Handle the following architectures in generic flashrom code

- x86/x86_64 (little endian)
- PowerPC (big endian)
- MIPS (big+little endian)

No changes to programmer specific code. This means any drivers with MMIO
access will _not_ suddenly start working on big endian systems, but with
this patch everything is in place to fix them.

Compilation should work on all architectures listed above for all
drivers except nic3com and nicrealtek which require PCI Port IO which is
x86-only for now.

To compile without nic3com and nicrealtek, run
make distclean
make CONFIG_NIC3COM=no CONFIG_NICREALTEK=no

Thanks to Misha Manulis for testing early versions of this patch on
PowerPC (big endian) with the satasii programmer.
Thanks to Segher Boessenkool for design review and for helping out with
compiler tricks and pointing out that we need eieio on PowerPC.
Thanks to Vladimir Serbinenko for compile testing on MIPS (little
endian) and PowerPC (big endian) and for runtime testing on MIPS (little
endian).
Thanks to David Daney for compile testing on MIPS (big endian).
Thanks to Uwe Hermann for compile and runtime testing on x86_64.

DO NOT RUN flashrom ON NON-X86 AFTER APPLYING THIS PATCH!
This patch only provides the infrastructure, but does not convert any
drivers, so flashrom will compile, but it won't do the right thing on
non-x86 platforms.

Corresponding to flashrom svn r1013.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Misha Manulis <misha@manulis.com>
Acked-by: Vladimir 'phcoder/φ-coder' Serbinenko <phcoder@gmail.com>
Acked-by: Uwe Hermann <uwe@hermann-uwe.de>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
diff --git a/hwaccess.c b/hwaccess.c
index 830013e..44d7871 100644
--- a/hwaccess.c
+++ b/hwaccess.c
@@ -26,6 +26,15 @@
 #include <errno.h>
 #include "flash.h"
 
+#if defined(__i386__) || defined(__x86_64__)
+
+/* sync primitive is not needed because x86 uses uncached accesses
+ * which have a strongly ordered memory model.
+ */
+static inline void sync_primitive(void)
+{
+}
+
 #if defined(__FreeBSD__) || defined(__DragonFly__)
 int io_fd;
 #endif
@@ -54,19 +63,68 @@
 #endif
 }
 
+#elif defined(__powerpc__) || defined(__powerpc64__) || defined(__ppc__) || defined(__ppc64__)
+
+static inline void sync_primitive(void)
+{
+	/* Prevent reordering and/or merging of reads/writes to hardware.
+	 * Such reordering and/or merging would break device accesses which
+	 * depend on the exact access order.
+	 */
+	asm("eieio" : : : "memory");
+}
+
+/* PCI port I/O is not yet implemented on PowerPC. */
+void get_io_perms(void)
+{
+}
+
+/* PCI port I/O is not yet implemented on PowerPC. */
+void release_io_perms(void)
+{
+}
+
+#elif defined (__mips) || defined (__mips__) || defined (_mips) || defined (mips)
+
+/* sync primitive is not needed because /dev/mem on MIPS uses uncached accesses
+ * in mode 2 which has a strongly ordered memory model.
+ */
+static inline void sync_primitive(void)
+{
+}
+
+/* PCI port I/O is not yet implemented on MIPS. */
+void get_io_perms(void)
+{
+}
+
+/* PCI port I/O is not yet implemented on MIPS. */
+void release_io_perms(void)
+{
+}
+
+#else
+
+#error Unknown architecture
+
+#endif
+
 void mmio_writeb(uint8_t val, void *addr)
 {
 	*(volatile uint8_t *) addr = val;
+	sync_primitive();
 }
 
 void mmio_writew(uint16_t val, void *addr)
 {
 	*(volatile uint16_t *) addr = val;
+	sync_primitive();
 }
 
 void mmio_writel(uint32_t val, void *addr)
 {
 	*(volatile uint32_t *) addr = val;
+	sync_primitive();
 }
 
 uint8_t mmio_readb(void *addr)
@@ -83,3 +141,33 @@
 {
 	return *(volatile uint32_t *) addr;
 }
+
+void mmio_le_writeb(uint8_t val, void *addr)
+{
+	mmio_writeb(cpu_to_le8(val), addr);
+}
+
+void mmio_le_writew(uint16_t val, void *addr)
+{
+	mmio_writew(cpu_to_le16(val), addr);
+}
+
+void mmio_le_writel(uint32_t val, void *addr)
+{
+	mmio_writel(cpu_to_le32(val), addr);
+}
+
+uint8_t mmio_le_readb(void *addr)
+{
+	return le_to_cpu8(mmio_readb(addr));
+}
+
+uint16_t mmio_le_readw(void *addr)
+{
+	return le_to_cpu16(mmio_readw(addr));
+}
+
+uint32_t mmio_le_readl(void *addr)
+{
+	return le_to_cpu32(mmio_readl(addr));
+}