1/*
2 * Copyright 2010 Tilera Corporation. All Rights Reserved.
3 *
4 *   This program is free software; you can redistribute it and/or
5 *   modify it under the terms of the GNU General Public License
6 *   as published by the Free Software Foundation, version 2.
7 *
8 *   This program is distributed in the hope that it will be useful, but
9 *   WITHOUT ANY WARRANTY; without even the implied warranty of
10 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11 *   NON INFRINGEMENT.  See the GNU General Public License for
12 *   more details.
13 */
14
15#ifndef _ASM_TILE_IRQFLAGS_H
16#define _ASM_TILE_IRQFLAGS_H
17
18#include <arch/interrupts.h>
19#include <arch/chip.h>
20
21/*
22 * The set of interrupts we want to allow when interrupts are nominally
23 * disabled.  The remainder are effectively "NMI" interrupts from
24 * the point of view of the generic Linux code.  Note that synchronous
25 * interrupts (aka "non-queued") are not blocked by the mask in any case.
26 */
27#define LINUX_MASKABLE_INTERRUPTS \
28	(~((_AC(1,ULL) << INT_PERF_COUNT) | (_AC(1,ULL) << INT_AUX_PERF_COUNT)))
29
30#if CHIP_HAS_SPLIT_INTR_MASK()
31/* The same macro, but for the two 32-bit SPRs separately. */
32#define LINUX_MASKABLE_INTERRUPTS_LO (-1)
33#define LINUX_MASKABLE_INTERRUPTS_HI \
34	(~((1 << (INT_PERF_COUNT - 32)) | (1 << (INT_AUX_PERF_COUNT - 32))))
35#endif
36
37#ifndef __ASSEMBLY__
38
39/* NOTE: we can't include <linux/percpu.h> due to #include dependencies. */
40#include <asm/percpu.h>
41#include <arch/spr_def.h>
42
43/*
44 * Set and clear kernel interrupt masks.
45 *
46 * NOTE: __insn_mtspr() is a compiler builtin marked as a memory
47 * clobber.  We rely on it being equivalent to a compiler barrier in
48 * this code since arch_local_irq_save() and friends must act as
49 * compiler barriers.  This compiler semantic is baked into enough
50 * places that the compiler will maintain it going forward.
51 */
52#if CHIP_HAS_SPLIT_INTR_MASK()
53#if INT_PERF_COUNT < 32 || INT_AUX_PERF_COUNT < 32 || INT_MEM_ERROR >= 32
54# error Fix assumptions about which word various interrupts are in
55#endif
56#define interrupt_mask_set(n) do { \
57	int __n = (n); \
58	int __mask = 1 << (__n & 0x1f); \
59	if (__n < 32) \
60		__insn_mtspr(SPR_INTERRUPT_MASK_SET_K_0, __mask); \
61	else \
62		__insn_mtspr(SPR_INTERRUPT_MASK_SET_K_1, __mask); \
63} while (0)
64#define interrupt_mask_reset(n) do { \
65	int __n = (n); \
66	int __mask = 1 << (__n & 0x1f); \
67	if (__n < 32) \
68		__insn_mtspr(SPR_INTERRUPT_MASK_RESET_K_0, __mask); \
69	else \
70		__insn_mtspr(SPR_INTERRUPT_MASK_RESET_K_1, __mask); \
71} while (0)
72#define interrupt_mask_check(n) ({ \
73	int __n = (n); \
74	(((__n < 32) ? \
75	 __insn_mfspr(SPR_INTERRUPT_MASK_K_0) : \
76	 __insn_mfspr(SPR_INTERRUPT_MASK_K_1)) \
77	  >> (__n & 0x1f)) & 1; \
78})
79#define interrupt_mask_set_mask(mask) do { \
