Avoid beyond bounds copy while caching ACL
[zen-stable.git] / arch / unicore32 / kernel / process.c
blob52edc2b628732552c1e8cc6578acb5fe2a8a0427
1 /*
2 * linux/arch/unicore32/kernel/process.c
4 * Code specific to PKUnity SoC and UniCore ISA
6 * Copyright (C) 2001-2010 GUAN Xue-tao
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
12 #include <stdarg.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
17 #include <linux/mm.h>
18 #include <linux/stddef.h>
19 #include <linux/unistd.h>
20 #include <linux/delay.h>
21 #include <linux/reboot.h>
22 #include <linux/interrupt.h>
23 #include <linux/kallsyms.h>
24 #include <linux/init.h>
25 #include <linux/cpu.h>
26 #include <linux/elfcore.h>
27 #include <linux/pm.h>
28 #include <linux/tick.h>
29 #include <linux/utsname.h>
30 #include <linux/uaccess.h>
31 #include <linux/random.h>
32 #include <linux/gpio.h>
33 #include <linux/stacktrace.h>
35 #include <asm/cacheflush.h>
36 #include <asm/processor.h>
37 #include <asm/system.h>
38 #include <asm/stacktrace.h>
40 #include "setup.h"
42 static const char * const processor_modes[] = {
43 "UK00", "UK01", "UK02", "UK03", "UK04", "UK05", "UK06", "UK07",
44 "UK08", "UK09", "UK0A", "UK0B", "UK0C", "UK0D", "UK0E", "UK0F",
45 "USER", "REAL", "INTR", "PRIV", "UK14", "UK15", "UK16", "ABRT",
46 "UK18", "UK19", "UK1A", "EXTN", "UK1C", "UK1D", "UK1E", "SUSR"
50 * The idle thread, has rather strange semantics for calling pm_idle,
51 * but this is what x86 does and we need to do the same, so that
52 * things like cpuidle get called in the same way.
54 void cpu_idle(void)
56 /* endless idle loop with no priority at all */
57 while (1) {
58 tick_nohz_idle_enter();
59 rcu_idle_enter();
60 while (!need_resched()) {
61 local_irq_disable();
62 stop_critical_timings();
63 cpu_do_idle();
64 local_irq_enable();
65 start_critical_timings();
67 rcu_idle_exit();
68 tick_nohz_idle_exit();
69 preempt_enable_no_resched();
70 schedule();
71 preempt_disable();
75 static char reboot_mode = 'h';
77 int __init reboot_setup(char *str)
79 reboot_mode = str[0];
80 return 1;
83 __setup("reboot=", reboot_setup);
85 void machine_halt(void)
87 gpio_set_value(GPO_SOFT_OFF, 0);
91 * Function pointers to optional machine specific functions
93 void (*pm_power_off)(void) = NULL;
95 void machine_power_off(void)
97 if (pm_power_off)
98 pm_power_off();
99 machine_halt();
102 void machine_restart(char *cmd)
104 /* Disable interrupts first */
105 local_irq_disable();
108 * Tell the mm system that we are going to reboot -
109 * we may need it to insert some 1:1 mappings so that
110 * soft boot works.
112 setup_mm_for_reboot(reboot_mode);
114 /* Clean and invalidate caches */
115 flush_cache_all();
117 /* Turn off caching */
118 cpu_proc_fin();
120 /* Push out any further dirty data, and ensure cache is empty */
121 flush_cache_all();
124 * Now handle reboot code.
126 if (reboot_mode == 's') {
127 /* Jump into ROM at address 0xffff0000 */
128 cpu_reset(VECTORS_BASE);
129 } else {
130 writel(0x00002001, PM_PLLSYSCFG); /* cpu clk = 250M */
131 writel(0x00100800, PM_PLLDDRCFG); /* ddr clk = 44M */
132 writel(0x00002001, PM_PLLVGACFG); /* vga clk = 250M */
134 /* Use on-chip reset capability */
135 /* following instructions must be in one icache line */
136 __asm__ __volatile__(
137 " .align 5\n\t"
138 " stw %1, [%0]\n\t"
139 "201: ldw r0, [%0]\n\t"
140 " cmpsub.a r0, #0\n\t"
141 " bne 201b\n\t"
142 " stw %3, [%2]\n\t"
143 " nop; nop; nop\n\t"
144 /* prefetch 3 instructions at most */
146 : "r" (PM_PMCR),
147 "r" (PM_PMCR_CFBSYS | PM_PMCR_CFBDDR
148 | PM_PMCR_CFBVGA),
149 "r" (RESETC_SWRR),
150 "r" (RESETC_SWRR_SRB)
151 : "r0", "memory");
155 * Whoops - the architecture was unable to reboot.
