2 * Copyright (C) 2013, 2014 ARM Limited, All Rights Reserved.
3 * Author: Marc Zyngier <marc.zyngier@arm.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 #include <linux/cpu.h>
19 #include <linux/delay.h>
20 #include <linux/interrupt.h>
22 #include <linux/of_address.h>
23 #include <linux/of_irq.h>
24 #include <linux/percpu.h>
25 #include <linux/slab.h>
27 #include <linux/irqchip/arm-gic-v3.h>
29 #include <asm/cputype.h>
30 #include <asm/exception.h>
31 #include <asm/smp_plat.h>
33 #include "irq-gic-common.h"
36 struct gic_chip_data {
37 void __iomem *dist_base;
38 void __iomem **redist_base;
39 void __percpu __iomem **rdist;
40 struct irq_domain *domain;
46 static struct gic_chip_data gic_data __read_mostly;
48 #define gic_data_rdist() (this_cpu_ptr(gic_data.rdist))
49 #define gic_data_rdist_rd_base() (*gic_data_rdist())
50 #define gic_data_rdist_sgi_base() (gic_data_rdist_rd_base() + SZ_64K)
52 /* Our default, arbitrary priority value. Linux only uses one anyway. */
53 #define DEFAULT_PMR_VALUE 0xf0
55 static inline unsigned int gic_irq(struct irq_data *d)
60 static inline int gic_irq_in_rdist(struct irq_data *d)
62 return gic_irq(d) < 32;
65 static inline void __iomem *gic_dist_base(struct irq_data *d)
67 if (gic_irq_in_rdist(d)) /* SGI+PPI -> SGI_base for this CPU */
68 return gic_data_rdist_sgi_base();
70 if (d->hwirq <= 1023) /* SPI -> dist_base */
71 return gic_data.dist_base;
74 BUG(); /* LPI Detected!!! */
79 static void gic_do_wait_for_rwp(void __iomem *base)
81 u32 count = 1000000; /* 1s! */
83 while (readl_relaxed(base + GICD_CTLR) & GICD_CTLR_RWP) {
86 pr_err_ratelimited("RWP timeout, gone fishing\n");
94 /* Wait for completion of a distributor change */
95 static void gic_dist_wait_for_rwp(void)
97 gic_do_wait_for_rwp(gic_data.dist_base);
100 /* Wait for completion of a redistributor change */
101 static void gic_redist_wait_for_rwp(void)
103 gic_do_wait_for_rwp(gic_data_rdist_rd_base());
106 /* Low level accessors */
107 static u64 gic_read_iar(void)
111 asm volatile("mrs_s %0, " __stringify(ICC_IAR1_EL1) : "=r" (irqstat));
115 static void gic_write_pmr(u64 val)
117 asm volatile("msr_s " __stringify(ICC_PMR_EL1) ", %0" : : "r" (val));
120 static void gic_write_ctlr(u64 val)
122 asm volatile("msr_s " __stringify(ICC_CTLR_EL1) ", %0" : : "r" (val));
126 static void gic_write_grpen1(u64 val)
128 asm volatile("msr_s " __stringify(ICC_GRPEN1_EL1) ", %0" : : "r" (val));
132 static void gic_write_sgi1r(u64 val)
134 asm volatile("msr_s " __stringify(ICC_SGI1R_EL1) ", %0" : : "r" (val));
137 static void gic_enable_sre(void)
141 asm volatile("mrs_s %0, " __stringify(ICC_SRE_EL1) : "=r" (val));
142 val |= ICC_SRE_EL1_SRE;
143 asm volatile("msr_s " __stringify(ICC_SRE_EL1) ", %0" : : "r" (val));
147 * Need to check that the SRE bit has actually been set. If
148 * not, it means that SRE is disabled at EL2. We're going to
149 * die painfully, and there is nothing we can do about it.
151 * Kindly inform the luser.
