| /* |
| * Blackfin architecture-dependent process handling |
| * |
| * Copyright 2004-2009 Analog Devices Inc. |
| * |
| * Licensed under the GPL-2 or later |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/unistd.h> |
| #include <linux/user.h> |
| #include <linux/uaccess.h> |
| #include <linux/slab.h> |
| #include <linux/sched.h> |
| #include <linux/sched/debug.h> |
| #include <linux/sched/task.h> |
| #include <linux/sched/task_stack.h> |
| #include <linux/mm_types.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> |
| #include <asm/irq.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; |
| |
| void (*pm_power_off)(void) = NULL; |
| EXPORT_SYMBOL(pm_power_off); |
| |
| /* |
| * The idle loop on BFIN |
| */ |
| #ifdef CONFIG_IDLE_L1 |
| void arch_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. |
| */ |
| void arch_cpu_idle(void) |
| { |
| #ifdef CONFIG_IPIPE |
| ipipe_suspend_domain(); |
| #endif |
| hard_local_irq_disable(); |
| if (!need_resched()) |
| idle_with_irq_disabled(); |
| |
| hard_local_irq_enable(); |
| } |
| |
| #ifdef CONFIG_HOTPLUG_CPU |
| void arch_cpu_idle_dead(void) |
| { |
| cpu_die(); |
| } |
| #endif |
| |
| /* |
| * 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) |
| { |
| regs->pc = new_ip; |
| if (current->mm) |
| regs->p5 = current->mm->start_data; |
| #ifndef 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_clone(unsigned long clone_flags, unsigned long newsp) |
| { |
| #ifdef __ARCH_SYNC_CORE_DCACHE |
| if (current->nr_cpus_allowed == num_possible_cpus()) |
| set_cpus_allowed_ptr(current, cpumask_of(smp_processor_id())); |
| #endif |
| if (newsp) |
| newsp -= 12; |
| return do_fork(clone_flags, newsp, 0, NULL, NULL); |
| } |
| |
| int |
| copy_thread(unsigned long clone_flags, |
| unsigned long usp, unsigned long topstk, |
| struct task_struct *p) |
| { |
| struct pt_regs *childregs; |
| unsigned long *v; |
| |
| childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1; |
| v = ((unsigned long *)childregs) - 2; |
| if (unlikely(p->flags & PF_KTHREAD)) { |
| memset(childregs, 0, sizeof(struct pt_regs)); |
| v[0] = usp; |
| v[1] = topstk; |
| childregs->orig_p0 = -1; |
| childregs->ipend = 0x8000; |
| __asm__ __volatile__("%0 = syscfg;":"=da"(childregs->syscfg):); |
| p->thread.usp = 0; |
| } else { |
| *childregs = *current_pt_regs(); |
| childregs->r0 = 0; |
| p->thread.usp = usp ? : rdusp(); |
| v[0] = v[1] = 0; |
| } |
| |
| p->thread.ksp = (unsigned long)v; |
| p->thread.pc = (unsigned long)ret_from_fork; |
| |
| return 0; |
| } |
| |
| 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) { |
| default: |
| /* not in middle of an atomic step, so resume like normal */ |
| return; |
| |
| case ATOMIC_XCHG32 + 2: |
| put_user(regs->r1, up0); |
| break; |
| |
| case ATOMIC_CAS32 + 2: |
| case ATOMIC_CAS32 + 4: |
| if (regs->r0 == regs->r1) |
| case ATOMIC_CAS32 + 6: |
| put_user(regs->r2, up0); |
| break; |
| |
| case ATOMIC_ADD32 + 2: |
| regs->r0 = regs->r1 + regs->r0; |
| /* fall through */ |
| case ATOMIC_ADD32 + 4: |
| put_user(regs->r0, up0); |
| break; |
| |
| case ATOMIC_SUB32 + 2: |
| regs->r0 = regs->r1 - regs->r0; |
| /* fall through */ |
| case ATOMIC_SUB32 + 4: |
| put_user(regs->r0, up0); |
| break; |
| |
| case ATOMIC_IOR32 + 2: |
| regs->r0 = regs->r1 | regs->r0; |
| /* fall through */ |
| case ATOMIC_IOR32 + 4: |
| put_user(regs->r0, up0); |
| break; |
