x86: Provide tick counter and frequency reference for Intel core architecture

[karo-tx-uboot.git] / arch / x86 / cpu / interrupts.c

diff --git a/arch/x86/cpu/interrupts.c b/arch/x86/cpu/interrupts.c
index 89f39d2e363ca064f5db340aff4d4c40d124513e..dd30a05a9ddf54a97d69a62e29aa26c7e3bd0106 100644 (file)
--- a/arch/x86/cpu/interrupts.c
+++ b/arch/x86/cpu/interrupts.c
@@ -28,9 +28,14 @@
  */
 
 #include <common.h>
+#include <asm/cache.h>
+#include <asm/control_regs.h>
 #include <asm/interrupt.h>
 #include <asm/io.h>
 #include <asm/processor-flags.h>
+#include <linux/compiler.h>
+#include <asm/msr.h>
+#include <asm/u-boot-x86.h>
 
 #define DECLARE_INTERRUPT(x) \
        ".globl irq_"#x"\n" \
@@ -40,72 +45,6 @@
        "pushl $"#x"\n" \
        "jmp irq_common_entry\n"
 
-/*
- * Volatile isn't enough to prevent the compiler from reordering the
- * read/write functions for the control registers and messing everything up.
- * A memory clobber would solve the problem, but would prevent reordering of
- * all loads stores around it, which can hurt performance. Solution is to
- * use a variable and mimic reads and writes to it to enforce serialisation
- */
-static unsigned long __force_order;
-
-static inline unsigned long read_cr0(void)
-{
-       unsigned long val;
-       asm volatile("mov %%cr0,%0\n\t" : "=r" (val), "=m" (__force_order));
-       return val;
-}
-
-static inline unsigned long read_cr2(void)
-{
-       unsigned long val;
-       asm volatile("mov %%cr2,%0\n\t" : "=r" (val), "=m" (__force_order));
-       return val;
-}
-
-static inline unsigned long read_cr3(void)
-{
-       unsigned long val;
-       asm volatile("mov %%cr3,%0\n\t" : "=r" (val), "=m" (__force_order));
-       return val;
-}
-
-static inline unsigned long read_cr4(void)
-{
-       unsigned long val;
-       asm volatile("mov %%cr4,%0\n\t" : "=r" (val), "=m" (__force_order));
-       return val;
-}
-
-static inline unsigned long get_debugreg(int regno)
-{
-       unsigned long val = 0;  /* Damn you, gcc! */
-
-       switch (regno) {
-       case 0:
-               asm("mov %%db0, %0" :"=r" (val));
-               break;
-       case 1:
-               asm("mov %%db1, %0" :"=r" (val));
-               break;
-       case 2:
-               asm("mov %%db2, %0" :"=r" (val));
-               break;
-       case 3:
-               asm("mov %%db3, %0" :"=r" (val));
-               break;
-       case 6:
-               asm("mov %%db6, %0" :"=r" (val));
-               break;
-       case 7:
-               asm("mov %%db7, %0" :"=r" (val));
-               break;
-       default:
-               val = 0;
-       }
-       return val;
-}
-
 void dump_regs(struct irq_regs *regs)
 {
        unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L;
@@ -120,7 +59,8 @@ void dump_regs(struct irq_regs *regs)
        printf("ESI: %08lx EDI: %08lx EBP: %08lx ESP: %08lx\n",
                regs->esi, regs->edi, regs->ebp, regs->esp);
        printf(" DS: %04x ES: %04x FS: %04x GS: %04x SS: %04x\n",
-              (u16)regs->xds, (u16)regs->xes, (u16)regs->xfs, (u16)regs->xgs, (u16)regs->xss);
+              (u16)regs->xds, (u16)regs->xes, (u16)regs->xfs,
+              (u16)regs->xgs, (u16)regs->xss);
 
        cr0 = read_cr0();
        cr2 = read_cr2();
@@ -164,21 +104,21 @@ struct idt_entry {
        u8      res;
        u8      access;
        u16     base_high;
-} __attribute__ ((packed));
+} __packed;
 
 struct desc_ptr {
        unsigned short size;
        unsigned long address;
        unsigned short segment;
-} __attribute__((packed));
+} __packed;
 
-struct idt_entry idt[256];
+struct idt_entry idt[256] __aligned(16);
 
 struct desc_ptr idt_ptr;
 
 static inline void load_idt(const struct desc_ptr *dtr)
 {
-       asm volatile("cs lidt %0"::"m" (*dtr));
+       asm volatile("cs lidt %0" : : "m" (*dtr));
 }
 
 void set_vector(u8 intnum, void *routine)
@@ -187,6 +127,11 @@ void set_vector(u8 intnum, void *routine)
        idt[intnum].base_low = (u16)((u32)(routine) & 0xffff);
 }
 
+/*
+ * Ideally these would be defined static to avoid a checkpatch warning, but
+ * the compiler cannot see them in the inline asm and complains that they
+ * aren't defined
+ */
 void irq_0(void);
 void irq_1(void);
 
@@ -201,7 +146,7 @@ int cpu_init_interrupts(void)
        disable_interrupts();
 
        /* Setup the IDT */
-       for (i=0;i<256;i++) {
+       for (i = 0; i < 256; i++) {
                idt[i].access = 0x8e;
                idt[i].res = 0;
                idt[i].selector = 0x10;
@@ -238,7 +183,7 @@ int disable_interrupts(void)
 
        asm volatile ("pushfl ; popl %0 ; cli\n" : "=g" (flags) : );
 
-       return flags & X86_EFLAGS_IF; /* IE flags is bit 9 */
+       return flags & X86_EFLAGS_IF;
 }
 
 /* IRQ Low-Level Service Routine */
@@ -672,3 +617,32 @@ asm(".globl irq_common_entry\n" \
        DECLARE_INTERRUPT(253) \
        DECLARE_INTERRUPT(254) \
        DECLARE_INTERRUPT(255));
+
+#if defined(CONFIG_INTEL_CORE_ARCH)
+/*
+ * Get the number of CPU time counter ticks since it was read first time after
+ * restart. This yields a free running counter guaranteed to take almost 6
+ * years to wrap around even at 100GHz clock rate.
+ */
+u64 get_ticks(void)
+{
+       static u64 tick_base;
+       u64 now_tick = rdtsc();
+
+       if (!tick_base)
+               tick_base = now_tick;
+
+       return now_tick - tick_base;
+}
+
+#define PLATFORM_INFO_MSR 0xce
+
+unsigned long get_tbclk(void)
+{
+       u32 ratio;
+       u64 platform_info = native_read_msr(PLATFORM_INFO_MSR);
+
+       ratio = (platform_info >> 8) & 0xff;
+       return 100 * 1000 * 1000 * ratio; /* 100MHz times Max Non Turbo ratio */
+}
+#endif