drivers/usb/gadget/udc/bdc/bdc_core.c

   1 /*
   2  * bdc_core.c - BRCM BDC USB3.0 device controller core operations
   3  *
   4  * Copyright (C) 2014 Broadcom Corporation
   5  *
   6  * Author: Ashwini Pahuja
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the
  10  * Free Software Foundation; either version 2 of the License, or (at your
  11  * option) any later version.
  12  *
  13  */
  14 #include <linux/module.h>
  15 #include <linux/kernel.h>
  16 #include <linux/slab.h>
  17 #include <linux/spinlock.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/ioport.h>
  21 #include <linux/io.h>
  22 #include <linux/list.h>
  23 #include <linux/delay.h>
  24 #include <linux/dma-mapping.h>
  25 #include <linux/dmapool.h>
  26 #include <linux/of.h>
  27 #include <linux/moduleparam.h>
  28 #include <linux/usb/ch9.h>
  29 #include <linux/usb/gadget.h>
  30
  31 #include "bdc.h"
  32 #include "bdc_dbg.h"
  33
  34 /* Poll till controller status is not OIP */
  35 static int poll_oip(struct bdc *bdc, int usec)
  36 {
  37         u32 status;
  38         /* Poll till STS!= OIP */
  39         while (usec) {
  40                 status = bdc_readl(bdc->regs, BDC_BDCSC);
  41                 if (BDC_CSTS(status) != BDC_OIP) {
  42                         dev_dbg(bdc->dev,
  43                                 "poll_oip complete status=%d",
  44                                 BDC_CSTS(status));
  45                         return 0;
  46                 }
  47                 udelay(10);
  48                 usec -= 10;
  49         }
  50         dev_err(bdc->dev, "Err: operation timedout BDCSC: 0x%08x\n", status);
  51
  52         return -ETIMEDOUT;
  53 }
  54
  55 /* Stop the BDC controller */
  56 int bdc_stop(struct bdc *bdc)
  57 {
  58         int ret;
  59         u32 temp;
  60
  61         dev_dbg(bdc->dev, "%s ()\n\n", __func__);
  62         temp = bdc_readl(bdc->regs, BDC_BDCSC);
  63         /* Check if BDC is already halted */
  64         if (BDC_CSTS(temp) == BDC_HLT) {
  65                 dev_vdbg(bdc->dev, "BDC already halted\n");
  66                 return 0;
  67         }
  68         temp &= ~BDC_COP_MASK;
  69         temp |= BDC_COS|BDC_COP_STP;
  70         bdc_writel(bdc->regs, BDC_BDCSC, temp);
  71
  72         ret = poll_oip(bdc, BDC_COP_TIMEOUT);
  73         if (ret)
  74                 dev_err(bdc->dev, "bdc stop operation failed");
  75
  76         return ret;
  77 }
  78
  79 /* Issue a reset to BDC controller */
  80 int bdc_reset(struct bdc *bdc)
  81 {
  82         u32 temp;
  83         int ret;
  84
  85         dev_dbg(bdc->dev, "%s ()\n", __func__);
  86         /* First halt the controller */
  87         ret = bdc_stop(bdc);
  88         if (ret)
  89                 return ret;
  90
  91         temp = bdc_readl(bdc->regs, BDC_BDCSC);
  92         temp &= ~BDC_COP_MASK;
  93         temp |= BDC_COS|BDC_COP_RST;
  94         bdc_writel(bdc->regs, BDC_BDCSC, temp);
  95         ret = poll_oip(bdc, BDC_COP_TIMEOUT);
  96         if (ret)
  97                 dev_err(bdc->dev, "bdc reset operation failed");
  98
  99         return ret;
 100 }
 101
 102 /* Run the BDC controller */
 103 int bdc_run(struct bdc *bdc)
 104 {
 105         u32 temp;
 106         int ret;
 107
 108         dev_dbg(bdc->dev, "%s ()\n", __func__);
 109         temp = bdc_readl(bdc->regs, BDC_BDCSC);
 110         /* if BDC is already in running state then do not do anything */
 111         if (BDC_CSTS(temp) == BDC_NOR) {
 112                 dev_warn(bdc->dev, "bdc is already in running state\n");
 113                 return 0;
 114         }
 115         temp &= ~BDC_COP_MASK;
 116         temp |= BDC_COP_RUN;
 117         temp |= BDC_COS;
 118         bdc_writel(bdc->regs, BDC_BDCSC, temp);
