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authorLinus Torvalds <torvalds@linux-foundation.org>2014-12-16 04:30:09 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2014-12-16 04:30:09 +0300
commit60d7ef3fd34dca2eb7ef4c997ccf1ef76a9ba148 (patch)
treea5d9449b76af277c8f36008535c5d00036e021de /drivers/irqchip/irq-gic-v3-its.c
parent9b8ec916df67ba31614796037caf606b763e2e79 (diff)
parentc848126734e8621e81659d819922b20d93a2aa6d (diff)
downloadlinux-60d7ef3fd34dca2eb7ef4c997ccf1ef76a9ba148.tar.xz
Merge branch 'irq-irqdomain-arm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq domain ARM updates from Thomas Gleixner: "This set of changes make use of hierarchical irqdomains to provide: - MSI/ITS support for GICv3 - MSI support for GICv2m - Interrupt polarity extender for GICv1 Marc has come more cleanups for the existing extension hooks of GIC in the pipeline, but they are going to be 3.20 material" * 'irq-irqdomain-arm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits) irqchip: gicv3-its: Fix ITT allocation irqchip: gicv3-its: Move some alloc/free code to activate/deactivate irqchip: gicv3-its: Fix domain free in multi-MSI case irqchip: gic: Remove warning by including linux/irqdomain.h irqchip: gic-v2m: Add DT bindings for GICv2m irqchip: gic-v2m: Add support for ARM GICv2m MSI(-X) doorbell irqchip: mtk-sysirq: dt-bindings: Add bindings for mediatek sysirq irqchip: mtk-sysirq: Add sysirq interrupt polarity support irqchip: gic: Support hierarchy irq domain. irqchip: GICv3: Binding updates for ITS irqchip: GICv3: ITS: enable compilation of the ITS driver irqchip: GICv3: ITS: plug ITS init into main GICv3 code irqchip: GICv3: ITS: DT probing and initialization irqchip: GICv3: ITS: MSI support irqchip: GICv3: ITS: device allocation and configuration irqchip: GICv3: ITS: tables allocators irqchip: GICv3: ITS: LPI allocator irqchip: GICv3: ITS: irqchip implementation irqchip: GICv3: ITS command queue irqchip: GICv3: rework redistributor structure ...
Diffstat (limited to 'drivers/irqchip/irq-gic-v3-its.c')
-rw-r--r--drivers/irqchip/irq-gic-v3-its.c1425
1 files changed, 1425 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
new file mode 100644
index 000000000000..86e4684adeb1
--- /dev/null
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -0,0 +1,1425 @@
+/*
+ * 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/bitmap.h>
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/log2.h>
+#include <linux/mm.h>
+#include <linux/msi.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_pci.h>
+#include <linux/of_platform.h>
+#include <linux/percpu.h>
+#include <linux/slab.h>
+
+#include <linux/irqchip/arm-gic-v3.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cputype.h>
+#include <asm/exception.h>
+
+#include "irqchip.h"
+
+#define ITS_FLAGS_CMDQ_NEEDS_FLUSHING (1 << 0)
+
+#define RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING (1 << 0)
+
+/*
+ * Collection structure - just an ID, and a redistributor address to
+ * ping. We use one per CPU as a bag of interrupts assigned to this
+ * CPU.
+ */
+struct its_collection {
+ u64 target_address;
+ u16 col_id;
+};
+
+/*
+ * The ITS structure - contains most of the infrastructure, with the
+ * msi_controller, the command queue, the collections, and the list of
+ * devices writing to it.
+ */
+struct its_node {
+ raw_spinlock_t lock;
+ struct list_head entry;
+ struct msi_controller msi_chip;
+ struct irq_domain *domain;
+ void __iomem *base;
+ unsigned long phys_base;
+ struct its_cmd_block *cmd_base;
+ struct its_cmd_block *cmd_write;
+ void *tables[GITS_BASER_NR_REGS];
+ struct its_collection *collections;
+ struct list_head its_device_list;
+ u64 flags;
+ u32 ite_size;
+};
+
+#define ITS_ITT_ALIGN SZ_256
+
+/*
+ * The ITS view of a device - belongs to an ITS, a collection, owns an
+ * interrupt translation table, and a list of interrupts.
+ */
+struct its_device {
+ struct list_head entry;
+ struct its_node *its;
+ struct its_collection *collection;
+ void *itt;
+ unsigned long *lpi_map;
+ irq_hw_number_t lpi_base;
+ int nr_lpis;
+ u32 nr_ites;
+ u32 device_id;
+};
+
+static LIST_HEAD(its_nodes);
+static DEFINE_SPINLOCK(its_lock);
+static struct device_node *gic_root_node;
+static struct rdists *gic_rdists;
+
+#define gic_data_rdist() (raw_cpu_ptr(gic_rdists->rdist))
+#define gic_data_rdist_rd_base() (gic_data_rdist()->rd_base)
+
+/*
+ * ITS command descriptors - parameters to be encoded in a command
+ * block.
+ */
+struct its_cmd_desc {
+ union {
+ struct {
+ struct its_device *dev;
+ u32 event_id;
+ } its_inv_cmd;
+
+ struct {
+ struct its_device *dev;
+ u32 event_id;
+ } its_int_cmd;
+
+ struct {
+ struct its_device *dev;
+ int valid;
+ } its_mapd_cmd;
+
+ struct {
+ struct its_collection *col;
+ int valid;
+ } its_mapc_cmd;
+
+ struct {
+ struct its_device *dev;
+ u32 phys_id;
+ u32 event_id;
+ } its_mapvi_cmd;
+
+ struct {
+ struct its_device *dev;
+ struct its_collection *col;
+ u32 id;
+ } its_movi_cmd;
+
+ struct {
+ struct its_device *dev;
+ u32 event_id;
+ } its_discard_cmd;
+
+ struct {
+ struct its_collection *col;
+ } its_invall_cmd;
+ };
+};
+
+/*
+ * The ITS command block, which is what the ITS actually parses.