153 asm volatile("mrs_s %0, " __stringify(ICC_SRE_EL1) : "=r" (val));
154 if (!(val & ICC_SRE_EL1_SRE))
155 pr_err("GIC: unable to set SRE (disabled at EL2), panic ahead\n");
158 static void gic_enable_redist(void)
161 u32 count = 1000000; /* 1s! */
164 rbase = gic_data_rdist_rd_base();
166 /* Wake up this CPU redistributor */
167 val = readl_relaxed(rbase + GICR_WAKER);
168 val &= ~GICR_WAKER_ProcessorSleep;
169 writel_relaxed(val, rbase + GICR_WAKER);
171 while (readl_relaxed(rbase + GICR_WAKER) & GICR_WAKER_ChildrenAsleep) {
174 pr_err_ratelimited("redist didn't wake up...\n");
183 * Routines to disable, enable, EOI and route interrupts
185 static void gic_poke_irq(struct irq_data *d, u32 offset)
187 u32 mask = 1 << (gic_irq(d) % 32);
188 void (*rwp_wait)(void);
191 if (gic_irq_in_rdist(d)) {
192 base = gic_data_rdist_sgi_base();
193 rwp_wait = gic_redist_wait_for_rwp;
195 base = gic_data.dist_base;
196 rwp_wait = gic_dist_wait_for_rwp;
199 writel_relaxed(mask, base + offset + (gic_irq(d) / 32) * 4);
203 static int gic_peek_irq(struct irq_data *d, u32 offset)
205 u32 mask = 1 << (gic_irq(d) % 32);
208 if (gic_irq_in_rdist(d))
209 base = gic_data_rdist_sgi_base();
211 base = gic_data.dist_base;
213 return !!(readl_relaxed(base + offset + (gic_irq(d) / 32) * 4) & mask);
216 static void gic_mask_irq(struct irq_data *d)
218 gic_poke_irq(d, GICD_ICENABLER);
221 static void gic_unmask_irq(struct irq_data *d)
223 gic_poke_irq(d, GICD_ISENABLER);
226 static void gic_eoi_irq(struct irq_data *d)
228 gic_write_eoir(gic_irq(d));
231 static int gic_set_type(struct irq_data *d, unsigned int type)
233 unsigned int irq = gic_irq(d);
234 void (*rwp_wait)(void);
237 /* Interrupt configuration for SGIs can't be changed */
241 if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
244 if (gic_irq_in_rdist(d)) {
245 base = gic_data_rdist_sgi_base();
246 rwp_wait = gic_redist_wait_for_rwp;
248 base = gic_data.dist_base;
249 rwp_wait = gic_dist_wait_for_rwp;
252 gic_configure_irq(irq, type, base, rwp_wait);
257 static u64 gic_mpidr_to_affinity(u64 mpidr)
261 aff = (MPIDR_AFFINITY_LEVEL(mpidr, 3) << 32 |
262 MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
263 MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8 |
264 MPIDR_AFFINITY_LEVEL(mpidr, 0));
269 static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
274 irqnr = gic_read_iar();
276 if (likely(irqnr > 15 && irqnr < 1020)) {
277 u64 irq = irq_find_mapping(gic_data.domain, irqnr);
279 handle_IRQ(irq, regs);
283 WARN_ONCE(true, "Unexpected SPI received!\n");
284 gic_write_eoir(irqnr);
287 gic_write_eoir(irqnr);
289 handle_IPI(irqnr, regs);
291 WARN_ONCE(true, "Unexpected SGI received!\n");
295 } while (irqnr != ICC_IAR1_EL1_SPURIOUS);
298 static void __init gic_dist_init(void)
302 void __iomem *base = gic_data.dist_base;
304 /* Disable the distributor */
305 writel_relaxed(0, base + GICD_CTLR);
306 gic_dist_wait_for_rwp();
308 gic_dist_config(base, gic_data.irq_nr, gic_dist_wait_for_rwp);
310 /* Enable distributor with ARE, Group1 */
311 writel_relaxed(GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G1A | GICD_CTLR_ENABLE_G1,
315 * Set all global interrupts to the boot CPU only. ARE must be
318 affinity = gic_mpidr_to_affinity(cpu_logical_map(smp_processor_id()));
319 for (i = 32; i < gic_data.irq_nr; i++)
320 writeq_relaxed(affinity, base + GICD_IROUTER + i * 8);
323 static int gic_populate_rdist(void)
325 u64 mpidr = cpu_logical_map(smp_processor_id());
331 * Convert affinity to a 32bit value that can be matched to
332 * GICR_TYPER bits [63:32].