 119         ret = poll_oip(bdc, BDC_COP_TIMEOUT);
 120         if (ret) {
 121                 dev_err(bdc->dev, "bdc run operation failed:%d", ret);
 122                 return ret;
 123         }
 124         temp = bdc_readl(bdc->regs, BDC_BDCSC);
 125         if (BDC_CSTS(temp) != BDC_NOR) {
 126                 dev_err(bdc->dev, "bdc not in normal mode after RUN op :%d\n",
 127                                                                 BDC_CSTS(temp));
 128                 return -ESHUTDOWN;
 129         }
 130
 131         return 0;
 132 }
 133
 134 /*
 135  * Present the termination to the host, typically called from upstream port
 136  * event with Vbus present =1
 137  */
 138 void bdc_softconn(struct bdc *bdc)
 139 {
 140         u32 uspc;
 141
 142         uspc = bdc_readl(bdc->regs, BDC_USPC);
 143         uspc &= ~BDC_PST_MASK;
 144         uspc |= BDC_LINK_STATE_RX_DET;
 145         uspc |= BDC_SWS;
 146         dev_dbg(bdc->dev, "%s () uspc=%08x\n", __func__, uspc);
 147         bdc_writel(bdc->regs, BDC_USPC, uspc);
 148 }
 149
 150 /* Remove the termination */
 151 void bdc_softdisconn(struct bdc *bdc)
 152 {
 153         u32 uspc;
 154
 155         uspc = bdc_readl(bdc->regs, BDC_USPC);
 156         uspc |= BDC_SDC;
 157         uspc &= ~BDC_SCN;
 158         dev_dbg(bdc->dev, "%s () uspc=%x\n", __func__, uspc);
 159         bdc_writel(bdc->regs, BDC_USPC, uspc);
 160 }
 161
 162 /* Set up the scratchpad buffer array and scratchpad buffers, if needed. */
 163 static int scratchpad_setup(struct bdc *bdc)
 164 {
 165         int sp_buff_size;
 166         u32 low32;
 167         u32 upp32;
 168
 169         sp_buff_size = BDC_SPB(bdc_readl(bdc->regs, BDC_BDCCFG0));
 170         dev_dbg(bdc->dev, "%s() sp_buff_size=%d\n", __func__, sp_buff_size);
 171         if (!sp_buff_size) {
 172                 dev_dbg(bdc->dev, "Scratchpad buffer not needed\n");
 173                 return 0;
 174         }
 175         /* Refer to BDC spec, Table 4 for description of SPB */
 176         sp_buff_size = 1 << (sp_buff_size + 5);
 177         dev_dbg(bdc->dev, "Allocating %d bytes for scratchpad\n", sp_buff_size);
 178         bdc->scratchpad.buff  =  dma_zalloc_coherent(bdc->dev, sp_buff_size,
 179                                         &bdc->scratchpad.sp_dma, GFP_KERNEL);
 180
 181         if (!bdc->scratchpad.buff)
 182                 goto fail;
 183
 184         bdc->sp_buff_size = sp_buff_size;
 185         bdc->scratchpad.size = sp_buff_size;
 186         low32 = lower_32_bits(bdc->scratchpad.sp_dma);
 187         upp32 = upper_32_bits(bdc->scratchpad.sp_dma);
 188         cpu_to_le32s(&low32);
 189         cpu_to_le32s(&upp32);
 190         bdc_writel(bdc->regs, BDC_SPBBAL, low32);
 191         bdc_writel(bdc->regs, BDC_SPBBAH, upp32);
 192         return 0;
 193
 194 fail:
 195         bdc->scratchpad.buff = NULL;
 196
 197         return -ENOMEM;
 198 }
 199
 200 /* Allocate the status report ring */
 201 static int setup_srr(struct bdc *bdc, int interrupter)
 202 {
 203         dev_dbg(bdc->dev, "%s() NUM_SR_ENTRIES:%d\n", __func__, NUM_SR_ENTRIES);
 204         /* Reset the SRR */
 205         bdc_writel(bdc->regs, BDC_SRRINT(0), BDC_SRR_RWS | BDC_SRR_RST);
 206         bdc->srr.dqp_index = 0;
 207         /* allocate the status report descriptors */
 208         bdc->srr.sr_bds = dma_zalloc_coherent(
 209                                         bdc->dev,
 210                                         NUM_SR_ENTRIES * sizeof(struct bdc_bd),
 211                                         &bdc->srr.dma_addr,
 212                                         GFP_KERNEL);
 213         if (!bdc->srr.sr_bds)
 214                 return -ENOMEM;
 215
 216         return 0;
 217 }
 218
 219 /* Initialize the HW regs and internal data structures */
