ARM: vdso: Remove dependency with the arch_timer driver internals

[ Upstream commit 1f5b62f09f6b314c8d70b9de5182dae4de1f94da ]

The VDSO code uses the kernel helper that was originally designed
to abstract the access between 32 and 64bit systems. It worked so
far because this function is declared as 'inline'.

As we're about to revamp that part of the code, the VDSO would
break. Let's fix it by doing what should have been done from
the start, a proper system register access.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/arch/arm/include/asm/cp15.h b/arch/arm/include/asm/cp15.h
index 07e27f212dc754b42b0361536e33ed8bed144f5a..d2453e2d3f1f3804db034c945f268ae614ff3c3f 100644 (file)
--- a/arch/arm/include/asm/cp15.h
+++ b/arch/arm/include/asm/cp15.h
@@ -68,6 +68,8 @@
 #define BPIALL                         __ACCESS_CP15(c7, 0, c5, 6)
 #define ICIALLU                                __ACCESS_CP15(c7, 0, c5, 0)
 
+#define CNTVCT                         __ACCESS_CP15_64(1, c14)
+
 extern unsigned long cr_alignment;     /* defined in entry-armv.S */
 
 static inline unsigned long get_cr(void)

diff --git a/arch/arm/vdso/vgettimeofday.c b/arch/arm/vdso/vgettimeofday.c
index 79214d5ff097044dc59e0394c87749e68d8f4d92..3af02d2a0b7f23008894e1e526d1c11e69931683 100644 (file)
--- a/arch/arm/vdso/vgettimeofday.c
+++ b/arch/arm/vdso/vgettimeofday.c
@@ -18,9 +18,9 @@
 #include <linux/compiler.h>
 #include <linux/hrtimer.h>
 #include <linux/time.h>
-#include <asm/arch_timer.h>
 #include <asm/barrier.h>
 #include <asm/bug.h>
+#include <asm/cp15.h>
 #include <asm/page.h>
 #include <asm/unistd.h>
 #include <asm/vdso_datapage.h>
@@ -123,7 +123,8 @@ static notrace u64 get_ns(struct vdso_data *vdata)
        u64 cycle_now;
        u64 nsec;
 
-       cycle_now = arch_counter_get_cntvct();
+       isb();
+       cycle_now = read_sysreg(CNTVCT);
 
        cycle_delta = (cycle_now - vdata->cs_cycle_last) & vdata->cs_mask;