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/cpu_pm.h>
20 #include <linux/delay.h>
21 #include <linux/interrupt.h>
23 #include <linux/of_address.h>
24 #include <linux/of_irq.h>
25 #include <linux/percpu.h>
26 #include <linux/slab.h>
28 #include <linux/irqchip/arm-gic-v3.h>
30 #include <asm/cputype.h>
31 #include <asm/exception.h>
32 #include <asm/smp_plat.h>
34 #include "irq-gic-common.h"
37 struct redist_region
{
38 void __iomem
*redist_base
;
39 phys_addr_t phys_base
;
42 struct gic_chip_data
{
43 void __iomem
*dist_base
;
44 struct redist_region
*redist_regions
;
46 struct irq_domain
*domain
;
48 u32 nr_redist_regions
;
52 static struct gic_chip_data gic_data __read_mostly
;
54 #define gic_data_rdist() (this_cpu_ptr(gic_data.rdists.rdist))
55 #define gic_data_rdist_rd_base() (gic_data_rdist()->rd_base)
56 #define gic_data_rdist_sgi_base() (gic_data_rdist_rd_base() + SZ_64K)
58 /* Our default, arbitrary priority value. Linux only uses one anyway. */
59 #define DEFAULT_PMR_VALUE 0xf0
61 static inline unsigned int gic_irq(struct irq_data
*d
)
66 static inline int gic_irq_in_rdist(struct irq_data
*d
)
68 return gic_irq(d
) < 32;
71 static inline void __iomem
*gic_dist_base(struct irq_data
*d
)
73 if (gic_irq_in_rdist(d
)) /* SGI+PPI -> SGI_base for this CPU */
74 return gic_data_rdist_sgi_base();
76 if (d
->hwirq
<= 1023) /* SPI -> dist_base */
77 return gic_data
.dist_base
;
82 static void gic_do_wait_for_rwp(void __iomem
*base
)
84 u32 count
= 1000000; /* 1s! */
86 while (readl_relaxed(base
+ GICD_CTLR
) & GICD_CTLR_RWP
) {
89 pr_err_ratelimited("RWP timeout, gone fishing\n");
97 /* Wait for completion of a distributor change */
98 static void gic_dist_wait_for_rwp(void)
100 gic_do_wait_for_rwp(gic_data
.dist_base
);
103 /* Wait for completion of a redistributor change */
104 static void gic_redist_wait_for_rwp(void)
106 gic_do_wait_for_rwp(gic_data_rdist_rd_base());
109 /* Low level accessors */
110 static u64 __maybe_unused
gic_read_iar(void)
114 asm volatile("mrs_s %0, " __stringify(ICC_IAR1_EL1
) : "=r" (irqstat
));
118 static void __maybe_unused
gic_write_pmr(u64 val
)
120 asm volatile("msr_s " __stringify(ICC_PMR_EL1
) ", %0" : : "r" (val
));
123 static void __maybe_unused
gic_write_ctlr(u64 val
)
125 asm volatile("msr_s " __stringify(ICC_CTLR_EL1
) ", %0" : : "r" (val
));
129 static void __maybe_unused
gic_write_grpen1(u64 val
)
131 asm volatile("msr_s " __stringify(ICC_GRPEN1_EL1
) ", %0" : : "r" (val
));
135 static void __maybe_unused
gic_write_sgi1r(u64 val
)
137 asm volatile("msr_s " __stringify(ICC_SGI1R_EL1
) ", %0" : : "r" (val
));
140 static void gic_enable_sre(void)
144 asm volatile("mrs_s %0, " __stringify(ICC_SRE_EL1
) : "=r" (val
));
145 val
|= ICC_SRE_EL1_SRE
;
146 asm volatile("msr_s " __stringify(ICC_SRE_EL1
) ", %0" : : "r" (val
));
150 * Need to check that the SRE bit has actually been set. If
151 * not, it means that SRE is disabled at EL2. We're going to
152 * die painfully, and there is nothing we can do about it.
154 * Kindly inform the luser.