| |
| case ATOMIC_AND32 + 2: |
| regs->r0 = regs->r1 & regs->r0; |
| /* fall through */ |
| case ATOMIC_AND32 + 4: |
| put_user(regs->r0, up0); |
| break; |
| |
| case ATOMIC_XOR32 + 2: |
| regs->r0 = regs->r1 ^ regs->r0; |
| /* fall through */ |
| case ATOMIC_XOR32 + 4: |
| put_user(regs->r0, up0); |
| break; |
| } |
| |
| /* |
| * We've finished the atomic section, and the only thing left for |
| * userspace is to do a RTS, so we might as well handle that too |
| * since we need to update the PC anyways. |
| */ |
| regs->pc = regs->rets; |
| } |
| |
| 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); |
| } |
| #ifdef CONFIG_BF60x |
| #define ASYNC_ENABLED(bnum, bctlnum) 1 |
| #else |
| #define ASYNC_ENABLED(bnum, bctlnum) \ |
| ({ \ |
| (bfin_read_EBIU_AMGCTL() & 0xe) < ((bnum + 1) << 1) ? 0 : \ |
| bfin_read_EBIU_AMBCTL##bctlnum() & B##bnum##RDYEN ? 0 : \ |
| 1; \ |
| }) |
| #endif |
| /* |
| * We can't read EBIU banks that aren't enabled or we end up hanging |
| * on the access to the async space. Make sure we validate accesses |
| * that cross async banks too. |
| * 0 - found, but unusable |
| * 1 - found & usable |
| * 2 - not found |
| */ |
| static |
| int in_async(unsigned long addr, unsigned long size) |
| { |
| if (addr >= ASYNC_BANK0_BASE && addr < ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE) { |
| if (!ASYNC_ENABLED(0, 0)) |
| return 0; |
| if (addr + size <= ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE) |
| return 1; |
| size -= ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE - addr; |
| addr = ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE; |
| } |
| if (addr >= ASYNC_BANK1_BASE && addr < ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE) { |
| if (!ASYNC_ENABLED(1, 0)) |
| return 0; |
| if (addr + size <= ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE) |
| return 1; |
| size -= ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE - addr; |
| addr = ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE; |
| } |
| if (addr >= ASYNC_BANK2_BASE && addr < ASYNC_BANK2_BASE + ASYNC_BANK2_SIZE) { |
| if (!ASYNC_ENABLED(2, 1)) |
| return 0; |
| if (addr + size <= ASYNC_BANK2_BASE + ASYNC_BANK2_SIZE) |
| return 1; |
| size -= ASYNC_BANK2_BASE + ASYNC_BANK2_SIZE - addr; |
| addr = ASYNC_BANK2_BASE + ASYNC_BANK2_SIZE; |
| } |
| if (addr >= ASYNC_BANK3_BASE && addr < ASYNC_BANK3_BASE + ASYNC_BANK3_SIZE) { |
| if (ASYNC_ENABLED(3, 1)) |
| return 0; |
| if (addr + size <= ASYNC_BANK3_BASE + ASYNC_BANK3_SIZE) |
| return 1; |
| return 0; |
| } |
| |
| /* not within async bounds */ |
| return 2; |
| } |
| |
| 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; |
| |
| switch (in_async(addr, size)) { |
| case 0: return -EFAULT; |
| case 1: return BFIN_MEM_ACCESS_CORE; |
| case 2: /* fall through */; |
| } |
| |
| 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) |
| { |
| int aret; |
| |
| if (size == 0) |
| return 1; |
| /* Check that things do not wrap around */ |
| if (addr > ULONG_MAX - size) |
| return 0; |
| if (uaccess_kernel()) |
| 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 |
| |
| #ifndef CONFIG_EXCEPTION_L1_SCRATCH |
| if (in_mem_const(addr, size, (unsigned long)l1_stack_base, l1_stack_len)) |
| return 1; |
| #endif |
| |
| aret = in_async(addr, size); |
| if (aret < 2) |
| return aret; |
| |
| 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 */ |