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path: root/drivers/irqchip/irq-gic-v3.c
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Diffstat (limited to 'drivers/irqchip/irq-gic-v3.c')
-rw-r--r--drivers/irqchip/irq-gic-v3.c692
1 files changed, 692 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
new file mode 100644
index 000000000000..57eaa5a0b1e3
--- /dev/null
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -0,0 +1,692 @@
+/*
+ * Copyright (C) 2013, 2014 ARM Limited, All Rights Reserved.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/percpu.h>
+#include <linux/slab.h>
+
+#include <linux/irqchip/arm-gic-v3.h>
+
+#include <asm/cputype.h>
+#include <asm/exception.h>
+#include <asm/smp_plat.h>
+
+#include "irq-gic-common.h"
+#include "irqchip.h"
+
+struct gic_chip_data {
+ void __iomem *dist_base;
+ void __iomem **redist_base;
+ void __percpu __iomem **rdist;
+ struct irq_domain *domain;
+ u64 redist_stride;
+ u32 redist_regions;
+ unsigned int irq_nr;
+};
+
+static struct gic_chip_data gic_data __read_mostly;
+
+#define gic_data_rdist() (this_cpu_ptr(gic_data.rdist))
+#define gic_data_rdist_rd_base() (*gic_data_rdist())
+#define gic_data_rdist_sgi_base() (gic_data_rdist_rd_base() + SZ_64K)
+
+/* Our default, arbitrary priority value. Linux only uses one anyway. */
+#define DEFAULT_PMR_VALUE 0xf0
+
+static inline unsigned int gic_irq(struct irq_data *d)
+{
+ return d->hwirq;
+}
+
+static inline int gic_irq_in_rdist(struct irq_data *d)
+{
+ return gic_irq(d) < 32;
+}
+
+static inline void __iomem *gic_dist_base(struct irq_data *d)
+{
+ if (gic_irq_in_rdist(d)) /* SGI+PPI -> SGI_base for this CPU */
+ return gic_data_rdist_sgi_base();
+
+ if (d->hwirq <= 1023) /* SPI -> dist_base */
+ return gic_data.dist_base;
+
+ if (d->hwirq >= 8192)
+ BUG(); /* LPI Detected!!! */
+
+ return NULL;
+}
+
+static void gic_do_wait_for_rwp(void __iomem *base)
+{
+ u32 count = 1000000; /* 1s! */
+
+ while (readl_relaxed(base + GICD_CTLR) & GICD_CTLR_RWP) {
+ count--;
+ if (!count) {
+ pr_err_ratelimited("RWP timeout, gone fishing\n");
+ return;
+ }
+ cpu_relax();
+ udelay(1);
+ };
+}
+
+/* Wait for completion of a distributor change */
+static void gic_dist_wait_for_rwp(void)
+{
+ gic_do_wait_for_rwp(gic_data.dist_base);
+}
+
+/* Wait for completion of a redistributor change */
+static void gic_redist_wait_for_rwp(void)
+{
+ gic_do_wait_for_rwp(gic_data_rdist_rd_base());
+}
+
+/* Low level accessors */
+static u64 gic_read_iar(void)
+{
+ u64 irqstat;
+
+ asm volatile("mrs_s %0, " __stringify(ICC_IAR1_EL1) : "=r" (irqstat));
+ return irqstat;
+}
+
+static void gic_write_pmr(u64 val)
+{
+ asm volatile("msr_s " __stringify(ICC_PMR_EL1) ", %0" : : "r" (val));
+}
+
+static void gic_write_ctlr(u64 val)
+{
+ asm volatile("msr_s " __stringify(ICC_CTLR_EL1) ", %0" : : "r" (val));
+ isb();
+}
+
+static void gic_write_grpen1(u64 val)
+{
+ asm volatile("msr_s " __stringify(ICC_GRPEN1_EL1) ", %0" : : "r" (val));
+ isb();
+}
+
+static void gic_write_sgi1r(u64 val)
+{
+ asm volatile("msr_s " __stringify(ICC_SGI1R_EL1) ", %0" : : "r" (val));
+}
+
+static void gic_enable_sre(void)
+{
+ u64 val;
+
+ asm volatile("mrs_s %0, " __stringify(ICC_SRE_EL1) : "=r" (val));
+ val |= ICC_SRE_EL1_SRE;
+ asm volatile("msr_s " __stringify(ICC_SRE_EL1) ", %0" : : "r" (val));
+ isb();
+
+ /*
+ * Need to check that the SRE bit has actually been set. If
+ * not, it means that SRE is disabled at EL2. We're going to
+ * die painfully, and there is nothing we can do about it.
