xref: /linux/arch/mips/include/asm/irqflags.h (revision b889fcf63cb62e7fdb7816565e28f44dbe4a76a5)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1994, 95, 96, 97, 98, 99, 2003 by Ralf Baechle
7  * Copyright (C) 1996 by Paul M. Antoine
8  * Copyright (C) 1999 Silicon Graphics
9  * Copyright (C) 2000 MIPS Technologies, Inc.
10  */
11 #ifndef _ASM_IRQFLAGS_H
12 #define _ASM_IRQFLAGS_H
13 
14 #ifndef __ASSEMBLY__
15 
16 #include <linux/compiler.h>
17 #include <asm/hazards.h>
18 
19 #if defined(CONFIG_CPU_MIPSR2) && !defined(CONFIG_MIPS_MT_SMTC)
20 
21 __asm__(
22 	"	.macro	arch_local_irq_disable\n"
23 	"	.set	push						\n"
24 	"	.set	noat						\n"
25 	"	di							\n"
26 	"	irq_disable_hazard					\n"
27 	"	.set	pop						\n"
28 	"	.endm							\n");
29 
30 static inline void arch_local_irq_disable(void)
31 {
32 	__asm__ __volatile__(
33 		"arch_local_irq_disable"
34 		: /* no outputs */
35 		: /* no inputs */
36 		: "memory");
37 }
38 
39 
40 __asm__(
41 	"	.macro	arch_local_irq_save result			\n"
42 	"	.set	push						\n"
43 	"	.set	reorder						\n"
44 	"	.set	noat						\n"
45 	"	di	\\result					\n"
46 	"	andi	\\result, 1					\n"
47 	"	irq_disable_hazard					\n"
48 	"	.set	pop						\n"
49 	"	.endm							\n");
50 
51 static inline unsigned long arch_local_irq_save(void)
52 {
53 	unsigned long flags;
54 	asm volatile("arch_local_irq_save\t%0"
55 		     : "=r" (flags)
56 		     : /* no inputs */
57 		     : "memory");
58 	return flags;
59 }
60 
61 
62 __asm__(
63 	"	.macro	arch_local_irq_restore flags			\n"
64 	"	.set	push						\n"
65 	"	.set	noreorder					\n"
66 	"	.set	noat						\n"
67 #if defined(CONFIG_IRQ_CPU)
68 	/*
69 	 * Slow, but doesn't suffer from a relatively unlikely race
70 	 * condition we're having since days 1.
71 	 */
72 	"	beqz	\\flags, 1f					\n"
73 	"	di							\n"
74 	"	ei							\n"
75 	"1:								\n"
76 #else
77 	/*
78 	 * Fast, dangerous.  Life is fun, life is good.
79 	 */
80 	"	mfc0	$1, $12						\n"
81 	"	ins	$1, \\flags, 0, 1				\n"
82 	"	mtc0	$1, $12						\n"
83 #endif
84 	"	irq_disable_hazard					\n"
85 	"	.set	pop						\n"
86 	"	.endm							\n");
87 
88 static inline void arch_local_irq_restore(unsigned long flags)
89 {
90 	unsigned long __tmp1;
91 
92 	__asm__ __volatile__(
93 		"arch_local_irq_restore\t%0"
94 		: "=r" (__tmp1)
95 		: "0" (flags)
96 		: "memory");
97 }
98 
99 static inline void __arch_local_irq_restore(unsigned long flags)
100 {
101 	unsigned long __tmp1;
102 
103 	__asm__ __volatile__(
104 		"arch_local_irq_restore\t%0"
105 		: "=r" (__tmp1)
106 		: "0" (flags)
107 		: "memory");
108 }
109 #else
110 /* Functions that require preempt_{dis,en}able() are in mips-atomic.c */
111 void arch_local_irq_disable(void);
112 unsigned long arch_local_irq_save(void);
113 void arch_local_irq_restore(unsigned long flags);
114 void __arch_local_irq_restore(unsigned long flags);
115 #endif /* if defined(CONFIG_CPU_MIPSR2) && !defined(CONFIG_MIPS_MT_SMTC) */
116 
117 
118 __asm__(
119 	"	.macro	arch_local_irq_enable				\n"
