xref: /linux/drivers/irqchip/irq-apple-aic.c (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright The Asahi Linux Contributors
4  *
5  * Based on irq-lpc32xx:
6  *   Copyright 2015-2016 Vladimir Zapolskiy <vz@mleia.com>
7  * Based on irq-bcm2836:
8  *   Copyright 2015 Broadcom
9  */
10 
11 /*
12  * AIC is a fairly simple interrupt controller with the following features:
13  *
14  * - 896 level-triggered hardware IRQs
15  *   - Single mask bit per IRQ
16  *   - Per-IRQ affinity setting
17  *   - Automatic masking on event delivery (auto-ack)
18  *   - Software triggering (ORed with hw line)
19  * - 2 per-CPU IPIs (meant as "self" and "other", but they are
20  *   interchangeable if not symmetric)
21  * - Automatic prioritization (single event/ack register per CPU, lower IRQs =
22  *   higher priority)
23  * - Automatic masking on ack
24  * - Default "this CPU" register view and explicit per-CPU views
25  *
26  * In addition, this driver also handles FIQs, as these are routed to the same
27  * IRQ vector. These are used for Fast IPIs, the ARMv8 timer IRQs, and
28  * performance counters (TODO).
29  *
30  * Implementation notes:
31  *
32  * - This driver creates two IRQ domains, one for HW IRQs and internal FIQs,
33  *   and one for IPIs.
34  * - Since Linux needs more than 2 IPIs, we implement a software IRQ controller
35  *   and funnel all IPIs into one per-CPU IPI (the second "self" IPI is unused).
36  * - FIQ hwirq numbers are assigned after true hwirqs, and are per-cpu.
37  * - DT bindings use 3-cell form (like GIC):
38  *   - <0 nr flags> - hwirq #nr
39  *   - <1 nr flags> - FIQ #nr
40  *     - nr=0  Physical HV timer
41  *     - nr=1  Virtual HV timer
42  *     - nr=2  Physical guest timer
43  *     - nr=3  Virtual guest timer
44  */
45 
46 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
47 
48 #include <linux/bits.h>
49 #include <linux/bitfield.h>
50 #include <linux/cpuhotplug.h>
51 #include <linux/io.h>
52 #include <linux/irqchip.h>
53 #include <linux/irqchip/arm-vgic-info.h>
54 #include <linux/irqdomain.h>
55 #include <linux/jump_label.h>
56 #include <linux/limits.h>
57 #include <linux/of_address.h>
58 #include <linux/slab.h>
59 #include <asm/apple_m1_pmu.h>
60 #include <asm/cputype.h>
61 #include <asm/exception.h>
62 #include <asm/sysreg.h>
63 #include <asm/virt.h>
64 
65 #include <dt-bindings/interrupt-controller/apple-aic.h>
66 
67 /*
68  * AIC v1 registers (MMIO)
69  */
70 
71 #define AIC_INFO		0x0004
72 #define AIC_INFO_NR_IRQ		GENMASK(15, 0)
73 
74 #define AIC_CONFIG		0x0010
75 
76 #define AIC_WHOAMI		0x2000
77 #define AIC_EVENT		0x2004
78 #define AIC_EVENT_DIE		GENMASK(31, 24)
79 #define AIC_EVENT_TYPE		GENMASK(23, 16)
80 #define AIC_EVENT_NUM		GENMASK(15, 0)
81 
82 #define AIC_EVENT_TYPE_FIQ	0 /* Software use */
83 #define AIC_EVENT_TYPE_IRQ	1
84 #define AIC_EVENT_TYPE_IPI	4
85 #define AIC_EVENT_IPI_OTHER	1
86 #define AIC_EVENT_IPI_SELF	2
87 
88 #define AIC_IPI_SEND		0x2008
89 #define AIC_IPI_ACK		0x200c
90 #define AIC_IPI_MASK_SET	0x2024
91 #define AIC_IPI_MASK_CLR	0x2028
92 
93 #define AIC_IPI_SEND_CPU(cpu)	BIT(cpu)
94 
95 #define AIC_IPI_OTHER		BIT(0)
96 #define AIC_IPI_SELF		BIT(31)
97 
98 #define AIC_TARGET_CPU		0x3000
99 
100 #define AIC_CPU_IPI_SET(cpu)	(0x5008 + ((cpu) << 7))
101 #define AIC_CPU_IPI_CLR(cpu)	(0x500c + ((cpu) << 7))
102 #define AIC_CPU_IPI_MASK_SET(cpu) (0x5024 + ((cpu) << 7))
103 #define AIC_CPU_IPI_MASK_CLR(cpu) (0x5028 + ((cpu) << 7))
104 
105 #define AIC_MAX_IRQ		0x400
106 
107 /*
108  * AIC v2 registers (MMIO)
109  */
110 
111 #define AIC2_VERSION		0x0000
112 #define AIC2_VERSION_VER	GENMASK(7, 0)
113 
114 #define AIC2_INFO1		0x0004
115 #define AIC2_INFO1_NR_IRQ	GENMASK(15, 0)
116 #define AIC2_INFO1_LAST_DIE	GENMASK(27, 24)
117 
118 #define AIC2_INFO2		0x0008
119 
120 #define AIC2_INFO3		0x000c
121 #define AIC2_INFO3_MAX_IRQ	GENMASK(15, 0)
122 #define AIC2_INFO3_MAX_DIE	GENMASK(27, 24)
123 
124 #define AIC2_RESET		0x0010
125 #define AIC2_RESET_RESET	BIT(0)
126 
127 #define AIC2_CONFIG		0x0014
128 #define AIC2_CONFIG_ENABLE	BIT(0)
129 #define AIC2_CONFIG_PREFER_PCPU	BIT(28)
130 
131 #define AIC2_TIMEOUT		0x0028
132 #define AIC2_CLUSTER_PRIO	0x0030
133 #define AIC2_DELAY_GROUPS	0x0100
134 
135 #define AIC2_IRQ_CFG		0x2000
136 
137 /*
138  * AIC2 registers are laid out like this, starting at AIC2_IRQ_CFG:
139  *
140  * Repeat for each die:
141  *   IRQ_CFG: u32 * MAX_IRQS
142  *   SW_SET: u32 * (MAX_IRQS / 32)
143  *   SW_CLR: u32 * (MAX_IRQS / 32)
144  *   MASK_SET: u32 * (MAX_IRQS / 32)
145  *   MASK_CLR: u32 * (MAX_IRQS / 32)
146  *   HW_STATE: u32 * (MAX_IRQS / 32)
147  *
148  * This is followed by a set of event registers, each 16K page aligned.
