xref: /linux/arch/arc/include/asm/irqflags-compact.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
3  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  */
9 
10 #ifndef __ASM_IRQFLAGS_ARCOMPACT_H
11 #define __ASM_IRQFLAGS_ARCOMPACT_H
12 
13 /* vineetg: March 2010 : local_irq_save( ) optimisation
14  *  -Remove explicit mov of current status32 into reg, that is not needed
15  *  -Use BIC  insn instead of INVERTED + AND
16  *  -Conditionally disable interrupts (if they are not enabled, don't disable)
17 */
18 
19 #include <asm/arcregs.h>
20 
21 /* status32 Reg bits related to Interrupt Handling */
22 #define STATUS_E1_BIT		1	/* Int 1 enable */
23 #define STATUS_E2_BIT		2	/* Int 2 enable */
24 #define STATUS_A1_BIT		3	/* Int 1 active */
25 #define STATUS_A2_BIT		4	/* Int 2 active */
26 
27 #define STATUS_E1_MASK		(1<<STATUS_E1_BIT)
28 #define STATUS_E2_MASK		(1<<STATUS_E2_BIT)
29 #define STATUS_A1_MASK		(1<<STATUS_A1_BIT)
30 #define STATUS_A2_MASK		(1<<STATUS_A2_BIT)
31 #define STATUS_IE_MASK		(STATUS_E1_MASK | STATUS_E2_MASK)
32 
33 /* Other Interrupt Handling related Aux regs */
34 #define AUX_IRQ_LEV		0x200	/* IRQ Priority: L1 or L2 */
35 #define AUX_IRQ_HINT		0x201	/* For generating Soft Interrupts */
36 #define AUX_IRQ_LV12		0x43	/* interrupt level register */
37 
38 #define AUX_IENABLE		0x40c
39 #define AUX_ITRIGGER		0x40d
40 #define AUX_IPULSE		0x415
41 
42 #define ISA_INIT_STATUS_BITS	STATUS_IE_MASK
43 
44 #ifndef __ASSEMBLY__
45 
46 /******************************************************************
47  * IRQ Control Macros
48  *
49  * All of them have "memory" clobber (compiler barrier) which is needed to
50  * ensure that LD/ST requiring irq safetly (R-M-W when LLSC is not available)
51  * are redone after IRQs are re-enabled (and gcc doesn't reuse stale register)
52  *
53  * Noted at the time of Abilis Timer List corruption
54  *	Orig Bug + Rejected solution	: https://lkml.org/lkml/2013/3/29/67
55  *	Reasoning			: https://lkml.org/lkml/2013/4/8/15
56  *
57  ******************************************************************/
58 
59 /*
60  * Save IRQ state and disable IRQs
61  */
62 static inline long arch_local_irq_save(void)
63 {
64 	unsigned long temp, flags;
65 
66 	__asm__ __volatile__(
67 	"	lr  %1, [status32]	\n"
68 	"	bic %0, %1, %2		\n"
69 	"	and.f 0, %1, %2	\n"
70 	"	flag.nz %0		\n"
71 	: "=r"(temp), "=r"(flags)
72 	: "n"((STATUS_E1_MASK | STATUS_E2_MASK))
73 	: "memory", "cc");
74 
75 	return flags;
76 }
77 
78 /*
79  * restore saved IRQ state
80  */
81 static inline void arch_local_irq_restore(unsigned long flags)
82 {
83 
84 	__asm__ __volatile__(
85 	"	flag %0			\n"
86 	:
87 	: "r"(flags)
88 	: "memory");
89 }
90 
91 /*
92  * Unconditionally Enable IRQs
93  */
94 extern void arch_local_irq_enable(void);
95 
96 /*
97  * Unconditionally Disable IRQs
98  */
99 static inline void arch_local_irq_disable(void)
100 {
101 	unsigned long temp;
102 
103 	__asm__ __volatile__(
104 	"	lr  %0, [status32]	\n"
105 	"	and %0, %0, %1		\n"
106 	"	flag %0			\n"
107 	: "=&r"(temp)
108 	: "n"(~(STATUS_E1_MASK | STATUS_E2_MASK))
109 	: "memory");
110 }
111 
112 /*
113  * save IRQ state
114  */
115 static inline long arch_local_save_flags(void)
116 {
117 	unsigned long temp;
118 
119 	__asm__ __volatile__(
120 	"	lr  %0, [status32]	\n"
121 	: "=&r"(temp)
122 	:
123 	: "memory");
124 
125 	return temp;
126 }
127 
128 /*
129  * Query IRQ state
130  */
131 static inline int arch_irqs_disabled_flags(unsigned long flags)
132 {
133 	return !(flags & (STATUS_E1_MASK
134 #ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
135 			| STATUS_E2_MASK
136 #endif
137 		));
138 }
139 
140 static inline int arch_irqs_disabled(void)
141 {
142 	return arch_irqs_disabled_flags(arch_local_save_flags());
143 }
144 
145 #else
146 
147 #ifdef CONFIG_TRACE_IRQFLAGS
148 
149 .macro TRACE_ASM_IRQ_DISABLE
150 	bl	trace_hardirqs_off
151 .endm
152 
153 .macro TRACE_ASM_IRQ_ENABLE
154 	bl	trace_hardirqs_on
155 .endm
156 
157 #else
158 
159 .macro TRACE_ASM_IRQ_DISABLE
160 .endm
161 
162 .macro TRACE_ASM_IRQ_ENABLE
163 .endm
164 
165 #endif
166 
167 .macro IRQ_DISABLE  scratch
168 	lr	\scratch, [status32]
169 	bic	\scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)
170 	flag	\scratch
171 	TRACE_ASM_IRQ_DISABLE
172 .endm
173 
174 .macro IRQ_ENABLE  scratch
175 	lr	\scratch, [status32]
176 	or	\scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)
177 	flag	\scratch
178 	TRACE_ASM_IRQ_ENABLE
179 .endm
180 
181 #endif	/* __ASSEMBLY__ */
182 
183 #endif
184