[ARM] cputype: separate definitions, use them

Add asm/cputype.h, moving functions and definitions from asm/system.h
there.  Convert all users of 'processor_id' to the more efficient
read_cpuid_id() function.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-ixp4xx/common-pci.c b/arch/arm/mach-ixp4xx/common-pci.c
index 192538a..f74a460 100644
--- a/arch/arm/mach-ixp4xx/common-pci.c
+++ b/arch/arm/mach-ixp4xx/common-pci.c
@@ -27,6 +27,7 @@
 #include <linux/device.h>
 #include <asm/dma-mapping.h>
 
+#include <asm/cputype.h>
 #include <asm/io.h>
 #include <asm/irq.h>
 #include <asm/sizes.h>
@@ -366,15 +367,13 @@
 
 void __init ixp4xx_pci_preinit(void)
 {  
-	unsigned long processor_id;
-
-	asm("mrc p15, 0, %0, cr0, cr0, 0;" : "=r"(processor_id) :);
+	unsigned long cpuid = read_cpuid_id();
 
 	/*
 	 * Determine which PCI read method to use.
 	 * Rev 0 IXP425 requires workaround.
 	 */
-	if (!(processor_id & 0xf) && cpu_is_ixp42x()) {
+	if (!(cpuid & 0xf) && cpu_is_ixp42x()) {
 		printk("PCI: IXP42x A0 silicon detected - "
 			"PCI Non-Prefetch Workaround Enabled\n");
 		ixp4xx_pci_read = ixp4xx_pci_read_errata;
diff --git a/arch/arm/mach-ixp4xx/include/mach/cpu.h b/arch/arm/mach-ixp4xx/include/mach/cpu.h
index ff8aa23..51bd69c 100644
--- a/arch/arm/mach-ixp4xx/include/mach/cpu.h
+++ b/arch/arm/mach-ixp4xx/include/mach/cpu.h
@@ -14,18 +14,19 @@
 #ifndef __ASM_ARCH_CPU_H__
 #define __ASM_ARCH_CPU_H__
 
-extern unsigned int processor_id;
+#include <asm/cputype.h>
+
 /* Processor id value in CP15 Register 0 */
 #define IXP425_PROCESSOR_ID_VALUE	0x690541c0
 #define IXP435_PROCESSOR_ID_VALUE	0x69054040
 #define IXP465_PROCESSOR_ID_VALUE	0x69054200
 #define IXP4XX_PROCESSOR_ID_MASK	0xfffffff0
 
-#define cpu_is_ixp42x()	((processor_id & IXP4XX_PROCESSOR_ID_MASK) == \
+#define cpu_is_ixp42x()	((read_cpuid_id() & IXP4XX_PROCESSOR_ID_MASK) == \
 			  IXP425_PROCESSOR_ID_VALUE)
-#define cpu_is_ixp43x()	((processor_id & IXP4XX_PROCESSOR_ID_MASK) == \
+#define cpu_is_ixp43x()	((read_cpuid_id() & IXP4XX_PROCESSOR_ID_MASK) == \
 			  IXP435_PROCESSOR_ID_VALUE)
-#define cpu_is_ixp46x()	((processor_id & IXP4XX_PROCESSOR_ID_MASK) == \
+#define cpu_is_ixp46x()	((read_cpuid_id() & IXP4XX_PROCESSOR_ID_MASK) == \
 			  IXP465_PROCESSOR_ID_VALUE)
 
 static inline u32 ixp4xx_read_feature_bits(void)