drivers/net/wireless/ath/wil6210/pmc.c

   1 // SPDX-License-Identifier: ISC
   2 /*
   3  * Copyright (c) 2012-2015,2017 Qualcomm Atheros, Inc.
   4  * Copyright (c) 2018, The Linux Foundation. All rights reserved.
   5  */
   6
   7 #include <linux/types.h>
   8 #include <linux/errno.h>
   9 #include <linux/fs.h>
  10 #include <linux/seq_file.h>
  11 #include "wmi.h"
  12 #include "wil6210.h"
  13 #include "txrx.h"
  14 #include "pmc.h"
  15
  16 struct desc_alloc_info {
  17         dma_addr_t pa;
  18         void      *va;
  19 };
  20
  21 static int wil_is_pmc_allocated(struct pmc_ctx *pmc)
  22 {
  23         return !!pmc->pring_va;
  24 }
  25
  26 void wil_pmc_init(struct wil6210_priv *wil)
  27 {
  28         memset(&wil->pmc, 0, sizeof(struct pmc_ctx));
  29         mutex_init(&wil->pmc.lock);
  30 }
  31
  32 /* Allocate the physical ring (p-ring) and the required
  33  * number of descriptors of required size.
  34  * Initialize the descriptors as required by pmc dma.
  35  * The descriptors' buffers dwords are initialized to hold
  36  * dword's serial number in the lsw and reserved value
  37  * PCM_DATA_INVALID_DW_VAL in the msw.
  38  */
  39 void wil_pmc_alloc(struct wil6210_priv *wil,
  40                    int num_descriptors,
  41                    int descriptor_size)
  42 {
  43         u32 i;
  44         struct pmc_ctx *pmc = &wil->pmc;
  45         struct device *dev = wil_to_dev(wil);
  46         struct wil6210_vif *vif = ndev_to_vif(wil->main_ndev);
  47         struct wmi_pmc_cmd pmc_cmd = {0};
  48         int last_cmd_err = -ENOMEM;
  49
  50         mutex_lock(&pmc->lock);
  51
  52         if (wil_is_pmc_allocated(pmc)) {
  53                 /* sanity check */
  54                 wil_err(wil, "ERROR pmc is already allocated\n");
  55                 goto no_release_err;
  56         }
  57         if ((num_descriptors <= 0) || (descriptor_size <= 0)) {
  58                 wil_err(wil,
  59                         "Invalid params num_descriptors(%d), descriptor_size(%d)\n",
  60                         num_descriptors, descriptor_size);
  61                 last_cmd_err = -EINVAL;
  62                 goto no_release_err;
  63         }
  64
  65         if (num_descriptors > (1 << WIL_RING_SIZE_ORDER_MAX)) {
  66                 wil_err(wil,
  67                         "num_descriptors(%d) exceeds max ring size %d\n",
  68                         num_descriptors, 1 << WIL_RING_SIZE_ORDER_MAX);
  69                 last_cmd_err = -EINVAL;
  70                 goto no_release_err;
  71         }
  72
  73         if (num_descriptors > INT_MAX / descriptor_size) {
  74                 wil_err(wil,
  75                         "Overflow in num_descriptors(%d)*descriptor_size(%d)\n",
  76                         num_descriptors, descriptor_size);
  77                 last_cmd_err = -EINVAL;
  78                 goto no_release_err;
  79         }
  80
  81         pmc->num_descriptors = num_descriptors;
  82         pmc->descriptor_size = descriptor_size;
  83
  84         wil_dbg_misc(wil, "pmc_alloc: %d descriptors x %d bytes each\n",
  85                      num_descriptors, descriptor_size);
  86
  87         /* allocate descriptors info list in pmc context*/
  88         pmc->descriptors = kcalloc(num_descriptors,
  89                                   sizeof(struct desc_alloc_info),
  90                                   GFP_KERNEL);
  91         if (!pmc->descriptors) {
  92                 wil_err(wil, "ERROR allocating pmc skb list\n");
  93                 goto no_release_err;
  94         }
  95
  96         wil_dbg_misc(wil, "pmc_alloc: allocated descriptors info list %p\n",
  97                      pmc->descriptors);
  98
  99         /* Allocate pring buffer and descriptors.
 100          * vring->va should be aligned on its size rounded up to power of 2
 101          * This is granted by the dma_alloc_coherent.
 102          *
 103          * HW has limitation that all vrings addresses must share the same
 104          * upper 16 msb bits part of 48 bits address. To workaround that,
 105          * if we are using more than 32 bit addresses switch to 32 bit
 106          * allocation before allocating vring memory.
