drivers/media/pci/saa7164/saa7164-buffer.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Driver for the NXP SAA7164 PCIe bridge
   4  *
   5  *  Copyright (c) 2010-2015 Steven Toth <stoth@kernellabs.com>
   6  */
   7
   8 #include <linux/slab.h>
   9
  10 #include "saa7164.h"
  11
  12 /* The PCI address space for buffer handling looks like this:
  13  *
  14  * +-u32 wide-------------+
  15  * |                      +
  16  * +-u64 wide------------------------------------+
  17  * +                                             +
  18  * +----------------------+
  19  * | CurrentBufferPtr     + Pointer to current PCI buffer >-+
  20  * +----------------------+                                 |
  21  * | Unused               +                                 |
  22  * +----------------------+                                 |
  23  * | Pitch                + = 188 (bytes)                   |
  24  * +----------------------+                                 |
  25  * | PCI buffer size      + = pitch * number of lines (312) |
  26  * +----------------------+                                 |
  27  * |0| Buf0 Write Offset  +                                 |
  28  * +----------------------+                                 v
  29  * |1| Buf1 Write Offset  +                                 |
  30  * +----------------------+                                 |
  31  * |2| Buf2 Write Offset  +                                 |
  32  * +----------------------+                                 |
  33  * |3| Buf3 Write Offset  +                                 |
  34  * +----------------------+                                 |
  35  * ... More write offsets                                   |
  36  * +---------------------------------------------+          |
  37  * +0| set of ptrs to PCI pagetables             +          |
  38  * +---------------------------------------------+          |
  39  * +1| set of ptrs to PCI pagetables             + <--------+
  40  * +---------------------------------------------+
  41  * +2| set of ptrs to PCI pagetables             +
  42  * +---------------------------------------------+
  43  * +3| set of ptrs to PCI pagetables             + >--+
  44  * +---------------------------------------------+    |
  45  * ... More buffer pointers                           |  +----------------+
  46  *                                                  +->| pt[0] TS data  |
  47  *                                                  |  +----------------+
  48  *                                                  |
  49  *                                                  |  +----------------+
  50  *                                                  +->| pt[1] TS data  |
  51  *                                                  |  +----------------+
  52  *                                                  | etc
  53  */
  54
  55 void saa7164_buffer_display(struct saa7164_buffer *buf)
  56 {
  57         struct saa7164_dev *dev = buf->port->dev;
  58         int i;
  59
  60         dprintk(DBGLVL_BUF, "%s()   buffer @ 0x%p nr=%d\n",
  61                 __func__, buf, buf->idx);
  62         dprintk(DBGLVL_BUF, "  pci_cpu @ 0x%p    dma @ 0x%08llx len = 0x%x\n",
  63                 buf->cpu, (long long)buf->dma, buf->pci_size);
  64         dprintk(DBGLVL_BUF, "   pt_cpu @ 0x%p pt_dma @ 0x%08llx len = 0x%x\n",
  65                 buf->pt_cpu, (long long)buf->pt_dma, buf->pt_size);
  66
  67         /* Format the Page Table Entries to point into the data buffer */
  68         for (i = 0 ; i < SAA7164_PT_ENTRIES; i++) {
  69
  70                 dprintk(DBGLVL_BUF, "    pt[%02d] = 0x%p -> 0x%llx\n",
  71                         i, buf->pt_cpu, (u64)*(buf->pt_cpu));
  72
  73         }
  74 }
  75 /* Allocate a new buffer structure and associated PCI space in bytes.
