ARM: Add get_cr/set_cr functions

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

1 files changed, 72 insertions, 0 deletions

diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h
new file mode 100644
index 0000000000..77d63054ce
--- /dev/null
+++ b/arch/arm/include/asm/system.h
@@ -0,0 +1,72 @@
+#ifndef __ASM_ARM_SYSTEM_H
+#define __ASM_ARM_SYSTEM_H
+
+#if __LINUX_ARM_ARCH__ >= 7
+#define isb() __asm__ __volatile__ ("isb" : : : "memory")
+#define dsb() __asm__ __volatile__ ("dsb" : : : "memory")
+#define dmb() __asm__ __volatile__ ("dmb" : : : "memory")
+#elif defined(CONFIG_CPU_XSC3) || __LINUX_ARM_ARCH__ == 6
+#define isb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c5, 4" \
+                                    : : "r" (0) : "memory")
+#define dsb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
+                                    : : "r" (0) : "memory")
+#define dmb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5" \
+                                    : : "r" (0) : "memory")
+#elif defined(CONFIG_CPU_FA526)
+#define isb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c5, 4" \
+                                    : : "r" (0) : "memory")
+#define dsb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
+                                    : : "r" (0) : "memory")
+#define dmb() __asm__ __volatile__ ("" : : : "memory")
+#else
+#define isb() __asm__ __volatile__ ("" : : : "memory")
+#define dsb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
+                                    : : "r" (0) : "memory")
+#define dmb() __asm__ __volatile__ ("" : : : "memory")
+#endif
+
+/*
+ * CR1 bits (CP#15 CR1)
+ */
+#define CR_M    (1 << 0)	/* MMU enable				*/
+#define CR_A    (1 << 1)	/* Alignment abort enable		*/
+#define CR_C    (1 << 2)	/* Dcache enable			*/
+#define CR_W    (1 << 3)	/* Write buffer enable			*/
+#define CR_P    (1 << 4)	/* 32-bit exception handler		*/
+#define CR_D    (1 << 5)	/* 32-bit data address range		*/
+#define CR_L    (1 << 6)	/* Implementation defined		*/
+#define CR_B    (1 << 7)	/* Big endian				*/
+#define CR_S    (1 << 8)	/* System MMU protection		*/
+#define CR_R    (1 << 9)	/* ROM MMU protection			*/
+#define CR_F    (1 << 10)	/* Implementation defined		*/
+#define CR_Z    (1 << 11)	/* Implementation defined		*/
+#define CR_I    (1 << 12)	/* Icache enable			*/
+#define CR_V    (1 << 13)	/* Vectors relocated to 0xffff0000	*/
+#define CR_RR   (1 << 14)	/* Round Robin cache replacement	*/
+#define CR_L4   (1 << 15)	/* LDR pc can set T bit			*/
+#define CR_DT   (1 << 16)
+#define CR_IT   (1 << 18)
+#define CR_ST   (1 << 19)
+#define CR_FI   (1 << 21)	/* Fast interrupt (lower latency mode)	*/
+#define CR_U    (1 << 22)	/* Unaligned access operation		*/
+#define CR_XP   (1 << 23)	/* Extended page tables			*/
+#define CR_VE   (1 << 24)	/* Vectored interrupts			*/
+#define CR_EE   (1 << 25)	/* Exception (Big) Endian		*/
+#define CR_TRE  (1 << 28)	/* TEX remap enable			*/
+#define CR_AFE  (1 << 29)	/* Access flag enable			*/
+#define CR_TE   (1 << 30)	/* Thumb exception enable		*/
+
+static inline unsigned int get_cr(void)
+{
+	unsigned int val;
+	asm("mrc p15, 0, %0, c1, c0, 0  @ get CR" : "=r" (val) : : "cc");
+	return val;
+}
+
+static inline void set_cr(unsigned int val)
+{
+	asm volatile("mcr p15, 0, %0, c1, c0, 0 @ set CR"
+	  : : "r" (val) : "cc");
+	isb();
+}
+#endif /* __ASM_ARM_SYSTEM_H */