149  * The first one is the AP event register we will use. Unfortunately,
150  * the actual implemented die count is not specified anywhere in the
151  * capability registers, so we have to explicitly specify the event
152  * register as a second reg entry in the device tree to remain
153  * forward-compatible.
154  */
155 
156 #define AIC2_IRQ_CFG_TARGET	GENMASK(3, 0)
157 #define AIC2_IRQ_CFG_DELAY_IDX	GENMASK(7, 5)
158 
159 #define MASK_REG(x)		(4 * ((x) >> 5))
160 #define MASK_BIT(x)		BIT((x) & GENMASK(4, 0))
161 
162 /*
163  * IMP-DEF sysregs that control FIQ sources
164  */
165 
166 /* IPI request registers */
167 #define SYS_IMP_APL_IPI_RR_LOCAL_EL1	sys_reg(3, 5, 15, 0, 0)
168 #define SYS_IMP_APL_IPI_RR_GLOBAL_EL1	sys_reg(3, 5, 15, 0, 1)
169 #define IPI_RR_CPU			GENMASK(7, 0)
170 /* Cluster only used for the GLOBAL register */
171 #define IPI_RR_CLUSTER			GENMASK(23, 16)
172 #define IPI_RR_TYPE			GENMASK(29, 28)
173 #define IPI_RR_IMMEDIATE		0
174 #define IPI_RR_RETRACT			1
175 #define IPI_RR_DEFERRED			2
176 #define IPI_RR_NOWAKE			3
177 
178 /* IPI status register */
179 #define SYS_IMP_APL_IPI_SR_EL1		sys_reg(3, 5, 15, 1, 1)
180 #define IPI_SR_PENDING			BIT(0)
181 
182 /* Guest timer FIQ enable register */
183 #define SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2	sys_reg(3, 5, 15, 1, 3)
184 #define VM_TMR_FIQ_ENABLE_V		BIT(0)
185 #define VM_TMR_FIQ_ENABLE_P		BIT(1)
186 
187 /* Deferred IPI countdown register */
188 #define SYS_IMP_APL_IPI_CR_EL1		sys_reg(3, 5, 15, 3, 1)
189 
190 /* Uncore PMC control register */
191 #define SYS_IMP_APL_UPMCR0_EL1		sys_reg(3, 7, 15, 0, 4)
192 #define UPMCR0_IMODE			GENMASK(18, 16)
193 #define UPMCR0_IMODE_OFF		0
194 #define UPMCR0_IMODE_AIC		2
195 #define UPMCR0_IMODE_HALT		3
196 #define UPMCR0_IMODE_FIQ		4
197 
198 /* Uncore PMC status register */
199 #define SYS_IMP_APL_UPMSR_EL1		sys_reg(3, 7, 15, 6, 4)
200 #define UPMSR_IACT			BIT(0)
201 
202 /* MPIDR fields */
203 #define MPIDR_CPU(x)			MPIDR_AFFINITY_LEVEL(x, 0)
204 #define MPIDR_CLUSTER(x)		MPIDR_AFFINITY_LEVEL(x, 1)
205 
206 #define AIC_IRQ_HWIRQ(die, irq)	(FIELD_PREP(AIC_EVENT_DIE, die) | \
207 				 FIELD_PREP(AIC_EVENT_TYPE, AIC_EVENT_TYPE_IRQ) | \
208 				 FIELD_PREP(AIC_EVENT_NUM, irq))
209 #define AIC_FIQ_HWIRQ(x)	(FIELD_PREP(AIC_EVENT_TYPE, AIC_EVENT_TYPE_FIQ) | \
210 				 FIELD_PREP(AIC_EVENT_NUM, x))
211 #define AIC_HWIRQ_IRQ(x)	FIELD_GET(AIC_EVENT_NUM, x)
212 #define AIC_HWIRQ_DIE(x)	FIELD_GET(AIC_EVENT_DIE, x)
213 #define AIC_NR_SWIPI		32
214 
215 /*
216  * FIQ hwirq index definitions: FIQ sources use the DT binding defines
217  * directly, except that timers are special. At the irqchip level, the
218  * two timer types are represented by their access method: _EL0 registers
219  * or _EL02 registers. In the DT binding, the timers are represented
220  * by their purpose (HV or guest). This mapping is for when the kernel is
221  * running at EL2 (with VHE). When the kernel is running at EL1, the
222  * mapping differs and aic_irq_domain_translate() performs the remapping.