 107          *
 108          * There's no check for the return value of dma_set_mask_and_coherent,
 109          * since we assume if we were able to set the mask during
 110          * initialization in this system it will not fail if we set it again
 111          */
 112         if (wil->dma_addr_size > 32)
 113                 dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
 114
 115         pmc->pring_va = dma_alloc_coherent(dev,
 116                         sizeof(struct vring_tx_desc) * num_descriptors,
 117                         &pmc->pring_pa,
 118                         GFP_KERNEL);
 119
 120         if (wil->dma_addr_size > 32)
 121                 dma_set_mask_and_coherent(dev,
 122                                           DMA_BIT_MASK(wil->dma_addr_size));
 123
 124         wil_dbg_misc(wil,
 125                      "pmc_alloc: allocated pring %p => %pad. %zd x %d = total %zd bytes\n",
 126                      pmc->pring_va, &pmc->pring_pa,
 127                      sizeof(struct vring_tx_desc),
 128                      num_descriptors,
 129                      sizeof(struct vring_tx_desc) * num_descriptors);
 130
 131         if (!pmc->pring_va) {
 132                 wil_err(wil, "ERROR allocating pmc pring\n");
 133                 goto release_pmc_skb_list;
 134         }
 135
 136         /* initially, all descriptors are SW owned
 137          * For Tx, Rx, and PMC, ownership bit is at the same location, thus
 138          * we can use any
 139          */
 140         for (i = 0; i < num_descriptors; i++) {
 141                 struct vring_tx_desc *_d = &pmc->pring_va[i];
 142                 struct vring_tx_desc dd = {}, *d = &dd;
 143                 int j = 0;
 144
 145                 pmc->descriptors[i].va = dma_alloc_coherent(dev,
 146                         descriptor_size,
 147                         &pmc->descriptors[i].pa,
 148                         GFP_KERNEL);
 149
 150                 if (unlikely(!pmc->descriptors[i].va)) {
 151                         wil_err(wil, "ERROR allocating pmc descriptor %d", i);
 152                         goto release_pmc_skbs;
 153                 }
 154
 155                 for (j = 0; j < descriptor_size / sizeof(u32); j++) {
 156                         u32 *p = (u32 *)pmc->descriptors[i].va + j;
 157                         *p = PCM_DATA_INVALID_DW_VAL | j;
 158                 }
 159
 160                 /* configure dma descriptor */
 161                 d->dma.addr.addr_low =
 162                         cpu_to_le32(lower_32_bits(pmc->descriptors[i].pa));
 163                 d->dma.addr.addr_high =
 164                         cpu_to_le16((u16)upper_32_bits(pmc->descriptors[i].pa));
 165                 d->dma.status = 0; /* 0 = HW_OWNED */
 166                 d->dma.length = cpu_to_le16(descriptor_size);
 167                 d->dma.d0 = BIT(9) | RX_DMA_D0_CMD_DMA_IT;
 168                 *_d = *d;
 169         }
 170
 171         wil_dbg_misc(wil, "pmc_alloc: allocated successfully\n");
 172
 173         pmc_cmd.op = WMI_PMC_ALLOCATE;
 174         pmc_cmd.ring_size = cpu_to_le16(pmc->num_descriptors);
 175         pmc_cmd.mem_base = cpu_to_le64(pmc->pring_pa);
 176
 177         wil_dbg_misc(wil, "pmc_alloc: send WMI_PMC_CMD with ALLOCATE op\n");
 178         pmc->last_cmd_status = wmi_send(wil,
 179                                         WMI_PMC_CMDID,
 180                                         vif->mid,
 181                                         &pmc_cmd,
 182                                         sizeof(pmc_cmd));
 183         if (pmc->last_cmd_status) {
 184                 wil_err(wil,
 185                         "WMI_PMC_CMD with ALLOCATE op failed with status %d",
 186                         pmc->last_cmd_status);
 187                 goto release_pmc_skbs;
 188         }
 189
 190         mutex_unlock(&pmc->lock);
 191
 192         return;
 193
 194 release_pmc_skbs:
 195         wil_err(wil, "exit on error: Releasing skbs...\n");
 196         for (i = 0; i < num_descriptors && pmc->descriptors[i].va; i++) {
 197                 dma_free_coherent(dev,
 198                                   descriptor_size,
 199                                   pmc->descriptors[i].va,
 200                                   pmc->descriptors[i].pa);
 201
 202                 pmc->descriptors[i].va = NULL;
 203         }
 204         wil_err(wil, "exit on error: Releasing pring...\n");
 205
 206         dma_free_coherent(dev,
 207                           sizeof(struct vring_tx_desc) * num_descriptors,
 208                           pmc->pring_va,
 209                           pmc->pring_pa);
 210
 211         pmc->pring_va = NULL;
 212
 213 release_pmc_skb_list:
 214         wil_err(wil, "exit on error: Releasing descriptors info list...\n");
 215         kfree(pmc->descriptors);
 216         pmc->descriptors = NULL;
 217
 218 no_release_err:
 219         pmc->last_cmd_status = last_cmd_err;
 220         mutex_unlock(&pmc->lock);
 221 }
 222
 223 /* Traverse the p-ring and release all buffers.
