kvm tools, setup: Create private directory
[linux-2.6/next.git] / arch / microblaze / kernel / process.c
blob968648a81c1ebbda34c1565b61a25571f9cd55e7
1 /*
2 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
3 * Copyright (C) 2008-2009 PetaLogix
4 * Copyright (C) 2006 Atmark Techno, Inc.
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
11 #include <linux/module.h>
12 #include <linux/sched.h>
13 #include <linux/pm.h>
14 #include <linux/tick.h>
15 #include <linux/bitops.h>
16 #include <asm/system.h>
17 #include <asm/pgalloc.h>
18 #include <asm/uaccess.h> /* for USER_DS macros */
19 #include <asm/cacheflush.h>
21 void show_regs(struct pt_regs *regs)
23 printk(KERN_INFO " Registers dump: mode=%X\r\n", regs->pt_mode);
24 printk(KERN_INFO " r1=%08lX, r2=%08lX, r3=%08lX, r4=%08lX\n",
25 regs->r1, regs->r2, regs->r3, regs->r4);
26 printk(KERN_INFO " r5=%08lX, r6=%08lX, r7=%08lX, r8=%08lX\n",
27 regs->r5, regs->r6, regs->r7, regs->r8);
28 printk(KERN_INFO " r9=%08lX, r10=%08lX, r11=%08lX, r12=%08lX\n",
29 regs->r9, regs->r10, regs->r11, regs->r12);
30 printk(KERN_INFO " r13=%08lX, r14=%08lX, r15=%08lX, r16=%08lX\n",
31 regs->r13, regs->r14, regs->r15, regs->r16);
32 printk(KERN_INFO " r17=%08lX, r18=%08lX, r19=%08lX, r20=%08lX\n",
33 regs->r17, regs->r18, regs->r19, regs->r20);
34 printk(KERN_INFO " r21=%08lX, r22=%08lX, r23=%08lX, r24=%08lX\n",
35 regs->r21, regs->r22, regs->r23, regs->r24);
36 printk(KERN_INFO " r25=%08lX, r26=%08lX, r27=%08lX, r28=%08lX\n",
37 regs->r25, regs->r26, regs->r27, regs->r28);
38 printk(KERN_INFO " r29=%08lX, r30=%08lX, r31=%08lX, rPC=%08lX\n",
39 regs->r29, regs->r30, regs->r31, regs->pc);
40 printk(KERN_INFO " msr=%08lX, ear=%08lX, esr=%08lX, fsr=%08lX\n",
41 regs->msr, regs->ear, regs->esr, regs->fsr);
44 void (*pm_idle)(void);
45 void (*pm_power_off)(void) = NULL;
46 EXPORT_SYMBOL(pm_power_off);
48 static int hlt_counter = 1;
50 void disable_hlt(void)
52 hlt_counter++;
54 EXPORT_SYMBOL(disable_hlt);
56 void enable_hlt(void)
58 hlt_counter--;
60 EXPORT_SYMBOL(enable_hlt);
62 static int __init nohlt_setup(char *__unused)
64 hlt_counter = 1;
65 return 1;
67 __setup("nohlt", nohlt_setup);
69 static int __init hlt_setup(char *__unused)
71 hlt_counter = 0;
72 return 1;
74 __setup("hlt", hlt_setup);
76 void default_idle(void)
78 if (likely(hlt_counter)) {
79 local_irq_disable();
80 stop_critical_timings();
81 cpu_relax();
82 start_critical_timings();
83 local_irq_enable();
84 } else {
85 clear_thread_flag(TIF_POLLING_NRFLAG);
86 smp_mb__after_clear_bit();
87 local_irq_disable();
88 while (!need_resched())
89 cpu_sleep();
90 local_irq_enable();
91 set_thread_flag(TIF_POLLING_NRFLAG);
95 void cpu_idle(void)
97 set_thread_flag(TIF_POLLING_NRFLAG);
99 /* endless idle loop with no priority at all */
100 while (1) {
101 void (*idle)(void) = pm_idle;
103 if (!idle)
104 idle = default_idle;
106 tick_nohz_stop_sched_tick(1);
107 while (!need_resched())
108 idle();
109 tick_nohz_restart_sched_tick();
111 preempt_enable_no_resched();
112 schedule();
113 preempt_disable();
114 check_pgt_cache();
118 void flush_thread(void)
122 int copy_thread(unsigned long clone_flags, unsigned long usp,
123 unsigned long unused,
124 struct task_struct *p, struct pt_regs *regs)
126 struct pt_regs *childregs = task_pt_regs(p);
127 struct thread_info *ti = task_thread_info(p);
129 *childregs = *regs;
130 if (user_mode(regs))
131 childregs->r1 = usp;
132 else
133 childregs->r1 = ((unsigned long) ti) + THREAD_SIZE;
135 #ifndef CONFIG_MMU
136 memset(&ti->cpu_context, 0, sizeof(struct cpu_context));
137 ti->cpu_context.r1 = (unsigned long)childregs;
