MIPS: Add a platform hook for swiotlb setup.

This allows platforms that are using the swiotlb to initialize it.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Patchwork: http://patchwork.linux-mips.org/patch/1638/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/bootinfo.h

@@ -125,4 +125,16 @@ extern unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
  */
 extern void plat_mem_setup(void);
 
+#ifdef CONFIG_SWIOTLB
+/*
+ * Optional platform hook to call swiotlb_setup().
+ */
+extern void plat_swiotlb_setup(void);
+
+#else
+
+static inline void plat_swiotlb_setup(void) {}
+
+#endif /* CONFIG_SWIOTLB */
+
 #endif /* _ASM_BOOTINFO_H */

arch/mips/kernel/setup.c

@@ -490,6 +490,7 @@ static void __init arch_mem_init(char **cmdline_p)
 	bootmem_init();
 	device_tree_init();
 	sparse_init();
+	plat_swiotlb_setup();
 	paging_init();
 }