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 static DEFINE_STATIC_KEY_TRUE(use_fast_ipi);
238 
239 struct aic_info {
240 	int version;
241 
242 	/* Register offsets */
243 	u32 event;
244 	u32 target_cpu;
245 	u32 irq_cfg;
246 	u32 sw_set;
247 	u32 sw_clr;
248 	u32 mask_set;
249 	u32 mask_clr;
250 
251 	u32 die_stride;
252 
253 	/* Features */
254 	bool fast_ipi;
255 };
256 
257 static const struct aic_info aic1_info __initconst = {
258 	.version	= 1,
259 
260 	.event		= AIC_EVENT,
261 	.target_cpu	= AIC_TARGET_CPU,
262 };
263 
264 static const struct aic_info aic1_fipi_info __initconst = {
265 	.version	= 1,
266 
267 	.event		= AIC_EVENT,
268 	.target_cpu	= AIC_TARGET_CPU,
269 
270 	.fast_ipi	= true,
271 };
272 
273 static const struct aic_info aic2_info __initconst = {
274 	.version	= 2,
275 
276 	.irq_cfg	= AIC2_IRQ_CFG,
277 
278 	.fast_ipi	= true,
279 };
280 
281 static const struct of_device_id aic_info_match[] = {
282 	{
283 		.compatible = "apple,t8103-aic",
284 		.data = &aic1_fipi_info,
285 	},
286 	{
287 		.compatible = "apple,aic",
288 		.data = &aic1_info,
289 	},
290 	{
291 		.compatible = "apple,aic2",
292 		.data = &aic2_info,
293 	},
294 	{}
295 };
296 
297 struct aic_irq_chip {
298 	void __iomem *base;
299 	void __iomem *event;
300 	struct irq_domain *hw_domain;
301 	struct {
302 		cpumask_t aff;
303 	} *fiq_aff[AIC_NR_FIQ];
304 
305 	int nr_irq;
306 	int max_irq;
307 	int nr_die;
308 	int max_die;
309 
310 	struct aic_info info;
311 };
312 
313 static DEFINE_PER_CPU(uint32_t, aic_fiq_unmasked);
314 
315 static struct aic_irq_chip *aic_irqc;
316 
317 static void aic_handle_ipi(struct pt_regs *regs);
318 
aic_ic_read(struct aic_irq_chip * ic,u32 reg)319 static u32 aic_ic_read(struct aic_irq_chip *ic, u32 reg)
320 {
321 	return readl_relaxed(ic->base + reg);
322 }
323 
aic_ic_write(struct aic_irq_chip * ic,u32 reg,u32 val)324 static void aic_ic_write(struct aic_irq_chip *ic, u32 reg, u32 val)
325 {
326 	writel_relaxed(val, ic->base + reg);
327 }
328 
329 /*
330  * IRQ irqchip
331  */
332 
aic_irq_mask(struct irq_data * d)333 static void aic_irq_mask(struct irq_data *d)
334 {
335 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
336 	struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d);
337 
338 	u32 off = AIC_HWIRQ_DIE(hwirq) * ic->info.die_stride;
339 	u32 irq = AIC_HWIRQ_IRQ(hwirq);
340 
341 	aic_ic_write(ic, ic->info.mask_set + off + MASK_REG(irq), MASK_BIT(irq));
342 }
343 
aic_irq_unmask(struct irq_data * d)344 static void aic_irq_unmask(struct irq_data *d)
345 {
346 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
347 	struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d);
348 
349 	u32 off = AIC_HWIRQ_DIE(hwirq) * ic->info.die_stride;
350 	u32 irq = AIC_HWIRQ_IRQ(hwirq);
351 
352 	aic_ic_write(ic, ic->info.mask_clr + off + MASK_REG(irq), MASK_BIT(irq));
353 }
354 
aic_irq_eoi(struct irq_data * d)355 static void aic_irq_eoi(struct irq_data *d)
356 {
357 	/*
358 	 * Reading the interrupt reason automatically acknowledges and masks
359 	 * the IRQ, so we just unmask it here if needed.
360 	 */
361 	if (!irqd_irq_masked(d))
362 		aic_irq_unmask(d);
363 }
364 
aic_handle_irq(struct pt_regs * regs)365 static void __exception_irq_entry aic_handle_irq(struct pt_regs *regs)
366 {
367 	struct aic_irq_chip *ic = aic_irqc;
368 	u32 event, type, irq;
369 
370 	do {
371 		/*
372 		 * We cannot use a relaxed read here, as reads from DMA buffers
373 		 * need to be ordered after the IRQ fires.
