| /* |
| * File: arch/blackfin/kernel/process.c |
| * Based on: |
| * Author: |
| * |
| * Created: |
| * Description: Blackfin architecture-dependent process handling. |
| * |
| * Modified: |
| * Copyright 2004-2006 Analog Devices Inc. |
| * |
| * Bugs: Enter bugs at http://blackfin.uclinux.org/ |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, see the file COPYING, or write |
| * to the Free Software Foundation, Inc., |
| * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/smp_lock.h> |
| #include <linux/unistd.h> |
| #include <linux/user.h> |
| #include <linux/a.out.h> |
| |
| #include <asm/blackfin.h> |
| #include <asm/uaccess.h> |
| |
| #define LED_ON 0 |
| #define LED_OFF 1 |
| |
| asmlinkage void ret_from_fork(void); |
| |
| /* Points to the SDRAM backup memory for the stack that is currently in |
| * L1 scratchpad memory. |
| */ |
| void *current_l1_stack_save; |
| |
| /* The number of tasks currently using a L1 stack area. The SRAM is |
| * allocated/deallocated whenever this changes from/to zero. |
| */ |
| int nr_l1stack_tasks; |
| |
| /* Start and length of the area in L1 scratchpad memory which we've allocated |
| * for process stacks. |
| */ |
| void *l1_stack_base; |
| unsigned long l1_stack_len; |
| |
| /* |
| * Powermanagement idle function, if any.. |
| */ |
| void (*pm_idle)(void) = NULL; |
| EXPORT_SYMBOL(pm_idle); |
| |
| void (*pm_power_off)(void) = NULL; |
| EXPORT_SYMBOL(pm_power_off); |
| |
| /* |
| * We are using a different LED from the one used to indicate timer interrupt. |
| */ |
| #if defined(CONFIG_BFIN_IDLE_LED) |
| static inline void leds_switch(int flag) |
| { |
| unsigned short tmp = 0; |
| |
| tmp = bfin_read_CONFIG_BFIN_IDLE_LED_PORT(); |
| SSYNC(); |
| |
| if (flag == LED_ON) |
| tmp &= ~CONFIG_BFIN_IDLE_LED_PIN; /* light on */ |
| else |
| tmp |= CONFIG_BFIN_IDLE_LED_PIN; /* light off */ |
| |
| bfin_write_CONFIG_BFIN_IDLE_LED_PORT(tmp); |
| SSYNC(); |
| |
| } |
| #else |
| static inline void leds_switch(int flag) |
| { |
| } |
| #endif |
| |
| /* |
| * The idle loop on BFIN |
| */ |
| #ifdef CONFIG_IDLE_L1 |
| void default_idle(void)__attribute__((l1_text)); |
| void cpu_idle(void)__attribute__((l1_text)); |
| #endif |
| |
| void default_idle(void) |
| { |
| while (!need_resched()) { |
| leds_switch(LED_OFF); |
| local_irq_disable(); |
| if (likely(!need_resched())) |
| idle_with_irq_disabled(); |
| local_irq_enable(); |
| leds_switch(LED_ON); |
| } |
| } |
| |
| void (*idle)(void) = default_idle; |
| |
| /* |
| * The idle thread. There's no useful work to be |
| * done, so just try to conserve power and have a |
| * low exit latency (ie sit in a loop waiting for |
| * somebody to say that they'd like to reschedule) |
| */ |
| void cpu_idle(void) |
| { |
| /* endless idle loop with no priority at all */ |
| while (1) { |
| idle(); |
| preempt_enable_no_resched(); |
| schedule(); |
| preempt_disable(); |
| } |
| } |
| |
| void machine_restart(char *__unused) |
| { |
| #if defined(CONFIG_BLKFIN_CACHE) |
| bfin_write_IMEM_CONTROL(0x01); |
| SSYNC(); |
| #endif |
| bfin_reset(); |
| /* Dont do anything till the reset occurs */ |
| while (1) { |
| SSYNC(); |
| } |
| } |
| |
| void machine_halt(void) |
| { |
| for (;;) |
| asm volatile ("idle"); |
| } |
| |
| void machine_power_off(void) |
| { |
| for (;;) |
| asm volatile ("idle"); |
