diff options
| -rw-r--r-- | arch/x86/kernel/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/i387.c | 12 | ||||
| -rw-r--r-- | arch/x86/kernel/traps_32.c | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/traps_64.c | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/xsave.c | 87 | ||||
| -rw-r--r-- | include/asm-x86/i387.h | 1 | ||||
| -rw-r--r-- | include/asm-x86/processor-flags.h | 1 | ||||
| -rw-r--r-- | include/asm-x86/processor.h | 12 | ||||
| -rw-r--r-- | include/asm-x86/xsave.h | 26 |
10 files changed, 148 insertions, 6 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index a07ec14f331..d6ea91abaeb 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -38,7 +38,7 @@ obj-y += tsc.o io_delay.o rtc.o obj-$(CONFIG_X86_TRAMPOLINE) += trampoline.o obj-y += process.o -obj-y += i387.o +obj-y += i387.o xsave.o obj-y += ptrace.o obj-y += ds.o obj-$(CONFIG_X86_32) += tls.o diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 80ab20d4fa3..fabbcb7020f 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -712,6 +712,14 @@ void __cpuinit cpu_init(void) current_thread_info()->status = 0; clear_used_math(); mxcsr_feature_mask_init(); + + /* + * Boot processor to setup the FP and extended state context info. + */ + if (!smp_processor_id()) + init_thread_xstate(); + + xsave_init(); } #ifdef CONFIG_HOTPLUG_CPU diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c index eb9ddd8efb8..e22a9a9dce8 100644 --- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -61,6 +61,11 @@ void __init init_thread_xstate(void) return; } + if (cpu_has_xsave) { + xsave_cntxt_init(); + return; + } + if (cpu_has_fxsr) xstate_size = sizeof(struct i387_fxsave_struct); #ifdef CONFIG_X86_32 @@ -83,6 +88,13 @@ void __cpuinit fpu_init(void) write_cr0(oldcr0 & ~(X86_CR0_TS|X86_CR0_EM)); /* clear TS and EM */ + /* + * Boot processor to setup the FP and extended state context info. + */ + if (!smp_processor_id()) + init_thread_xstate(); + xsave_init(); + mxcsr_feature_mask_init(); /* clean state in init */ current_thread_info()->status = 0; diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps_32.c index 03df8e45e5a..da5a5964fcc 100644 --- a/arch/x86/kernel/traps_32.c +++ b/arch/x86/kernel/traps_32.c @@ -1228,7 +1228,6 @@ void __init trap_init(void) set_bit(SYSCALL_VECTOR, used_vectors); - init_thread_xstate(); /* * Should be a barrier for any external CPU state: */ diff --git a/arch/x86/kernel/traps_64.c b/arch/x86/kernel/traps_64.c index 513caaca711..3580a7938a2 100644 --- a/arch/x86/kernel/traps_64.c +++ b/arch/x86/kernel/traps_64.c @@ -1173,10 +1173,6 @@ void __init trap_init(void) set_system_gate(IA32_SYSCALL_VECTOR, ia32_syscall); #endif /* - * initialize the per thread extended state: - */ - init_thread_xstate(); - /* * Should be a barrier for any external CPU state: */ cpu_init(); diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c new file mode 100644 index 00000000000..c68b7c4ca24 --- /dev/null +++ b/arch/x86/kernel/xsave.c @@ -0,0 +1,87 @@ +/* + * xsave/xrstor support. + * + * Author: Suresh Siddha <suresh.b.siddha@intel.com> + */ +#include <linux/bootmem.h> +#include <linux/compat.h> +#include <asm/i387.h> + +/* + * Supported feature mask by the CPU and the kernel. + */ +unsigned int pcntxt_hmask, pcntxt_lmask; + +/* + * Represents init state for the supported extended state. + */ +struct xsave_struct *init_xstate_buf; + +/* + * Enable the extended processor state save/restore feature + */ +void __cpuinit xsave_init(void) +{ + if (!cpu_has_xsave) + return; + + set_in_cr4(X86_CR4_OSXSAVE); + + /* + * Enable