2 * Blackfin architecture-dependent process handling
4 * Copyright 2004-2009 Analog Devices Inc.
6 * Licensed under the GPL-2 or later
9 #include <linux/module.h>
10 #include <linux/unistd.h>
11 #include <linux/user.h>
12 #include <linux/uaccess.h>
13 #include <linux/slab.h>
14 #include <linux/sched.h>
15 #include <linux/tick.h>
17 #include <linux/err.h>
19 #include <asm/blackfin.h>
20 #include <asm/fixed_code.h>
21 #include <asm/mem_map.h>
24 asmlinkage void ret_from_fork(void);
26 /* Points to the SDRAM backup memory for the stack that is currently in
27 * L1 scratchpad memory.
29 void *current_l1_stack_save;
31 /* The number of tasks currently using a L1 stack area. The SRAM is
32 * allocated/deallocated whenever this changes from/to zero.
36 /* Start and length of the area in L1 scratchpad memory which we've allocated
40 unsigned long l1_stack_len;
43 * Powermanagement idle function, if any..
45 void (*pm_idle)(void) = NULL;
46 EXPORT_SYMBOL(pm_idle);
48 void (*pm_power_off)(void) = NULL;
49 EXPORT_SYMBOL(pm_power_off);
52 * The idle loop on BFIN
55 static void default_idle(void)__attribute__((l1_text));
56 void cpu_idle(void)__attribute__((l1_text));
60 * This is our default idle handler. We need to disable
61 * interrupts here to ensure we don't miss a wakeup call.
63 static void default_idle(void)
66 ipipe_suspend_domain();
68 hard_local_irq_disable();
70 idle_with_irq_disabled();
72 hard_local_irq_enable();
76 * The idle thread. We try to conserve power, while trying to keep
77 * overall latency low. The architecture specific idle is passed
78 * a value to indicate the level of "idleness" of the system.
82 /* endless idle loop with no priority at all */
84 void (*idle)(void) = pm_idle;
86 #ifdef CONFIG_HOTPLUG_CPU
87 if (cpu_is_offline(smp_processor_id()))
92 tick_nohz_idle_enter();
94 while (!need_resched())
97 tick_nohz_idle_exit();
98 schedule_preempt_disabled();
103 * This gets run with P1 containing the
104 * function to call, and R1 containing
105 * the "args". Note P0 is clobbered on the way here.
107 void kernel_thread_helper(void);
108 __asm__(".section .text\n"
110 "_kernel_thread_helper:\n\t"
112 "\tr0 = r1;\n\t" "\tcall (p1);\n\t" "\tcall _do_exit;\n" ".previous");
115 * Create a kernel thread.
117 pid_t kernel_thread(int (*fn) (void *), void *arg, unsigned long flags)
121 memset(®s, 0, sizeof(regs));
123 regs.r1 = (unsigned long)arg;
124 regs.p1 = (unsigned long)fn;
125 regs.pc = (unsigned long)kernel_thread_helper;
127 /* Set bit 2 to tell ret_from_fork we should be returning to kernel
130 __asm__ __volatile__("%0 = syscfg;":"=da"(regs.syscfg):);
131 return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s, 0, NULL,
134 EXPORT_SYMBOL(kernel_thread);
137 * Do necessary setup to start up a newly executed thread.
