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

   1 /*
   2  * Copyright (c) 2012-2015 Qualcomm Atheros, Inc.
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include <linux/types.h>
  18 #include <linux/errno.h>
  19 #include <linux/fs.h>
  20 #include "wmi.h"
  21 #include "wil6210.h"
  22 #include "txrx.h"
  23 #include "pmc.h"
  24
  25 struct desc_alloc_info {
  26         dma_addr_t pa;
  27         void      *va;
  28 };
  29
  30 static int wil_is_pmc_allocated(struct pmc_ctx *pmc)
  31 {
  32         return !!pmc->pring_va;
  33 }
  34
  35 void wil_pmc_init(struct wil6210_priv *wil)
  36 {
  37         memset(&wil->pmc, 0, sizeof(struct pmc_ctx));
  38         mutex_init(&wil->pmc.lock);
  39 }
  40
  41 /**
  42  * Allocate the physical ring (p-ring) and the required
  43  * number of descriptors of required size.
  44  * Initialize the descriptors as required by pmc dma.
  45  * The descriptors' buffers dwords are initialized to hold
  46  * dword's serial number in the lsw and reserved value
  47  * PCM_DATA_INVALID_DW_VAL in the msw.
  48  */
  49 void wil_pmc_alloc(struct wil6210_priv *wil,
  50                    int num_descriptors,
  51                    int descriptor_size)
  52 {
  53         u32 i;
  54         struct pmc_ctx *pmc = &wil->pmc;
  55         struct device *dev = wil_to_dev(wil);
  56         struct wmi_pmc_cmd pmc_cmd = {0};
  57
  58         mutex_lock(&pmc->lock);
  59
  60         if (wil_is_pmc_allocated(pmc)) {
  61                 /* sanity check */
  62                 wil_err(wil, "%s: ERROR pmc is already allocated\n", __func__);
  63                 goto no_release_err;
  64         }
  65
  66         pmc->num_descriptors = num_descriptors;
  67         pmc->descriptor_size = descriptor_size;
  68
  69         wil_dbg_misc(wil, "%s: %d descriptors x %d bytes each\n",
  70                      __func__, num_descriptors, descriptor_size);
  71
  72         /* allocate descriptors info list in pmc context*/
  73         pmc->descriptors = kcalloc(num_descriptors,
  74                                   sizeof(struct desc_alloc_info),
  75                                   GFP_KERNEL);
  76         if (!pmc->descriptors) {
  77                 wil_err(wil, "%s: ERROR allocating pmc skb list\n", __func__);
  78                 goto no_release_err;
  79         }
  80
  81         wil_dbg_misc(wil,
  82                      "%s: allocated descriptors info list %p\n",
  83                      __func__, pmc->descriptors);
  84
  85         /* Allocate pring buffer and descriptors.
  86          * vring->va should be aligned on its size rounded up to power of 2
  87          * This is granted by the dma_alloc_coherent
  88          */
  89         pmc->pring_va = dma_alloc_coherent(dev,
  90                         sizeof(struct vring_tx_desc) * num_descriptors,
  91                         &pmc->pring_pa,
  92                         GFP_KERNEL);
  93
  94         wil_dbg_misc(wil,
  95                      "%s: allocated pring %p => %pad. %zd x %d = total %zd bytes\n",
  96                      __func__,
  97                      pmc->pring_va, &pmc->pring_pa,
  98                      sizeof(struct vring_tx_desc),
  99                      num_descriptors,
 100                      sizeof(struct vring_tx_desc) * num_descriptors);
 101
 102         if (!pmc->pring_va) {
 103                 wil_err(wil, "%s: ERROR allocating pmc pring\n", __func__);
 104                 goto release_pmc_skb_list;
 105         }
 106
 107         /* initially, all descriptors are SW owned
 108          * For Tx, Rx, and PMC, ownership bit is at the same location, thus
 109          * we can use any
 110          */
 111         for (i = 0; i < num_descriptors; i++) {
 112                 struct vring_tx_desc *_d = &pmc->pring_va[i];
 113                 struct vring_tx_desc dd = {}, *d = &dd;
 114                 int j = 0;
 115
 116                 pmc->descriptors[i].va = dma_alloc_coherent(dev,
 117                         descriptor_size,
 118                         &pmc->descriptors[i].pa,
 119                         GFP_KERNEL);
 120
 121                 if (unlikely(!pmc->descriptors[i].va)) {
 122                         wil_err(wil,
 123                                 "%s: ERROR allocating pmc descriptor %d",
 124                                 __func__, i);
 125                         goto release_pmc_skbs;
 126                 }
 127
