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-rw-r--r--arch/sh/kernel/process_32.c197
1 files changed, 197 insertions, 0 deletions
diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c
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index 000000000..92b6649d4
--- /dev/null
+++ b/arch/sh/kernel/process_32.c
@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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
+ */
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task.h>
+#include <linux/sched/task_stack.h>
+#include <linux/slab.h>
+#include <linux/elfcore.h>
+#include <linux/fs.h>
+#include <linux/ftrace.h>
+#include <linux/hw_breakpoint.h>
+#include <linux/prefetch.h>
+#include <linux/stackprotector.h>
+#include <linux/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)
+{
+ pr_info("\n");
+ show_regs_print_info(KERN_DEFAULT);
+
+ pr_info("PC is at %pS\n", (void *)instruction_pointer(regs));
+ pr_info("PR is at %pS\n", (void *)regs->pr);
+
+ pr_info("PC : %08lx SP : %08lx SR : %08lx ", regs->pc,
+ regs->regs[15], regs->sr);
+#ifdef CONFIG_MMU
+ pr_cont("TEA : %08x\n", __raw_readl(MMU_TEA));
+#else
+ pr_cont("\n");
+#endif
+
+ pr_info("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n",
+ regs->regs[0], regs->regs[1], regs->regs[2], regs->regs[3]);
+ pr_info("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n",
+ regs->regs[4], regs->regs[5], regs->regs[6], regs->regs[7]);
+ pr_info("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n",
+ regs->regs[8], regs->regs[9], regs->regs[10], regs->regs[11]);
+ pr_info("R12 : %08lx R13 : %08lx R14 : %08lx\n",
+ regs->regs[12], regs->regs[13], regs->regs[14]);
+ pr_info("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, KERN_DEFAULT);
+ show_code(regs);
+}
+
+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);
+
+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
+}
+
+asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
+
+int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
+{
+ unsigned long clone_flags = args->flags;
+ unsigned long usp = args->stack;
+ unsigned long tls = args->tls;
+ 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
+
+ memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
+
+ childregs = task_pt_regs(p);
+ p->thread.sp = (unsigned long) childregs;
+ if (unlikely(args->fn)) {
+ memset(childregs, 0, sizeof(struct pt_regs));
+ p->thread.pc = (unsigned long) ret_from_kernel_thread;
+ childregs->regs[4] = (unsigned long) args->fn_arg;
+ childregs->regs[5] = (unsigned long) args->fn;
+ childregs->sr = SR_MD;
+#if defined(CONFIG_SH_FPU)
+ childregs->sr |= SR_FD;
+#endif
+ ti->status &= ~TS_USEDFPU;
+ p->thread.fpu_counter = 0;
+ return 0;
+ }
+ *childregs = *current_pt_regs();
+
+ if (usp)
+ childregs->regs[15] = usp;
+
+ if (clone_flags & CLONE_SETTLS)
+ childregs->gbr = tls;
+
+ childregs->regs[0] = 0; /* Set return value for child */
+ p->thread.pc = (unsigned long) ret_from_fork;
+ 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;
+
+#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP)
+ __stack_chk_guard = next->stack_canary;
+#endif
+
+ unlazy_fpu(prev, task_pt_regs(prev));
+
+ /* we're going to use this soon, after a few expensive things */
+ if (next->thread.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->thread.fpu_counter > 5)
+ __fpu_state_restore();
+
+ return prev;
+}
+
+unsigned long __get_wchan(struct task_struct *p)
+{
+ unsigned long pc;
+
+ /*
+ * 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;
+}