[bootwrapper PATCH v3 06/15] aarch32: add coprocessor accessors

Mark Rutland mark.rutland at arm.com
Tue Jan 25 07:00:48 PST 2022


We open code the use of mrc/mcr for specific registers, which is
somewhat tedious. Add macros to do this generically, along with a helper
to extract a specific register field. Existing C usage is converted to
the new helpers, and register definitions moved to a common location.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland at arm.com>
---
 arch/aarch32/include/asm/cpu.h    | 45 ++++++++++++++++++++-----------
 arch/aarch32/include/asm/gic-v3.h |  6 +++--
 2 files changed, 34 insertions(+), 17 deletions(-)

diff --git a/arch/aarch32/include/asm/cpu.h b/arch/aarch32/include/asm/cpu.h
index 105cae5..d691c7b 100644
--- a/arch/aarch32/include/asm/cpu.h
+++ b/arch/aarch32/include/asm/cpu.h
@@ -9,9 +9,13 @@
 #ifndef __ASM_AARCH32_CPU_H
 #define __ASM_AARCH32_CPU_H
 
+#include <bits.h>
+
 #define MPIDR_ID_BITS		0x00ffffff
 #define MPIDR_INVALID		(-1)
 
+#define ID_PFR1_GIC		BITS(31, 28)
+
 /* Only RES1 bits and CP15 barriers for the kernel */
 #define HSCTLR_KERNEL		(3 << 28 | 3 << 22 | 1 << 18 | 1 << 16 | 1 << 11 | 3 << 4)
 #define SCTLR_KERNEL		(3 << 22 | 1 << 11 | 1 << 5 | 3 << 4)
@@ -40,32 +44,43 @@
 #define sevl()		asm volatile ("sev" : : : "memory")
 #endif
 
-static inline unsigned long read_mpidr(void)
-{
-	unsigned long mpidr;
+#define MPIDR		"p15, 0, %0, c0, c0, 5"
+#define ID_PFR1		"p15, 0, %0, c0, c1, 1"
+#define ICIALLU		"p15, 0, %0, c7, c5, 0"
 
-	asm volatile ("mrc	p15, 0, %0, c0, c0, 5\n" : "=r" (mpidr));
-	return mpidr & MPIDR_ID_BITS;
-}
+#define ICC_SRE		"p15, 6, %0, c12, c12, 5"
+#define ICC_CTLR	"p15, 6, %0, c12, c12, 4"
 
-static inline uint32_t read_id_pfr1(void)
-{
-	uint32_t val;
+#define mrc(reg)						\
+({								\
+	unsigned long __mrc_val;				\
+	asm volatile("mrc " reg : "=r" (__mrc_val));		\
+	__mrc_val;						\
+})
 
-	asm volatile ("mrc	p15, 0, %0, c0, c1, 1\n" : "=r" (val));
-	return val;
+#define mcr(reg, val)						\
+do {								\
+	unsigned long __mcr_val = val;				\
+	asm volatile("mcr " reg : : "r" (__mcr_val));		\
+} while (0)
+
+
+#define mrc_field(reg, field) \
+	BITS_EXTRACT(mrc(reg), (reg##_##field))
+
+static inline unsigned long read_mpidr(void)
+{
+	return mrc(MPIDR) & MPIDR_ID_BITS;
 }
 
 static inline void iciallu(void)
 {
-	uint32_t val = 0;
-
-	asm volatile ("mcr	p15, 0, %0, c7, c5, 0" : : "r" (val));
+	mcr(ICIALLU, 0);
 }
 
 static inline int has_gicv3_sysreg(void)
 {
-	return !!((read_id_pfr1() >> 28) & 0xf);
+	return !!mrc_field(ID_PFR1, GIC);
 }
 
 #endif /* __ASSEMBLY__ */
diff --git a/arch/aarch32/include/asm/gic-v3.h b/arch/aarch32/include/asm/gic-v3.h
index 65f38de..b28136a 100644
--- a/arch/aarch32/include/asm/gic-v3.h
+++ b/arch/aarch32/include/asm/gic-v3.h
@@ -9,14 +9,16 @@
 #ifndef __ASM_AARCH32_GICV3_H
 #define __ASM_AARCH32_GICV3_H
 
+#include <asm/cpu.h>
+
 static inline void gic_write_icc_sre(uint32_t val)
 {
-	asm volatile ("mcr p15, 6, %0, c12, c12, 5" : : "r" (val));
+	mcr(ICC_SRE, val);
 }
 
 static inline void gic_write_icc_ctlr(uint32_t val)
 {
-	asm volatile ("mcr p15, 6, %0, c12, c12, 4" : : "r" (val));
+	mcr(ICC_CTLR, val);
 }
 
 #endif
-- 
2.30.2




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