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         if (bdc->bd_table_pool)
 328                 dma_pool_destroy(bdc->bd_table_pool);
 329
 330         /* Free the bdc_ep array */
 331         kfree(bdc->bdc_ep_array);
 332
 333         bdc->srr.sr_bds = NULL;
 334         bdc->scratchpad.buff = NULL;
 335         bdc->bd_table_pool = NULL;
 336         bdc->bdc_ep_array = NULL;
 337 }
 338
 339 /*
 340  * bdc reinit gives a controller reset and reinitialize the registers,
 341  * called from disconnect/bus reset scenario's, to ensure proper HW cleanup
 342  */
 343 int bdc_reinit(struct bdc *bdc)
 344 {
 345         int ret;
 346
 347         dev_dbg(bdc->dev, "%s\n", __func__);
 348         ret = bdc_stop(bdc);
 349         if (ret)
 350                 goto out;
 351
 352         ret = bdc_reset(bdc);
 353         if (ret)
 354                 goto out;
 355
 356         /* the reinit flag is 1 */
 357         bdc_mem_init(bdc, true);
 358         ret = bdc_run(bdc);
 359 out:
 360         bdc->reinit = false;
 361
 362         return ret;
 363 }
 364
 365 /* Allocate all the dyanmic memory */
 366 static int bdc_mem_alloc(struct bdc *bdc)
 367 {
 368         u32 page_size;
 369         unsigned int num_ieps, num_oeps;
 370
 371         dev_dbg(bdc->dev,
 372                 "%s() NUM_BDS_PER_TABLE:%d\n", __func__,
 373                 NUM_BDS_PER_TABLE);
 374         page_size = BDC_PGS(bdc_readl(bdc->regs, BDC_BDCCFG0));
 375         /* page size is 2^pgs KB */
 376         page_size = 1 << page_size;
 377         /* KB */
 378         page_size <<= 10;
 379         dev_dbg(bdc->dev, "page_size=%d\n", page_size);
 380
 381         /* Create a pool of bd tables */
 382         bdc->bd_table_pool =
 383             dma_pool_create("BDC BD tables", bdc->dev, NUM_BDS_PER_TABLE * 16,
 384                                                                 16, page_size);
 385
 386         if (!bdc->bd_table_pool)
 387                 goto fail;
 388
 389         if (scratchpad_setup(bdc))
 390                 goto fail;
 391
 392         /* read from regs */
 393         num_ieps = NUM_NCS(bdc_readl(bdc->regs, BDC_FSCNIC));
 394         num_oeps = NUM_NCS(bdc_readl(bdc->regs, BDC_FSCNOC));
 395         /* +2: 1 for ep0 and the other is rsvd i.e. bdc_ep[0] is rsvd */
 396         bdc->num_eps = num_ieps + num_oeps + 2;
 397         dev_dbg(bdc->dev,
 398                 "ieps:%d eops:%d num_eps:%d\n",
 399                 num_ieps, num_oeps, bdc->num_eps);
 400         /* allocate array of ep pointers */
 401         bdc->bdc_ep_array = kcalloc(bdc->num_eps, sizeof(struct bdc_ep *),
 402                                                                 GFP_KERNEL);
 403         if (!bdc->bdc_ep_array)
 404                 goto fail;
 405
 406         dev_dbg(bdc->dev, "Allocating sr report0\n");
 407         if (setup_srr(bdc, 0))
 408                 goto fail;
 409
 410         return 0;
 411 fail:
 412         dev_warn(bdc->dev, "Couldn't initialize memory\n");
 413         bdc_mem_free(bdc);
 414
 415         return -ENOMEM;
 416 }
 417
 418 /* opposite to bdc_hw_init */
 419 static void bdc_hw_exit(struct bdc *bdc)
 420 {
 421         dev_dbg(bdc->dev, "%s ()\n", __func__);
 422         bdc_mem_free(bdc);
 423 }
 424
 425 /* Initialize the bdc HW and memory */
 426 static int bdc_hw_init(struct bdc *bdc)
 427 {
 428         int ret;
 429
 430         dev_dbg(bdc->dev, "%s ()\n", __func__);
