diff options
author | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-02-06 14:45:32 -0800 |
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committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-02-06 14:45:32 -0800 |
commit | 02aedd69e2ef31b0fca1e8960cb1e7fd0c343110 (patch) | |
tree | c096ab87e0832e8ddda45241b422c0064cfe0cbb /arch/s390/lib/delay.c | |
parent | 9ad0830f307bcd8dc285cfae58998d43b21727f4 (diff) | |
parent | 4d284cac76d0bfebc42d76b428c4e44d921200a9 (diff) |
Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6
* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6: (37 commits)
[S390] Avoid excessive inlining.
[S390] Mark kernel text section read-only.
[S390] Convert memory detection into C code.
[S390] Calibrate delay and bogomips.
[S390] Hypervisor filesystem (s390_hypfs) for z/VM
[S390] Add crypto support for 3592 tape devices
[S390] boot from NSS support
[S390] Support for s390 Pseudo Random Number Generator
[S390] ETR support.
[S390] noexec protection
[S390] move crypto options and some cleanup.
[S390] cio: Don't spam debug feature.
[S390] Cleanup of CHSC event handling.
[S390] cio: declare hardware structures packed.
[S390] Add set_fs(USER_DS) to start_thread().
[S390] cio: Catch operand exceptions on stsch.
[S390] Fix register usage description.
[S390] kretprobe_trampoline_holder() in wrong section.
[S390] Fix kprobes breakpoint handling.
[S390] Update maintainers file.
...
Diffstat (limited to 'arch/s390/lib/delay.c')
-rw-r--r-- | arch/s390/lib/delay.c | 48 |
1 files changed, 34 insertions, 14 deletions
diff --git a/arch/s390/lib/delay.c b/arch/s390/lib/delay.c index 027c4742a00..02854449b74 100644 --- a/arch/s390/lib/delay.c +++ b/arch/s390/lib/delay.c @@ -1,5 +1,5 @@ /* - * arch/s390/kernel/delay.c + * arch/s390/lib/delay.c * Precise Delay Loops for S390 * * S390 version @@ -13,10 +13,8 @@ #include <linux/sched.h> #include <linux/delay.h> - -#ifdef CONFIG_SMP -#include <asm/smp.h> -#endif +#include <linux/timex.h> +#include <linux/irqflags.h> void __delay(unsigned long loops) { @@ -31,17 +29,39 @@ void __delay(unsigned long loops) } /* - * Waits for 'usecs' microseconds using the tod clock, giving up the time slice - * of the virtual PU inbetween to avoid congestion. + * Waits for 'usecs' microseconds using the TOD clock comparator. */ void __udelay(unsigned long usecs) { - uint64_t start_cc; + u64 end, time, jiffy_timer = 0; + unsigned long flags, cr0, mask, dummy; + + local_irq_save(flags); + if (raw_irqs_disabled_flags(flags)) { + jiffy_timer = S390_lowcore.jiffy_timer; + S390_lowcore.jiffy_timer = -1ULL - (4096 << 12); + __ctl_store(cr0, 0, 0); + dummy = (cr0 & 0xffff00e0) | 0x00000800; + __ctl_load(dummy , 0, 0); + mask = psw_kernel_bits | PSW_MASK_WAIT | PSW_MASK_EXT; + } else + mask = psw_kernel_bits | PSW_MASK_WAIT | + PSW_MASK_EXT | PSW_MASK_IO; + + end = get_clock() + ((u64) usecs << 12); + do { + time = end < S390_lowcore.jiffy_timer ? + end : S390_lowcore.jiffy_timer; + set_clock_comparator(time); + trace_hardirqs_on(); + __load_psw_mask(mask); + local_irq_disable(); + } while (get_clock() < end); - if (usecs == 0) - return; - start_cc = get_clock(); - do { - cpu_relax(); - } while (((get_clock() - start_cc)/4096) < usecs); + if (raw_irqs_disabled_flags(flags)) { + __ctl_load(cr0, 0, 0); + S390_lowcore.jiffy_timer = jiffy_timer; + } + set_clock_comparator(S390_lowcore.jiffy_timer); + local_irq_restore(flags); } |