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-rw-r--r--arch/sh/kernel/process_32.c338
1 files changed, 338 insertions, 0 deletions
diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c
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--- /dev/null
+++ b/arch/sh/kernel/process_32.c
@@ -0,0 +1,338 @@
+/*
+ * arch/sh/kernel/process.c
+ *
+ * This file handles the architecture-dependent parts of process handling..
+ *
+ * Copyright (C) 1995 Linus Torvalds
+ *
+ * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
+ * Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC
+ * Copyright (C) 2002 - 2008 Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/elfcore.h>
+#include <linux/kallsyms.h>
+#include <linux/fs.h>
+#include <linux/ftrace.h>
+#include <linux/hw_breakpoint.h>
+#include <linux/prefetch.h>
+#include <asm/uaccess.h>
+#include <asm/mmu_context.h>
+#include <asm/fpu.h>
+#include <asm/syscalls.h>
+#include <asm/switch_to.h>
+
+void show_regs(struct pt_regs * regs)
+{
+ printk("\n");
+ printk("Pid : %d, Comm: \t\t%s\n", task_pid_nr(current), current->comm);
+ printk("CPU : %d \t\t%s (%s %.*s)\n\n",
+ smp_processor_id(), print_tainted(), init_utsname()->release,
+ (int)strcspn(init_utsname()->version, " "),
+ init_utsname()->version);
+
+ print_symbol("PC is at %s\n", instruction_pointer(regs));
+ print_symbol("PR is at %s\n", regs->pr);
+
+ printk("PC : %08lx SP : %08lx SR : %08lx ",
+ regs->pc, regs->regs[15], regs->sr);
+#ifdef CONFIG_MMU
+ printk("TEA : %08x\n", __raw_readl(MMU_TEA));
+#else
+ printk("\n");
+#endif
+
+ printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n",
+ regs->regs[0],regs->regs[1],
+ regs->regs[2],regs->regs[3]);
+ printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n",
+ regs->regs[4],regs->regs[5],
+ regs->regs[6],regs->regs[7]);
+ printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n",
+ regs->regs[8],regs->regs[9],
+ regs->regs[10],regs->regs[11]);
+ printk("R12 : %08lx R13 : %08lx R14 : %08lx\n",
+ regs->regs[12],regs->regs[13],
+ regs->regs[14]);
+ printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n",
+ regs->mach, regs->macl, regs->gbr, regs->pr);
+
+ show_trace(NULL, (unsigned long *)regs->regs[15], regs);
+ show_code(regs);
+}
+
+/*
+ * Create a kernel thread
+ */
+__noreturn void kernel_thread_helper(void *arg, int (*fn)(void *))
+{
+ do_exit(fn(arg));
+}
+
+/* Don't use this in BL=1(cli). Or else, CPU resets! */
+int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
+{
+ struct pt_regs regs;
+ int pid;
+
+ memset(&regs, 0, sizeof(regs));
+ regs.regs[4] = (unsigned long)arg;
+ regs.regs[5] = (unsigned long)fn;
+
+ regs.pc = (unsigned long)kernel_thread_helper;
+ regs.sr = SR_MD;
+#if defined(CONFIG_SH_FPU)
+ regs.sr |= SR_FD;
+#endif
+
+ /* Ok, create the new process.. */
+ pid = do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
+ &regs, 0, NULL, NULL);
+
+ return pid;
+}
+EXPORT_SYMBOL(kernel_thread);
+
+void start_thread(struct pt_regs *regs, unsigned long new_pc,
+ unsigned long new_sp)
+{
+ regs->pr = 0;
+ regs->sr = SR_FD;
+ regs->pc = new_pc;
+ regs->regs[15] = new_sp;
+
+ free_thread_xstate(current);
+}
+EXPORT_SYMBOL(start_thread);
+
+/*
+ * Free current thread data structures etc..
+ */
+void exit_thread(void)
+{
+}
+
+void flush_thread(void)
+{
+ struct task_struct *tsk = current;
+
+ flush_ptrace_hw_breakpoint(tsk);
+
+#if defined(CONFIG_SH_FPU)
+ /* Forget lazy FPU state */
+ clear_fpu(tsk, task_pt_regs(tsk));
+ clear_used_math();
+#endif
+}
+
+void release_thread(struct task_struct *dead_task)
+{
+ /* do nothing */
+}
+
+/* Fill in the fpu structure for a core dump.. */
+int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
+{
+ int fpvalid = 0;
+
+#if defined(CONFIG_SH_FPU)
+ struct task_struct *tsk = current;
+
+ fpvalid = !!tsk_used_math(tsk);
+ if (fpvalid)
+ fpvalid = !fpregs_get(tsk, NULL, 0,
+ sizeof(struct user_fpu_struct),
+ fpu, NULL);
+#endif
+
+ return fpvalid;
+}
+EXPORT_SYMBOL(dump_fpu);
+
+/*
+ * This gets called before we allocate a new thread and copy
+ * the current task into it.
