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.
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.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>
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/stacktrace.h>
41 static const char * const processor_modes[] = {
42 "UK00", "UK01", "UK02", "UK03", "UK04", "UK05", "UK06", "UK07",
43 "UK08", "UK09", "UK0A", "UK0B", "UK0C", "UK0D", "UK0E", "UK0F",
44 "USER", "REAL", "INTR", "PRIV", "UK14", "UK15", "UK16", "ABRT",
45 "UK18", "UK19", "UK1A", "EXTN", "UK1C", "UK1D", "UK1E", "SUSR"
50 /* endless idle loop with no priority at all */
52 tick_nohz_idle_enter();
54 while (!need_resched()) {
56 stop_critical_timings();
59 start_critical_timings();
62 tick_nohz_idle_exit();
63 preempt_enable_no_resched();
69 static char reboot_mode = 'h';
71 int __init reboot_setup(char *str)
77 __setup("reboot=", reboot_setup);
79 void machine_halt(void)
81 gpio_set_value(GPO_SOFT_OFF, 0);
85 * Function pointers to optional machine specific functions
87 void (*pm_power_off)(void) = NULL;
89 void machine_power_off(void)
96 void machine_restart(char *cmd)
98 /* Disable interrupts first */
102 * Tell the mm system that we are going to reboot -
103 * we may need it to insert some 1:1 mappings so that
106 setup_mm_for_reboot(reboot_mode);
108 /* Clean and invalidate caches */
111 /* Turn off caching */
114 /* Push out any further dirty data, and ensure cache is empty */
118 * Now handle reboot code.
120 if (reboot_mode == 's') {
121 /* Jump into ROM at address 0xffff0000 */
122 cpu_reset(VECTORS_BASE);
124 writel(0x00002001, PM_PLLSYSCFG); /* cpu clk = 250M */
125 writel(0x00100800, PM_PLLDDRCFG); /* ddr clk = 44M */
126 writel(0x00002001, PM_PLLVGACFG); /* vga clk = 250M */
128 /* Use on-chip reset capability */
129 /* following instructions must be in one icache line */
130 __asm__ __volatile__(
133 "201: ldw r0, [%0]\n\t"
134 " cmpsub.a r0, #0\n\t"
138 /* prefetch 3 instructions at most */
141 "r" (PM_PMCR_CFBSYS | PM_PMCR_CFBDDR
144 "r" (RESETC_SWRR_SRB)
149 * Whoops - the architecture was unable to reboot.
153 printk(KERN_EMERG "Reboot failed -- System halted\n");
157 void __show_regs(struct pt_regs *regs)
162 printk(KERN_DEFAULT "CPU: %d %s (%s %.*s)\n",
163 raw_smp_processor_id(), print_tainted(),
164 init_utsname()->release,
165 (int)strcspn(init_utsname()->version, " "),
166 init_utsname()->version);
167 print_symbol("PC is at %s\n", instruction_pointer(regs));
168 print_symbol("LR is at %s\n", regs->UCreg_lr);
169 printk(KERN_DEFAULT "pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
170 "sp : %08lx ip : %08lx fp : %08lx\n",
171 regs->UCreg_pc, regs->UCreg_lr, regs->UCreg_asr,
172 regs->UCreg_sp, regs->UCreg_ip, regs->UCreg_fp);
173 printk(KERN_DEFAULT "r26: %08lx r25: %08lx r24: %08lx\n",
174 regs->UCreg_26, regs->UCreg_25,
176 printk(KERN_DEFAULT "r23: %08lx r22: %08lx r21: %08lx r20: %08lx\n",
177 regs->UCreg_23, regs->UCreg_22,
178 regs->UCreg_21, regs->UCreg_20);
179 printk(KERN_DEFAULT "r19: %08lx r18: %08lx r17: %08lx r16: %08lx\n",
180 regs->UCreg_19, regs->UCreg_18,
181 regs->UCreg_17, regs->UCreg_16);
182 printk(KERN_DEFAULT "r15: %08lx r14: %08lx r13: %08lx r12: %08lx\n",
183 regs->UCreg_15, regs->UCreg_14,
184 regs->UCreg_13, regs->UCreg_12);
185 printk(KERN_DEFAULT "r11: %08lx r10: %08lx r9 : %08lx r8 : %08lx\n",
186 regs->UCreg_11, regs->UCreg_10,
187 regs->UCreg_09, regs->UCreg_08);
188 printk(KERN_DEFAULT "r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
189 regs->UCreg_07, regs->UCreg_06,
190 regs->UCreg_05, regs->UCreg_04);
191 printk(KERN_DEFAULT "r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
192 regs->UCreg_03, regs->UCreg_02,
193 regs->UCreg_01, regs->UCreg_00);
195 flags = regs->UCreg_asr;
196 buf[0] = flags & PSR_S_BIT ? 'S' : 's';
197 buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
198 buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
199 buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
202 printk(KERN_DEFAULT "Flags: %s INTR o%s REAL o%s Mode %s Segment %s\n",
203 buf, interrupts_enabled(regs) ? "n" : "ff",
204 fast_interrupts_enabled(regs) ? "n" : "ff",
205 processor_modes[processor_mode(regs)],
206 segment_eq(get_fs(), get_ds()) ? "kernel" : "user");
212 unsigned int transbase;
213 asm("movc %0, p0.c2, #0\n"
215 snprintf(buf, sizeof(buf), " Table: %08x", transbase);
217 asm("movc %0, p0.c1, #0\n" : "=r" (ctrl));
219 printk(KERN_DEFAULT "Control: %08x%s\n", ctrl, buf);
223 void show_regs(struct pt_regs *regs)
225 printk(KERN_DEFAULT "\n");
226 printk(KERN_DEFAULT "Pid: %d, comm: %20s\n",
227 task_pid_nr(current), current->comm);
233 * Free current thread data structures etc..