374 		 */
375 		event = readl(ic->event + ic->info.event);
376 		type = FIELD_GET(AIC_EVENT_TYPE, event);
377 		irq = FIELD_GET(AIC_EVENT_NUM, event);
378 
379 		if (type == AIC_EVENT_TYPE_IRQ)
380 			generic_handle_domain_irq(aic_irqc->hw_domain, event);
381 		else if (type == AIC_EVENT_TYPE_IPI && irq == 1)
382 			aic_handle_ipi(regs);
383 		else if (event != 0)
384 			pr_err_ratelimited("Unknown IRQ event %d, %d\n", type, irq);
385 	} while (event);
386 
387 	/*
388 	 * vGIC maintenance interrupts end up here too, so we need to check
389 	 * for them separately. It should however only trigger when NV is
390 	 * in use, and be cleared when coming back from the handler.
391 	 */
392 	if (is_kernel_in_hyp_mode() &&
393 	    (read_sysreg_s(SYS_ICH_HCR_EL2) & ICH_HCR_EN) &&
394 	    read_sysreg_s(SYS_ICH_MISR_EL2) != 0) {
395 		generic_handle_domain_irq(aic_irqc->hw_domain,
396 					  AIC_FIQ_HWIRQ(AIC_VGIC_MI));
397 
398 		if (unlikely((read_sysreg_s(SYS_ICH_HCR_EL2) & ICH_HCR_EN) &&
399 			     read_sysreg_s(SYS_ICH_MISR_EL2))) {
400 			pr_err_ratelimited("vGIC IRQ fired and not handled by KVM, disabling.\n");
401 			sysreg_clear_set_s(SYS_ICH_HCR_EL2, ICH_HCR_EN, 0);
402 		}
403 	}
404 }
405 
aic_irq_set_affinity(struct irq_data * d,const struct cpumask * mask_val,bool force)406 static int aic_irq_set_affinity(struct irq_data *d,
407 				const struct cpumask *mask_val, bool force)
408 {
409 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
410 	struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d);
411 	int cpu;
412 
413 	BUG_ON(!ic->info.target_cpu);
414 
415 	if (force)
416 		cpu = cpumask_first(mask_val);
417 	else
418 		cpu = cpumask_any_and(mask_val, cpu_online_mask);
419 
420 	aic_ic_write(ic, ic->info.target_cpu + AIC_HWIRQ_IRQ(hwirq) * 4, BIT(cpu));
421 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
422 
423 	return IRQ_SET_MASK_OK;
424 }
425 
aic_irq_set_type(struct irq_data * d,unsigned int type)426 static int aic_irq_set_type(struct irq_data *d, unsigned int type)
427 {
428 	/*
429 	 * Some IRQs (e.g. MSIs) implicitly have edge semantics, and we don't
430 	 * have a way to find out the type of any given IRQ, so just allow both.
431 	 */
432 	return (type == IRQ_TYPE_LEVEL_HIGH || type == IRQ_TYPE_EDGE_RISING) ? 0 : -EINVAL;
433 }
434 
435 static struct irq_chip aic_chip = {
436 	.name = "AIC",
437 	.irq_mask = aic_irq_mask,
438 	.irq_unmask = aic_irq_unmask,
439 	.irq_eoi = aic_irq_eoi,
440 	.irq_set_affinity = aic_irq_set_affinity,
441 	.irq_set_type = aic_irq_set_type,
442 };
443 
444 static struct irq_chip aic2_chip = {
445 	.name = "AIC2",
446 	.irq_mask = aic_irq_mask,
447 	.irq_unmask = aic_irq_unmask,
448 	.irq_eoi = aic_irq_eoi,
449 	.irq_set_type = aic_irq_set_type,
450 };
451 
452 /*
453  * FIQ irqchip
454  */
455 
aic_fiq_get_idx(struct irq_data * d)456 static unsigned long aic_fiq_get_idx(struct irq_data *d)
457 {
458 	return AIC_HWIRQ_IRQ(irqd_to_hwirq(d));
459 }
460 
aic_fiq_set_mask(struct irq_data * d)461 static void aic_fiq_set_mask(struct irq_data *d)
462 {
463 	/* Only the guest timers have real mask bits, unfortunately. */
464 	switch (aic_fiq_get_idx(d)) {
465 	case AIC_TMR_EL02_PHYS:
466 		sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, VM_TMR_FIQ_ENABLE_P, 0);
467 		isb();
468 		break;
469 	case AIC_TMR_EL02_VIRT:
470 		sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, VM_TMR_FIQ_ENABLE_V, 0);
