drivers/usb/host/xhci-mtk-sch.c

   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 SS_BW_BOUNDARY  51000
  17 /* table 5-5. High-speed Isoc Transaction Limits in usb_20 spec */
  18 #define HS_BW_BOUNDARY  6144
  19 /* usb2 spec section11.18.1: at most 188 FS bytes per microframe */
  20 #define FS_PAYLOAD_MAX 188
  21
  22 /* mtk scheduler bitmasks */
  23 #define EP_BPKTS(p)     ((p) & 0x3f)
  24 #define EP_BCSCOUNT(p)  (((p) & 0x7) << 8)
  25 #define EP_BBM(p)       ((p) << 11)
  26 #define EP_BOFFSET(p)   ((p) & 0x3fff)
  27 #define EP_BREPEAT(p)   (((p) & 0x7fff) << 16)
  28
  29 static int is_fs_or_ls(enum usb_device_speed speed)
  30 {
  31         return speed == USB_SPEED_FULL || speed == USB_SPEED_LOW;
  32 }
  33
  34 /*
  35 * get the index of bandwidth domains array which @ep belongs to.
  36 *
  37 * the bandwidth domain array is saved to @sch_array of struct xhci_hcd_mtk,
  38 * each HS root port is treated as a single bandwidth domain,
  39 * but each SS root port is treated as two bandwidth domains, one for IN eps,
  40 * one for OUT eps.
  41 * @real_port value is defined as follow according to xHCI spec:
  42 * 1 for SSport0, ..., N+1 for SSportN, N+2 for HSport0, N+3 for HSport1, etc
  43 * so the bandwidth domain array is organized as follow for simplification:
  44 * SSport0-OUT, SSport0-IN, ..., SSportX-OUT, SSportX-IN, HSport0, ..., HSportY
  45 */
  46 static int get_bw_index(struct xhci_hcd *xhci, struct usb_device *udev,
  47         struct usb_host_endpoint *ep)
  48 {
  49         struct xhci_virt_device *virt_dev;
  50         int bw_index;
  51
  52         virt_dev = xhci->devs[udev->slot_id];
  53
  54         if (udev->speed == USB_SPEED_SUPER) {
  55                 if (usb_endpoint_dir_out(&ep->desc))
  56                         bw_index = (virt_dev->real_port - 1) * 2;
  57                 else
  58                         bw_index = (virt_dev->real_port - 1) * 2 + 1;
  59         } else {
  60                 /* add one more for each SS port */
  61                 bw_index = virt_dev->real_port + xhci->usb3_rhub.num_ports - 1;
  62         }
  63
  64         return bw_index;
  65 }
  66
  67 static void setup_sch_info(struct usb_device *udev,
  68                 struct xhci_ep_ctx *ep_ctx, struct mu3h_sch_ep_info *sch_ep)
  69 {
  70         u32 ep_type;
  71         u32 ep_interval;
  72         u32 max_packet_size;
  73         u32 max_burst;
  74         u32 mult;
  75         u32 esit_pkts;
  76
  77         ep_type = CTX_TO_EP_TYPE(le32_to_cpu(ep_ctx->ep_info2));
  78         ep_interval = CTX_TO_EP_INTERVAL(le32_to_cpu(ep_ctx->ep_info));
  79         max_packet_size = MAX_PACKET_DECODED(le32_to_cpu(ep_ctx->ep_info2));
  80         max_burst = CTX_TO_MAX_BURST(le32_to_cpu(ep_ctx->ep_info2));
  81         mult = CTX_TO_EP_MULT(le32_to_cpu(ep_ctx->ep_info));
  82
  83         sch_ep->esit = 1 << ep_interval;
  84         sch_ep->offset = 0;
  85         sch_ep->burst_mode = 0;
  86
  87         if (udev->speed == USB_SPEED_HIGH) {
  88                 sch_ep->cs_count = 0;
  89
  90                 /*
  91                  * usb_20 spec section5.9
  92                  * a single microframe is enough for HS synchromous endpoints
  93                  * in a interval
  94                  */
  95                 sch_ep->num_budget_microframes = 1;
  96                 sch_ep->repeat = 0;
  97
  98                 /*
  99                  * xHCI spec section6.2.3.4
 100                  * @max_burst is the number of additional transactions
 101                  * opportunities per microframe
 102                  */
 103                 sch_ep->pkts = max_burst + 1;
 104                 sch_ep->bw_cost_per_microframe = max_packet_size * sch_ep->pkts;
 105         } else if (udev->speed == USB_SPEED_SUPER) {
 106                 /* usb3_r1 spec section4.4.7 & 4.4.8 */
 107                 sch_ep->cs_count = 0;
 108                 esit_pkts = (mult + 1) * (max_burst + 1);
 109                 if (ep_type == INT_IN_EP || ep_type == INT_OUT_EP) {
 110                         sch_ep->pkts = esit_pkts;
 111                         sch_ep->num_budget_microframes = 1;
 112                         sch_ep->repeat = 0;
 113                 }
 114
 115                 if (ep_type == ISOC_IN_EP || ep_type == ISOC_OUT_EP) {
 116                         if (esit_pkts <= sch_ep->esit)
 117                                 sch_ep->pkts = 1;