156 asm volatile("mrs_s %0, " __stringify(ICC_SRE_EL1
) : "=r" (val
));
157 if (!(val
& ICC_SRE_EL1_SRE
))
158 pr_err("GIC: unable to set SRE (disabled at EL2), panic ahead\n");
161 static void gic_enable_redist(bool enable
)
164 u32 count
= 1000000; /* 1s! */
167 rbase
= gic_data_rdist_rd_base();
169 val
= readl_relaxed(rbase
+ GICR_WAKER
);
171 /* Wake up this CPU redistributor */
172 val
&= ~GICR_WAKER_ProcessorSleep
;
174 val
|= GICR_WAKER_ProcessorSleep
;
175 writel_relaxed(val
, rbase
+ GICR_WAKER
);
177 if (!enable
) { /* Check that GICR_WAKER is writeable */
178 val
= readl_relaxed(rbase
+ GICR_WAKER
);
179 if (!(val
& GICR_WAKER_ProcessorSleep
))
180 return; /* No PM support in this redistributor */
184 val
= readl_relaxed(rbase
+ GICR_WAKER
);
185 if (enable
^ (val
& GICR_WAKER_ChildrenAsleep
))
191 pr_err_ratelimited("redistributor failed to %s...\n",
192 enable
? "wakeup" : "sleep");
196 * Routines to disable, enable, EOI and route interrupts
198 static void gic_poke_irq(struct irq_data
*d
, u32 offset
)
200 u32 mask
= 1 << (gic_irq(d
) % 32);
201 void (*rwp_wait
)(void);
204 if (gic_irq_in_rdist(d
)) {
205 base
= gic_data_rdist_sgi_base();
206 rwp_wait
= gic_redist_wait_for_rwp
;
208 base
= gic_data
.dist_base
;
209 rwp_wait
= gic_dist_wait_for_rwp
;
212 writel_relaxed(mask
, base
+ offset
+ (gic_irq(d
) / 32) * 4);
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) || irqnr
>= 8192) {
278 err
= handle_domain_irq(gic_data
.domain
, irqnr
, regs
);
280 WARN_ONCE(true, "Unexpected interrupt received!\n");
281 gic_write_eoir(irqnr
);
286 gic_write_eoir(irqnr
);
288 handle_IPI(irqnr
, regs
);
290 WARN_ONCE(true, "Unexpected SGI received!\n");
294 } while (irqnr
!= ICC_IAR1_EL1_SPURIOUS
);
297 static void __init
gic_dist_init(void)
301 void __iomem
*base
= gic_data
.dist_base
;
303 /* Disable the distributor */
304 writel_relaxed(0, base
+ GICD_CTLR
);
305 gic_dist_wait_for_rwp();
307 gic_dist_config(base
, gic_data
.irq_nr
, gic_dist_wait_for_rwp
);
309 /* Enable distributor with ARE, Group1 */
310 writel_relaxed(GICD_CTLR_ARE_NS
| GICD_CTLR_ENABLE_G1A
| GICD_CTLR_ENABLE_G1
,
314 * Set all global interrupts to the boot CPU only. ARE must be
317 affinity
= gic_mpidr_to_affinity(cpu_logical_map(smp_processor_id()));
318 for (i
= 32; i
< gic_data
.irq_nr
; i
++)
319 writeq_relaxed(affinity
, base
+ GICD_IROUTER
+ i
* 8);
322 static int gic_populate_rdist(void)
324 u64 mpidr
= cpu_logical_map(smp_processor_id());
330 * Convert affinity to a 32bit value that can be matched to
331 * GICR_TYPER bits [63:32].
