Some driver want to put DMA buffers in their private data. Add a flag to tell driver model to align driver-private data to a cache boundary so that DMA will work correctly in this case.
Signed-off-by: Simon Glass sjg@chromium.org --- This patch can be dropped once this one is applied:
http://patchwork.ozlabs.org/patch/454670/
Changes in v2: None
drivers/core/device.c | 11 ++++++++++- include/dm/device.h | 3 +++ 2 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/drivers/core/device.c b/drivers/core/device.c index 7483405..872b703 100644 --- a/drivers/core/device.c +++ b/drivers/core/device.c @@ -182,7 +182,16 @@ int device_probe_child(struct udevice *dev, void *parent_priv)
/* Allocate private data if requested */ if (drv->priv_auto_alloc_size) { - dev->priv = calloc(1, drv->priv_auto_alloc_size); + if (drv->flags & DM_FLAG_ALLOC_PRIV_DMA) { + dev->priv = memalign(ARCH_DMA_MINALIGN, + drv->priv_auto_alloc_size); + if (dev->priv) { + memset(dev->priv, '\0', + drv->priv_auto_alloc_size); + } + } else { + dev->priv = calloc(1, drv->priv_auto_alloc_size); + } if (!dev->priv) { ret = -ENOMEM; goto fail; diff --git a/include/dm/device.h b/include/dm/device.h index 6980954..f27b34b 100644 --- a/include/dm/device.h +++ b/include/dm/device.h @@ -30,6 +30,9 @@ struct driver_info; /* DM is responsible for allocating and freeing parent_platdata */ #define DM_FLAG_ALLOC_PARENT_PDATA (1 << 3)
+/* Allocate driver private data on a DMA boundary */ +#define DM_FLAG_ALLOC_PRIV_DMA (1 << 4) + /** * struct udevice - An instance of a driver *