From 7019cc2dd6fafcdc6b104005482dc910dcdbb797 Mon Sep 17 00:00:00 2001 From: Russ Anderson Date: Wed, 9 Jul 2008 15:27:19 -0500 Subject: 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 Cc: Jack Steiner Signed-off-by: Ingo Molnar --- arch/x86/kernel/Makefile | 1 + arch/x86/kernel/bios_uv.c | 48 ++++++++++++++++++++++++++++++++++++++++ arch/x86/kernel/genx2apic_uv_x.c | 23 +++++++++++++++++++ 3 files changed, 72 insertions(+) create mode 100644 arch/x86/kernel/bios_uv.c (limited to 'arch') diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index da140611bb5..b78a17b1281 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -102,6 +102,7 @@ obj-$(CONFIG_OLPC) += olpc.o # 64 bit specific files ifeq ($(CONFIG_X86_64),y) obj-y += genapic_64.o genapic_flat_64.o genx2apic_uv_x.o tlb_uv.o + obj-y += bios_uv.o obj-$(CONFIG_X86_PM_TIMER) += pmtimer_64.o obj-$(CONFIG_AUDIT) += audit_64.o diff --git a/arch/x86/kernel/bios_uv.c b/arch/x86/kernel/bios_uv.c new file mode 100644 index 00000000000..c639bd55391 --- /dev/null +++ b/arch/x86/kernel/bios_uv.c @@ -0,0 +1,48 @@ +/* + * BIOS run time interface routines. + * + * Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include + +const char * +x86_bios_strerror(long status) +{ + const char *str; + switch (status) { + case 0: str = "Call completed without error"; break; + case -1: str = "Not implemented"; break; + case -2: str = "Invalid argument"; break; + case -3: str = "Call completed with error"; break; + default: str = "Unknown BIOS status code"; break; + } + return str; +} + +long +x86_bios_freq_base(unsigned long which, unsigned long *ticks_per_second, + unsigned long *drift_info) +{ + struct uv_bios_retval isrv; + + BIOS_CALL(isrv, BIOS_FREQ_BASE, which, 0, 0, 0, 0, 0, 0); + *ticks_per_second = isrv.v0; + *drift_info = isrv.v1; + return isrv.status; +} +EXPORT_SYMBOL_GPL(x86_bios_freq_base); diff --git a/arch/x86/kernel/genx2apic_uv_x.c b/arch/x86/kernel/genx2apic_uv_x.c index 711f11c30b0..3c392934069 100644 --- a/arch/x86/kernel/genx2apic_uv_x.c +++ b/arch/x86/kernel/genx2apic_uv_x.c @@ -24,6 +24,7 @@ #include #include #include +#include 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)); -- cgit v1.2.3