1 files changed, 84 insertions, 0 deletions

diff --git a/arch/sh/kernel/cpu/fpu.c b/arch/sh/kernel/cpu/fpu.c
new file mode 100644
index 000000000000..f059ed62cf57
--- /dev/null
+++ b/arch/sh/kernel/cpu/fpu.c
@@ -0,0 +1,84 @@
+#include <linux/sched.h>
+#include <asm/processor.h>
+#include <asm/fpu.h>
+
+int init_fpu(struct task_struct *tsk)
+{
+        if (tsk_used_math(tsk)) {
+                if ((boot_cpu_data.flags & CPU_HAS_FPU) && tsk == current)
+                        unlazy_fpu(tsk, task_pt_regs(tsk));
+                return 0;
+        }
+
+        /*
+         * Memory allocation at the first usage of the FPU and other state.
+         */
+        if (!tsk->thread.xstate) {
+                tsk->thread.xstate = kmem_cache_alloc(task_xstate_cachep,
+                                                      GFP_KERNEL);
+                if (!tsk->thread.xstate)
+                        return -ENOMEM;
+        }
+
+        if (boot_cpu_data.flags & CPU_HAS_FPU) {
+                struct sh_fpu_hard_struct *fp = &tsk->thread.xstate->hardfpu;
+                memset(fp, 0, xstate_size);
+                fp->fpscr = FPSCR_INIT;
+        } else {
+                struct sh_fpu_soft_struct *fp = &tsk->thread.xstate->softfpu;
+                memset(fp, 0, xstate_size);
+                fp->fpscr = FPSCR_INIT;
+        }
+
+        set_stopped_child_used_math(tsk);
+        return 0;
+}
+
+#ifdef CONFIG_SH_FPU
+void __fpu_state_restore(void)
+{
+        struct task_struct *tsk = current;
+
+        restore_fpu(tsk);
+
+        task_thread_info(tsk)->status |= TS_USEDFPU;
+        tsk->fpu_counter++;
+}
+
+void fpu_state_restore(struct pt_regs *regs)
+{
+        struct task_struct *tsk = current;
+
+        if (unlikely(!user_mode(regs))) {
+                printk(KERN_ERR "BUG: FPU is used in kernel mode.\n");
+                BUG();
+                return;
+        }
+
+        if (!tsk_used_math(tsk)) {
+                local_irq_enable();
+                /*
+                 * does a slab alloc which can sleep
+                 */
+                if (init_fpu(tsk)) {
+                        /*
+                         * ran out of memory!
+                         */
+                        do_group_exit(SIGKILL);
+                        return;
+                }
+                local_irq_disable();
+        }
+
+        grab_fpu(regs);
+
+        __fpu_state_restore();
+}
+
+BUILD_TRAP_HANDLER(fpu_state_restore)
+{
+        TRAP_HANDLER_DECL;
+
+        fpu_state_restore(regs);
+}
+#endif /* CONFIG_SH_FPU */