xref: /openbmc/qemu/include/hw/intc/armv7m_nvic.h (revision 750541c4)
1 /*
2  * ARMv7M NVIC object
3  *
4  * Copyright (c) 2017 Linaro Ltd
5  * Written by Peter Maydell <peter.maydell@linaro.org>
6  *
7  * This code is licensed under the GPL version 2 or later.
8  */
9 
10 #ifndef HW_ARM_ARMV7M_NVIC_H
11 #define HW_ARM_ARMV7M_NVIC_H
12 
13 #include "target/arm/cpu.h"
14 #include "hw/sysbus.h"
15 #include "hw/timer/armv7m_systick.h"
16 
17 #define TYPE_NVIC "armv7m_nvic"
18 
19 #define NVIC(obj) \
20     OBJECT_CHECK(NVICState, (obj), TYPE_NVIC)
21 
22 /* Highest permitted number of exceptions (architectural limit) */
23 #define NVIC_MAX_VECTORS 512
24 /* Number of internal exceptions */
25 #define NVIC_INTERNAL_VECTORS 16
26 
27 typedef struct VecInfo {
28     /* Exception priorities can range from -3 to 255; only the unmodifiable
29      * priority values for RESET, NMI and HardFault can be negative.
30      */
31     int16_t prio;
32     uint8_t enabled;
33     uint8_t pending;
34     uint8_t active;
35     uint8_t level; /* exceptions <=15 never set level */
36 } VecInfo;
37 
38 typedef struct NVICState {
39     /*< private >*/
40     SysBusDevice parent_obj;
41     /*< public >*/
42 
43     ARMCPU *cpu;
44 
45     VecInfo vectors[NVIC_MAX_VECTORS];
46     /* If the v8M security extension is implemented, some of the internal
47      * exceptions are banked between security states (ie there exists both
48      * a Secure and a NonSecure version of the exception and its state):
49      *  HardFault, MemManage, UsageFault, SVCall, PendSV, SysTick (R_PJHV)
50      * The rest (including all the external exceptions) are not banked, though
51      * they may be configurable to target either Secure or NonSecure state.
52      * We store the secure exception state in sec_vectors[] for the banked
53      * exceptions, and otherwise use only vectors[] (including for exceptions
54      * like SecureFault that unconditionally target Secure state).
55      * Entries in sec_vectors[] for non-banked exception numbers are unused.
56      */
57     VecInfo sec_vectors[NVIC_INTERNAL_VECTORS];
58     /* The PRIGROUP field in AIRCR is banked */
59     uint32_t prigroup[M_REG_NUM_BANKS];
60     uint8_t num_prio_bits;
61 
62     /* v8M NVIC_ITNS state (stored as a bool per bit) */
63     bool itns[NVIC_MAX_VECTORS];
64 
65     /* The following fields are all cached state that can be recalculated
66      * from the vectors[] and sec_vectors[] arrays and the prigroup field:
67      *  - vectpending
68      *  - vectpending_is_secure
69      *  - exception_prio
70      *  - vectpending_prio
71      */
72     unsigned int vectpending; /* highest prio pending enabled exception */
73     /* true if vectpending is a banked secure exception, ie it is in
74      * sec_vectors[] rather than vectors[]
75      */
76     bool vectpending_is_s_banked;
77     int exception_prio; /* group prio of the highest prio active exception */
78     int vectpending_prio; /* group prio of the exeception in vectpending */
79 
80     MemoryRegion sysregmem;
81     MemoryRegion sysreg_ns_mem;
82     MemoryRegion systickmem;
83     MemoryRegion systick_ns_mem;
84     MemoryRegion container;
85 
86     uint32_t num_irq;
87     qemu_irq excpout;
88     qemu_irq sysresetreq;
89 
90     SysTickState systick[M_REG_NUM_BANKS];
91 } NVICState;
92 
93 #endif
94