223  */
224 enum fiq_hwirq {
225 	/* Must be ordered as in apple-aic.h */
226 	AIC_TMR_EL0_PHYS	= AIC_TMR_HV_PHYS,
227 	AIC_TMR_EL0_VIRT	= AIC_TMR_HV_VIRT,
228 	AIC_TMR_EL02_PHYS	= AIC_TMR_GUEST_PHYS,
229 	AIC_TMR_EL02_VIRT	= AIC_TMR_GUEST_VIRT,
230 	AIC_CPU_PMU_Effi	= AIC_CPU_PMU_E,
231 	AIC_CPU_PMU_Perf	= AIC_CPU_PMU_P,
232 	/* No need for this to be discovered from DT */
233 	AIC_VGIC_MI,
234 	AIC_NR_FIQ
235 };
236 
237 /* True if UNCORE/UNCORE2 and Sn_... IPI registers are present and used (A11+) */
238 static DEFINE_STATIC_KEY_TRUE(use_fast_ipi);
239 /* True if SYS_IMP_APL_IPI_RR_LOCAL_EL1 exists for local fast IPIs (M1+) */
240 static DEFINE_STATIC_KEY_TRUE(use_local_fast_ipi);
241 
242 struct aic_info {
243 	int version;
244 
245 	/* Register offsets */
246 	u32 event;
247 	u32 target_cpu;
248 	u32 irq_cfg;
249 	u32 sw_set;
250 	u32 sw_clr;
251 	u32 mask_set;
252 	u32 mask_clr;
253 
254 	u32 die_stride;
255 
256 	/* Features */
257 	bool fast_ipi;
258 	bool local_fast_ipi;
259 };
260 
261 static const struct aic_info aic1_info __initconst = {
262 	.version	= 1,
263 
264 	.event		= AIC_EVENT,
265 	.target_cpu	= AIC_TARGET_CPU,
266 };
267 
268 static const struct aic_info aic1_fipi_info __initconst = {
269 	.version	= 1,
270 
271 	.event		= AIC_EVENT,
272 	.target_cpu	= AIC_TARGET_CPU,
273 
274 	.fast_ipi	= true,
275 };
276 
277 static const struct aic_info aic1_local_fipi_info __initconst = {
278 	.version	= 1,
279 
280 	.event		= AIC_EVENT,
281 	.target_cpu	= AIC_TARGET_CPU,
282 
283 	.fast_ipi	= true,
284 	.local_fast_ipi = true,
285 };
286 
287 static const struct aic_info aic2_info __initconst = {
288 	.version	= 2,
289 
290 	.irq_cfg	= AIC2_IRQ_CFG,
291 
292 	.fast_ipi	= true,
293 	.local_fast_ipi = true,
294 };
295 
296 static const struct of_device_id aic_info_match[] = {
297 	{
298 		.compatible = "apple,t8103-aic",
299 		.data = &aic1_local_fipi_info,
300 	},
301 	{
302 		.compatible = "apple,t8015-aic",
303 		.data = &aic1_fipi_info,
304 	},
305 	{
306 		.compatible = "apple,aic",
307 		.data = &aic1_info,
308 	},
309 	{
310 		.compatible = "apple,aic2",
311 		.data = &aic2_info,
312 	},
313 	{}
314 };
315 
316 struct aic_irq_chip {
317 	void __iomem *base;
318 	void __iomem *event;
319 	struct irq_domain *hw_domain;
320 	struct {
321 		cpumask_t aff;
322 	} *fiq_aff[AIC_NR_FIQ];
323 
324 	int nr_irq;
325 	int max_irq;
326 	int nr_die;
327 	int max_die;
328 
329 	struct aic_info info;
330 };
331 
332 static DEFINE_PER_CPU(uint32_t, aic_fiq_unmasked);
333 
334 static struct aic_irq_chip *aic_irqc;
335 
336 static void aic_handle_ipi(struct pt_regs *regs);
337 
aic_ic_read(struct aic_irq_chip * ic,u32 reg)338 static u32 aic_ic_read(struct aic_irq_chip *ic, u32 reg)
339 {
340 	return readl_relaxed(ic->base + reg);
341 }
342 
aic_ic_write(struct aic_irq_chip * ic,u32 reg,u32 val)343 static void aic_ic_write(struct aic_irq_chip *ic, u32 reg, u32 val)
344 {
345 	writel_relaxed(val, ic->base + reg);
346 }
347 
348 /*
349  * IRQ irqchip
350  */
351 
aic_irq_mask(struct irq_data * d)352 static void aic_irq_mask(struct irq_data *d)
353 {
354 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
355 	struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d);
356 
357 	u32 off = AIC_HWIRQ_DIE(hwirq) * ic->info.die_stride;
358 	u32 irq = AIC_HWIRQ_IRQ(hwirq);
359 
360 	aic_ic_write(ic, ic->info.mask_set + off + MASK_REG(irq), MASK_BIT(irq));
361 }
362 
aic_irq_unmask(struct irq_data * d)363 static void aic_irq_unmask(struct irq_data *d)
364 {
365 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
366 	struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d);
367 
368 	u32 off = AIC_HWIRQ_DIE(hwirq) * ic->info.die_stride;
369 	u32 irq = AIC_HWIRQ_IRQ(hwirq);
370 
371 	aic_ic_write(ic, ic->info.mask_clr + off + MASK_REG(irq), MASK_BIT(irq));
372 }
373 
aic_irq_eoi(struct irq_data * d)374 static void aic_irq_eoi(struct irq_data *d)
375 {
376 	/*
377 	 * Reading the interrupt reason automatically acknowledges and masks
378 	 * the IRQ, so we just unmask it here if needed.
379 	 */
380 	if (!irqd_irq_masked(d))
381 		aic_irq_unmask(d);
382 }
383 
aic_handle_irq(struct pt_regs * regs)384 static void __exception_irq_entry aic_handle_irq(struct pt_regs *regs)
385 {
386 	struct aic_irq_chip *ic = aic_irqc;
387 	u32 event, type, irq;
388 
389 	do {
390 		/*
391 		 * We cannot use a relaxed read here, as reads from DMA buffers
392 		 * need to be ordered after the IRQ fires.
393 		 */
394 		event = readl(ic->event + ic->info.event);
395 		type = FIELD_GET(AIC_EVENT_TYPE, event);
396 		irq = FIELD_GET(AIC_EVENT_NUM, event);
397 
398 		if (type == AIC_EVENT_TYPE_IRQ)
399 			generic_handle_domain_irq(aic_irqc->hw_domain, event);
400 		else if (type == AIC_EVENT_TYPE_IPI && irq == 1)
401 			aic_handle_ipi(regs);
402 		else if (event != 0)
403 			pr_err_ratelimited("Unknown IRQ event %d, %d\n", type, irq);
404 	} while (event);
405 
406 	/*
407 	 * vGIC maintenance interrupts end up here too, so we need to check
408 	 * for them separately. It should however only trigger when NV is
409 	 * in use, and be cleared when coming back from the handler.