471 		isb();
472 		break;
473 	default:
474 		break;
475 	}
476 }
477 
aic_fiq_clear_mask(struct irq_data * d)478 static void aic_fiq_clear_mask(struct irq_data *d)
479 {
480 	switch (aic_fiq_get_idx(d)) {
481 	case AIC_TMR_EL02_PHYS:
482 		sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, 0, VM_TMR_FIQ_ENABLE_P);
483 		isb();
484 		break;
485 	case AIC_TMR_EL02_VIRT:
486 		sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, 0, VM_TMR_FIQ_ENABLE_V);
487 		isb();
488 		break;
489 	default:
490 		break;
491 	}
492 }
493 
aic_fiq_mask(struct irq_data * d)494 static void aic_fiq_mask(struct irq_data *d)
495 {
496 	aic_fiq_set_mask(d);
497 	__this_cpu_and(aic_fiq_unmasked, ~BIT(aic_fiq_get_idx(d)));
498 }
499 
aic_fiq_unmask(struct irq_data * d)500 static void aic_fiq_unmask(struct irq_data *d)
501 {
502 	aic_fiq_clear_mask(d);
503 	__this_cpu_or(aic_fiq_unmasked, BIT(aic_fiq_get_idx(d)));
504 }
505 
aic_fiq_eoi(struct irq_data * d)506 static void aic_fiq_eoi(struct irq_data *d)
507 {
508 	/* We mask to ack (where we can), so we need to unmask at EOI. */
509 	if (__this_cpu_read(aic_fiq_unmasked) & BIT(aic_fiq_get_idx(d)))
510 		aic_fiq_clear_mask(d);
511 }
512 
513 #define TIMER_FIRING(x)                                                        \
514 	(((x) & (ARCH_TIMER_CTRL_ENABLE | ARCH_TIMER_CTRL_IT_MASK |            \
515 		 ARCH_TIMER_CTRL_IT_STAT)) ==                                  \
516 	 (ARCH_TIMER_CTRL_ENABLE | ARCH_TIMER_CTRL_IT_STAT))
517 
aic_handle_fiq(struct pt_regs * regs)518 static void __exception_irq_entry aic_handle_fiq(struct pt_regs *regs)
519 {
520 	/*
521 	 * It would be really nice if we had a system register that lets us get
522 	 * the FIQ source state without having to peek down into sources...
523 	 * but such a register does not seem to exist.
524 	 *
525 	 * So, we have these potential sources to test for:
526 	 *  - Fast IPIs (not yet used)
527 	 *  - The 4 timers (CNTP, CNTV for each of HV and guest)
528 	 *  - Per-core PMCs (not yet supported)
529 	 *  - Per-cluster uncore PMCs (not yet supported)
530 	 *
531 	 * Since not dealing with any of these results in a FIQ storm,
532 	 * we check for everything here, even things we don't support yet.
533 	 */
534 
535 	if (read_sysreg_s(SYS_IMP_APL_IPI_SR_EL1) & IPI_SR_PENDING) {
536 		if (static_branch_likely(&use_fast_ipi)) {
537 			aic_handle_ipi(regs);
538 		} else {
539 			pr_err_ratelimited("Fast IPI fired. Acking.\n");
540 			write_sysreg_s(IPI_SR_PENDING, SYS_IMP_APL_IPI_SR_EL1);
541 		}
542 	}
543 
544 	if (TIMER_FIRING(read_sysreg(cntp_ctl_el0)))
545 		generic_handle_domain_irq(aic_irqc->hw_domain,
546 					  AIC_FIQ_HWIRQ(AIC_TMR_EL0_PHYS));
547 
548 	if (TIMER_FIRING(read_sysreg(cntv_ctl_el0)))
549 		generic_handle_domain_irq(aic_irqc->hw_domain,
550 					  AIC_FIQ_HWIRQ(AIC_TMR_EL0_VIRT));
551 
552 	if (is_kernel_in_hyp_mode()) {
553 		uint64_t enabled = read_sysreg_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2);
554 
555 		if ((enabled & VM_TMR_FIQ_ENABLE_P) &&
556 		    TIMER_FIRING(read_sysreg_s(SYS_CNTP_CTL_EL02)))
557 			generic_handle_domain_irq(aic_irqc->hw_domain,
558 						  AIC_FIQ_HWIRQ(AIC_TMR_EL02_PHYS));
559 
560 		if ((enabled & VM_TMR_FIQ_ENABLE_V) &&
561 		    TIMER_FIRING(read_sysreg_s(SYS_CNTV_CTL_EL02)))
562 			generic_handle_domain_irq(aic_irqc->hw_domain,
563 						  AIC_FIQ_HWIRQ(AIC_TMR_EL02_VIRT));
564 	}