+ *
+ * Kindly inform the luser.
+ */
+ asm volatile("mrs_s %0, " __stringify(ICC_SRE_EL1) : "=r" (val));
+ if (!(val & ICC_SRE_EL1_SRE))
+ pr_err("GIC: unable to set SRE (disabled at EL2), panic ahead\n");
+}
+
+static void gic_enable_redist(void)
+{
+ void __iomem *rbase;
+ u32 count = 1000000; /* 1s! */
+ u32 val;
+
+ rbase = gic_data_rdist_rd_base();
+
+ /* Wake up this CPU redistributor */
+ val = readl_relaxed(rbase + GICR_WAKER);
+ val &= ~GICR_WAKER_ProcessorSleep;
+ writel_relaxed(val, rbase + GICR_WAKER);
+
+ while (readl_relaxed(rbase + GICR_WAKER) & GICR_WAKER_ChildrenAsleep) {
+ count--;
+ if (!count) {
+ pr_err_ratelimited("redist didn't wake up...\n");
+ return;
+ }
+ cpu_relax();
+ udelay(1);
+ };
+}
+
+/*
+ * Routines to disable, enable, EOI and route interrupts
+ */
+static void gic_poke_irq(struct irq_data *d, u32 offset)
+{
+ u32 mask = 1 << (gic_irq(d) % 32);
+ void (*rwp_wait)(void);
+ void __iomem *base;
+
+ if (gic_irq_in_rdist(d)) {
+ base = gic_data_rdist_sgi_base();
+ rwp_wait = gic_redist_wait_for_rwp;
+ } else {
+ base = gic_data.dist_base;
+ rwp_wait = gic_dist_wait_for_rwp;
+ }
+
+ writel_relaxed(mask, base + offset + (gic_irq(d) / 32) * 4);
+ rwp_wait();
+}
+
+static int gic_peek_irq(struct irq_data *d, u32 offset)
+{
+ u32 mask = 1 << (gic_irq(d) % 32);
+ void __iomem *base;
+
+ if (gic_irq_in_rdist(d))
+ base = gic_data_rdist_sgi_base();
+ else
+ base = gic_data.dist_base;
+
+ return !!(readl_relaxed(base + offset + (gic_irq(d) / 32) * 4) & mask);
+}
+
+static void gic_mask_irq(struct irq_data *d)
+{
+ gic_poke_irq(d, GICD_ICENABLER);
+}
+
+static void gic_unmask_irq(struct irq_data *d)
+{
+ gic_poke_irq(d, GICD_ISENABLER);
+}
+
+static void gic_eoi_irq(struct irq_data *d)
+{
+ gic_write_eoir(gic_irq(d));
+}
+
+static int gic_set_type(struct irq_data *d, unsigned int type)
+{
+ unsigned int irq = gic_irq(d);
+ void (*rwp_wait)(void);
+ void __iomem *base;
+
+ /* Interrupt configuration for SGIs can't be changed */
+ if (irq < 16)
+ return -EINVAL;
+
+ if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
+ return -EINVAL;
+
+ if (gic_irq_in_rdist(d)) {
+ base = gic_data_rdist_sgi_base();
+ rwp_wait = gic_redist_wait_for_rwp;
+ } else {
+ base = gic_data.dist_base;
+ rwp_wait = gic_dist_wait_for_rwp;
+ }
+
+ gic_configure_irq(irq, type, base, rwp_wait);
+
+ return 0;
+}
+
+static u64 gic_mpidr_to_affinity(u64 mpidr)
+{
+ u64 aff;
+
+ aff = (MPIDR_AFFINITY_LEVEL(mpidr, 3) << 32 |
+ MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
+ MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8 |
+ MPIDR_AFFINITY_LEVEL(mpidr, 0));
+
+ return aff;
+}
+
+static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
+{
+ u64 irqnr;
+
+ do {
+ irqnr = gic_read_iar();
+
+ if (likely(irqnr > 15 && irqnr < 1020)) {
+ u64 irq = irq_find_mapping(gic_data.domain, irqnr);
+ if (likely(irq)) {
+ handle_IRQ(irq, regs);
+ continue;
+ }
+
+ WARN_ONCE(true, "Unexpected SPI received!\n");
+ gic_write_eoir(irqnr);
+ }
+ if (irqnr < 16) {
+ gic_write_eoir(irqnr);
+#ifdef CONFIG_SMP
+ handle_IPI(irqnr, regs);
+#else
+ WARN_ONCE(true, "Unexpected SGI received!\n");
+#endif
+ continue;
+ }
+ } while (irqnr != ICC_IAR1_EL1_SPURIOUS);
+}
+
+static void __init gic_dist_init(void)
+{
+ unsigned int i;
+ u64 affinity;
+ void __iomem *base = gic_data.dist_base;
+
+ /* Disable the distributor */
+ writel_relaxed(0, base + GICD_CTLR);
+ gic_dist_wait_for_rwp();
+
+ gic_dist_config(base, gic_data.irq_nr, gic_dist_wait_for_rwp);
+
+ /* Enable distributor with ARE, Group1 */
+ writel_relaxed(GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G1A | GICD_CTLR_ENABLE_G1,
+ base + GICD_CTLR);
+
+ /*
+ * Set all global interrupts to the boot CPU only. ARE must be
+ * enabled.