+ */
+struct its_cmd_block {
+ u64 raw_cmd[4];
+};
+
+#define ITS_CMD_QUEUE_SZ SZ_64K
+#define ITS_CMD_QUEUE_NR_ENTRIES (ITS_CMD_QUEUE_SZ / sizeof(struct its_cmd_block))
+
+typedef struct its_collection *(*its_cmd_builder_t)(struct its_cmd_block *,
+ struct its_cmd_desc *);
+
+static void its_encode_cmd(struct its_cmd_block *cmd, u8 cmd_nr)
+{
+ cmd->raw_cmd[0] &= ~0xffUL;
+ cmd->raw_cmd[0] |= cmd_nr;
+}
+
+static void its_encode_devid(struct its_cmd_block *cmd, u32 devid)
+{
+ cmd->raw_cmd[0] &= ~(0xffffUL << 32);
+ cmd->raw_cmd[0] |= ((u64)devid) << 32;
+}
+
+static void its_encode_event_id(struct its_cmd_block *cmd, u32 id)
+{
+ cmd->raw_cmd[1] &= ~0xffffffffUL;
+ cmd->raw_cmd[1] |= id;
+}
+
+static void its_encode_phys_id(struct its_cmd_block *cmd, u32 phys_id)
+{
+ cmd->raw_cmd[1] &= 0xffffffffUL;
+ cmd->raw_cmd[1] |= ((u64)phys_id) << 32;
+}
+
+static void its_encode_size(struct its_cmd_block *cmd, u8 size)
+{
+ cmd->raw_cmd[1] &= ~0x1fUL;
+ cmd->raw_cmd[1] |= size & 0x1f;
+}
+
+static void its_encode_itt(struct its_cmd_block *cmd, u64 itt_addr)
+{
+ cmd->raw_cmd[2] &= ~0xffffffffffffUL;
+ cmd->raw_cmd[2] |= itt_addr & 0xffffffffff00UL;
+}
+
+static void its_encode_valid(struct its_cmd_block *cmd, int valid)
+{
+ cmd->raw_cmd[2] &= ~(1UL << 63);
+ cmd->raw_cmd[2] |= ((u64)!!valid) << 63;
+}
+
+static void its_encode_target(struct its_cmd_block *cmd, u64 target_addr)
+{
+ cmd->raw_cmd[2] &= ~(0xffffffffUL << 16);
+ cmd->raw_cmd[2] |= (target_addr & (0xffffffffUL << 16));
+}
+
+static void its_encode_collection(struct its_cmd_block *cmd, u16 col)
+{
+ cmd->raw_cmd[2] &= ~0xffffUL;
+ cmd->raw_cmd[2] |= col;
+}
+
+static inline void its_fixup_cmd(struct its_cmd_block *cmd)
+{
+ /* Let's fixup BE commands */
+ cmd->raw_cmd[0] = cpu_to_le64(cmd->raw_cmd[0]);
+ cmd->raw_cmd[1] = cpu_to_le64(cmd->raw_cmd[1]);
+ cmd->raw_cmd[2] = cpu_to_le64(cmd->raw_cmd[2]);
+ cmd->raw_cmd[3] = cpu_to_le64(cmd->raw_cmd[3]);
+}
+
+static struct its_collection *its_build_mapd_cmd(struct its_cmd_block *cmd,
+ struct its_cmd_desc *desc)
+{
+ unsigned long itt_addr;
+ u8 size = ilog2(desc->its_mapd_cmd.dev->nr_ites);
+
+ itt_addr = virt_to_phys(desc->its_mapd_cmd.dev->itt);
+ itt_addr = ALIGN(itt_addr, ITS_ITT_ALIGN);
+
+ its_encode_cmd(cmd, GITS_CMD_MAPD);
+ its_encode_devid(cmd, desc->its_mapd_cmd.dev->device_id);
+ its_encode_size(cmd, size - 1);
+ its_encode_itt(cmd, itt_addr);
+ its_encode_valid(cmd, desc->its_mapd_cmd.valid);
+
+ its_fixup_cmd(cmd);
+
+ return desc->its_mapd_cmd.dev->collection;
+}
+
+static struct its_collection *its_build_mapc_cmd(struct its_cmd_block *cmd,
+ struct its_cmd_desc *desc)
+{
+ its_encode_cmd(cmd, GITS_CMD_MAPC);
+ its_encode_collection(cmd, desc->its_mapc_cmd.col->col_id);
+ its_encode_target(cmd, desc->its_mapc_cmd.col->target_address);
+ its_encode_valid(cmd, desc->its_mapc_cmd.valid);
+
+ its_fixup_cmd(cmd);
+
+ return desc->its_mapc_cmd.col;
+}
+
+static struct its_collection *its_build_mapvi_cmd(struct its_cmd_block *cmd,
+ struct its_cmd_desc *desc)
+{
+ its_encode_cmd(cmd, GITS_CMD_MAPVI);
+ its_encode_devid(cmd, desc->its_mapvi_cmd.dev->device_id);
+ its_encode_event_id(cmd, desc->its_mapvi_cmd.event_id);
+ its_encode_phys_id(cmd, desc->its_mapvi_cmd.phys_id);
+ its_encode_collection(cmd, desc->its_mapvi_cmd.dev->collection->col_id);
+
+ its_fixup_cmd(cmd);
+
+ return desc->its_mapvi_cmd.dev->collection;
+}
+
+static struct its_collection *its_build_movi_cmd(struct its_cmd_block *cmd,
+ struct its_cmd_desc *desc)
+{
+ its_encode_cmd(cmd, GITS_CMD_MOVI);
+ its_encode_devid(cmd, desc->its_movi_cmd.dev->device_id);
+ its_encode_event_id(cmd, desc->its_movi_cmd.id);
+ its_encode_collection(cmd, desc->its_movi_cmd.col->col_id);
+
+ its_fixup_cmd(cmd);
+
+ return desc->its_movi_cmd.dev->collection;
+}
+
+static struct its_collection *its_build_discard_cmd(struct its_cmd_block *cmd,
+ struct its_cmd_desc *desc)
+{
+ its_encode_cmd(cmd, GITS_CMD_DISCARD);
+ its_encode_devid(cmd, desc->its_discard_cmd.dev->device_id);
+ its_encode_event_id(cmd, desc->its_discard_cmd.event_id);
+
+ its_fixup_cmd(cmd);
+
+ return desc->its_discard_cmd.dev->collection;
+}
+
+static struct its_collection *its_build_inv_cmd(struct its_cmd_block *cmd,
+ struct its_cmd_desc *desc)
+{
+ its_encode_cmd(cmd, GITS_CMD_INV);
+ its_encode_devid(cmd, desc->its_inv_cmd.dev->device_id);
+ its_encode_event_id(cmd, desc->its_inv_cmd.event_id);
+
+ its_fixup_cmd(cmd);
+
+ return desc->its_inv_cmd.dev->collection;
+}
+
+static struct its_collection *its_build_invall_cmd(struct its_cmd_block *cmd,
+ struct its_cmd_desc *desc)
+{
+ its_encode_cmd(cmd, GITS_CMD_INVALL);
+ its_encode_collection(cmd, desc->its_mapc_cmd.col->col_id);
+
+ its_fixup_cmd(cmd);
+
+ return NULL;
+}
