (%s)\n",
 784                                 sch_error_string(-ret));
 785                        return -ENOSPC;
 786                }
 787        }
 788
 789        list_for_each_entry_safe(sch_ep, tmp, &mtk->bw_ep_chk_list, endpoint) {
 790                struct xhci_ep_ctx *ep_ctx;
 791                struct usb_host_endpoint *ep = sch_ep->ep;
 792                unsigned int ep_index = xhci_get_endpoint_index(&ep->desc);
 793
 794                sch_bw = get_bw_info(mtk, udev, ep);
 795                list_move_tail(&sch_ep->endpoint, &sch_bw->bw_ep_list);
 796
 797                ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, ep_index);
 798                ep_ctx->reserved[0] = cpu_to_le32(EP_BPKTS(sch_ep->pkts)
 799                        | EP_BCSCOUNT(sch_ep->cs_count)
 800                        | EP_BBM(sch_ep->burst_mode));
 801                ep_ctx->reserved[1] = cpu_to_le32(EP_BOFFSET(sch_ep->offset)
 802                        | EP_BREPEAT(sch_ep->repeat));
 803
 804                xhci_dbg(xhci, " PKTS:%x, CSCOUNT:%x, BM:%x, OFFSET:%x, REPEAT:%x\n",
 805                        sch_ep->pkts, sch_ep->cs_count, sch_ep->burst_mode,
 806                        sch_ep->offset, sch_ep->repeat);
 807        }
 808
 809        return xhci_check_bandwidth(hcd, udev);
 810}
 811
 812void xhci_mtk_reset_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
 813{
 814        struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
 815        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
 816        struct mu3h_sch_bw_info *sch_bw;
 817        struct mu3h_sch_ep_info *sch_ep, *tmp;
 818
 819        xhci_dbg(xhci, "%s() udev %s\n", __func__, dev_name(&udev->dev));
 820
 821        list_for_each_entry_safe(sch_ep, tmp, &mtk->bw_ep_chk_list, endpoint) {
 822                sch_bw = get_bw_info(mtk, udev, sch_ep->ep);
 823                destroy_sch_ep(udev, sch_bw, sch_ep);
 824        }
 825
 826        xhci_reset_bandwidth(hcd, udev);
 827}
 828
 829int xhci_mtk_add_ep(struct usb_hcd *hcd, struct usb_device *udev,
 830                    struct usb_host_endpoint *ep)
 831{
 832        int ret;
 833
 834        ret = xhci_add_endpoint(hcd, udev, ep);
 835        if (ret)
 836                return ret;
 837
 838        if (ep->hcpriv)
 839                ret = add_ep_quirk(hcd, udev, ep);
 840
 841        return ret;
 842}
 843
 844int xhci_mtk_drop_ep(struct usb_hcd *hcd, struct usb_device *udev,
 845                     struct usb_host_endpoint *ep)
 846{
 847        int ret;
 848
 849        ret = xhci_drop_endpoint(hcd, udev, ep);
 850        if (ret)
 851                return ret;
 852
 853        if (ep->hcpriv)
 854                drop_ep_quirk(hcd, udev, ep);
 855
 856        return 0;
 857}
 858