[PATCH v2 07/28] ARM: KVM: Add system register accessor macros

Marc Zyngier
2016-02-04T11:00:24Z

In order to move system register (CP15, mostly) access to C code,
add a few macros to facilitate this, and minimize the difference
between 32 and 64bit CP15 registers.

This will get heavily used in the following patches.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm/kvm/hyp/hyp.h | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/arch/arm/kvm/hyp/hyp.h b/arch/arm/kvm/hyp/hyp.h
index c723870..727089f 100644
--- a/arch/arm/kvm/hyp/hyp.h
+++ b/arch/arm/kvm/hyp/hyp.h
@@ -27,4 +27,19 @@
#define kern_hyp_va(v) (v)
#define hyp_kern_va(v) (v)

+#define __ACCESS_CP15(CRn, Op1, CRm, Op2) \
+ "mrc", "mcr", __stringify(p15, Op1, %0, CRn, CRm, Op2), u32
+#define __ACCESS_CP15_64(Op1, CRm) \
+ "mrrc", "mcrr", __stringify(p15, Op1, %Q0, %R0, CRm), u64
+
+#define __write_sysreg(v, r, w, c, t) asm volatile(w " " c : : "r" ((t)(v)))
+#define write_sysreg(v, ...) __write_sysreg(v, __VA_ARGS__)
+
+#define __read_sysreg(r, w, c, t) ({ \
+ t __val; \
+ asm volatile(r " " c : "=r" (__val)); \
+ __val; \
+})
+#define read_sysreg(...) __read_sysreg(__VA_ARGS__)
+
#endif /* __ARM_KVM_HYP_H__ */
--
2.1.4