 220 static void bdc_mem_init(struct bdc *bdc, bool reinit)
 221 {
 222         u8 size = 0;
 223         u32 usb2_pm;
 224         u32 low32;
 225         u32 upp32;
 226         u32 temp;
 227
 228         dev_dbg(bdc->dev, "%s ()\n", __func__);
 229         bdc->ep0_state = WAIT_FOR_SETUP;
 230         bdc->dev_addr = 0;
 231         bdc->srr.eqp_index = 0;
 232         bdc->srr.dqp_index = 0;
 233         bdc->zlp_needed = false;
 234         bdc->delayed_status = false;
 235
 236         bdc_writel(bdc->regs, BDC_SPBBAL, bdc->scratchpad.sp_dma);
 237         /* Init the SRR */
 238         temp = BDC_SRR_RWS | BDC_SRR_RST;
 239         /* Reset the SRR */
 240         bdc_writel(bdc->regs, BDC_SRRINT(0), temp);
 241         dev_dbg(bdc->dev, "bdc->srr.sr_bds =%p\n", bdc->srr.sr_bds);
 242         temp = lower_32_bits(bdc->srr.dma_addr);
 243         size = fls(NUM_SR_ENTRIES) - 2;
 244         temp |= size;
 245         dev_dbg(bdc->dev, "SRRBAL[0]=%08x NUM_SR_ENTRIES:%d size:%d\n",
 246                                                 temp, NUM_SR_ENTRIES, size);
 247
 248         low32 = lower_32_bits(temp);
 249         upp32 = upper_32_bits(bdc->srr.dma_addr);
 250         cpu_to_le32s(&low32);
 251         cpu_to_le32s(&upp32);
 252
 253         /* Write the dma addresses into regs*/
 254         bdc_writel(bdc->regs, BDC_SRRBAL(0), low32);
 255         bdc_writel(bdc->regs, BDC_SRRBAH(0), upp32);
 256
 257         temp = bdc_readl(bdc->regs, BDC_SRRINT(0));
 258         temp |= BDC_SRR_IE;
 259         temp &= ~(BDC_SRR_RST | BDC_SRR_RWS);
 260         bdc_writel(bdc->regs, BDC_SRRINT(0), temp);
 261
 262         /* Set the Interrupt Coalescence ~500 usec */
 263         temp = bdc_readl(bdc->regs, BDC_INTCTLS(0));
 264         temp &= ~0xffff;
 265         temp |= INT_CLS;
 266         bdc_writel(bdc->regs, BDC_INTCTLS(0), temp);
 267
 268         usb2_pm = bdc_readl(bdc->regs, BDC_USPPM2);
 269         dev_dbg(bdc->dev, "usb2_pm=%08x", usb2_pm);
 270         /* Enable hardware LPM Enable */
 271         usb2_pm |= BDC_HLE;
 272         bdc_writel(bdc->regs, BDC_USPPM2, usb2_pm);
 273
 274         /* readback for debug */
 275         usb2_pm = bdc_readl(bdc->regs, BDC_USPPM2);
 276         dev_dbg(bdc->dev, "usb2_pm=%08x\n", usb2_pm);
 277
 278         /* Disable any unwanted SR's on SRR */
 279         temp = bdc_readl(bdc->regs, BDC_BDCSC);
 280         /* We don't want Microframe counter wrap SR */
 281         temp |= BDC_MASK_MCW;
 282         bdc_writel(bdc->regs, BDC_BDCSC, temp);
 283
 284         /*
 285          * In some error cases, driver has to reset the entire BDC controller
 286          * in that case reinit is passed as 1
 287          */
 288         if (reinit) {
 289                 /* Enable interrupts */
 290                 temp = bdc_readl(bdc->regs, BDC_BDCSC);
 291                 temp |= BDC_GIE;
 292                 bdc_writel(bdc->regs, BDC_BDCSC, temp);
 293                 /* Init scratchpad to 0 */
 294                 memset(bdc->scratchpad.buff, 0, bdc->sp_buff_size);
 295                 /* Initialize SRR to 0 */
 296                 memset(bdc->srr.sr_bds, 0,
 297                                         NUM_SR_ENTRIES * sizeof(struct bdc_bd));
 298         } else {
 299                 /* One time initiaization only */
 300                 /* Enable status report function pointers */
 301                 bdc->sr_handler[0] = bdc_sr_xsf;
 302                 bdc->sr_handler[1] = bdc_sr_uspc;
 303
 304                 /* EP0 status report function pointers */
 305                 bdc->sr_xsf_ep0[0] = bdc_xsf_ep0_setup_recv;
 306                 bdc->sr_xsf_ep0[1] = bdc_xsf_ep0_data_start;
 307                 bdc->sr_xsf_ep0[2] = bdc_xsf_ep0_status_start;
