diff --git a/arch/mips/alchemy/common/setup.c b/arch/mips/alchemy/common/setup.c
index 2902138b3e0f56f639896c571e5bc87172f74d2f..7faaa6d593a74c119cfe6523e4c3e29009b8116a 100644
--- a/arch/mips/alchemy/common/setup.c
+++ b/arch/mips/alchemy/common/setup.c
@@ -48,17 +48,17 @@ void __init plat_mem_setup(void)
 		clear_c0_config(1 << 19); /* Clear Config[OD] */
 
 	hw_coherentio = 0;
-	coherentio = 1;
+	coherentio = IO_COHERENCE_ENABLED;
 	switch (alchemy_get_cputype()) {
 	case ALCHEMY_CPU_AU1000:
 	case ALCHEMY_CPU_AU1500:
 	case ALCHEMY_CPU_AU1100:
-		coherentio = 0;
+		coherentio = IO_COHERENCE_DISABLED;
 		break;
 	case ALCHEMY_CPU_AU1200:
 		/* Au1200 AB USB does not support coherent memory */
 		if (0 == (read_c0_prid() & PRID_REV_MASK))
-			coherentio = 0;
+			coherentio = IO_COHERENCE_DISABLED;
 		break;
 	}
 
diff --git a/arch/mips/include/asm/dma-coherence.h b/arch/mips/include/asm/dma-coherence.h
index bc5e85d579e607a61420a7c0cd7a1c6b716d8f4c..4fbce79fb57faba49a3d96eeb9eef3d5e0f7a7e5 100644
--- a/arch/mips/include/asm/dma-coherence.h
+++ b/arch/mips/include/asm/dma-coherence.h
@@ -9,14 +9,20 @@
 #ifndef __ASM_DMA_COHERENCE_H
 #define __ASM_DMA_COHERENCE_H
 
+enum coherent_io_user_state {
+	IO_COHERENCE_DEFAULT,
+	IO_COHERENCE_ENABLED,
+	IO_COHERENCE_DISABLED,
+};
+
 #ifdef CONFIG_DMA_MAYBE_COHERENT
-extern int coherentio;
+extern enum coherent_io_user_state coherentio;
 extern int hw_coherentio;
 #else
 #ifdef CONFIG_DMA_COHERENT
-#define coherentio	1
+#define coherentio	IO_COHERENCE_ENABLED
 #else
-#define coherentio	0
+#define coherentio	IO_COHERENCE_DISABLED
 #endif
 #define hw_coherentio	0
 #endif /* CONFIG_DMA_MAYBE_COHERENT */
diff --git a/arch/mips/include/asm/mach-generic/dma-coherence.h b/arch/mips/include/asm/mach-generic/dma-coherence.h
index 0f8a354fd4686dc49cbd6718ef565e9b73786386..8484f82fc7941f9cee73050726eb316c3f90a7b6 100644
--- a/arch/mips/include/asm/mach-generic/dma-coherence.h
+++ b/arch/mips/include/asm/mach-generic/dma-coherence.h
@@ -49,7 +49,15 @@ static inline int plat_dma_supported(struct device *dev, u64 mask)
 
 static inline int plat_device_is_coherent(struct device *dev)
 {
-	return coherentio;
+	switch (coherentio) {
+	default:
+	case IO_COHERENCE_DEFAULT:
+		return hw_coherentio;
+	case IO_COHERENCE_ENABLED:
+		return 1;
+	case IO_COHERENCE_DISABLED:
+		return 0;
+	}
 }
 
 #ifndef plat_post_dma_flush
diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c
index 1fc11184e999e5c00390d87501d1e0b5fa810954..78ac033a0f074e56ee367ace412c153573e13607 100644
--- a/arch/mips/mm/c-r4k.c
+++ b/arch/mips/mm/c-r4k.c
@@ -1935,7 +1935,8 @@ void r4k_cache_init(void)
 	__local_flush_icache_user_range	= local_r4k_flush_icache_user_range;
 
