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author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/sh/kernel/cpu/fpu.c |
Initial import
Diffstat (limited to 'arch/sh/kernel/cpu/fpu.c')
-rw-r--r-- | arch/sh/kernel/cpu/fpu.c | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/arch/sh/kernel/cpu/fpu.c b/arch/sh/kernel/cpu/fpu.c new file mode 100644 index 000000000..4e332244e --- /dev/null +++ b/arch/sh/kernel/cpu/fpu.c @@ -0,0 +1,86 @@ +#include <linux/sched.h> +#include <linux/slab.h> +#include <asm/processor.h> +#include <asm/fpu.h> +#include <asm/traps.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->thread.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 */ |