565 
566 	if (read_sysreg_s(SYS_IMP_APL_PMCR0_EL1) & PMCR0_IACT) {
567 		int irq;
568 		if (cpumask_test_cpu(smp_processor_id(),
569 				     &aic_irqc->fiq_aff[AIC_CPU_PMU_P]->aff))
570 			irq = AIC_CPU_PMU_P;
571 		else
572 			irq = AIC_CPU_PMU_E;
573 		generic_handle_domain_irq(aic_irqc->hw_domain,
574 					  AIC_FIQ_HWIRQ(irq));
575 	}
576 
577 	if (FIELD_GET(UPMCR0_IMODE, read_sysreg_s(SYS_IMP_APL_UPMCR0_EL1)) == UPMCR0_IMODE_FIQ &&
578 			(read_sysreg_s(SYS_IMP_APL_UPMSR_EL1) & UPMSR_IACT)) {
579 		/* Same story with uncore PMCs */
580 		pr_err_ratelimited("Uncore PMC FIQ fired. Masking.\n");
581 		sysreg_clear_set_s(SYS_IMP_APL_UPMCR0_EL1, UPMCR0_IMODE,
582 				   FIELD_PREP(UPMCR0_IMODE, UPMCR0_IMODE_OFF));
583 	}
584 }
585 
aic_fiq_set_type(struct irq_data * d,unsigned int type)586 static int aic_fiq_set_type(struct irq_data *d, unsigned int type)
587 {
588 	return (type == IRQ_TYPE_LEVEL_HIGH) ? 0 : -EINVAL;
589 }
590 
591 static struct irq_chip fiq_chip = {
592 	.name = "AIC-FIQ",
593 	.irq_mask = aic_fiq_mask,
594 	.irq_unmask = aic_fiq_unmask,
595 	.irq_ack = aic_fiq_set_mask,
596 	.irq_eoi = aic_fiq_eoi,
597 	.irq_set_type = aic_fiq_set_type,
598 };
599 
600 /*
601  * Main IRQ domain
602  */
603 
aic_irq_domain_map(struct irq_domain * id,unsigned int irq,irq_hw_number_t hw)604 static int aic_irq_domain_map(struct irq_domain *id, unsigned int irq,
605 			      irq_hw_number_t hw)
606 {
607 	struct aic_irq_chip *ic = id->host_data;
608 	u32 type = FIELD_GET(AIC_EVENT_TYPE, hw);
609 	struct irq_chip *chip = &aic_chip;
610 
611 	if (ic->info.version == 2)
612 		chip = &aic2_chip;
613 
614 	if (type == AIC_EVENT_TYPE_IRQ) {
615 		irq_domain_set_info(id, irq, hw, chip, id->host_data,
616 				    handle_fasteoi_irq, NULL, NULL);
617 		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(irq)));
618 	} else {
619 		int fiq = FIELD_GET(AIC_EVENT_NUM, hw);
620 
621 		switch (fiq) {
622 		case AIC_CPU_PMU_P:
623 		case AIC_CPU_PMU_E:
624 			irq_set_percpu_devid_partition(irq, &ic->fiq_aff[fiq]->aff);
625 			break;
626 		default:
627 			irq_set_percpu_devid(irq);
628 			break;
629 		}
630 
631 		irq_domain_set_info(id, irq, hw, &fiq_chip, id->host_data,
632 				    handle_percpu_devid_irq, NULL, NULL);
633 	}
634 
635 	return 0;
636 }
637 
aic_irq_domain_translate(struct irq_domain * id,struct irq_fwspec * fwspec,unsigned long * hwirq,unsigned int * type)638 static int aic_irq_domain_translate(struct irq_domain *id,
639 				    struct irq_fwspec *fwspec,
640 				    unsigned long *hwirq,
641 				    unsigned int *type)
642 {
643 	struct aic_irq_chip *ic = id->host_data;
644 	u32 *args;
645 	u32 die = 0;
646 
647 	if (fwspec->param_count < 3 || fwspec->param_count > 4 ||
648 	    !is_of_node(fwspec->fwnode))
649 		return -EINVAL;
650 
651 	args = &fwspec->param[1];
652 
653 	if (fwspec->param_count == 4) {
654 		die = args[0];
655 		args++;
656 	}
657 
658 	switch (fwspec->param[0]) {
659 	case AIC_IRQ:
660 		if (die >= ic->nr_die)
661 			return -EINVAL;
662 		if (args[0] >= ic->nr_irq)
663 			return -EINVAL;
664 		*hwirq = AIC_IRQ_HWIRQ(die, args[0]);
665 		break;
666 	case AIC_FIQ:
667 		if (die != 0)
668 			return -EINVAL;
669 		if (args[0] >= AIC_NR_FIQ)
670 			return -EINVAL;
671 		*hwirq = AIC_FIQ_HWIRQ(args[0]);
672 
673 		/*
674 		 * In EL1 the non-redirected registers are the guest's,
675 		 * not EL2's, so remap the hwirqs to match.
