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Diffstat (limited to 'arch/x86/kernel/mrst.c')
-rw-r--r--arch/x86/kernel/mrst.c105
1 files changed, 82 insertions, 23 deletions
diff --git a/arch/x86/kernel/mrst.c b/arch/x86/kernel/mrst.c
index 5915e0b33303..79ae68154e87 100644
--- a/arch/x86/kernel/mrst.c
+++ b/arch/x86/kernel/mrst.c
@@ -25,8 +25,34 @@
#include <asm/i8259.h>
#include <asm/apb_timer.h>
+/*
+ * the clockevent devices on Moorestown/Medfield can be APBT or LAPIC clock,
+ * cmdline option x86_mrst_timer can be used to override the configuration
+ * to prefer one or the other.
+ * at runtime, there are basically three timer configurations:
+ * 1. per cpu apbt clock only
+ * 2. per cpu always-on lapic clocks only, this is Penwell/Medfield only
+ * 3. per cpu lapic clock (C3STOP) and one apbt clock, with broadcast.
+ *
+ * by default (without cmdline option), platform code first detects cpu type
+ * to see if we are on lincroft or penwell, then set up both lapic or apbt
+ * clocks accordingly.
+ * i.e. by default, medfield uses configuration #2, moorestown uses #1.
+ * config #3 is supported but not recommended on medfield.
+ *
+ * rating and feature summary:
+ * lapic (with C3STOP) --------- 100
+ * apbt (always-on) ------------ 110
+ * lapic (always-on,ARAT) ------ 150
+ */
+
+__cpuinitdata enum mrst_timer_options mrst_timer_options;
+
static u32 sfi_mtimer_usage[SFI_MTMR_MAX_NUM];
static struct sfi_timer_table_entry sfi_mtimer_array[SFI_MTMR_MAX_NUM];
+enum mrst_cpu_type __mrst_cpu_chip;
+EXPORT_SYMBOL_GPL(__mrst_cpu_chip);
+
int sfi_mtimer_num;
struct sfi_rtc_table_entry sfi_mrtc_array[SFI_MRTC_MAX];
@@ -167,18 +193,6 @@ int __init sfi_parse_mrtc(struct sfi_table_header *table)
return 0;
}
-/*
- * the secondary clock in Moorestown can be APBT or LAPIC clock, default to
- * APBT but cmdline option can also override it.
- */
-static void __cpuinit mrst_setup_secondary_clock(void)
-{
- /* restore default lapic clock if disabled by cmdline */
- if (disable_apbt_percpu)
- return setup_secondary_APIC_clock();
- apbt_setup_secondary_clock();
-}
-
static unsigned long __init mrst_calibrate_tsc(void)
{
unsigned long flags, fast_calibrate;
@@ -195,6 +209,21 @@ static unsigned long __init mrst_calibrate_tsc(void)
void __init mrst_time_init(void)
{
+ switch (mrst_timer_options) {
+ case MRST_TIMER_APBT_ONLY:
+ break;
+ case MRST_TIMER_LAPIC_APBT:
+ x86_init.timers.setup_percpu_clockev = setup_boot_APIC_clock;
+ x86_cpuinit.setup_percpu_clockev = setup_secondary_APIC_clock;
+ break;
+ default:
+ if (!boot_cpu_has(X86_FEATURE_ARAT))
+ break;
+ x86_init.timers.setup_percpu_clockev = setup_boot_APIC_clock;
+ x86_cpuinit.setup_percpu_clockev = setup_secondary_APIC_clock;
+ return;
+ }
+ /* we need at least one APB timer */
sfi_table_parse(SFI_SIG_MTMR, NULL, NULL, sfi_parse_mtmr);
pre_init_apic_IRQ0();
apbt_time_init();
@@ -205,16 +234,21 @@ void __init mrst_rtc_init(void)
sfi_table_parse(SFI_SIG_MRTC, NULL, NULL, sfi_parse_mrtc);
}
-/*
- * if we use per cpu apb timer, the bootclock already setup. if we use lapic
- * timer and one apbt timer for broadcast, we need to set up lapic boot clock.
- */
-static void __init mrst_setup_boot_clock(void)
+void __cpuinit mrst_arch_setup(void)
{
- pr_info("%s: per cpu apbt flag %d \n", __func__, disable_apbt_percpu);
- if (disable_apbt_percpu)
- setup_boot_APIC_clock();
-};
+ if (boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 0x27)
+ __mrst_cpu_chip = MRST_CPU_CHIP_PENWELL;
+ else if (boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 0x26)
+ __mrst_cpu_chip = MRST_CPU_CHIP_LINCROFT;
+ else {
+ pr_err("Unknown Moorestown CPU (%d:%d), default to Lincroft\n",
+ boot_cpu_data.x86, boot_cpu_data.x86_model);
+ __mrst_cpu_chip = MRST_CPU_CHIP_LINCROFT;
+ }
+ pr_debug("Moorestown CPU %s identified\n",
+ (__mrst_cpu_chip == MRST_CPU_CHIP_LINCROFT) ?
+ "Lincroft" : "Penwell");
+}
/* MID systems don't have i8042 controller */
static int mrst_i8042_detect(void)
@@ -232,11 +266,13 @@ void __init x86_mrst_early_setup(void)
x86_init.resources.reserve_resources = x86_init_noop;
x86_init.timers.timer_init = mrst_time_init;
- x86_init.timers.setup_percpu_clockev = mrst_setup_boot_clock;
+ x86_init.timers.setup_percpu_clockev = x86_init_noop;
x86_init.irqs.pre_vector_init = x86_init_noop;
- x86_cpuinit.setup_percpu_clockev = mrst_setup_secondary_clock;
+ x86_init.oem.arch_setup = mrst_arch_setup;
+
+ x86_cpuinit.setup_percpu_clockev = apbt_setup_secondary_clock;
x86_platform.calibrate_tsc = mrst_calibrate_tsc;
x86_platform.i8042_detect = mrst_i8042_detect;
@@ -250,3 +286,26 @@ void __init x86_mrst_early_setup(void)
x86_init.mpparse.get_smp_config = x86_init_uint_noop;
}
+
+/*
+ * if user does not want to use per CPU apb timer, just give it a lower rating
+ * than local apic timer and skip the late per cpu timer init.
+ */
+static inline int __init setup_x86_mrst_timer(char *arg)
+{
+ if (!arg)
+ return -EINVAL;
+
+ if (strcmp("apbt_only", arg) == 0)
+ mrst_timer_options = MRST_TIMER_APBT_ONLY;
+ else if (strcmp("lapic_and_apbt", arg) == 0)
+ mrst_timer_options = MRST_TIMER_LAPIC_APBT;
+ else {
+ pr_warning("X86 MRST timer option %s not recognised"
+ " use x86_mrst_timer=apbt_only or lapic_and_apbt\n",
+ arg);
+ return -EINVAL;
+ }
+ return 0;
+}
+__setup("x86_mrst_timer=", setup_x86_mrst_timer);