120 	"	.set	push						\n"
121 	"	.set	reorder						\n"
122 	"	.set	noat						\n"
123 #ifdef CONFIG_MIPS_MT_SMTC
124 	"	mfc0	$1, $2, 1	# SMTC - clear TCStatus.IXMT	\n"
125 	"	ori	$1, 0x400					\n"
126 	"	xori	$1, 0x400					\n"
127 	"	mtc0	$1, $2, 1					\n"
128 #elif defined(CONFIG_CPU_MIPSR2)
129 	"	ei							\n"
130 #else
131 	"	mfc0	$1,$12						\n"
132 	"	ori	$1,0x1f						\n"
133 	"	xori	$1,0x1e						\n"
134 	"	mtc0	$1,$12						\n"
135 #endif
136 	"	irq_enable_hazard					\n"
137 	"	.set	pop						\n"
138 	"	.endm");
139 
140 extern void smtc_ipi_replay(void);
141 
142 static inline void arch_local_irq_enable(void)
143 {
144 #ifdef CONFIG_MIPS_MT_SMTC
145 	/*
146 	 * SMTC kernel needs to do a software replay of queued
147 	 * IPIs, at the cost of call overhead on each local_irq_enable()
148 	 */
149 	smtc_ipi_replay();
150 #endif
151 	__asm__ __volatile__(
152 		"arch_local_irq_enable"
153 		: /* no outputs */
154 		: /* no inputs */
155 		: "memory");
156 }
157 
158 
159 __asm__(
160 	"	.macro	arch_local_save_flags flags			\n"
161 	"	.set	push						\n"
162 	"	.set	reorder						\n"
163 #ifdef CONFIG_MIPS_MT_SMTC
164 	"	mfc0	\\flags, $2, 1					\n"
165 #else
166 	"	mfc0	\\flags, $12					\n"
167 #endif
168 	"	.set	pop						\n"
169 	"	.endm							\n");
170 
171 static inline unsigned long arch_local_save_flags(void)
172 {
173 	unsigned long flags;
174 	asm volatile("arch_local_save_flags %0" : "=r" (flags));
175 	return flags;
176 }
177 
178 
179 static inline int arch_irqs_disabled_flags(unsigned long flags)
180 {
181 #ifdef CONFIG_MIPS_MT_SMTC
182 	/*
183 	 * SMTC model uses TCStatus.IXMT to disable interrupts for a thread/CPU
184 	 */
185 	return flags & 0x400;
186 #else
187 	return !(flags & 1);
188 #endif
189 }
190 
191 #endif /* #ifndef __ASSEMBLY__ */
192 
193 /*
194  * Do the CPU's IRQ-state tracing from assembly code.
195  */
196 #ifdef CONFIG_TRACE_IRQFLAGS
197 /* Reload some registers clobbered by trace_hardirqs_on */
198 #ifdef CONFIG_64BIT
199 # define TRACE_IRQS_RELOAD_REGS						\
200 	LONG_L	$11, PT_R11(sp);					\
201 	LONG_L	$10, PT_R10(sp);					\
202 	LONG_L	$9, PT_R9(sp);						\
203 	LONG_L	$8, PT_R8(sp);						\
204 	LONG_L	$7, PT_R7(sp);						\
205 	LONG_L	$6, PT_R6(sp);						\
206 	LONG_L	$5, PT_R5(sp);						\
207 	LONG_L	$4, PT_R4(sp);						\
208 	LONG_L	$2, PT_R2(sp)
209 #else
210 # define TRACE_IRQS_RELOAD_REGS						\
211 	LONG_L	$7, PT_R7(sp);						\
212 	LONG_L	$6, PT_R6(sp);						\
213 	LONG_L	$5, PT_R5(sp);						\
214 	LONG_L	$4, PT_R4(sp);						\
215 	LONG_L	$2, PT_R2(sp)
216 #endif
217 # define TRACE_IRQS_ON							\
218 	CLI;	/* make sure trace_hardirqs_on() is called in kernel level */ \
219 	jal	trace_hardirqs_on
220 # define TRACE_IRQS_ON_RELOAD						\
221 	TRACE_IRQS_ON;							\
222 	TRACE_IRQS_RELOAD_REGS
223 # define TRACE_IRQS_OFF							\
224 	jal	trace_hardirqs_off
225 #else
226 # define TRACE_IRQS_ON
227 # define TRACE_IRQS_ON_RELOAD
228 # define TRACE_IRQS_OFF
229 #endif
230 
231 #endif /* _ASM_IRQFLAGS_H */
232