=================
From 2b476cf741b36da5df35cf2e8f7f9562e8245fcd Mon Sep 17 00:00:00 2001
From: Liu, Jinsong <jinsong.liu@intel.com>
Date: Sun, 9 Oct 2011 22:45:39 +0800
Subject: [PATCH] apic: test tsc deadline timer
Test tsc deadline timer: detect tsc deadline timer support by CPUID,
enable tsc deadline timer mode by MMIO, then start tsc deadline timer by WRMSR.
Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com>
---
x86/apic.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 47 insertions(+), 0 deletions(-)
@@ -25,6 +25,51 @@ static void test_lapic_existence(void)
report("apic existence", (u16)lvr == 0x14);
}
+#define TSC_DEADLINE_TIMER_MODE (2 << 17)
+#define TSC_DEADLINE_TIMER_VECTOR 0xef
+#define MSR_IA32_TSC 0x00000010
+#define MSR_IA32_TSCDEADLINE 0x000006e0
+
+static int tdt_count;
+
+static void tsc_deadline_timer_isr(isr_regs_t *regs)
+{
+ ++tdt_count;
+}
+
+static void start_tsc_deadline_timer(void)
+{
+ handle_irq(TSC_DEADLINE_TIMER_VECTOR, tsc_deadline_timer_isr);
+ irq_enable();
+
+ wrmsr(MSR_IA32_TSCDEADLINE, rdmsr(MSR_IA32_TSC));
+ asm volatile ("nop");
+ report("tsc deadline timer", tdt_count == 1);
+}
+
+static int enable_tsc_deadline_timer(void)
+{
+ uint32_t lvtt;
+
+ if (cpuid(1).c & (1 << 24)) {
+ lvtt = TSC_DEADLINE_TIMER_MODE | TSC_DEADLINE_TIMER_VECTOR;
+ apic_write(APIC_LVTT, lvtt);
+ start_tsc_deadline_timer();
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+static void test_tsc_deadline_timer(void)
+{
+ if(enable_tsc_deadline_timer()) {
+ printf("tsc deadline timer enabled\n");
+ } else {
+ printf("tsc deadline timer not detected\n");
+ }
+}
+
#define MSR_APIC_BASE 0x0000001b
void test_enable_x2apic(void)
@@ -291,6 +336,8 @@ int main()
test_sti_nmi();
test_multiple_nmi();
+ test_tsc_deadline_timer();
+
printf("\nsummary: %d tests, %d failures\n", g_tests, g_fail);
return g_fail != 0;