 308         }
 309 }
 310
 311 /* Free the dynamic memory */
 312 static void bdc_mem_free(struct bdc *bdc)
 313 {
 314         dev_dbg(bdc->dev, "%s\n", __func__);
 315         /* Free SRR */
 316         if (bdc->srr.sr_bds)
 317                 dma_free_coherent(bdc->dev,
 318                                         NUM_SR_ENTRIES * sizeof(struct bdc_bd),
 319                                         bdc->srr.sr_bds, bdc->srr.dma_addr);
 320
 321         /* Free scratchpad */
 322         if (bdc->scratchpad.buff)
 323                 dma_free_coherent(bdc->dev, bdc->sp_buff_size,
 324                                 bdc->scratchpad.buff, bdc->scratchpad.sp_dma);
 325
 326         /* Destroy the dma pools */
 327         dma_pool_destroy(bdc->bd_table_pool);
 328
 329         /* Free the bdc_ep array */
 330         kfree(bdc->bdc_ep_array);
 331
 332         bdc->srr.sr_bds = NULL;
 333         bdc->scratchpad.buff = NULL;
 334         bdc->bd_table_pool = NULL;
 335         bdc->bdc_ep_array = NULL;
 336 }
 337
 338 /*
 339  * bdc reinit gives a controller reset and reinitialize the registers,
 340  * called from disconnect/bus reset scenario's, to ensure proper HW cleanup
 341  */
 342 int bdc_reinit(struct bdc *bdc)
 343 {
 344         int ret;
 345
 346         dev_dbg(bdc->dev, "%s\n", __func__);
 347         ret = bdc_stop(bdc);
 348         if (ret)
 349                 goto out;
 350
 351         ret = bdc_reset(bdc);
 352         if (ret)
 353                 goto out;
 354
 355         /* the reinit flag is 1 */
 356         bdc_mem_init(bdc, true);
 357         ret = bdc_run(bdc);
 358 out:
 359         bdc->reinit = false;
 360
 361         return ret;
 362 }
 363
 364 /* Allocate all the dyanmic memory */
 365 static int bdc_mem_alloc(struct bdc *bdc)
 366 {
 367         u32 page_size;
 368         unsigned int num_ieps, num_oeps;
 369
 370         dev_dbg(bdc->dev,
 371                 "%s() NUM_BDS_PER_TABLE:%d\n", __func__,
 372                 NUM_BDS_PER_TABLE);
 373         page_size = BDC_PGS(bdc_readl(bdc->regs, BDC_BDCCFG0));
 374         /* page size is 2^pgs KB */
 375         page_size = 1 << page_size;
 376         /* KB */
 377         page_size <<= 10;
 378         dev_dbg(bdc->dev, "page_size=%d\n", page_size);
 379
 380         /* Create a pool of bd tables */
 381         bdc->bd_table_pool =
 382             dma_pool_create("BDC BD tables", bdc->dev, NUM_BDS_PER_TABLE * 16,
 383                                                                 16, page_size);
 384
 385         if (!bdc->bd_table_pool)
 386                 goto fail;
 387
 388         if (scratchpad_setup(bdc))
 389                 goto fail;
 390
 391         /* read from regs */
 392         num_ieps = NUM_NCS(bdc_readl(bdc->regs, BDC_FSCNIC));
 393         num_oeps = NUM_NCS(bdc_readl(bdc->regs, BDC_FSCNOC));
 394         /* +2: 1 for ep0 and the other is rsvd i.e. bdc_ep[0] is rsvd */
 395         bdc->num_eps = num_ieps + num_oeps + 2;
 396         dev_dbg(bdc->dev,
 397                 "ieps:%d eops:%d num_eps:%d\n",
 398                 num_ieps, num_oeps, bdc->num_eps);
 399         /* allocate array of ep pointers */
 400         bdc->bdc_ep_array = kcalloc(bdc->num_eps, sizeof(struct bdc_ep *),
 401                                                                 GFP_KERNEL);
 402         if (!bdc->bdc_ep_array)
 403                 goto fail;
 404
 405         dev_dbg(bdc->dev, "Allocating sr report0\n");
 406         if (setup_srr(bdc, 0))
 407                 goto fail;
 408
 409         return 0;
 410 fail:
 411         dev_warn(bdc->dev, "Couldn't initialize memory\n");
 412         bdc_mem_free(bdc);
 413
 414         return -ENOMEM;
 415 }
 416
 417 /* opposite to bdc_hw_init */
