1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
|
/*
* Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
* Copyright (C) 2008-2009 PetaLogix
* Copyright (C) 2006 Atmark Techno, Inc.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/pm.h>
#include <linux/tick.h>
#include <linux/bitops.h>
#include <asm/system.h>
#include <asm/pgalloc.h>
void show_regs(struct pt_regs *regs)
{
printk(KERN_INFO " Registers dump: mode=%X\r\n", regs->pt_mode);
printk(KERN_INFO " r1=%08lX, r2=%08lX, r3=%08lX, r4=%08lX\n",
regs->r1, regs->r2, regs->r3, regs->r4);
printk(KERN_INFO " r5=%08lX, r6=%08lX, r7=%08lX, r8=%08lX\n",
regs->r5, regs->r6, regs->r7, regs->r8);
printk(KERN_INFO " r9=%08lX, r10=%08lX, r11=%08lX, r12=%08lX\n",
regs->r9, regs->r10, regs->r11, regs->r12);
printk(KERN_INFO " r13=%08lX, r14=%08lX, r15=%08lX, r16=%08lX\n",
regs->r13, regs->r14, regs->r15, regs->r16);
printk(KERN_INFO " r17=%08lX, r18=%08lX, r19=%08lX, r20=%08lX\n",
regs->r17, regs->r18, regs->r19, regs->r20);
printk(KERN_INFO " r21=%08lX, r22=%08lX, r23=%08lX, r24=%08lX\n",
regs->r21, regs->r22, regs->r23, regs->r24);
printk(KERN_INFO " r25=%08lX, r26=%08lX, r27=%08lX, r28=%08lX\n",
regs->r25, regs->r26, regs->r27, regs->r28);
printk(KERN_INFO " r29=%08lX, r30=%08lX, r31=%08lX, rPC=%08lX\n",
regs->r29, regs->r30, regs->r31, regs->pc);
printk(KERN_INFO " msr=%08lX, ear=%08lX, esr=%08lX, fsr=%08lX\n",
regs->msr, regs->ear, regs->esr, regs->fsr);
}
void (*pm_idle)(void);
void (*pm_power_off)(void) = NULL;
EXPORT_SYMBOL(pm_power_off);
static int hlt_counter = 1;
void disable_hlt(void)
{
hlt_counter++;
}
EXPORT_SYMBOL(disable_hlt);
void enable_hlt(void)
{
hlt_counter--;
}
EXPORT_SYMBOL(enable_hlt);
static int __init nohlt_setup(char *__unused)
{
hlt_counter = 1;
return 1;
}
__setup("nohlt", nohlt_setup);
static int __init hlt_setup(char *__unused)
{
hlt_counter = 0;
return 1;
}
__setup("hlt", hlt_setup);
void default_idle(void)
{
if (!hlt_counter) {
clear_thread_flag(TIF_POLLING_NRFLAG);
smp_mb__after_clear_bit();
local_irq_disable();
while (!need_resched())
cpu_sleep();
local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
} else
while (!need_resched())
cpu_relax();
}
void cpu_idle(void)
{
set_thread_flag(TIF_POLLING_NRFLAG);
/* endless idle loop with no priority at all */
while (1) {
void (*idle)(void) = pm_idle;
if (!idle)
idle = default_idle;
tick_nohz_stop_sched_tick(1);
while (!need_resched())
idle();
tick_nohz_restart_sched_tick();
preempt_enable_no_resched();
schedule();
preempt_disable();
check_pgt_cache();
}
}
void flush_thread(void)
{
}
int copy_thread(unsigned long clone_flags, unsigned long usp,
unsigned long unused,
struct task_struct *p, struct pt_regs *regs)
{
struct pt_regs *childregs = task_pt_regs(p);
struct thread_info *ti = task_thread_info(p);
*childregs = *regs;
if (user_mode(regs))
childregs->r1 = usp;
else
childregs->r1 = ((unsigned long) ti) + THREAD_SIZE;
#ifndef CONFIG_MMU
memset(&ti->cpu_context, 0, sizeof(struct cpu_context));
ti->cpu_context.r1 = (unsigned long)childregs;
ti->cpu_context.msr = (unsigned long)childregs->msr;
#else
/* if creating a kernel thread then update the current reg (we don't
