xref: /openbmc/linux/arch/powerpc/include/asm/hw_irq.h (revision add48ba4)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
4  */
5 #ifndef _ASM_POWERPC_HW_IRQ_H
6 #define _ASM_POWERPC_HW_IRQ_H
7 
8 #ifdef __KERNEL__
9 
10 #include <linux/errno.h>
11 #include <linux/compiler.h>
12 #include <asm/ptrace.h>
13 #include <asm/processor.h>
14 
15 #ifdef CONFIG_PPC64
16 
17 /*
18  * PACA flags in paca->irq_happened.
19  *
20  * This bits are set when interrupts occur while soft-disabled
21  * and allow a proper replay. Additionally, PACA_IRQ_HARD_DIS
22  * is set whenever we manually hard disable.
23  */
24 #define PACA_IRQ_HARD_DIS	0x01
25 #define PACA_IRQ_DBELL		0x02
26 #define PACA_IRQ_EE		0x04
27 #define PACA_IRQ_DEC		0x08 /* Or FIT */
28 #define PACA_IRQ_EE_EDGE	0x10 /* BookE only */
29 #define PACA_IRQ_HMI		0x20
30 #define PACA_IRQ_PMI		0x40
31 
32 /*
33  * Some soft-masked interrupts must be hard masked until they are replayed
34  * (e.g., because the soft-masked handler does not clear the exception).
35  */
36 #ifdef CONFIG_PPC_BOOK3S
37 #define PACA_IRQ_MUST_HARD_MASK	(PACA_IRQ_EE|PACA_IRQ_PMI)
38 #else
39 #define PACA_IRQ_MUST_HARD_MASK	(PACA_IRQ_EE)
40 #endif
41 
42 /*
43  * flags for paca->irq_soft_mask
44  */
45 #define IRQS_ENABLED		0
46 #define IRQS_DISABLED		1 /* local_irq_disable() interrupts */
47 #define IRQS_PMI_DISABLED	2
48 #define IRQS_ALL_DISABLED	(IRQS_DISABLED | IRQS_PMI_DISABLED)
49 
50 #endif /* CONFIG_PPC64 */
51 
52 #ifndef __ASSEMBLY__
53 
54 extern void replay_system_reset(void);
55 extern void replay_soft_interrupts(void);
56 
57 extern void timer_interrupt(struct pt_regs *);
58 extern void timer_broadcast_interrupt(void);
59 extern void performance_monitor_exception(struct pt_regs *regs);
60 extern void WatchdogException(struct pt_regs *regs);
61 extern void unknown_exception(struct pt_regs *regs);
62 
63 #ifdef CONFIG_PPC64
64 #include <asm/paca.h>
65 
66 static inline notrace unsigned long irq_soft_mask_return(void)
67 {
68 	unsigned long flags;
69 
70 	asm volatile(
71 		"lbz %0,%1(13)"
72 		: "=r" (flags)
73 		: "i" (offsetof(struct paca_struct, irq_soft_mask)));
74 
75 	return flags;
76 }
77 
78 /*
79  * The "memory" clobber acts as both a compiler barrier
80  * for the critical section and as a clobber because
81  * we changed paca->irq_soft_mask
82  */
83 static inline notrace void irq_soft_mask_set(unsigned long mask)
84 {
85 #ifdef CONFIG_PPC_IRQ_SOFT_MASK_DEBUG
86 	/*
87 	 * The irq mask must always include the STD bit if any are set.
88 	 *
89 	 * and interrupts don't get replayed until the standard
90 	 * interrupt (local_irq_disable()) is unmasked.
91 	 *
92 	 * Other masks must only provide additional masking beyond
93 	 * the standard, and they are also not replayed until the
94 	 * standard interrupt becomes unmasked.
95 	 *
96 	 * This could be changed, but it will require partial
97 	 * unmasks to be replayed, among other things. For now, take
98 	 * the simple approach.
