1 /* 2 * Copyright (C) 2017 ARM Ltd. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program. If not, see <http://www.gnu.org/licenses/>. 15 */ 16 #ifndef __ASM_DAIFFLAGS_H 17 #define __ASM_DAIFFLAGS_H 18 19 #include <linux/irqflags.h> 20 21 #define DAIF_PROCCTX 0 22 #define DAIF_PROCCTX_NOIRQ PSR_I_BIT 23 24 /* mask/save/unmask/restore all exceptions, including interrupts. */ 25 static inline void local_daif_mask(void) 26 { 27 asm volatile( 28 "msr daifset, #0xf // local_daif_mask\n" 29 : 30 : 31 : "memory"); 32 trace_hardirqs_off(); 33 } 34 35 static inline unsigned long local_daif_save(void) 36 { 37 unsigned long flags; 38 39 asm volatile( 40 "mrs %0, daif // local_daif_save\n" 41 : "=r" (flags) 42 : 43 : "memory"); 44 local_daif_mask(); 45 46 return flags; 47 } 48 49 static inline void local_daif_unmask(void) 50 { 51 trace_hardirqs_on(); 52 asm volatile( 53 "msr daifclr, #0xf // local_daif_unmask" 54 : 55 : 56 : "memory"); 57 } 58 59 static inline void local_daif_restore(unsigned long flags) 60 { 61 if (!arch_irqs_disabled_flags(flags)) 62 trace_hardirqs_on(); 63 asm volatile( 64 "msr daif, %0 // local_daif_restore" 65 : 66 : "r" (flags) 67 : "memory"); 68 if (arch_irqs_disabled_flags(flags)) 69 trace_hardirqs_off(); 70 } 71 72 #endif 73