334 aff = (MPIDR_AFFINITY_LEVEL(mpidr, 3) << 24 |
335 MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
336 MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8 |
337 MPIDR_AFFINITY_LEVEL(mpidr, 0));
339 for (i = 0; i < gic_data.redist_regions; i++) {
340 void __iomem *ptr = gic_data.redist_base[i];
343 reg = readl_relaxed(ptr + GICR_PIDR2) & GIC_PIDR2_ARCH_MASK;
344 if (reg != GIC_PIDR2_ARCH_GICv3 &&
345 reg != GIC_PIDR2_ARCH_GICv4) { /* We're in trouble... */
346 pr_warn("No redistributor present @%p\n", ptr);
351 typer = readq_relaxed(ptr + GICR_TYPER);
352 if ((typer >> 32) == aff) {
353 gic_data_rdist_rd_base() = ptr;
354 pr_info("CPU%d: found redistributor %llx @%p\n",
356 (unsigned long long)mpidr, ptr);
360 if (gic_data.redist_stride) {
361 ptr += gic_data.redist_stride;
363 ptr += SZ_64K * 2; /* Skip RD_base + SGI_base */
364 if (typer & GICR_TYPER_VLPIS)
365 ptr += SZ_64K * 2; /* Skip VLPI_base + reserved page */
367 } while (!(typer & GICR_TYPER_LAST));
370 /* We couldn't even deal with ourselves... */
371 WARN(true, "CPU%d: mpidr %llx has no re-distributor!\n",
372 smp_processor_id(), (unsigned long long)mpidr);
376 static void gic_cpu_init(void)
380 /* Register ourselves with the rest of the world */
381 if (gic_populate_rdist())
386 rbase = gic_data_rdist_sgi_base();
388 gic_cpu_config(rbase, gic_redist_wait_for_rwp);
390 /* Enable system registers */
393 /* Set priority mask register */
394 gic_write_pmr(DEFAULT_PMR_VALUE);
396 /* EOI deactivates interrupt too (mode 0) */
397 gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop_dir);
399 /* ... and let's hit the road... */
404 static int gic_secondary_init(struct notifier_block *nfb,
405 unsigned long action, void *hcpu)
407 if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
413 * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
414 * priority because the GIC needs to be up before the ARM generic timers.
416 static struct notifier_block gic_cpu_notifier = {
417 .notifier_call = gic_secondary_init,
421 static u16 gic_compute_target_list(int *base_cpu, const struct cpumask *mask,
425 u64 mpidr = cpu_logical_map(cpu);
428 while (cpu < nr_cpu_ids) {
430 * If we ever get a cluster of more than 16 CPUs, just
431 * scream and skip that CPU.
433 if (WARN_ON((mpidr & 0xff) >= 16))
436 tlist |= 1 << (mpidr & 0xf);
438 cpu = cpumask_next(cpu, mask);
439 if (cpu == nr_cpu_ids)
442 mpidr = cpu_logical_map(cpu);
444 if (cluster_id != (mpidr & ~0xffUL)) {
454 static void gic_send_sgi(u64 cluster_id, u16 tlist, unsigned int irq)
458 val = (MPIDR_AFFINITY_LEVEL(cluster_id, 3) << 48 |
459 MPIDR_AFFINITY_LEVEL(cluster_id, 2) << 32 |
461 MPIDR_AFFINITY_LEVEL(cluster_id, 1) << 16 |
464 pr_debug("CPU%d: ICC_SGI1R_EL1 %llx\n", smp_processor_id(), val);
465 gic_write_sgi1r(val);
468 static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
472 if (WARN_ON(irq >= 16))
476 * Ensure that stores to Normal memory are visible to the
477 * other CPUs before issuing the IPI.
481 for_each_cpu_mask(cpu, *mask) {
482 u64 cluster_id = cpu_logical_map(cpu) & ~0xffUL;
485 tlist = gic_compute_target_list(&cpu, mask, cluster_id);
486 gic_send_sgi(cluster_id, tlist, irq);
489 /* Force the above writes to ICC_SGI1R_EL1 to be executed */
493 static void gic_smp_init(void)
495 set_smp_cross_call(gic_raise_softirq);
496 register_cpu_notifier(&gic_cpu_notifier);
499 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
502 unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
507 if (gic_irq_in_rdist(d))
510 /* If interrupt was enabled, disable it first */
511 enabled = gic_peek_irq(d, GICD_ISENABLER);
515 reg = gic_dist_base(d) + GICD_IROUTER + (gic_irq(d) * 8);
516 val = gic_mpidr_to_affinity(cpu_logical_map(cpu));
518 writeq_relaxed(val, reg);
521 * If the interrupt was enabled, enabled it again. Otherwise,
522 * just wait for the distributor to have digested our changes.