410 	 */
411 	if (is_kernel_in_hyp_mode() &&
412 	    (read_sysreg_s(SYS_ICH_HCR_EL2) & ICH_HCR_EN) &&
413 	    read_sysreg_s(SYS_ICH_MISR_EL2) != 0) {
414 		generic_handle_domain_irq(aic_irqc->hw_domain,
415 					  AIC_FIQ_HWIRQ(AIC_VGIC_MI));
416 
417 		if (unlikely((read_sysreg_s(SYS_ICH_HCR_EL2) & ICH_HCR_EN) &&
418 			     read_sysreg_s(SYS_ICH_MISR_EL2))) {
419 			pr_err_ratelimited("vGIC IRQ fired and not handled by KVM, disabling.\n");
420 			sysreg_clear_set_s(SYS_ICH_HCR_EL2, ICH_HCR_EN, 0);
421 		}
422 	}
423 }
424 
aic_irq_set_affinity(struct irq_data * d,const struct cpumask * mask_val,bool force)425 static int aic_irq_set_affinity(struct irq_data *d,
426 				const struct cpumask *mask_val, bool force)
427 {
428 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
429 	struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d);
430 	int cpu;
431 
432 	BUG_ON(!ic->info.target_cpu);
433 
434 	if (force)
435 		cpu = cpumask_first(mask_val);
436 	else
437 		cpu = cpumask_any_and(mask_val, cpu_online_mask);
438 
439 	aic_ic_write(ic, ic->info.target_cpu + AIC_HWIRQ_IRQ(hwirq) * 4, BIT(cpu));
440 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
441 
442 	return IRQ_SET_MASK_OK;
443 }
444 
aic_irq_set_type(struct irq_data * d,unsigned int type)445 static int aic_irq_set_type(struct irq_data *d, unsigned int type)
446 {
447 	/*
448 	 * Some IRQs (e.g. MSIs) implicitly have edge semantics, and we don't
449 	 * have a way to find out the type of any given IRQ, so just allow both.
450 	 */
451 	return (type == IRQ_TYPE_LEVEL_HIGH || type == IRQ_TYPE_EDGE_RISING) ? 0 : -EINVAL;
452 }
453 
454 static struct irq_chip aic_chip = {
455 	.name = "AIC",
456 	.irq_mask = aic_irq_mask,
457 	.irq_unmask = aic_irq_unmask,
458 	.irq_eoi = aic_irq_eoi,
459 	.irq_set_affinity = aic_irq_set_affinity,
460 	.irq_set_type = aic_irq_set_type,
461 };
462 
463 static struct irq_chip aic2_chip = {
464 	.name = "AIC2",
465 	.irq_mask = aic_irq_mask,
466 	.irq_unmask = aic_irq_unmask,
467 	.irq_eoi = aic_irq_eoi,
468 	.irq_set_type = aic_irq_set_type,
469 };
470 
471 /*
472  * FIQ irqchip
473  */
474 
aic_fiq_get_idx(struct irq_data * d)475 static unsigned long aic_fiq_get_idx(struct irq_data *d)
476 {
477 	return AIC_HWIRQ_IRQ(irqd_to_hwirq(d));
478 }
479 
aic_fiq_set_mask(struct irq_data * d)480 static void aic_fiq_set_mask(struct irq_data *d)
481 {
482 	/* Only the guest timers have real mask bits, unfortunately. */
483 	switch (aic_fiq_get_idx(d)) {
484 	case AIC_TMR_EL02_PHYS:
485 		sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, VM_TMR_FIQ_ENABLE_P, 0);
486 		isb();
487 		break;
488 	case AIC_TMR_EL02_VIRT:
489 		sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, VM_TMR_FIQ_ENABLE_V, 0);
490 		isb();
491 		break;
492 	default:
493 		break;
494 	}
495 }
496 
aic_fiq_clear_mask(struct irq_data * d)497 static void aic_fiq_clear_mask(struct irq_data *d)
498 {
499 	switch (aic_fiq_get_idx(d)) {
500 	case AIC_TMR_EL02_PHYS:
501 		sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, 0, VM_TMR_FIQ_ENABLE_P);
502 		isb();
503 		break;
504 	case AIC_TMR_EL02_VIRT:
505 		sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, 0, VM_TMR_FIQ_ENABLE_V);
506 		isb();
507 		break;
508 	default:
509 		break;
510 	}
511 }
512 
aic_fiq_mask(struct irq_data * d)513 static void aic_fiq_mask(struct irq_data *d)
514 {
515 	aic_fiq_set_mask(d);
516 	__this_cpu_and(aic_fiq_unmasked, ~BIT(aic_fiq_get_idx(d)));
517 }
518 
aic_fiq_unmask(struct irq_data * d)519 static void aic_fiq_unmask(struct irq_data *d)
520 {
521 	aic_fiq_clear_mask(d);
522 	__this_cpu_or(aic_fiq_unmasked, BIT(aic_fiq_get_idx(d)));
523 }
524 
aic_fiq_eoi(struct irq_data * d)525 static void aic_fiq_eoi(struct irq_data *d)
526 {
527 	/* We mask to ack (where we can), so we need to unmask at EOI. */
528 	if (__this_cpu_read(aic_fiq_unmasked) & BIT(aic_fiq_get_idx(d)))
529 		aic_fiq_clear_mask(d);
530 }
531 
532 #define TIMER_FIRING(x)                                                        \
533 	(((x) & (ARCH_TIMER_CTRL_ENABLE | ARCH_TIMER_CTRL_IT_MASK |            \
534 		 ARCH_TIMER_CTRL_IT_STAT)) ==                                  \
535 	 (ARCH_TIMER_CTRL_ENABLE | ARCH_TIMER_CTRL_IT_STAT))
536 
aic_handle_fiq(struct pt_regs * regs)537 static void __exception_irq_entry aic_handle_fiq(struct pt_regs *regs)
538 {
539 	/*
540 	 * It would be really nice if we had a system register that lets us get
541 	 * the FIQ source state without having to peek down into sources...
542 	 * but such a register does not seem to exist.
543 	 *
544 	 * So, we have these potential sources to test for:
545 	 *  - Fast IPIs (not yet used)
546 	 *  - The 4 timers (CNTP, CNTV for each of HV and guest)
547 	 *  - Per-core PMCs (not yet supported)
548 	 *  - Per-cluster uncore PMCs (not yet supported)
549 	 *
550 	 * Since not dealing with any of these results in a FIQ storm,
551 	 * we check for everything here, even things we don't support yet.