  76  * len must be a multiple of sizeof(u64)
  77  */
  78 struct saa7164_buffer *saa7164_buffer_alloc(struct saa7164_port *port,
  79         u32 len)
  80 {
  81         struct tmHWStreamParameters *params = &port->hw_streamingparams;
  82         struct saa7164_buffer *buf = NULL;
  83         struct saa7164_dev *dev = port->dev;
  84         int i;
  85
  86         if ((len == 0) || (len >= 65536) || (len % sizeof(u64))) {
  87                 log_warn("%s() SAA_ERR_BAD_PARAMETER\n", __func__);
  88                 goto ret;
  89         }
  90
  91         buf = kzalloc(sizeof(*buf), GFP_KERNEL);
  92         if (!buf)
  93                 goto ret;
  94
  95         buf->idx = -1;
  96         buf->port = port;
  97         buf->flags = SAA7164_BUFFER_FREE;
  98         buf->pos = 0;
  99         buf->actual_size = params->pitch * params->numberoflines;
 100         buf->crc = 0;
 101         /* TODO: arg len is being ignored */
 102         buf->pci_size = SAA7164_PT_ENTRIES * 0x1000;
 103         buf->pt_size = (SAA7164_PT_ENTRIES * sizeof(u64)) + 0x1000;
 104
 105         /* Allocate contiguous memory */
 106         buf->cpu = dma_alloc_coherent(&port->dev->pci->dev, buf->pci_size,
 107                                       &buf->dma, GFP_KERNEL);
 108         if (!buf->cpu)
 109                 goto fail1;
 110
 111         buf->pt_cpu = dma_alloc_coherent(&port->dev->pci->dev, buf->pt_size,
 112                                          &buf->pt_dma, GFP_KERNEL);
 113         if (!buf->pt_cpu)
 114                 goto fail2;
 115
 116         /* init the buffers to a known pattern, easier during debugging */
 117         memset(buf->cpu, 0xff, buf->pci_size);
 118         buf->crc = crc32(0, buf->cpu, buf->actual_size);
 119         memset(buf->pt_cpu, 0xff, buf->pt_size);
 120
 121         dprintk(DBGLVL_BUF, "%s()   allocated buffer @ 0x%p (%d pageptrs)\n",
 122                 __func__, buf, params->numpagetables);
 123         dprintk(DBGLVL_BUF, "  pci_cpu @ 0x%p    dma @ 0x%08lx len = 0x%x\n",
 124                 buf->cpu, (long)buf->dma, buf->pci_size);
 125         dprintk(DBGLVL_BUF, "   pt_cpu @ 0x%p pt_dma @ 0x%08lx len = 0x%x\n",
 126                 buf->pt_cpu, (long)buf->pt_dma, buf->pt_size);
 127
 128         /* Format the Page Table Entries to point into the data buffer */
 129         for (i = 0 ; i < params->numpagetables; i++) {
 130
 131                 *(buf->pt_cpu + i) = buf->dma + (i * 0x1000); /* TODO */
 132                 dprintk(DBGLVL_BUF, "    pt[%02d] = 0x%p -> 0x%llx\n",
 133                         i, buf->pt_cpu, (u64)*(buf->pt_cpu));
 134
 135         }
 136
 137         goto ret;
 138
 139 fail2:
 140         dma_free_coherent(&port->dev->pci->dev, buf->pci_size, buf->cpu,
 141                           buf->dma);
 142 fail1:
 143         kfree(buf);
 144
 145         buf = NULL;
 146 ret:
 147         return buf;
 148 }
 149
 150 int saa7164_buffer_dealloc(struct saa7164_buffer *buf)
 151 {
 152         struct saa7164_dev *dev;
 153
 154         if (!buf || !buf->port)
 155                 return SAA_ERR_BAD_PARAMETER;
 156         dev = buf->port->dev;
 157
 158         dprintk(DBGLVL_BUF, "%s() deallocating buffer @ 0x%p\n",
 159                 __func__, buf);
 160
 161         if (buf->flags != SAA7164_BUFFER_FREE)
 162                 log_warn(" freeing a non-free buffer\n");
 163
 164         dma_free_coherent(&dev->pci->dev, buf->pci_size, buf->cpu, buf->dma);
 165         dma_free_coherent(&dev->pci->dev, buf->pt_size, buf->pt_cpu,
 166                           buf->pt_dma);
 167
 168         kfree(buf);
 169
 170         return SAA_OK;
 171 }
 172
 173 int saa7164_buffer_zero_offsets(struct saa7164_port *port, int i)
 174 {
 175         struct saa7164_dev *dev = port->dev;
 176
 177         if ((i < 0) || (i >= port->hwcfg.buffercount))
 178                 return -EINVAL;
 179
 180         dprintk(DBGLVL_BUF, "%s(idx = %d)\n", __func__, i);
 181
 182         saa7164_writel(port->bufoffset + (sizeof(u32) * i), 0);
 183
 184         return 0;
 185 }
 186
 187 /* Write a buffer into the hardware */
 188 int saa7164_buffer_activate(struct saa7164_buffer *buf, int i)
 189 {
 190         struct saa7164_port *port = buf->port;
 191         struct saa7164_dev *dev = port->dev;
 192
