diff options
| author | Eli Billauer <eli.billauer@gmail.com> | 2013-12-30 23:16:25 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-01-09 10:42:36 -0800 |
| commit | cc212550eed155d99e1d4b3e0cfa3510a3d9f9af (patch) | |
| tree | a48a60af69bd10009cc8664debdbd73035e44c00 /drivers/staging/xillybus | |
| parent | 24b33c909ec9096c0613ae30aedd2b4ba2e89efa (diff) | |
staging: xillybus: Open Firmware driver supporting coherent DMA
If the "dma-coherent" property is present in the device tree, the driver will
not perform cache invalidations. This feature significantly improves data
throughput and reduces CPU load.
Signed-off-by: Eli Billauer <eli.billauer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/xillybus')
| -rw-r--r-- | drivers/staging/xillybus/xillybus_of.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/drivers/staging/xillybus/xillybus_of.c b/drivers/staging/xillybus/xillybus_of.c index be124406d711..23a609b0ab1d 100644 --- a/drivers/staging/xillybus/xillybus_of.c +++ b/drivers/staging/xillybus/xillybus_of.c @@ -54,6 +54,13 @@ static void xilly_dma_sync_single_for_device_of(struct xilly_endpoint *ep, dma_sync_single_for_device(ep->dev, dma_handle, size, direction); } +static void xilly_dma_sync_single_nop(struct xilly_endpoint *ep, + dma_addr_t dma_handle, + size_t size, + int direction) +{ +} + static dma_addr_t xilly_map_single_of(struct xilly_cleanup *mem, struct xilly_endpoint *ep, void *ptr, @@ -102,14 +109,26 @@ static struct xilly_endpoint_hardware of_hw = { .unmap_single = xilly_unmap_single_of }; +static struct xilly_endpoint_hardware of_hw_coherent = { + .owner = THIS_MODULE, + .hw_sync_sgl_for_cpu = xilly_dma_sync_single_nop, + .hw_sync_sgl_for_device = xilly_dma_sync_single_nop, + .map_single = xilly_map_single_of, + .unmap_single = xilly_unmap_single_of +}; + static int xilly_drv_probe(struct platform_device *op) { struct device *dev = &op->dev; struct xilly_endpoint *endpoint; int rc = 0; int irq; + struct xilly_endpoint_hardware *ephw = &of_hw; + + if (of_property_read_bool(dev->of_node, "dma-coherent")) + ephw = &of_hw_coherent; - endpoint = xillybus_init_endpoint(NULL, dev, &of_hw); + endpoint = xillybus_init_endpoint(NULL, dev, ephw); if (!endpoint) return -ENOMEM; |