1 /*
2  * Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved.
3  * Portions copyright (c) 2021-2022, ProvenRun S.A.S. All rights reserved.
4  *
5  * SPDX-License-Identifier: BSD-3-Clause
6  */
7 
8 #include <assert.h>
9 #include <stdbool.h>
10 
11 #include <arch.h>
12 #include <arch_helpers.h>
13 #include <common/debug.h>
14 #include <common/interrupt_props.h>
15 #include <drivers/arm/gic_common.h>
16 #include <drivers/arm/gicv2.h>
17 #include <lib/spinlock.h>
18 
19 #include "../common/gic_common_private.h"
20 #include "gicv2_private.h"
21 
22 static const gicv2_driver_data_t *driver_data;
23 
24 /*
25  * Spinlock to guard registers needing read-modify-write. APIs protected by this
26  * spinlock are used either at boot time (when only a single CPU is active), or
27  * when the system is fully coherent.
28  */
29 static spinlock_t gic_lock;
30 
31 /*******************************************************************************
32  * Enable secure interrupts and use FIQs to route them. Disable legacy bypass
33  * and set the priority mask register to allow all interrupts to trickle in.
34  ******************************************************************************/
gicv2_cpuif_enable(void)35 void gicv2_cpuif_enable(void)
36 {
37 	unsigned int val;
38 
39 	assert(driver_data != NULL);
40 	assert(driver_data->gicc_base != 0U);
41 
42 	/*
43 	 * Enable the Group 0 interrupts, FIQEn and disable Group 0/1
44 	 * bypass.
45 	 */
46 	val = CTLR_ENABLE_G0_BIT | FIQ_EN_BIT | FIQ_BYP_DIS_GRP0;
47 	val |= IRQ_BYP_DIS_GRP0 | FIQ_BYP_DIS_GRP1 | IRQ_BYP_DIS_GRP1;
48 
49 	/* Program the idle priority in the PMR */
50 	gicc_write_pmr(driver_data->gicc_base, GIC_PRI_MASK);
51 	gicc_write_ctlr(driver_data->gicc_base, val);
52 }
53 
54 /*******************************************************************************
55  * Place the cpu interface in a state where it can never make a cpu exit wfi as
56  * as result of an asserted interrupt. This is critical for powering down a cpu
57  ******************************************************************************/
gicv2_cpuif_disable(void)58 void gicv2_cpuif_disable(void)
59 {
60 	unsigned int val;
61 
62 	assert(driver_data != NULL);
63 	assert(driver_data->gicc_base != 0U);
64 
65 	/* Disable secure, non-secure interrupts and disable their bypass */
66 	val = gicc_read_ctlr(driver_data->gicc_base);
67 	val &= ~(CTLR_ENABLE_G0_BIT | CTLR_ENABLE_G1_BIT);
68 	val |= FIQ_BYP_DIS_GRP1 | FIQ_BYP_DIS_GRP0;
69 	val |= IRQ_BYP_DIS_GRP0 | IRQ_BYP_DIS_GRP1;
70 	gicc_write_ctlr(driver_data->gicc_base, val);
71 }
72 
73 /*******************************************************************************
74  * Per cpu gic distributor setup which will be done by all cpus after a cold
75  * boot/hotplug. This marks out the secure SPIs and PPIs & enables them.
76  ******************************************************************************/
gicv2_pcpu_distif_init(void)77 void gicv2_pcpu_distif_init(void)
78 {
79 	unsigned int ctlr;
80 
81 	assert(driver_data != NULL);
82 	assert(driver_data->gicd_base != 0U);
83 
84 	gicv2_secure_ppi_sgi_setup_props(driver_data->gicd_base,
85 			driver_data->interrupt_props,
86 			driver_data->interrupt_props_num);
87 
88 	/* Enable G0 interrupts if not already */
89 	ctlr = gicd_read_ctlr(driver_data->gicd_base);
90 	if ((ctlr & CTLR_ENABLE_G0_BIT) == 0U) {
91 		gicd_write_ctlr(driver_data->gicd_base,
92 				ctlr | CTLR_ENABLE_G0_BIT);
93 	}
94 }
95 
96 /*******************************************************************************
97  * Global gic distributor init which will be done by the primary cpu after a
98  * cold boot. It marks out the secure SPIs, PPIs & SGIs and enables them. It
99  * then enables the secure GIC distributor interface.
