1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 2008 Ralf Baechle (ralf@linux-mips.org)
7 * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved.
8 */
9 #include <linux/bitmap.h>
10 #include <linux/init.h>
11 #include <linux/smp.h>
12 #include <linux/irq.h>
13 #include <linux/clocksource.h>
14
15 #include <asm/io.h>
16 #include <asm/gic.h>
17 #include <asm/setup.h>
18 #include <asm/traps.h>
19 #include <linux/hardirq.h>
20 #include <asm-generic/bitops/find.h>
21
22 unsigned int gic_frequency;
23 unsigned int gic_present;
24 unsigned long _gic_base;
25 unsigned int gic_irq_base;
26 unsigned int gic_irq_flags[GIC_NUM_INTRS];
27
28 /* The index into this array is the vector # of the interrupt. */
29 struct gic_shared_intr_map gic_shared_intr_map[GIC_NUM_INTRS];
30
31 struct gic_pcpu_mask {
32 DECLARE_BITMAP(pcpu_mask, GIC_NUM_INTRS);
33 };
34
35 struct gic_pending_regs {
36 DECLARE_BITMAP(pending, GIC_NUM_INTRS);
37 };
38
39 struct gic_intrmask_regs {
40 DECLARE_BITMAP(intrmask, GIC_NUM_INTRS);
41 };
42
43 static struct gic_pcpu_mask pcpu_masks[NR_CPUS];
44 static struct gic_pending_regs pending_regs[NR_CPUS];
45 static struct gic_intrmask_regs intrmask_regs[NR_CPUS];
46
47 #if defined(CONFIG_CSRC_GIC) || defined(CONFIG_CEVT_GIC)
gic_read_count(void)48 cycle_t gic_read_count(void)
49 {
50 unsigned int hi, hi2, lo;
51
52 do {
53 GICREAD(GIC_REG(SHARED, GIC_SH_COUNTER_63_32), hi);
54 GICREAD(GIC_REG(SHARED, GIC_SH_COUNTER_31_00), lo);
55 GICREAD(GIC_REG(SHARED, GIC_SH_COUNTER_63_32), hi2);
56 } while (hi2 != hi);
57
58 return (((cycle_t) hi) << 32) + lo;
59 }
60
gic_write_compare(cycle_t cnt)61 void gic_write_compare(cycle_t cnt)
62 {
63 GICWRITE(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_HI),
64 (int)(cnt >> 32));
65 GICWRITE(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_LO),
66 (int)(cnt & 0xffffffff));
67 }
68
gic_write_cpu_compare(cycle_t cnt,int cpu)69 void gic_write_cpu_compare(cycle_t cnt, int cpu)
70 {
71 unsigned long flags;
72
73 local_irq_save(flags);
74
75 GICWRITE(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR), cpu);
76 GICWRITE(GIC_REG(VPE_OTHER, GIC_VPE_COMPARE_HI),
77 (int)(cnt >> 32));
78 GICWRITE(GIC_REG(VPE_OTHER, GIC_VPE_COMPARE_LO),
79 (int)(cnt & 0xffffffff));
80
81 local_irq_restore(flags);
82 }
83
gic_read_compare(void)84 cycle_t gic_read_compare(void)
85 {
86 unsigned int hi, lo;
87
88 GICREAD(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_HI), hi);
89 GICREAD(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_LO), lo);
90
91 return (((cycle_t) hi) << 32) + lo;
92 }
93 #endif
94
gic_get_timer_pending(void)95 unsigned int gic_get_timer_pending(void)
96 {
97 unsigned int vpe_pending;
98
99 GICWRITE(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR), 0);
100 GICREAD(GIC_REG(VPE_OTHER, GIC_VPE_PEND), vpe_pending);
101 return (vpe_pending & GIC_VPE_PEND_TIMER_MSK);
102 }
103
gic_bind_eic_interrupt(int irq,int set)104 void gic_bind_eic_interrupt(int irq, int set)
105 {
106 /* Convert irq vector # to hw int # */
107 irq -= GIC_PIN_TO_VEC_OFFSET;