552 	 */
553 
554 	if (static_branch_likely(&use_fast_ipi) &&
555 	    (read_sysreg_s(SYS_IMP_APL_IPI_SR_EL1) & IPI_SR_PENDING))
556 		aic_handle_ipi(regs);
557 
558 	if (TIMER_FIRING(read_sysreg(cntp_ctl_el0)))
559 		generic_handle_domain_irq(aic_irqc->hw_domain,
560 					  AIC_FIQ_HWIRQ(AIC_TMR_EL0_PHYS));
561 
562 	if (TIMER_FIRING(read_sysreg(cntv_ctl_el0)))
563 		generic_handle_domain_irq(aic_irqc->hw_domain,
564 					  AIC_FIQ_HWIRQ(AIC_TMR_EL0_VIRT));
565 
566 	if (is_kernel_in_hyp_mode()) {
567 		uint64_t enabled = read_sysreg_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2);
568 
569 		if ((enabled & VM_TMR_FIQ_ENABLE_P) &&
570 		    TIMER_FIRING(read_sysreg_s(SYS_CNTP_CTL_EL02)))
571 			generic_handle_domain_irq(aic_irqc->hw_domain,
572 						  AIC_FIQ_HWIRQ(AIC_TMR_EL02_PHYS));
573 
574 		if ((enabled & VM_TMR_FIQ_ENABLE_V) &&
575 		    TIMER_FIRING(read_sysreg_s(SYS_CNTV_CTL_EL02)))
576 			generic_handle_domain_irq(aic_irqc->hw_domain,
577 						  AIC_FIQ_HWIRQ(AIC_TMR_EL02_VIRT));
578 	}
579 
580 	if (read_sysreg_s(SYS_IMP_APL_PMCR0_EL1) & PMCR0_IACT) {
581 		int irq;
582 		if (cpumask_test_cpu(smp_processor_id(),
583 				     &aic_irqc->fiq_aff[AIC_CPU_PMU_P]->aff))
584 			irq = AIC_CPU_PMU_P;
585 		else
586 			irq = AIC_CPU_PMU_E;
587 		generic_handle_domain_irq(aic_irqc->hw_domain,
588 					  AIC_FIQ_HWIRQ(irq));
589 	}
590 
591 	if (static_branch_likely(&use_fast_ipi) &&
592 	    (FIELD_GET(UPMCR0_IMODE, read_sysreg_s(SYS_IMP_APL_UPMCR0_EL1)) == UPMCR0_IMODE_FIQ) &&
593 	    (read_sysreg_s(SYS_IMP_APL_UPMSR_EL1) & UPMSR_IACT)) {
594 		/* Same story with uncore PMCs */
595 		pr_err_ratelimited("Uncore PMC FIQ fired. Masking.\n");
596 		sysreg_clear_set_s(SYS_IMP_APL_UPMCR0_EL1, UPMCR0_IMODE,
597 				   FIELD_PREP(UPMCR0_IMODE, UPMCR0_IMODE_OFF));
598 	}
599 }
600 
aic_fiq_set_type(struct irq_data * d,unsigned int type)601 static int aic_fiq_set_type(struct irq_data *d, unsigned int type)
602 {
603 	return (type == IRQ_TYPE_LEVEL_HIGH) ? 0 : -EINVAL;
604 }
605 
606 static struct irq_chip fiq_chip = {
607 	.name = "AIC-FIQ",
608 	.irq_mask = aic_fiq_mask,
609 	.irq_unmask = aic_fiq_unmask,
610 	.irq_ack = aic_fiq_set_mask,
611 	.irq_eoi = aic_fiq_eoi,
612 	.irq_set_type = aic_fiq_set_type,
613 };
614 
615 /*
616  * Main IRQ domain
617  */
618 
aic_irq_domain_map(struct irq_domain * id,unsigned int irq,irq_hw_number_t hw)619 static int aic_irq_domain_map(struct irq_domain *id, unsigned int irq,
620 			      irq_hw_number_t hw)
621 {
622 	struct aic_irq_chip *ic = id->host_data;
623 	u32 type = FIELD_GET(AIC_EVENT_TYPE, hw);
624 	struct irq_chip *chip = &aic_chip;
625 
626 	if (ic->info.version == 2)
627 		chip = &aic2_chip;
628 
629 	if (type == AIC_EVENT_TYPE_IRQ) {
630 		irq_domain_set_info(id, irq, hw, chip, id->host_data,
631 				    handle_fasteoi_irq, NULL, NULL);
632 		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(irq)));
633 	} else {
634 		int fiq = FIELD_GET(AIC_EVENT_NUM, hw);
635 
636 		switch (fiq) {
637 		case AIC_CPU_PMU_P:
638 		case AIC_CPU_PMU_E:
639 			irq_set_percpu_devid_partition(irq, &ic->fiq_aff[fiq]->aff);
640 			break;
641 		default:
642 			irq_set_percpu_devid(irq);
643 			break;
644 		}
645 
646 		irq_domain_set_info(id, irq, hw, &fiq_chip, id->host_data,
647 				    handle_percpu_devid_irq, NULL, NULL);
648 	}
649 
650 	return 0;
651 }
652 
aic_irq_domain_translate(struct irq_domain * id,struct irq_fwspec * fwspec,unsigned long * hwirq,unsigned int * type)653 static int aic_irq_domain_translate(struct irq_domain *id,
654 				    struct irq_fwspec *fwspec,
655 				    unsigned long *hwirq,
656 				    unsigned int *type)
657 {
658 	struct aic_irq_chip *ic = id->host_data;
659 	u32 *args;
660 	u32 die = 0;
661 
662 	if (fwspec->param_count < 3 || fwspec->param_count > 4 ||
663 	    !is_of_node(fwspec->fwnode))
664 		return -EINVAL;
665 
666 	args = &fwspec->param[1];
667 
668 	if (fwspec->param_count == 4) {
669 		die = args[0];
670 		args++;
671 	}
672 
673 	switch (fwspec->param[0]) {
674 	case AIC_IRQ:
675 		if (die >= ic->nr_die)
676 			return -EINVAL;
677 		if (args[0] >= ic->nr_irq)
678 			return -EINVAL;
679 		*hwirq = AIC_IRQ_HWIRQ(die, args[0]);
680 		break;
681 	case AIC_FIQ:
682 		if (die != 0)
683 			return -EINVAL;
684 		if (args[0] >= AIC_NR_FIQ)
685 			return -EINVAL;
686 		*hwirq = AIC_FIQ_HWIRQ(args[0]);
687 
688 		/*
689 		 * In EL1 the non-redirected registers are the guest's,
690 		 * not EL2's, so remap the hwirqs to match.