333 aff
= (MPIDR_AFFINITY_LEVEL(mpidr
, 3) << 24 |
334 MPIDR_AFFINITY_LEVEL(mpidr
, 2) << 16 |
335 MPIDR_AFFINITY_LEVEL(mpidr
, 1) << 8 |
336 MPIDR_AFFINITY_LEVEL(mpidr
, 0));
338 for (i
= 0; i
< gic_data
.nr_redist_regions
; i
++) {
339 void __iomem
*ptr
= gic_data
.redist_regions
[i
].redist_base
;
342 reg
= readl_relaxed(ptr
+ GICR_PIDR2
) & GIC_PIDR2_ARCH_MASK
;
343 if (reg
!= GIC_PIDR2_ARCH_GICv3
&&
344 reg
!= GIC_PIDR2_ARCH_GICv4
) { /* We're in trouble... */
345 pr_warn("No redistributor present @%p\n", ptr
);
350 typer
= readq_relaxed(ptr
+ GICR_TYPER
);
351 if ((typer
>> 32) == aff
) {
352 u64 offset
= ptr
- gic_data
.redist_regions
[i
].redist_base
;
353 gic_data_rdist_rd_base() = ptr
;
354 gic_data_rdist()->phys_base
= gic_data
.redist_regions
[i
].phys_base
+ offset
;
355 pr_info("CPU%d: found redistributor %llx region %d:%pa\n",
357 (unsigned long long)mpidr
,
358 i
, &gic_data_rdist()->phys_base
);
362 if (gic_data
.redist_stride
) {
363 ptr
+= gic_data
.redist_stride
;
365 ptr
+= SZ_64K
* 2; /* Skip RD_base + SGI_base */
366 if (typer
& GICR_TYPER_VLPIS
)
367 ptr
+= SZ_64K
* 2; /* Skip VLPI_base + reserved page */
369 } while (!(typer
& GICR_TYPER_LAST
));
372 /* We couldn't even deal with ourselves... */
373 WARN(true, "CPU%d: mpidr %llx has no re-distributor!\n",
374 smp_processor_id(), (unsigned long long)mpidr
);
378 static void gic_cpu_sys_reg_init(void)
380 /* Enable system registers */
383 /* Set priority mask register */
384 gic_write_pmr(DEFAULT_PMR_VALUE
);
386 /* EOI deactivates interrupt too (mode 0) */
387 gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop_dir
);
389 /* ... and let's hit the road... */
393 static int gic_dist_supports_lpis(void)
395 return !!(readl_relaxed(gic_data
.dist_base
+ GICD_TYPER
) & GICD_TYPER_LPIS
);
398 static void gic_cpu_init(void)
402 /* Register ourselves with the rest of the world */
403 if (gic_populate_rdist())
406 gic_enable_redist(true);
408 rbase
= gic_data_rdist_sgi_base();
410 gic_cpu_config(rbase
, gic_redist_wait_for_rwp
);
412 /* Give LPIs a spin */
413 if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS
) && gic_dist_supports_lpis())
416 /* initialise system registers */
417 gic_cpu_sys_reg_init();
421 static int gic_peek_irq(struct irq_data
*d
, u32 offset
)
423 u32 mask
= 1 << (gic_irq(d
) % 32);
426 if (gic_irq_in_rdist(d
))
427 base
= gic_data_rdist_sgi_base();
429 base
= gic_data
.dist_base
;
431 return !!(readl_relaxed(base
+ offset
+ (gic_irq(d
) / 32) * 4) & mask
);
434 static int gic_secondary_init(struct notifier_block
*nfb
,
435 unsigned long action
, void *hcpu
)
437 if (action
== CPU_STARTING
|| action
== CPU_STARTING_FROZEN
)
443 * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
444 * priority because the GIC needs to be up before the ARM generic timers.
446 static struct notifier_block gic_cpu_notifier
= {
447 .notifier_call
= gic_secondary_init
,
451 static u16
gic_compute_target_list(int *base_cpu
, const struct cpumask
*mask
,
455 u64 mpidr
= cpu_logical_map(cpu
);
458 while (cpu
< nr_cpu_ids
) {
460 * If we ever get a cluster of more than 16 CPUs, just
461 * scream and skip that CPU.
463 if (WARN_ON((mpidr
& 0xff) >= 16))
466 tlist
|= 1 << (mpidr
& 0xf);
468 cpu
= cpumask_next(cpu
, mask
);
469 if (cpu
== nr_cpu_ids
)
472 mpidr
= cpu_logical_map(cpu
);
474 if (cluster_id
!= (mpidr
& ~0xffUL
)) {
484 static void gic_send_sgi(u64 cluster_id
, u16 tlist
, unsigned int irq
)
488 val
= (MPIDR_AFFINITY_LEVEL(cluster_id
, 3) << 48 |
489 MPIDR_AFFINITY_LEVEL(cluster_id
, 2) << 32 |
491 MPIDR_AFFINITY_LEVEL(cluster_id
, 1) << 16 |
494 pr_debug("CPU%d: ICC_SGI1R_EL1 %llx\n", smp_processor_id(), val
);
495 gic_write_sgi1r(val
);
498 static void gic_raise_softirq(const struct cpumask
*mask
, unsigned int irq
)
502 if (WARN_ON(irq
>= 16))
506 * Ensure that stores to Normal memory are visible to the
507 * other CPUs before issuing the IPI.