+
+static u64 its_cmd_ptr_to_offset(struct its_node *its,
+ struct its_cmd_block *ptr)
+{
+ return (ptr - its->cmd_base) * sizeof(*ptr);
+}
+
+static int its_queue_full(struct its_node *its)
+{
+ int widx;
+ int ridx;
+
+ widx = its->cmd_write - its->cmd_base;
+ ridx = readl_relaxed(its->base + GITS_CREADR) / sizeof(struct its_cmd_block);
+
+ /* This is incredibly unlikely to happen, unless the ITS locks up. */
+ if (((widx + 1) % ITS_CMD_QUEUE_NR_ENTRIES) == ridx)
+ return 1;
+
+ return 0;
+}
+
+static struct its_cmd_block *its_allocate_entry(struct its_node *its)
+{
+ struct its_cmd_block *cmd;
+ u32 count = 1000000; /* 1s! */
+
+ while (its_queue_full(its)) {
+ count--;
+ if (!count) {
+ pr_err_ratelimited("ITS queue not draining\n");
+ return NULL;
+ }
+ cpu_relax();
+ udelay(1);
+ }
+
+ cmd = its->cmd_write++;
+
+ /* Handle queue wrapping */
+ if (its->cmd_write == (its->cmd_base + ITS_CMD_QUEUE_NR_ENTRIES))
+ its->cmd_write = its->cmd_base;
+
+ return cmd;
+}
+
+static struct its_cmd_block *its_post_commands(struct its_node *its)
+{
+ u64 wr = its_cmd_ptr_to_offset(its, its->cmd_write);
+
+ writel_relaxed(wr, its->base + GITS_CWRITER);
+
+ return its->cmd_write;
+}
+
+static void its_flush_cmd(struct its_node *its, struct its_cmd_block *cmd)
+{
+ /*
+ * Make sure the commands written to memory are observable by
+ * the ITS.
+ */
+ if (its->flags & ITS_FLAGS_CMDQ_NEEDS_FLUSHING)
+ __flush_dcache_area(cmd, sizeof(*cmd));
+ else
+ dsb(ishst);
+}
+
+static void its_wait_for_range_completion(struct its_node *its,
+ struct its_cmd_block *from,
+ struct its_cmd_block *to)
+{
+ u64 rd_idx, from_idx, to_idx;
+ u32 count = 1000000; /* 1s! */
+
+ from_idx = its_cmd_ptr_to_offset(its, from);
+ to_idx = its_cmd_ptr_to_offset(its, to);
+
+ while (1) {
+ rd_idx = readl_relaxed(its->base + GITS_CREADR);
+ if (rd_idx >= to_idx || rd_idx < from_idx)
+ break;
+
+ count--;
+ if (!count) {
+ pr_err_ratelimited("ITS queue timeout\n");
+ return;
+ }
+ cpu_relax();
+ udelay(1);
+ }
+}
+
+static void its_send_single_command(struct its_node *its,
+ its_cmd_builder_t builder,
+ struct its_cmd_desc *desc)
+{
+ struct its_cmd_block *cmd, *sync_cmd, *next_cmd;
+ struct its_collection *sync_col;
+
+ raw_spin_lock(&its->lock);
+
+ cmd = its_allocate_entry(its);
+ if (!cmd) { /* We're soooooo screewed... */
+ pr_err_ratelimited("ITS can't allocate, dropping command\n");
+ raw_spin_unlock(&its->lock);
+ return;
+ }
+ sync_col = builder(cmd, desc);
+ its_flush_cmd(its, cmd);
+
+ if (sync_col) {
+ sync_cmd = its_allocate_entry(its);
+ if (!sync_cmd) {
+ pr_err_ratelimited("ITS can't SYNC, skipping\n");
+ goto post;
+ }
+ its_encode_cmd(sync_cmd, GITS_CMD_SYNC);
+ its_encode_target(sync_cmd, sync_col->target_address);
+ its_fixup_cmd(sync_cmd);
+ its_flush_cmd(its, sync_cmd);
+ }
+
+post:
+ next_cmd = its_post_commands(its);
+ raw_spin_unlock(&its->lock);
+
+ its_wait_for_range_completion(its, cmd, next_cmd);
+}
+
+static void its_send_inv(struct its_device *dev, u32 event_id)
+{
+ struct its_cmd_desc desc;
+
+ desc.its_inv_cmd.dev = dev;
+ desc.its_inv_cmd.event_id = event_id;
+
+ its_send_single_command(dev->its, its_build_inv_cmd, &desc);
+}
+
+static void its_send_mapd(struct its_device *dev, int valid)
+{
+ struct its_cmd_desc desc;
+
+ desc.its_mapd_cmd.dev = dev;
+ desc.its_mapd_cmd.valid = !!valid;
+
+ its_send_single_command(dev->its, its_build_mapd_cmd, &desc);
+}
+
+static void its_send_mapc(struct its_node *its, struct its_collection *col,
+ int valid)
+{
+ struct its_cmd_desc desc;
+
+ desc.its_mapc_cmd.col = col;
+ desc.its_mapc_cmd.valid = !!valid;
+
+ its_send_single_command(its, its_build_mapc_cmd, &desc);
+}
+
+static void its_send_mapvi(struct its_device *dev, u32 irq_id, u32 id)
+{
+ struct its_cmd_desc desc;
+
+ desc.its_mapvi_cmd.dev = dev;
+ desc.its_mapvi_cmd.phys_id = irq_id;
+ desc.its_mapvi_cmd.event_id = id;
+
+ its_send_single_command(dev->its, its_build_mapvi_cmd, &desc);
+}
+
+static void its_send_movi(struct its_device *dev,
+ struct its_collection *col, u32 id)
+{
+ struct its_cmd_desc desc;
+
+ desc.its_movi_cmd.dev = dev;
+ desc.its_movi_cmd.col = col;
+ desc.its_movi_cmd.id = id;
+
+ its_send_single_command(dev->its, its_build_movi_cmd, &desc);
+}
+
+static void its_send_discard(struct its_device *dev, u32 id)
+{
+ struct its_cmd_desc desc;
+
+ desc.its_discard_cmd.dev = dev;
+ desc.its_discard_cmd.event_id = id;
+
+ its_send_single_command(dev->its, its_build_discard_cmd, &desc);
+}
+
+static void its_send_invall(struct its_node *its, struct its_collection *col)
+{
+ struct its_cmd_desc desc;
+
+ desc.its_invall_cmd.col = col;
+
+ its_send_single_command(its, its_build_invall_cmd, &desc);
+}
+
+/*
+ * irqchip functions - assumes MSI, mostly.
