powerpc/dma: use the dma-direct allocator for coherent platforms

The generic code allows a few nice things such as node local allocations
and dipping into the CMA area.  The lookup of the right zone for a given
dma mask works a little different, but the results should be the same.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 5 insertions, 64 deletions

diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c
index a3546a82f6d7..f983f8d435a6 100644
--- a/arch/powerpc/kernel/dma.c
+++ b/arch/powerpc/kernel/dma.c
@@ -27,70 +27,6 @@
  * default the offset is PCI_DRAM_OFFSET.
  */
 
-static u64 __maybe_unused get_pfn_limit(struct device *dev)
-{
-	u64 pfn = (dev->coherent_dma_mask >> PAGE_SHIFT) + 1;
-
-#ifdef CONFIG_SWIOTLB
-	if (dev->bus_dma_mask && dev->dma_ops == &powerpc_swiotlb_dma_ops)
-		pfn = min_t(u64, pfn, dev->bus_dma_mask >> PAGE_SHIFT);
-#endif
-
-	return pfn;
-}
-
-#ifndef CONFIG_NOT_COHERENT_CACHE
-void *__dma_nommu_alloc_coherent(struct device *dev, size_t size,
-				  dma_addr_t *dma_handle, gfp_t flag,
-				  unsigned long attrs)
-{
-	void *ret;
-	struct page *page;
-	int node = dev_to_node(dev);
-#ifdef CONFIG_FSL_SOC
-	u64 pfn = get_pfn_limit(dev);
-	int zone;
-
-	/*
-	 * This code should be OK on other platforms, but we have drivers that
-	 * don't set coherent_dma_mask. As a workaround we just ifdef it. This
-	 * whole routine needs some serious cleanup.
-	 */
-
-	zone = dma_pfn_limit_to_zone(pfn);
-	if (zone < 0) {
-		dev_err(dev, "%s: No suitable zone for pfn %#llx\n",
-			__func__, pfn);
-		return NULL;
-	}
-
-	switch (zone) {
-#ifdef CONFIG_ZONE_DMA
-	case ZONE_DMA:
-		flag |= GFP_DMA;
-		break;
-#endif
-	};
-#endif /* CONFIG_FSL_SOC */
-
-	page = alloc_pages_node(node, flag, get_order(size));
-	if (page == NULL)
-		return NULL;
-	ret = page_address(page);
-	memset(ret, 0, size);
-	*dma_handle = phys_to_dma(dev,__pa(ret));
-
-	return ret;
-}
-
-void __dma_nommu_free_coherent(struct device *dev, size_t size,
-				void *vaddr, dma_addr_t dma_handle,
-				unsigned long attrs)
-{
-	free_pages((unsigned long)vaddr, get_order(size));
-}
-#endif /* !CONFIG_NOT_COHERENT_CACHE */
-
 int dma_nommu_map_sg(struct device *dev, struct scatterlist *sgl,
 		int nents, enum dma_data_direction direction,
 		unsigned long attrs)
@@ -163,8 +99,13 @@ static inline void dma_nommu_sync_single(struct device *dev,
 #endif
 
 const struct dma_map_ops dma_nommu_ops = {
+#ifdef CONFIG_NOT_COHERENT_CACHE
 	.alloc				= __dma_nommu_alloc_coherent,
 	.free				= __dma_nommu_free_coherent,
+#else
+	.alloc				= dma_direct_alloc,
+	.free				= dma_direct_free,
+#endif
 	.map_sg				= dma_nommu_map_sg,
 	.unmap_sg			= dma_nommu_unmap_sg,
 	.dma_supported			= dma_direct_supported,