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    Subject[patch 3/9] Remove the support for the VXTIME_HPET timer mode
    VXTIME_HPET will be replaced by a more generic "Master Timer"

    Signed-off-by: Jiri Bohac <jbohac@suse.cz>
    Index: linux-2.6.20-rc5/arch/x86_64/kernel/time.c
    ===================================================================
    --- linux-2.6.20-rc5.orig/arch/x86_64/kernel/time.c
    +++ linux-2.6.20-rc5/arch/x86_64/kernel/time.c
    @@ -101,13 +101,6 @@ static inline unsigned int do_gettimeoff
    return x;
    }

    -static inline unsigned int do_gettimeoffset_hpet(void)
    -{
    - /* cap counter read to one tick to avoid inconsistencies */
    - unsigned long counter = hpet_readl(HPET_COUNTER) - vxtime.last;
    - return (min(counter,hpet_tick) * vxtime.quot) >> US_SCALE;
    -}
    -
    unsigned int (*do_gettimeoffset)(void) = do_gettimeoffset_tsc;

    /*
    @@ -278,17 +271,6 @@ unsigned long long monotonic_clock(void)
    u32 last_offset, this_offset, offset;
    unsigned long long base;

    - if (vxtime.mode == VXTIME_HPET) {
    - do {
    - seq = read_seqbegin(&xtime_lock);
    -
    - last_offset = vxtime.last;
    - base = monotonic_base;
    - this_offset = hpet_readl(HPET_COUNTER);
    - } while (read_seqretry(&xtime_lock, seq));
    - offset = (this_offset - last_offset);
    - offset *= NSEC_PER_TICK / hpet_tick;
    - } else {
    do {
    seq = read_seqbegin(&xtime_lock);

    @@ -297,7 +279,6 @@ unsigned long long monotonic_clock(void)
    } while (read_seqretry(&xtime_lock, seq));
    this_offset = get_cycles_sync();
    offset = cycles_2_ns(this_offset - last_offset);
    - }
    return base + offset;
    }
    EXPORT_SYMBOL(monotonic_clock);
    @@ -316,16 +297,6 @@ static noinline void handle_lost_ticks(i
    KERN_WARNING "Your time source seems to be instable or "
    "some driver is hogging interupts\n");
    print_symbol("rip %s\n", get_irq_regs()->rip);
    - if (vxtime.mode == VXTIME_TSC && vxtime.hpet_address) {
    - printk(KERN_WARNING "Falling back to HPET\n");
    - if (hpet_use_timer)
    - vxtime.last = hpet_readl(HPET_T0_CMP) -
    - hpet_tick;
    - else
    - vxtime.last = hpet_readl(HPET_COUNTER);
    - vxtime.mode = VXTIME_HPET;
    - do_gettimeoffset = do_gettimeoffset_hpet;
    - }
    /* else should fall back to PIT, but code missing. */
    warned = 1;
    } else
    @@ -368,16 +339,6 @@ void main_timer_handler(void)

    tsc = get_cycles_sync();

    - if (vxtime.mode == VXTIME_HPET) {
    - if (offset - vxtime.last > hpet_tick) {
    - lost = (offset - vxtime.last) / hpet_tick - 1;
    - }
    -
    - monotonic_base +=
    - (offset - vxtime.last) * NSEC_PER_TICK / hpet_tick;
    -
    - vxtime.last = offset;
    - } else {
    offset = (((tsc - vxtime.last_tsc) *
    vxtime.tsc_quot) >> US_SCALE) - USEC_PER_TICK;

    @@ -387,7 +348,6 @@ void main_timer_handler(void)
    if (offset > USEC_PER_TICK) {
    lost = offset / USEC_PER_TICK;
    offset %= USEC_PER_TICK;
    - }

    monotonic_base += cycles_2_ns(tsc - vxtime.last_tsc);

    @@ -465,20 +425,6 @@ unsigned long long sched_clock(void)
    {
    unsigned long a = 0;