+ */
+
+static inline u32 its_get_event_id(struct irq_data *d)
+{
+ struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+ return d->hwirq - its_dev->lpi_base;
+}
+
+static void lpi_set_config(struct irq_data *d, bool enable)
+{
+ struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+ irq_hw_number_t hwirq = d->hwirq;
+ u32 id = its_get_event_id(d);
+ u8 *cfg = page_address(gic_rdists->prop_page) + hwirq - 8192;
+
+ if (enable)
+ *cfg |= LPI_PROP_ENABLED;
+ else
+ *cfg &= ~LPI_PROP_ENABLED;
+
+ /*
+ * Make the above write visible to the redistributors.
+ * And yes, we're flushing exactly: One. Single. Byte.
+ * Humpf...
+ */
+ if (gic_rdists->flags & RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING)
+ __flush_dcache_area(cfg, sizeof(*cfg));
+ else
+ dsb(ishst);
+ its_send_inv(its_dev, id);
+}
+
+static void its_mask_irq(struct irq_data *d)
+{
+ lpi_set_config(d, false);
+}
+
+static void its_unmask_irq(struct irq_data *d)
+{
+ lpi_set_config(d, true);
+}
+
+static void its_eoi_irq(struct irq_data *d)
+{
+ gic_write_eoir(d->hwirq);
+}
+
+static int its_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
+ bool force)
+{
+ unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
+ struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+ struct its_collection *target_col;
+ u32 id = its_get_event_id(d);
+
+ if (cpu >= nr_cpu_ids)
+ return -EINVAL;
+
+ target_col = &its_dev->its->collections[cpu];
+ its_send_movi(its_dev, target_col, id);
+ its_dev->collection = target_col;
+
+ return IRQ_SET_MASK_OK_DONE;
+}
+
+static void its_irq_compose_msi_msg(struct irq_data *d, struct msi_msg *msg)
+{
+ struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+ struct its_node *its;
+ u64 addr;
+
+ its = its_dev->its;
+ addr = its->phys_base + GITS_TRANSLATER;
+
+ msg->address_lo = addr & ((1UL << 32) - 1);
+ msg->address_hi = addr >> 32;
+ msg->data = its_get_event_id(d);
+}
+
+static struct irq_chip its_irq_chip = {
+ .name = "ITS",
+ .irq_mask = its_mask_irq,
+ .irq_unmask = its_unmask_irq,
+ .irq_eoi = its_eoi_irq,
+ .irq_set_affinity = its_set_affinity,
+ .irq_compose_msi_msg = its_irq_compose_msi_msg,
+};
+
+static void its_mask_msi_irq(struct irq_data *d)
+{
+ pci_msi_mask_irq(d);
+ irq_chip_mask_parent(d);
+}
+
+static void its_unmask_msi_irq(struct irq_data *d)
+{
+ pci_msi_unmask_irq(d);
+ irq_chip_unmask_parent(d);
+}
+
+static struct irq_chip its_msi_irq_chip = {
+ .name = "ITS-MSI",
+ .irq_unmask = its_unmask_msi_irq,
+ .irq_mask = its_mask_msi_irq,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_write_msi_msg = pci_msi_domain_write_msg,
+};
+
+/*
+ * How we allocate LPIs:
+ *
+ * The GIC has id_bits bits for interrupt identifiers. From there, we
+ * must subtract 8192 which are reserved for SGIs/PPIs/SPIs. Then, as
+ * we allocate LPIs by chunks of 32, we can shift the whole thing by 5
+ * bits to the right.
+ *
+ * This gives us (((1UL << id_bits) - 8192) >> 5) possible allocations.
