/*
* linux/arch/unicore32/kernel/process.c
*
* Code specific to PKUnity SoC and UniCore ISA
*
* Copyright (C) 2001-2010 GUAN Xue-tao
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <stdarg.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/delay.h>
#include <linux/reboot.h>
#include <linux/interrupt.h>
#include <linux/kallsyms.h>
#include <linux/init.h>
#include <linux/cpu.h>
#include <linux/elfcore.h>
#include <linux/pm.h>
#include <linux/tick.h>
#include <linux/utsname.h>
#include <linux/uaccess.h>
#include <linux/random.h>
#include <linux/gpio.h>
#include <linux/stacktrace.h>
#include <asm/cacheflush.h>
#include <asm/processor.h>
#include <asm/stacktrace.h>
#include "setup.h"
static const char * const processor_modes[] = {
"UK00", "UK01", "UK02", "UK03", "UK04", "UK05", "UK06", "UK07",
"UK08", "UK09", "UK0A", "UK0B", "UK0C", "UK0D", "UK0E", "UK0F",
"USER", "REAL", "INTR", "PRIV", "UK14", "UK15", "UK16", "ABRT",
"UK18", "UK19", "UK1A", "EXTN", "UK1C", "UK1D", "UK1E", "SUSR"
};
void arch_cpu_idle(void)
{
cpu_do_idle();
local_irq_enable();
}
void machine_halt(void)
{
gpio_set_value(GPO_SOFT_OFF, 0);
}
/*
* Function pointers to optional machine specific functions
*/
void (*pm_power_off)(void) = NULL;
void machine_power_off(void)
{
if (pm_power_off)
pm_power_off();
machine_halt();
}
void machine_restart(char *cmd)
{
/* Disable interrupts first */
local_irq_disable();
/*
* Tell the mm system that we are going to reboot -
* we may need it to insert some 1:1 mappings so that
* soft boot works.
*/
setup_mm_for_reboot();
/* Clean and invalidate caches */
flush_cache_all();
/* Turn off caching */
cpu_proc_fin();
/* Push out any further dirty data, and ensure cache is empty */
flush_cache_all();
/*
* Now handle reboot code.
*/
if (reboot_mode == REBOOT_SOFT) {
/* Jump into ROM at address 0xffff0000 */
cpu_reset(VECTORS_BASE);
} else {
writel(0x00002001, PM_PLLSYSCFG); /* cpu clk = 250M */
writel(0x00100800, PM_PLLDDRCFG); /* ddr clk = 44M */
writel(0x00002001, PM_PLLVGACFG); /* vga clk = 250M */
/* Use on-chip reset capability */
/* following instructions must be in one icache line */
__asm__ __volatile__(
" .align 5\n\t"
" stw %1, [%0]\n\t"
"201: ldw r0, [%0]\n\t"
" cmpsub.a r0, #0\n\t"
" bne 201b\n\t"
" stw %3, [%2]\n\t"
" nop; nop; nop\n\t"
/* prefetch 3 instructions at most */
:
: "r" (PM_PMCR),
"r" (PM_PMCR_CFBSYS | PM_PMCR_CFBDDR
| PM_PMCR_CFBVGA),
"r" (RESETC_SWRR),
"r" (RESETC_SWRR_SRB)
: "r0", "memory");
}
/*
* Whoops - the architecture was unable to reboot.
* Tell the user!
*/
mdelay(1000);
printk(KERN_EMERG "Reboot failed -- System halted\n");
do { } while (1);
}
void __show_regs(struct pt_regs *regs)
{
unsigned long flags;
char buf[64];
show_regs_print_info(KERN_DEFAULT);
print_symbol("PC is at %s\n", instruction_pointer(regs));
print_symbol("LR is at %s\n", regs->UCreg_lr);
printk(KERN_DEFAULT "pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
"sp : %08lx ip : %08lx fp : %08lx\n",
regs->UCreg_pc, regs->UCreg_lr, regs->UCreg_asr,
regs->UCreg_sp, regs->UCreg_ip, regs->UCreg_fp);
printk(KERN_DEFAULT "r26: %08lx r25: %08lx r24: %08lx\n",
regs->UCreg_26, regs->UCreg_25,
regs->UCreg_24);
printk(KERN_DEFAULT "r23: %08lx r22: %08lx r21: %08lx r20: %08lx\n",
regs->UCreg_23, regs->UCreg_22,
regs->UCreg_21, regs->UCreg_20);
printk(KERN_DEFAULT "r19: %08lx r18: %08lx r17: %08lx r16: %08lx\n",
regs->UCreg_19, regs->UCreg_18,
regs->UCreg_17, regs->UCreg_16);
printk(KERN_DEFAULT "r15: %08lx r14: %08lx r13: %08lx r12: %08lx\n",
regs->UCreg_15, regs->UCreg_14,
regs->UCreg_13, regs->UCreg_12);
printk(KERN_DEFAULT "r11: %08lx r10: %08lx r9 : %08lx r8 : %08lx\n",
regs->UCreg_11, regs->UCreg_10,
regs->UCreg_09, regs->UCreg_08);
printk(KERN_DEFAULT "r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
regs->UCreg_07, regs->UCreg_06,
regs->UCreg_05, regs->UCreg_04);
printk(KERN_DEFAULT "r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
regs->UCreg_03, regs->UCreg_02,
