[PATCH v4 2/6] drm/nouveau: map pages using DMA API on platform devices

From: Alexandre Courbot
Date: Tue Jul 08 2014 - 04:30:55 EST


page_to_phys() is not the correct way to obtain the DMA address of a
buffer on a non-PCI system. Use the DMA API functions for this, which
are portable and will allow us to use other DMA API functions for
buffer synchronization.

Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx>
---
drivers/gpu/drm/nouveau/core/engine/device/base.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/nouveau/core/engine/device/base.c b/drivers/gpu/drm/nouveau/core/engine/device/base.c
index 18c8c7245b73..e4e9e64988fe 100644
--- a/drivers/gpu/drm/nouveau/core/engine/device/base.c
+++ b/drivers/gpu/drm/nouveau/core/engine/device/base.c
@@ -489,7 +489,10 @@ nv_device_map_page(struct nouveau_device *device, struct page *page)
if (pci_dma_mapping_error(device->pdev, ret))
ret = 0;
} else {
- ret = page_to_phys(page);
+ ret = dma_map_page(&device->platformdev->dev, page, 0,
+ PAGE_SIZE, DMA_BIDIRECTIONAL);
+ if (dma_mapping_error(&device->platformdev->dev, ret))
+ ret = 0;
}

return ret;
@@ -501,6 +504,9 @@ nv_device_unmap_page(struct nouveau_device *device, dma_addr_t addr)
if (nv_device_is_pci(device))
pci_unmap_page(device->pdev, addr, PAGE_SIZE,
PCI_DMA_BIDIRECTIONAL);
+ else
+ dma_unmap_page(&device->platformdev->dev, addr,
+ PAGE_SIZE, DMA_BIDIRECTIONAL);
}

int
--
2.0.0

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