+ */
+#define IRQS_PER_CHUNK_SHIFT 5
+#define IRQS_PER_CHUNK (1 << IRQS_PER_CHUNK_SHIFT)
+
+static unsigned long *lpi_bitmap;
+static u32 lpi_chunks;
+static DEFINE_SPINLOCK(lpi_lock);
+
+static int its_lpi_to_chunk(int lpi)
+{
+ return (lpi - 8192) >> IRQS_PER_CHUNK_SHIFT;
+}
+
+static int its_chunk_to_lpi(int chunk)
+{
+ return (chunk << IRQS_PER_CHUNK_SHIFT) + 8192;
+}
+
+static int its_lpi_init(u32 id_bits)
+{
+ lpi_chunks = its_lpi_to_chunk(1UL << id_bits);
+
+ lpi_bitmap = kzalloc(BITS_TO_LONGS(lpi_chunks) * sizeof(long),
+ GFP_KERNEL);
+ if (!lpi_bitmap) {
+ lpi_chunks = 0;
+ return -ENOMEM;
+ }
+
+ pr_info("ITS: Allocated %d chunks for LPIs\n", (int)lpi_chunks);
+ return 0;
+}
+
+static unsigned long *its_lpi_alloc_chunks(int nr_irqs, int *base, int *nr_ids)
+{
+ unsigned long *bitmap = NULL;
+ int chunk_id;
+ int nr_chunks;
+ int i;
+
+ nr_chunks = DIV_ROUND_UP(nr_irqs, IRQS_PER_CHUNK);
+
+ spin_lock(&lpi_lock);
+
+ do {
+ chunk_id = bitmap_find_next_zero_area(lpi_bitmap, lpi_chunks,
+ 0, nr_chunks, 0);
+ if (chunk_id < lpi_chunks)
+ break;
+
+ nr_chunks--;
+ } while (nr_chunks > 0);
+
+ if (!nr_chunks)
+ goto out;
+
+ bitmap = kzalloc(BITS_TO_LONGS(nr_chunks * IRQS_PER_CHUNK) * sizeof (long),
+ GFP_ATOMIC);
+ if (!bitmap)
+ goto out;
+
+ for (i = 0; i < nr_chunks; i++)
+ set_bit(chunk_id + i, lpi_bitmap);
+
+ *base = its_chunk_to_lpi(chunk_id);
+ *nr_ids = nr_chunks * IRQS_PER_CHUNK;
+
+out:
+ spin_unlock(&lpi_lock);
+
+ return bitmap;
+}
+
+static void its_lpi_free(unsigned long *bitmap, int base, int nr_ids)
+{
+ int lpi;
+
+ spin_lock(&lpi_lock);
+
+ for (lpi = base; lpi < (base + nr_ids); lpi += IRQS_PER_CHUNK) {
+ int chunk = its_lpi_to_chunk(lpi);
+ BUG_ON(chunk > lpi_chunks);
+ if (test_bit(chunk, lpi_bitmap)) {
+ clear_bit(chunk, lpi_bitmap);
+ } else {
+ pr_err("Bad LPI chunk %d\n", chunk);
+ }
+ }
+
+ spin_unlock(&lpi_lock);
+
+ kfree(bitmap);
+}
+
+/*
+ * We allocate 64kB for PROPBASE. That gives us at most 64K LPIs to
+ * deal with (one configuration byte per interrupt). PENDBASE has to
+ * be 64kB aligned (one bit per LPI, plus 8192 bits for SPI/PPI/SGI).
+ */
+#define LPI_PROPBASE_SZ SZ_64K
+#define LPI_PENDBASE_SZ (LPI_PROPBASE_SZ / 8 + SZ_1K)
+
+/*
+ * This is how many bits of ID we need, including the useless ones.
+ */
+#define LPI_NRBITS ilog2(LPI_PROPBASE_SZ + SZ_8K)
+
+#define LPI_PROP_DEFAULT_PRIO 0xa0
+
+static int __init its_alloc_lpi_tables(void)
+{
+ phys_addr_t paddr;
+
+ gic_rdists->prop_page = alloc_pages(GFP_NOWAIT,
+ get_order(LPI_PROPBASE_SZ));
+ if (!gic_rdists->prop_page) {
+ pr_err("Failed to allocate PROPBASE\n");
+ return -ENOMEM;
+ }
+
+ paddr = page_to_phys(gic_rdists->prop_page);
+ pr_info("GIC: using LPI property table @%pa\n", &paddr);
+
+ /* Priority 0xa0, Group-1, disabled */
+ memset(page_address(gic_rdists->prop_page),
+ LPI_PROP_DEFAULT_PRIO | LPI_PROP_GROUP1,
+ LPI_PROPBASE_SZ);
+
+ /* Make sure the GIC will observe the written configuration */
+ __flush_dcache_area(page_address(gic_rdists->prop_page), LPI_PROPBASE_SZ);
+
+ return 0;
+}
+
+static const char *its_base_type_string[] = {
+ [GITS_BASER_TYPE_DEVICE] = "Devices",
+ [GITS_BASER_TYPE_VCPU] = "Virtual CPUs",
+ [GITS_BASER_TYPE_CPU] = "Physical CPUs",
+ [GITS_BASER_TYPE_COLLECTION] = "Interrupt Collections",
+ [GITS_BASER_TYPE_RESERVED5] = "Reserved (5)",
+ [GITS_BASER_TYPE_RESERVED6] = "Reserved (6)",
+ [GITS_BASER_TYPE_RESERVED7] = "Reserved (7)",
+};
+
+static void its_free_tables(struct its_node *its)
+{
+ int i;
+
+ for (i = 0; i < GITS_BASER_NR_REGS; i++) {
+ if (its->tables[i]) {
+ free_page((unsigned long)its->tables[i]);
+ its->tables[i] = NULL;
+ }
+ }
+}
+
+static int its_alloc_tables(struct its_node *its)
+{
+ int err;
+ int i;
+ int psz = PAGE_SIZE;
+ u64 shr = GITS_BASER_InnerShareable;
+
+ for (i = 0; i < GITS_BASER_NR_REGS; i++) {
+ u64 val = readq_relaxed(its->base + GITS_BASER + i * 8);
+ u64 type = GITS_BASER_TYPE(val);
+ u64 entry_size = GITS_BASER_ENTRY_SIZE(val);
+ u64 tmp;
+ void *base;
+
+ if (type == GITS_BASER_TYPE_NONE)
+ continue;
+
+ /* We're lazy and only allocate a single page for now */
+ base = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!base) {
+ err = -ENOMEM;
+ goto out_free;
+ }
+
+ its->tables[i] = base;
+
+retry_baser:
+ val = (virt_to_phys(base) |
+ (type << GITS_BASER_TYPE_SHIFT) |
+ ((entry_size - 1) << GITS_BASER_ENTRY_SIZE_SHIFT) |
+ GITS_BASER_WaWb |
+ shr |
+ GITS_BASER_VALID);
+
+ switch (psz) {
+ case SZ_4K:
+ val |= GITS_BASER_PAGE_SIZE_4K;
+ break;
+ case SZ_16K:
+ val |= GITS_BASER_PAGE_SIZE_16K;
+ break;
+ case SZ_64K:
+ val |= GITS_BASER_PAGE_SIZE_64K;
+ break;
+ }
+
+ val |= (PAGE_SIZE / psz) - 1;
+
+ writeq_relaxed(val, its->base + GITS_BASER + i * 8);
+ tmp = readq_relaxed(its->base + GITS_BASER + i * 8);
+
+ if ((val ^ tmp) & GITS_BASER_SHAREABILITY_MASK) {
+ /*
+ * Shareability didn't stick. Just use
+ * whatever the read reported, which is likely
+ * to be the only thing this redistributor
+ * supports.