 224  * At the end release the p-ring memory
 225  */
 226 void wil_pmc_free(struct wil6210_priv *wil, int send_pmc_cmd)
 227 {
 228         struct pmc_ctx *pmc = &wil->pmc;
 229         struct device *dev = wil_to_dev(wil);
 230         struct wil6210_vif *vif = ndev_to_vif(wil->main_ndev);
 231         struct wmi_pmc_cmd pmc_cmd = {0};
 232
 233         mutex_lock(&pmc->lock);
 234
 235         pmc->last_cmd_status = 0;
 236
 237         if (!wil_is_pmc_allocated(pmc)) {
 238                 wil_dbg_misc(wil,
 239                              "pmc_free: Error, can't free - not allocated\n");
 240                 pmc->last_cmd_status = -EPERM;
 241                 mutex_unlock(&pmc->lock);
 242                 return;
 243         }
 244
 245         if (send_pmc_cmd) {
 246                 wil_dbg_misc(wil, "send WMI_PMC_CMD with RELEASE op\n");
 247                 pmc_cmd.op = WMI_PMC_RELEASE;
 248                 pmc->last_cmd_status =
 249                                 wmi_send(wil, WMI_PMC_CMDID, vif->mid,
 250                                          &pmc_cmd, sizeof(pmc_cmd));
 251                 if (pmc->last_cmd_status) {
 252                         wil_err(wil,
 253                                 "WMI_PMC_CMD with RELEASE op failed, status %d",
 254                                 pmc->last_cmd_status);
 255                         /* There's nothing we can do with this error.
 256                          * Normally, it should never occur.
 257                          * Continue to freeing all memory allocated for pmc.
 258                          */
 259                 }
 260         }
 261
 262         if (pmc->pring_va) {
 263                 size_t buf_size = sizeof(struct vring_tx_desc) *
 264                                   pmc->num_descriptors;
 265
 266                 wil_dbg_misc(wil, "pmc_free: free pring va %p\n",
 267                              pmc->pring_va);
 268                 dma_free_coherent(dev, buf_size, pmc->pring_va, pmc->pring_pa);
 269
 270                 pmc->pring_va = NULL;
 271         } else {
 272                 pmc->last_cmd_status = -ENOENT;
 273         }
 274
 275         if (pmc->descriptors) {
 276                 int i;
 277
 278                 for (i = 0;
 279                      i < pmc->num_descriptors && pmc->descriptors[i].va; i++) {
 280                         dma_free_coherent(dev,
 281                                           pmc->descriptor_size,
 282                                           pmc->descriptors[i].va,
 283                                           pmc->descriptors[i].pa);
 284                         pmc->descriptors[i].va = NULL;
 285                 }
 286                 wil_dbg_misc(wil, "pmc_free: free descriptor info %d/%d\n", i,
 287                              pmc->num_descriptors);
 288                 wil_dbg_misc(wil,
 289                              "pmc_free: free pmc descriptors info list %p\n",
 290                              pmc->descriptors);
 291                 kfree(pmc->descriptors);
 292                 pmc->descriptors = NULL;
 293         } else {
 294                 pmc->last_cmd_status = -ENOENT;
 295         }
 296
 297         mutex_unlock(&pmc->lock);
 298 }
 299
 300 /* Status of the last operation requested via debugfs: alloc/free/read.
 301  * 0 - success or negative errno
 302  */
 303 int wil_pmc_last_cmd_status(struct wil6210_priv *wil)
 304 {
 305         wil_dbg_misc(wil, "pmc_last_cmd_status: status %d\n",
 306                      wil->pmc.last_cmd_status);
 307
 308         return wil->pmc.last_cmd_status;
 309 }
 310
 311 /* Read from required position up to the end of current descriptor,
 312  * depends on descriptor size configured during alloc request.
