From ca9cda2f7b53da619fabde4c0c1bd5f61039bd5b Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Wed, 5 Mar 2008 15:15:42 +0100 Subject: [PATCH] x86: add comments to processor.h add comments to the FPU structures of processor.h. Signed-off-by: Ingo Molnar --- include/asm-x86/processor.h | 51 ++++++++++++++++++++----------------- 1 file changed, 28 insertions(+), 23 deletions(-) diff --git a/include/asm-x86/processor.h b/include/asm-x86/processor.h index e49e5e69ebb0..1f9501a38493 100644 --- a/include/asm-x86/processor.h +++ b/include/asm-x86/processor.h @@ -289,42 +289,47 @@ struct orig_ist { #define MXCSR_DEFAULT 0x1f80 struct i387_fsave_struct { - u32 cwd; - u32 swd; - u32 twd; - u32 fip; - u32 fcs; - u32 foo; - u32 fos; - /* 8*10 bytes for each FP-reg = 80 bytes: */ + u32 cwd; /* FPU Control Word */ + u32 swd; /* FPU Status Word */ + u32 twd; /* FPU Tag Word */ + u32 fip; /* FPU IP Offset */ + u32 fcs; /* FPU IP Selector */ + u32 foo; /* FPU Operand Pointer Offset */ + u32 fos; /* FPU Operand Pointer Selector */ + + /* 8*10 bytes for each FP-reg = 80 bytes: */ u32 st_space[20]; - /* Software status information: */ + + /* Software status information [not touched by FSAVE ]: */ u32 status; }; struct i387_fxsave_struct { - u16 cwd; - u16 swd; - u16 twd; - u16 fop; + u16 cwd; /* Control Word */ + u16 swd; /* Status Word */ + u16 twd; /* Tag Word */ + u16 fop; /* Last Instruction Opcode */ union { struct { - u64 rip; - u64 rdp; + u64 rip; /* Instruction Pointer */ + u64 rdp; /* Data Pointer */ }; struct { - u32 fip; - u32 fcs; - u32 foo; - u32 fos; + u32 fip; /* FPU IP Offset */ + u32 fcs; /* FPU IP Selector */ + u32 foo; /* FPU Operand Offset */ + u32 fos; /* FPU Operand Selector */ }; }; - u32 mxcsr; - u32 mxcsr_mask; - /* 8*16 bytes for each FP-reg = 128 bytes: */ + u32 mxcsr; /* MXCSR Register State */ + u32 mxcsr_mask; /* MXCSR Mask */ + + /* 8*16 bytes for each FP-reg = 128 bytes: */ u32 st_space[32]; - /* 16*16 bytes for each XMM-reg = 256 bytes: */ + + /* 16*16 bytes for each XMM-reg = 256 bytes: */ u32 xmm_space[64]; + u32 padding[24]; } __attribute__((aligned(16))); -- 2.20.1