 418 static void bdc_hw_exit(struct bdc *bdc)
 419 {
 420         dev_dbg(bdc->dev, "%s ()\n", __func__);
 421         bdc_mem_free(bdc);
 422 }
 423
 424 /* Initialize the bdc HW and memory */
 425 static int bdc_hw_init(struct bdc *bdc)
 426 {
 427         int ret;
 428
 429         dev_dbg(bdc->dev, "%s ()\n", __func__);
 430         ret = bdc_reset(bdc);
 431         if (ret) {
 432                 dev_err(bdc->dev, "err resetting bdc abort bdc init%d\n", ret);
 433                 return ret;
 434         }
 435         ret = bdc_mem_alloc(bdc);
 436         if (ret) {
 437                 dev_err(bdc->dev, "Mem alloc failed, aborting\n");
 438                 return -ENOMEM;
 439         }
 440         bdc_mem_init(bdc, 0);
 441         bdc_dbg_regs(bdc);
 442         dev_dbg(bdc->dev, "HW Init done\n");
 443
 444         return 0;
 445 }
 446
 447 static int bdc_probe(struct platform_device *pdev)
 448 {
 449         struct bdc *bdc;
 450         struct resource *res;
 451         int ret = -ENOMEM;
 452         int irq;
 453         u32 temp;
 454         struct device *dev = &pdev->dev;
 455
 456         dev_dbg(dev, "%s()\n", __func__);
 457         bdc = devm_kzalloc(dev, sizeof(*bdc), GFP_KERNEL);
 458         if (!bdc)
 459                 return -ENOMEM;
 460
 461         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 462         bdc->regs = devm_ioremap_resource(dev, res);
 463         if (IS_ERR(bdc->regs)) {
 464                 dev_err(dev, "ioremap error\n");
 465                 return -ENOMEM;
 466         }
 467         irq = platform_get_irq(pdev, 0);
 468         if (irq < 0) {
 469                 dev_err(dev, "platform_get_irq failed:%d\n", irq);
 470                 return irq;
 471         }
 472         spin_lock_init(&bdc->lock);
 473         platform_set_drvdata(pdev, bdc);
 474         bdc->irq = irq;
 475         bdc->dev = dev;
 476         dev_dbg(bdc->dev, "bdc->regs: %p irq=%d\n", bdc->regs, bdc->irq);
 477
 478         temp = bdc_readl(bdc->regs, BDC_BDCSC);
 479         if ((temp & BDC_P64) &&
 480                         !dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64))) {
 481                 dev_dbg(bdc->dev, "Using 64-bit address\n");
 482         } else {
 483                 ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 484                 if (ret) {
 485                         dev_err(bdc->dev, "No suitable DMA config available, abort\n");
 486                         return -ENOTSUPP;
 487                 }
 488                 dev_dbg(bdc->dev, "Using 32-bit address\n");
 489         }
 490         ret = bdc_hw_init(bdc);
 491         if (ret) {
 492                 dev_err(bdc->dev, "BDC init failure:%d\n", ret);
 493                 return ret;
 494         }
 495         ret = bdc_udc_init(bdc);
 496         if (ret) {
 497                 dev_err(bdc->dev, "BDC Gadget init failure:%d\n", ret);
 498                 goto cleanup;
 499         }
 500         return 0;
 501
 502 cleanup:
 503         bdc_hw_exit(bdc);
 504
 505         return ret;
 506 }
 507
 508 static int bdc_remove(struct platform_device *pdev)
 509 {
 510         struct bdc *bdc;
 511
 512         bdc  = platform_get_drvdata(pdev);
 513         dev_dbg(bdc->dev, "%s ()\n", __func__);
 514         bdc_udc_exit(bdc);
 515         bdc_hw_exit(bdc);
 516
 517         return 0;
 518 }
 519
 520 static struct platform_driver bdc_driver = {
 521         .driver         = {
 522                 .name   = BRCM_BDC_NAME,
 523         },
 524         .probe          = bdc_probe,
 525         .remove         = bdc_remove,
 526 };
 527
 528 module_platform_driver(bdc_driver);
 529 MODULE_AUTHOR("Ashwini Pahuja <ashwini.linux@gmail.com>");
 530 MODULE_LICENSE("GPL");
 531 MODULE_DESCRIPTION(BRCM_BDC_DESC);