| } |
| |
| void show_regs(struct pt_regs *regs) |
| { |
| printk(KERN_NOTICE "\n"); |
| printk(KERN_NOTICE |
| "PC: %08lu Status: %04lu SysStatus: %04lu RETS: %08lu\n", |
| regs->pc, regs->astat, regs->seqstat, regs->rets); |
| printk(KERN_NOTICE |
| "A0.x: %08lx A0.w: %08lx A1.x: %08lx A1.w: %08lx\n", |
| regs->a0x, regs->a0w, regs->a1x, regs->a1w); |
| printk(KERN_NOTICE "P0: %08lx P1: %08lx P2: %08lx P3: %08lx\n", |
| regs->p0, regs->p1, regs->p2, regs->p3); |
| printk(KERN_NOTICE "P4: %08lx P5: %08lx\n", regs->p4, regs->p5); |
| printk(KERN_NOTICE "R0: %08lx R1: %08lx R2: %08lx R3: %08lx\n", |
| regs->r0, regs->r1, regs->r2, regs->r3); |
| printk(KERN_NOTICE "R4: %08lx R5: %08lx R6: %08lx R7: %08lx\n", |
| regs->r4, regs->r5, regs->r6, regs->r7); |
| |
| if (!(regs->ipend)) |
| printk("USP: %08lx\n", rdusp()); |
| } |
| |
| /* Fill in the fpu structure for a core dump. */ |
| |
| int dump_fpu(struct pt_regs *regs, elf_fpregset_t * fpregs) |
| { |
| return 1; |
| } |
| |
| /* |
| * This gets run with P1 containing the |
| * function to call, and R1 containing |
| * the "args". Note P0 is clobbered on the way here. |
| */ |
| void kernel_thread_helper(void); |
| __asm__(".section .text\n" |
| ".align 4\n" |
| "_kernel_thread_helper:\n\t" |
| "\tsp += -12;\n\t" |
| "\tr0 = r1;\n\t" "\tcall (p1);\n\t" "\tcall _do_exit;\n" ".previous"); |
| |
| /* |
| * Create a kernel thread. |
| */ |
| pid_t kernel_thread(int (*fn) (void *), void *arg, unsigned long flags) |
| { |
| struct pt_regs regs; |
| |
| memset(®s, 0, sizeof(regs)); |
| |
| regs.r1 = (unsigned long)arg; |
| regs.p1 = (unsigned long)fn; |
| regs.pc = (unsigned long)kernel_thread_helper; |
| regs.orig_p0 = -1; |
| /* Set bit 2 to tell ret_from_fork we should be returning to kernel |
| mode. */ |
| regs.ipend = 0x8002; |
| __asm__ __volatile__("%0 = syscfg;":"=da"(regs.syscfg):); |
| return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s, 0, NULL, |
| NULL); |
| } |
| |
| void flush_thread(void) |
| { |
| } |
| |
| asmlinkage int bfin_vfork(struct pt_regs *regs) |
| { |
| return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0, NULL, |
| NULL); |
| } |
| |
| asmlinkage int bfin_clone(struct pt_regs *regs) |
| { |
| unsigned long clone_flags; |
| unsigned long newsp; |
| |
| /* syscall2 puts clone_flags in r0 and usp in r1 */ |
| clone_flags = regs->r0; |
| newsp = regs->r1; |
| if (!newsp) |
| newsp = rdusp(); |
| else |
| newsp -= 12; |
| return do_fork(clone_flags, newsp, regs, 0, NULL, NULL); |
| } |
| |
| int |
| copy_thread(int nr, unsigned long clone_flags, |
| unsigned long usp, unsigned long topstk, |
| struct task_struct *p, struct pt_regs *regs) |
| { |
| struct pt_regs *childregs; |
| |
| childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1; |
| *childregs = *regs; |
| childregs->r0 = 0; |
| |
| p->thread.usp = usp; |
| p->thread.ksp = (unsigned long)childregs; |
| p->thread.pc = (unsigned long)ret_from_fork; |
| |
| return 0; |
| } |
| |
| /* |
| * fill in the user structure for a core dump.. |
| */ |
| void dump_thread(struct pt_regs *regs, struct user *dump) |
| { |
| dump->magic = CMAGIC; |
| dump->start_code = 0; |
| dump->start_stack = rdusp() & ~(PAGE_SIZE - 1); |
| dump->u_tsize = ((unsigned long)current->mm->end_code) >> PAGE_SHIFT; |
| dump->u_dsize = ((unsigned long)(current->mm->brk + |
