LXR linux/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
  55void 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 */
  78struct 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
 139fail2:
 140        dma_free_coherent(&port->dev->pci->dev, buf->pci_size, buf->cpu,
 141                          buf->dma);
 142fail1:
 143        kfree(buf);
 144
 145        buf = NULL;
 146ret:
 147        return buf;
 148}
 149
 150int 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
 173int 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 */
 188int 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
 220int 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
 270struct 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
 296void 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}
 306