+ */
+ shr = tmp & GITS_BASER_SHAREABILITY_MASK;
+ goto retry_baser;
+ }
+
+ if ((val ^ tmp) & GITS_BASER_PAGE_SIZE_MASK) {
+ /*
+ * Page size didn't stick. Let's try a smaller
+ * size and retry. If we reach 4K, then
+ * something is horribly wrong...
+ */
+ switch (psz) {
+ case SZ_16K:
+ psz = SZ_4K;
+ goto retry_baser;
+ case SZ_64K:
+ psz = SZ_16K;
+ goto retry_baser;
+ }
+ }
+
+ if (val != tmp) {
+ pr_err("ITS: %s: GITS_BASER%d doesn't stick: %lx %lx\n",
+ its->msi_chip.of_node->full_name, i,
+ (unsigned long) val, (unsigned long) tmp);
+ err = -ENXIO;
+ goto out_free;
+ }
+
+ pr_info("ITS: allocated %d %s @%lx (psz %dK, shr %d)\n",
+ (int)(PAGE_SIZE / entry_size),
+ its_base_type_string[type],
+ (unsigned long)virt_to_phys(base),
+ psz / SZ_1K, (int)shr >> GITS_BASER_SHAREABILITY_SHIFT);
+ }
+
+ return 0;
+
+out_free:
+ its_free_tables(its);
+
+ return err;
+}
+
+static int its_alloc_collections(struct its_node *its)
+{
+ its->collections = kzalloc(nr_cpu_ids * sizeof(*its->collections),
+ GFP_KERNEL);
+ if (!its->collections)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void its_cpu_init_lpis(void)
+{
+ void __iomem *rbase = gic_data_rdist_rd_base();
+ struct page *pend_page;
+ u64 val, tmp;
+
+ /* If we didn't allocate the pending table yet, do it now */
+ pend_page = gic_data_rdist()->pend_page;
+ if (!pend_page) {
+ phys_addr_t paddr;
+ /*
+ * The pending pages have to be at least 64kB aligned,
+ * hence the 'max(LPI_PENDBASE_SZ, SZ_64K)' below.
+ */
+ pend_page = alloc_pages(GFP_NOWAIT | __GFP_ZERO,
+ get_order(max(LPI_PENDBASE_SZ, SZ_64K)));
+ if (!pend_page) {
+ pr_err("Failed to allocate PENDBASE for CPU%d\n",
+ smp_processor_id());
+ return;
+ }
+
+ /* Make sure the GIC will observe the zero-ed page */
+ __flush_dcache_area(page_address(pend_page), LPI_PENDBASE_SZ);
+
+ paddr = page_to_phys(pend_page);
+ pr_info("CPU%d: using LPI pending table @%pa\n",
+ smp_processor_id(), &paddr);
+ gic_data_rdist()->pend_page = pend_page;
+ }
+
+ /* Disable LPIs */
+ val = readl_relaxed(rbase + GICR_CTLR);
+ val &= ~GICR_CTLR_ENABLE_LPIS;
+ writel_relaxed(val, rbase + GICR_CTLR);
+
+ /*
+ * Make sure any change to the table is observable by the GIC.
+ */
+ dsb(sy);
+
+ /* set PROPBASE */
+ val = (page_to_phys(gic_rdists->prop_page) |
+ GICR_PROPBASER_InnerShareable |
+ GICR_PROPBASER_WaWb |
+ ((LPI_NRBITS - 1) & GICR_PROPBASER_IDBITS_MASK));
+
+ writeq_relaxed(val, rbase + GICR_PROPBASER);
+ tmp = readq_relaxed(rbase + GICR_PROPBASER);
+
+ if ((tmp ^ val) & GICR_PROPBASER_SHAREABILITY_MASK) {
+ pr_info_once("GIC: using cache flushing for LPI property table\n");
+ gic_rdists->flags |= RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING;
+ }
+
+ /* set PENDBASE */
+ val = (page_to_phys(pend_page) |
+ GICR_PROPBASER_InnerShareable |
+ GICR_PROPBASER_WaWb);
+
+ writeq_relaxed(val, rbase + GICR_PENDBASER);
+
+ /* Enable LPIs */
+ val = readl_relaxed(rbase + GICR_CTLR);
+ val |= GICR_CTLR_ENABLE_LPIS;
+ writel_relaxed(val, rbase + GICR_CTLR);
+
+ /* Make sure the GIC has seen the above */
+ dsb(sy);
+}
+
+static void its_cpu_init_collection(void)
+{
+ struct its_node *its;
+ int cpu;
+
+ spin_lock(&its_lock);
+ cpu = smp_processor_id();
+
+ list_for_each_entry(its, &its_nodes, entry) {
+ u64 target;
+
+ /*
+ * We now have to bind each collection to its target
+ * redistributor.
+ */
+ if (readq_relaxed(its->base + GITS_TYPER) & GITS_TYPER_PTA) {
+ /*
+ * This ITS wants the physical address of the
+ * redistributor.
+ */
+ target = gic_data_rdist()->phys_base;
+ } else {
+ /*
+ * This ITS wants a linear CPU number.
+ */
+ target = readq_relaxed(gic_data_rdist_rd_base() + GICR_TYPER);
+ target = GICR_TYPER_CPU_NUMBER(target);
+ }
+
+ /* Perform collection mapping */
+ its->collections[cpu].target_address = target;
+ its->collections[cpu].col_id = cpu;
+
+ its_send_mapc(its, &its->collections[cpu], 1);
+ its_send_invall(its, &its->collections[cpu]);
+ }
+
+ spin_unlock(&its_lock);
+}
+
+static struct its_device *its_find_device(struct its_node *its, u32 dev_id)
+{
+ struct its_device *its_dev = NULL, *tmp;
+
+ raw_spin_lock(&its->lock);
+
+ list_for_each_entry(tmp, &its->its_device_list, entry) {
+ if (tmp->device_id == dev_id) {
+ its_dev = tmp;
+ break;
+ }
+ }
+
+ raw_spin_unlock(&its->lock);
+
+ return its_dev;
+}
+
+static struct its_device *its_create_device(struct its_node *its, u32 dev_id,
+ int nvecs)
+{
+ struct its_device *dev;
+ unsigned long *lpi_map;
+ void *itt;
+ int lpi_base;
+ int nr_lpis;
+ int nr_ites;
+ int cpu;
+ int sz;
+
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ /*
+ * At least one bit of EventID is being used, hence a minimum
+ * of two entries. No, the architecture doesn't let you
+ * express an ITT with a single entry.
