xref: /optee_os/core/drivers/gic.c (revision c2f5808039471d8cb9ac43385b63fb8dc6aa8ac4)
1 /*
2  * Copyright (c) 2016, Linaro Limited
3  * Copyright (c) 2014, STMicroelectronics International N.V.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright notice,
10  * this list of conditions and the following disclaimer.
11  *
12  * 2. Redistributions in binary form must reproduce the above copyright notice,
13  * this list of conditions and the following disclaimer in the documentation
14  * and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <drivers/gic.h>
30 #include <kernel/interrupt.h>
31 #include <util.h>
32 #include <io.h>
33 #include <trace.h>
34 
35 #include <assert.h>
36 
37 /* Offsets from gic.gicc_base */
38 #define GICC_CTLR		(0x000)
39 #define GICC_PMR		(0x004)
40 #define GICC_IAR		(0x00C)
41 #define GICC_EOIR		(0x010)
42 
43 #define GICC_CTLR_ENABLEGRP0	(1 << 0)
44 #define GICC_CTLR_ENABLEGRP1	(1 << 1)
45 #define GICC_CTLR_FIQEN		(1 << 3)
46 
47 /* Offsets from gic.gicd_base */
48 #define GICD_CTLR		(0x000)
49 #define GICD_TYPER		(0x004)
50 #define GICD_IGROUPR(n)		(0x080 + (n) * 4)
51 #define GICD_ISENABLER(n)	(0x100 + (n) * 4)
52 #define GICD_ICENABLER(n)	(0x180 + (n) * 4)
53 #define GICD_ICPENDR(n)		(0x280 + (n) * 4)
54 #define GICD_IPRIORITYR(n)	(0x400 + (n) * 4)
55 #define GICD_ITARGETSR(n)	(0x800 + (n) * 4)
56 
57 #define GICD_CTLR_ENABLEGRP0	(1 << 0)
58 #define GICD_CTLR_ENABLEGRP1	(1 << 1)
59 
60 /* Number of Private Peripheral Interrupt */
61 #define NUM_PPI	32
62 
63 /* Number of interrupts in one register */
64 #define NUM_INTS_PER_REG	32
65 
66 /* Number of targets in one register */
67 #define NUM_TARGETS_PER_REG	4
68 
69 /* Accessors to access ITARGETSRn */
70 #define ITARGETSR_FIELD_BITS	8
71 #define ITARGETSR_FIELD_MASK	0xff
72 
73 /* Maximum number of interrups a GIC can support */
74 #define GIC_MAX_INTS		1020
75 
76 #define GIC_SPURIOUS_ID		1023
77 
78 #define GICC_IAR_IT_ID_MASK	0x3ff
79 #define GICC_IAR_CPU_ID_MASK	0x7
80 #define GICC_IAR_CPU_ID_SHIFT	10
81 
82 static void gic_op_add(struct itr_chip *chip, size_t it, uint32_t flags);
83 static void gic_op_enable(struct itr_chip *chip, size_t it);
84 static void gic_op_disable(struct itr_chip *chip, size_t it);
85 
86 static const struct itr_ops gic_ops = {
87 	.add = gic_op_add,
88 	.enable = gic_op_enable,
89 	.disable = gic_op_disable,
90 };
91 
92 static size_t probe_max_it(vaddr_t gicc_base, vaddr_t gicd_base)
93 {
94 	int i;
95 	uint32_t old_ctlr;
96 	size_t ret = 0;
97 	const size_t max_regs = ((GIC_MAX_INTS + NUM_INTS_PER_REG - 1) /
98 					NUM_INTS_PER_REG) - 1;
99 
100 	/*
101 	 * Probe which interrupt number is the largest.
