| // Basic x86 asm functions. |
| #ifndef __X86_H |
| #define __X86_H |
| |
| // CPU flag bitdefs |
| #define F_CF (1<<0) |
| #define F_ZF (1<<6) |
| #define F_IF (1<<9) |
| #define F_ID (1<<21) |
| |
| // CR0 flags |
| #define CR0_PG (1<<31) // Paging |
| #define CR0_CD (1<<30) // Cache disable |
| #define CR0_NW (1<<29) // Not Write-through |
| #define CR0_PE (1<<0) // Protection enable |
| |
| // PORT_A20 bitdefs |
| #define PORT_A20 0x0092 |
| #define A20_ENABLE_BIT 0x02 |
| |
| #ifndef __ASSEMBLY__ |
| |
| #include "types.h" // u32 |
| |
| static inline void irq_disable(void) |
| { |
| asm volatile("cli": : :"memory"); |
| } |
| |
| static inline void irq_enable(void) |
| { |
| asm volatile("sti": : :"memory"); |
| } |
| |
| static inline u32 save_flags(void) |
| { |
| u32 flags; |
| asm volatile("pushfl ; popl %0" : "=rm" (flags)); |
| return flags; |
| } |
| |
| static inline void restore_flags(u32 flags) |
| { |
| asm volatile("pushl %0 ; popfl" : : "g" (flags) : "memory", "cc"); |
| } |
| |
| static inline void cpu_relax(void) |
| { |
| asm volatile("rep ; nop": : :"memory"); |
| } |
| |
| static inline void nop(void) |
| { |
| asm volatile("nop"); |
| } |
| |
| static inline void hlt(void) |
| { |
| asm volatile("hlt": : :"memory"); |
| } |
| |
| static inline void wbinvd(void) |
| { |
| asm volatile("wbinvd": : :"memory"); |
| } |
| |
| #define CPUID_TSC (1 << 4) |
| #define CPUID_MSR (1 << 5) |
| #define CPUID_APIC (1 << 9) |
| #define CPUID_MTRR (1 << 12) |
| #define CPUID_X2APIC (1 << 21) |
| static inline void __cpuid(u32 index, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx) |
| { |
| asm("cpuid" |
| : "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx) |
| : "0" (index)); |
| } |
| |
| static inline u32 cr0_read(void) { |
| u32 cr0; |
| asm("movl %%cr0, %0" : "=r"(cr0)); |
| return cr0; |
| } |
| static inline void cr0_write(u32 cr0) { |
| asm("movl %0, %%cr0" : : "r"(cr0)); |
| } |
| static inline void cr0_mask(u32 off, u32 on) { |
| cr0_write((cr0_read() & ~off) | on); |
| } |
| static inline u16 cr0_vm86_read(void) { |
| u16 cr0; |
| asm("smsww %0" : "=r"(cr0)); |
| return cr0; |
| } |
| |
| static inline u64 rdmsr(u32 index) |
| { |
| u64 ret; |
| asm ("rdmsr" : "=A"(ret) : "c"(index)); |
| return ret; |
| } |
| |
| static inline void wrmsr(u32 index, u64 val) |
| { |
| asm volatile ("wrmsr" : : "c"(index), "A"(val)); |
| } |
| |
| static inline u64 rdtscll(void) |
| { |
| u64 val; |
| asm volatile("rdtsc" : "=A" (val)); |
| return val; |
| } |
| |
| static inline u32 __ffs(u32 word) |
| { |
| asm("bsf %1,%0" |
| : "=r" (word) |
| : "rm" (word)); |
| return word; |
| } |
| static inline u32 __fls(u32 word) |
| { |
| asm("bsr %1,%0" |
| : "=r" (word) |
| : "rm" (word)); |
| return word; |
| } |
| |
| static inline u32 getesp(void) { |
| u32 esp; |
| asm("movl %%esp, %0" : "=rm"(esp)); |
| return esp; |
| } |
| |
| static inline u32 rol(u32 val, u16 rol) { |
| u32 res; |
| asm volatile("roll %%cl, %%eax" |
| : "=a" (res) : "a" (val), "c" (rol)); |
| return res; |
| } |
| |
| static inline void outb(u8 value, u16 port) { |
| __asm__ __volatile__("outb %b0, %w1" : : "a"(value), "Nd"(port)); |
| } |
| static inline void outw(u16 value, u16 port) { |
| __asm__ __volatile__("outw %w0, %w1" : : "a"(value), "Nd"(port)); |
| } |
| static inline void outl(u32 value, u16 port) { |
| __asm__ __volatile__("outl %0, %w1" : : "a"(value), "Nd"(port)); |
| } |
| static inline u8 inb(u16 port) { |
| u8 value; |
| __asm__ __volatile__("inb %w1, %b0" : "=a"(value) : "Nd"(port)); |
| return value; |
| } |
| static inline u16 inw(u16 port) { |
| u16 value; |