156 * Tell the user!
158 mdelay(1000);
159 printk(KERN_EMERG "Reboot failed -- System halted\n");
160 do { } while (1);
163 void __show_regs(struct pt_regs *regs)
165 unsigned long flags;
166 char buf[64];
168 printk(KERN_DEFAULT "CPU: %d %s (%s %.*s)\n",
169 raw_smp_processor_id(), print_tainted(),
170 init_utsname()->release,
171 (int)strcspn(init_utsname()->version, " "),
172 init_utsname()->version);
173 print_symbol("PC is at %s\n", instruction_pointer(regs));
174 print_symbol("LR is at %s\n", regs->UCreg_lr);
175 printk(KERN_DEFAULT "pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
176 "sp : %08lx ip : %08lx fp : %08lx\n",
177 regs->UCreg_pc, regs->UCreg_lr, regs->UCreg_asr,
178 regs->UCreg_sp, regs->UCreg_ip, regs->UCreg_fp);
179 printk(KERN_DEFAULT "r26: %08lx r25: %08lx r24: %08lx\n",
180 regs->UCreg_26, regs->UCreg_25,
181 regs->UCreg_24);
182 printk(KERN_DEFAULT "r23: %08lx r22: %08lx r21: %08lx r20: %08lx\n",
183 regs->UCreg_23, regs->UCreg_22,
184 regs->UCreg_21, regs->UCreg_20);
185 printk(KERN_DEFAULT "r19: %08lx r18: %08lx r17: %08lx r16: %08lx\n",
186 regs->UCreg_19, regs->UCreg_18,
187 regs->UCreg_17, regs->UCreg_16);
188 printk(KERN_DEFAULT "r15: %08lx r14: %08lx r13: %08lx r12: %08lx\n",
189 regs->UCreg_15, regs->UCreg_14,
190 regs->UCreg_13, regs->UCreg_12);
191 printk(KERN_DEFAULT "r11: %08lx r10: %08lx r9 : %08lx r8 : %08lx\n",
192 regs->UCreg_11, regs->UCreg_10,
193 regs->UCreg_09, regs->UCreg_08);
194 printk(KERN_DEFAULT "r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
195 regs->UCreg_07, regs->UCreg_06,
196 regs->UCreg_05, regs->UCreg_04);
197 printk(KERN_DEFAULT "r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
198 regs->UCreg_03, regs->UCreg_02,
199 regs->UCreg_01, regs->UCreg_00);
201 flags = regs->UCreg_asr;
202 buf[0] = flags & PSR_S_BIT ? 'S' : 's';
203 buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
204 buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
205 buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
206 buf[4] = '\0';
208 printk(KERN_DEFAULT "Flags: %s INTR o%s REAL o%s Mode %s Segment %s\n",
209 buf, interrupts_enabled(regs) ? "n" : "ff",
210 fast_interrupts_enabled(regs) ? "n" : "ff",
211 processor_modes[processor_mode(regs)],
212 segment_eq(get_fs(), get_ds()) ? "kernel" : "user");
214 unsigned int ctrl;
216 buf[0] = '\0';
218 unsigned int transbase;
219 asm("movc %0, p0.c2, #0\n"
220 : "=r" (transbase));
221 snprintf(buf, sizeof(buf), " Table: %08x", transbase);
223 asm("movc %0, p0.c1, #0\n" : "=r" (ctrl));
225 printk(KERN_DEFAULT "Control: %08x%s\n", ctrl, buf);
229 void show_regs(struct pt_regs *regs)
231 printk(KERN_DEFAULT "\n");
232 printk(KERN_DEFAULT "Pid: %d, comm: %20s\n",
233 task_pid_nr(current), current->comm);
234 __show_regs(regs);
235 __backtrace();
239 * Free current thread data structures etc..