108
109 /* Set irq to use shadow set */
110 GICWRITE(GIC_REG_ADDR(VPE_LOCAL, GIC_VPE_EIC_SS(irq)), set);
111 }
112
gic_send_ipi(unsigned int intr)113 void gic_send_ipi(unsigned int intr)
114 {
115 GICWRITE(GIC_REG(SHARED, GIC_SH_WEDGE), 0x80000000 | intr);
116 }
117
gic_eic_irq_dispatch(void)118 static void gic_eic_irq_dispatch(void)
119 {
120 unsigned int cause = read_c0_cause();
121 int irq;
122
123 irq = (cause & ST0_IM) >> STATUSB_IP2;
124 if (irq == 0)
125 irq = -1;
126
127 if (irq >= 0)
128 do_IRQ(gic_irq_base + irq);
129 else
130 spurious_interrupt();
131 }
132
vpe_local_setup(unsigned int numvpes)133 static void __init vpe_local_setup(unsigned int numvpes)
134 {
135 unsigned long timer_intr = GIC_INT_TMR;
136 unsigned long perf_intr = GIC_INT_PERFCTR;
137 unsigned int vpe_ctl;
138 int i;
139
140 if (cpu_has_veic) {
141 /*
142 * GIC timer interrupt -> CPU HW Int X (vector X+2) ->
143 * map to pin X+2-1 (since GIC adds 1)
144 */
145 timer_intr += (GIC_CPU_TO_VEC_OFFSET - GIC_PIN_TO_VEC_OFFSET);
146 /*
147 * GIC perfcnt interrupt -> CPU HW Int X (vector X+2) ->
148 * map to pin X+2-1 (since GIC adds 1)
149 */
150 perf_intr += (GIC_CPU_TO_VEC_OFFSET - GIC_PIN_TO_VEC_OFFSET);
151 }
152
153 /*
154 * Setup the default performance counter timer interrupts
155 * for all VPEs
156 */
157 for (i = 0; i < numvpes; i++) {
158 GICWRITE(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR), i);
159
160 /* Are Interrupts locally routable? */
161 GICREAD(GIC_REG(VPE_OTHER, GIC_VPE_CTL), vpe_ctl);
162 if (vpe_ctl & GIC_VPE_CTL_TIMER_RTBL_MSK)
163 GICWRITE(GIC_REG(VPE_OTHER, GIC_VPE_TIMER_MAP),
164 GIC_MAP_TO_PIN_MSK | timer_intr);
165 if (cpu_has_veic) {
166 set_vi_handler(timer_intr + GIC_PIN_TO_VEC_OFFSET,
167 gic_eic_irq_dispatch);
168 gic_shared_intr_map[timer_intr + GIC_PIN_TO_VEC_OFFSET].local_intr_mask |= GIC_VPE_RMASK_TIMER_MSK;
169 }
170
171 if (vpe_ctl & GIC_VPE_CTL_PERFCNT_RTBL_MSK)
172 GICWRITE(GIC_REG(VPE_OTHER, GIC_VPE_PERFCTR_MAP),
173 GIC_MAP_TO_PIN_MSK | perf_intr);
174 if (cpu_has_veic) {
175 set_vi_handler(perf_intr + GIC_PIN_TO_VEC_OFFSET, gic_eic_irq_dispatch);
176 gic_shared_intr_map[perf_intr + GIC_PIN_TO_VEC_OFFSET].local_intr_mask |= GIC_VPE_RMASK_PERFCNT_MSK;
177 }
178 }
179 }
180
gic_compare_int(void)181 unsigned int gic_compare_int(void)
182 {
183 unsigned int pending;
184
185 GICREAD(GIC_REG(VPE_LOCAL, GIC_VPE_PEND), pending);
186 if (pending & GIC_VPE_PEND_CMP_MSK)
187 return 1;
188 else
189 return 0;
190 }
191
gic_get_int_mask(unsigned long * dst,const unsigned long * src)192 void gic_get_int_mask(unsigned long *dst, const unsigned long *src)
193 {
194 unsigned int i;
195 unsigned long *pending, *intrmask, *pcpu_mask;
196 unsigned long *pending_abs, *intrmask_abs;
197
198 /* Get per-cpu bitmaps */
199 pending = pending_regs[smp_processor_id()].pending;
200 intrmask = intrmask_regs[smp_processor_id()].intrmask;
201 pcpu_mask = pcpu_masks[smp_processor_id()].pcpu_mask;
202
203 pending_abs = (unsigned long *) GIC_REG_ABS_ADDR(SHARED,
204 GIC_SH_PEND_31_0_OFS);
205 intrmask_abs = (unsigned long *) GIC_REG_ABS_ADDR(SHARED,
206 GIC_SH_MASK_31_0_OFS);
207
208 for (i = 0; i < BITS_TO_LONGS(GIC_NUM_INTRS); i++) {
209 GICREAD(*pending_abs, pending[i]);
210 GICREAD(*intrmask_abs, intrmask[i]);
211 pending_abs++;
212 intrmask_abs++;
213 }
214
215 bitmap_and(pending, pending, intrmask, GIC_NUM_INTRS);
216 bitmap_and(pending, pending, pcpu_mask, GIC_NUM_INTRS);
217 bitmap_and(dst, src, pending, GIC_NUM_INTRS);
218 }
219
gic_get_int(void)220 unsigned int gic_get_int(void)
221 {
222 DECLARE_BITMAP(interrupts, GIC_NUM_INTRS);
223
224 bitmap_fill(interrupts, GIC_NUM_INTRS);
225 gic_get_int_mask(interrupts, interrupts);
226
227 return find_first_bit(interrupts, GIC_NUM_INTRS);
228 }
229
gic_mask_irq(struct irq_data * d)230 static void gic_mask_irq(struct irq_data *d)
231 {
232 GIC_CLR_INTR_MASK(d->irq - gic_irq_base);
233 }
234
gic_unmask_irq(struct irq_data * d)235 static void gic_unmask_irq(struct irq_data *d)
236 {
237 GIC_SET_INTR_MASK(d->irq - gic_irq_base);
238 }
239
240 #ifdef CONFIG_SMP
241 static DEFINE_SPINLOCK(gic_lock);
242
gic_set_affinity(struct irq_data * d,const struct cpumask * cpumask,bool force)243 static int gic_set_affinity(struct irq_data *d, const struct cpumask *cpumask,
244 bool force)
245 {
246 unsigned int irq = (d->irq - gic_irq_base);
247 cpumask_t tmp = CPU_MASK_NONE;
248 unsigned long flags;
249 int i;
250
251 cpumask_and(&tmp, cpumask, cpu_online_mask);
252 if (cpus_empty(tmp))
253 return -1;
254
255 /* Assumption : cpumask refers to a single CPU */
256 spin_lock_irqsave(&gic_lock, flags);
257
258 /* Re-route this IRQ */
259 GIC_SH_MAP_TO_VPE_SMASK(irq, first_cpu(tmp));
260
261 /* Update the pcpu_masks */
262 for (i = 0; i < NR_CPUS; i++)
263 clear_bit(irq, pcpu_masks[i].pcpu_mask);
264 set_bit(irq, pcpu_masks[first_cpu(tmp)].pcpu_mask);
265
266 cpumask_copy(d->affinity, cpumask);
267 spin_unlock_irqrestore(&gic_lock, flags);
268
269 return IRQ_SET_MASK_OK_NOCOPY;
270 }
271 #endif
272
273 static struct irq_chip gic_irq_controller = {
274 .name = "MIPS GIC",
275 .irq_ack = gic_irq_ack,
276 .irq_mask = gic_mask_irq,
277 .irq_mask_ack = gic_mask_irq,
278 .irq_unmask = gic_unmask_irq,
279 .irq_eoi = gic_finish_irq,
280 #ifdef CONFIG_SMP
281 .irq_set_affinity = gic_set_affinity,
282 #endif
283 };
284
gic_setup_intr(unsigned int intr,unsigned int cpu,unsigned int pin,unsigned int polarity,unsigned int trigtype,unsigned int flags)285 static void __init gic_setup_intr(unsigned int intr, unsigned int cpu,
286 unsigned int pin, unsigned int polarity, unsigned int trigtype,
287 unsigned int flags)
288 {
289 struct gic_shared_intr_map *map_ptr;
290
291 /* Setup Intr to Pin mapping */
292 if (pin & GIC_MAP_TO_NMI_MSK) {
293 int i;
294
295 GICWRITE(GIC_REG_ADDR(SHARED, GIC_SH_MAP_TO_PIN(intr)), pin);
296 /* FIXME: hack to route NMI to all cpu's */
297 for (i = 0; i < NR_CPUS; i += 32) {
298 GICWRITE(GIC_REG_ADDR(SHARED,
299 GIC_SH_MAP_TO_VPE_REG_OFF(intr, i)),
300 0xffffffff);
301 }
302 } else {
303 GICWRITE(GIC_REG_ADDR(SHARED, GIC_SH_MAP_TO_PIN(intr)),
304 GIC_MAP_TO_PIN_MSK | pin);
