OpenCores
URL https://opencores.org/ocsvn/or1k_soc_on_altera_embedded_dev_kit/or1k_soc_on_altera_embedded_dev_kit/trunk

Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

[/] [or1k_soc_on_altera_embedded_dev_kit/] [trunk/] [linux-2.6/] [linux-2.6.24/] [arch/] [x86/] [kernel/] [i387_64.c] - Blame information for rev 3

Details | Compare with Previous | View Log

Line No. Rev Author Line
1 3 xianfeng 
/*
2 
 *  Copyright (C) 1994 Linus Torvalds
3 
 *  Copyright (C) 2002 Andi Kleen, SuSE Labs
4 
 *
5 
 *  Pentium III FXSR, SSE support
6 
 *  General FPU state handling cleanups
7 
 *      Gareth Hughes <gareth@valinux.com>, May 2000
8 
 *
9 
 *  x86-64 rework 2002 Andi Kleen.
10 
 *  Does direct fxsave in and out of user space now for signal handlers.
11 
 *  All the FSAVE<->FXSAVE conversion code has been moved to the 32bit emulation,
12 
 *  the 64bit user space sees a FXSAVE frame directly.
13 
 */
14 
 
15 
#include <linux/sched.h>
16 
#include <linux/init.h>
17 
#include <asm/processor.h>
18 
#include <asm/i387.h>
19 
#include <asm/sigcontext.h>
20 
#include <asm/user.h>
21 
#include <asm/ptrace.h>
22 
#include <asm/uaccess.h>
23 
 
24 
unsigned int mxcsr_feature_mask __read_mostly = 0xffffffff;
25 
 
26 
void mxcsr_feature_mask_init(void)
27 
{
28 
        unsigned int mask;
29 
        clts();
30 
        memset(&current->thread.i387.fxsave, 0, sizeof(struct i387_fxsave_struct));
31 
        asm volatile("fxsave %0" : : "m" (current->thread.i387.fxsave));
32 
        mask = current->thread.i387.fxsave.mxcsr_mask;
33 
        if (mask == 0) mask = 0x0000ffbf;
34 
        mxcsr_feature_mask &= mask;
35 
        stts();
36 
}
37 
 
38 
/*
39 
 * Called at bootup to set up the initial FPU state that is later cloned
40 
 * into all processes.
41 
 */
42 
void __cpuinit fpu_init(void)
43 
{
44 
        unsigned long oldcr0 = read_cr0();
45 
        extern void __bad_fxsave_alignment(void);
46 
 
47 
        if (offsetof(struct task_struct, thread.i387.fxsave) & 15)
48 
                __bad_fxsave_alignment();
49 
        set_in_cr4(X86_CR4_OSFXSR);
50 
        set_in_cr4(X86_CR4_OSXMMEXCPT);
51 
 
52 
        write_cr0(oldcr0 & ~((1UL<<3)|(1UL<<2))); /* clear TS and EM */
53 
 
54 
        mxcsr_feature_mask_init();
55 
        /* clean state in init */
56 
        current_thread_info()->status = 0;
57 
        clear_used_math();
58 
}
59 
 
60 
void init_fpu(struct task_struct *child)
61 
{
62 
        if (tsk_used_math(child)) {
63 
                if (child == current)
64 
                        unlazy_fpu(child);
65 
                return;
66 
        }
67 
        memset(&child->thread.i387.fxsave, 0, sizeof(struct i387_fxsave_struct));
68 
        child->thread.i387.fxsave.cwd = 0x37f;
69 
        child->thread.i387.fxsave.mxcsr = 0x1f80;
70 
        /* only the device not available exception or ptrace can call init_fpu */
71 
        set_stopped_child_used_math(child);
72 
}
73 
 
74 
/*
75 
 * Signal frame handlers.
76 
 */
77 
 
78 
int save_i387(struct _fpstate __user *buf)
79 
{
80 
        struct task_struct *tsk = current;
81 
        int err = 0;
82 
 
83 
        BUILD_BUG_ON(sizeof(struct user_i387_struct) !=
84 
                        sizeof(tsk->thread.i387.fxsave));
85 
 
86 
        if ((unsigned long)buf % 16)
87 
                printk("save_i387: bad fpstate %p\n",buf);
88 
 
89 
        if (!used_math())
90 
                return 0;
91 
        clear_used_math(); /* trigger finit */
92 
        if (task_thread_info(tsk)->status & TS_USEDFPU) {
93 
                err = save_i387_checking((struct i387_fxsave_struct __user *)buf);
94 
                if (err) return err;
95 
                task_thread_info(tsk)->status &= ~TS_USEDFPU;
96 
                stts();
97 
        } else {
98 
                if (__copy_to_user(buf, &tsk->thread.i387.fxsave,
99 
                                   sizeof(struct i387_fxsave_struct)))
100 
                        return -1;
101 
        }
102 
        return 1;
103 
}
104 
 
105 
/*
106 
 * ptrace request handlers.
107 
 */
108 
 
109 
int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *tsk)
110 
{
111 
        init_fpu(tsk);
112 
        return __copy_to_user(buf, &tsk->thread.i387.fxsave,
113 
                               sizeof(struct user_i387_struct)) ? -EFAULT : 0;
114 
}
115 
 
116 
int set_fpregs(struct task_struct *tsk, struct user_i387_struct __user *buf)
117 
{
118 
        if (__copy_from_user(&tsk->thread.i387.fxsave, buf,
119 
                             sizeof(struct user_i387_struct)))
120 
                return -EFAULT;
121 
                return 0;
122 
}
123 
 
124 
/*
125 
 * FPU state for core dumps.
126 
 */
127 
 
128 
int dump_fpu( struct pt_regs *regs, struct user_i387_struct *fpu )
129 
{
130 
        struct task_struct *tsk = current;
131 
 
132 
        if (!used_math())
133 
                return 0;
134 
 
135 
        unlazy_fpu(tsk);
136 
        memcpy(fpu, &tsk->thread.i387.fxsave, sizeof(struct user_i387_struct));
137 
        return 1;
138 
}
139 
 
140 
int dump_task_fpu(struct task_struct *tsk, struct user_i387_struct *fpu)
141 
{
142 
        int fpvalid = !!tsk_used_math(tsk);
143 
 
144 
        if (fpvalid) {
145 
                if (tsk == current)
146 
                        unlazy_fpu(tsk);
147 
                memcpy(fpu, &tsk->thread.i387.fxsave, sizeof(struct user_i387_struct));
148 
}
149 
        return fpvalid;
150 
}

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.