xref: /linux/include/linux/irqchip/arm-gic-v3-prio.h (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 
3 #ifndef __LINUX_IRQCHIP_ARM_GIC_V3_PRIO_H
4 #define __LINUX_IRQCHIP_ARM_GIC_V3_PRIO_H
5 
6 /*
7  * GIC priorities from the view of the PMR/RPR.
8  *
9  * These values are chosen to be valid in either the absolute priority space or
10  * the NS view of the priority space. The value programmed into the distributor
11  * and ITS will be chosen at boot time such that these values appear in the
12  * PMR/RPR.
13  *
14  * GICV3_PRIO_UNMASKED is the PMR view of the priority to use to permit both
15  * IRQs and pseudo-NMIs.
16  *
17  * GICV3_PRIO_IRQ is the PMR view of the priority of regular interrupts. This
18  * can be written to the PMR to mask regular IRQs.
19  *
20  * GICV3_PRIO_NMI is the PMR view of the priority of pseudo-NMIs. This can be
21  * written to the PMR to mask pseudo-NMIs.
22  *
23  * On arm64 some code sections either automatically switch back to PSR.I or
24  * explicitly require to not use priority masking. If bit GICV3_PRIO_PSR_I_SET
25  * is included in the priority mask, it indicates that PSR.I should be set and
26  * interrupt disabling temporarily does not rely on IRQ priorities.
27  */
28 #define GICV3_PRIO_UNMASKED	0xe0
29 #define GICV3_PRIO_IRQ		0xc0
30 #define GICV3_PRIO_NMI		0x80
31 
32 #define GICV3_PRIO_PSR_I_SET	(1 << 4)
33 
34 #ifndef __ASSEMBLER__
35 
36 #define __gicv3_prio_to_ns(p)	(0xff & ((p) << 1))
37 #define __gicv3_ns_to_prio(ns)	(0x80 | ((ns) >> 1))
38 
39 #define __gicv3_prio_valid_ns(p) \
40 	(__gicv3_ns_to_prio(__gicv3_prio_to_ns(p)) == (p))
41 
42 static_assert(__gicv3_prio_valid_ns(GICV3_PRIO_NMI));
43 static_assert(__gicv3_prio_valid_ns(GICV3_PRIO_IRQ));
44 
45 static_assert(GICV3_PRIO_NMI < GICV3_PRIO_IRQ);
46 static_assert(GICV3_PRIO_IRQ < GICV3_PRIO_UNMASKED);
47 
48 static_assert(GICV3_PRIO_IRQ < (GICV3_PRIO_IRQ | GICV3_PRIO_PSR_I_SET));
49 
50 #endif /* __ASSEMBLER */
51 
52 #endif /* __LINUX_IRQCHIP_ARM_GIC_V3_PRIO_H */
53