691 		 */
692 		if (!is_kernel_in_hyp_mode()) {
693 			switch (args[0]) {
694 			case AIC_TMR_GUEST_PHYS:
695 				*hwirq = AIC_FIQ_HWIRQ(AIC_TMR_EL0_PHYS);
696 				break;
697 			case AIC_TMR_GUEST_VIRT:
698 				*hwirq = AIC_FIQ_HWIRQ(AIC_TMR_EL0_VIRT);
699 				break;
700 			case AIC_TMR_HV_PHYS:
701 			case AIC_TMR_HV_VIRT:
702 				return -ENOENT;
703 			default:
704 				break;
705 			}
706 		}
707 		break;
708 	default:
709 		return -EINVAL;
710 	}
711 
712 	*type = args[1] & IRQ_TYPE_SENSE_MASK;
713 
714 	return 0;
715 }
716 
aic_irq_domain_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * arg)717 static int aic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
718 				unsigned int nr_irqs, void *arg)
719 {
720 	unsigned int type = IRQ_TYPE_NONE;
721 	struct irq_fwspec *fwspec = arg;
722 	irq_hw_number_t hwirq;
723 	int i, ret;
724 
725 	ret = aic_irq_domain_translate(domain, fwspec, &hwirq, &type);
726 	if (ret)
727 		return ret;
728 
729 	for (i = 0; i < nr_irqs; i++) {
730 		ret = aic_irq_domain_map(domain, virq + i, hwirq + i);
731 		if (ret)
732 			return ret;
733 	}
734 
735 	return 0;
736 }
737 
aic_irq_domain_free(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs)738 static void aic_irq_domain_free(struct irq_domain *domain, unsigned int virq,
739 				unsigned int nr_irqs)
740 {
741 	int i;
742 
743 	for (i = 0; i < nr_irqs; i++) {
744 		struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
745 
746 		irq_set_handler(virq + i, NULL);
747 		irq_domain_reset_irq_data(d);
748 	}
749 }
750 
751 static const struct irq_domain_ops aic_irq_domain_ops = {
752 	.translate	= aic_irq_domain_translate,
753 	.alloc		= aic_irq_domain_alloc,
754 	.free		= aic_irq_domain_free,
755 };
756 
757 /*
758  * IPI irqchip
759  */
760 
aic_ipi_send_fast(int cpu)761 static void aic_ipi_send_fast(int cpu)
762 {
763 	u64 mpidr = cpu_logical_map(cpu);
764 	u64 my_mpidr = read_cpuid_mpidr();
765 	u64 cluster = MPIDR_CLUSTER(mpidr);
766 	u64 idx = MPIDR_CPU(mpidr);
767 
768 	if (static_branch_likely(&use_local_fast_ipi) && MPIDR_CLUSTER(my_mpidr) == cluster) {
769 		write_sysreg_s(FIELD_PREP(IPI_RR_CPU, idx), SYS_IMP_APL_IPI_RR_LOCAL_EL1);
770 	} else {
771 		write_sysreg_s(FIELD_PREP(IPI_RR_CPU, idx) | FIELD_PREP(IPI_RR_CLUSTER, cluster),
772 			       SYS_IMP_APL_IPI_RR_GLOBAL_EL1);
773 	}
774 	isb();
775 }
776 
aic_handle_ipi(struct pt_regs * regs)777 static void aic_handle_ipi(struct pt_regs *regs)
778 {
779 	/*
780 	 * Ack the IPI. We need to order this after the AIC event read, but
781 	 * that is enforced by normal MMIO ordering guarantees.
782 	 *
783 	 * For the Fast IPI case, this needs to be ordered before the vIPI
784 	 * handling below, so we need to isb();
785 	 */
786 	if (static_branch_likely(&use_fast_ipi)) {
787 		write_sysreg_s(IPI_SR_PENDING, SYS_IMP_APL_IPI_SR_EL1);
788 		isb();
789 	} else {
790 		aic_ic_write(aic_irqc, AIC_IPI_ACK, AIC_IPI_OTHER);
791 	}
792 
793 	ipi_mux_process();
794 
795 	/*
796 	 * No ordering needed here; at worst this just changes the timing of
797 	 * when the next IPI will be delivered.
