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 (sch_ep->esit == 1)
 117                                 sch_ep->pkts = esit_pkts;
 118                         else if (esit_pkts <= sch_ep->esit)
 119                                 sch_ep->pkts = 1;
 120                         else
 121                                 sch_ep->pkts = roundup_pow_of_two(esit_pkts)
 122                                         / sch_ep->esit;
 123
 124                         sch_ep->num_budget_microframes =
 125                                 DIV_ROUND_UP(esit_pkts, sch_ep->pkts);
 126
 127                         if (sch_ep->num_budget_microframes > 1)
 128                                 sch_ep->repeat = 1;
 129                         else
 130                                 sch_ep->repeat = 0;
 131                 }
 132                 sch_ep->bw_cost_per_microframe = max_packet_size * sch_ep->pkts;
 133         } else if (is_fs_or_ls(udev->speed)) {
 134
 135                 /*
 136                  * usb_20 spec section11.18.4
 137                  * assume worst cases
 138                  */
 139                 sch_ep->repeat = 0;
 140                 sch_ep->pkts = 1; /* at most one packet for each microframe */
 141                 if (ep_type == INT_IN_EP || ep_type == INT_OUT_EP) {
 142                         sch_ep->cs_count = 3; /* at most need 3 CS*/
 143                         /* one for SS and one for budgeted transaction */
 144                         sch_ep->num_budget_microframes = sch_ep->cs_count + 2;
 145                         sch_ep->bw_cost_per_microframe = max_packet_size;
 146                 }
 147                 if (ep_type == ISOC_OUT_EP) {
 148
 149                         /*
 150                          * the best case FS budget assumes that 188 FS bytes
 151                          * occur in each microframe
 152                          */
 153                         sch_ep->num_budget_microframes = DIV_ROUND_UP(
 154                                 max_packet_size, FS_PAYLOAD_MAX);
 155                         sch_ep->bw_cost_per_microframe = FS_PAYLOAD_MAX;
 156                         sch_ep->cs_count = sch_ep->num_budget_microframes;
 157                 }
 158                 if (ep_type == ISOC_IN_EP) {
 159                         /* at most need additional two CS. */
 160                         sch_ep->cs_count = DIV_ROUND_UP(
 161                                 max_packet_size, FS_PAYLOAD_MAX) + 2;
 162                         sch_ep->num_budget_microframes = sch_ep->cs_count + 2;
 163                         sch_ep->bw_cost_per_microframe = FS_PAYLOAD_MAX;
 164                 }
 165         }
 166 }
 167
 168 /* Get maximum bandwidth when we schedule at offset slot. */
 169 static u32 get_max_bw(struct mu3h_sch_bw_info *sch_bw,
 170         struct mu3h_sch_ep_info *sch_ep, u32 offset)
 171 {
 172         u32 num_esit;
 173         u32 max_bw = 0;
 174         int i;
 175         int j;
 176
 177         num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
 178         for (i = 0; i < num_esit; i++) {
 179                 u32 base = offset + i * sch_ep->esit;
 180
 181                 for (j = 0; j < sch_ep->num_budget_microframes; j++) {
 182                         if (sch_bw->bus_bw[base + j] > max_bw)
 183                                 max_bw = sch_bw->bus_bw[base + j];
 184                 }
 185         }
 186         return max_bw;
 187 }
 188
 189 static void update_bus_bw(struct mu3h_sch_bw_info *sch_bw,
 190         struct mu3h_sch_ep_info *sch_ep, int bw_cost)
 191 {
 192         u32 num_esit;
 193         u32 base;
 194         int i;
 195         int j;
 196
 197         num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
 198         for (i = 0; i < num_esit; i++) {
 199                 base = sch_ep->offset + i * sch_ep->esit;
 200                 for (j = 0; j < sch_ep->num_budget_microframes; j++)
 201                         sch_bw->bus_bw[base + j] += bw_cost;
 202         }
 203 }
 204
 205 static int check_sch_bw(struct usb_device *udev,
 206         struct mu3h_sch_bw_info *sch_bw, struct mu3h_sch_ep_info *sch_ep)
 207 {
 208         u32 offset;
 209         u32 esit;
 210         u32 num_budget_microframes;
 211         u32 min_bw;
 212         u32 min_index;
 213         u32 worst_bw;
 214         u32 bw_boundary;
 215
 216         if (sch_ep->esit > XHCI_MTK_MAX_ESIT)
 217                 sch_ep->esit = XHCI_MTK_MAX_ESIT;
 218
 219         esit = sch_ep->esit;
 220         num_budget_microframes = sch_ep->num_budget_microframes;
 221
 222         /*
 223          * Search through all possible schedule microframes.
