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