+ */
+ affinity = gic_mpidr_to_affinity(cpu_logical_map(smp_processor_id()));
+ for (i = 32; i < gic_data.irq_nr; i++)
+ writeq_relaxed(affinity, base + GICD_IROUTER + i * 8);
+}
+
+static int gic_populate_rdist(void)
+{
+ u64 mpidr = cpu_logical_map(smp_processor_id());
+ u64 typer;
+ u32 aff;
+ int i;
+
+ /*
+ * Convert affinity to a 32bit value that can be matched to
+ * GICR_TYPER bits [63:32].
+ */
+ aff = (MPIDR_AFFINITY_LEVEL(mpidr, 3) << 24 |
+ MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
+ MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8 |
+ MPIDR_AFFINITY_LEVEL(mpidr, 0));
+
+ for (i = 0; i < gic_data.redist_regions; i++) {
+ void __iomem *ptr = gic_data.redist_base[i];
+ u32 reg;
+
+ reg = readl_relaxed(ptr + GICR_PIDR2) & GIC_PIDR2_ARCH_MASK;
+ if (reg != GIC_PIDR2_ARCH_GICv3 &&
+ reg != GIC_PIDR2_ARCH_GICv4) { /* We're in trouble... */
+ pr_warn("No redistributor present @%p\n", ptr);
+ break;
+ }
+
+ do {
+ typer = readq_relaxed(ptr + GICR_TYPER);
+ if ((typer >> 32) == aff) {
+ gic_data_rdist_rd_base() = ptr;
+ pr_info("CPU%d: found redistributor %llx @%p\n",
+ smp_processor_id(),
+ (unsigned long long)mpidr, ptr);
+ return 0;
+ }
+
+ if (gic_data.redist_stride) {
+ ptr += gic_data.redist_stride;
+ } else {
+ ptr += SZ_64K * 2; /* Skip RD_base + SGI_base */
+ if (typer & GICR_TYPER_VLPIS)
+ ptr += SZ_64K * 2; /* Skip VLPI_base + reserved page */
+ }
+ } while (!(typer & GICR_TYPER_LAST));
+ }
+
+ /* We couldn't even deal with ourselves... */
+ WARN(true, "CPU%d: mpidr %llx has no re-distributor!\n",
+ smp_processor_id(), (unsigned long long)mpidr);
+ return -ENODEV;
+}
+
+static void gic_cpu_init(void)
+{
+ void __iomem *rbase;
+
+ /* Register ourselves with the rest of the world */
+ if (gic_populate_rdist())
+ return;
+
+ gic_enable_redist();
+
+ rbase = gic_data_rdist_sgi_base();
+
+ gic_cpu_config(rbase, gic_redist_wait_for_rwp);
+
+ /* Enable system registers */
+ gic_enable_sre();
+
+ /* Set priority mask register */
+ gic_write_pmr(DEFAULT_PMR_VALUE);
+
+ /* EOI deactivates interrupt too (mode 0) */
+ gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop_dir);
+
+ /* ... and let's hit the road... */
+ gic_write_grpen1(1);
+}
+
+#ifdef CONFIG_SMP
+static int gic_secondary_init(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
+ gic_cpu_init();
+ return NOTIFY_OK;
+}
+
+/*
+ * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
+ * priority because the GIC needs to be up before the ARM generic timers.