 #if defined(CONFIG_DMA_NONCOHERENT) || defined(CONFIG_DMA_MAYBE_COHERENT)
-	if (coherentio) {
+	if ((coherentio == IO_COHERENCE_ENABLED) ||
+	    ((coherentio == IO_COHERENCE_DEFAULT) && hw_coherentio)) {
 		_dma_cache_wback_inv	= (void *)cache_noop;
 		_dma_cache_wback	= (void *)cache_noop;
 		_dma_cache_inv		= (void *)cache_noop;
diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c
index 755259c54976be17c1e42611fc74b90dd3ebb839..8b86c616823922d7ade6eaa3c63094f6c2bdbc91 100644
--- a/arch/mips/mm/dma-default.c
+++ b/arch/mips/mm/dma-default.c
@@ -25,13 +25,14 @@
 #include <dma-coherence.h>
 
 #ifdef CONFIG_DMA_MAYBE_COHERENT
-int coherentio = 0;	/* User defined DMA coherency from command line. */
+/* User defined DMA coherency from command line. */
+enum coherent_io_user_state coherentio = IO_COHERENCE_DEFAULT;
 EXPORT_SYMBOL_GPL(coherentio);
 int hw_coherentio = 0;	/* Actual hardware supported DMA coherency setting. */
 
 static int __init setcoherentio(char *str)
 {
-	coherentio = 1;
+	coherentio = IO_COHERENCE_ENABLED;
 	pr_info("Hardware DMA cache coherency (command line)\n");
 	return 0;
 }
@@ -39,7 +40,7 @@ early_param("coherentio", setcoherentio);
 
 static int __init setnocoherentio(char *str)
 {
-	coherentio = 0;
+	coherentio = IO_COHERENCE_DISABLED;
 	pr_info("Software DMA cache coherency (command line)\n");
 	return 0;
 }
diff --git a/arch/mips/mti-malta/malta-setup.c b/arch/mips/mti-malta/malta-setup.c
index 7e7364b0501edc33f1746962dc9b3796000d3c69..f1b6074828b125cc0d4b3f32c7f4a5c1e848f96c 100644
--- a/arch/mips/mti-malta/malta-setup.c
+++ b/arch/mips/mti-malta/malta-setup.c
@@ -154,12 +154,12 @@ static void __init plat_setup_iocoherency(void)
 	 * coherency instead.
 	 */
 	if (plat_enable_iocoherency()) {
-		if (coherentio == 0)
+		if (coherentio == IO_COHERENCE_DISABLED)
 			pr_info("Hardware DMA cache coherency disabled\n");
 		else
 			pr_info("Hardware DMA cache coherency enabled\n");
 	} else {
-		if (coherentio == 1)
+		if (coherentio == IO_COHERENCE_ENABLED)
 			pr_info("Hardware DMA cache coherency unsupported, but enabled from command line!\n");
 		else
 			pr_info("Software DMA cache coherency enabled\n");
diff --git a/arch/mips/pci/pci-alchemy.c b/arch/mips/pci/pci-alchemy.c
index c8994c156e2ddad2c0bde912c553f66015c8d757..e99ca7702d8ad81660ab011ae4c990c0fb954f96 100644
--- a/arch/mips/pci/pci-alchemy.c
+++ b/arch/mips/pci/pci-alchemy.c
@@ -429,7 +429,8 @@ static int alchemy_pci_probe(struct platform_device *pdev)
 
 	/* Au1500 revisions older than AD have borked coherent PCI */
 	if ((alchemy_get_cputype() == ALCHEMY_CPU_AU1500) &&
-	    (read_c0_prid() < 0x01030202) && !coherentio) {
+	    (read_c0_prid() < 0x01030202) &&
+	    (coherentio == IO_COHERENCE_DISABLED)) {
 		val = __raw_readl(ctx->regs + PCI_REG_CONFIG);
 		val |= PCI_CONFIG_NC;
 		__raw_writel(val, ctx->regs + PCI_REG_CONFIG);