 224          * and find a microframe where its worst bandwidth is minimum.
 225          */
 226         min_bw = ~0;
 227         min_index = 0;
 228         for (offset = 0; offset < esit; offset++) {
 229                 if ((offset + num_budget_microframes) > sch_ep->esit)
 230                         break;
 231
 232                 /*
 233                  * usb_20 spec section11.18:
 234                  * must never schedule Start-Split in Y6
 235                  */
 236                 if (is_fs_or_ls(udev->speed) && (offset % 8 == 6))
 237                         continue;
 238
 239                 worst_bw = get_max_bw(sch_bw, sch_ep, offset);
 240                 if (min_bw > worst_bw) {
 241                         min_bw = worst_bw;
 242                         min_index = offset;
 243                 }
 244                 if (min_bw == 0)
 245                         break;
 246         }
 247         sch_ep->offset = min_index;
 248
 249         bw_boundary = (udev->speed == USB_SPEED_SUPER)
 250                                 ? SS_BW_BOUNDARY : HS_BW_BOUNDARY;
 251
 252         /* check bandwidth */
 253         if (min_bw + sch_ep->bw_cost_per_microframe > bw_boundary)
 254                 return -ERANGE;
 255
 256         /* update bus bandwidth info */
 257         update_bus_bw(sch_bw, sch_ep, sch_ep->bw_cost_per_microframe);
 258
 259         return 0;
 260 }
 261
 262 static bool need_bw_sch(struct usb_host_endpoint *ep,
 263         enum usb_device_speed speed, int has_tt)
 264 {
 265         /* only for periodic endpoints */
 266         if (usb_endpoint_xfer_control(&ep->desc)
 267                 || usb_endpoint_xfer_bulk(&ep->desc))
 268                 return false;
 269
 270         /*
 271          * for LS & FS periodic endpoints which its device is not behind
 272          * a TT are also ignored, root-hub will schedule them directly,
 273          * but need set @bpkts field of endpoint context to 1.
 274          */
 275         if (is_fs_or_ls(speed) && !has_tt)
 276                 return false;
 277
 278         return true;
 279 }
 280
 281 int xhci_mtk_sch_init(struct xhci_hcd_mtk *mtk)
 282 {
 283         struct xhci_hcd *xhci = hcd_to_xhci(mtk->hcd);
 284         struct mu3h_sch_bw_info *sch_array;
 285         int num_usb_bus;
 286         int i;
 287
 288         /* ss IN and OUT are separated */
 289         num_usb_bus = xhci->usb3_rhub.num_ports * 2 + xhci->usb2_rhub.num_ports;
 290
 291         sch_array = kcalloc(num_usb_bus, sizeof(*sch_array), GFP_KERNEL);
 292         if (sch_array == NULL)
 293                 return -ENOMEM;
 294
 295         for (i = 0; i < num_usb_bus; i++)
 296                 INIT_LIST_HEAD(&sch_array[i].bw_ep_list);
 297
 298         mtk->sch_array = sch_array;
 299
 300         return 0;
 301 }
 302 EXPORT_SYMBOL_GPL(xhci_mtk_sch_init);
 303
 304 void xhci_mtk_sch_exit(struct xhci_hcd_mtk *mtk)
 305 {
 306         kfree(mtk->sch_array);
 307 }
 308 EXPORT_SYMBOL_GPL(xhci_mtk_sch_exit);
 309
 310 int xhci_mtk_add_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
 311                 struct usb_host_endpoint *ep)
 312 {
 313         struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
 314         struct xhci_hcd *xhci;
 315         struct xhci_ep_ctx *ep_ctx;
 316         struct xhci_slot_ctx *slot_ctx;
 317         struct xhci_virt_device *virt_dev;
 318         struct mu3h_sch_bw_info *sch_bw;
 319         struct mu3h_sch_ep_info *sch_ep;
 320         struct mu3h_sch_bw_info *sch_array;
 321         unsigned int ep_index;
 322         int bw_index;
 323         int ret = 0;
 324
 325         xhci = hcd_to_xhci(hcd);
 326         virt_dev = xhci->devs[udev->slot_id];
 327         ep_index = xhci_get_endpoint_index(&ep->desc);
 328         slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->in_ctx);