+ */
+static struct notifier_block gic_cpu_notifier = {
+ .notifier_call = gic_secondary_init,
+ .priority = 100,
+};
+
+static u16 gic_compute_target_list(int *base_cpu, const struct cpumask *mask,
+ u64 cluster_id)
+{
+ int cpu = *base_cpu;
+ u64 mpidr = cpu_logical_map(cpu);
+ u16 tlist = 0;
+
+ while (cpu < nr_cpu_ids) {
+ /*
+ * If we ever get a cluster of more than 16 CPUs, just
+ * scream and skip that CPU.
+ */
+ if (WARN_ON((mpidr & 0xff) >= 16))
+ goto out;
+
+ tlist |= 1 << (mpidr & 0xf);
+
+ cpu = cpumask_next(cpu, mask);
+ if (cpu == nr_cpu_ids)
+ goto out;
+
+ mpidr = cpu_logical_map(cpu);
+
+ if (cluster_id != (mpidr & ~0xffUL)) {
+ cpu--;
+ goto out;
+ }
+ }
+out:
+ *base_cpu = cpu;
+ return tlist;
+}
+
+static void gic_send_sgi(u64 cluster_id, u16 tlist, unsigned int irq)
+{
+ u64 val;
+
+ val = (MPIDR_AFFINITY_LEVEL(cluster_id, 3) << 48 |
+ MPIDR_AFFINITY_LEVEL(cluster_id, 2) << 32 |
+ irq << 24 |
+ MPIDR_AFFINITY_LEVEL(cluster_id, 1) << 16 |
+ tlist);
+
+ pr_debug("CPU%d: ICC_SGI1R_EL1 %llx\n", smp_processor_id(), val);
+ gic_write_sgi1r(val);
+}
+
+static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
+{
+ int cpu;
+
+ if (WARN_ON(irq >= 16))
+ return;
+
+ /*
+ * Ensure that stores to Normal memory are visible to the
+ * other CPUs before issuing the IPI.
+ */
+ smp_wmb();
+
+ for_each_cpu_mask(cpu, *mask) {
+ u64 cluster_id = cpu_logical_map(cpu) & ~0xffUL;
+ u16 tlist;
+
+ tlist = gic_compute_target_list(&cpu, mask, cluster_id);
+ gic_send_sgi(cluster_id, tlist, irq);
+ }
+
+ /* Force the above writes to ICC_SGI1R_EL1 to be executed */
+ isb();
+}
+
+static void gic_smp_init(void)
+{
+ set_smp_cross_call(gic_raise_softirq);
+ register_cpu_notifier(&gic_cpu_notifier);
+}
+
+static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
+ bool force)
+{
+ unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
+ void __iomem *reg;
+ int enabled;
+ u64 val;
+
+ if (gic_irq_in_rdist(d))
+ return -EINVAL;
+
+ /* If interrupt was enabled, disable it first */
+ enabled = gic_peek_irq(d, GICD_ISENABLER);
+ if (enabled)
+ gic_mask_irq(d);
+
+ reg = gic_dist_base(d) + GICD_IROUTER + (gic_irq(d) * 8);
+ val = gic_mpidr_to_affinity(cpu_logical_map(cpu));
+
+ writeq_relaxed(val, reg);
+
+ /*
+ * If the interrupt was enabled, enabled it again. Otherwise,
+ * just wait for the distributor to have digested our changes.