| (PAGE_SIZE - 1))) >> PAGE_SHIFT; |
| dump->u_dsize -= dump->u_tsize; |
| dump->u_ssize = 0; |
| |
| if (dump->start_stack < TASK_SIZE) |
| dump->u_ssize = |
| ((unsigned long)(TASK_SIZE - |
| dump->start_stack)) >> PAGE_SHIFT; |
| |
| dump->u_ar0 = (struct user_regs_struct *)((int)&dump->regs - (int)dump); |
| |
| dump->regs.r0 = regs->r0; |
| dump->regs.r1 = regs->r1; |
| dump->regs.r2 = regs->r2; |
| dump->regs.r3 = regs->r3; |
| dump->regs.r4 = regs->r4; |
| dump->regs.r5 = regs->r5; |
| dump->regs.r6 = regs->r6; |
| dump->regs.r7 = regs->r7; |
| dump->regs.p0 = regs->p0; |
| dump->regs.p1 = regs->p1; |
| dump->regs.p2 = regs->p2; |
| dump->regs.p3 = regs->p3; |
| dump->regs.p4 = regs->p4; |
| dump->regs.p5 = regs->p5; |
| dump->regs.orig_p0 = regs->orig_p0; |
| dump->regs.a0w = regs->a0w; |
| dump->regs.a1w = regs->a1w; |
| dump->regs.a0x = regs->a0x; |
| dump->regs.a1x = regs->a1x; |
| dump->regs.rets = regs->rets; |
| dump->regs.astat = regs->astat; |
| dump->regs.pc = regs->pc; |
| } |
| |
| /* |
| * sys_execve() executes a new program. |
| */ |
| |
| asmlinkage int sys_execve(char *name, char **argv, char **envp) |
| { |
| int error; |
| char *filename; |
| struct pt_regs *regs = (struct pt_regs *)((&name) + 6); |
| |
| lock_kernel(); |
| filename = getname(name); |
| error = PTR_ERR(filename); |
| if (IS_ERR(filename)) |
| goto out; |
| error = do_execve(filename, argv, envp, regs); |
| putname(filename); |
| out: |
| unlock_kernel(); |
| return error; |
| } |
| |
| unsigned long get_wchan(struct task_struct *p) |
| { |
| unsigned long fp, pc; |
| unsigned long stack_page; |
| int count = 0; |
| if (!p || p == current || p->state == TASK_RUNNING) |
| return 0; |
| |
| stack_page = (unsigned long)p; |
| fp = p->thread.usp; |
| do { |
| if (fp < stack_page + sizeof(struct thread_info) || |
| fp >= 8184 + stack_page) |
| return 0; |
| pc = ((unsigned long *)fp)[1]; |
| if (!in_sched_functions(pc)) |
| return pc; |
| fp = *(unsigned long *)fp; |
| } |
| while (count++ < 16); |
| return 0; |
| } |
| |
| #if defined(CONFIG_ACCESS_CHECK) |
| int _access_ok(unsigned long addr, unsigned long size) |
| { |
| |
| if (addr > (addr + size)) |
| return 0; |
| if (segment_eq(get_fs(),KERNEL_DS)) |
| return 1; |
| #ifdef CONFIG_MTD_UCLINUX |
| if (addr >= memory_start && (addr + size) <= memory_end) |
| return 1; |
| if (addr >= memory_mtd_end && (addr + size) <= physical_mem_end) |
| return 1; |
| #else |
| if (addr >= memory_start && (addr + size) <= physical_mem_end) |
| return 1; |
| #endif |
| if (addr >= (unsigned long)__init_begin && |
| addr + size <= (unsigned long)__init_end) |
| return 1; |
| if (addr >= L1_SCRATCH_START |
| && addr + size <= L1_SCRATCH_START + L1_SCRATCH_LENGTH) |
| return 1; |
| #if L1_CODE_LENGTH != 0 |
| if (addr >= L1_CODE_START + (_etext_l1 - _stext_l1) |
| && addr + size <= L1_CODE_START + L1_CODE_LENGTH) |
| return 1; |
| #endif |
| #if L1_DATA_A_LENGTH != 0 |
| if (addr >= L1_DATA_A_START + (_ebss_l1 - _sdata_l1) |
| && addr + size <= L1_DATA_A_START + L1_DATA_A_LENGTH) |
| return 1; |
| #endif |
| #if L1_DATA_B_LENGTH != 0 |
| if (addr >= L1_DATA_B_START |
| && addr + size <= L1_DATA_B_START + L1_DATA_B_LENGTH) |
| return 1; |
| #endif |
| return 0; |
| } |
| EXPORT_SYMBOL(_access_ok); |
| #endif /* CONFIG_ACCESS_CHECK */ |