 118                         else
 119                                 sch_ep->pkts = roundup_pow_of_two(esit_pkts)
 120                                         / sch_ep->esit;
 121
 122                         sch_ep->num_budget_microframes =
 123                                 DIV_ROUND_UP(esit_pkts, sch_ep->pkts);
 124
 125                         if (sch_ep->num_budget_microframes > 1)
 126                                 sch_ep->repeat = 1;
 127                         else
 128                                 sch_ep->repeat = 0;
 129                 }
 130                 sch_ep->bw_cost_per_microframe = max_packet_size * sch_ep->pkts;
 131         } else if (is_fs_or_ls(udev->speed)) {
 132
 133                 /*
 134                  * usb_20 spec section11.18.4
 135                  * assume worst cases
 136                  */
 137                 sch_ep->repeat = 0;
 138                 sch_ep->pkts = 1; /* at most one packet for each microframe */
 139                 if (ep_type == INT_IN_EP || ep_type == INT_OUT_EP) {
 140                         sch_ep->cs_count = 3; /* at most need 3 CS*/
 141                         /* one for SS and one for budgeted transaction */
 142                         sch_ep->num_budget_microframes = sch_ep->cs_count + 2;
 143                         sch_ep->bw_cost_per_microframe = max_packet_size;
 144                 }
 145                 if (ep_type == ISOC_OUT_EP) {
 146
 147                         /*
 148                          * the best case FS budget assumes that 188 FS bytes
 149                          * occur in each microframe
 150                          */
 151                         sch_ep->num_budget_microframes = DIV_ROUND_UP(
 152                                 max_packet_size, FS_PAYLOAD_MAX);
 153                         sch_ep->bw_cost_per_microframe = FS_PAYLOAD_MAX;
 154                         sch_ep->cs_count = sch_ep->num_budget_microframes;
 155                 }
 156                 if (ep_type == ISOC_IN_EP) {
 157                         /* at most need additional two CS. */
 158                         sch_ep->cs_count = DIV_ROUND_UP(
 159                                 max_packet_size, FS_PAYLOAD_MAX) + 2;
 160                         sch_ep->num_budget_microframes = sch_ep->cs_count + 2;
 161                         sch_ep->bw_cost_per_microframe = FS_PAYLOAD_MAX;
 162                 }
 163         }
 164 }
 165
 166 /* Get maximum bandwidth when we schedule at offset slot. */
 167 static u32 get_max_bw(struct mu3h_sch_bw_info *sch_bw,
 168         struct mu3h_sch_ep_info *sch_ep, u32 offset)
 169 {
 170         u32 num_esit;
 171         u32 max_bw = 0;
 172         int i;
 173         int j;
 174
 175         num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
 176         for (i = 0; i < num_esit; i++) {
 177                 u32 base = offset + i * sch_ep->esit;
 178
 179                 for (j = 0; j < sch_ep->num_budget_microframes; j++) {
 180                         if (sch_bw->bus_bw[base + j] > max_bw)
 181                                 max_bw = sch_bw->bus_bw[base + j];
 182                 }
 183         }
 184         return max_bw;
 185 }
 186
 187 static void update_bus_bw(struct mu3h_sch_bw_info *sch_bw,
 188         struct mu3h_sch_ep_info *sch_ep, int bw_cost)
 189 {
 190         u32 num_esit;
 191         u32 base;
 192         int i;
 193         int j;
 194
 195         num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
 196         for (i = 0; i < num_esit; i++) {
 197                 base = sch_ep->offset + i * sch_ep->esit;
 198                 for (j = 0; j < sch_ep->num_budget_microframes; j++)
 199                         sch_bw->bus_bw[base + j] += bw_cost;
 200         }
 201 }
 202
 203 static int check_sch_bw(struct usb_device *udev,
 204         struct mu3h_sch_bw_info *sch_bw, struct mu3h_sch_ep_info *sch_ep)
 205 {
 206         u32 offset;
 207         u32 esit;
 208         u32 num_budget_microframes;
 209         u32 min_bw;
 210         u32 min_index;
 211         u32 worst_bw;
 212         u32 bw_boundary;
 213
 214         if (sch_ep->esit > XHCI_MTK_MAX_ESIT)
 215                 sch_ep->esit = XHCI_MTK_MAX_ESIT;
 216
 217         esit = sch_ep->esit;
 218         num_budget_microframes = sch_ep->num_budget_microframes;
 219
 220         /*
 221          * Search through all possible schedule microframes.
