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author | Steven Whitehouse <swhiteho@redhat.com> | 2006-07-03 10:25:08 -0400 |
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committer | Steven Whitehouse <swhiteho@redhat.com> | 2006-07-03 10:25:08 -0400 |
commit | 0a1340c185734a57fbf4775927966ad4a1347b02 (patch) | |
tree | d9ed8f0dd809a7c542a3356601125ea5b5aaa804 /arch/i386/kernel/timers/timer_cyclone.c | |
parent | af18ddb8864b096e3ed4732e2d4b21c956dcfe3a (diff) | |
parent | 29454dde27d8e340bb1987bad9aa504af7081eba (diff) | |
download | lwn-0a1340c185734a57fbf4775927966ad4a1347b02.tar.gz lwn-0a1340c185734a57fbf4775927966ad4a1347b02.zip |
Merge rsync://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:
include/linux/kernel.h
Diffstat (limited to 'arch/i386/kernel/timers/timer_cyclone.c')
-rw-r--r-- | arch/i386/kernel/timers/timer_cyclone.c | 259 |
1 files changed, 0 insertions, 259 deletions
diff --git a/arch/i386/kernel/timers/timer_cyclone.c b/arch/i386/kernel/timers/timer_cyclone.c deleted file mode 100644 index 13892a65c941..000000000000 --- a/arch/i386/kernel/timers/timer_cyclone.c +++ /dev/null @@ -1,259 +0,0 @@ -/* Cyclone-timer: - * This code implements timer_ops for the cyclone counter found - * on IBM x440, x360, and other Summit based systems. - * - * Copyright (C) 2002 IBM, John Stultz (johnstul@us.ibm.com) - */ - - -#include <linux/spinlock.h> -#include <linux/init.h> -#include <linux/timex.h> -#include <linux/errno.h> -#include <linux/string.h> -#include <linux/jiffies.h> - -#include <asm/timer.h> -#include <asm/io.h> -#include <asm/pgtable.h> -#include <asm/fixmap.h> -#include <asm/i8253.h> - -#include "io_ports.h" - -/* Number of usecs that the last interrupt was delayed */ -static int delay_at_last_interrupt; - -#define CYCLONE_CBAR_ADDR 0xFEB00CD0 -#define CYCLONE_PMCC_OFFSET 0x51A0 -#define CYCLONE_MPMC_OFFSET 0x51D0 -#define CYCLONE_MPCS_OFFSET 0x51A8 -#define CYCLONE_TIMER_FREQ 100000000 -#define CYCLONE_TIMER_MASK (((u64)1<<40)-1) /* 40 bit mask */ -int use_cyclone = 0; - -static u32* volatile cyclone_timer; /* Cyclone MPMC0 register */ -static u32 last_cyclone_low; -static u32 last_cyclone_high; -static unsigned long long monotonic_base; -static seqlock_t monotonic_lock = SEQLOCK_UNLOCKED; - -/* helper macro to atomically read both cyclone counter registers */ -#define read_cyclone_counter(low,high) \ - do{ \ - high = cyclone_timer[1]; low = cyclone_timer[0]; \ - } while (high != cyclone_timer[1]); - - -static void mark_offset_cyclone(void) -{ - unsigned long lost, delay; - unsigned long delta = last_cyclone_low; - int count; - unsigned long long this_offset, last_offset; - - write_seqlock(&monotonic_lock); - last_offset = ((unsigned long long)last_cyclone_high<<32)|last_cyclone_low; - - spin_lock(&i8253_lock); - read_cyclone_counter(last_cyclone_low,last_cyclone_high); - - /* read values for delay_at_last_interrupt */ - outb_p(0x00, 0x43); /* latch the count ASAP */ - - count = inb_p(0x40); /* read the latched count */ - count |= inb(0x40) << 8; - - /* - * VIA686a test code... reset the latch if count > max + 1 - * from timer_pit.c - cjb - */ - if (count > LATCH) { - outb_p(0x34, PIT_MODE); - outb_p(LATCH & 0xff, PIT_CH0); - outb(LATCH >> 8, PIT_CH0); - count = LATCH - 1; - } - spin_unlock(&i8253_lock); - - /* lost tick compensation */ - delta = last_cyclone_low - delta; - delta /= (CYCLONE_TIMER_FREQ/1000000); - delta += delay_at_last_interrupt; - lost = delta/(1000000/HZ); - delay = delta%(1000000/HZ); - if (lost >= 2) - jiffies_64 += lost-1; - - /* update the monotonic base value */ - this_offset = ((unsigned long long)last_cyclone_high<<32)|last_cyclone_low; - monotonic_base += (this_offset - last_offset) & CYCLONE_TIMER_MASK; - write_sequnlock(&monotonic_lock); - - /* calculate delay_at_last_interrupt */ - count = ((LATCH-1) - count) * TICK_SIZE; - delay_at_last_interrupt = (count + LATCH/2) / LATCH; - - - /* catch corner case where tick rollover occured - * between cyclone and pit reads (as noted when - * usec delta is > 90% # of usecs/tick) - */ - if (lost && abs(delay - delay_at_last_interrupt) > (900000/HZ)) - jiffies_64++; -} - -static unsigned long get_offset_cyclone(void) -{ - u32 