1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Common definitions across all variants of ICP and ICS interrupt
4  * controllers.
5  */
6 
7 #ifndef _XICS_H
8 #define _XICS_H
9 
10 #include <linux/interrupt.h>
11 
12 #define XICS_IPI		2
13 #define XICS_IRQ_SPURIOUS	0
14 
15 /* Want a priority other than 0.  Various HW issues require this. */
16 #define	DEFAULT_PRIORITY	5
17 
18 /*
19  * Mark IPIs as higher priority so we can take them inside interrupts
20  * FIXME: still true now?
21  */
22 #define IPI_PRIORITY		4
23 
24 /* The least favored priority */
25 #define LOWEST_PRIORITY		0xFF
26 
27 /* The number of priorities defined above */
28 #define MAX_NUM_PRIORITIES	3
29 
30 /* Native ICP */
31 #ifdef CONFIG_PPC_ICP_NATIVE
32 extern int icp_native_init(void);
33 extern void icp_native_flush_interrupt(void);
34 extern void icp_native_cause_ipi_rm(int cpu);
35 #else
icp_native_init(void)36 static inline int icp_native_init(void) { return -ENODEV; }
37 #endif
38 
39 /* PAPR ICP */
40 #ifdef CONFIG_PPC_ICP_HV
41 extern int icp_hv_init(void);
42 #else
icp_hv_init(void)43 static inline int icp_hv_init(void) { return -ENODEV; }
44 #endif
45 
46 #ifdef CONFIG_PPC_POWERNV
47 extern int icp_opal_init(void);
48 extern void icp_opal_flush_interrupt(void);
49 #else
icp_opal_init(void)50 static inline int icp_opal_init(void) { return -ENODEV; }
51 #endif
52 
53 /* ICP ops */
54 struct icp_ops {
55 	unsigned int (*get_irq)(void);
56 	void (*eoi)(struct irq_data *d);
57 	void (*set_priority)(unsigned char prio);
58 	void (*teardown_cpu)(void);
59 	void (*flush_ipi)(void);
60 #ifdef CONFIG_SMP
61 	void (*cause_ipi)(int cpu);
62 	irq_handler_t ipi_action;
63 #endif
64 };
65 
66 extern const struct icp_ops *icp_ops;
67 
68 /* Native ICS */
69 extern int ics_native_init(void);
70 
71 /* RTAS ICS */
72 #ifdef CONFIG_PPC_ICS_RTAS
73 extern int ics_rtas_init(void);
74 #else
ics_rtas_init(void)75 static inline int ics_rtas_init(void) { return -ENODEV; }
76 #endif
77 
78 /* HAL ICS */
79 #ifdef CONFIG_PPC_POWERNV
80 extern int ics_opal_init(void);
81 #else
ics_opal_init(void)82 static inline int ics_opal_init(void) { return -ENODEV; }
83 #endif
84 
85 /* ICS instance, hooked up to chip_data of an irq */
86 struct ics {
87 	struct list_head link;
88 	int (*map)(struct ics *ics, unsigned int virq);
89 	void (*mask_unknown)(struct ics *ics, unsigned long vec);
90 	long (*get_server)(struct ics *ics, unsigned long vec);
91 	int (*host_match)(struct ics *ics, struct device_node *node);
92 	char data[];
93 };
94 
95 /* Commons */
96 extern unsigned int xics_default_server;
97 extern unsigned int xics_default_distrib_server;
98 extern unsigned int xics_interrupt_server_size;
99 extern struct irq_domain *xics_host;
100 
101 struct xics_cppr {
102 	unsigned char stack[MAX_NUM_PRIORITIES];
103 	int index;
104 };
105 
106 DECLARE_PER_CPU(struct xics_cppr, xics_cppr);
107 
xics_push_cppr(unsigned int vec)108 static inline void xics_push_cppr(unsigned int vec)
109 {
110 	struct xics_cppr *os_cppr = this_cpu_ptr(&xics_cppr);
111 
112 	if (WARN_ON(os_cppr->index >= MAX_NUM_PRIORITIES - 1))
113 		return;
114 
115 	if (vec == XICS_IPI)
116 		os_cppr->stack[++os_cppr->index] = IPI_PRIORITY;
117 	else
118 		os_cppr->stack[++os_cppr->index] = DEFAULT_PRIORITY;
119 }
120 
xics_pop_cppr(void)121 static inline unsigned char xics_pop_cppr(void)
122 {
123 	struct xics_cppr *os_cppr = this_cpu_ptr(&xics_cppr);
124 
125 	if (WARN_ON(os_cppr->index < 1))
126 		return LOWEST_PRIORITY;
127 
128 	return os_cppr->stack[--os_cppr->index];
129 }
130 
xics_set_base_cppr(unsigned char cppr)131 static inline void xics_set_base_cppr(unsigned char cppr)
132 {
133 	struct xics_cppr *os_cppr = this_cpu_ptr(&xics_cppr);
134 
135 	/* we only really want to set the priority when there's
136 	 * just one cppr value on the stack
137 	 */
138 	WARN_ON(os_cppr->index != 0);
139 
140 	os_cppr->stack[0] = cppr;
141 }
142 
xics_cppr_top(void)143 static inline unsigned char xics_cppr_top(void)
144 {
145 	struct xics_cppr *os_cppr = this_cpu_ptr(&xics_cppr);
146 
147 	return os_cppr->stack[os_cppr->index];
148 }
149 
150 DECLARE_PER_CPU_SHARED_ALIGNED(unsigned long, xics_ipi_message);
151 
152 extern void xics_init(void);
153 extern void xics_setup_cpu(void);
154 extern void xics_update_irq_servers(void);
155 extern void xics_set_cpu_giq(unsigned int gserver, unsigned int join);
156 extern void xics_mask_unknown_vec(unsigned int vec);
157 extern irqreturn_t xics_ipi_dispatch(int cpu);
158 extern void xics_smp_probe(void);
159 extern void xics_register_ics(struct ics *ics);
160 extern void xics_teardown_cpu(void);
161 extern void xics_kexec_teardown_cpu(int secondary);
162 extern void xics_migrate_irqs_away(void);
163 extern void icp_native_eoi(struct irq_data *d);
164 extern int xics_set_irq_type(struct irq_data *d, unsigned int flow_type);
165 extern int xics_retrigger(struct irq_data *data);
166 #ifdef CONFIG_SMP
167 extern int xics_get_irq_server(unsigned int virq, const struct cpumask *cpumask,
168 			       unsigned int strict_check);
169 #else
170 #define xics_get_irq_server(virq, cpumask, strict_check) (xics_default_server)
171 #endif
172 
173 
174 #endif /* _XICS_H */
175