235 void exit_thread(void)
239 void flush_thread(void)
241 struct thread_info *thread = current_thread_info();
242 struct task_struct *tsk = current;
244 memset(thread->used_cp, 0, sizeof(thread->used_cp));
245 memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
246 #ifdef CONFIG_UNICORE_FPU_F64
247 memset(&thread->fpstate, 0, sizeof(struct fp_state));
251 void release_thread(struct task_struct *dead_task)
255 asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
256 asmlinkage void ret_from_kernel_thread(void) __asm__("ret_from_kernel_thread");
259 copy_thread(unsigned long clone_flags, unsigned long stack_start,
260 unsigned long stk_sz, struct task_struct *p)
262 struct thread_info *thread = task_thread_info(p);
263 struct pt_regs *childregs = task_pt_regs(p);
265 memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
266 thread->cpu_context.sp = (unsigned long)childregs;
267 if (unlikely(p->flags & PF_KTHREAD)) {
268 thread->cpu_context.pc = (unsigned long)ret_from_kernel_thread;
269 thread->cpu_context.r4 = stack_start;
270 thread->cpu_context.r5 = stk_sz;
271 memset(childregs, 0, sizeof(struct pt_regs));
273 thread->cpu_context.pc = (unsigned long)ret_from_fork;
274 *childregs = *current_pt_regs();
275 childregs->UCreg_00 = 0;
277 childregs->UCreg_sp = stack_start;
279 if (clone_flags & CLONE_SETTLS)
280 childregs->UCreg_16 = childregs->UCreg_03;
286 * Fill in the task's elfregs structure for a core dump.
288 int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs)
290 elf_core_copy_regs(elfregs, task_pt_regs(t));
295 * fill in the fpe structure for a core dump...
297 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fp)
299 struct thread_info *thread = current_thread_info();
300 int used_math = thread->used_cp[1] | thread->used_cp[2];
302 #ifdef CONFIG_UNICORE_FPU_F64
304 memcpy(fp, &thread->fpstate, sizeof(*fp));
306 return used_math != 0;
308 EXPORT_SYMBOL(dump_fpu);
310 unsigned long get_wchan(struct task_struct *p)
312 struct stackframe frame;
314 if (!p || p == current || p->state == TASK_RUNNING)
317 frame.fp = thread_saved_fp(p);
318 frame.sp = thread_saved_sp(p);
319 frame.lr = 0; /* recovered from the stack */
320 frame.pc = thread_saved_pc(p);
322 int ret = unwind_frame(&frame);
325 if (!in_sched_functions(frame.pc))
327 } while ((count++) < 16);
331 unsigned long arch_randomize_brk(struct mm_struct *mm)
333 unsigned long range_end = mm->brk + 0x02000000;
334 return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
338 * The vectors page is always readable from user space for the
339 * atomic helpers and the signal restart code. Let's declare a mapping
340 * for it so it is visible through ptrace and /proc/<pid>/mem.
343 int vectors_user_mapping(void)
345 struct mm_struct *mm = current->mm;
346 return install_special_mapping(mm, 0xffff0000, PAGE_SIZE,
348 VM_MAYREAD | VM_MAYEXEC |
349 VM_DONTEXPAND | VM_DONTDUMP,
353 const char *arch_vma_name(struct vm_area_struct *vma)
355 return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL;