1 /*
2  * include/asm/irqflags.h
3  *
4  * IRQ flags handling
5  *
6  * This file gets included from lowlevel asm headers too, to provide
7  * wrapped versions of the local_irq_*() APIs, based on the
8  * arch_local_irq_*() functions from the lowlevel headers.
9  */
10 #ifndef _ASM_IRQFLAGS_H
11 #define _ASM_IRQFLAGS_H
12 
13 #include <asm/pil.h>
14 
15 #ifndef __ASSEMBLY__
16 
17 static inline notrace unsigned long arch_local_save_flags(void)
18 {
19 	unsigned long flags;
20 
21 	__asm__ __volatile__(
22 		"rdpr	%%pil, %0"
23 		: "=r" (flags)
24 	);
25 
26 	return flags;
27 }
28 
29 static inline notrace void arch_local_irq_restore(unsigned long flags)
30 {
31 	__asm__ __volatile__(
32 		"wrpr	%0, %%pil"
33 		: /* no output */
34 		: "r" (flags)
35 		: "memory"
36 	);
37 }
38 
39 static inline notrace void arch_local_irq_disable(void)
40 {
41 	__asm__ __volatile__(
42 		"wrpr	%0, %%pil"
43 		: /* no outputs */
44 		: "i" (PIL_NORMAL_MAX)
45 		: "memory"
46 	);
47 }
48 
49 static inline notrace void arch_local_irq_enable(void)
50 {
51 	__asm__ __volatile__(
52 		"wrpr	0, %%pil"
53 		: /* no outputs */
54 		: /* no inputs */
55 		: "memory"
56 	);
57 }
58 
59 static inline notrace int arch_irqs_disabled_flags(unsigned long flags)
60 {
61 	return (flags > 0);
62 }
63 
64 static inline notrace int arch_irqs_disabled(void)
65 {
66 	return arch_irqs_disabled_flags(arch_local_save_flags());
67 }
68 
69 static inline notrace unsigned long arch_local_irq_save(void)
70 {
71 	unsigned long flags, tmp;
72 
73 	/* Disable interrupts to PIL_NORMAL_MAX unless we already
74 	 * are using PIL_NMI, in which case PIL_NMI is retained.
75 	 *
76 	 * The only values we ever program into the %pil are 0,
77 	 * PIL_NORMAL_MAX and PIL_NMI.
78 	 *
79 	 * Since PIL_NMI is the largest %pil value and all bits are
80 	 * set in it (0xf), it doesn't matter what PIL_NORMAL_MAX
81 	 * actually is.
82 	 */
83 	__asm__ __volatile__(
84 		"rdpr	%%pil, %0\n\t"
85 		"or	%0, %2, %1\n\t"
86 		"wrpr	%1, 0x0, %%pil"
87 		: "=r" (flags), "=r" (tmp)
88 		: "i" (PIL_NORMAL_MAX)
89 		: "memory"
90 	);
91 
92 	return flags;
93 }
94 
95 #endif /* (__ASSEMBLY__) */
96 
97 #endif /* !(_ASM_IRQFLAGS_H) */
98