 222          * and find a microframe where its worst bandwidth is minimum.
 223          */
 224         min_bw = ~0;
 225         min_index = 0;
 226         for (offset = 0; offset < esit; offset++) {
 227                 if ((offset + num_budget_microframes) > sch_ep->esit)
 228                         break;
 229
 230                 /*
 231                  * usb_20 spec section11.18:
 232                  * must never schedule Start-Split in Y6
 233                  */
 234                 if (is_fs_or_ls(udev->speed) && (offset % 8 == 6))
 235                         continue;
 236
 237                 worst_bw = get_max_bw(sch_bw, sch_ep, offset);
 238                 if (min_bw > worst_bw) {
 239                         min_bw = worst_bw;
 240                         min_index = offset;
 241                 }
 242                 if (min_bw == 0)
 243                         break;
 244         }
 245         sch_ep->offset = min_index;
 246
 247         bw_boundary = (udev->speed == USB_SPEED_SUPER)
 248                                 ? SS_BW_BOUNDARY : HS_BW_BOUNDARY;
 249
 250         /* check bandwidth */
 251         if (min_bw + sch_ep->bw_cost_per_microframe > bw_boundary)
 252                 return -ERANGE;
 253
 254         /* update bus bandwidth info */
 255         update_bus_bw(sch_bw, sch_ep, sch_ep->bw_cost_per_microframe);
 256
 257         return 0;
 258 }
 259
 260 static bool need_bw_sch(struct usb_host_endpoint *ep,
 261         enum usb_device_speed speed, int has_tt)
 262 {
 263         /* only for periodic endpoints */
 264         if (usb_endpoint_xfer_control(&ep->desc)
 265                 || usb_endpoint_xfer_bulk(&ep->desc))
 266                 return false;
 267
 268         /*
 269          * for LS & FS periodic endpoints which its device is not behind
 270          * a TT are also ignored, root-hub will schedule them directly,
 271          * but need set @bpkts field of endpoint context to 1.
 272          */
 273         if (is_fs_or_ls(speed) && !has_tt)
 274                 return false;
 275
 276         return true;
 277 }
 278
 279 int xhci_mtk_sch_init(struct xhci_hcd_mtk *mtk)
 280 {
 281         struct xhci_hcd *xhci = hcd_to_xhci(mtk->hcd);
 282         struct mu3h_sch_bw_info *sch_array;
 283         int num_usb_bus;
 284         int i;
 285
 286         /* ss IN and OUT are separated */
 287         num_usb_bus = xhci->usb3_rhub.num_ports * 2 + xhci->usb2_rhub.num_ports;
 288
 289         sch_array = kcalloc(num_usb_bus, sizeof(*sch_array), GFP_KERNEL);
 290         if (sch_array == NULL)
 291                 return -ENOMEM;
 292
 293         for (i = 0; i < num_usb_bus; i++)
 294                 INIT_LIST_HEAD(&sch_array[i].bw_ep_list);
 295
 296         mtk->sch_array = sch_array;
 297
 298         return 0;
 299 }
 300 EXPORT_SYMBOL_GPL(xhci_mtk_sch_init);
 301
 302 void xhci_mtk_sch_exit(struct xhci_hcd_mtk *mtk)
 303 {
 304         kfree(mtk->sch_array);
 305 }
 306 EXPORT_SYMBOL_GPL(xhci_mtk_sch_exit);
 307
 308 int xhci_mtk_add_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
 309                 struct usb_host_endpoint *ep)
 310 {
 311         struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
 312         struct xhci_hcd *xhci;
 313         struct xhci_ep_ctx *ep_ctx;
 314         struct xhci_slot_ctx *slot_ctx;
 315         struct xhci_virt_device *virt_dev;
 316         struct mu3h_sch_bw_info *sch_bw;
 317         struct mu3h_sch_ep_info *sch_ep;
 318         struct mu3h_sch_bw_info *sch_array;
 319         unsigned int ep_index;
 320         int bw_index;
 321         int ret = 0;
 322
 323         xhci = hcd_to_xhci(hcd);
 324         virt_dev = xhci->devs[udev->slot_id];
 325         ep_index = xhci_get_endpoint_index(&ep->desc);
 326         slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->in_ctx);