 128                 for (j = 0; j < descriptor_size / sizeof(u32); j++) {
 129                         u32 *p = (u32 *)pmc->descriptors[i].va + j;
 130                         *p = PCM_DATA_INVALID_DW_VAL | j;
 131                 }
 132
 133                 /* configure dma descriptor */
 134                 d->dma.addr.addr_low =
 135                         cpu_to_le32(lower_32_bits(pmc->descriptors[i].pa));
 136                 d->dma.addr.addr_high =
 137                         cpu_to_le16((u16)upper_32_bits(pmc->descriptors[i].pa));
 138                 d->dma.status = 0; /* 0 = HW_OWNED */
 139                 d->dma.length = cpu_to_le16(descriptor_size);
 140                 d->dma.d0 = BIT(9) | RX_DMA_D0_CMD_DMA_IT;
 141                 *_d = *d;
 142         }
 143
 144         wil_dbg_misc(wil, "%s: allocated successfully\n", __func__);
 145
 146         pmc_cmd.op = WMI_PMC_ALLOCATE;
 147         pmc_cmd.ring_size = cpu_to_le16(pmc->num_descriptors);
 148         pmc_cmd.mem_base = cpu_to_le64(pmc->pring_pa);
 149
 150         wil_dbg_misc(wil, "%s: send WMI_PMC_CMD with ALLOCATE op\n", __func__);
 151         pmc->last_cmd_status = wmi_send(wil,
 152                                         WMI_PMC_CMDID,
 153                                         &pmc_cmd,
 154                                         sizeof(pmc_cmd));
 155         if (pmc->last_cmd_status) {
 156                 wil_err(wil,
 157                         "%s: WMI_PMC_CMD with ALLOCATE op failed with status %d",
 158                         __func__, pmc->last_cmd_status);
 159                 goto release_pmc_skbs;
 160         }
 161
 162         mutex_unlock(&pmc->lock);
 163
 164         return;
 165
 166 release_pmc_skbs:
 167         wil_err(wil, "%s: exit on error: Releasing skbs...\n", __func__);
 168         for (i = 0; pmc->descriptors[i].va && i < num_descriptors; i++) {
 169                 dma_free_coherent(dev,
 170                                   descriptor_size,
 171                                   pmc->descriptors[i].va,
 172                                   pmc->descriptors[i].pa);
 173
 174                 pmc->descriptors[i].va = NULL;
 175         }
 176         wil_err(wil, "%s: exit on error: Releasing pring...\n", __func__);
 177
 178         dma_free_coherent(dev,
 179                           sizeof(struct vring_tx_desc) * num_descriptors,
 180                           pmc->pring_va,
 181                           pmc->pring_pa);
 182
 183         pmc->pring_va = NULL;
 184
 185 release_pmc_skb_list:
 186         wil_err(wil, "%s: exit on error: Releasing descriptors info list...\n",
 187                 __func__);
 188         kfree(pmc->descriptors);
 189         pmc->descriptors = NULL;
 190
 191 no_release_err:
 192         pmc->last_cmd_status = -ENOMEM;
 193         mutex_unlock(&pmc->lock);
 194 }
 195
 196 /**
 197  * Traverse the p-ring and release all buffers.
 198  * At the end release the p-ring memory
 199  */
 200 void wil_pmc_free(struct wil6210_priv *wil, int send_pmc_cmd)
 201 {
 202         struct pmc_ctx *pmc = &wil->pmc;
 203         struct device *dev = wil_to_dev(wil);
 204         struct wmi_pmc_cmd pmc_cmd = {0};
 205
 206         mutex_lock(&pmc->lock);
 207
 208         pmc->last_cmd_status = 0;
 209
 210         if (!wil_is_pmc_allocated(pmc)) {
 211                 wil_dbg_misc(wil, "%s: Error, can't free - not allocated\n",
 212                              __func__);
 213                 pmc->last_cmd_status = -EPERM;
 214                 mutex_unlock(&pmc->lock);
 215                 return;
 216         }
 217
 218         if (send_pmc_cmd) {
 219                 wil_dbg_misc(wil, "%s: send WMI_PMC_CMD with RELEASE op\n",
 220                              __func__);
 221                 pmc_cmd.op = WMI_PMC_RELEASE;
 222                 pmc->last_cmd_status =
 223                                 wmi_send(wil, WMI_PMC_CMDID, &pmc_cmd,
 224                                          sizeof(pmc_cmd));
 225                 if (pmc->last_cmd_status) {
 226                         wil_err(wil,
 227                                 "%s WMI_PMC_CMD with RELEASE op failed, status %d",
 228                                 __func__, pmc->last_cmd_status);
 229                         /* There's nothing we can do with this error.
 230                          * Normally, it should never occur.
 231                          * Continue to freeing all memory allocated for pmc.