* want to use the parent's value when restoring by POP_STATE) */
if (kernel_mode(regs))
/* save new current on stack to use POP_STATE */
childregs->CURRENT_TASK = (unsigned long)p;
/* if returning to user then use the parent's value of this register */
/* if we're creating a new kernel thread then just zeroing all
* the registers. That's OK for a brand new thread.*/
/* Pls. note that some of them will be restored in POP_STATE */
if (kernel_mode(regs))
memset(&ti->cpu_context, 0, sizeof(struct cpu_context));
/* if this thread is created for fork/vfork/clone, then we want to
* restore all the parent's context */
/* in addition to the registers which will be restored by POP_STATE */
else {
ti->cpu_context = *(struct cpu_context *)regs;
childregs->msr |= MSR_UMS;
}
/* FIXME STATE_SAVE_PT_OFFSET; */
ti->cpu_context.r1 = (unsigned long)childregs - STATE_SAVE_ARG_SPACE;
/* we should consider the fact that childregs is a copy of the parent
* regs which were saved immediately after entering the kernel state
* before enabling VM. This MSR will be restored in switch_to and
* RETURN() and we want to have the right machine state there
* specifically this state must have INTs disabled before and enabled
* after performing rtbd
* compose the right MSR for RETURN(). It will work for switch_to also
* excepting for VM and UMS
* don't touch UMS , CARRY and cache bits
* right now MSR is a copy of parent one */
childregs->msr |= MSR_BIP;
childregs->msr &= ~MSR_EIP;
childregs->msr |= MSR_IE;
childregs->msr &= ~MSR_VM;
childregs->msr |= MSR_VMS;
childregs->msr |= MSR_EE; /* exceptions will be enabled*/
ti->cpu_context.msr = (childregs->msr|MSR_VM);
ti->cpu_context.msr &= ~MSR_UMS; /* switch_to to kernel mode */
#endif
ti->cpu_context.r15 = (unsigned long)ret_from_fork - 8;
if (clone_flags & CLONE_SETTLS)
;
return 0;
}
#ifndef CONFIG_MMU
/*
* Return saved PC of a blocked thread.
*/
unsigned long thread_saved_pc(struct task_struct *tsk)
{
struct cpu_context *ctx =
&(((struct thread_info *)(tsk->stack))->cpu_context);
/* Check whether the thread is blocked in resume() */
if (in_sched_functions(ctx->r15))
return (unsigned long)ctx->r15;
else
return ctx->r14;
}
#endif
static void kernel_thread_helper(int (*fn)(void *), void *arg)
{
fn(arg);
do_exit(-1);
}
int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
{
struct pt_regs regs;
memset(®s, 0, sizeof(regs));
/* store them in non-volatile registers */
regs.r5 = (unsigned long)fn;
regs.r6 = (unsigned long)arg;
local_save_flags(regs.msr);
regs.pc = (unsigned long)kernel_thread_helper;
regs.pt_mode = 1;
return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
®s, 0, NULL, NULL);
}
EXPORT_SYMBOL_GPL(kernel_thread);
unsigned long get_wchan(struct task_struct *p)
{
/* TBD (used by procfs) */
return 0;
}
/* Set up a thread for executing a new program */
void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp)
{
set_fs(USER_DS);
regs->pc = pc;
regs->r1 = usp;
regs->pt_mode = 0;
}
#ifdef CONFIG_MMU
#include <linux/elfcore.h>
/*
* Set up a thread for executing a new program
*/
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs)
{
return 0; /* MicroBlaze has no separate FPU registers */
}
#endif /* CONFIG_MMU */
|
