drivers/dma/dma-uclass.c

   1 /*
   2  * Direct Memory Access U-Class driver
   3  *
   4  * (C) Copyright 2015
   5  *     Texas Instruments Incorporated, <www.ti.com>
   6  *
   7  * Author: Mugunthan V N <mugunthanvnm@ti.com>
   8  *
   9  * SPDX-License-Identifier:     GPL-2.0+
  10  */
  11
  12 #include <common.h>
  13 #include <dma.h>
  14 #include <dm.h>
  15 #include <dm/uclass-internal.h>
  16 #include <dm/device-internal.h>
  17 #include <errno.h>
  18
  19 int dma_get_device(u32 transfer_type, struct udevice **devp)
  20 {
  21         struct udevice *dev;
  22         int ret;
  23
  24         for (ret = uclass_first_device(UCLASS_DMA, &dev); dev && !ret;
  25              ret = uclass_next_device(&dev)) {
  26                 struct dma_dev_priv *uc_priv;
  27
  28                 uc_priv = dev_get_uclass_priv(dev);
  29                 if (uc_priv->supported & transfer_type)
  30                         break;
  31         }
  32
  33         if (!dev) {
  34                 pr_err("No DMA device found that supports %x type\n",
  35                       transfer_type);
  36                 return -EPROTONOSUPPORT;
  37         }
  38
  39         *devp = dev;
  40
  41         return ret;
  42 }
  43
  44 int dma_memcpy(void *dst, void *src, size_t len)
  45 {
  46         struct udevice *dev;
  47         const struct dma_ops *ops;
  48         int ret;
  49
  50         ret = dma_get_device(DMA_SUPPORTS_MEM_TO_MEM, &dev);
  51         if (ret < 0)
  52                 return ret;
  53
  54         ops = device_get_ops(dev);
  55         if (!ops->transfer)
  56                 return -ENOSYS;
  57
  58         /* Invalidate the area, so no writeback into the RAM races with DMA */
  59         invalidate_dcache_range((unsigned long)dst, (unsigned long)dst +
  60                                 roundup(len, ARCH_DMA_MINALIGN));
  61
  62         return ops->transfer(dev, DMA_MEM_TO_MEM, dst, src, len);
  63 }
  64
  65 UCLASS_DRIVER(dma) = {
  66         .id             = UCLASS_DMA,
  67         .name           = "dma",
  68         .flags          = DM_UC_FLAG_SEQ_ALIAS,
  69         .per_device_auto_alloc_size = sizeof(struct dma_dev_priv),
  70 };