138 ti->cpu_context.msr = (unsigned long)childregs->msr;
139 #else
141 /* if creating a kernel thread then update the current reg (we don't
142 * want to use the parent's value when restoring by POP_STATE) */
143 if (kernel_mode(regs))
144 /* save new current on stack to use POP_STATE */
145 childregs->CURRENT_TASK = (unsigned long)p;
146 /* if returning to user then use the parent's value of this register */
148 /* if we're creating a new kernel thread then just zeroing all
149 * the registers. That's OK for a brand new thread.*/
150 /* Pls. note that some of them will be restored in POP_STATE */
151 if (kernel_mode(regs))
152 memset(&ti->cpu_context, 0, sizeof(struct cpu_context));
153 /* if this thread is created for fork/vfork/clone, then we want to
154 * restore all the parent's context */
155 /* in addition to the registers which will be restored by POP_STATE */
156 else {
157 ti->cpu_context = *(struct cpu_context *)regs;
158 childregs->msr |= MSR_UMS;
161 /* FIXME STATE_SAVE_PT_OFFSET; */
162 ti->cpu_context.r1 = (unsigned long)childregs;
163 /* we should consider the fact that childregs is a copy of the parent
164 * regs which were saved immediately after entering the kernel state
165 * before enabling VM. This MSR will be restored in switch_to and
166 * RETURN() and we want to have the right machine state there
167 * specifically this state must have INTs disabled before and enabled
168 * after performing rtbd
169 * compose the right MSR for RETURN(). It will work for switch_to also
170 * excepting for VM and UMS
171 * don't touch UMS , CARRY and cache bits
172 * right now MSR is a copy of parent one */
173 childregs->msr |= MSR_BIP;
174 childregs->msr &= ~MSR_EIP;
175 childregs->msr |= MSR_IE;
176 childregs->msr &= ~MSR_VM;
177 childregs->msr |= MSR_VMS;
178 childregs->msr |= MSR_EE; /* exceptions will be enabled*/
180 ti->cpu_context.msr = (childregs->msr|MSR_VM);
181 ti->cpu_context.msr &= ~MSR_UMS; /* switch_to to kernel mode */
182 #endif
183 ti->cpu_context.r15 = (unsigned long)ret_from_fork - 8;
185 if (clone_flags & CLONE_SETTLS)
188 return 0;
191 #ifndef CONFIG_MMU
193 * Return saved PC of a blocked thread.
195 unsigned long thread_saved_pc(struct task_struct *tsk)
197 struct cpu_context *ctx =
198 &(((struct thread_info *)(tsk->stack))->cpu_context);
200 /* Check whether the thread is blocked in resume() */
201 if (in_sched_functions(ctx->r15))
202 return (unsigned long)ctx->r15;
203 else
204 return ctx->r14;
206 #endif
208 static void kernel_thread_helper(int (*fn)(void *), void *arg)
210 fn(arg);
211 do_exit(-1);
214 int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
216 struct pt_regs regs;
218 memset(&regs, 0, sizeof(regs));
219 /* store them in non-volatile registers */
220 regs.r5 = (unsigned long)fn;
221 regs.r6 = (unsigned long)arg;
222 local_save_flags(regs.msr);
223 regs.pc = (unsigned long)kernel_thread_helper;
224 regs.pt_mode = 1;
226 return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
227 &regs, 0, NULL, NULL);
229 EXPORT_SYMBOL_GPL(kernel_thread);
231 unsigned long get_wchan(struct task_struct *p)
233 /* TBD (used by procfs) */
234 return 0;
237 /* Set up a thread for executing a new program */
238 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp)
240 set_fs(USER_DS);
241 regs->pc = pc;
242 regs->r1 = usp;
243 regs->pt_mode = 0;
244 #ifdef CONFIG_MMU
245 regs->msr |= MSR_UMS;
246 #endif
249 #ifdef CONFIG_MMU
250 #include <linux/elfcore.h>
252 * Set up a thread for executing a new program
254 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs)
256 return 0; /* MicroBlaze has no separate FPU registers */
258 #endif /* CONFIG_MMU */