| /* |
| * Blackfin architecture-dependent process handling |
| * |
| * Copyright 2004-2009 Analog Devices Inc. |
| * |
| * Licensed under the GPL-2 or later |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/smp_lock.h> |
| #include <linux/unistd.h> |
| #include <linux/user.h> |
| #include <linux/uaccess.h> |
| #include <linux/sched.h> |
| #include <linux/tick.h> |
| #include <linux/fs.h> |
| #include <linux/err.h> |
| |
| #include <asm/blackfin.h> |
| #include <asm/fixed_code.h> |
| #include <asm/mem_map.h> |
| |
| 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); |
| |
| /* |
| * The idle loop on BFIN |
| */ |
| #ifdef CONFIG_IDLE_L1 |
| static void default_idle(void)__attribute__((l1_text)); |
| void cpu_idle(void)__attribute__((l1_text)); |
| #endif |
| |
| /* |
| * This is our default idle handler. We need to disable |
| * interrupts here to ensure we don't miss a wakeup call. |
| */ |
| static void default_idle(void) |
| { |
| #ifdef CONFIG_IPIPE |
| ipipe_suspend_domain(); |
| #endif |
| local_irq_disable_hw(); |
| if (!need_resched()) |
| idle_with_irq_disabled(); |
| |
| local_irq_enable_hw(); |
| } |
| |
| /* |
| * The idle thread. We try to conserve power, while trying to keep |
| * overall latency low. The architecture specific idle is passed |
| * a value to indicate the level of "idleness" of the system. |
| */ |
| void cpu_idle(void) |
| { |
| /* endless idle loop with no priority at all */ |
| while (1) { |
| void (*idle)(void) = pm_idle; |
| |
| #ifdef CONFIG_HOTPLUG_CPU |
| if (cpu_is_offline(smp_processor_id())) |
| cpu_die(); |
| #endif |
| if (!idle) |
| idle = default_idle; |
| tick_nohz_stop_sched_tick(1); |
| while (!need_resched()) |
| idle(); |
| tick_nohz_restart_sched_tick(); |
| preempt_enable_no_resched(); |
| schedule(); |
| preempt_disable(); |
| } |
| } |
| |
| /* 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); |
| } |
| EXPORT_SYMBOL(kernel_thread); |
| |
| /* |
| * Do necessary setup to start up a newly executed thread. |
| * |
| * pass the data segment into user programs if it exists, |
| * it can't hurt anything as far as I can tell |
| */ |
| void start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp) |
| { |
| set_fs(USER_DS); |
| regs->pc = new_ip; |
| if (current->mm) |
| regs->p5 = current->mm->start_data; |
| #ifdef CONFIG_SMP |
| task_thread_info(current)->l1_task_info.stack_start = |
| (void *)current->mm->context.stack_start; |
| task_thread_info(current)->l1_task_info.lowest_sp = (void *)new_sp; |
| memcpy(L1_SCRATCH_TASK_INFO, &task_thread_info(current)->l1_task_info, |
| sizeof(*L1_SCRATCH_TASK_INFO)); |
| #endif |
| wrusp(new_sp); |
| } |
| EXPORT_SYMBOL_GPL(start_thread); |
| |
| 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; |
| |
| #ifdef __ARCH_SYNC_CORE_DCACHE |
| if (current->rt.nr_cpus_allowed == num_possible_cpus()) { |
| current->cpus_allowed = cpumask_of_cpu(smp_processor_id()); |
| current->rt.nr_cpus_allowed = 1; |
| } |
| #endif |
| |
| /* 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(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; |
| } |
| |
| /* |
| * sys_execve() executes a new program. |
| */ |
| |
| asmlinkage int sys_execve(char __user *name, char __user * __user *argv, char __user * __user *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; |
| } |
| |
| void finish_atomic_sections (struct pt_regs *regs) |
| { |