80	unsigned long long __m = (mask); \
81	__insn_mtspr(SPR_INTERRUPT_MASK_SET_K_0, (unsigned long)(__m)); \
82	__insn_mtspr(SPR_INTERRUPT_MASK_SET_K_1, (unsigned long)(__m>>32)); \
83} while (0)
84#define interrupt_mask_reset_mask(mask) do { \
85	unsigned long long __m = (mask); \
86	__insn_mtspr(SPR_INTERRUPT_MASK_RESET_K_0, (unsigned long)(__m)); \
87	__insn_mtspr(SPR_INTERRUPT_MASK_RESET_K_1, (unsigned long)(__m>>32)); \
88} while (0)
89#define interrupt_mask_save_mask() \
90	(__insn_mfspr(SPR_INTERRUPT_MASK_SET_K_0) | \
91	 (((unsigned long long)__insn_mfspr(SPR_INTERRUPT_MASK_SET_K_1))<<32))
92#define interrupt_mask_restore_mask(mask) do { \
93	unsigned long long __m = (mask); \
94	__insn_mtspr(SPR_INTERRUPT_MASK_K_0, (unsigned long)(__m)); \
95	__insn_mtspr(SPR_INTERRUPT_MASK_K_1, (unsigned long)(__m>>32)); \
96} while (0)
97#else
98#define interrupt_mask_set(n) \
99	__insn_mtspr(SPR_INTERRUPT_MASK_SET_K, (1UL << (n)))
100#define interrupt_mask_reset(n) \
101	__insn_mtspr(SPR_INTERRUPT_MASK_RESET_K, (1UL << (n)))
102#define interrupt_mask_check(n) \
103	((__insn_mfspr(SPR_INTERRUPT_MASK_K) >> (n)) & 1)
104#define interrupt_mask_set_mask(mask) \
105	__insn_mtspr(SPR_INTERRUPT_MASK_SET_K, (mask))
106#define interrupt_mask_reset_mask(mask) \
107	__insn_mtspr(SPR_INTERRUPT_MASK_RESET_K, (mask))
108#define interrupt_mask_save_mask() \
109	__insn_mfspr(SPR_INTERRUPT_MASK_K)
110#define interrupt_mask_restore_mask(mask) \
111	__insn_mtspr(SPR_INTERRUPT_MASK_K, (mask))
112#endif
113
114/*
115 * The set of interrupts we want active if irqs are enabled.
116 * Note that in particular, the tile timer interrupt comes and goes
117 * from this set, since we have no other way to turn off the timer.
118 * Likewise, INTCTRL_K is removed and re-added during device
119 * interrupts, as is the the hardwall UDN_FIREWALL interrupt.
120 * We use a low bit (MEM_ERROR) as our sentinel value and make sure it
121 * is always claimed as an "active interrupt" so we can query that bit
122 * to know our current state.
123 */
124DECLARE_PER_CPU(unsigned long long, interrupts_enabled_mask);
125#define INITIAL_INTERRUPTS_ENABLED (1ULL << INT_MEM_ERROR)
126
127#ifdef CONFIG_DEBUG_PREEMPT
128/* Due to inclusion issues, we can't rely on <linux/smp.h> here. */
129extern unsigned int debug_smp_processor_id(void);
130# define smp_processor_id() debug_smp_processor_id()
131#endif
132
133/* Disable interrupts. */
134#define arch_local_irq_disable() \
135	interrupt_mask_set_mask(LINUX_MASKABLE_INTERRUPTS)
136
137/* Disable all interrupts, including NMIs. */
138#define arch_local_irq_disable_all() \
139	interrupt_mask_set_mask(-1ULL)
140
141/*
142 * Read the set of maskable interrupts.
143 * We avoid the preemption warning here via raw_cpu_ptr since even
144 * if irqs are already enabled, it's harmless to read the wrong cpu's
145 * enabled mask.