798 	 */
799 	if (!static_branch_likely(&use_fast_ipi))
800 		aic_ic_write(aic_irqc, AIC_IPI_MASK_CLR, AIC_IPI_OTHER);
801 }
802 
aic_ipi_send_single(unsigned int cpu)803 static void aic_ipi_send_single(unsigned int cpu)
804 {
805 	if (static_branch_likely(&use_fast_ipi))
806 		aic_ipi_send_fast(cpu);
807 	else
808 		aic_ic_write(aic_irqc, AIC_IPI_SEND, AIC_IPI_SEND_CPU(cpu));
809 }
810 
aic_init_smp(struct aic_irq_chip * irqc,struct device_node * node)811 static int __init aic_init_smp(struct aic_irq_chip *irqc, struct device_node *node)
812 {
813 	int base_ipi;
814 
815 	base_ipi = ipi_mux_create(AIC_NR_SWIPI, aic_ipi_send_single);
816 	if (WARN_ON(base_ipi <= 0))
817 		return -ENODEV;
818 
819 	set_smp_ipi_range(base_ipi, AIC_NR_SWIPI);
820 
821 	return 0;
822 }
823 
aic_init_cpu(unsigned int cpu)824 static int aic_init_cpu(unsigned int cpu)
825 {
826 	/* Mask all hard-wired per-CPU IRQ/FIQ sources */
827 
828 	/* Pending Fast IPI FIQs */
829 	if (static_branch_likely(&use_fast_ipi))
830 		write_sysreg_s(IPI_SR_PENDING, SYS_IMP_APL_IPI_SR_EL1);
831 
832 	/* Timer FIQs */
833 	sysreg_clear_set(cntp_ctl_el0, 0, ARCH_TIMER_CTRL_IT_MASK);
834 	sysreg_clear_set(cntv_ctl_el0, 0, ARCH_TIMER_CTRL_IT_MASK);
835 
836 	/* EL2-only (VHE mode) IRQ sources */
837 	if (is_kernel_in_hyp_mode()) {
838 		/* Guest timers */
839 		sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2,
840 				   VM_TMR_FIQ_ENABLE_V | VM_TMR_FIQ_ENABLE_P, 0);
841 
842 		/* vGIC maintenance IRQ */
843 		sysreg_clear_set_s(SYS_ICH_HCR_EL2, ICH_HCR_EN, 0);
844 	}
845 
846 	/* PMC FIQ */
847 	sysreg_clear_set_s(SYS_IMP_APL_PMCR0_EL1, PMCR0_IMODE | PMCR0_IACT,
848 			   FIELD_PREP(PMCR0_IMODE, PMCR0_IMODE_OFF));
849 
850 	/* Uncore PMC FIQ */
851 	if (static_branch_likely(&use_fast_ipi)) {
852 		sysreg_clear_set_s(SYS_IMP_APL_UPMCR0_EL1, UPMCR0_IMODE,
853 				   FIELD_PREP(UPMCR0_IMODE, UPMCR0_IMODE_OFF));
854 	}
855 
856 	/* Commit all of the above */
857 	isb();
858 
859 	if (aic_irqc->info.version == 1) {
860 		/*
861 		 * Make sure the kernel's idea of logical CPU order is the same as AIC's
862 		 * If we ever end up with a mismatch here, we will have to introduce
863 		 * a mapping table similar to what other irqchip drivers do.
864 		 */
865 		WARN_ON(aic_ic_read(aic_irqc, AIC_WHOAMI) != smp_processor_id());
866 
867 		/*
868 		 * Always keep IPIs unmasked at the hardware level (except auto-masking
869 		 * by AIC during processing). We manage masks at the vIPI level.
870 		 * These registers only exist on AICv1, AICv2 always uses fast IPIs.
871 		 */
872 		aic_ic_write(aic_irqc, AIC_IPI_ACK, AIC_IPI_SELF | AIC_IPI_OTHER);
873 		if (static_branch_likely(&use_fast_ipi)) {
874 			aic_ic_write(aic_irqc, AIC_IPI_MASK_SET, AIC_IPI_SELF | AIC_IPI_OTHER);
875 		} else {
876 			aic_ic_write(aic_irqc, AIC_IPI_MASK_SET, AIC_IPI_SELF);
877 			aic_ic_write(aic_irqc, AIC_IPI_MASK_CLR, AIC_IPI_OTHER);
878 		}
879 	}
880 
881 	/* Initialize the local mask state */
882 	__this_cpu_write(aic_fiq_unmasked, 0);
883 
884 	return 0;
885 }
886 
887 static struct gic_kvm_info vgic_info __initdata = {
888 	.type			= GIC_V3,
889 	.no_maint_irq_mask	= true,
890 	.no_hw_deactivation	= true,
891 };
892 
build_fiq_affinity(struct aic_irq_chip * ic,struct device_node * aff)893 static void build_fiq_affinity(struct aic_irq_chip *ic, struct device_node *aff)
894 {
895 	int i, n;
896 	u32 fiq;
897 
898 	if (of_property_read_u32(aff, "apple,fiq-index", &fiq) ||
899 	    WARN_ON(fiq >= AIC_NR_FIQ) || ic->fiq_aff[fiq])
900 		return;
901 
902 	n = of_property_count_elems_of_size(aff, "cpus", sizeof(u32));
903 	if (WARN_ON(n < 0))
904 		return;
905 
906 	ic->fiq_aff[fiq] = kzalloc(sizeof(*ic->fiq_aff[fiq]), GFP_KERNEL);
907 	if (!ic->fiq_aff[fiq])
908 		return;
909 
910 	for (i = 0; i < n; i++) {
911 		struct device_node *cpu_node;
912 		u32 cpu_phandle;
913 		int cpu;
914 
915 		if (of_property_read_u32_index(aff, "cpus", i, &cpu_phandle))
916 			continue;
917 
918 		cpu_node = of_find_node_by_phandle(cpu_phandle);
919 		if (WARN_ON(!cpu_node))
920 			continue;
921 
922 		cpu = of_cpu_node_to_id(cpu_node);
923 		of_node_put(cpu_node);
924 		if (WARN_ON(cpu < 0))
925 			continue;
926 
927 		cpumask_set_cpu(cpu, &ic->fiq_aff[fiq]->aff);
928 	}
929 }
930 
aic_of_ic_init(struct device_node * node,struct device_node * parent)931 static int __init aic_of_ic_init(struct device_node *node, struct device_node *parent)
932 {
933 	int i, die;
934 	u32 off, start_off;
935 	void __iomem *regs;
936 	struct aic_irq_chip *irqc;
937 	struct device_node *affs;
938 	const struct of_device_id *match;
939 
940 	regs = of_iomap(node, 0);
941 	if (WARN_ON(!regs))
942 		return -EIO;
943 
944 	irqc = kzalloc(sizeof(*irqc), GFP_KERNEL);