100  ******************************************************************************/
gicv2_distif_init(void)101 void gicv2_distif_init(void)
102 {
103 	unsigned int ctlr;
104 
105 	assert(driver_data != NULL);
106 	assert(driver_data->gicd_base != 0U);
107 
108 	/* Disable the distributor before going further */
109 	ctlr = gicd_read_ctlr(driver_data->gicd_base);
110 	gicd_write_ctlr(driver_data->gicd_base,
111 			ctlr & ~(CTLR_ENABLE_G0_BIT | CTLR_ENABLE_G1_BIT));
112 
113 	/* Set the default attribute of all SPIs */
114 	gicv2_spis_configure_defaults(driver_data->gicd_base);
115 
116 	gicv2_secure_spis_configure_props(driver_data->gicd_base,
117 			driver_data->interrupt_props,
118 			driver_data->interrupt_props_num);
119 
120 
121 	/* Re-enable the secure SPIs now that they have been configured */
122 	gicd_write_ctlr(driver_data->gicd_base, ctlr | CTLR_ENABLE_G0_BIT);
123 }
124 
125 /*******************************************************************************
126  * Initialize the ARM GICv2 driver with the provided platform inputs
127  ******************************************************************************/
gicv2_driver_init(const gicv2_driver_data_t * plat_driver_data)128 void gicv2_driver_init(const gicv2_driver_data_t *plat_driver_data)
129 {
130 	unsigned int gic_version;
131 
132 	assert(plat_driver_data != NULL);
133 	assert(plat_driver_data->gicd_base != 0U);
134 	assert(plat_driver_data->gicc_base != 0U);
135 
136 	assert(plat_driver_data->interrupt_props_num > 0 ?
137 			plat_driver_data->interrupt_props != NULL : 1);
138 
139 	/* Ensure that this is a GICv2 system */
140 	gic_version = gicd_read_pidr2(plat_driver_data->gicd_base);
141 	gic_version = (gic_version >> PIDR2_ARCH_REV_SHIFT)
142 					& PIDR2_ARCH_REV_MASK;
143 
144 	/*
145 	 * GICv1 with security extension complies with trusted firmware
146 	 * GICv2 driver as far as virtualization and few tricky power
147 	 * features are not used. GICv2 features that are not supported
148 	 * by GICv1 with Security Extensions are:
149 	 * - virtual interrupt support.
150 	 * - wake up events.
151 	 * - writeable GIC state register (for power sequences)
152 	 * - interrupt priority drop.
153 	 * - interrupt signal bypass.
154 	 */
155 	assert((gic_version == ARCH_REV_GICV2) ||
156 	       (gic_version == ARCH_REV_GICV1));
157 
158 	driver_data = plat_driver_data;
159 
160 	/*
161 	 * The GIC driver data is initialized by the primary CPU with caches
162 	 * enabled. When the secondary CPU boots up, it initializes the
163 	 * GICC/GICR interface with the caches disabled. Hence flush the
164 	 * driver_data to ensure coherency. This is not required if the
165 	 * platform has HW_ASSISTED_COHERENCY or WARMBOOT_ENABLE_DCACHE_EARLY
166 	 * enabled.
167 	 */
168 #if !(HW_ASSISTED_COHERENCY || WARMBOOT_ENABLE_DCACHE_EARLY)
169 	flush_dcache_range((uintptr_t) &driver_data, sizeof(driver_data));
170 	flush_dcache_range((uintptr_t) driver_data, sizeof(*driver_data));
171 #endif
172 	INFO("ARM GICv2 driver initialized\n");
173 }
174 
175 /******************************************************************************
176  * This function returns whether FIQ is enabled in the GIC CPU interface.