 327         ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, ep_index);
 328         sch_array = mtk->sch_array;
 329
 330         xhci_dbg(xhci, "%s() type:%d, speed:%d, mpkt:%d, dir:%d, ep:%p\n",
 331                 __func__, usb_endpoint_type(&ep->desc), udev->speed,
 332                 usb_endpoint_maxp(&ep->desc),
 333                 usb_endpoint_dir_in(&ep->desc), ep);
 334
 335         if (!need_bw_sch(ep, udev->speed, slot_ctx->tt_info & TT_SLOT)) {
 336                 /*
 337                  * set @bpkts to 1 if it is LS or FS periodic endpoint, and its
 338                  * device does not connected through an external HS hub
 339                  */
 340                 if (usb_endpoint_xfer_int(&ep->desc)
 341                         || usb_endpoint_xfer_isoc(&ep->desc))
 342                         ep_ctx->reserved[0] |= cpu_to_le32(EP_BPKTS(1));
 343
 344                 return 0;
 345         }
 346
 347         bw_index = get_bw_index(xhci, udev, ep);
 348         sch_bw = &sch_array[bw_index];
 349
 350         sch_ep = kzalloc(sizeof(struct mu3h_sch_ep_info), GFP_NOIO);
 351         if (!sch_ep)
 352                 return -ENOMEM;
 353
 354         setup_sch_info(udev, ep_ctx, sch_ep);
 355
 356         ret = check_sch_bw(udev, sch_bw, sch_ep);
 357         if (ret) {
 358                 xhci_err(xhci, "Not enough bandwidth!\n");
 359                 kfree(sch_ep);
 360                 return -ENOSPC;
 361         }
 362
 363         list_add_tail(&sch_ep->endpoint, &sch_bw->bw_ep_list);
 364         sch_ep->ep = ep;
 365
 366         ep_ctx->reserved[0] |= cpu_to_le32(EP_BPKTS(sch_ep->pkts)
 367                 | EP_BCSCOUNT(sch_ep->cs_count) | EP_BBM(sch_ep->burst_mode));
 368         ep_ctx->reserved[1] |= cpu_to_le32(EP_BOFFSET(sch_ep->offset)
 369                 | EP_BREPEAT(sch_ep->repeat));
 370
 371         xhci_dbg(xhci, " PKTS:%x, CSCOUNT:%x, BM:%x, OFFSET:%x, REPEAT:%x\n",
 372                         sch_ep->pkts, sch_ep->cs_count, sch_ep->burst_mode,
 373                         sch_ep->offset, sch_ep->repeat);
 374
 375         return 0;
 376 }
 377 EXPORT_SYMBOL_GPL(xhci_mtk_add_ep_quirk);
 378
 379 void xhci_mtk_drop_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
 380                 struct usb_host_endpoint *ep)
 381 {
 382         struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
 383         struct xhci_hcd *xhci;
 384         struct xhci_slot_ctx *slot_ctx;
 385         struct xhci_virt_device *virt_dev;
 386         struct mu3h_sch_bw_info *sch_array;
 387         struct mu3h_sch_bw_info *sch_bw;
 388         struct mu3h_sch_ep_info *sch_ep;
 389         int bw_index;
 390
 391         xhci = hcd_to_xhci(hcd);
 392         virt_dev = xhci->devs[udev->slot_id];
 393         slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->in_ctx);
 394         sch_array = mtk->sch_array;
 395
 396         xhci_dbg(xhci, "%s() type:%d, speed:%d, mpks:%d, dir:%d, ep:%p\n",
 397                 __func__, usb_endpoint_type(&ep->desc), udev->speed,
 398                 usb_endpoint_maxp(&ep->desc),
 399                 usb_endpoint_dir_in(&ep->desc), ep);
 400
 401         if (!need_bw_sch(ep, udev->speed, slot_ctx->tt_info & TT_SLOT))
 402                 return;
 403
 404         bw_index = get_bw_index(xhci, udev, ep);
 405         sch_bw = &sch_array[bw_index];
 406
 407         list_for_each_entry(sch_ep, &sch_bw->bw_ep_list, endpoint) {
 408                 if (sch_ep->ep == ep) {
 409                         update_bus_bw(sch_bw, sch_ep,
 410                                 -sch_ep->bw_cost_per_microframe);
 411                         list_del(&sch_ep->endpoint);
 412                         kfree(sch_ep);
 413                         break;
 414                 }
 415         }
 416 }
 417 EXPORT_SYMBOL_GPL(xhci_mtk_drop_ep_quirk);