511 for_each_cpu_mask(cpu
, *mask
) {
512 u64 cluster_id
= cpu_logical_map(cpu
) & ~0xffUL
;
515 tlist
= gic_compute_target_list(&cpu
, mask
, cluster_id
);
516 gic_send_sgi(cluster_id
, tlist
, irq
);
519 /* Force the above writes to ICC_SGI1R_EL1 to be executed */
523 static void gic_smp_init(void)
525 set_smp_cross_call(gic_raise_softirq
);
526 register_cpu_notifier(&gic_cpu_notifier
);
529 static int gic_set_affinity(struct irq_data
*d
, const struct cpumask
*mask_val
,
532 unsigned int cpu
= cpumask_any_and(mask_val
, cpu_online_mask
);
537 if (gic_irq_in_rdist(d
))
540 /* If interrupt was enabled, disable it first */
541 enabled
= gic_peek_irq(d
, GICD_ISENABLER
);
545 reg
= gic_dist_base(d
) + GICD_IROUTER
+ (gic_irq(d
) * 8);
546 val
= gic_mpidr_to_affinity(cpu_logical_map(cpu
));
548 writeq_relaxed(val
, reg
);
551 * If the interrupt was enabled, enabled it again. Otherwise,
552 * just wait for the distributor to have digested our changes.
557 gic_dist_wait_for_rwp();
559 return IRQ_SET_MASK_OK
;
562 #define gic_set_affinity NULL
563 #define gic_smp_init() do { } while(0)
567 static int gic_cpu_pm_notifier(struct notifier_block
*self
,
568 unsigned long cmd
, void *v
)
570 if (cmd
== CPU_PM_EXIT
) {
571 gic_enable_redist(true);
572 gic_cpu_sys_reg_init();
573 } else if (cmd
== CPU_PM_ENTER
) {
575 gic_enable_redist(false);
580 static struct notifier_block gic_cpu_pm_notifier_block
= {
581 .notifier_call
= gic_cpu_pm_notifier
,
584 static void gic_cpu_pm_init(void)
586 cpu_pm_register_notifier(&gic_cpu_pm_notifier_block
);
590 static inline void gic_cpu_pm_init(void) { }
591 #endif /* CONFIG_CPU_PM */
593 static struct irq_chip gic_chip
= {
595 .irq_mask
= gic_mask_irq
,
596 .irq_unmask
= gic_unmask_irq
,
597 .irq_eoi
= gic_eoi_irq
,
598 .irq_set_type
= gic_set_type
,
599 .irq_set_affinity
= gic_set_affinity
,
602 #define GIC_ID_NR (1U << gic_data.rdists.id_bits)
604 static int gic_irq_domain_map(struct irq_domain
*d
, unsigned int irq
,
607 /* SGIs are private to the core kernel */
611 if (hw
>= gic_data
.irq_nr
&& hw
< 8192)
619 irq_set_percpu_devid(irq
);
620 irq_domain_set_info(d
, irq
, hw
, &gic_chip
, d
->host_data
,
621 handle_percpu_devid_irq
, NULL
, NULL
);
622 set_irq_flags(irq
, IRQF_VALID
| IRQF_NOAUTOEN
);
625 if (hw
>= 32 && hw
< gic_data
.irq_nr
) {
626 irq_domain_set_info(d
, irq
, hw
, &gic_chip
, d
->host_data
,
627 handle_fasteoi_irq
, NULL
, NULL
);
628 set_irq_flags(irq
, IRQF_VALID
| IRQF_PROBE
);
631 if (hw
>= 8192 && hw
< GIC_ID_NR
) {
632 if (!gic_dist_supports_lpis())
634 irq_domain_set_info(d
, irq
, hw
, &gic_chip
, d
->host_data
,
635 handle_fasteoi_irq
, NULL
, NULL
);
636 set_irq_flags(irq
, IRQF_VALID
);
642 static int gic_irq_domain_xlate(struct irq_domain
*d
,
643 struct device_node
*controller
,
644 const u32
*intspec
, unsigned int intsize
,
645 unsigned long *out_hwirq
, unsigned int *out_type
)
647 if (d
->of_node
!= controller
)
654 *out_hwirq
= intspec
[1] + 32;
657 *out_hwirq
= intspec
[1] + 16;
659 case GIC_IRQ_TYPE_LPI
: /* LPI */
660 *out_hwirq
= intspec
[1];
666 *out_type
= intspec
[2] & IRQ_TYPE_SENSE_MASK
;
