ARM: Add cpu_architecture() function

Once we run on multiple SoCs we must know which arm architecture we
are on. Add cpu_architecture() from the kernel to detect it.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

2 files changed, 160 insertions, 0 deletions

diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
new file mode 100644
index 0000000000..f39939bd44
--- /dev/null
+++ b/arch/arm/include/asm/cputype.h
@@ -0,0 +1,100 @@
+#ifndef __ASM_ARM_CPUTYPE_H
+#define __ASM_ARM_CPUTYPE_H
+
+#include <linux/stringify.h>
+#include <linux/kernel.h>
+
+#define CPUID_ID	0
+#define CPUID_CACHETYPE	1
+#define CPUID_TCM	2
+#define CPUID_TLBTYPE	3
+#define CPUID_MPIDR	5
+
+#define CPUID_EXT_PFR0	"c1, 0"
+#define CPUID_EXT_PFR1	"c1, 1"
+#define CPUID_EXT_DFR0	"c1, 2"
+#define CPUID_EXT_AFR0	"c1, 3"
+#define CPUID_EXT_MMFR0	"c1, 4"
+#define CPUID_EXT_MMFR1	"c1, 5"
+#define CPUID_EXT_MMFR2	"c1, 6"
+#define CPUID_EXT_MMFR3	"c1, 7"
+#define CPUID_EXT_ISAR0	"c2, 0"
+#define CPUID_EXT_ISAR1	"c2, 1"
+#define CPUID_EXT_ISAR2	"c2, 2"
+#define CPUID_EXT_ISAR3	"c2, 3"
+#define CPUID_EXT_ISAR4	"c2, 4"
+#define CPUID_EXT_ISAR5	"c2, 5"
+
+extern unsigned int processor_id;
+
+#define read_cpuid(reg)							\
+	({								\
+		unsigned int __val;					\
+		asm("mrc	p15, 0, %0, c0, c0, " __stringify(reg)	\
+		    : "=r" (__val)					\
+		    :							\
+		    : "cc");						\
+		__val;							\
+	})
+#define read_cpuid_ext(ext_reg)						\
+	({								\
+		unsigned int __val;					\
+		asm("mrc	p15, 0, %0, c0, " ext_reg		\
+		    : "=r" (__val)					\
+		    :							\
+		    : "cc");						\
+		__val;							\
+	})
+
+/*
+ * The CPU ID never changes at run time, so we might as well tell the
+ * compiler that it's constant.  Use this function to read the CPU ID
+ * rather than directly reading processor_id or read_cpuid() directly.
+ */
+static inline unsigned int __attribute_const__ read_cpuid_id(void)
+{
+	return read_cpuid(CPUID_ID);
+}
+
+static inline unsigned int __attribute_const__ read_cpuid_cachetype(void)
+{
+	return read_cpuid(CPUID_CACHETYPE);
+}
+
+static inline unsigned int __attribute_const__ read_cpuid_tcmstatus(void)
+{
+	return read_cpuid(CPUID_TCM);
+}
+
+static inline unsigned int __attribute_const__ read_cpuid_mpidr(void)
+{
+	return read_cpuid(CPUID_MPIDR);
+}
+
+/*
+ * Intel's XScale3 core supports some v6 features (supersections, L2)
+ * but advertises itself as v5 as it does not support the v6 ISA.  For
+ * this reason, we need a way to explicitly test for this type of CPU.
+ */
+#ifndef CONFIG_CPU_XSC3
+#define cpu_is_xsc3()	0
+#else
+static inline int cpu_is_xsc3(void)
+{
+	unsigned int id;
+	id = read_cpuid_id() & 0xffffe000;
+	/* It covers both Intel ID and Marvell ID */
+	if ((id == 0x69056000) || (id == 0x56056000))
+		return 1;
+
+	return 0;
+}
+#endif
+
+#if !defined(CONFIG_CPU_XSCALE) && !defined(CONFIG_CPU_XSC3)
+#define	cpu_is_xscale()	0
+#else
+#define	cpu_is_xscale()	1
+#endif
+
+#endif
diff --git a/arch/arm/include/asm/system_info.h b/arch/arm/include/asm/system_info.h
new file mode 100644
index 0000000000..5b676313c0
--- /dev/null
+++ b/arch/arm/include/asm/system_info.h
@@ -0,0 +1,60 @@
+#ifndef __ASM_ARM_SYSTEM_INFO_H
+#define __ASM_ARM_SYSTEM_INFO_H
+
+#define CPU_ARCH_UNKNOWN	0
+#define CPU_ARCH_ARMv3		1
+#define CPU_ARCH_ARMv4		2
+#define CPU_ARCH_ARMv4T		3
+#define CPU_ARCH_ARMv5		4
+#define CPU_ARCH_ARMv5T		5
+#define CPU_ARCH_ARMv5TE	6
+#define CPU_ARCH_ARMv5TEJ	7
+#define CPU_ARCH_ARMv6		8
+#define CPU_ARCH_ARMv7		9
+
+#ifdef CONFIG_CPU_32v4T
+#ifdef ARM_ARCH
+#define ARM_MULTIARCH
+#else
+#define ARM_ARCH CPU_ARCH_ARMv4T
+#endif
+#endif
+
+#ifdef CONFIG_CPU_32v5
+#ifdef ARM_ARCH
+#define ARM_MULTIARCH
+#else
+#define ARM_ARCH CPU_ARCH_ARMv5
+#endif
+#endif
+
+#ifdef CONFIG_CPU_32v6
+#ifdef ARM_ARCH
+#define ARM_MULTIARCH
+#else
+#define ARM_ARCH CPU_ARCH_ARMv6
+#endif
+#endif
+
+#ifdef CONFIG_CPU_32v7
+#ifdef ARM_ARCH
+#define ARM_MULTIARCH
+#else
+#define ARM_ARCH CPU_ARCH_ARMv7
+#endif
+#endif
+
+#ifndef __ASSEMBLY__
+
+#ifdef ARM_MULTIARCH
+extern int __pure cpu_architecture(void);
+#else
+static inline int __pure cpu_architecture(void)
+{
+	return ARM_ARCH;
+}
+#endif
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* __ASM_ARM_SYSTEM_INFO_H */