99 	 */
100 	WARN_ON(mask && !(mask & IRQS_DISABLED));
101 #endif
102 
103 	asm volatile(
104 		"stb %0,%1(13)"
105 		:
106 		: "r" (mask),
107 		  "i" (offsetof(struct paca_struct, irq_soft_mask))
108 		: "memory");
109 }
110 
111 static inline notrace unsigned long irq_soft_mask_set_return(unsigned long mask)
112 {
113 	unsigned long flags;
114 
115 #ifdef CONFIG_PPC_IRQ_SOFT_MASK_DEBUG
116 	WARN_ON(mask && !(mask & IRQS_DISABLED));
117 #endif
118 
119 	asm volatile(
120 		"lbz %0,%1(13); stb %2,%1(13)"
121 		: "=&r" (flags)
122 		: "i" (offsetof(struct paca_struct, irq_soft_mask)),
123 		  "r" (mask)
124 		: "memory");
125 
126 	return flags;
127 }
128 
129 static inline notrace unsigned long irq_soft_mask_or_return(unsigned long mask)
130 {
131 	unsigned long flags, tmp;
132 
133 	asm volatile(
134 		"lbz %0,%2(13); or %1,%0,%3; stb %1,%2(13)"
135 		: "=&r" (flags), "=r" (tmp)
136 		: "i" (offsetof(struct paca_struct, irq_soft_mask)),
137 		  "r" (mask)
138 		: "memory");
139 
140 #ifdef CONFIG_PPC_IRQ_SOFT_MASK_DEBUG
141 	WARN_ON((mask | flags) && !((mask | flags) & IRQS_DISABLED));
142 #endif
143 
144 	return flags;
145 }
146 
147 static inline unsigned long arch_local_save_flags(void)
148 {
149 	return irq_soft_mask_return();
150 }
151 
152 static inline void arch_local_irq_disable(void)
153 {
154 	irq_soft_mask_set(IRQS_DISABLED);
155 }
156 
157 extern void arch_local_irq_restore(unsigned long);
158 
159 static inline void arch_local_irq_enable(void)
160 {
161 	arch_local_irq_restore(IRQS_ENABLED);
162 }
163 
164 static inline unsigned long arch_local_irq_save(void)
165 {
166 	return irq_soft_mask_set_return(IRQS_DISABLED);
167 }
168 
169 static inline bool arch_irqs_disabled_flags(unsigned long flags)
170 {
171 	return flags & IRQS_DISABLED;
172 }
173 
174 static inline bool arch_irqs_disabled(void)
175 {
176 	return arch_irqs_disabled_flags(arch_local_save_flags());
177 }
178 
179 #ifdef CONFIG_PPC_BOOK3S
180 /*
181  * To support disabling and enabling of irq with PMI, set of
182  * new powerpc_local_irq_pmu_save() and powerpc_local_irq_restore()
183  * functions are added. These macros are implemented using generic
184  * linux local_irq_* code from include/linux/irqflags.h.
185  */
186 #define raw_local_irq_pmu_save(flags)					\
187 	do {								\
188 		typecheck(unsigned long, flags);			\
189 		flags = irq_soft_mask_or_return(IRQS_DISABLED |	\
190 				IRQS_PMI_DISABLED);			\
191 	} while(0)
192 
193 #define raw_local_irq_pmu_restore(flags)				\
194 	do {								\
195 		typecheck(unsigned long, flags);			\
196 		arch_local_irq_restore(flags);				\
197 	} while(0)
198 
199 #ifdef CONFIG_TRACE_IRQFLAGS
200 #define powerpc_local_irq_pmu_save(flags)			\
201 	 do {							\
202 		raw_local_irq_pmu_save(flags);			\
203 		trace_hardirqs_off();				\
204 	} while(0)
205 #define powerpc_local_irq_pmu_restore(flags)			\
206 	do {							\
207 		if (raw_irqs_disabled_flags(flags)) {		\
208 			raw_local_irq_pmu_restore(flags);	\
209 			trace_hardirqs_off();			\
210 		} else {					\
211 			trace_hardirqs_on();			\
212 			raw_local_irq_pmu_restore(flags);	\
213 		}						\
214 	} while(0)
215 #else
216 #define powerpc_local_irq_pmu_save(flags)			\
217 	do {							\
218 		raw_local_irq_pmu_save(flags);			\
219 	} while(0)
220 #define powerpc_local_irq_pmu_restore(flags)			\
221 	do {							\
222 		raw_local_irq_pmu_restore(flags);		\
223 	} while (0)
224 #endif  /* CONFIG_TRACE_IRQFLAGS */
225 
226 #endif /* CONFIG_PPC_BOOK3S */
227 
228 #ifdef CONFIG_PPC_BOOK3E
229 #define __hard_irq_enable()	wrtee(MSR_EE)
230 #define __hard_irq_disable()	wrtee(0)
231 #define __hard_EE_RI_disable()	wrtee(0)
232 #define __hard_RI_enable()	do { } while (0)
233 #else
234 #define __hard_irq_enable()	__mtmsrd(MSR_EE|MSR_RI, 1)
235 #define __hard_irq_disable()	__mtmsrd(MSR_RI, 1)
236 #define __hard_EE_RI_disable()	__mtmsrd(0, 1)
237 #define __hard_RI_enable()	__mtmsrd(MSR_RI, 1)
238 #endif
239 
240 #define hard_irq_disable()	do {					\
241 	unsigned long flags;						\
242 	__hard_irq_disable();						\
243 	flags = irq_soft_mask_set_return(IRQS_ALL_DISABLED);		\
244 	local_paca->irq_happened |= PACA_IRQ_HARD_DIS;			\
245 	if (!arch_irqs_disabled_flags(flags)) {				\
246 		asm ("stdx %%r1, 0, %1 ;"				\
247 		     : "=m" (local_paca->saved_r1)			\
248 		     : "b" (&local_paca->saved_r1));			\
249 		trace_hardirqs_off();					\
250 	}								\
251 } while(0)
252 
253 static inline bool __lazy_irq_pending(u8 irq_happened)
254 {
255 	return !!(irq_happened & ~PACA_IRQ_HARD_DIS);
256 }
257 
258 /*
259  * Check if a lazy IRQ is pending. Should be called with IRQs hard disabled.