177  *****************************************************************************/
gicv2_is_fiq_enabled(void)178 unsigned int gicv2_is_fiq_enabled(void)
179 {
180 	unsigned int gicc_ctlr;
181 
182 	assert(driver_data != NULL);
183 	assert(driver_data->gicc_base != 0U);
184 
185 	gicc_ctlr = gicc_read_ctlr(driver_data->gicc_base);
186 	return (gicc_ctlr >> FIQ_EN_SHIFT) & 0x1U;
187 }
188 
189 /*******************************************************************************
190  * This function returns the type of the highest priority pending interrupt at
191  * the GIC cpu interface. The return values can be one of the following :
192  *   PENDING_G1_INTID   : The interrupt type is non secure Group 1.
193  *   0 - 1019           : The interrupt type is secure Group 0.
194  *   GIC_SPURIOUS_INTERRUPT : there is no pending interrupt with
195  *                            sufficient priority to be signaled
196  ******************************************************************************/
gicv2_get_pending_interrupt_type(void)197 unsigned int gicv2_get_pending_interrupt_type(void)
198 {
199 	assert(driver_data != NULL);
200 	assert(driver_data->gicc_base != 0U);
201 
202 	return gicc_read_hppir(driver_data->gicc_base) & INT_ID_MASK;
203 }
204 
205 /*******************************************************************************
206  * This function returns the id of the highest priority pending interrupt at
207  * the GIC cpu interface. GIC_SPURIOUS_INTERRUPT is returned when there is no
208  * interrupt pending.
209  ******************************************************************************/
gicv2_get_pending_interrupt_id(void)210 unsigned int gicv2_get_pending_interrupt_id(void)
211 {
212 	unsigned int id;
213 
214 	assert(driver_data != NULL);
215 	assert(driver_data->gicc_base != 0U);
216 
217 	id = gicc_read_hppir(driver_data->gicc_base) & INT_ID_MASK;
218 
219 	/*
220 	 * Find out which non-secure interrupt it is under the assumption that
221 	 * the GICC_CTLR.AckCtl bit is 0.
222 	 */
223 	if (id == PENDING_G1_INTID)
224 		id = gicc_read_ahppir(driver_data->gicc_base) & INT_ID_MASK;
225 
226 	return id;
227 }
228 
229 /*******************************************************************************
230  * This functions reads the GIC cpu interface Interrupt Acknowledge register
231  * to start handling the pending secure 0 interrupt. It returns the
232  * contents of the IAR.
233  ******************************************************************************/
gicv2_acknowledge_interrupt(void)234 unsigned int gicv2_acknowledge_interrupt(void)
235 {
236 	assert(driver_data != NULL);
237 	assert(driver_data->gicc_base != 0U);
238 
239 	return gicc_read_IAR(driver_data->gicc_base);
240 }
241 
242 /*******************************************************************************
243  * This functions writes the GIC cpu interface End Of Interrupt register with
244  * the passed value to finish handling the active secure group 0 interrupt.
245  ******************************************************************************/
gicv2_end_of_interrupt(unsigned int id)246 void gicv2_end_of_interrupt(unsigned int id)
247 {
248 	assert(driver_data != NULL);
249 	assert(driver_data->gicc_base != 0U);
250 
251 	/*
252 	 * Ensure the write to peripheral registers are *complete* before the write
253 	 * to GIC_EOIR.
254 	 *
255 	 * Note: The completion gurantee depends on various factors of system design
256 	 * and the barrier is the best core can do by which execution of further
257 	 * instructions waits till the barrier is alive.
258 	 */
259 	dsbishst();
260 	gicc_write_EOIR(driver_data->gicc_base, id);
261 }
262 
263 /*******************************************************************************
264  * This function returns the type of the interrupt id depending upon the group
265  * this interrupt has been configured under by the interrupt controller i.e.