+ */
+ if (enabled)
+ gic_unmask_irq(d);
+ else
+ gic_dist_wait_for_rwp();
+
+ return IRQ_SET_MASK_OK;
+}
+#else
+#define gic_set_affinity NULL
+#define gic_smp_init() do { } while(0)
+#endif
+
+static struct irq_chip gic_chip = {
+ .name = "GICv3",
+ .irq_mask = gic_mask_irq,
+ .irq_unmask = gic_unmask_irq,
+ .irq_eoi = gic_eoi_irq,
+ .irq_set_type = gic_set_type,
+ .irq_set_affinity = gic_set_affinity,
+};
+
+static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hw)
+{
+ /* SGIs are private to the core kernel */
+ if (hw < 16)
+ return -EPERM;
+ /* PPIs */
+ if (hw < 32) {
+ irq_set_percpu_devid(irq);
+ irq_set_chip_and_handler(irq, &gic_chip,
+ handle_percpu_devid_irq);
+ set_irq_flags(irq, IRQF_VALID | IRQF_NOAUTOEN);
+ }
+ /* SPIs */
+ if (hw >= 32 && hw < gic_data.irq_nr) {
+ irq_set_chip_and_handler(irq, &gic_chip,
+ handle_fasteoi_irq);
+ set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+ }
+ irq_set_chip_data(irq, d->host_data);
+ return 0;
+}
+
+static int gic_irq_domain_xlate(struct irq_domain *d,
+ struct device_node *controller,
+ const u32 *intspec, unsigned int intsize,
+ unsigned long *out_hwirq, unsigned int *out_type)
+{
+ if (d->of_node != controller)
+ return -EINVAL;
+ if (intsize < 3)
+ return -EINVAL;
+
+ switch(intspec[0]) {
+ case 0: /* SPI */
+ *out_hwirq = intspec[1] + 32;
+ break;
+ case 1: /* PPI */
+ *out_hwirq = intspec[1] + 16;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ *out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
+ return 0;
+}
+
+static const struct irq_domain_ops gic_irq_domain_ops = {
+ .map = gic_irq_domain_map,
+ .xlate = gic_irq_domain_xlate,
+};
+
+static int __init gic_of_init(struct device_node *node, struct device_node *parent)
+{
+ void __iomem *dist_base;
+ void __iomem **redist_base;
+ u64 redist_stride;
+ u32 redist_regions;
+ u32 reg;
+ int gic_irqs;
+ int err;
+ int i;
+
+ dist_base = of_iomap(node, 0);
+ if (!dist_base) {
+ pr_err("%s: unable to map gic dist registers\n",
+ node->full_name);
+ return -ENXIO;
+ }
+
+ reg = readl_relaxed(dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;
+ if (reg != GIC_PIDR2_ARCH_GICv3 && reg != GIC_PIDR2_ARCH_GICv4) {
+ pr_err("%s: no distributor detected, giving up\n",
+ node->full_name);
+ err = -ENODEV;
+ goto out_unmap_dist;
+ }
+
+ if (of_property_read_u32(node, "#redistributor-regions", &redist_regions))
+ redist_regions = 1;
+
+ redist_base = kzalloc(sizeof(*redist_base) * redist_regions, GFP_KERNEL);
+ if (!redist_base) {
+ err = -ENOMEM;
+ goto out_unmap_dist;
+ }
+
+ for (i = 0; i < redist_regions; i++) {
+ redist_base[i] = of_iomap(node, 1 + i);
+ if (!redist_base[i]) {
+ pr_err("%s: couldn't map region %d\n",
+ node->full_name, i);
+ err = -ENODEV;
+ goto out_unmap_rdist;
+ }
+ }
+
+ if (of_property_read_u64(node, "redistributor-stride", &redist_stride))
+ redist_stride = 0;
+
+ gic_data.dist_base = dist_base;
+ gic_data.redist_base = redist_base;
+ gic_data.redist_regions = redist_regions;
+ gic_data.redist_stride = redist_stride;
+
+ /*
+ * Find out how many interrupts are supported.
+ * The GIC only supports up to 1020 interrupt sources (SGI+PPI+SPI)
+ */
+ gic_irqs = readl_relaxed(gic_data.dist_base + GICD_TYPER) & 0x1f;
+ gic_irqs = (gic_irqs + 1) * 32;
+ if (gic_irqs > 1020)
+ gic_irqs = 1020;
+ gic_data.irq_nr = gic_irqs;
+
+ gic_data.domain = irq_domain_add_tree(node, &gic_irq_domain_ops,
+ &gic_data);
+ gic_data.rdist = alloc_percpu(typeof(*gic_data.rdist));
+
+ if (WARN_ON(!gic_data.domain) || WARN_ON(!gic_data.rdist)) {
+ err = -ENOMEM;
+ goto out_free;
+ }
+
+ set_handle_irq(gic_handle_irq);
+
+ gic_smp_init();
+ gic_dist_init();
+ gic_cpu_init();
+
+ return 0;
+
+out_free:
+ if (gic_data.domain)
+ irq_domain_remove(gic_data.domain);
+ free_percpu(gic_data.rdist);
+out_unmap_rdist:
+ for (i = 0; i < redist_regions; i++)
+ if (redist_base[i])
+ iounmap(redist_base[i]);
+ kfree(redist_base);
+out_unmap_dist:
+ iounmap(dist_base);
+ return err;
+}
+
+IRQCHIP_DECLARE(gic_v3, "arm,gic-v3", gic_of_init);