146 */
147#define arch_local_irqs_enabled() \
148	(*raw_cpu_ptr(&interrupts_enabled_mask))
149
150/* Re-enable all maskable interrupts. */
151#define arch_local_irq_enable() \
152	interrupt_mask_reset_mask(arch_local_irqs_enabled())
153
154/* Disable or enable interrupts based on flag argument. */
155#define arch_local_irq_restore(disabled) do { \
156	if (disabled) \
157		arch_local_irq_disable(); \
158	else \
159		arch_local_irq_enable(); \
160} while (0)
161
162/* Return true if "flags" argument means interrupts are disabled. */
163#define arch_irqs_disabled_flags(flags) ((flags) != 0)
164
165/* Return true if interrupts are currently disabled. */
166#define arch_irqs_disabled() interrupt_mask_check(INT_MEM_ERROR)
167
168/* Save whether interrupts are currently disabled. */
169#define arch_local_save_flags() arch_irqs_disabled()
170
171/* Save whether interrupts are currently disabled, then disable them. */
172#define arch_local_irq_save() ({ \
173	unsigned long __flags = arch_local_save_flags(); \
174	arch_local_irq_disable(); \
175	__flags; })
176
177/* Prevent the given interrupt from being enabled next time we enable irqs. */
178#define arch_local_irq_mask(interrupt) \
179	this_cpu_and(interrupts_enabled_mask, ~(1ULL << (interrupt)))
180
181/* Prevent the given interrupt from being enabled immediately. */
182#define arch_local_irq_mask_now(interrupt) do { \
183	arch_local_irq_mask(interrupt); \
184	interrupt_mask_set(interrupt); \
185} while (0)
186
187/* Allow the given interrupt to be enabled next time we enable irqs. */
188#define arch_local_irq_unmask(interrupt) \
189	this_cpu_or(interrupts_enabled_mask, (1ULL << (interrupt)))
190
191/* Allow the given interrupt to be enabled immediately, if !irqs_disabled. */
192#define arch_local_irq_unmask_now(interrupt) do { \
193	arch_local_irq_unmask(interrupt); \
194	if (!irqs_disabled()) \
195		interrupt_mask_reset(interrupt); \
196} while (0)
197
198#else /* __ASSEMBLY__ */
199
200/* We provide a somewhat more restricted set for assembly. */
201
202#ifdef __tilegx__
203
204#if INT_MEM_ERROR != 0
205# error Fix IRQS_DISABLED() macro
206#endif
207
208/* Return 0 or 1 to indicate whether interrupts are currently disabled. */
209#define IRQS_DISABLED(tmp)					\
210	mfspr   tmp, SPR_INTERRUPT_MASK_K;			\
211	andi    tmp, tmp, 1
212
213/* Load up a pointer to &interrupts_enabled_mask. */
214#define GET_INTERRUPTS_ENABLED_MASK_PTR(reg)			\
215	moveli reg, hw2_last(interrupts_enabled_mask);		\
216	shl16insli reg, reg, hw1(interrupts_enabled_mask);	\
217	shl16insli reg, reg, hw0(interrupts_enabled_mask);	\
218	add     reg, reg, tp
219
220/* Disable interrupts. */
221#define IRQ_DISABLE(tmp0, tmp1)					\
222	moveli  tmp0, hw2_last(LINUX_MASKABLE_INTERRUPTS);	\
223	shl16insli tmp0, tmp0, hw1(LINUX_MASKABLE_INTERRUPTS);	\
224	shl16insli tmp0, tmp0, hw0(LINUX_MASKABLE_INTERRUPTS);	\
225	mtspr   SPR_INTERRUPT_MASK_SET_K, tmp0
226
227/* Disable ALL synchronous interrupts (used by NMI entry). */
228#define IRQ_DISABLE_ALL(tmp)					\
229	movei   tmp, -1;					\
230	mtspr   SPR_INTERRUPT_MASK_SET_K, tmp
231
232/* Enable interrupts. */
233#define IRQ_ENABLE_LOAD(tmp0, tmp1)				\
234	GET_INTERRUPTS_ENABLED_MASK_PTR(tmp0);			\
235	ld      tmp0, tmp0
236#define IRQ_ENABLE_APPLY(tmp0, tmp1)				\
237	mtspr   SPR_INTERRUPT_MASK_RESET_K, tmp0
238
239#else /* !__tilegx__ */
240
241/*
242 * Return 0 or 1 to indicate whether interrupts are currently disabled.
