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From b7c1666813424d329868335c8faf8886b0f85b6c Mon Sep 17 00:00:00 2001
From: Greg Ungerer <gerg@linux-m68k.org>
Date: Thu, 11 Aug 2016 21:33:11 +1000
Subject: [PATCH] arm: fix versatile platform to work in no-MMU mode

If CONFIG_MMU is disabled then do not carry out the virtual memory address
translation for IO devices.

With this fix in place we can run the ARM Versatile board (including its
qemu emulation) as a no-MMU Linux system.

Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>

diff -Nur linux-4.4.17.orig/arch/arm/mach-versatile/include/mach/hardware.h linux-4.4.17/arch/arm/mach-versatile/include/mach/hardware.h
--- linux-4.4.17.orig/arch/arm/mach-versatile/include/mach/hardware.h	2016-08-10 11:49:43.000000000 +0200
+++ linux-4.4.17/arch/arm/mach-versatile/include/mach/hardware.h	2016-08-25 23:19:03.691716292 +0200
@@ -30,8 +30,12 @@
 #define VERSATILE_PCI_VIRT_BASE		(void __iomem *)0xe8000000ul
 #define VERSATILE_PCI_CFG_VIRT_BASE	(void __iomem *)0xe9000000ul
 
+#ifdef CONFIG_MMU
 /* macro to get at MMIO space when running virtually */
 #define IO_ADDRESS(x)		(((x) & 0x0fffffff) + (((x) >> 4) & 0x0f000000) + 0xf0000000)
+#else
+#define IO_ADDRESS(x)		(x)
+#endif
 
 #define __io_address(n)		((void __iomem __force *)IO_ADDRESS(n))