241 void exit_thread(void)
245 void flush_thread(void)
247 struct thread_info *thread = current_thread_info();
248 struct task_struct *tsk = current;
250 memset(thread->used_cp, 0, sizeof(thread->used_cp));
251 memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
252 #ifdef CONFIG_UNICORE_FPU_F64
253 memset(&thread->fpstate, 0, sizeof(struct fp_state));
254 #endif
257 void release_thread(struct task_struct *dead_task)
261 asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
264 copy_thread(unsigned long clone_flags, unsigned long stack_start,
265 unsigned long stk_sz, struct task_struct *p, struct pt_regs *regs)
267 struct thread_info *thread = task_thread_info(p);
268 struct pt_regs *childregs = task_pt_regs(p);
270 *childregs = *regs;
271 childregs->UCreg_00 = 0;
272 childregs->UCreg_sp = stack_start;
274 memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
275 thread->cpu_context.sp = (unsigned long)childregs;
276 thread->cpu_context.pc = (unsigned long)ret_from_fork;
278 if (clone_flags & CLONE_SETTLS)
279 childregs->UCreg_16 = regs->UCreg_03;
281 return 0;
285 * Fill in the task's elfregs structure for a core dump.
287 int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs)
289 elf_core_copy_regs(elfregs, task_pt_regs(t));
290 return 1;
294 * fill in the fpe structure for a core dump...
296 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fp)
298 struct thread_info *thread = current_thread_info();
299 int used_math = thread->used_cp[1] | thread->used_cp[2];
301 #ifdef CONFIG_UNICORE_FPU_F64
302 if (used_math)
303 memcpy(fp, &thread->fpstate, sizeof(*fp));
304 #endif
305 return used_math != 0;
307 EXPORT_SYMBOL(dump_fpu);
310 * Shuffle the argument into the correct register before calling the
311 * thread function. r1 is the thread argument, r2 is the pointer to
312 * the thread function, and r3 points to the exit function.
314 asm(".pushsection .text\n"
315 " .align\n"
316 " .type kernel_thread_helper, #function\n"
317 "kernel_thread_helper:\n"
318 " mov.a asr, r7\n"
319 " mov r0, r4\n"
320 " mov lr, r6\n"
321 " mov pc, r5\n"
322 " .size kernel_thread_helper, . - kernel_thread_helper\n"
323 " .popsection");
326 * Create a kernel thread.
328 pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
330 struct pt_regs regs;
332 memset(&regs, 0, sizeof(regs));
334 regs.UCreg_04 = (unsigned long)arg;
335 regs.UCreg_05 = (unsigned long)fn;
336 regs.UCreg_06 = (unsigned long)do_exit;
337 regs.UCreg_07 = PRIV_MODE;
338 regs.UCreg_pc = (unsigned long)kernel_thread_helper;
339 regs.UCreg_asr = regs.UCreg_07 | PSR_I_BIT;
341 return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
343 EXPORT_SYMBOL(kernel_thread);
345 unsigned long get_wchan(struct task_struct *p)
347 struct stackframe frame;
348 int count = 0;
349 if (!p || p == current || p->state == TASK_RUNNING)
350 return 0;
352 frame.fp = thread_saved_fp(p);
353 frame.sp = thread_saved_sp(p);
354 frame.lr = 0; /* recovered from the stack */
355 frame.pc = thread_saved_pc(p);
356 do {
357 int ret = unwind_frame(&frame);
358 if (ret < 0)
359 return 0;
360 if (!in_sched_functions(frame.pc))
361 return frame.pc;
362 } while ((count++) < 16);
363 return 0;
366 unsigned long arch_randomize_brk(struct mm_struct *mm)
368 unsigned long range_end = mm->brk + 0x02000000;
369 return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
373 * The vectors page is always readable from user space for the
374 * atomic helpers and the signal restart code. Let's declare a mapping
375 * for it so it is visible through ptrace and /proc/<pid>/mem.
378 int vectors_user_mapping(void)
380 struct mm_struct *mm = current->mm;
381 return install_special_mapping(mm, 0xffff0000, PAGE_SIZE,
382 VM_READ | VM_EXEC |
383 VM_MAYREAD | VM_MAYEXEC |
384 VM_ALWAYSDUMP | VM_RESERVED,
385 NULL);
388 const char *arch_vma_name(struct vm_area_struct *vma)
390 return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL;