xref: /linux/tools/testing/selftests/kvm/lib/aarch64/gic_v3.c (revision 92815da4576a495cb6362cdfb132152fccc2222d)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ARM Generic Interrupt Controller (GIC) v3 support
4  */
5 
6 #include <linux/sizes.h>
7 
8 #include "kvm_util.h"
9 #include "processor.h"
10 #include "delay.h"
11 
12 #include "gic.h"
13 #include "gic_v3.h"
14 #include "gic_private.h"
15 
16 #define GICV3_MAX_CPUS			512
17 
18 #define GICD_INT_DEF_PRI		0xa0
19 #define GICD_INT_DEF_PRI_X4		((GICD_INT_DEF_PRI << 24) |\
20 					(GICD_INT_DEF_PRI << 16) |\
21 					(GICD_INT_DEF_PRI << 8) |\
22 					GICD_INT_DEF_PRI)
23 
24 #define ICC_PMR_DEF_PRIO		0xf0
25 
26 struct gicv3_data {
27 	unsigned int nr_cpus;
28 	unsigned int nr_spis;
29 };
30 
31 #define sgi_base_from_redist(redist_base)	(redist_base + SZ_64K)
32 #define DIST_BIT				(1U << 31)
33 
34 enum gicv3_intid_range {
35 	SGI_RANGE,
36 	PPI_RANGE,
37 	SPI_RANGE,
38 	INVALID_RANGE,
39 };
40 
41 static struct gicv3_data gicv3_data;
42 
43 static void gicv3_gicd_wait_for_rwp(void)
44 {
45 	unsigned int count = 100000; /* 1s */
46 
47 	while (readl(GICD_BASE_GVA + GICD_CTLR) & GICD_CTLR_RWP) {
48 		GUEST_ASSERT(count--);
49 		udelay(10);
50 	}
51 }
52 
53 static inline volatile void *gicr_base_cpu(uint32_t cpu)
54 {
55 	/* Align all the redistributors sequentially */
56 	return GICR_BASE_GVA + cpu * SZ_64K * 2;
57 }
58 
59 static void gicv3_gicr_wait_for_rwp(uint32_t cpu)
60 {
61 	unsigned int count = 100000; /* 1s */
62 
63 	while (readl(gicr_base_cpu(cpu) + GICR_CTLR) & GICR_CTLR_RWP) {
64 		GUEST_ASSERT(count--);
65 		udelay(10);
66 	}
67 }
68 
69 static void gicv3_wait_for_rwp(uint32_t cpu_or_dist)
70 {
71 	if (cpu_or_dist & DIST_BIT)
72 		gicv3_gicd_wait_for_rwp();
73 	else
74 		gicv3_gicr_wait_for_rwp(cpu_or_dist);
75 }
76 
77 static enum gicv3_intid_range get_intid_range(unsigned int intid)
78 {
79 	switch (intid) {
80 	case 0 ... 15:
81 		return SGI_RANGE;
82 	case 16 ... 31:
83 		return PPI_RANGE;
84 	case 32 ... 1019:
85 		return SPI_RANGE;
86 	}
87 
88 	/* We should not be reaching here */
89 	GUEST_ASSERT(0);
90 
91 	return INVALID_RANGE;
92 }
93 
94 static uint64_t gicv3_read_iar(void)
95 {
96 	uint64_t irqstat = read_sysreg_s(SYS_ICC_IAR1_EL1);
97 
98 	dsb(sy);
99 	return irqstat;
100 }
101 
102 static void gicv3_write_eoir(uint32_t irq)
103 {
104 	write_sysreg_s(irq, SYS_ICC_EOIR1_EL1);
105 	isb();
106 }
107 
108 static void gicv3_write_dir(uint32_t irq)
109 {
110 	write_sysreg_s(irq, SYS_ICC_DIR_EL1);
111 	isb();
112 }
113 
114 static void gicv3_set_priority_mask(uint64_t mask)
115 {
116 	write_sysreg_s(mask, SYS_ICC_PMR_EL1);
117 }
118 
119 static void gicv3_set_eoi_split(bool split)
120 {
121 	uint32_t val;
122 
123 	/*
124 	 * All other fields are read-only, so no need to read CTLR first. In
125 	 * fact, the kernel does the same.
126 	 */
127 	val = split ? (1U << 1) : 0;
128 	write_sysreg_s(val, SYS_ICC_CTLR_EL1);
129 	isb();
130 }
131 
132 uint32_t gicv3_reg_readl(uint32_t cpu_or_dist, uint64_t offset)
133 {
134 	volatile void *base = cpu_or_dist & DIST_BIT ? GICD_BASE_GVA
135 			: sgi_base_from_redist(gicr_base_cpu(cpu_or_dist));
136 	return readl(base + offset);
137 }
138 
139 void gicv3_reg_writel(uint32_t cpu_or_dist, uint64_t offset, uint32_t reg_val)
140 {
141 	volatile void *base = cpu_or_dist & DIST_BIT ? GICD_BASE_GVA
142 			: sgi_base_from_redist(gicr_base_cpu(cpu_or_dist));
143 	writel(reg_val, base + offset);
144 }
145 
146 uint32_t gicv3_getl_fields(uint32_t cpu_or_dist, uint64_t offset, uint32_t mask)
147 {
148 	return gicv3_reg_readl(cpu_or_dist, offset) & mask;
149 }
150 
151 void gicv3_setl_fields(uint32_t cpu_or_dist, uint64_t offset,
152 		uint32_t mask, uint32_t reg_val)
153 {
154 	uint32_t tmp = gicv3_reg_readl(cpu_or_dist, offset) & ~mask;
155 
156 	tmp |= (reg_val & mask);
157 	gicv3_reg_writel(cpu_or_dist, offset, tmp);
158 }
159 
160 /*
161  * We use a single offset for the distributor and redistributor maps as they
162  * have the same value in both. The only exceptions are registers that only
163  * exist in one and not the other, like GICR_WAKER that doesn't exist in the
164  * distributor map. Such registers are conveniently marked as reserved in the
165  * map that doesn't implement it; like GICR_WAKER's offset of 0x0014 being
166  * marked as "Reserved" in the Distributor map.
167  */
168 static void gicv3_access_reg(uint32_t intid, uint64_t offset,
169 		uint32_t reg_bits, uint32_t bits_per_field,
170 		bool write, uint32_t *val)
171 {
172 	uint32_t cpu = guest_get_vcpuid();
173 	enum gicv3_intid_range intid_range = get_intid_range(intid);
174 	uint32_t fields_per_reg, index, mask, shift;
175 	uint32_t cpu_or_dist;
176 
177 	GUEST_ASSERT(bits_per_field <= reg_bits);
178 	GUEST_ASSERT(!write || *val < (1U << bits_per_field));
179 	/*
180 	 * This function does not support 64 bit accesses. Just asserting here
181 	 * until we implement readq/writeq.
182 	 */
183 	GUEST_ASSERT(reg_bits == 32);
184 
185 	fields_per_reg = reg_bits / bits_per_field;
186 	index = intid % fields_per_reg;
187 	shift = index * bits_per_field;
188 	mask = ((1U << bits_per_field) - 1) << shift;
189 
190 	/* Set offset to the actual register holding intid's config. */
191 	offset += (intid / fields_per_reg) * (reg_bits / 8);
192 
193 	cpu_or_dist = (intid_range == SPI_RANGE) ? DIST_BIT : cpu;
194 
195 	if (write)
196 		gicv3_setl_fields(cpu_or_dist, offset, mask, *val << shift);
197 	*val = gicv3_getl_fields(cpu_or_dist, offset, mask) >> shift;
198 }
199 
200 static void gicv3_write_reg(uint32_t intid, uint64_t offset,
201 		uint32_t reg_bits, uint32_t bits_per_field, uint32_t val)
202 {
203 	gicv3_access_reg(intid, offset, reg_bits,
204 			bits_per_field, true, &val);
205 }
206 
207 static uint32_t gicv3_read_reg(uint32_t intid, uint64_t offset,
208 		uint32_t reg_bits, uint32_t bits_per_field)
209 {
210 	uint32_t val;
211 
212 	gicv3_access_reg(intid, offset, reg_bits,
213 			bits_per_field, false, &val);
214 	return val;
215 }
216 
217 static void gicv3_set_priority(uint32_t intid, uint32_t prio)
218 {
219 	gicv3_write_reg(intid, GICD_IPRIORITYR, 32, 8, prio);
220 }
221 
222 /* Sets the intid to be level-sensitive or edge-triggered. */
223 static void gicv3_irq_set_config(uint32_t intid, bool is_edge)
224 {
225 	uint32_t val;
226 
227 	/* N/A for private interrupts. */
228 	GUEST_ASSERT(get_intid_range(intid) == SPI_RANGE);
229 	val = is_edge ? 2 : 0;
230 	gicv3_write_reg(intid, GICD_ICFGR, 32, 2, val);
231 }
232 
233 static void gicv3_irq_enable(uint32_t intid)
234 {
235 	bool is_spi = get_intid_range(intid) == SPI_RANGE;
236 	uint32_t cpu = guest_get_vcpuid();
237 
238 	gicv3_write_reg(intid, GICD_ISENABLER, 32, 1, 1);
239 	gicv3_wait_for_rwp(is_spi ? DIST_BIT : cpu);
240 }
241 
242 static void gicv3_irq_disable(uint32_t intid)
243 {
244 	bool is_spi = get_intid_range(intid) == SPI_RANGE;
245 	uint32_t cpu = guest_get_vcpuid();
246 
247 	gicv3_write_reg(intid, GICD_ICENABLER, 32, 1, 1);
248 	gicv3_wait_for_rwp(is_spi ? DIST_BIT : cpu);
249 }
250 
251 static void gicv3_irq_set_active(uint32_t intid)
252 {
253 	gicv3_write_reg(intid, GICD_ISACTIVER, 32, 1, 1);
254 }
255 
256 static void gicv3_irq_clear_active(uint32_t intid)
257 {
258 	gicv3_write_reg(intid, GICD_ICACTIVER, 32, 1, 1);
259 }
260 
261 static bool gicv3_irq_get_active(uint32_t intid)
262 {
263 	return gicv3_read_reg(intid, GICD_ISACTIVER, 32, 1);
264 }
265 
266 static void gicv3_irq_set_pending(uint32_t intid)
267 {
268 	gicv3_write_reg(intid, GICD_ISPENDR, 32, 1, 1);
269 }
270 
271 static void gicv3_irq_clear_pending(uint32_t intid)
272 {
273 	gicv3_write_reg(intid, GICD_ICPENDR, 32, 1, 1);
274 }
275 
276 static bool gicv3_irq_get_pending(uint32_t intid)
277 {
278 	return gicv3_read_reg(intid, GICD_ISPENDR, 32, 1);
279 }
280 
281 static void gicv3_enable_redist(volatile void *redist_base)
282 {
283 	uint32_t val = readl(redist_base + GICR_WAKER);
284 	unsigned int count = 100000; /* 1s */
285 
286 	val &= ~GICR_WAKER_ProcessorSleep;
287 	writel(val, redist_base + GICR_WAKER);
288 
289 	/* Wait until the processor is 'active' */
290 	while (readl(redist_base + GICR_WAKER) & GICR_WAKER_ChildrenAsleep) {
291 		GUEST_ASSERT(count--);
292 		udelay(10);
293 	}
294 }
295 
296 static void gicv3_cpu_init(unsigned int cpu)
297 {
298 	volatile void *sgi_base;
299 	unsigned int i;
300 	volatile void *redist_base_cpu;
301 
302 	GUEST_ASSERT(cpu < gicv3_data.nr_cpus);
303 
304 	redist_base_cpu = gicr_base_cpu(cpu);
305 	sgi_base = sgi_base_from_redist(redist_base_cpu);
306 
307 	gicv3_enable_redist(redist_base_cpu);
308 
309 	/*
310 	 * Mark all the SGI and PPI interrupts as non-secure Group-1.
311 	 * Also, deactivate and disable them.
312 	 */
313 	writel(~0, sgi_base + GICR_IGROUPR0);
314 	writel(~0, sgi_base + GICR_ICACTIVER0);
315 	writel(~0, sgi_base + GICR_ICENABLER0);
316 
317 	/* Set a default priority for all the SGIs and PPIs */
318 	for (i = 0; i < 32; i += 4)
319 		writel(GICD_INT_DEF_PRI_X4,
320 				sgi_base + GICR_IPRIORITYR0 + i);
321 
322 	gicv3_gicr_wait_for_rwp(cpu);
323 
324 	/* Enable the GIC system register (ICC_*) access */
325 	write_sysreg_s(read_sysreg_s(SYS_ICC_SRE_EL1) | ICC_SRE_EL1_SRE,
326 			SYS_ICC_SRE_EL1);
327 
328 	/* Set a default priority threshold */
329 	write_sysreg_s(ICC_PMR_DEF_PRIO, SYS_ICC_PMR_EL1);
330 
331 	/* Enable non-secure Group-1 interrupts */
332 	write_sysreg_s(ICC_IGRPEN1_EL1_MASK, SYS_ICC_IGRPEN1_EL1);
333 }
334 
335 static void gicv3_dist_init(void)
336 {
337 	unsigned int i;
338 
339 	/* Disable the distributor until we set things up */
340 	writel(0, GICD_BASE_GVA + GICD_CTLR);
341 	gicv3_gicd_wait_for_rwp();
342 
343 	/*
344 	 * Mark all the SPI interrupts as non-secure Group-1.
345 	 * Also, deactivate and disable them.
346 	 */
347 	for (i = 32; i < gicv3_data.nr_spis; i += 32) {
348 		writel(~0, GICD_BASE_GVA + GICD_IGROUPR + i / 8);
349 		writel(~0, GICD_BASE_GVA + GICD_ICACTIVER + i / 8);
350 		writel(~0, GICD_BASE_GVA + GICD_ICENABLER + i / 8);
351 	}
352 
353 	/* Set a default priority for all the SPIs */
354 	for (i = 32; i < gicv3_data.nr_spis; i += 4)
355 		writel(GICD_INT_DEF_PRI_X4,
356 				GICD_BASE_GVA + GICD_IPRIORITYR + i);
357 
358 	/* Wait for the settings to sync-in */
359 	gicv3_gicd_wait_for_rwp();
360 
361 	/* Finally, enable the distributor globally with ARE */
362 	writel(GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G1A |
363 			GICD_CTLR_ENABLE_G1, GICD_BASE_GVA + GICD_CTLR);
364 	gicv3_gicd_wait_for_rwp();
365 }
366 
367 static void gicv3_init(unsigned int nr_cpus)
368 {
369 	GUEST_ASSERT(nr_cpus <= GICV3_MAX_CPUS);
370 
371 	gicv3_data.nr_cpus = nr_cpus;
372 	gicv3_data.nr_spis = GICD_TYPER_SPIS(
373 				readl(GICD_BASE_GVA + GICD_TYPER));
374 	if (gicv3_data.nr_spis > 1020)
375 		gicv3_data.nr_spis = 1020;
376 
377 	/*
378 	 * Initialize only the distributor for now.
379 	 * The redistributor and CPU interfaces are initialized
380 	 * later for every PE.
381 	 */
382 	gicv3_dist_init();
383 }
384 
385 const struct gic_common_ops gicv3_ops = {
386 	.gic_init = gicv3_init,
387 	.gic_cpu_init = gicv3_cpu_init,
388 	.gic_irq_enable = gicv3_irq_enable,
389 	.gic_irq_disable = gicv3_irq_disable,
390 	.gic_read_iar = gicv3_read_iar,
391 	.gic_write_eoir = gicv3_write_eoir,
392 	.gic_write_dir = gicv3_write_dir,
393 	.gic_set_priority_mask = gicv3_set_priority_mask,
394 	.gic_set_eoi_split = gicv3_set_eoi_split,
395 	.gic_set_priority = gicv3_set_priority,
396 	.gic_irq_set_active = gicv3_irq_set_active,
397 	.gic_irq_clear_active = gicv3_irq_clear_active,
398 	.gic_irq_get_active = gicv3_irq_get_active,
399 	.gic_irq_set_pending = gicv3_irq_set_pending,
400 	.gic_irq_clear_pending = gicv3_irq_clear_pending,
401 	.gic_irq_get_pending = gicv3_irq_get_pending,
402 	.gic_irq_set_config = gicv3_irq_set_config,
403 };
404 
405 void gic_rdist_enable_lpis(vm_paddr_t cfg_table, size_t cfg_table_size,
406 			   vm_paddr_t pend_table)
407 {
408 	volatile void *rdist_base = gicr_base_cpu(guest_get_vcpuid());
409 
410 	u32 ctlr;
411 	u64 val;
412 
413 	val = (cfg_table |
414 	       GICR_PROPBASER_InnerShareable |
415 	       GICR_PROPBASER_RaWaWb |
416 	       ((ilog2(cfg_table_size) - 1) & GICR_PROPBASER_IDBITS_MASK));
417 	writeq_relaxed(val, rdist_base + GICR_PROPBASER);
418 
419 	val = (pend_table |
420 	       GICR_PENDBASER_InnerShareable |
421 	       GICR_PENDBASER_RaWaWb);
422 	writeq_relaxed(val, rdist_base + GICR_PENDBASER);
423 
424 	ctlr = readl_relaxed(rdist_base + GICR_CTLR);
425 	ctlr |= GICR_CTLR_ENABLE_LPIS;
426 	writel_relaxed(ctlr, rdist_base + GICR_CTLR);
427 }
428