670 static int gic_irq_domain_alloc(struct irq_domain
*domain
, unsigned int virq
,
671 unsigned int nr_irqs
, void *arg
)
674 irq_hw_number_t hwirq
;
675 unsigned int type
= IRQ_TYPE_NONE
;
676 struct of_phandle_args
*irq_data
= arg
;
678 ret
= gic_irq_domain_xlate(domain
, irq_data
->np
, irq_data
->args
,
679 irq_data
->args_count
, &hwirq
, &type
);
683 for (i
= 0; i
< nr_irqs
; i
++)
684 gic_irq_domain_map(domain
, virq
+ i
, hwirq
+ i
);
689 static void gic_irq_domain_free(struct irq_domain
*domain
, unsigned int virq
,
690 unsigned int nr_irqs
)
694 for (i
= 0; i
< nr_irqs
; i
++) {
695 struct irq_data
*d
= irq_domain_get_irq_data(domain
, virq
+ i
);
696 irq_set_handler(virq
+ i
, NULL
);
697 irq_domain_reset_irq_data(d
);
701 static const struct irq_domain_ops gic_irq_domain_ops
= {
702 .xlate
= gic_irq_domain_xlate
,
703 .alloc
= gic_irq_domain_alloc
,
704 .free
= gic_irq_domain_free
,
707 static int __init
gic_of_init(struct device_node
*node
, struct device_node
*parent
)
709 void __iomem
*dist_base
;
710 struct redist_region
*rdist_regs
;
712 u32 nr_redist_regions
;
719 dist_base
= of_iomap(node
, 0);
721 pr_err("%s: unable to map gic dist registers\n",
726 reg
= readl_relaxed(dist_base
+ GICD_PIDR2
) & GIC_PIDR2_ARCH_MASK
;
727 if (reg
!= GIC_PIDR2_ARCH_GICv3
&& reg
!= GIC_PIDR2_ARCH_GICv4
) {
728 pr_err("%s: no distributor detected, giving up\n",
734 if (of_property_read_u32(node
, "#redistributor-regions", &nr_redist_regions
))
735 nr_redist_regions
= 1;
737 rdist_regs
= kzalloc(sizeof(*rdist_regs
) * nr_redist_regions
, GFP_KERNEL
);
743 for (i
= 0; i
< nr_redist_regions
; i
++) {
747 ret
= of_address_to_resource(node
, 1 + i
, &res
);
748 rdist_regs
[i
].redist_base
= of_iomap(node
, 1 + i
);
749 if (ret
|| !rdist_regs
[i
].redist_base
) {
750 pr_err("%s: couldn't map region %d\n",
753 goto out_unmap_rdist
;
755 rdist_regs
[i
].phys_base
= res
.start
;
758 if (of_property_read_u64(node
, "redistributor-stride", &redist_stride
))
761 gic_data
.dist_base
= dist_base
;
762 gic_data
.redist_regions
= rdist_regs
;
763 gic_data
.nr_redist_regions
= nr_redist_regions
;
764 gic_data
.redist_stride
= redist_stride
;
767 * Find out how many interrupts are supported.
768 * The GIC only supports up to 1020 interrupt sources (SGI+PPI+SPI)
770 typer
= readl_relaxed(gic_data
.dist_base
+ GICD_TYPER
);
771 gic_data
.rdists
.id_bits
= GICD_TYPER_ID_BITS(typer
);
772 gic_irqs
= GICD_TYPER_IRQS(typer
);
775 gic_data
.irq_nr
= gic_irqs
;
777 gic_data
.domain
= irq_domain_add_tree(node
, &gic_irq_domain_ops
,
779 gic_data
.rdists
.rdist
= alloc_percpu(typeof(*gic_data
.rdists
.rdist
));
781 if (WARN_ON(!gic_data
.domain
) || WARN_ON(!gic_data
.rdists
.rdist
)) {
786 set_handle_irq(gic_handle_irq
);
788 if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS
) && gic_dist_supports_lpis())
789 its_init(node
, &gic_data
.rdists
, gic_data
.domain
);
800 irq_domain_remove(gic_data
.domain
);
801 free_percpu(gic_data
.rdists
.rdist
);
803 for (i
= 0; i
< nr_redist_regions
; i
++)
804 if (rdist_regs
[i
].redist_base
)
805 iounmap(rdist_regs
[i
].redist_base
);
812 IRQCHIP_DECLARE(gic_v3
, "arm,gic-v3", gic_of_init
);