676 		 */
677 		if (!is_kernel_in_hyp_mode()) {
678 			switch (args[0]) {
679 			case AIC_TMR_GUEST_PHYS:
680 				*hwirq = AIC_FIQ_HWIRQ(AIC_TMR_EL0_PHYS);
681 				break;
682 			case AIC_TMR_GUEST_VIRT:
683 				*hwirq = AIC_FIQ_HWIRQ(AIC_TMR_EL0_VIRT);
684 				break;
685 			case AIC_TMR_HV_PHYS:
686 			case AIC_TMR_HV_VIRT:
687 				return -ENOENT;
688 			default:
689 				break;
690 			}
691 		}
692 		break;
693 	default:
694 		return -EINVAL;
695 	}
696 
697 	*type = args[1] & IRQ_TYPE_SENSE_MASK;
698 
699 	return 0;
700 }
701 
aic_irq_domain_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * arg)702 static int aic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
703 				unsigned int nr_irqs, void *arg)
704 {
705 	unsigned int type = IRQ_TYPE_NONE;
706 	struct irq_fwspec *fwspec = arg;
707 	irq_hw_number_t hwirq;
708 	int i, ret;
709 
710 	ret = aic_irq_domain_translate(domain, fwspec, &hwirq, &type);
711 	if (ret)
712 		return ret;
713 
714 	for (i = 0; i < nr_irqs; i++) {
715 		ret = aic_irq_domain_map(domain, virq + i, hwirq + i);
716 		if (ret)
717 			return ret;
718 	}
719 
720 	return 0;
721 }
722 
aic_irq_domain_free(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs)723 static void aic_irq_domain_free(struct irq_domain *domain, unsigned int virq,
724 				unsigned int nr_irqs)
725 {
726 	int i;
727 
728 	for (i = 0; i < nr_irqs; i++) {
729 		struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
730 
731 		irq_set_handler(virq + i, NULL);
732 		irq_domain_reset_irq_data(d);
733 	}
734 }
735 
736 static const struct irq_domain_ops aic_irq_domain_ops = {
737 	.translate	= aic_irq_domain_translate,
738 	.alloc		= aic_irq_domain_alloc,
739 	.free		= aic_irq_domain_free,
740 };
741 
742 /*
743  * IPI irqchip
744  */
745 
aic_ipi_send_fast(int cpu)746 static void aic_ipi_send_fast(int cpu)
747 {
748 	u64 mpidr = cpu_logical_map(cpu);
749 	u64 my_mpidr = read_cpuid_mpidr();
750 	u64 cluster = MPIDR_CLUSTER(mpidr);
751 	u64 idx = MPIDR_CPU(mpidr);
752 
753 	if (MPIDR_CLUSTER(my_mpidr) == cluster)
754 		write_sysreg_s(FIELD_PREP(IPI_RR_CPU, idx),
755 			       SYS_IMP_APL_IPI_RR_LOCAL_EL1);
756 	else
757 		write_sysreg_s(FIELD_PREP(IPI_RR_CPU, idx) | FIELD_PREP(IPI_RR_CLUSTER, cluster),
758 			       SYS_IMP_APL_IPI_RR_GLOBAL_EL1);
759 	isb();
760 }
761 
aic_handle_ipi(struct pt_regs * regs)762 static void aic_handle_ipi(struct pt_regs *regs)
763 {
764 	/*
765 	 * Ack the IPI. We need to order this after the AIC event read, but
766 	 * that is enforced by normal MMIO ordering guarantees.
767 	 *
768 	 * For the Fast IPI case, this needs to be ordered before the vIPI
769 	 * handling below, so we need to isb();
770 	 */
771 	if (static_branch_likely(&use_fast_ipi)) {
772 		write_sysreg_s(IPI_SR_PENDING, SYS_IMP_APL_IPI_SR_EL1);
773 		isb();
774 	} else {
775 		aic_ic_write(aic_irqc, AIC_IPI_ACK, AIC_IPI_OTHER);
776 	}
777 
778 	ipi_mux_process();
779 
780 	/*
781 	 * No ordering needed here; at worst this just changes the timing of
782 	 * when the next IPI will be delivered.