260  */
261 static inline bool lazy_irq_pending(void)
262 {
263 	return __lazy_irq_pending(get_paca()->irq_happened);
264 }
265 
266 /*
267  * Check if a lazy IRQ is pending, with no debugging checks.
268  * Should be called with IRQs hard disabled.
269  * For use in RI disabled code or other constrained situations.
270  */
271 static inline bool lazy_irq_pending_nocheck(void)
272 {
273 	return __lazy_irq_pending(local_paca->irq_happened);
274 }
275 
276 /*
277  * This is called by asynchronous interrupts to conditionally
278  * re-enable hard interrupts after having cleared the source
279  * of the interrupt. They are kept disabled if there is a different
280  * soft-masked interrupt pending that requires hard masking.
281  */
282 static inline void may_hard_irq_enable(void)
283 {
284 	if (!(get_paca()->irq_happened & PACA_IRQ_MUST_HARD_MASK)) {
285 		get_paca()->irq_happened &= ~PACA_IRQ_HARD_DIS;
286 		__hard_irq_enable();
287 	}
288 }
289 
290 static inline bool arch_irq_disabled_regs(struct pt_regs *regs)
291 {
292 	return (regs->softe & IRQS_DISABLED);
293 }
294 
295 extern bool prep_irq_for_idle(void);
296 extern bool prep_irq_for_idle_irqsoff(void);
297 extern void irq_set_pending_from_srr1(unsigned long srr1);
298 
299 #define fini_irq_for_idle_irqsoff() trace_hardirqs_off();
300 
301 extern void force_external_irq_replay(void);
302 
303 #else /* CONFIG_PPC64 */
304 
305 static inline unsigned long arch_local_save_flags(void)
306 {
307 	return mfmsr();
308 }
309 
310 static inline void arch_local_irq_restore(unsigned long flags)
311 {
312 	if (IS_ENABLED(CONFIG_BOOKE))
313 		wrtee(flags);
314 	else
315 		mtmsr(flags);
316 }
317 
318 static inline unsigned long arch_local_irq_save(void)
319 {
320 	unsigned long flags = arch_local_save_flags();
321 
322 	if (IS_ENABLED(CONFIG_BOOKE))
323 		wrtee(0);
324 	else if (IS_ENABLED(CONFIG_PPC_8xx))
325 		wrtspr(SPRN_EID);
326 	else
327 		mtmsr(flags & ~MSR_EE);
328 
329 	return flags;
330 }
331 
332 static inline void arch_local_irq_disable(void)
333 {
334 	if (IS_ENABLED(CONFIG_BOOKE))
335 		wrtee(0);
336 	else if (IS_ENABLED(CONFIG_PPC_8xx))
337 		wrtspr(SPRN_EID);
338 	else
339 		mtmsr(mfmsr() & ~MSR_EE);
340 }
341 
342 static inline void arch_local_irq_enable(void)
343 {
344 	if (IS_ENABLED(CONFIG_BOOKE))
345 		wrtee(MSR_EE);
346 	else if (IS_ENABLED(CONFIG_PPC_8xx))
347 		wrtspr(SPRN_EIE);
348 	else
349 		mtmsr(mfmsr() | MSR_EE);
350 }
351 
352 static inline bool arch_irqs_disabled_flags(unsigned long flags)
353 {
354 	return (flags & MSR_EE) == 0;
355 }
356 
357 static inline bool arch_irqs_disabled(void)
358 {
359 	return arch_irqs_disabled_flags(arch_local_save_flags());
360 }
361 
362 #define hard_irq_disable()		arch_local_irq_disable()
363 
364 static inline bool arch_irq_disabled_regs(struct pt_regs *regs)
365 {
366 	return !(regs->msr & MSR_EE);
367 }
368 
369 static inline void may_hard_irq_enable(void) { }
370 
371 #endif /* CONFIG_PPC64 */
372 
373 #define ARCH_IRQ_INIT_FLAGS	IRQ_NOREQUEST
374 
375 /*
376  * interrupt-retrigger: should we handle this via lost interrupts and IPIs
377  * or should we not care like we do now ? --BenH.
378  */
379 struct irq_chip;
380 
381 #endif  /* __ASSEMBLY__ */
382 #endif	/* __KERNEL__ */
383 #endif	/* _ASM_POWERPC_HW_IRQ_H */
384