243 * Note that it's important that we use a bit from the "low" mask word,
244 * since when we are enabling, that is the word we write first, so if we
245 * are interrupted after only writing half of the mask, the interrupt
246 * handler will correctly observe that we have interrupts enabled, and
247 * will enable interrupts itself on return from the interrupt handler
248 * (making the original code's write of the "high" mask word idempotent).
249 */
250#define IRQS_DISABLED(tmp)					\
251	mfspr   tmp, SPR_INTERRUPT_MASK_K_0;			\
252	shri    tmp, tmp, INT_MEM_ERROR;			\
253	andi    tmp, tmp, 1
254
255/* Load up a pointer to &interrupts_enabled_mask. */
256#define GET_INTERRUPTS_ENABLED_MASK_PTR(reg)			\
257	moveli  reg, lo16(interrupts_enabled_mask);		\
258	auli    reg, reg, ha16(interrupts_enabled_mask);	\
259	add     reg, reg, tp
260
261/* Disable interrupts. */
262#define IRQ_DISABLE(tmp0, tmp1)					\
263	{							\
264	 movei  tmp0, LINUX_MASKABLE_INTERRUPTS_LO;		\
265	 moveli tmp1, lo16(LINUX_MASKABLE_INTERRUPTS_HI)	\
266	};							\
267	{							\
268	 mtspr  SPR_INTERRUPT_MASK_SET_K_0, tmp0;		\
269	 auli   tmp1, tmp1, ha16(LINUX_MASKABLE_INTERRUPTS_HI)	\
270	};							\
271	mtspr   SPR_INTERRUPT_MASK_SET_K_1, tmp1
272
273/* Disable ALL synchronous interrupts (used by NMI entry). */
274#define IRQ_DISABLE_ALL(tmp)					\
275	movei   tmp, -1;					\
276	mtspr   SPR_INTERRUPT_MASK_SET_K_0, tmp;		\
277	mtspr   SPR_INTERRUPT_MASK_SET_K_1, tmp
278
279/* Enable interrupts. */
280#define IRQ_ENABLE_LOAD(tmp0, tmp1)				\
281	GET_INTERRUPTS_ENABLED_MASK_PTR(tmp0);			\
282	{							\
283	 lw     tmp0, tmp0;					\
284	 addi   tmp1, tmp0, 4					\
285	};							\
286	lw      tmp1, tmp1
287#define IRQ_ENABLE_APPLY(tmp0, tmp1)				\
288	mtspr   SPR_INTERRUPT_MASK_RESET_K_0, tmp0;		\
289	mtspr   SPR_INTERRUPT_MASK_RESET_K_1, tmp1
290#endif
291
292#define IRQ_ENABLE(tmp0, tmp1)					\
293	IRQ_ENABLE_LOAD(tmp0, tmp1);				\
294	IRQ_ENABLE_APPLY(tmp0, tmp1)
295
296/*
297 * Do the CPU's IRQ-state tracing from assembly code. We call a
298 * C function, but almost everywhere we do, we don't mind clobbering
299 * all the caller-saved registers.
300 */
301#ifdef CONFIG_TRACE_IRQFLAGS
302# define TRACE_IRQS_ON  jal trace_hardirqs_on
303# define TRACE_IRQS_OFF jal trace_hardirqs_off
304#else
305# define TRACE_IRQS_ON
306# define TRACE_IRQS_OFF
307#endif
308
309#endif /* __ASSEMBLY__ */
310
311#endif /* _ASM_TILE_IRQFLAGS_H */
312