266  * group0 secure or group1 non secure. It returns zero for Group 0 secure and
267  * one for Group 1 non secure interrupt.
268  ******************************************************************************/
gicv2_get_interrupt_group(unsigned int id)269 unsigned int gicv2_get_interrupt_group(unsigned int id)
270 {
271 	assert(driver_data != NULL);
272 	assert(driver_data->gicd_base != 0U);
273 
274 	return gicd_get_igroupr(driver_data->gicd_base, id);
275 }
276 
277 /*******************************************************************************
278  * This function returns the priority of the interrupt the processor is
279  * currently servicing.
280  ******************************************************************************/
gicv2_get_running_priority(void)281 unsigned int gicv2_get_running_priority(void)
282 {
283 	assert(driver_data != NULL);
284 	assert(driver_data->gicc_base != 0U);
285 
286 	return gicc_read_rpr(driver_data->gicc_base);
287 }
288 
289 /*******************************************************************************
290  * This function sets the GICv2 target mask pattern for the current PE. The PE
291  * target mask is used to translate linear PE index (returned by platform core
292  * position) to a bit mask used when targeting interrupts to a PE (for example
293  * when raising SGIs and routing SPIs).
294  ******************************************************************************/
gicv2_set_pe_target_mask(unsigned int proc_num)295 void gicv2_set_pe_target_mask(unsigned int proc_num)
296 {
297 	assert(driver_data != NULL);
298 	assert(driver_data->gicd_base != 0U);
299 	assert(driver_data->target_masks != NULL);
300 	assert(proc_num < GICV2_MAX_TARGET_PE);
301 	assert(proc_num < driver_data->target_masks_num);
302 
303 	/* Return if the target mask is already populated */
304 	if (driver_data->target_masks[proc_num] != 0U)
305 		return;
306 
307 	/*
308 	 * Update target register corresponding to this CPU and flush for it to
309 	 * be visible to other CPUs.
310 	 */
311 	if (driver_data->target_masks[proc_num] == 0U) {
312 		driver_data->target_masks[proc_num] =
313 			gicv2_get_cpuif_id(driver_data->gicd_base);
314 #if !(HW_ASSISTED_COHERENCY || WARMBOOT_ENABLE_DCACHE_EARLY)
315 		/*
316 		 * PEs only update their own masks. Primary updates it with
317 		 * caches on. But because secondaries does it with caches off,
318 		 * all updates go to memory directly, and there's no danger of
319 		 * secondaries overwriting each others' mask, despite
320 		 * target_masks[] not being cache line aligned.
321 		 */
322 		flush_dcache_range((uintptr_t)
323 				&driver_data->target_masks[proc_num],
324 				sizeof(driver_data->target_masks[proc_num]));
325 #endif
326 	}
327 }
328 
329 /*******************************************************************************
330  * This function returns the active status of the interrupt (either because the
331  * state is active, or active and pending).
332  ******************************************************************************/
gicv2_get_interrupt_active(unsigned int id)333 unsigned int gicv2_get_interrupt_active(unsigned int id)
334 {
335 	assert(driver_data != NULL);
336 	assert(driver_data->gicd_base != 0U);
337 	assert(id <= MAX_SPI_ID);
338 
339 	return gicd_get_isactiver(driver_data->gicd_base, id);
340 }
341 
342 /*******************************************************************************
343  * This function enables the interrupt identified by id.
344  ******************************************************************************/
gicv2_enable_interrupt(unsigned int id)345 void gicv2_enable_interrupt(unsigned int id)
346 {
347 	assert(driver_data != NULL);
348 	assert(driver_data->gicd_base != 0U);
349 	assert(id <= MAX_SPI_ID);
350 
351 	/*
352 	 * Ensure that any shared variable updates depending on out of band
353 	 * interrupt trigger are observed before enabling interrupt.
354 	 */
355 	dsbishst();
356 	gicd_set_isenabler(driver_data->gicd_base, id);
357 }
358 
359 /*******************************************************************************
360  * This function disables the interrupt identified by id.