    -#if 0
    - /* Don't do a HPET read here. Using TSC always is much faster
    - and HPET may not be mapped yet when the scheduler first runs.
    - Disadvantage is a small drift between CPUs in some configurations,
    - but that should be tolerable. */
    - if (__vxtime.mode == VXTIME_HPET)
    - return (hpet_readl(HPET_COUNTER) * vxtime.quot) >> US_SCALE;
    -#endif
    -
    - /* Could do CPU core sync here. Opteron can execute rdtsc speculatively,
    - which means it is not completely exact and may not be monotonous between
    - CPUs. But the errors should be too small to matter for scheduling
    - purposes. */
    -
    rdtscll(a);
    return cycles_2_ns(a);
    }
    @@ -961,18 +907,8 @@ void time_init_gtod(void)
    else
    vgetcpu_mode = VGETCPU_LSL;

    - if (vxtime.hpet_address && notsc) {
    - timetype = hpet_use_timer ? "HPET" : "PIT/HPET";
    - if (hpet_use_timer)
    - vxtime.last = hpet_readl(HPET_T0_CMP) - hpet_tick;
    - else
    - vxtime.last = hpet_readl(HPET_COUNTER);
    - vxtime.mode = VXTIME_HPET;
    - do_gettimeoffset = do_gettimeoffset_hpet;
    - } else {
    timetype = hpet_use_timer ? "HPET/TSC" : "PIT/TSC";
    vxtime.mode = VXTIME_TSC;
    - }

    printk(KERN_INFO "time.c: Using %ld.%06ld MHz WALL %s GTOD %s timer.\n",
    vxtime_hz / 1000000, vxtime_hz % 1000000, timename, timetype);
    @@ -1031,12 +967,6 @@ static int timer_resume(struct sys_devic
    write_seqlock_irqsave(&xtime_lock,flags);
    xtime.tv_sec = sec;
    xtime.tv_nsec = 0;
    - if (vxtime.mode == VXTIME_HPET) {
    - if (hpet_use_timer)
    - vxtime.last = hpet_readl(HPET_T0_CMP) - hpet_tick;
    - else
    - vxtime.last = hpet_readl(HPET_COUNTER);
    - } else
    vxtime.last_tsc = get_cycles_sync();
    write_sequnlock_irqrestore(&xtime_lock,flags);
    jiffies += sleep_length;
    Index: linux-2.6.20-rc5/arch/x86_64/kernel/vsyscall.c
    ===================================================================
    --- linux-2.6.20-rc5.orig/arch/x86_64/kernel/vsyscall.c
    +++ linux-2.6.20-rc5/arch/x86_64/kernel/vsyscall.c
    @@ -72,18 +72,9 @@ static __always_inline void do_vgettimeo
    sec = __xtime.tv_sec;
    usec = __xtime.tv_nsec / 1000;

    - if (__vxtime.mode != VXTIME_HPET) {
    - t = get_cycles_sync();
    - if (t < __vxtime.last_tsc)
    - t = __vxtime.last_tsc;
    - usec += ((t - __vxtime.last_tsc) *
    - __vxtime.tsc_quot) >> 32;
    - /* See comment in x86_64 do_gettimeofday. */
    - } else {
    usec += ((readl((void __iomem *)
    fix_to_virt(VSYSCALL_HPET) + 0xf0) -
    __vxtime.last) * __vxtime.quot) >> 32;
    - }
    } while (read_seqretry(&__xtime_lock, sequence));

    tv->tv_sec = sec + usec / 1000000;
    Index: linux-2.6.20-rc5/include/asm-x86_64/vsyscall.h
    ===================================================================
    --- linux-2.6.20-rc5.orig/include/asm-x86_64/vsyscall.h
    +++ linux-2.6.20-rc5/include/asm-x86_64/vsyscall.h
    @@ -25,7 +25,6 @@ enum vsyscall_num {
    #define __section_xtime_lock __attribute__ ((unused, __section__ (".xtime_lock"), aligned(16)))

    #define VXTIME_TSC 1
    -#define VXTIME_HPET 2

    #define VGETCPU_RDTSCP 1
    #define VGETCPU_LSL 2
    --
    -
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