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 DECLARE_GLOBAL_DATA_PTR;
  20
  21 int dma_get_device(u32 transfer_type, struct udevice **devp)
  22 {
  23         struct udevice *dev;
  24         int ret;
  25
  26         for (ret = uclass_first_device(UCLASS_DMA, &dev); dev && !ret;
  27              ret = uclass_next_device(&dev)) {
  28                 struct dma_dev_priv *uc_priv;
  29
  30                 uc_priv = dev_get_uclass_priv(dev);
  31                 if (uc_priv->supported & transfer_type)
  32                         break;
  33         }
  34
  35         if (!dev) {
  36                 pr_err("No DMA device found that supports %x type\n",
  37                       transfer_type);
  38                 return -EPROTONOSUPPORT;
  39         }
  40
  41         *devp = dev;
  42
  43         return ret;
  44 }
  45
  46 int dma_memcpy(void *dst, void *src, size_t len)
  47 {
  48         struct udevice *dev;
  49         const struct dma_ops *ops;
  50         int ret;
  51
  52         ret = dma_get_device(DMA_SUPPORTS_MEM_TO_MEM, &dev);
  53         if (ret < 0)
  54                 return ret;
  55
  56         ops = device_get_ops(dev);
  57         if (!ops->transfer)
  58                 return -ENOSYS;
  59
  60         /* Invalidate the area, so no writeback into the RAM races with DMA */
  61         invalidate_dcache_range((unsigned long)dst, (unsigned long)dst +
  62                                 roundup(len, ARCH_DMA_MINALIGN));
  63
  64         return ops->transfer(dev, DMA_MEM_TO_MEM, dst, src, len);
  65 }
  66
  67 UCLASS_DRIVER(dma) = {
  68         .id             = UCLASS_DMA,
  69         .name           = "dma",
  70         .flags          = DM_UC_FLAG_SEQ_ALIAS,
  71         .per_device_auto_alloc_size = sizeof(struct dma_dev_priv),
  72 };