all the features that the HW is capable of + * and the Linux kernel is aware of. + * + * xsetbv(); + */ + asm volatile(".byte 0x0f,0x01,0xd1" : : "c" (0), + "a" (pcntxt_lmask), "d" (pcntxt_hmask)); +} + +/* + * setup the xstate image representing the init state + */ +void setup_xstate_init(void) +{ + init_xstate_buf = alloc_bootmem(xstate_size); + init_xstate_buf->i387.mxcsr = MXCSR_DEFAULT; +} + +/* + * Enable and initialize the xsave feature. + */ +void __init xsave_cntxt_init(void) +{ + unsigned int eax, ebx, ecx, edx; + + cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx); + + pcntxt_lmask = eax; + pcntxt_hmask = edx; + + if ((pcntxt_lmask & XSTATE_FPSSE) != XSTATE_FPSSE) { + printk(KERN_ERR "FP/SSE not shown under xsave features %x\n", + pcntxt_lmask); + BUG(); + } + + /* + * for now OS knows only about FP/SSE + */ + pcntxt_lmask = pcntxt_lmask & XCNTXT_LMASK; + pcntxt_hmask = pcntxt_hmask & XCNTXT_HMASK; + + xsave_init(); + + /* + * Recompute the context size for enabled features + */ + cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx); + + xstate_size = ebx; + + setup_xstate_init(); + + printk(KERN_INFO "xsave/xrstor: enabled xstate_bv 0x%Lx, " + "cntxt size 0x%x\n", + (pcntxt_lmask | ((u64) pcntxt_hmask << 32)), xstate_size); +} diff --git a/include/asm-x86/i387.h b/include/asm-x86/i387.h index 3958de6aad0..6a664789667 100644 --- a/include/asm-x86/i387.h +++ b/include/asm-x86/i387.h @@ -18,6 +18,7 @@ #include <asm/sigcontext.h> #include <asm/user.h> #include <asm/uaccess.h> +#include <asm/xsave.h> extern void fpu_init(void); extern void mxcsr_feature_mask_init(void); diff --git a/include/asm-x86/processor-flags.h b/include/asm-x86/processor-flags.h index 5dd79774f69..dc5f0712f9f 100644 --- a/include/asm-x86/processor-flags.h +++ b/include/asm-x86/processor-flags.h @@ -59,6 +59,7 @@ #define X86_CR4_OSFXSR 0x00000200 /* enable fast FPU save and restore */ #define X86_CR4_OSXMMEXCPT 0x00000400 /* enable unmasked SSE exceptions */ #define X86_CR4_VMXE 0x00002000 /* enable VMX virtualization */ +#define X86_CR4_OSXSAVE 0x00040000 /* enable xsave and xrestore */ /* * x86-64 Task Priority Register, CR8 diff --git a/include/asm-x86/processor.h b/include/asm-x86/processor.h index d60b4d81feb..d7c0221c027 100644 --- a/include/asm-x86/processor.h +++ b/include/asm-x86/processor.h @@ -346,6 +346,18 @@ struct i387_soft_struct { u32 entry_eip; }; +struct xsave_hdr_struct { + u64 xstate_bv; + u64 reserved1[2]; + u64 reserved2[5]; +} __attribute__((packed)); + +struct xsave_struct { + struct i387_fxsave_struct i387; + struct xsave_hdr_struct xsave_hdr; + /* new processor state extensions will go here */ +} __attribute__ ((packed, aligned (64))); + union thread_xstate { struct i387_fsave_struct fsave; struct i387_fxsave_struct fxsave; diff --git a/include/asm-x86/xsave.h b/include/asm-x86/xsave.h new file mode 100644 index 00000000000..6d70e62c6bd --- /dev/null +++ b/include/asm-x86/xsave.h @@ -0,0 +1,26 @@ +#ifndef __ASM_X86_XSAVE_H +#define __ASM_X86_XSAVE_H + +#include <asm/processor.h> +#include <asm/i387.h> + +#define XSTATE_FP 0x1 +#define XSTATE_SSE 0x2 + +#define XSTATE_FPSSE (XSTATE_FP | XSTATE_SSE) + +#define FXSAVE_SIZE 512 + +/* + * These are the features that the OS can handle currently. + */ +#define XCNTXT_LMASK (XSTATE_FP | XSTATE_SSE) +#define XCNTXT_HMASK 0x0 + +extern unsigned int xstate_size, pcntxt_hmask, pcntxt_lmask; +extern struct xsave_struct *init_xstate_buf; + +extern void xsave_cntxt_init(void); +extern void xsave_init(void); + +#endif |