945 	if (!irqc) {
946 		iounmap(regs);
947 		return -ENOMEM;
948 	}
949 
950 	irqc->base = regs;
951 
952 	match = of_match_node(aic_info_match, node);
953 	if (!match)
954 		goto err_unmap;
955 
956 	irqc->info = *(struct aic_info *)match->data;
957 
958 	aic_irqc = irqc;
959 
960 	switch (irqc->info.version) {
961 	case 1: {
962 		u32 info;
963 
964 		info = aic_ic_read(irqc, AIC_INFO);
965 		irqc->nr_irq = FIELD_GET(AIC_INFO_NR_IRQ, info);
966 		irqc->max_irq = AIC_MAX_IRQ;
967 		irqc->nr_die = irqc->max_die = 1;
968 
969 		off = start_off = irqc->info.target_cpu;
970 		off += sizeof(u32) * irqc->max_irq; /* TARGET_CPU */
971 
972 		irqc->event = irqc->base;
973 
974 		break;
975 	}
976 	case 2: {
977 		u32 info1, info3;
978 
979 		info1 = aic_ic_read(irqc, AIC2_INFO1);
980 		info3 = aic_ic_read(irqc, AIC2_INFO3);
981 
982 		irqc->nr_irq = FIELD_GET(AIC2_INFO1_NR_IRQ, info1);
983 		irqc->max_irq = FIELD_GET(AIC2_INFO3_MAX_IRQ, info3);
984 		irqc->nr_die = FIELD_GET(AIC2_INFO1_LAST_DIE, info1) + 1;
985 		irqc->max_die = FIELD_GET(AIC2_INFO3_MAX_DIE, info3);
986 
987 		off = start_off = irqc->info.irq_cfg;
988 		off += sizeof(u32) * irqc->max_irq; /* IRQ_CFG */
989 
990 		irqc->event = of_iomap(node, 1);
991 		if (WARN_ON(!irqc->event))
992 			goto err_unmap;
993 
994 		break;
995 	}
996 	}
997 
998 	irqc->info.sw_set = off;
999 	off += sizeof(u32) * (irqc->max_irq >> 5); /* SW_SET */
1000 	irqc->info.sw_clr = off;
1001 	off += sizeof(u32) * (irqc->max_irq >> 5); /* SW_CLR */
1002 	irqc->info.mask_set = off;
1003 	off += sizeof(u32) * (irqc->max_irq >> 5); /* MASK_SET */
1004 	irqc->info.mask_clr = off;
1005 	off += sizeof(u32) * (irqc->max_irq >> 5); /* MASK_CLR */
1006 	off += sizeof(u32) * (irqc->max_irq >> 5); /* HW_STATE */
1007 
1008 	if (!irqc->info.fast_ipi)
1009 		static_branch_disable(&use_fast_ipi);
1010 
1011 	if (!irqc->info.local_fast_ipi)
1012 		static_branch_disable(&use_local_fast_ipi);
1013 
1014 	irqc->info.die_stride = off - start_off;
1015 
1016 	irqc->hw_domain = irq_domain_create_tree(of_node_to_fwnode(node),
1017 						 &aic_irq_domain_ops, irqc);
1018 	if (WARN_ON(!irqc->hw_domain))
1019 		goto err_unmap;
1020 
1021 	irq_domain_update_bus_token(irqc->hw_domain, DOMAIN_BUS_WIRED);
1022 
1023 	if (aic_init_smp(irqc, node))
1024 		goto err_remove_domain;
1025 
1026 	affs = of_get_child_by_name(node, "affinities");
1027 	if (affs) {
1028 		struct device_node *chld;
1029 
1030 		for_each_child_of_node(affs, chld)
1031 			build_fiq_affinity(irqc, chld);
1032 	}
1033 	of_node_put(affs);
1034 
1035 	set_handle_irq(aic_handle_irq);
1036 	set_handle_fiq(aic_handle_fiq);
1037 
1038 	off = 0;
1039 	for (die = 0; die < irqc->nr_die; die++) {
1040 		for (i = 0; i < BITS_TO_U32(irqc->nr_irq); i++)
1041 			aic_ic_write(irqc, irqc->info.mask_set + off + i * 4, U32_MAX);
1042 		for (i = 0; i < BITS_TO_U32(irqc->nr_irq); i++)
1043 			aic_ic_write(irqc, irqc->info.sw_clr + off + i * 4, U32_MAX);
1044 		if (irqc->info.target_cpu)
1045 			for (i = 0; i < irqc->nr_irq; i++)
1046 				aic_ic_write(irqc, irqc->info.target_cpu + off + i * 4, 1);
1047 		off += irqc->info.die_stride;
1048 	}
1049 
1050 	if (irqc->info.version == 2) {
1051 		u32 config = aic_ic_read(irqc, AIC2_CONFIG);
1052 
1053 		config |= AIC2_CONFIG_ENABLE;
1054 		aic_ic_write(irqc, AIC2_CONFIG, config);
1055 	}
1056 
1057 	if (!is_kernel_in_hyp_mode())
1058 		pr_info("Kernel running in EL1, mapping interrupts");
1059 
1060 	if (static_branch_likely(&use_fast_ipi))
1061 		pr_info("Using Fast IPIs");
1062 
1063 	cpuhp_setup_state(CPUHP_AP_IRQ_APPLE_AIC_STARTING,
1064 			  "irqchip/apple-aic/ipi:starting",
1065 			  aic_init_cpu, NULL);
1066 
1067 	if (is_kernel_in_hyp_mode()) {
1068 		struct irq_fwspec mi = {
1069 			.fwnode		= of_node_to_fwnode(node),
1070 			.param_count	= 3,
1071 			.param		= {
1072 				[0]	= AIC_FIQ, /* This is a lie */
1073 				[1]	= AIC_VGIC_MI,
1074 				[2]	= IRQ_TYPE_LEVEL_HIGH,
1075 			},
1076 		};
1077 
1078 		vgic_info.maint_irq = irq_create_fwspec_mapping(&mi);
1079 		WARN_ON(!vgic_info.maint_irq);
1080 	}
1081 
1082 	vgic_set_kvm_info(&vgic_info);
1083 
1084 	pr_info("Initialized with %d/%d IRQs * %d/%d die(s), %d FIQs, %d vIPIs",
1085 		irqc->nr_irq, irqc->max_irq, irqc->nr_die, irqc->max_die, AIC_NR_FIQ, AIC_NR_SWIPI);
1086 
1087 	return 0;
1088 
1089 err_remove_domain:
1090 	irq_domain_remove(irqc->hw_domain);
1091 err_unmap:
1092 	if (irqc->event && irqc->event != irqc->base)
1093 		iounmap(irqc->event);
1094 	iounmap(irqc->base);
1095 	kfree(irqc);
1096 	return -ENODEV;
1097 }
1098 
1099 IRQCHIP_DECLARE(apple_aic, "apple,aic", aic_of_ic_init);
1100 IRQCHIP_DECLARE(apple_aic2, "apple,aic2", aic_of_ic_init);
1101