Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) #include <linux/sched/signal.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3) #include <linux/sched/task.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4) #include <linux/sched/task_stack.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) #include <asm/processor.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) #include <asm/fpu.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <asm/traps.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <asm/ptrace.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) int init_fpu(struct task_struct *tsk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) 	if (tsk_used_math(tsk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 		if ((boot_cpu_data.flags & CPU_HAS_FPU) && tsk == current)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 			unlazy_fpu(tsk, task_pt_regs(tsk));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 	 * Memory allocation at the first usage of the FPU and other state.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 	if (!tsk->thread.xstate) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 		tsk->thread.xstate = kmem_cache_alloc(task_xstate_cachep,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 						      GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 		if (!tsk->thread.xstate)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 			return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 	if (boot_cpu_data.flags & CPU_HAS_FPU) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 		struct sh_fpu_hard_struct *fp = &tsk->thread.xstate->hardfpu;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 		memset(fp, 0, xstate_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 		fp->fpscr = FPSCR_INIT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 		struct sh_fpu_soft_struct *fp = &tsk->thread.xstate->softfpu;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 		memset(fp, 0, xstate_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 		fp->fpscr = FPSCR_INIT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	set_stopped_child_used_math(tsk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) #ifdef CONFIG_SH_FPU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) void __fpu_state_restore(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	struct task_struct *tsk = current;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	restore_fpu(tsk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 	task_thread_info(tsk)->status |= TS_USEDFPU;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	tsk->thread.fpu_counter++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) void fpu_state_restore(struct pt_regs *regs)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 	struct task_struct *tsk = current;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 	if (unlikely(!user_mode(regs))) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 		printk(KERN_ERR "BUG: FPU is used in kernel mode.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 		BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 	if (!tsk_used_math(tsk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 		int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 		/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 		 * does a slab alloc which can sleep
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 		 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 		local_irq_enable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 		ret = init_fpu(tsk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 		local_irq_disable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 		if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 			/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 			 * ran out of memory!
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) 			 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 			force_sig(SIGKILL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) 			return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) 	grab_fpu(regs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) 	__fpu_state_restore();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) BUILD_TRAP_HANDLER(fpu_state_restore)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) 	TRAP_HANDLER_DECL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) 	fpu_state_restore(regs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) #endif /* CONFIG_SH_FPU */