139 * pass the data segment into user programs if it exists,
140 * it can't hurt anything as far as I can tell
142 void start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
146 regs->p5 = current->mm->start_data;
148 task_thread_info(current)->l1_task_info.stack_start =
149 (void *)current->mm->context.stack_start;
150 task_thread_info(current)->l1_task_info.lowest_sp = (void *)new_sp;
151 memcpy(L1_SCRATCH_TASK_INFO, &task_thread_info(current)->l1_task_info,
152 sizeof(*L1_SCRATCH_TASK_INFO));
156 EXPORT_SYMBOL_GPL(start_thread);
158 void flush_thread(void)
162 asmlinkage int bfin_vfork(struct pt_regs *regs)
164 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0, NULL,
168 asmlinkage int bfin_clone(struct pt_regs *regs)
170 unsigned long clone_flags;
173 #ifdef __ARCH_SYNC_CORE_DCACHE
174 if (current->rt.nr_cpus_allowed == num_possible_cpus())
175 set_cpus_allowed_ptr(current, cpumask_of(smp_processor_id()));
178 /* syscall2 puts clone_flags in r0 and usp in r1 */
179 clone_flags = regs->r0;
185 return do_fork(clone_flags, newsp, regs, 0, NULL, NULL);
189 copy_thread(unsigned long clone_flags,
190 unsigned long usp, unsigned long topstk,
191 struct task_struct *p, struct pt_regs *regs)
193 struct pt_regs *childregs;
195 childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;
200 p->thread.ksp = (unsigned long)childregs;
201 p->thread.pc = (unsigned long)ret_from_fork;
207 * sys_execve() executes a new program.
209 asmlinkage int sys_execve(const char __user *name,
210 const char __user *const __user *argv,
211 const char __user *const __user *envp)
215 struct pt_regs *regs = (struct pt_regs *)((&name) + 6);
217 filename = getname(name);
218 error = PTR_ERR(filename);
219 if (IS_ERR(filename))
221 error = do_execve(filename, argv, envp, regs);
226 unsigned long get_wchan(struct task_struct *p)
228 unsigned long fp, pc;
229 unsigned long stack_page;
231 if (!p || p == current || p->state == TASK_RUNNING)
234 stack_page = (unsigned long)p;
237 if (fp < stack_page + sizeof(struct thread_info) ||
238 fp >= 8184 + stack_page)
240 pc = ((unsigned long *)fp)[1];
241 if (!in_sched_functions(pc))
243 fp = *(unsigned long *)fp;
245 while (count++ < 16);
249 void finish_atomic_sections (struct pt_regs *regs)
251 int __user *up0 = (int __user *)regs->p0;
255 /* not in middle of an atomic step, so resume like normal */
258 case ATOMIC_XCHG32 + 2:
259 put_user(regs->r1, up0);
262 case ATOMIC_CAS32 + 2:
263 case ATOMIC_CAS32 + 4:
264 if (regs->r0 == regs->r1)
265 case ATOMIC_CAS32 + 6:
266 put_user(regs->r2, up0);
269 case ATOMIC_ADD32 + 2:
270 regs->r0 = regs->r1 + regs->r0;
272 case ATOMIC_ADD32 + 4:
273 put_user(regs->r0, up0);
276 case ATOMIC_SUB32 + 2:
277 regs->r0 = regs->r1 - regs->r0;
279 case ATOMIC_SUB32 + 4:
280 put_user(regs->r0, up0);
283 case ATOMIC_IOR32 + 2:
284 regs->r0 = regs->r1 | regs->r0;
286 case ATOMIC_IOR32 + 4:
287 put_user(regs->r0, up0);
290 case ATOMIC_AND32 + 2:
291 regs->r0 = regs->r1 & regs->r0;
293 case ATOMIC_AND32 + 4:
294 put_user(regs->r0, up0);
297 case ATOMIC_XOR32 + 2:
298 regs->r0 = regs->r1 ^ regs->r0;
300 case ATOMIC_XOR32 + 4:
301 put_user(regs->r0, up0);
306 * We've finished the atomic section, and the only thing left for
307 * userspace is to do a RTS, so we might as well handle that too
308 * since we need to update the PC anyways.