| __asm__ __volatile__("inw %w1, %w0" : "=a"(value) : "Nd"(port)); |
| return value; |
| } |
| static inline u32 inl(u16 port) { |
| u32 value; |
| __asm__ __volatile__("inl %w1, %0" : "=a"(value) : "Nd"(port)); |
| return value; |
| } |
| |
| static inline void insb(u16 port, u8 *data, u32 count) { |
| asm volatile("rep insb (%%dx), %%es:(%%edi)" |
| : "+c"(count), "+D"(data) : "d"(port) : "memory"); |
| } |
| static inline void insw(u16 port, u16 *data, u32 count) { |
| asm volatile("rep insw (%%dx), %%es:(%%edi)" |
| : "+c"(count), "+D"(data) : "d"(port) : "memory"); |
| } |
| static inline void insl(u16 port, u32 *data, u32 count) { |
| asm volatile("rep insl (%%dx), %%es:(%%edi)" |
| : "+c"(count), "+D"(data) : "d"(port) : "memory"); |
| } |
| // XXX - outs not limited to es segment |
| static inline void outsb(u16 port, u8 *data, u32 count) { |
| asm volatile("rep outsb %%es:(%%esi), (%%dx)" |
| : "+c"(count), "+S"(data) : "d"(port) : "memory"); |
| } |
| static inline void outsw(u16 port, u16 *data, u32 count) { |
| asm volatile("rep outsw %%es:(%%esi), (%%dx)" |
| : "+c"(count), "+S"(data) : "d"(port) : "memory"); |
| } |
| static inline void outsl(u16 port, u32 *data, u32 count) { |
| asm volatile("rep outsl %%es:(%%esi), (%%dx)" |
| : "+c"(count), "+S"(data) : "d"(port) : "memory"); |
| } |
| |
| /* Compiler barrier is enough as an x86 CPU does not reorder reads or writes */ |
| static inline void smp_rmb(void) { |
| barrier(); |
| } |
| static inline void smp_wmb(void) { |
| barrier(); |
| } |
| |
| static inline void writel(void *addr, u32 val) { |
| barrier(); |
| *(volatile u32 *)addr = val; |
| } |
| static inline void writew(void *addr, u16 val) { |
| barrier(); |
| *(volatile u16 *)addr = val; |
| } |
| static inline void writeb(void *addr, u8 val) { |
| barrier(); |
| *(volatile u8 *)addr = val; |
| } |
| static inline u32 readl(const void *addr) { |
| u32 val = *(volatile const u32 *)addr; |
| barrier(); |
| return val; |
| } |
| static inline u16 readw(const void *addr) { |
| u16 val = *(volatile const u16 *)addr; |
| barrier(); |
| return val; |
| } |
| static inline u8 readb(const void *addr) { |
| u8 val = *(volatile const u8 *)addr; |
| barrier(); |
| return val; |
| } |
| |
| // GDT bits |
| #define GDT_CODE (0x9bULL << 40) // Code segment - P,R,A bits also set |
| #define GDT_DATA (0x93ULL << 40) // Data segment - W,A bits also set |
| #define GDT_B (0x1ULL << 54) // Big flag |
| #define GDT_G (0x1ULL << 55) // Granularity flag |
| // GDT bits for segment base |
| #define GDT_BASE(v) ((((u64)(v) & 0xff000000) << 32) \ |
| | (((u64)(v) & 0x00ffffff) << 16)) |
| // GDT bits for segment limit (0-1Meg) |
| #define GDT_LIMIT(v) ((((u64)(v) & 0x000f0000) << 32) \ |
| | (((u64)(v) & 0x0000ffff) << 0)) |
| // GDT bits for segment limit (0-4Gig in 4K chunks) |
| #define GDT_GRANLIMIT(v) (GDT_G | GDT_LIMIT((v) >> 12)) |
| |
| struct descloc_s { |
| u16 length; |
| u32 addr; |
| } PACKED; |
| |
| static inline void sgdt(struct descloc_s *desc) { |
| asm("sgdtl %0" : "=m"(*desc)); |
| } |
| static inline void lgdt(struct descloc_s *desc) { |
| asm("lgdtl %0" : : "m"(*desc) : "memory"); |
| } |
| |
| static inline u8 get_a20(void) { |
| return (inb(PORT_A20) & A20_ENABLE_BIT) != 0; |
| } |
| |
| static inline u8 set_a20(u8 cond) { |
| u8 val = inb(PORT_A20), a20_enabled = (val & A20_ENABLE_BIT) != 0; |
| if (a20_enabled != !!cond) |
| outb(val ^ A20_ENABLE_BIT, PORT_A20); |
| return a20_enabled; |
| } |
| |
| // x86.c |
| void cpuid(u32 index, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx); |
| |
| #endif // !__ASSEMBLY__ |
| |
| #endif // x86.h |