+ */
+ nr_ites = max(2, roundup_pow_of_two(nvecs));
+ sz = nr_ites * its->ite_size;
+ sz = max(sz, ITS_ITT_ALIGN) + ITS_ITT_ALIGN - 1;
+ itt = kmalloc(sz, GFP_KERNEL);
+ lpi_map = its_lpi_alloc_chunks(nvecs, &lpi_base, &nr_lpis);
+
+ if (!dev || !itt || !lpi_map) {
+ kfree(dev);
+ kfree(itt);
+ kfree(lpi_map);
+ return NULL;
+ }
+
+ dev->its = its;
+ dev->itt = itt;
+ dev->nr_ites = nr_ites;
+ dev->lpi_map = lpi_map;
+ dev->lpi_base = lpi_base;
+ dev->nr_lpis = nr_lpis;
+ dev->device_id = dev_id;
+ INIT_LIST_HEAD(&dev->entry);
+
+ raw_spin_lock(&its->lock);
+ list_add(&dev->entry, &its->its_device_list);
+ raw_spin_unlock(&its->lock);
+
+ /* Bind the device to the first possible CPU */
+ cpu = cpumask_first(cpu_online_mask);
+ dev->collection = &its->collections[cpu];
+
+ /* Map device to its ITT */
+ its_send_mapd(dev, 1);
+
+ return dev;
+}
+
+static void its_free_device(struct its_device *its_dev)
+{
+ raw_spin_lock(&its_dev->its->lock);
+ list_del(&its_dev->entry);
+ raw_spin_unlock(&its_dev->its->lock);
+ kfree(its_dev->itt);
+ kfree(its_dev);
+}
+
+static int its_alloc_device_irq(struct its_device *dev, irq_hw_number_t *hwirq)
+{
+ int idx;
+
+ idx = find_first_zero_bit(dev->lpi_map, dev->nr_lpis);
+ if (idx == dev->nr_lpis)
+ return -ENOSPC;
+
+ *hwirq = dev->lpi_base + idx;
+ set_bit(idx, dev->lpi_map);
+
+ return 0;
+}
+
+static int its_msi_prepare(struct irq_domain *domain, struct device *dev,
+ int nvec, msi_alloc_info_t *info)
+{
+ struct pci_dev *pdev;
+ struct its_node *its;
+ u32 dev_id;
+ struct its_device *its_dev;
+
+ if (!dev_is_pci(dev))
+ return -EINVAL;
+
+ pdev = to_pci_dev(dev);
+ dev_id = PCI_DEVID(pdev->bus->number, pdev->devfn);
+ its = domain->parent->host_data;
+
+ its_dev = its_find_device(its, dev_id);
+ if (WARN_ON(its_dev))
+ return -EINVAL;
+
+ its_dev = its_create_device(its, dev_id, nvec);
+ if (!its_dev)
+ return -ENOMEM;
+
+ dev_dbg(&pdev->dev, "ITT %d entries, %d bits\n", nvec, ilog2(nvec));
+
+ info->scratchpad[0].ptr = its_dev;
+ info->scratchpad[1].ptr = dev;
+ return 0;
+}
+
+static struct msi_domain_ops its_pci_msi_ops = {
+ .msi_prepare = its_msi_prepare,
+};
+
+static struct msi_domain_info its_pci_msi_domain_info = {
+ .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+ MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX),
+ .ops = &its_pci_msi_ops,
+ .chip = &its_msi_irq_chip,
+};
+
+static int its_irq_gic_domain_alloc(struct irq_domain *domain,
+ unsigned int virq,
+ irq_hw_number_t hwirq)
+{
+ struct of_phandle_args args;
+
+ args.np = domain->parent->of_node;
+ args.args_count = 3;
+ args.args[0] = GIC_IRQ_TYPE_LPI;
+ args.args[1] = hwirq;
+ args.args[2] = IRQ_TYPE_EDGE_RISING;
+
+ return irq_domain_alloc_irqs_parent(domain, virq, 1, &args);
+}
+
+static int its_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *args)
+{
+ msi_alloc_info_t *info = args;
+ struct its_device *its_dev = info->scratchpad[0].ptr;
+ irq_hw_number_t hwirq;
+ int err;
+ int i;
+
+ for (i = 0; i < nr_irqs; i++) {
+ err = its_alloc_device_irq(its_dev, &hwirq);
+ if (err)
+ return err;
+
+ err = its_irq_gic_domain_alloc(domain, virq + i, hwirq);
+ if (err)
+ return err;
+
+ irq_domain_set_hwirq_and_chip(domain, virq + i,
+ hwirq, &its_irq_chip, its_dev);
+ dev_dbg(info->scratchpad[1].ptr, "ID:%d pID:%d vID:%d\n",
+ (int)(hwirq - its_dev->lpi_base), (int)hwirq, virq + i);
+ }
+
+ return 0;
+}
+
+static void its_irq_domain_activate(struct irq_domain *domain,
+ struct irq_data *d)
+{
+ struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+ u32 event = its_get_event_id(d);
+
+ /* Map the GIC IRQ and event to the device */
+ its_send_mapvi(its_dev, d->hwirq, event);
+}
+
+static void its_irq_domain_deactivate(struct irq_domain *domain,
+ struct irq_data *d)
+{
+ struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+ u32 event = its_get_event_id(d);
+
+ /* Stop the delivery of interrupts */
+ its_send_discard(its_dev, event);
+}
+
+static void its_irq_domain_free(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ struct irq_data *d = irq_domain_get_irq_data(domain, virq);
+ struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+ int i;
+
+ for (i = 0; i < nr_irqs; i++) {
+ struct irq_data *data = irq_domain_get_irq_data(domain,
+ virq + i);
+ u32 event = its_get_event_id(data);
+
+ /* Mark interrupt index as unused */
+ clear_bit(event, its_dev->lpi_map);
+
+ /* Nuke the entry in the domain */
+ irq_domain_reset_irq_data(data);