offset; - - if(!cyclone_timer) - return delay_at_last_interrupt; - - /* Read the cyclone timer */ - offset = cyclone_timer[0]; - - /* .. relative to previous jiffy */ - offset = offset - last_cyclone_low; - - /* convert cyclone ticks to microseconds */ - /* XXX slow, can we speed this up? */ - offset = offset/(CYCLONE_TIMER_FREQ/1000000); - - /* our adjusted time offset in microseconds */ - return delay_at_last_interrupt + offset; -} - -static unsigned long long monotonic_clock_cyclone(void) -{ - u32 now_low, now_high; - unsigned long long last_offset, this_offset, base; - unsigned long long ret; - unsigned seq; - - /* atomically read monotonic base & last_offset */ - do { - seq = read_seqbegin(&monotonic_lock); - last_offset = ((unsigned long long)last_cyclone_high<<32)|last_cyclone_low; - base = monotonic_base; - } while (read_seqretry(&monotonic_lock, seq)); - - - /* Read the cyclone counter */ - read_cyclone_counter(now_low,now_high); - this_offset = ((unsigned long long)now_high<<32)|now_low; - - /* convert to nanoseconds */ - ret = base + ((this_offset - last_offset)&CYCLONE_TIMER_MASK); - return ret * (1000000000 / CYCLONE_TIMER_FREQ); -} - -static int __init init_cyclone(char* override) -{ - u32* reg; - u32 base; /* saved cyclone base address */ - u32 pageaddr; /* page that contains cyclone_timer register */ - u32 offset; /* offset from pageaddr to cyclone_timer register */ - int i; - - /* check clock override */ - if (override[0] && strncmp(override,"cyclone",7)) - return -ENODEV; - - /*make sure we're on a summit box*/ - if(!use_cyclone) return -ENODEV; - - printk(KERN_INFO "Summit chipset: Starting Cyclone Counter.\n"); - - /* find base address */ - pageaddr = (CYCLONE_CBAR_ADDR)&PAGE_MASK; - offset = (CYCLONE_CBAR_ADDR)&(~PAGE_MASK); - set_fixmap_nocache(FIX_CYCLONE_TIMER, pageaddr); - reg = (u32*)(fix_to_virt(FIX_CYCLONE_TIMER) + offset); - if(!reg){ - printk(KERN_ERR "Summit chipset: Could not find valid CBAR register.\n"); - return -ENODEV; - } - base = *reg; - if(!base){ - printk(KERN_ERR "Summit chipset: Could not find valid CBAR value.\n"); - return -ENODEV; - } - - /* setup PMCC */ - pageaddr = (base + CYCLONE_PMCC_OFFSET)&PAGE_MASK; - offset = (base + CYCLONE_PMCC_OFFSET)&(~PAGE_MASK); - set_fixmap_nocache(FIX_CYCLONE_TIMER, pageaddr); - reg = (u32*)(fix_to_virt(FIX_CYCLONE_TIMER) + offset); - if(!reg){ - printk(KERN_ERR "Summit chipset: Could not find valid PMCC register.\n"); - return -ENODEV; - } - reg[0] = 0x00000001; - - /* setup MPCS */ - pageaddr = (base + CYCLONE_MPCS_OFFSET)&PAGE_MASK; - offset = (base + CYCLONE_MPCS_OFFSET)&(~PAGE_MASK); - set_fixmap_nocache(FIX_CYCLONE_TIMER, pageaddr); - reg = (u32*)(fix_to_virt(FIX_CYCLONE_TIMER) + offset); - if(!reg){ - printk(KERN_ERR "Summit chipset: Could not find valid MPCS register.\n"); - return -ENODEV; - } - reg[0] = 0x00000001; - - /* map in cyclone_timer */ - pageaddr = (base + CYCLONE_MPMC_OFFSET)&PAGE_MASK; - offset = (base + CYCLONE_MPMC_OFFSET)&(~PAGE_MASK); - set_fixmap_nocache(FIX_CYCLONE_TIMER, pageaddr); - cyclone_timer = (u32*)(fix_to_virt(FIX_CYCLONE_TIMER) + offset); - if(!cyclone_timer){ - printk(KERN_ERR "Summit chipset: Could not find valid MPMC register.\n"); - return -ENODEV; - } - - /*quick test to make sure its ticking*/ - for(i=0; i<3; i++){ - u32 old = cyclone_timer[0]; - int stall = 100; - while(stall--) barrier(); - if(cyclone_timer[0] == old){ - printk(KERN_ERR "Summit chipset: Counter not counting! DISABLED\n"); - cyclone_timer = 0; - return -ENODEV; - } - } - - init_cpu_khz(); - - /* Everything looks good! */ - return 0; -} - - -static void delay_cyclone(unsigned long loops) -{ - unsigned long bclock, now; - if(!cyclone_timer) - return; - bclock = cyclone_timer[0]; - do { - rep_nop(); - now = cyclone_timer[0]; - } while ((now-bclock) < loops); -} -/************************************************************/ - -/* cyclone timer_opts struct */ -static struct timer_opts timer_cyclone = { - .name = "cyclone", - .mark_offset = mark_offset_cyclone, - .get_offset = get_offset_cyclone, - .monotonic_clock = monotonic_clock_cyclone, - .delay = delay_cyclone, -}; - -struct init_timer_opts __initdata timer_cyclone_init = { - .init = init_cyclone, - .opts = &timer_cyclone, -}; |