MIPS: loongson: remove loongson-3 handling from dma-coherence.h

Loongson3 is dma coherent and uses swiotlb, so it will never used any
of these helpers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Patchwork: https://patchwork.linux-mips.org/patch/19541/
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Tom Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: iommu@lists.linux-foundation.org
Cc: linux-mips@linux-mips.org

arch/mips/include/asm/mach-loongson64/dma-coherence.h

@@ -20,29 +20,19 @@ struct device;
 static inline dma_addr_t plat_map_dma_mem(struct device *dev, void *addr,
 					  size_t size)
 {
-#ifdef CONFIG_CPU_LOONGSON3
-	return __phys_to_dma(dev, virt_to_phys(addr));
-#else
 	return virt_to_phys(addr) | 0x80000000;
-#endif
 }
 
 static inline dma_addr_t plat_map_dma_mem_page(struct device *dev,
 					       struct page *page)
 {
-#ifdef CONFIG_CPU_LOONGSON3
-	return __phys_to_dma(dev, page_to_phys(page));
-#else
 	return page_to_phys(page) | 0x80000000;
-#endif
 }
 
 static inline unsigned long plat_dma_addr_to_phys(struct device *dev,
 	dma_addr_t dma_addr)
 {
-#if defined(CONFIG_CPU_LOONGSON3) && defined(CONFIG_64BIT)
-	return __dma_to_phys(dev, dma_addr);
-#elif defined(CONFIG_CPU_LOONGSON2F) && defined(CONFIG_64BIT)
+#if defined(CONFIG_CPU_LOONGSON2F) && defined(CONFIG_64BIT)
 	return (dma_addr > 0x8fffffff) ? dma_addr : (dma_addr & 0x0fffffff);
 #else
 	return dma_addr & 0x7fffffff;
@@ -69,11 +59,7 @@ static inline int plat_dma_supported(struct device *dev, u64 mask)
 
 static inline int plat_device_is_coherent(struct device *dev)
 {
-#ifdef CONFIG_DMA_NONCOHERENT
 	return 0;
-#else
-	return 1;
-#endif /* CONFIG_DMA_NONCOHERENT */
 }
 
 static inline void plat_post_dma_flush(struct device *dev)