310 regs->pc = regs->rets;
314 int in_mem(unsigned long addr, unsigned long size,
315 unsigned long start, unsigned long end)
317 return addr >= start && addr + size <= end;
320 int in_mem_const_off(unsigned long addr, unsigned long size, unsigned long off,
321 unsigned long const_addr, unsigned long const_size)
324 in_mem(addr, size, const_addr + off, const_addr + const_size);
327 int in_mem_const(unsigned long addr, unsigned long size,
328 unsigned long const_addr, unsigned long const_size)
330 return in_mem_const_off(addr, size, 0, const_addr, const_size);
332 #define ASYNC_ENABLED(bnum, bctlnum) \
334 (bfin_read_EBIU_AMGCTL() & 0xe) < ((bnum + 1) << 1) ? 0 : \
335 bfin_read_EBIU_AMBCTL##bctlnum() & B##bnum##RDYEN ? 0 : \
339 * We can't read EBIU banks that aren't enabled or we end up hanging
340 * on the access to the async space. Make sure we validate accesses
341 * that cross async banks too.
342 * 0 - found, but unusable
347 int in_async(unsigned long addr, unsigned long size)
349 if (addr >= ASYNC_BANK0_BASE && addr < ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE) {
350 if (!ASYNC_ENABLED(0, 0))
352 if (addr + size <= ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE)
354 size -= ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE - addr;
355 addr = ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE;
357 if (addr >= ASYNC_BANK1_BASE && addr < ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE) {
358 if (!ASYNC_ENABLED(1, 0))
360 if (addr + size <= ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE)
362 size -= ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE - addr;
363 addr = ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE;
365 if (addr >= ASYNC_BANK2_BASE && addr < ASYNC_BANK2_BASE + ASYNC_BANK2_SIZE) {
366 if (!ASYNC_ENABLED(2, 1))
368 if (addr + size <= ASYNC_BANK2_BASE + ASYNC_BANK2_SIZE)
370 size -= ASYNC_BANK2_BASE + ASYNC_BANK2_SIZE - addr;
371 addr = ASYNC_BANK2_BASE + ASYNC_BANK2_SIZE;
373 if (addr >= ASYNC_BANK3_BASE && addr < ASYNC_BANK3_BASE + ASYNC_BANK3_SIZE) {
374 if (ASYNC_ENABLED(3, 1))
376 if (addr + size <= ASYNC_BANK3_BASE + ASYNC_BANK3_SIZE)
381 /* not within async bounds */
385 int bfin_mem_access_type(unsigned long addr, unsigned long size)
387 int cpu = raw_smp_processor_id();
389 /* Check that things do not wrap around */
390 if (addr > ULONG_MAX - size)
393 if (in_mem(addr, size, FIXED_CODE_START, physical_mem_end))
394 return BFIN_MEM_ACCESS_CORE;
396 if (in_mem_const(addr, size, L1_CODE_START, L1_CODE_LENGTH))
397 return cpu == 0 ? BFIN_MEM_ACCESS_ITEST : BFIN_MEM_ACCESS_IDMA;
398 if (in_mem_const(addr, size, L1_SCRATCH_START, L1_SCRATCH_LENGTH))
399 return cpu == 0 ? BFIN_MEM_ACCESS_CORE_ONLY : -EFAULT;
400 if (in_mem_const(addr, size, L1_DATA_A_START, L1_DATA_A_LENGTH))
401 return cpu == 0 ? BFIN_MEM_ACCESS_CORE : BFIN_MEM_ACCESS_IDMA;
402 if (in_mem_const(addr, size, L1_DATA_B_START, L1_DATA_B_LENGTH))
403 return cpu == 0 ? BFIN_MEM_ACCESS_CORE : BFIN_MEM_ACCESS_IDMA;