361  ******************************************************************************/
gicv2_disable_interrupt(unsigned int id)362 void gicv2_disable_interrupt(unsigned int id)
363 {
364 	assert(driver_data != NULL);
365 	assert(driver_data->gicd_base != 0U);
366 	assert(id <= MAX_SPI_ID);
367 
368 	/*
369 	 * Disable interrupt, and ensure that any shared variable updates
370 	 * depending on out of band interrupt trigger are observed afterwards.
371 	 */
372 	gicd_set_icenabler(driver_data->gicd_base, id);
373 	dsbishst();
374 }
375 
376 /*******************************************************************************
377  * This function sets the interrupt priority as supplied for the given interrupt
378  * id.
379  ******************************************************************************/
gicv2_set_interrupt_priority(unsigned int id,unsigned int priority)380 void gicv2_set_interrupt_priority(unsigned int id, unsigned int priority)
381 {
382 	assert(driver_data != NULL);
383 	assert(driver_data->gicd_base != 0U);
384 	assert(id <= MAX_SPI_ID);
385 
386 	gicd_set_ipriorityr(driver_data->gicd_base, id, priority);
387 }
388 
389 /*******************************************************************************
390  * This function assigns group for the interrupt identified by id. The group can
391  * be any of GICV2_INTR_GROUP*
392  ******************************************************************************/
gicv2_set_interrupt_type(unsigned int id,unsigned int type)393 void gicv2_set_interrupt_type(unsigned int id, unsigned int type)
394 {
395 	assert(driver_data != NULL);
396 	assert(driver_data->gicd_base != 0U);
397 	assert(id <= MAX_SPI_ID);
398 
399 	/* Serialize read-modify-write to Distributor registers */
400 	spin_lock(&gic_lock);
401 	switch (type) {
402 	case GICV2_INTR_GROUP1:
403 		gicd_set_igroupr(driver_data->gicd_base, id);
404 		break;
405 	case GICV2_INTR_GROUP0:
406 		gicd_clr_igroupr(driver_data->gicd_base, id);
407 		break;
408 	default:
409 		assert(false);
410 		break;
411 	}
412 	spin_unlock(&gic_lock);
413 }
414 
415 /*******************************************************************************
416  * This function raises the specified SGI to requested targets.
417  *
418  * The proc_num parameter must be the linear index of the target PE in the
419  * system.
420  ******************************************************************************/
gicv2_raise_sgi(int sgi_num,bool ns,int proc_num)421 void gicv2_raise_sgi(int sgi_num, bool ns, int proc_num)
422 {
423 	unsigned int sgir_val, target;
424 
425 	assert(driver_data != NULL);
426 	assert(proc_num >= 0);
427 	assert(proc_num < (int)GICV2_MAX_TARGET_PE);
428 	assert(driver_data->gicd_base != 0U);
429 
430 	/*
431 	 * Target masks array must have been supplied, and the core position
432 	 * should be valid.
433 	 */
434 	assert(driver_data->target_masks != NULL);
435 	assert(proc_num < (int)driver_data->target_masks_num);
436 
437 	/* Don't raise SGI if the mask hasn't been populated */
438 	target = driver_data->target_masks[proc_num];
439 	assert(target != 0U);
440 
441 	sgir_val = GICV2_SGIR_VALUE(SGIR_TGT_SPECIFIC, target, ns, sgi_num);
442 
443 	/*
444 	 * Ensure that any shared variable updates depending on out of band
445 	 * interrupt trigger are observed before raising SGI.
446 	 */
447 	dsbishst();
448 	gicd_write_sgir(driver_data->gicd_base, sgir_val);
449 }
450 
451 /*******************************************************************************
452  * This function sets the interrupt routing for the given SPI interrupt id.
453  * The interrupt routing is specified in routing mode. The proc_num parameter is
454  * linear index of the PE to target SPI. When proc_num < 0, the SPI may target
455  * all PEs.
456  ******************************************************************************/
gicv2_set_spi_routing(unsigned int id,int proc_num)457 void gicv2_set_spi_routing(unsigned int id, int proc_num)
458 {
459 	unsigned int target;
460 
461 	assert(driver_data != NULL);
462 	assert(driver_data->gicd_base != 0U);
463 
464 	assert((id >= MIN_SPI_ID) && (id <= MAX_SPI_ID));
465 
466 	/*
467 	 * Target masks array must have been supplied, and the core position
468 	 * should be valid.
469 	 */
470 	assert(driver_data->target_masks != NULL);
471 	assert(proc_num < (int)GICV2_MAX_TARGET_PE);
472 	assert(driver_data->target_masks_num < INT_MAX);
473 	assert(proc_num < (int)driver_data->target_masks_num);
474 
475 	if (proc_num < 0) {
476 		/* Target all PEs */
477 		target = GIC_TARGET_CPU_MASK;
478 	} else {
479 		/* Don't route interrupt if the mask hasn't been populated */
480 		target = driver_data->target_masks[proc_num];
481 		assert(target != 0U);
482 	}
483 
484 	gicd_set_itargetsr(driver_data->gicd_base, id, target);
485 }
486 
487 /*******************************************************************************
488  * This function clears the pending status of an interrupt identified by id.
489  ******************************************************************************/
gicv2_clear_interrupt_pending(unsigned int id)490 void gicv2_clear_interrupt_pending(unsigned int id)
491 {
492 	assert(driver_data != NULL);
493 	assert(driver_data->gicd_base != 0U);
494 
495 	/* SGIs can't be cleared pending */
496 	assert(id >= MIN_PPI_ID);
497 
498 	/*
499 	 * Clear pending interrupt, and ensure that any shared variable updates
500 	 * depending on out of band interrupt trigger are observed afterwards.
501 	 */
502 	gicd_set_icpendr(driver_data->gicd_base, id);
503 	dsbishst();
504 }
505 
506 /*******************************************************************************
507  * This function sets the pending status of an interrupt identified by id.
508  ******************************************************************************/
gicv2_set_interrupt_pending(unsigned int id)509 void gicv2_set_interrupt_pending(unsigned int id)
510 {
511 	assert(driver_data != NULL);
512 	assert(driver_data->gicd_base != 0U);
513 
514 	/* SGIs can't be cleared pending */
515 	assert(id >= MIN_PPI_ID);
516 
517 	/*
518 	 * Ensure that any shared variable updates depending on out of band
519 	 * interrupt trigger are observed before setting interrupt pending.
520 	 */
521 	dsbishst();
522 	gicd_set_ispendr(driver_data->gicd_base, id);
523 }
524 
525 /*******************************************************************************
526  * This function sets the PMR register with the supplied value. Returns the
527  * original PMR.
528  ******************************************************************************/
gicv2_set_pmr(unsigned int mask)529 unsigned int gicv2_set_pmr(unsigned int mask)
530 {
531 	unsigned int old_mask;
532 
533 	assert(driver_data != NULL);
534 	assert(driver_data->gicc_base != 0U);
535 
536 	old_mask = gicc_read_pmr(driver_data->gicc_base);
537 
538 	/*
539 	 * Order memory updates w.r.t. PMR write, and ensure they're visible
540 	 * before potential out of band interrupt trigger because of PMR update.
541 	 */
542 	dmbishst();
543 	gicc_write_pmr(driver_data->gicc_base, mask);
544 	dsbishst();
545 
546 	return old_mask;
547 }
548 
549 /*******************************************************************************
550  * This function updates single interrupt configuration to be level/edge
551  * triggered
552  ******************************************************************************/
gicv2_interrupt_set_cfg(unsigned int id,unsigned int cfg)553 void gicv2_interrupt_set_cfg(unsigned int id, unsigned int cfg)
554 {
555 	gicd_set_icfgr(driver_data->gicd_base, id, cfg);
556 }
557