 232                          */
 233                 }
 234         }
 235
 236         if (pmc->pring_va) {
 237                 size_t buf_size = sizeof(struct vring_tx_desc) *
 238                                   pmc->num_descriptors;
 239
 240                 wil_dbg_misc(wil, "%s: free pring va %p\n",
 241                              __func__, pmc->pring_va);
 242                 dma_free_coherent(dev, buf_size, pmc->pring_va, pmc->pring_pa);
 243
 244                 pmc->pring_va = NULL;
 245         } else {
 246                 pmc->last_cmd_status = -ENOENT;
 247         }
 248
 249         if (pmc->descriptors) {
 250                 int i;
 251
 252                 for (i = 0;
 253                      pmc->descriptors[i].va && i < pmc->num_descriptors; i++) {
 254                         dma_free_coherent(dev,
 255                                           pmc->descriptor_size,
 256                                           pmc->descriptors[i].va,
 257                                           pmc->descriptors[i].pa);
 258                         pmc->descriptors[i].va = NULL;
 259                 }
 260                 wil_dbg_misc(wil, "%s: free descriptor info %d/%d\n",
 261                              __func__, i, pmc->num_descriptors);
 262                 wil_dbg_misc(wil,
 263                              "%s: free pmc descriptors info list %p\n",
 264                              __func__, pmc->descriptors);
 265                 kfree(pmc->descriptors);
 266                 pmc->descriptors = NULL;
 267         } else {
 268                 pmc->last_cmd_status = -ENOENT;
 269         }
 270
 271         mutex_unlock(&pmc->lock);
 272 }
 273
 274 /**
 275  * Status of the last operation requested via debugfs: alloc/free/read.
 276  * 0 - success or negative errno
 277  */
 278 int wil_pmc_last_cmd_status(struct wil6210_priv *wil)
 279 {
 280         wil_dbg_misc(wil, "%s: status %d\n", __func__,
 281                      wil->pmc.last_cmd_status);
 282
 283         return wil->pmc.last_cmd_status;
 284 }
 285
 286 /**
 287  * Read from required position up to the end of current descriptor,
 288  * depends on descriptor size configured during alloc request.
 289  */
 290 ssize_t wil_pmc_read(struct file *filp, char __user *buf, size_t count,
 291                      loff_t *f_pos)
 292 {
 293         struct wil6210_priv *wil = filp->private_data;
 294         struct pmc_ctx *pmc = &wil->pmc;
 295         size_t retval = 0;
 296         unsigned long long idx;
 297         loff_t offset;
 298         size_t pmc_size = pmc->descriptor_size * pmc->num_descriptors;
 299
 300         mutex_lock(&pmc->lock);
 301
 302         if (!wil_is_pmc_allocated(pmc)) {
 303                 wil_err(wil, "%s: error, pmc is not allocated!\n", __func__);
 304                 pmc->last_cmd_status = -EPERM;
 305                 mutex_unlock(&pmc->lock);
 306                 return -EPERM;
 307         }
 308
 309         wil_dbg_misc(wil,
 310                      "%s: size %u, pos %lld\n",
 311                      __func__, (unsigned)count, *f_pos);
 312
 313         pmc->last_cmd_status = 0;
 314
 315         idx = *f_pos;
 316         do_div(idx, pmc->descriptor_size);
 317         offset = *f_pos - (idx * pmc->descriptor_size);
 318
 319         if (*f_pos >= pmc_size) {
 320                 wil_dbg_misc(wil, "%s: reached end of pmc buf: %lld >= %u\n",
 321                              __func__, *f_pos, (unsigned)pmc_size);
 322                 pmc->last_cmd_status = -ERANGE;
 323                 goto out;
 324         }
 325
 326         wil_dbg_misc(wil,
 327                      "%s: read from pos %lld (descriptor %llu, offset %llu) %zu bytes\n",
 328                      __func__, *f_pos, idx, offset, count);
 329
 330         /* if no errors, return the copied byte count */
 331         retval = simple_read_from_buffer(buf,
 332                                          count,
 333                                          &offset,
 334                                          pmc->descriptors[idx].va,
 335                                          pmc->descriptor_size);
 336         *f_pos += retval;
 337 out:
 338         mutex_unlock(&pmc->lock);
 339
 340         return retval;
 341 }
 342
 343 loff_t wil_pmc_llseek(struct file *filp, loff_t off, int whence)
 344 {
 345         loff_t newpos;
 346         struct wil6210_priv *wil = filp->private_data;
 347         struct pmc_ctx *pmc = &wil->pmc;
 348         size_t pmc_size = pmc->descriptor_size * pmc->num_descriptors;
 349
 350         switch (whence) {
 351         case 0: /* SEEK_SET */
 352                 newpos = off;
 353                 break;
 354
 355         case 1: /* SEEK_CUR */
 356                 newpos = filp->f_pos + off;
 357                 break;
 358
 359         case 2: /* SEEK_END */
 360                 newpos = pmc_size;
 361                 break;
 362
 363         default: /* can't happen */
 364                 return -EINVAL;
 365         }
 366
 367         if (newpos < 0)
 368                 return -EINVAL;
 369         if (newpos > pmc_size)
 370                 newpos = pmc_size;
 371
 372         filp->f_pos = newpos;
 373
 374         return newpos;
 375 }