+ */
+void prepare_to_copy(struct task_struct *tsk)
+{
+ unlazy_fpu(tsk, task_pt_regs(tsk));
+}
+
+asmlinkage void ret_from_fork(void);
+
+int copy_thread(unsigned long clone_flags, unsigned long usp,
+ unsigned long unused,
+ struct task_struct *p, struct pt_regs *regs)
+{
+ struct thread_info *ti = task_thread_info(p);
+ struct pt_regs *childregs;
+
+#if defined(CONFIG_SH_DSP)
+ struct task_struct *tsk = current;
+
+ if (is_dsp_enabled(tsk)) {
+ /* We can use the __save_dsp or just copy the struct:
+ * __save_dsp(p);
+ * p->thread.dsp_status.status |= SR_DSP
+ */
+ p->thread.dsp_status = tsk->thread.dsp_status;
+ }
+#endif
+
+ childregs = task_pt_regs(p);
+ *childregs = *regs;
+
+ if (user_mode(regs)) {
+ childregs->regs[15] = usp;
+ ti->addr_limit = USER_DS;
+ } else {
+ childregs->regs[15] = (unsigned long)childregs;
+ ti->addr_limit = KERNEL_DS;
+ ti->status &= ~TS_USEDFPU;
+ p->fpu_counter = 0;
+ }
+
+ if (clone_flags & CLONE_SETTLS)
+ childregs->gbr = childregs->regs[0];
+
+ childregs->regs[0] = 0; /* Set return value for child */
+
+ p->thread.sp = (unsigned long) childregs;
+ p->thread.pc = (unsigned long) ret_from_fork;
+
+ memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
+
+ return 0;
+}
+
+/*
+ * switch_to(x,y) should switch tasks from x to y.
+ *
+ */
+__notrace_funcgraph struct task_struct *
+__switch_to(struct task_struct *prev, struct task_struct *next)
+{
+ struct thread_struct *next_t = &next->thread;
+
+ unlazy_fpu(prev, task_pt_regs(prev));
+
+ /* we're going to use this soon, after a few expensive things */
+ if (next->fpu_counter > 5)
+ prefetch(next_t->xstate);
+
+#ifdef CONFIG_MMU
+ /*
+ * Restore the kernel mode register
+ * k7 (r7_bank1)
+ */
+ asm volatile("ldc %0, r7_bank"
+ : /* no output */
+ : "r" (task_thread_info(next)));
+#endif
+
+ /*
+ * If the task has used fpu the last 5 timeslices, just do a full
+ * restore of the math state immediately to avoid the trap; the
+ * chances of needing FPU soon are obviously high now
+ */
+ if (next->fpu_counter > 5)
+ __fpu_state_restore();
+
+ return prev;
+}
+
+asmlinkage int sys_fork(unsigned long r4, unsigned long r5,
+ unsigned long r6, unsigned long r7,
+ struct pt_regs __regs)
+{
+#ifdef CONFIG_MMU
+ struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
+ return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL);
+#else
+ /* fork almost works, enough to trick you into looking elsewhere :-( */
+ return -EINVAL;
+#endif
+}
+
+asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
+ unsigned long parent_tidptr,
+ unsigned long child_tidptr,
+ struct pt_regs __regs)
+{
+ struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
+ if (!newsp)
+ newsp = regs->regs[15];
+ return do_fork(clone_flags, newsp, regs, 0,
+ (int __user *)parent_tidptr,
+ (int __user *)child_tidptr);
+}
+
+/*
+ * This is trivial, and on the face of it looks like it
+ * could equally well be done in user mode.
+ *
+ * Not so, for quite unobvious reasons - register pressure.
+ * In user mode vfork() cannot have a stack frame, and if
+ * done by calling the "clone()" system call directly, you
+ * do not have enough call-clobbered registers to hold all
+ * the information you need.
+ */
+asmlinkage int sys_vfork(unsigned long r4, unsigned long r5,
+ unsigned long r6, unsigned long r7,
+ struct pt_regs __regs)
+{
+ struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
+ return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->regs[15], regs,
+ 0, NULL, NULL);
+}
+
+/*
+ * sys_execve() executes a new program.
+ */
+asmlinkage int sys_execve(const char __user *ufilename,
+ const char __user *const __user *uargv,
+ const char __user *const __user *uenvp,
+ unsigned long r7, struct pt_regs __regs)
+{
+ struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
+ int error;
+ char *filename;
+
+ filename = getname(ufilename);
+ error = PTR_ERR(filename);
+ if (IS_ERR(filename))
+ goto out;
+
+ error = do_execve(filename, uargv, uenvp, regs);
+ putname(filename);
+out:
+ return error;
+}
+
+unsigned long get_wchan(struct task_struct *p)
+{
+ unsigned long pc;
+
+ if (!p || p == current || p->state == TASK_RUNNING)
+ return 0;
+
+ /*
+ * The same comment as on the Alpha applies here, too ...
+ */
+ pc = thread_saved_pc(p);
+
+#ifdef CONFIG_FRAME_POINTER
+ if (in_sched_functions(pc)) {
+ unsigned long schedule_frame = (unsigned long)p->thread.sp;
+ return ((unsigned long *)schedule_frame)[21];
+ }
+#endif
+
+ return pc;
+}
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