| int __user *up0 = (int __user *)regs->p0; |
| |
| switch (regs->pc) { |
| case ATOMIC_XCHG32 + 2: |
| put_user(regs->r1, up0); |
| regs->pc = ATOMIC_XCHG32 + 4; |
| break; |
| |
| case ATOMIC_CAS32 + 2: |
| case ATOMIC_CAS32 + 4: |
| if (regs->r0 == regs->r1) |
| case ATOMIC_CAS32 + 6: |
| put_user(regs->r2, up0); |
| regs->pc = ATOMIC_CAS32 + 8; |
| break; |
| |
| case ATOMIC_ADD32 + 2: |
| regs->r0 = regs->r1 + regs->r0; |
| /* fall through */ |
| case ATOMIC_ADD32 + 4: |
| put_user(regs->r0, up0); |
| regs->pc = ATOMIC_ADD32 + 6; |
| break; |
| |
| case ATOMIC_SUB32 + 2: |
| regs->r0 = regs->r1 - regs->r0; |
| /* fall through */ |
| case ATOMIC_SUB32 + 4: |
| put_user(regs->r0, up0); |
| regs->pc = ATOMIC_SUB32 + 6; |
| break; |
| |
| case ATOMIC_IOR32 + 2: |
| regs->r0 = regs->r1 | regs->r0; |
| /* fall through */ |
| case ATOMIC_IOR32 + 4: |
| put_user(regs->r0, up0); |
| regs->pc = ATOMIC_IOR32 + 6; |
| break; |
| |
| case ATOMIC_AND32 + 2: |
| regs->r0 = regs->r1 & regs->r0; |
| /* fall through */ |
| case ATOMIC_AND32 + 4: |
| put_user(regs->r0, up0); |
| regs->pc = ATOMIC_AND32 + 6; |
| break; |
| |
| case ATOMIC_XOR32 + 2: |
| regs->r0 = regs->r1 ^ regs->r0; |
| /* fall through */ |
| case ATOMIC_XOR32 + 4: |
| put_user(regs->r0, up0); |
| regs->pc = ATOMIC_XOR32 + 6; |
| break; |
| } |
| } |
| |
| static inline |
| int in_mem(unsigned long addr, unsigned long size, |
| unsigned long start, unsigned long end) |
| { |
| return addr >= start && addr + size <= end; |
| } |
| static inline |
| int in_mem_const_off(unsigned long addr, unsigned long size, unsigned long off, |
| unsigned long const_addr, unsigned long const_size) |
| { |
| return const_size && |
| in_mem(addr, size, const_addr + off, const_addr + const_size); |
| } |
| static inline |
| int in_mem_const(unsigned long addr, unsigned long size, |
| unsigned long const_addr, unsigned long const_size) |
| { |
| return in_mem_const_off(addr, size, 0, const_addr, const_size); |
| } |
| #define IN_ASYNC(bnum, bctlnum) \ |
| ({ \ |
| (bfin_read_EBIU_AMGCTL() & 0xe) < ((bnum + 1) << 1) ? -EFAULT : \ |
| bfin_read_EBIU_AMBCTL##bctlnum() & B##bnum##RDYEN ? -EFAULT : \ |
| BFIN_MEM_ACCESS_CORE; \ |
| }) |
| |
| int bfin_mem_access_type(unsigned long addr, unsigned long size) |
| { |
| int cpu = raw_smp_processor_id(); |
| |
| /* Check that things do not wrap around */ |
| if (addr > ULONG_MAX - size) |
| return -EFAULT; |
| |
| if (in_mem(addr, size, FIXED_CODE_START, physical_mem_end)) |
| return BFIN_MEM_ACCESS_CORE; |
| |
| if (in_mem_const(addr, size, L1_CODE_START, L1_CODE_LENGTH)) |
| return cpu == 0 ? BFIN_MEM_ACCESS_ITEST : BFIN_MEM_ACCESS_IDMA; |
| if (in_mem_const(addr, size, L1_SCRATCH_START, L1_SCRATCH_LENGTH)) |
| return cpu == 0 ? BFIN_MEM_ACCESS_CORE_ONLY : -EFAULT; |
| if (in_mem_const(addr, size, L1_DATA_A_START, L1_DATA_A_LENGTH)) |
| return cpu == 0 ? BFIN_MEM_ACCESS_CORE : BFIN_MEM_ACCESS_IDMA; |
| if (in_mem_const(addr, size, L1_DATA_B_START, L1_DATA_B_LENGTH)) |
| return cpu == 0 ? BFIN_MEM_ACCESS_CORE : BFIN_MEM_ACCESS_IDMA; |
| #ifdef COREB_L1_CODE_START |
| if (in_mem_const(addr, size, COREB_L1_CODE_START, COREB_L1_CODE_LENGTH)) |
| return cpu == 1 ? BFIN_MEM_ACCESS_ITEST : BFIN_MEM_ACCESS_IDMA; |
| if (in_mem_const(addr, size, COREB_L1_SCRATCH_START, L1_SCRATCH_LENGTH)) |
| return cpu == 1 ? BFIN_MEM_ACCESS_CORE_ONLY : -EFAULT; |
