[PATCH 1/3] hvc_dcc: Fix bad code generation by marking assembly volatile
From: Pavel Machek <hidden>
Date: 2011-01-02 09:00:22
Also in:
linux-arm-msm, lkml
Possibly related (same subject, not in this thread)
- 2011-01-03 · Re: [PATCH 1/3] hvc_dcc: Fix bad code generation by marking assembly volatile · Pavel Machek <hidden>
- 2011-01-02 · Re: [PATCH 1/3] hvc_dcc: Fix bad code generation by marking assembly volatile · David Brown <hidden>
Hi!
quoted
diff --git a/drivers/char/hvc_dcc.c b/drivers/char/hvc_dcc.c index 6470f63..155ec10 100644 --- a/drivers/char/hvc_dcc.c +++ b/drivers/char/hvc_dcc.c@@ -33,8 +33,7 @@ static inline u32 __dcc_getstatus(void) { u32 __ret; - - asm("mrc p14, 0, %0, c0, c1, 0 @ read comms ctrl reg" + asm volatile("mrc p14, 0, %0, c0, c1, 0 @ read comms ctrl reg" : "=r" (__ret) : : "cc"); return __ret;
Is volatile needed here? If __dcc_getstatus() return value is discarded, we want assembly discarded, right?
quoted
@@ -58,7 +57,7 @@ static inline char __dcc_getchar(void) { char __c; - asm("mrc p14, 0, %0, c0, c5, 0 @ read comms data reg" + asm volatile("mrc p14, 0, %0, c0, c5, 0 @ read comms data reg" : "=r" (__c)); return __c;
Same here? Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html