102 	 */
103 	old_ctlr = read32(gicc_base + GICC_CTLR);
104 	write32(0, gicc_base + GICC_CTLR);
105 	for (i = max_regs; i >= 0; i--) {
106 		uint32_t old_reg;
107 		uint32_t reg;
108 		int b;
109 
110 		old_reg = read32(gicd_base + GICD_ISENABLER(i));
111 		write32(0xffffffff, gicd_base + GICD_ISENABLER(i));
112 		reg = read32(gicd_base + GICD_ISENABLER(i));
113 		write32(old_reg, gicd_base + GICD_ICENABLER(i));
114 		for (b = NUM_INTS_PER_REG - 1; b >= 0; b--) {
115 			if (BIT32(b) & reg) {
116 				ret = i * NUM_INTS_PER_REG + b;
117 				goto out;
118 			}
119 		}
120 	}
121 out:
122 	write32(old_ctlr, gicc_base + GICC_CTLR);
123 	return ret;
124 }
125 
126 void gic_cpu_init(struct gic_data *gd)
127 {
128 	/* per-CPU interrupts config:
129 	 * ID0-ID7(SGI)   for Non-secure interrupts
130 	 * ID8-ID15(SGI)  for Secure interrupts.
131 	 * All PPI config as Non-secure interrupts.
132 	 */
133 	write32(0xffff00ff, gd->gicd_base + GICD_IGROUPR(0));
134 
135 	/* Set the priority mask to permit Non-secure interrupts, and to
136 	 * allow the Non-secure world to adjust the priority mask itself
137 	 */
138 	write32(0x80, gd->gicc_base + GICC_PMR);
139 
140 	/* Enable GIC */
141 	write32(GICC_CTLR_ENABLEGRP0 | GICC_CTLR_ENABLEGRP1 | GICC_CTLR_FIQEN,
142 		gd->gicc_base + GICC_CTLR);
143 }
144 
145 void gic_init(struct gic_data *gd, vaddr_t gicc_base, vaddr_t gicd_base)
146 {
147 	size_t n;
148 
149 	gic_init_base_addr(gd, gicc_base, gicd_base);
150 
151 	for (n = 0; n <= gd->max_it / NUM_INTS_PER_REG; n++) {
152 		/* Disable interrupts */
153 		write32(0xffffffff, gd->gicd_base + GICD_ICENABLER(n));
154 
155 		/* Make interrupts non-pending */
156 		write32(0xffffffff, gd->gicd_base + GICD_ICPENDR(n));
157 
158 		/* Mark interrupts non-secure */
159 		if (n == 0) {
160 			/* per-CPU inerrupts config:
161                          * ID0-ID7(SGI)   for Non-secure interrupts
162                          * ID8-ID15(SGI)  for Secure interrupts.
163                          * All PPI config as Non-secure interrupts.
164 			 */
165 			write32(0xffff00ff, gd->gicd_base + GICD_IGROUPR(n));
166 		} else {
167 			write32(0xffffffff, gd->gicd_base + GICD_IGROUPR(n));
168 		}
169 	}
170 
171 	/* Set the priority mask to permit Non-secure interrupts, and to
172 	 * allow the Non-secure world to adjust the priority mask itself
173 	 */
174 	write32(0x80, gd->gicc_base + GICC_PMR);
175 
176 	/* Enable GIC */
177 	write32(GICC_CTLR_ENABLEGRP0 | GICC_CTLR_ENABLEGRP1 | GICC_CTLR_FIQEN,
178 		gd->gicc_base + GICC_CTLR);
179 	write32(GICD_CTLR_ENABLEGRP0 | GICD_CTLR_ENABLEGRP1,
180 		gd->gicd_base + GICD_CTLR);
181 }
182 
183 void gic_init_base_addr(struct gic_data *gd, vaddr_t gicc_base,
184 			vaddr_t gicd_base)
185 {
186 	gd->gicc_base = gicc_base;
187 	gd->gicd_base = gicd_base;
188 	gd->max_it = probe_max_it(gicc_base, gicd_base);