783 	 */
784 	if (!static_branch_likely(&use_fast_ipi))
785 		aic_ic_write(aic_irqc, AIC_IPI_MASK_CLR, AIC_IPI_OTHER);
786 }
787 
aic_ipi_send_single(unsigned int cpu)788 static void aic_ipi_send_single(unsigned int cpu)
789 {
790 	if (static_branch_likely(&use_fast_ipi))
791 		aic_ipi_send_fast(cpu);
792 	else
793 		aic_ic_write(aic_irqc, AIC_IPI_SEND, AIC_IPI_SEND_CPU(cpu));
794 }
795 
aic_init_smp(struct aic_irq_chip * irqc,struct device_node * node)796 static int __init aic_init_smp(struct aic_irq_chip *irqc, struct device_node *node)
797 {
798 	int base_ipi;
799 
800 	base_ipi = ipi_mux_create(AIC_NR_SWIPI, aic_ipi_send_single);
801 	if (WARN_ON(base_ipi <= 0))
802 		return -ENODEV;
803 
804 	set_smp_ipi_range(base_ipi, AIC_NR_SWIPI);
805 
806 	return 0;
807 }
808 
aic_init_cpu(unsigned int cpu)809 static int aic_init_cpu(unsigned int cpu)
810 {
811 	/* Mask all hard-wired per-CPU IRQ/FIQ sources */
812 
813 	/* Pending Fast IPI FIQs */
814 	write_sysreg_s(IPI_SR_PENDING, SYS_IMP_APL_IPI_SR_EL1);
815 
816 	/* Timer FIQs */
817 	sysreg_clear_set(cntp_ctl_el0, 0, ARCH_TIMER_CTRL_IT_MASK);
818 	sysreg_clear_set(cntv_ctl_el0, 0, ARCH_TIMER_CTRL_IT_MASK);
819 
820 	/* EL2-only (VHE mode) IRQ sources */
821 	if (is_kernel_in_hyp_mode()) {
822 		/* Guest timers */
823 		sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2,
824 				   VM_TMR_FIQ_ENABLE_V | VM_TMR_FIQ_ENABLE_P, 0);
825 
826 		/* vGIC maintenance IRQ */
827 		sysreg_clear_set_s(SYS_ICH_HCR_EL2, ICH_HCR_EN, 0);
828 	}
829 
830 	/* PMC FIQ */
831 	sysreg_clear_set_s(SYS_IMP_APL_PMCR0_EL1, PMCR0_IMODE | PMCR0_IACT,
832 			   FIELD_PREP(PMCR0_IMODE, PMCR0_IMODE_OFF));
833 
834 	/* Uncore PMC FIQ */
835 	sysreg_clear_set_s(SYS_IMP_APL_UPMCR0_EL1, UPMCR0_IMODE,
836 			   FIELD_PREP(UPMCR0_IMODE, UPMCR0_IMODE_OFF));
837 
838 	/* Commit all of the above */
839 	isb();
840 
841 	if (aic_irqc->info.version == 1) {
842 		/*
843 		 * Make sure the kernel's idea of logical CPU order is the same as AIC's
844 		 * If we ever end up with a mismatch here, we will have to introduce
845 		 * a mapping table similar to what other irqchip drivers do.
846 		 */
847 		WARN_ON(aic_ic_read(aic_irqc, AIC_WHOAMI) != smp_processor_id());
848 
849 		/*
850 		 * Always keep IPIs unmasked at the hardware level (except auto-masking
851 		 * by AIC during processing). We manage masks at the vIPI level.
852 		 * These registers only exist on AICv1, AICv2 always uses fast IPIs.