regs->UCreg_01, regs->UCreg_00);
flags = regs->UCreg_asr;
buf[0] = flags & PSR_S_BIT ? 'S' : 's';
buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
buf[4] = '\0';
printk(KERN_DEFAULT "Flags: %s INTR o%s REAL o%s Mode %s Segment %s\n",
buf, interrupts_enabled(regs) ? "n" : "ff",
fast_interrupts_enabled(regs) ? "n" : "ff",
processor_modes[processor_mode(regs)],
segment_eq(get_fs(), get_ds()) ? "kernel" : "user");
{
unsigned int ctrl;
buf[0] = '\0';
{
unsigned int transbase;
asm("movc %0, p0.c2, #0\n"
: "=r" (transbase));
snprintf(buf, sizeof(buf), " Table: %08x", transbase);
}
asm("movc %0, p0.c1, #0\n" : "=r" (ctrl));
printk(KERN_DEFAULT "Control: %08x%s\n", ctrl, buf);
}
}
void show_regs(struct pt_regs *regs)
{
printk(KERN_DEFAULT "\n");
printk(KERN_DEFAULT "Pid: %d, comm: %20s\n",
task_pid_nr(current), current->comm);
__show_regs(regs);
__backtrace();
}
/*
* Free current thread data structures etc..
*/
void exit_thread(void)
{
}
void flush_thread(void)
{
struct thread_info *thread = current_thread_info();
struct task_struct *tsk = current;
memset(thread->used_cp, 0, sizeof(thread->used_cp));
memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
#ifdef CONFIG_UNICORE_FPU_F64
memset(&thread->fpstate, 0, sizeof(struct fp_state));
#endif
}
void release_thread(struct task_struct *dead_task)
{
}
asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
asmlinkage void ret_from_kernel_thread(void) __asm__("ret_from_kernel_thread");
int
copy_thread(unsigned long clone_flags, unsigned long stack_start,
unsigned long stk_sz, struct task_struct *p)
{
struct thread_info *thread = task_thread_info(p);
struct pt_regs *childregs = task_pt_regs(p);
memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
thread->cpu_context.sp = (unsigned long)childregs;
if (unlikely(p->flags & PF_KTHREAD)) {
thread->cpu_context.pc = (unsigned long)ret_from_kernel_thread;
thread->cpu_context.r4 = stack_start;
thread->cpu_context.r5 = stk_sz;
memset(childregs, 0, sizeof(struct pt_regs));
} else {
thread->cpu_context.pc = (unsigned long)ret_from_fork;
*childregs = *current_pt_regs();
childregs->UCreg_00 = 0;
if (stack_start)
childregs->UCreg_sp = stack_start;
if (clone_flags & CLONE_SETTLS)
childregs->UCreg_16 = childregs->UCreg_03;
}
return 0;
}
/*
* Fill in the task's elfregs structure for a core dump.
*/
int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs)
{
elf_core_copy_regs(elfregs, task_pt_regs(t));
return 1;
}
/*
* fill in the fpe structure for a core dump...
*/
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fp)
{
struct thread_info *thread = current_thread_info();
int used_math = thread->used_cp[1] | thread->used_cp[2];
#ifdef CONFIG_UNICORE_FPU_F64
if (used_math)
memcpy(fp, &thread->fpstate, sizeof(*fp));
#endif
return used_math != 0;
}
EXPORT_SYMBOL(dump_fpu);
unsigned long get_wchan(struct task_struct *p)
{
struct stackframe frame;
int count = 0;
if (!p || p == current || p->state == TASK_RUNNING)
return 0;
frame.fp = thread_saved_fp(p);
frame.sp = thread_saved_sp(p);
frame.lr = 0; /* recovered from the stack */
frame.pc = thread_saved_pc(p);
do {
int ret = unwind_frame(&frame);
if (ret < 0)
return 0;
if (!in_sched_functions(frame.pc))
return frame.pc;
} while ((count++) < 16);
return 0;
}
unsigned long arch_randomize_brk(struct mm_struct *mm)
{
unsigned long range_end = mm->brk + 0x02000000;
return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
}
/*
* The vectors page is always readable from user space for the
* atomic helpers and the signal restart code. Let's declare a mapping
* for it so it is visible through ptrace and /proc/<pid>/mem.
*/
int vectors_user_mapping(void)
{
struct mm_struct *mm = current->mm;
return install_special_mapping(mm, 0xffff0000, PAGE_SIZE,
VM_READ | VM_EXEC |
VM_MAYREAD | VM_MAYEXEC |
VM_DONTEXPAND | VM_DONTDUMP,
NULL);
}
const char *arch_vma_name(struct vm_area_struct *vma)
{
return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL;
}