diff options
| author | Russ Anderson <rja@sgi.com> | 2008-07-09 15:27:19 -0500 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-07-18 14:35:14 +0200 |
| commit | 7019cc2dd6fafcdc6b104005482dc910dcdbb797 (patch) | |
| tree | 0f8e67c0b5146543d407dc9f07ace6aeb4b0bd12 /arch/x86/kernel/genx2apic_uv_x.c | |
| parent | 5b664cb235e97afbf34db9c4d77f08ebd725335e (diff) | |
x86 BIOS interface for RTC on SGI UV
Real-time code needs to know the number of cycles per second
on SGI UV. The information is provided via a run time BIOS
call. This patch provides the linux side of that interface.
This is the first of several run time BIOS calls to be defined
in uv/bios.h and bios_uv.c.
Note that BIOS_CALL() is just a stub for now. The bios
side is being worked on.
Signed-off-by: Russ Anderson <rja@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/genx2apic_uv_x.c')
| -rw-r--r-- | arch/x86/kernel/genx2apic_uv_x.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/arch/x86/kernel/genx2apic_uv_x.c b/arch/x86/kernel/genx2apic_uv_x.c index 711f11c30b06..3c3929340692 100644 --- a/arch/x86/kernel/genx2apic_uv_x.c +++ b/arch/x86/kernel/genx2apic_uv_x.c @@ -24,6 +24,7 @@ #include <asm/pgtable.h> #include <asm/uv/uv_mmrs.h> #include <asm/uv/uv_hub.h> +#include <asm/uv/bios.h> DEFINE_PER_CPU(struct uv_hub_info_s, __uv_hub_info); EXPORT_PER_CPU_SYMBOL_GPL(__uv_hub_info); @@ -40,6 +41,9 @@ EXPORT_SYMBOL_GPL(uv_cpu_to_blade); short uv_possible_blades; EXPORT_SYMBOL_GPL(uv_possible_blades); +unsigned long sn_rtc_cycles_per_second; +EXPORT_SYMBOL(sn_rtc_cycles_per_second); + /* Start with all IRQs pointing to boot CPU. IRQ balancing will shift them. */ static cpumask_t uv_target_cpus(void) @@ -272,6 +276,23 @@ static __init void map_mmioh_high(int max_pnode) map_high("MMIOH", mmioh.s.base, shift, map_uc); } +static __init void uv_rtc_init(void) +{ + long status, ticks_per_sec, drift; + + status = + x86_bios_freq_base(BIOS_FREQ_BASE_REALTIME_CLOCK, &ticks_per_sec, + &drift); + if (status != 0 || ticks_per_sec < 100000) { + printk(KERN_WARNING + "unable to determine platform RTC clock frequency, " + "guessing.\n"); + /* BIOS gives wrong value for clock freq. so guess */ + sn_rtc_cycles_per_second = 1000000000000UL / 30000UL; + } else + sn_rtc_cycles_per_second = ticks_per_sec; +} + static __init void uv_system_init(void) { union uvh_si_addr_map_config_u m_n_config; @@ -326,6 +347,8 @@ static __init void uv_system_init(void) gnode_upper = (((unsigned long)node_id.s.node_id) & ~((1 << n_val) - 1)) << m_val; + uv_rtc_init(); + for_each_present_cpu(cpu) { nid = cpu_to_node(cpu); pnode = uv_apicid_to_pnode(per_cpu(x86_cpu_to_apicid, cpu)); |