853 		 */
854 		aic_ic_write(aic_irqc, AIC_IPI_ACK, AIC_IPI_SELF | AIC_IPI_OTHER);
855 		if (static_branch_likely(&use_fast_ipi)) {
856 			aic_ic_write(aic_irqc, AIC_IPI_MASK_SET, AIC_IPI_SELF | AIC_IPI_OTHER);
857 		} else {
858 			aic_ic_write(aic_irqc, AIC_IPI_MASK_SET, AIC_IPI_SELF);
859 			aic_ic_write(aic_irqc, AIC_IPI_MASK_CLR, AIC_IPI_OTHER);
860 		}
861 	}
862 
863 	/* Initialize the local mask state */
864 	__this_cpu_write(aic_fiq_unmasked, 0);
865 
866 	return 0;
867 }
868 
869 static struct gic_kvm_info vgic_info __initdata = {
870 	.type			= GIC_V3,
871 	.no_maint_irq_mask	= true,
872 	.no_hw_deactivation	= true,
873 };
874 
build_fiq_affinity(struct aic_irq_chip * ic,struct device_node * aff)875 static void build_fiq_affinity(struct aic_irq_chip *ic, struct device_node *aff)
876 {
877 	int i, n;
878 	u32 fiq;
879 
880 	if (of_property_read_u32(aff, "apple,fiq-index", &fiq) ||
881 	    WARN_ON(fiq >= AIC_NR_FIQ) || ic->fiq_aff[fiq])
882 		return;
883 
884 	n = of_property_count_elems_of_size(aff, "cpus", sizeof(u32));
885 	if (WARN_ON(n < 0))
886 		return;
887 
888 	ic->fiq_aff[fiq] = kzalloc(sizeof(*ic->fiq_aff[fiq]), GFP_KERNEL);
889 	if (!ic->fiq_aff[fiq])
890 		return;
891 
892 	for (i = 0; i < n; i++) {
893 		struct device_node *cpu_node;
894 		u32 cpu_phandle;
895 		int cpu;
896 
897 		if (of_property_read_u32_index(aff, "cpus", i, &cpu_phandle))
898 			continue;
899 
900 		cpu_node = of_find_node_by_phandle(cpu_phandle);
901 		if (WARN_ON(!cpu_node))
902 			continue;
903 
904 		cpu = of_cpu_node_to_id(cpu_node);
905 		of_node_put(cpu_node);
906 		if (WARN_ON(cpu < 0))
907 			continue;
908 
909 		cpumask_set_cpu(cpu, &ic->fiq_aff[fiq]->aff);
910 	}
911 }
912 
aic_of_ic_init(struct device_node * node,struct device_node * parent)913 static int __init aic_of_ic_init(struct device_node *node, struct device_node *parent)
914 {
915 	int i, die;
916 	u32 off, start_off;
917 	void __iomem *regs;
918 	struct aic_irq_chip *irqc;
919 	struct device_node *affs;
920 	const struct of_device_id *match;
921 
922 	regs = of_iomap(node, 0);
923 	if (WARN_ON(!regs))
924 		return -EIO;
925 
926 	irqc = kzalloc(sizeof(*irqc), GFP_KERNEL);
927 	if (!irqc) {
928 		iounmap(regs);
929 		return -ENOMEM;
930 	}
931 
932 	irqc->base = regs;
933 
934 	match = of_match_node(aic_info_match, node);
935 	if (!match)
936 		goto err_unmap;
937 
938 	irqc->info = *(struct aic_info *)match->data;
939 
940 	aic_irqc = irqc;
941 
942 	switch (irqc->info.version) {
943 	case 1: {
944 		u32 info;
945 
946 		info = aic_ic_read(irqc, AIC_INFO);
947 		irqc->nr_irq = FIELD_GET(AIC_INFO_NR_IRQ, info);
948 		irqc->max_irq = AIC_MAX_IRQ;
949 		irqc->nr_die = irqc->max_die = 1;
950 
951 		off = start_off = irqc->info.target_cpu;
952 		off += sizeof(u32) * irqc->max_irq; /* TARGET_CPU */
953 
954 		irqc->event = irqc->base;
955 
956 		break;
957 	}
958 	case 2: {
959 		u32 info1, info3;
960 
961 		info1 = aic_ic_read(irqc, AIC2_INFO1);
962 		info3 = aic_ic_read(irqc, AIC2_INFO3);
963 
964 		irqc->nr_irq = FIELD_GET(AIC2_INFO1_NR_IRQ, info1);
965 		irqc->max_irq = FIELD_GET(AIC2_INFO3_MAX_IRQ, info3);
966 		irqc->nr_die = FIELD_GET(AIC2_INFO1_LAST_DIE, info1) + 1;
967 		irqc->max_die = FIELD_GET(AIC2_INFO3_MAX_DIE, info3);
968 
969 		off = start_off = irqc->info.irq_cfg;
970 		off += sizeof(u32) * irqc->max_irq; /* IRQ_CFG */
971 
972 		irqc->event = of_iomap(node, 1);