| if (in_mem_const(addr, size, COREB_L1_DATA_A_START, COREB_L1_DATA_A_LENGTH)) |
| return cpu == 1 ? BFIN_MEM_ACCESS_CORE : BFIN_MEM_ACCESS_IDMA; |
| if (in_mem_const(addr, size, COREB_L1_DATA_B_START, COREB_L1_DATA_B_LENGTH)) |
| return cpu == 1 ? BFIN_MEM_ACCESS_CORE : BFIN_MEM_ACCESS_IDMA; |
| #endif |
| if (in_mem_const(addr, size, L2_START, L2_LENGTH)) |
| return BFIN_MEM_ACCESS_CORE; |
| |
| if (addr >= SYSMMR_BASE) |
| return BFIN_MEM_ACCESS_CORE_ONLY; |
| |
| /* We can't read EBIU banks that aren't enabled or we end up hanging |
| * on the access to the async space. |
| */ |
| if (in_mem_const(addr, size, ASYNC_BANK0_BASE, ASYNC_BANK0_SIZE)) |
| return IN_ASYNC(0, 0); |
| if (in_mem_const(addr, size, ASYNC_BANK1_BASE, ASYNC_BANK1_SIZE)) |
| return IN_ASYNC(1, 0); |
| if (in_mem_const(addr, size, ASYNC_BANK2_BASE, ASYNC_BANK2_SIZE)) |
| return IN_ASYNC(2, 1); |
| if (in_mem_const(addr, size, ASYNC_BANK3_BASE, ASYNC_BANK3_SIZE)) |
| return IN_ASYNC(3, 1); |
| |
| if (in_mem_const(addr, size, BOOT_ROM_START, BOOT_ROM_LENGTH)) |
| return BFIN_MEM_ACCESS_CORE; |
| if (in_mem_const(addr, size, L1_ROM_START, L1_ROM_LENGTH)) |
| return BFIN_MEM_ACCESS_DMA; |
| |
| return -EFAULT; |
| } |
| |
| #if defined(CONFIG_ACCESS_CHECK) |
| #ifdef CONFIG_ACCESS_OK_L1 |
| __attribute__((l1_text)) |
| #endif |
| /* Return 1 if access to memory range is OK, 0 otherwise */ |
| int _access_ok(unsigned long addr, unsigned long size) |
| { |
| if (size == 0) |
| return 1; |
| /* Check that things do not wrap around */ |
| if (addr > ULONG_MAX - size) |
| return 0; |
| if (segment_eq(get_fs(), KERNEL_DS)) |
| return 1; |
| #ifdef CONFIG_MTD_UCLINUX |
| if (1) |
| #else |
| if (0) |
| #endif |
| { |
| if (in_mem(addr, size, memory_start, memory_end)) |
| return 1; |
| if (in_mem(addr, size, memory_mtd_end, physical_mem_end)) |
| return 1; |
| # ifndef CONFIG_ROMFS_ON_MTD |
| if (0) |
| # endif |
| /* For XIP, allow user space to use pointers within the ROMFS. */ |
| if (in_mem(addr, size, memory_mtd_start, memory_mtd_end)) |
| return 1; |
| } else { |
| if (in_mem(addr, size, memory_start, physical_mem_end)) |
| return 1; |
| } |
| |
| if (in_mem(addr, size, (unsigned long)__init_begin, (unsigned long)__init_end)) |
| return 1; |
| |
| if (in_mem_const(addr, size, L1_CODE_START, L1_CODE_LENGTH)) |
| return 1; |
| if (in_mem_const_off(addr, size, _etext_l1 - _stext_l1, L1_CODE_START, L1_CODE_LENGTH)) |
| return 1; |
| if (in_mem_const_off(addr, size, _ebss_l1 - _sdata_l1, L1_DATA_A_START, L1_DATA_A_LENGTH)) |
| return 1; |
| if (in_mem_const_off(addr, size, _ebss_b_l1 - _sdata_b_l1, L1_DATA_B_START, L1_DATA_B_LENGTH)) |
| return 1; |
| #ifdef COREB_L1_CODE_START |
| if (in_mem_const(addr, size, COREB_L1_CODE_START, COREB_L1_CODE_LENGTH)) |
| return 1; |
| if (in_mem_const(addr, size, COREB_L1_SCRATCH_START, L1_SCRATCH_LENGTH)) |
| return 1; |
| if (in_mem_const(addr, size, COREB_L1_DATA_A_START, COREB_L1_DATA_A_LENGTH)) |
| return 1; |
| if (in_mem_const(addr, size, COREB_L1_DATA_B_START, COREB_L1_DATA_B_LENGTH)) |
| return 1; |
| #endif |
| if (in_mem_const_off(addr, size, _ebss_l2 - _stext_l2, L2_START, L2_LENGTH)) |
| return 1; |
| |
| if (in_mem_const(addr, size, BOOT_ROM_START, BOOT_ROM_LENGTH)) |
| return 1; |
| if (in_mem_const(addr, size, L1_ROM_START, L1_ROM_LENGTH)) |
| return 1; |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(_access_ok); |
| #endif /* CONFIG_ACCESS_CHECK */ |