189 	gd->chip.ops = &gic_ops;
190 }
191 
192 static void gic_it_add(struct gic_data *gd, size_t it)
193 {
194 	size_t idx = it / NUM_INTS_PER_REG;
195 	uint32_t mask = 1 << (it % NUM_INTS_PER_REG);
196 
197 	assert(it <= gd->max_it); /* Not too large */
198 
199 	/* Disable the interrupt */
200 	write32(mask, gd->gicd_base + GICD_ICENABLER(idx));
201 	/* Make it non-pending */
202 	write32(mask, gd->gicd_base + GICD_ICPENDR(idx));
203 	/* Assign it to group0 */
204 	write32(read32(gd->gicd_base + GICD_IGROUPR(idx)) & ~mask,
205 			gd->gicd_base + GICD_IGROUPR(idx));
206 }
207 
208 static void gic_it_set_cpu_mask(struct gic_data *gd, size_t it,
209 				uint8_t cpu_mask)
210 {
211 	size_t idx = it / NUM_INTS_PER_REG;
212 	uint32_t mask = 1 << (it % NUM_INTS_PER_REG);
213 	uint32_t target, target_shift;
214 
215 	assert(it <= gd->max_it); /* Not too large */
216 	/* Assigned to group0 */
217 	assert(!(read32(gd->gicd_base + GICD_IGROUPR(idx)) & mask));
218 
219 	/* Route it to selected CPUs */
220 	target = read32(gd->gicd_base +
221 			GICD_ITARGETSR(it / NUM_TARGETS_PER_REG));
222 	target_shift = (it % NUM_TARGETS_PER_REG) * ITARGETSR_FIELD_BITS;
223 	target &= ~(ITARGETSR_FIELD_MASK << target_shift);
224 	target |= cpu_mask << target_shift;
225 	DMSG("cpu_mask: writing 0x%x to 0x%" PRIxVA,
226 	     target, gd->gicd_base + GICD_ITARGETSR(it / NUM_TARGETS_PER_REG));
227 	write32(target,
228 		gd->gicd_base + GICD_ITARGETSR(it / NUM_TARGETS_PER_REG));
229 	DMSG("cpu_mask: 0x%x\n",
230 	     read32(gd->gicd_base + GICD_ITARGETSR(it / NUM_TARGETS_PER_REG)));
231 }
232 
233 static void gic_it_set_prio(struct gic_data *gd, size_t it, uint8_t prio)
234 {
235 	size_t idx = it / NUM_INTS_PER_REG;
236 	uint32_t mask = 1 << (it % NUM_INTS_PER_REG);
237 
238 	assert(it <= gd->max_it); /* Not too large */
239 	/* Assigned to group0 */
240 	assert(!(read32(gd->gicd_base + GICD_IGROUPR(idx)) & mask));
241 
242 	/* Set prio it to selected CPUs */
243 	DMSG("prio: writing 0x%x to 0x%" PRIxVA,
244 		prio, gd->gicd_base + GICD_IPRIORITYR(0) + it);
245 	write8(prio, gd->gicd_base + GICD_IPRIORITYR(0) + it);
246 }
247 
248 static void gic_it_enable(struct gic_data *gd, size_t it)
249 {
250 	size_t idx = it / NUM_INTS_PER_REG;
251 	uint32_t mask = 1 << (it % NUM_INTS_PER_REG);
252 
253 	assert(it <= gd->max_it); /* Not too large */
254 	/* Assigned to group0 */
255 	assert(!(read32(gd->gicd_base + GICD_IGROUPR(idx)) & mask));
256 	/* Not enabled yet */
257 	assert(!(read32(gd->gicd_base + GICD_ISENABLER(idx)) & mask));
258 
259 	/* Enable the interrupt */
260 	write32(mask, gd->gicd_base + GICD_ISENABLER(idx));
261 }
262 
263 static void gic_it_disable(struct gic_data *gd, size_t it)
264 {
265 	size_t idx = it / NUM_INTS_PER_REG;
266 	uint32_t mask = 1 << (it % NUM_INTS_PER_REG);
267 
268 	assert(it <= gd->max_it); /* Not too large */