 313  */
 314 ssize_t wil_pmc_read(struct file *filp, char __user *buf, size_t count,
 315                      loff_t *f_pos)
 316 {
 317         struct wil6210_priv *wil = filp->private_data;
 318         struct pmc_ctx *pmc = &wil->pmc;
 319         size_t retval = 0;
 320         unsigned long long idx;
 321         loff_t offset;
 322         size_t pmc_size;
 323
 324         mutex_lock(&pmc->lock);
 325
 326         if (!wil_is_pmc_allocated(pmc)) {
 327                 wil_err(wil, "error, pmc is not allocated!\n");
 328                 pmc->last_cmd_status = -EPERM;
 329                 mutex_unlock(&pmc->lock);
 330                 return -EPERM;
 331         }
 332
 333         pmc_size = pmc->descriptor_size * pmc->num_descriptors;
 334
 335         wil_dbg_misc(wil,
 336                      "pmc_read: size %u, pos %lld\n",
 337                      (u32)count, *f_pos);
 338
 339         pmc->last_cmd_status = 0;
 340
 341         idx = *f_pos;
 342         do_div(idx, pmc->descriptor_size);
 343         offset = *f_pos - (idx * pmc->descriptor_size);
 344
 345         if (*f_pos >= pmc_size) {
 346                 wil_dbg_misc(wil,
 347                              "pmc_read: reached end of pmc buf: %lld >= %u\n",
 348                              *f_pos, (u32)pmc_size);
 349                 pmc->last_cmd_status = -ERANGE;
 350                 goto out;
 351         }
 352
 353         wil_dbg_misc(wil,
 354                      "pmc_read: read from pos %lld (descriptor %llu, offset %llu) %zu bytes\n",
 355                      *f_pos, idx, offset, count);
 356
 357         /* if no errors, return the copied byte count */
 358         retval = simple_read_from_buffer(buf,
 359                                          count,
 360                                          &offset,
 361                                          pmc->descriptors[idx].va,
 362                                          pmc->descriptor_size);
 363         *f_pos += retval;
 364 out:
 365         mutex_unlock(&pmc->lock);
 366
 367         return retval;
 368 }
 369
 370 loff_t wil_pmc_llseek(struct file *filp, loff_t off, int whence)
 371 {
 372         loff_t newpos;
 373         struct wil6210_priv *wil = filp->private_data;
 374         struct pmc_ctx *pmc = &wil->pmc;
 375         size_t pmc_size;
 376
 377         mutex_lock(&pmc->lock);
 378
 379         if (!wil_is_pmc_allocated(pmc)) {
 380                 wil_err(wil, "error, pmc is not allocated!\n");
 381                 pmc->last_cmd_status = -EPERM;
 382                 mutex_unlock(&pmc->lock);
 383                 return -EPERM;
 384         }
 385
 386         pmc_size = pmc->descriptor_size * pmc->num_descriptors;
 387
 388         switch (whence) {
 389         case 0: /* SEEK_SET */
 390                 newpos = off;
 391                 break;
 392
 393         case 1: /* SEEK_CUR */
 394                 newpos = filp->f_pos + off;
 395                 break;
 396
 397         case 2: /* SEEK_END */
 398                 newpos = pmc_size;
 399                 break;
 400
 401         default: /* can't happen */
 402                 newpos = -EINVAL;
 403                 goto out;
 404         }
 405
 406         if (newpos < 0) {
 407                 newpos = -EINVAL;
 408                 goto out;
 409         }
 410         if (newpos > pmc_size)
 411                 newpos = pmc_size;
 412
 413         filp->f_pos = newpos;
 414
 415 out:
 416         mutex_unlock(&pmc->lock);
 417
 418         return newpos;
 419 }
 420
 421 int wil_pmcring_read(struct seq_file *s, void *data)
 422 {
 423         struct wil6210_priv *wil = s->private;
 424         struct pmc_ctx *pmc = &wil->pmc;
 425         size_t pmc_ring_size =
 426                 sizeof(struct vring_rx_desc) * pmc->num_descriptors;
 427
 428         mutex_lock(&pmc->lock);
 429
 430         if (!wil_is_pmc_allocated(pmc)) {
 431                 wil_err(wil, "error, pmc is not allocated!\n");
 432                 pmc->last_cmd_status = -EPERM;
 433                 mutex_unlock(&pmc->lock);
 434                 return -EPERM;
 435         }
 436
 437         wil_dbg_misc(wil, "pmcring_read: size %zu\n", pmc_ring_size);
 438
 439         seq_write(s, pmc->pring_va, pmc_ring_size);
 440
 441         mutex_unlock(&pmc->lock);
 442
 443         return 0;
 444 }