527 gic_dist_wait_for_rwp();
529 return IRQ_SET_MASK_OK;
532 #define gic_set_affinity NULL
533 #define gic_smp_init() do { } while(0)
536 static struct irq_chip gic_chip = {
538 .irq_mask = gic_mask_irq,
539 .irq_unmask = gic_unmask_irq,
540 .irq_eoi = gic_eoi_irq,
541 .irq_set_type = gic_set_type,
542 .irq_set_affinity = gic_set_affinity,
545 static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
548 /* SGIs are private to the core kernel */
553 irq_set_percpu_devid(irq);
554 irq_set_chip_and_handler(irq, &gic_chip,
555 handle_percpu_devid_irq);
556 set_irq_flags(irq, IRQF_VALID | IRQF_NOAUTOEN);
559 if (hw >= 32 && hw < gic_data.irq_nr) {
560 irq_set_chip_and_handler(irq, &gic_chip,
562 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
564 irq_set_chip_data(irq, d->host_data);
568 static int gic_irq_domain_xlate(struct irq_domain *d,
569 struct device_node *controller,
570 const u32 *intspec, unsigned int intsize,
571 unsigned long *out_hwirq, unsigned int *out_type)
573 if (d->of_node != controller)
580 *out_hwirq = intspec[1] + 32;
583 *out_hwirq = intspec[1] + 16;
589 *out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
593 static const struct irq_domain_ops gic_irq_domain_ops = {
594 .map = gic_irq_domain_map,
595 .xlate = gic_irq_domain_xlate,
598 static int __init gic_of_init(struct device_node *node, struct device_node *parent)
600 void __iomem *dist_base;
601 void __iomem **redist_base;
609 dist_base = of_iomap(node, 0);
611 pr_err("%s: unable to map gic dist registers\n",
616 reg = readl_relaxed(dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;
617 if (reg != GIC_PIDR2_ARCH_GICv3 && reg != GIC_PIDR2_ARCH_GICv4) {
618 pr_err("%s: no distributor detected, giving up\n",
624 if (of_property_read_u32(node, "#redistributor-regions", &redist_regions))
627 redist_base = kzalloc(sizeof(*redist_base) * redist_regions, GFP_KERNEL);
633 for (i = 0; i < redist_regions; i++) {
634 redist_base[i] = of_iomap(node, 1 + i);
635 if (!redist_base[i]) {
636 pr_err("%s: couldn't map region %d\n",
639 goto out_unmap_rdist;
643 if (of_property_read_u64(node, "redistributor-stride", &redist_stride))
646 gic_data.dist_base = dist_base;
647 gic_data.redist_base = redist_base;
648 gic_data.redist_regions = redist_regions;
649 gic_data.redist_stride = redist_stride;
652 * Find out how many interrupts are supported.
653 * The GIC only supports up to 1020 interrupt sources (SGI+PPI+SPI)
655 gic_irqs = readl_relaxed(gic_data.dist_base + GICD_TYPER) & 0x1f;
656 gic_irqs = (gic_irqs + 1) * 32;
659 gic_data.irq_nr = gic_irqs;
661 gic_data.domain = irq_domain_add_tree(node, &gic_irq_domain_ops,
663 gic_data.rdist = alloc_percpu(typeof(*gic_data.rdist));
665 if (WARN_ON(!gic_data.domain) || WARN_ON(!gic_data.rdist)) {
670 set_handle_irq(gic_handle_irq);
680 irq_domain_remove(gic_data.domain);
681 free_percpu(gic_data.rdist);
683 for (i = 0; i < redist_regions; i++)
685 iounmap(redist_base[i]);
692 IRQCHIP_DECLARE(gic_v3, "arm,gic-v3", gic_of_init);