 431         ret = bdc_reset(bdc);
 432         if (ret) {
 433                 dev_err(bdc->dev, "err resetting bdc abort bdc init%d\n", ret);
 434                 return ret;
 435         }
 436         ret = bdc_mem_alloc(bdc);
 437         if (ret) {
 438                 dev_err(bdc->dev, "Mem alloc failed, aborting\n");
 439                 return -ENOMEM;
 440         }
 441         bdc_mem_init(bdc, 0);
 442         bdc_dbg_regs(bdc);
 443         dev_dbg(bdc->dev, "HW Init done\n");
 444
 445         return 0;
 446 }
 447
 448 static int bdc_probe(struct platform_device *pdev)
 449 {
 450         struct bdc *bdc;
 451         struct resource *res;
 452         int ret = -ENOMEM;
 453         int irq;
 454         u32 temp;
 455         struct device *dev = &pdev->dev;
 456
 457         dev_dbg(dev, "%s()\n", __func__);
 458         bdc = devm_kzalloc(dev, sizeof(*bdc), GFP_KERNEL);
 459         if (!bdc)
 460                 return -ENOMEM;
 461
 462         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 463         bdc->regs = devm_ioremap_resource(dev, res);
 464         if (IS_ERR(bdc->regs)) {
 465                 dev_err(dev, "ioremap error\n");
 466                 return -ENOMEM;
 467         }
 468         irq = platform_get_irq(pdev, 0);
 469         if (irq < 0) {
 470                 dev_err(dev, "platform_get_irq failed:%d\n", irq);
 471                 return irq;
 472         }
 473         spin_lock_init(&bdc->lock);
 474         platform_set_drvdata(pdev, bdc);
 475         bdc->irq = irq;
 476         bdc->dev = dev;
 477         dev_dbg(bdc->dev, "bdc->regs: %p irq=%d\n", bdc->regs, bdc->irq);
 478
 479         temp = bdc_readl(bdc->regs, BDC_BDCSC);
 480         if ((temp & BDC_P64) &&
 481                         !dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64))) {
 482                 dev_dbg(bdc->dev, "Using 64-bit address\n");
 483         } else {
 484                 ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 485                 if (ret) {
 486                         dev_err(bdc->dev, "No suitable DMA config available, abort\n");
 487                         return -ENOTSUPP;
 488                 }
 489                 dev_dbg(bdc->dev, "Using 32-bit address\n");
 490         }
 491         ret = bdc_hw_init(bdc);
 492         if (ret) {
 493                 dev_err(bdc->dev, "BDC init failure:%d\n", ret);
 494                 return ret;
 495         }
 496         ret = bdc_udc_init(bdc);
 497         if (ret) {
 498                 dev_err(bdc->dev, "BDC Gadget init failure:%d\n", ret);
 499                 goto cleanup;
 500         }
 501         return 0;
 502
 503 cleanup:
 504         bdc_hw_exit(bdc);
 505
 506         return ret;
 507 }
 508
 509 static int bdc_remove(struct platform_device *pdev)
 510 {
 511         struct bdc *bdc;
 512
 513         bdc  = platform_get_drvdata(pdev);
 514         dev_dbg(bdc->dev, "%s ()\n", __func__);
 515         bdc_udc_exit(bdc);
 516         bdc_hw_exit(bdc);
 517
 518         return 0;
 519 }
 520
 521 static struct platform_driver bdc_driver = {
 522         .driver         = {
 523                 .name   = BRCM_BDC_NAME,
 524         },
 525         .probe          = bdc_probe,
 526         .remove         = bdc_remove,
 527 };
 528
 529 module_platform_driver(bdc_driver);
 530 MODULE_AUTHOR("Ashwini Pahuja <ashwini.linux@gmail.com>");
 531 MODULE_LICENSE("GPL");
 532 MODULE_DESCRIPTION(BRCM_BDC_DESC);