+ }
+
+ /* If all interrupts have been freed, start mopping the floor */
+ if (bitmap_empty(its_dev->lpi_map, its_dev->nr_lpis)) {
+ its_lpi_free(its_dev->lpi_map,
+ its_dev->lpi_base,
+ its_dev->nr_lpis);
+
+ /* Unmap device/itt */
+ its_send_mapd(its_dev, 0);
+ its_free_device(its_dev);
+ }
+
+ irq_domain_free_irqs_parent(domain, virq, nr_irqs);
+}
+
+static const struct irq_domain_ops its_domain_ops = {
+ .alloc = its_irq_domain_alloc,
+ .free = its_irq_domain_free,
+ .activate = its_irq_domain_activate,
+ .deactivate = its_irq_domain_deactivate,
+};
+
+static int its_probe(struct device_node *node, struct irq_domain *parent)
+{
+ struct resource res;
+ struct its_node *its;
+ void __iomem *its_base;
+ u32 val;
+ u64 baser, tmp;
+ int err;
+
+ err = of_address_to_resource(node, 0, &res);
+ if (err) {
+ pr_warn("%s: no regs?\n", node->full_name);
+ return -ENXIO;
+ }
+
+ its_base = ioremap(res.start, resource_size(&res));
+ if (!its_base) {
+ pr_warn("%s: unable to map registers\n", node->full_name);
+ return -ENOMEM;
+ }
+
+ val = readl_relaxed(its_base + GITS_PIDR2) & GIC_PIDR2_ARCH_MASK;
+ if (val != 0x30 && val != 0x40) {
+ pr_warn("%s: no ITS detected, giving up\n", node->full_name);
+ err = -ENODEV;
+ goto out_unmap;
+ }
+
+ pr_info("ITS: %s\n", node->full_name);
+
+ its = kzalloc(sizeof(*its), GFP_KERNEL);
+ if (!its) {
+ err = -ENOMEM;
+ goto out_unmap;
+ }
+
+ raw_spin_lock_init(&its->lock);
+ INIT_LIST_HEAD(&its->entry);
+ INIT_LIST_HEAD(&its->its_device_list);
+ its->base = its_base;
+ its->phys_base = res.start;
+ its->msi_chip.of_node = node;
+ its->ite_size = ((readl_relaxed(its_base + GITS_TYPER) >> 4) & 0xf) + 1;
+
+ its->cmd_base = kzalloc(ITS_CMD_QUEUE_SZ, GFP_KERNEL);
+ if (!its->cmd_base) {
+ err = -ENOMEM;
+ goto out_free_its;
+ }
+ its->cmd_write = its->cmd_base;
+
+ err = its_alloc_tables(its);
+ if (err)
+ goto out_free_cmd;
+
+ err = its_alloc_collections(its);
+ if (err)
+ goto out_free_tables;
+
+ baser = (virt_to_phys(its->cmd_base) |
+ GITS_CBASER_WaWb |
+ GITS_CBASER_InnerShareable |
+ (ITS_CMD_QUEUE_SZ / SZ_4K - 1) |
+ GITS_CBASER_VALID);
+
+ writeq_relaxed(baser, its->base + GITS_CBASER);
+ tmp = readq_relaxed(its->base + GITS_CBASER);
+ writeq_relaxed(0, its->base + GITS_CWRITER);
+ writel_relaxed(1, its->base + GITS_CTLR);
+
+ if ((tmp ^ baser) & GITS_BASER_SHAREABILITY_MASK) {
+ pr_info("ITS: using cache flushing for cmd queue\n");
+ its->flags |= ITS_FLAGS_CMDQ_NEEDS_FLUSHING;
+ }
+
+ if (of_property_read_bool(its->msi_chip.of_node, "msi-controller")) {
+ its->domain = irq_domain_add_tree(NULL, &its_domain_ops, its);
+ if (!its->domain) {
+ err = -ENOMEM;
+ goto out_free_tables;
+ }
+
+ its->domain->parent = parent;
+
+ its->msi_chip.domain = pci_msi_create_irq_domain(node,
+ &its_pci_msi_domain_info,
+ its->domain);
+ if (!its->msi_chip.domain) {
+ err = -ENOMEM;
+ goto out_free_domains;
+ }
+
+ err = of_pci_msi_chip_add(&its->msi_chip);
+ if (err)
+ goto out_free_domains;
+ }
+
+ spin_lock(&its_lock);
+ list_add(&its->entry, &its_nodes);
+ spin_unlock(&its_lock);
+
+ return 0;
+
+out_free_domains:
+ if (its->msi_chip.domain)
+ irq_domain_remove(its->msi_chip.domain);
+ if (its->domain)
+ irq_domain_remove(its->domain);
+out_free_tables:
+ its_free_tables(its);
+out_free_cmd:
+ kfree(its->cmd_base);
+out_free_its:
+ kfree(its);
+out_unmap:
+ iounmap(its_base);
+ pr_err("ITS: failed probing %s (%d)\n", node->full_name, err);
+ return err;
+}
+
+static bool gic_rdists_supports_plpis(void)
+{
+ return !!(readl_relaxed(gic_data_rdist_rd_base() + GICR_TYPER) & GICR_TYPER_PLPIS);
+}
+
+int its_cpu_init(void)
+{
+ if (!gic_rdists_supports_plpis()) {
+ pr_info("CPU%d: LPIs not supported\n", smp_processor_id());
+ return -ENXIO;
+ }
+
+ if (!list_empty(&its_nodes)) {
+ its_cpu_init_lpis();
+ its_cpu_init_collection();
+ }
+
+ return 0;
+}
+
+static struct of_device_id its_device_id[] = {
+ { .compatible = "arm,gic-v3-its", },
+ {},
+};
+
+int its_init(struct device_node *node, struct rdists *rdists,
+ struct irq_domain *parent_domain)
+{
+ struct device_node *np;
+
+ for (np = of_find_matching_node(node, its_device_id); np;
+ np = of_find_matching_node(np, its_device_id)) {
+ its_probe(np, parent_domain);
+ }
+
+ if (list_empty(&its_nodes)) {
+ pr_warn("ITS: No ITS available, not enabling LPIs\n");
+ return -ENXIO;
+ }
+
+ gic_rdists = rdists;
+ gic_root_node = node;
+
+ its_alloc_lpi_tables();
+ its_lpi_init(rdists->id_bits);
+
+ return 0;
+}