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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/blackfin/kernel/process.c
Initial import
Diffstat (limited to 'arch/blackfin/kernel/process.c')
-rw-r--r--arch/blackfin/kernel/process.c434
1 files changed, 434 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/process.c b/arch/blackfin/kernel/process.c
new file mode 100644
index 000000000..4aa5545c4
--- /dev/null
+++ b/arch/blackfin/kernel/process.c
@@ -0,0 +1,434 @@
+/*
+ * 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/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 (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
+
+#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 */