 329         ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, ep_index);
 330         sch_array = mtk->sch_array;
 331
 332         xhci_dbg(xhci, "%s() type:%d, speed:%d, mpkt:%d, dir:%d, ep:%p\n",
 333                 __func__, usb_endpoint_type(&ep->desc), udev->speed,
 334                 usb_endpoint_maxp(&ep->desc),
 335                 usb_endpoint_dir_in(&ep->desc), ep);
 336
 337         if (!need_bw_sch(ep, udev->speed, slot_ctx->tt_info & TT_SLOT)) {
 338                 /*
 339                  * set @bpkts to 1 if it is LS or FS periodic endpoint, and its
 340                  * device does not connected through an external HS hub
 341                  */
 342                 if (usb_endpoint_xfer_int(&ep->desc)
 343                         || usb_endpoint_xfer_isoc(&ep->desc))
 344                         ep_ctx->reserved[0] |= cpu_to_le32(EP_BPKTS(1));
 345
 346                 return 0;
 347         }
 348
 349         bw_index = get_bw_index(xhci, udev, ep);
 350         sch_bw = &sch_array[bw_index];
 351
 352         sch_ep = kzalloc(sizeof(struct mu3h_sch_ep_info), GFP_NOIO);
 353         if (!sch_ep)
 354                 return -ENOMEM;
 355
 356         setup_sch_info(udev, ep_ctx, sch_ep);
 357
 358         ret = check_sch_bw(udev, sch_bw, sch_ep);
 359         if (ret) {
 360                 xhci_err(xhci, "Not enough bandwidth!\n");
 361                 kfree(sch_ep);
 362                 return -ENOSPC;
 363         }
 364
 365         list_add_tail(&sch_ep->endpoint, &sch_bw->bw_ep_list);
 366         sch_ep->ep = ep;
 367
 368         ep_ctx->reserved[0] |= cpu_to_le32(EP_BPKTS(sch_ep->pkts)
 369                 | EP_BCSCOUNT(sch_ep->cs_count) | EP_BBM(sch_ep->burst_mode));
 370         ep_ctx->reserved[1] |= cpu_to_le32(EP_BOFFSET(sch_ep->offset)
 371                 | EP_BREPEAT(sch_ep->repeat));
 372
 373         xhci_dbg(xhci, " PKTS:%x, CSCOUNT:%x, BM:%x, OFFSET:%x, REPEAT:%x\n",
 374                         sch_ep->pkts, sch_ep->cs_count, sch_ep->burst_mode,
 375                         sch_ep->offset, sch_ep->repeat);
 376
 377         return 0;
 378 }
 379 EXPORT_SYMBOL_GPL(xhci_mtk_add_ep_quirk);
 380
 381 void xhci_mtk_drop_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
 382                 struct usb_host_endpoint *ep)
 383 {
 384         struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
 385         struct xhci_hcd *xhci;
 386         struct xhci_slot_ctx *slot_ctx;
 387         struct xhci_virt_device *virt_dev;
 388         struct mu3h_sch_bw_info *sch_array;
 389         struct mu3h_sch_bw_info *sch_bw;
 390         struct mu3h_sch_ep_info *sch_ep;
 391         int bw_index;
 392
 393         xhci = hcd_to_xhci(hcd);
 394         virt_dev = xhci->devs[udev->slot_id];
 395         slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->in_ctx);
 396         sch_array = mtk->sch_array;
 397
 398         xhci_dbg(xhci, "%s() type:%d, speed:%d, mpks:%d, dir:%d, ep:%p\n",
 399                 __func__, usb_endpoint_type(&ep->desc), udev->speed,
 400                 usb_endpoint_maxp(&ep->desc),
 401                 usb_endpoint_dir_in(&ep->desc), ep);
 402
 403         if (!need_bw_sch(ep, udev->speed, slot_ctx->tt_info & TT_SLOT))
 404                 return;
 405
 406         bw_index = get_bw_index(xhci, udev, ep);
 407         sch_bw = &sch_array[bw_index];
 408
 409         list_for_each_entry(sch_ep, &sch_bw->bw_ep_list, endpoint) {
 410                 if (sch_ep->ep == ep) {
 411                         update_bus_bw(sch_bw, sch_ep,
 412                                 -sch_ep->bw_cost_per_microframe);
 413                         list_del(&sch_ep->endpoint);
 414                         kfree(sch_ep);
 415                         break;
 416                 }
 417         }
 418 }
 419 EXPORT_SYMBOL_GPL(xhci_mtk_drop_ep_quirk);