404 #ifdef COREB_L1_CODE_START
405 if (in_mem_const(addr, size, COREB_L1_CODE_START, COREB_L1_CODE_LENGTH))
406 return cpu == 1 ? BFIN_MEM_ACCESS_ITEST : BFIN_MEM_ACCESS_IDMA;
407 if (in_mem_const(addr, size, COREB_L1_SCRATCH_START, L1_SCRATCH_LENGTH))
408 return cpu == 1 ? BFIN_MEM_ACCESS_CORE_ONLY : -EFAULT;
409 if (in_mem_const(addr, size, COREB_L1_DATA_A_START, COREB_L1_DATA_A_LENGTH))
410 return cpu == 1 ? BFIN_MEM_ACCESS_CORE : BFIN_MEM_ACCESS_IDMA;
411 if (in_mem_const(addr, size, COREB_L1_DATA_B_START, COREB_L1_DATA_B_LENGTH))
412 return cpu == 1 ? BFIN_MEM_ACCESS_CORE : BFIN_MEM_ACCESS_IDMA;
414 if (in_mem_const(addr, size, L2_START, L2_LENGTH))
415 return BFIN_MEM_ACCESS_CORE;
417 if (addr >= SYSMMR_BASE)
418 return BFIN_MEM_ACCESS_CORE_ONLY;
420 switch (in_async(addr, size)) {
421 case 0: return -EFAULT;
422 case 1: return BFIN_MEM_ACCESS_CORE;
423 case 2: /* fall through */;
426 if (in_mem_const(addr, size, BOOT_ROM_START, BOOT_ROM_LENGTH))
427 return BFIN_MEM_ACCESS_CORE;
428 if (in_mem_const(addr, size, L1_ROM_START, L1_ROM_LENGTH))
429 return BFIN_MEM_ACCESS_DMA;
434 #if defined(CONFIG_ACCESS_CHECK)
435 #ifdef CONFIG_ACCESS_OK_L1
436 __attribute__((l1_text))
438 /* Return 1 if access to memory range is OK, 0 otherwise */
439 int _access_ok(unsigned long addr, unsigned long size)
445 /* Check that things do not wrap around */
446 if (addr > ULONG_MAX - size)
448 if (segment_eq(get_fs(), KERNEL_DS))
450 #ifdef CONFIG_MTD_UCLINUX
456 if (in_mem(addr, size, memory_start, memory_end))
458 if (in_mem(addr, size, memory_mtd_end, physical_mem_end))
460 # ifndef CONFIG_ROMFS_ON_MTD
463 /* For XIP, allow user space to use pointers within the ROMFS. */
464 if (in_mem(addr, size, memory_mtd_start, memory_mtd_end))
467 if (in_mem(addr, size, memory_start, physical_mem_end))
471 if (in_mem(addr, size, (unsigned long)__init_begin, (unsigned long)__init_end))
474 if (in_mem_const(addr, size, L1_CODE_START, L1_CODE_LENGTH))
476 if (in_mem_const_off(addr, size, _etext_l1 - _stext_l1, L1_CODE_START, L1_CODE_LENGTH))
478 if (in_mem_const_off(addr, size, _ebss_l1 - _sdata_l1, L1_DATA_A_START, L1_DATA_A_LENGTH))
480 if (in_mem_const_off(addr, size, _ebss_b_l1 - _sdata_b_l1, L1_DATA_B_START, L1_DATA_B_LENGTH))
482 #ifdef COREB_L1_CODE_START
483 if (in_mem_const(addr, size, COREB_L1_CODE_START, COREB_L1_CODE_LENGTH))
485 if (in_mem_const(addr, size, COREB_L1_SCRATCH_START, L1_SCRATCH_LENGTH))
487 if (in_mem_const(addr, size, COREB_L1_DATA_A_START, COREB_L1_DATA_A_LENGTH))
489 if (in_mem_const(addr, size, COREB_L1_DATA_B_START, COREB_L1_DATA_B_LENGTH))
493 #ifndef CONFIG_EXCEPTION_L1_SCRATCH
494 if (in_mem_const(addr, size, (unsigned long)l1_stack_base, l1_stack_len))
498 aret = in_async(addr, size);
502 if (in_mem_const_off(addr, size, _ebss_l2 - _stext_l2, L2_START, L2_LENGTH))
505 if (in_mem_const(addr, size, BOOT_ROM_START, BOOT_ROM_LENGTH))
507 if (in_mem_const(addr, size, L1_ROM_START, L1_ROM_LENGTH))
512 EXPORT_SYMBOL(_access_ok);
513 #endif /* CONFIG_ACCESS_CHECK */