973 		if (WARN_ON(!irqc->event))
974 			goto err_unmap;
975 
976 		break;
977 	}
978 	}
979 
980 	irqc->info.sw_set = off;
981 	off += sizeof(u32) * (irqc->max_irq >> 5); /* SW_SET */
982 	irqc->info.sw_clr = off;
983 	off += sizeof(u32) * (irqc->max_irq >> 5); /* SW_CLR */
984 	irqc->info.mask_set = off;
985 	off += sizeof(u32) * (irqc->max_irq >> 5); /* MASK_SET */
986 	irqc->info.mask_clr = off;
987 	off += sizeof(u32) * (irqc->max_irq >> 5); /* MASK_CLR */
988 	off += sizeof(u32) * (irqc->max_irq >> 5); /* HW_STATE */
989 
990 	if (irqc->info.fast_ipi)
991 		static_branch_enable(&use_fast_ipi);
992 	else
993 		static_branch_disable(&use_fast_ipi);
994 
995 	irqc->info.die_stride = off - start_off;
996 
997 	irqc->hw_domain = irq_domain_create_tree(of_node_to_fwnode(node),
998 						 &aic_irq_domain_ops, irqc);
999 	if (WARN_ON(!irqc->hw_domain))
1000 		goto err_unmap;
1001 
1002 	irq_domain_update_bus_token(irqc->hw_domain, DOMAIN_BUS_WIRED);
1003 
1004 	if (aic_init_smp(irqc, node))
1005 		goto err_remove_domain;
1006 
1007 	affs = of_get_child_by_name(node, "affinities");
1008 	if (affs) {
1009 		struct device_node *chld;
1010 
1011 		for_each_child_of_node(affs, chld)
1012 			build_fiq_affinity(irqc, chld);
1013 	}
1014 	of_node_put(affs);
1015 
1016 	set_handle_irq(aic_handle_irq);
1017 	set_handle_fiq(aic_handle_fiq);
1018 
1019 	off = 0;
1020 	for (die = 0; die < irqc->nr_die; die++) {
1021 		for (i = 0; i < BITS_TO_U32(irqc->nr_irq); i++)
1022 			aic_ic_write(irqc, irqc->info.mask_set + off + i * 4, U32_MAX);
1023 		for (i = 0; i < BITS_TO_U32(irqc->nr_irq); i++)
1024 			aic_ic_write(irqc, irqc->info.sw_clr + off + i * 4, U32_MAX);
1025 		if (irqc->info.target_cpu)
1026 			for (i = 0; i < irqc->nr_irq; i++)
1027 				aic_ic_write(irqc, irqc->info.target_cpu + off + i * 4, 1);
1028 		off += irqc->info.die_stride;
1029 	}
1030 
1031 	if (irqc->info.version == 2) {
1032 		u32 config = aic_ic_read(irqc, AIC2_CONFIG);
1033 
1034 		config |= AIC2_CONFIG_ENABLE;
1035 		aic_ic_write(irqc, AIC2_CONFIG, config);
1036 	}
1037 
1038 	if (!is_kernel_in_hyp_mode())
1039 		pr_info("Kernel running in EL1, mapping interrupts");
1040 
1041 	if (static_branch_likely(&use_fast_ipi))
1042 		pr_info("Using Fast IPIs");
1043 
1044 	cpuhp_setup_state(CPUHP_AP_IRQ_APPLE_AIC_STARTING,
1045 			  "irqchip/apple-aic/ipi:starting",
1046 			  aic_init_cpu, NULL);
1047 
1048 	if (is_kernel_in_hyp_mode()) {
1049 		struct irq_fwspec mi = {
1050 			.fwnode		= of_node_to_fwnode(node),
1051 			.param_count	= 3,
1052 			.param		= {
1053 				[0]	= AIC_FIQ, /* This is a lie */
1054 				[1]	= AIC_VGIC_MI,
1055 				[2]	= IRQ_TYPE_LEVEL_HIGH,
1056 			},
1057 		};
1058 
1059 		vgic_info.maint_irq = irq_create_fwspec_mapping(&mi);
1060 		WARN_ON(!vgic_info.maint_irq);
1061 	}
1062 
1063 	vgic_set_kvm_info(&vgic_info);
1064 
1065 	pr_info("Initialized with %d/%d IRQs * %d/%d die(s), %d FIQs, %d vIPIs",
1066 		irqc->nr_irq, irqc->max_irq, irqc->nr_die, irqc->max_die, AIC_NR_FIQ, AIC_NR_SWIPI);
1067 
1068 	return 0;
1069 
1070 err_remove_domain:
1071 	irq_domain_remove(irqc->hw_domain);
1072 err_unmap:
1073 	if (irqc->event && irqc->event != irqc->base)
1074 		iounmap(irqc->event);
1075 	iounmap(irqc->base);
1076 	kfree(irqc);
1077 	return -ENODEV;
1078 }
1079 
1080 IRQCHIP_DECLARE(apple_aic, "apple,aic", aic_of_ic_init);
1081 IRQCHIP_DECLARE(apple_aic2, "apple,aic2", aic_of_ic_init);
1082