269 	/* Assigned to group0 */
270 	assert(!(read32(gd->gicd_base + GICD_IGROUPR(idx)) & mask));
271 
272 	/* Disable the interrupt */
273 	write32(mask, gd->gicd_base + GICD_ICENABLER(idx));
274 }
275 
276 static uint32_t gic_read_iar(struct gic_data *gd)
277 {
278 	return read32(gd->gicc_base + GICC_IAR);
279 }
280 
281 static void gic_write_eoir(struct gic_data *gd, uint32_t eoir)
282 {
283 	write32(eoir, gd->gicc_base + GICC_EOIR);
284 }
285 
286 static bool gic_it_is_enabled(struct gic_data *gd, size_t it)
287 {
288 	size_t idx = it / NUM_INTS_PER_REG;
289 	uint32_t mask = 1 << (it % NUM_INTS_PER_REG);
290 	return !!(read32(gd->gicd_base + GICD_ISENABLER(idx)) & mask);
291 }
292 
293 static bool __maybe_unused gic_it_get_group(struct gic_data *gd, size_t it)
294 {
295 	size_t idx = it / NUM_INTS_PER_REG;
296 	uint32_t mask = 1 << (it % NUM_INTS_PER_REG);
297 	return !!(read32(gd->gicd_base + GICD_IGROUPR(idx)) & mask);
298 }
299 
300 static uint32_t __maybe_unused gic_it_get_target(struct gic_data *gd, size_t it)
301 {
302 	size_t reg_idx = it / NUM_TARGETS_PER_REG;
303 	uint32_t target_shift = (it % NUM_TARGETS_PER_REG) *
304 				ITARGETSR_FIELD_BITS;
305 	uint32_t target_mask = ITARGETSR_FIELD_MASK << target_shift;
306 	uint32_t target =
307 		read32(gd->gicd_base + GICD_ITARGETSR(reg_idx)) & target_mask;
308 
309 	target = target >> target_shift;
310 	return target;
311 }
312 
313 void gic_dump_state(struct gic_data *gd)
314 {
315 	int i;
316 
317 	DMSG("GICC_CTLR: 0x%x", read32(gd->gicc_base + GICC_CTLR));
318 	DMSG("GICD_CTLR: 0x%x", read32(gd->gicd_base + GICD_CTLR));
319 
320 	for (i = 0; i < (int)gd->max_it; i++) {
321 		if (gic_it_is_enabled(gd, i)) {
322 			DMSG("irq%d: enabled, group:%d, target:%x", i,
323 			     gic_it_get_group(gd, i), gic_it_get_target(gd, i));
324 		}
325 	}
326 }
327 
328 void gic_it_handle(struct gic_data *gd)
329 {
330 	uint32_t iar;
331 	uint32_t id;
332 
333 	iar = gic_read_iar(gd);
334 	id = iar & GICC_IAR_IT_ID_MASK;
335 
336 	if (id == GIC_SPURIOUS_ID)
337 		DMSG("ignoring spurious interrupt");
338 	else
339 		itr_handle(id);
340 
341 	gic_write_eoir(gd, iar);
342 }
343 
344 static void gic_op_add(struct itr_chip *chip, size_t it,
345 		       uint32_t flags __unused)
346 {
347 	struct gic_data *gd = container_of(chip, struct gic_data, chip);
348 
349 	gic_it_add(gd, it);
350 	/* Set the CPU mask to deliver interrupts to any online core */
351 	gic_it_set_cpu_mask(gd, it, 0xff);
352 	gic_it_set_prio(gd, it, 0x1);
353 }
354 
355 static void gic_op_enable(struct itr_chip *chip, size_t it)
356 {
357 	struct gic_data *gd = container_of(chip, struct gic_data, chip);
358 
359 	gic_it_enable(gd, it);
360 }
361 
362 static void gic_op_disable(struct itr_chip *chip, size_t it)
363 {
364 	struct gic_data *gd = container_of(chip, struct gic_data, chip);
365 
366 	gic_it_disable(gd, it);
367 }
368