xref: /linux/arch/arc/include/asm/irqflags-compact.h (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
4  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
5  */
6 
7 #ifndef __ASM_IRQFLAGS_ARCOMPACT_H
8 #define __ASM_IRQFLAGS_ARCOMPACT_H
9 
10 /* vineetg: March 2010 : local_irq_save( ) optimisation
11  *  -Remove explicit mov of current status32 into reg, that is not needed
12  *  -Use BIC  insn instead of INVERTED + AND
13  *  -Conditionally disable interrupts (if they are not enabled, don't disable)
14 */
15 
16 #include <asm/arcregs.h>
17 
18 /* status32 Reg bits related to Interrupt Handling */
19 #define STATUS_E1_BIT		1	/* Int 1 enable */
20 #define STATUS_E2_BIT		2	/* Int 2 enable */
21 #define STATUS_A1_BIT		3	/* Int 1 active */
22 #define STATUS_A2_BIT		4	/* Int 2 active */
23 #define STATUS_AE_BIT		5	/* Exception active */
24 
25 #define STATUS_E1_MASK		(1<<STATUS_E1_BIT)
26 #define STATUS_E2_MASK		(1<<STATUS_E2_BIT)
27 #define STATUS_A1_MASK		(1<<STATUS_A1_BIT)
28 #define STATUS_A2_MASK		(1<<STATUS_A2_BIT)
29 #define STATUS_AE_MASK		(1<<STATUS_AE_BIT)
30 #define STATUS_IE_MASK		(STATUS_E1_MASK | STATUS_E2_MASK)
31 
32 /* Other Interrupt Handling related Aux regs */
33 #define AUX_IRQ_LEV		0x200	/* IRQ Priority: L1 or L2 */
34 #define AUX_IRQ_HINT		0x201	/* For generating Soft Interrupts */
35 #define AUX_IRQ_LV12		0x43	/* interrupt level register */
36 
37 #define AUX_IENABLE		0x40c
38 #define AUX_ITRIGGER		0x40d
39 #define AUX_IPULSE		0x415
40 
41 #define ISA_INIT_STATUS_BITS	STATUS_IE_MASK
42 
43 #ifndef __ASSEMBLY__
44 
45 /******************************************************************
46  * IRQ Control Macros
47  *
48  * All of them have "memory" clobber (compiler barrier) which is needed to
49  * ensure that LD/ST requiring irq safety (R-M-W when LLSC is not available)
50  * are redone after IRQs are re-enabled (and gcc doesn't reuse stale register)
51  *
52  * Noted at the time of Abilis Timer List corruption
53  *
54  * Orig Bug + Rejected solution:
55  * https://lore.kernel.org/lkml/1364553218-31255-1-git-send-email-vgupta@synopsys.com
56  *
57  * Reasoning:
58  * https://lore.kernel.org/lkml/CA+55aFyFWjpSVQM6M266tKrG_ZXJzZ-nYejpmXYQXbrr42mGPQ@mail.gmail.com
59  *
60  ******************************************************************/
61 
62 /*
63  * Save IRQ state and disable IRQs
64  */
65 static inline long arch_local_irq_save(void)
66 {
67 	unsigned long temp, flags;
68 
69 	__asm__ __volatile__(
70 	"	lr  %1, [status32]	\n"
71 	"	bic %0, %1, %2		\n"
72 	"	and.f 0, %1, %2	\n"
73 	"	flag.nz %0		\n"
74 	: "=r"(temp), "=r"(flags)
75 	: "n"((STATUS_E1_MASK | STATUS_E2_MASK))
76 	: "memory", "cc");
77 
78 	return flags;
79 }
80 
81 /*
82  * restore saved IRQ state
83  */
84 static inline void arch_local_irq_restore(unsigned long flags)
85 {
86 
87 	__asm__ __volatile__(
88 	"	flag %0			\n"
89 	:
90 	: "r"(flags)
91 	: "memory");
92 }
93 
94 /*
95  * Unconditionally Enable IRQs
96  */
97 #ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
98 extern void arch_local_irq_enable(void);
99 #else
100 static inline void arch_local_irq_enable(void)
101 {
102 	unsigned long temp;
103 
104 	__asm__ __volatile__(
105 	"	lr   %0, [status32]	\n"
106 	"	or   %0, %0, %1		\n"
107 	"	flag %0			\n"
108 	: "=&r"(temp)
109 	: "n"((STATUS_E1_MASK | STATUS_E2_MASK))
110 	: "cc", "memory");
111 }
112 #endif
113 
114 /*
115  * Unconditionally Disable IRQs
116  */
117 static inline void arch_local_irq_disable(void)
118 {
119 	unsigned long temp;
120 
121 	__asm__ __volatile__(
122 	"	lr  %0, [status32]	\n"
123 	"	and %0, %0, %1		\n"
124 	"	flag %0			\n"
125 	: "=&r"(temp)
126 	: "n"(~(STATUS_E1_MASK | STATUS_E2_MASK))
127 	: "memory");
128 }
129 
130 /*
131  * save IRQ state
132  */
133 static inline long arch_local_save_flags(void)
134 {
135 	unsigned long temp;
136 
137 	__asm__ __volatile__(
138 	"	lr  %0, [status32]	\n"
139 	: "=&r"(temp)
140 	:
141 	: "memory");
142 
143 	return temp;
144 }
145 
146 /*
147  * Query IRQ state
148  */
149 static inline int arch_irqs_disabled_flags(unsigned long flags)
150 {
151 	return !(flags & (STATUS_E1_MASK
152 #ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
153 			| STATUS_E2_MASK
154 #endif
155 		));
156 }
157 
158 static inline int arch_irqs_disabled(void)
159 {
160 	return arch_irqs_disabled_flags(arch_local_save_flags());
161 }
162 
163 #else
164 
165 #ifdef CONFIG_TRACE_IRQFLAGS
166 
167 .macro TRACE_ASM_IRQ_DISABLE
168 	bl	trace_hardirqs_off
169 .endm
170 
171 .macro TRACE_ASM_IRQ_ENABLE
172 	bl	trace_hardirqs_on
173 .endm
174 
175 #else
176 
177 .macro TRACE_ASM_IRQ_DISABLE
178 .endm
179 
180 .macro TRACE_ASM_IRQ_ENABLE
181 .endm
182 
183 #endif
184 
185 .macro IRQ_DISABLE  scratch
186 	lr	\scratch, [status32]
187 	bic	\scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)
188 	flag	\scratch
189 	TRACE_ASM_IRQ_DISABLE
190 .endm
191 
192 .macro IRQ_ENABLE  scratch
193 	TRACE_ASM_IRQ_ENABLE
194 	lr	\scratch, [status32]
195 	or	\scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)
196 	flag	\scratch
197 .endm
198 
199 #endif	/* __ASSEMBLY__ */
200 
201 #endif
202