305 /* Setup Intr to CPU mapping */
306 GIC_SH_MAP_TO_VPE_SMASK(intr, cpu);
307 if (cpu_has_veic) {
308 set_vi_handler(pin + GIC_PIN_TO_VEC_OFFSET,
309 gic_eic_irq_dispatch);
310 map_ptr = &gic_shared_intr_map[pin + GIC_PIN_TO_VEC_OFFSET];
311 if (map_ptr->num_shared_intr >= GIC_MAX_SHARED_INTR)
312 BUG();
313 map_ptr->intr_list[map_ptr->num_shared_intr++] = intr;
314 }
315 }
316
317 /* Setup Intr Polarity */
318 GIC_SET_POLARITY(intr, polarity);
319
320 /* Setup Intr Trigger Type */
321 GIC_SET_TRIGGER(intr, trigtype);
322
323 /* Init Intr Masks */
324 GIC_CLR_INTR_MASK(intr);
325
326 /* Initialise per-cpu Interrupt software masks */
327 set_bit(intr, pcpu_masks[cpu].pcpu_mask);
328
329 if ((flags & GIC_FLAG_TRANSPARENT) && (cpu_has_veic == 0))
330 GIC_SET_INTR_MASK(intr);
331 if (trigtype == GIC_TRIG_EDGE)
332 gic_irq_flags[intr] |= GIC_TRIG_EDGE;
333 }
334
gic_basic_init(int numintrs,int numvpes,struct gic_intr_map * intrmap,int mapsize)335 static void __init gic_basic_init(int numintrs, int numvpes,
336 struct gic_intr_map *intrmap, int mapsize)
337 {
338 unsigned int i, cpu;
339 unsigned int pin_offset = 0;
340
341 board_bind_eic_interrupt = &gic_bind_eic_interrupt;
342
343 /* Setup defaults */
344 for (i = 0; i < numintrs; i++) {
345 GIC_SET_POLARITY(i, GIC_POL_POS);
346 GIC_SET_TRIGGER(i, GIC_TRIG_LEVEL);
347 GIC_CLR_INTR_MASK(i);
348 if (i < GIC_NUM_INTRS) {
349 gic_irq_flags[i] = 0;
350 gic_shared_intr_map[i].num_shared_intr = 0;
351 gic_shared_intr_map[i].local_intr_mask = 0;
352 }
353 }
354
355 /*
356 * In EIC mode, the HW_INT# is offset by (2-1). Need to subtract
357 * one because the GIC will add one (since 0=no intr).
358 */
359 if (cpu_has_veic)
360 pin_offset = (GIC_CPU_TO_VEC_OFFSET - GIC_PIN_TO_VEC_OFFSET);
361
362 /* Setup specifics */
363 for (i = 0; i < mapsize; i++) {
364 cpu = intrmap[i].cpunum;
365 if (cpu == GIC_UNUSED)
366 continue;
367 gic_setup_intr(i,
368 intrmap[i].cpunum,
369 intrmap[i].pin + pin_offset,
370 intrmap[i].polarity,
371 intrmap[i].trigtype,
372 intrmap[i].flags);
373 }
374
375 vpe_local_setup(numvpes);
376 }
377
gic_init(unsigned long gic_base_addr,unsigned long gic_addrspace_size,struct gic_intr_map * intr_map,unsigned int intr_map_size,unsigned int irqbase)378 void __init gic_init(unsigned long gic_base_addr,
379 unsigned long gic_addrspace_size,
380 struct gic_intr_map *intr_map, unsigned int intr_map_size,
381 unsigned int irqbase)
382 {
383 unsigned int gicconfig;
384 int numvpes, numintrs;
385
386 _gic_base = (unsigned long) ioremap_nocache(gic_base_addr,
387 gic_addrspace_size);
388 gic_irq_base = irqbase;
389
390 GICREAD(GIC_REG(SHARED, GIC_SH_CONFIG), gicconfig);
391 numintrs = (gicconfig & GIC_SH_CONFIG_NUMINTRS_MSK) >>
392 GIC_SH_CONFIG_NUMINTRS_SHF;
393 numintrs = ((numintrs + 1) * 8);
394
395 numvpes = (gicconfig & GIC_SH_CONFIG_NUMVPES_MSK) >>
396 GIC_SH_CONFIG_NUMVPES_SHF;
397 numvpes = numvpes + 1;
398
399 gic_basic_init(numintrs, numvpes, intr_map, intr_map_size);
400
401 gic_platform_init(numintrs, &gic_irq_controller);
402 }
403