From bb8985586b7a906e116db835c64773b7a7d51663 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 17 Aug 2008 21:05:42 -0400 Subject: x86, um: ... and asm-x86 move Signed-off-by: Al Viro Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/mc146818rtc.h | 104 +++++++++++++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) create mode 100644 arch/x86/include/asm/mc146818rtc.h (limited to 'arch/x86/include/asm/mc146818rtc.h') diff --git a/arch/x86/include/asm/mc146818rtc.h b/arch/x86/include/asm/mc146818rtc.h new file mode 100644 index 000000000000..a995f33176cd --- /dev/null +++ b/arch/x86/include/asm/mc146818rtc.h @@ -0,0 +1,104 @@ +/* + * Machine dependent access functions for RTC registers. + */ +#ifndef ASM_X86__MC146818RTC_H +#define ASM_X86__MC146818RTC_H + +#include +#include +#include +#include + +#ifndef RTC_PORT +#define RTC_PORT(x) (0x70 + (x)) +#define RTC_ALWAYS_BCD 1 /* RTC operates in binary mode */ +#endif + +#if defined(CONFIG_X86_32) && defined(__HAVE_ARCH_CMPXCHG) +/* + * This lock provides nmi access to the CMOS/RTC registers. It has some + * special properties. It is owned by a CPU and stores the index register + * currently being accessed (if owned). The idea here is that it works + * like a normal lock (normally). However, in an NMI, the NMI code will + * first check to see if its CPU owns the lock, meaning that the NMI + * interrupted during the read/write of the device. If it does, it goes ahead + * and performs the access and then restores the index register. If it does + * not, it locks normally. + * + * Note that since we are working with NMIs, we need this lock even in + * a non-SMP machine just to mark that the lock is owned. + * + * This only works with compare-and-swap. There is no other way to + * atomically claim the lock and set the owner. + */ +#include +extern volatile unsigned long cmos_lock; + +/* + * All of these below must be called with interrupts off, preempt + * disabled, etc. + */ + +static inline void lock_cmos(unsigned char reg) +{ + unsigned long new; + new = ((smp_processor_id() + 1) << 8) | reg; + for (;;) { + if (cmos_lock) { + cpu_relax(); + continue; + } + if (__cmpxchg(&cmos_lock, 0, new, sizeof(cmos_lock)) == 0) + return; + } +} + +static inline void unlock_cmos(void) +{ + cmos_lock = 0; +} + +static inline int do_i_have_lock_cmos(void) +{ + return (cmos_lock >> 8) == (smp_processor_id() + 1); +} + +static inline unsigned char current_lock_cmos_reg(void) +{ + return cmos_lock & 0xff; +} + +#define lock_cmos_prefix(reg) \ + do { \ + unsigned long cmos_flags; \ + local_irq_save(cmos_flags); \ + lock_cmos(reg) + +#define lock_cmos_suffix(reg) \ + unlock_cmos(); \ + local_irq_restore(cmos_flags); \ + } while (0) +#else +#define lock_cmos_prefix(reg) do {} while (0) +#define lock_cmos_suffix(reg) do {} while (0) +#define lock_cmos(reg) +#define unlock_cmos() +#define do_i_have_lock_cmos() 0 +#define current_lock_cmos_reg() 0 +#endif + +/* + * The yet supported machines all access the RTC index register via + * an ISA port access but the way to access the date register differs ... + */ +#define CMOS_READ(addr) rtc_cmos_read(addr) +#define CMOS_WRITE(val, addr) rtc_cmos_write(val, addr) +unsigned char rtc_cmos_read(unsigned char addr); +void rtc_cmos_write(unsigned char val, unsigned char addr); + +extern int mach_set_rtc_mmss(unsigned long nowtime); +extern unsigned long mach_get_cmos_time(void); + +#define RTC_IRQ 8 + +#endif /* ASM_X86__MC146818RTC_H */ -- cgit v1.2.2 From 1965aae3c98397aad957412413c07e97b1bd4e64 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Wed, 22 Oct 2008 22:26:29 -0700 Subject: x86: Fix ASM_X86__ header guards Change header guards named "ASM_X86__*" to "_ASM_X86_*" since: a. the double underscore is ugly and pointless. b. no leading underscore violates namespace constraints. Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/mc146818rtc.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/x86/include/asm/mc146818rtc.h') diff --git a/arch/x86/include/asm/mc146818rtc.h b/arch/x86/include/asm/mc146818rtc.h index a995f33176cd..01fdf5674e24 100644 --- a/arch/x86/include/asm/mc146818rtc.h +++ b/arch/x86/include/asm/mc146818rtc.h @@ -1,8 +1,8 @@ /* * Machine dependent access functions for RTC registers. */ -#ifndef ASM_X86__MC146818RTC_H -#define ASM_X86__MC146818RTC_H +#ifndef _ASM_X86_MC146818RTC_H +#define _ASM_X86_MC146818RTC_H #include #include @@ -101,4 +101,4 @@ extern unsigned long mach_get_cmos_time(void); #define RTC_IRQ 8 -#endif /* ASM_X86__MC146818RTC_H */ +#endif /* _ASM_X86_MC146818RTC_H */ -- cgit v1.2.2