dm: implement a DMA uclass

[u-boot] / drivers / dma / dma-uclass.c

diff --git a/drivers/dma/dma-uclass.c b/drivers/dma/dma-uclass.c
new file mode 100644 (file)
index 0000000..ea21fd9
--- /dev/null
+++ b/drivers/dma/dma-uclass.c
@@ -0,0 +1,72 @@
+/*
+ * Direct Memory Access U-Class driver
+ *
+ * (C) Copyright 2015
+ *     Texas Instruments Incorporated, <www.ti.com>
+ *
+ * Author: Mugunthan V N <mugunthanvnm@ti.com>
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <common.h>
+#include <dma.h>
+#include <dm.h>
+#include <dm/uclass-internal.h>
+#include <dm/device-internal.h>
+#include <errno.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int dma_get_device(u32 transfer_type, struct udevice **devp)
+{
+       struct udevice *dev;
+       int ret;
+
+       for (ret = uclass_first_device(UCLASS_DMA, &dev); dev && !ret;
+            ret = uclass_next_device(&dev)) {
+               struct dma_dev_priv *uc_priv;
+
+               uc_priv = dev_get_uclass_priv(dev);
+               if (uc_priv->supported & transfer_type)
+                       break;
+       }
+
+       if (!dev) {
+               error("No DMA device found that supports %x type\n",
+                     transfer_type);
+               return -EPROTONOSUPPORT;
+       }
+
+       *devp = dev;
+
+       return ret;
+}
+
+int dma_memcpy(void *dst, void *src, size_t len)
+{
+       struct udevice *dev;
+       const struct dma_ops *ops;
+       int ret;
+
+       ret = dma_get_device(DMA_SUPPORTS_MEM_TO_MEM, &dev);
+       if (ret < 0)
+               return ret;
+
+       ops = device_get_ops(dev);
+       if (!ops->transfer)
+               return -ENOSYS;
+
+       /* Invalidate the area, so no writeback into the RAM races with DMA */
+       invalidate_dcache_range((unsigned long)dst, (unsigned long)dst +
+                               roundup(len, ARCH_DMA_MINALIGN));
+
+       return ops->transfer(dev, DMA_MEM_TO_MEM, dst, src, len);
+}
+
+UCLASS_DRIVER(dma) = {
+       .id             = UCLASS_DMA,
+       .name           = "dma",
+       .flags          = DM_UC_FLAG_SEQ_ALIAS,
+       .per_device_auto_alloc_size = sizeof(struct dma_dev_priv),
+};