 193         if ((i < 0) || (i >= port->hwcfg.buffercount))
 194                 return -EINVAL;
 195
 196         dprintk(DBGLVL_BUF, "%s(idx = %d)\n", __func__, i);
 197
 198         buf->idx = i; /* Note of which buffer list index position we occupy */
 199         buf->flags = SAA7164_BUFFER_BUSY;
 200         buf->pos = 0;
 201
 202         /* TODO: Review this in light of 32v64 assignments */
 203         saa7164_writel(port->bufoffset + (sizeof(u32) * i), 0);
 204         saa7164_writel(port->bufptr32h + ((sizeof(u32) * 2) * i), buf->pt_dma);
 205         saa7164_writel(port->bufptr32l + ((sizeof(u32) * 2) * i), 0);
 206
 207         dprintk(DBGLVL_BUF, "   buf[%d] offset 0x%llx (0x%x) buf 0x%llx/%llx (0x%x/%x) nr=%d\n",
 208                 buf->idx,
 209                 (u64)port->bufoffset + (i * sizeof(u32)),
 210                 saa7164_readl(port->bufoffset + (sizeof(u32) * i)),
 211                 (u64)port->bufptr32h + ((sizeof(u32) * 2) * i),
 212                 (u64)port->bufptr32l + ((sizeof(u32) * 2) * i),
 213                 saa7164_readl(port->bufptr32h + ((sizeof(u32) * i) * 2)),
 214                 saa7164_readl(port->bufptr32l + ((sizeof(u32) * i) * 2)),
 215                 buf->idx);
 216
 217         return 0;
 218 }
 219
 220 int saa7164_buffer_cfg_port(struct saa7164_port *port)
 221 {
 222         struct tmHWStreamParameters *params = &port->hw_streamingparams;
 223         struct saa7164_dev *dev = port->dev;
 224         struct saa7164_buffer *buf;
 225         struct list_head *c, *n;
 226         int i = 0;
 227
 228         dprintk(DBGLVL_BUF, "%s(port=%d)\n", __func__, port->nr);
 229
 230         saa7164_writel(port->bufcounter, 0);
 231         saa7164_writel(port->pitch, params->pitch);
 232         saa7164_writel(port->bufsize, params->pitch * params->numberoflines);
 233
 234         dprintk(DBGLVL_BUF, " configured:\n");
 235         dprintk(DBGLVL_BUF, "   lmmio       0x%p\n", dev->lmmio);
 236         dprintk(DBGLVL_BUF, "   bufcounter  0x%x = 0x%x\n", port->bufcounter,
 237                 saa7164_readl(port->bufcounter));
 238
 239         dprintk(DBGLVL_BUF, "   pitch       0x%x = %d\n", port->pitch,
 240                 saa7164_readl(port->pitch));
 241
 242         dprintk(DBGLVL_BUF, "   bufsize     0x%x = %d\n", port->bufsize,
 243                 saa7164_readl(port->bufsize));
 244
 245         dprintk(DBGLVL_BUF, "   buffercount = %d\n", port->hwcfg.buffercount);
 246         dprintk(DBGLVL_BUF, "   bufoffset = 0x%x\n", port->bufoffset);
 247         dprintk(DBGLVL_BUF, "   bufptr32h = 0x%x\n", port->bufptr32h);
 248         dprintk(DBGLVL_BUF, "   bufptr32l = 0x%x\n", port->bufptr32l);
 249
 250         /* Poke the buffers and offsets into PCI space */
 251         mutex_lock(&port->dmaqueue_lock);
 252         list_for_each_safe(c, n, &port->dmaqueue.list) {
 253                 buf = list_entry(c, struct saa7164_buffer, list);
 254
 255                 BUG_ON(buf->flags != SAA7164_BUFFER_FREE);
 256
 257                 /* Place the buffer in the h/w queue */
 258                 saa7164_buffer_activate(buf, i);
 259
 260                 /* Don't exceed the device maximum # bufs */
 261                 BUG_ON(i > port->hwcfg.buffercount);
 262                 i++;
 263
 264         }
 265         mutex_unlock(&port->dmaqueue_lock);
 266
 267         return 0;
 268 }
 269
 270 struct saa7164_user_buffer *saa7164_buffer_alloc_user(struct saa7164_dev *dev,
 271         u32 len)
 272 {
 273         struct saa7164_user_buffer *buf;
 274
 275         buf = kzalloc(sizeof(*buf), GFP_KERNEL);
 276         if (!buf)
 277                 return NULL;
 278
 279         buf->data = kzalloc(len, GFP_KERNEL);
 280
 281         if (!buf->data) {
 282                 kfree(buf);
 283                 return NULL;
 284         }
 285
 286         buf->actual_size = len;
 287         buf->pos = 0;
 288         buf->crc = 0;
 289
 290         dprintk(DBGLVL_BUF, "%s()   allocated user buffer @ 0x%p\n",
 291                 __func__, buf);
 292
 293         return buf;
 294 }
 295
 296 void saa7164_buffer_dealloc_user(struct saa7164_user_buffer *buf)
 297 {
 298         if (!buf)
 299                 return;
 300
 301         kfree(buf->data);
 302         buf->data = NULL;
 303
 304         kfree(buf);
 305 }