drivers/dma/dma-uclass.c

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