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Diffstat (limited to 'arch/blackfin/kernel/process.c')
| -rw-r--r-- | arch/blackfin/kernel/process.c | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/process.c b/arch/blackfin/kernel/process.c new file mode 100644 index 00000000000..3eff7439d8d --- /dev/null +++ b/arch/blackfin/kernel/process.c @@ -0,0 +1,394 @@ +/* + * 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 */ |