[PATCH 3/6] arm64: dcc: simplify accessors

Mark Rutland mark.rutland at arm.com
Thu Sep 8 05:55:36 PDT 2016


A while back we added {read,write}_sysreg accessors to handle accesses
to system registers, without the usual boilerplate asm volatile,
temporary variable, etc.

This patch makes use of these in the arm64 DCC accessors to make the
code shorter and clearer.

Signed-off-by: Mark Rutland <mark.rutland at arm.com>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Will Deacon <will.deacon at arm.com>
---
 arch/arm64/include/asm/dcc.h | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/include/asm/dcc.h b/arch/arm64/include/asm/dcc.h
index 65e0190..836b056 100644
--- a/arch/arm64/include/asm/dcc.h
+++ b/arch/arm64/include/asm/dcc.h
@@ -21,21 +21,16 @@
 #define __ASM_DCC_H
 
 #include <asm/barrier.h>
+#include <asm/sysreg.h>
 
 static inline u32 __dcc_getstatus(void)
 {
-	u32 ret;
-
-	asm volatile("mrs %0, mdccsr_el0" : "=r" (ret));
-
-	return ret;
+	return read_sysreg(mdccsr_el0);
 }
 
 static inline char __dcc_getchar(void)
 {
-	char c;
-
-	asm volatile("mrs %0, dbgdtrrx_el0" : "=r" (c));
+	char c = read_sysreg(dbgdtrrx_el0);
 	isb();
 
 	return c;
@@ -47,8 +42,7 @@ static inline void __dcc_putchar(char c)
 	 * The typecast is to make absolutely certain that 'c' is
 	 * zero-extended.
 	 */
-	asm volatile("msr dbgdtrtx_el0, %0"
-			: : "r" ((unsigned long)(unsigned char)c));
+	write_sysreg((unsigned char)c, dbgdtrtx_el0);
 	isb();
 }
 
-- 
1.9.1




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