Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus

[~andy/linux] / arch / mips / mm / dma-default.c

diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c
index f9ef83829a523fd65803b3f5b2c8fdfe77e31a8f..caf92ecb37d6966639c47e6eb277d74cb42f2012 100644 (file)
--- a/arch/mips/mm/dma-default.c
+++ b/arch/mips/mm/dma-default.c
@@ -22,6 +22,26 @@
 
 #include <dma-coherence.h>
 
+int coherentio = 0;    /* User defined DMA coherency from command line. */
+EXPORT_SYMBOL_GPL(coherentio);
+int hw_coherentio = 0; /* Actual hardware supported DMA coherency setting. */
+
+static int __init setcoherentio(char *str)
+{
+       coherentio = 1;
+       pr_info("Hardware DMA cache coherency (command line)\n");
+       return 0;
+}
+early_param("coherentio", setcoherentio);
+
+static int __init setnocoherentio(char *str)
+{
+       coherentio = 0;
+       pr_info("Software DMA cache coherency (command line)\n");
+       return 0;
+}
+early_param("nocoherentio", setnocoherentio);
+
 static inline struct page *dma_addr_to_page(struct device *dev,
        dma_addr_t dma_addr)
 {
@@ -115,7 +135,8 @@ static void *mips_dma_alloc_coherent(struct device *dev, size_t size,
 
                if (!plat_device_is_coherent(dev)) {
                        dma_cache_wback_inv((unsigned long) ret, size);
-                       ret = UNCAC_ADDR(ret);
+                       if (!hw_coherentio)
+                               ret = UNCAC_ADDR(ret);
                }
        }
 
@@ -142,7 +163,7 @@ static void mips_dma_free_coherent(struct device *dev, size_t size, void *vaddr,
 
        plat_unmap_dma_mem(dev, dma_handle, size, DMA_BIDIRECTIONAL);
 
-       if (!plat_device_is_coherent(dev))
+       if (!plat_device_is_coherent(dev) && !hw_coherentio)
                addr = CAC_ADDR(addr);
 
        free_pages(addr, get_order(size));