/* * Copyright (C) 2013, 2014 ARM Limited, All Rights Reserved. * Author: Marc Zyngier * * 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 . */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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 struct event_lpi_map { unsigned long *lpi_map; u16 *col_map; irq_hw_number_t lpi_base; int nr_lpis; }; /* * 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 event_lpi_map event_map; void *itt; 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) static struct its_collection *dev_event_to_col(struct its_device *its_dev, u32 event) { struct its_node *its = its_dev->its; return its->collections + its_dev->event_map.col_map[event]; } /* * 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 event_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] &= BIT_ULL(32) - 1; 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 NULL; } 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) { struct its_collection *col; col = dev_event_to_col(desc->its_mapvi_cmd.dev, desc->its_mapvi_cmd.event_id); 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, col->col_id); its_fixup_cmd(cmd); return col; } static struct its_collection *its_build_movi_cmd(struct its_cmd_block *cmd, struct its_cmd_desc *desc) { struct its_collection *col; col = dev_event_to_col(desc->its_movi_cmd.dev, desc->its_movi_cmd.event_id); 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.event_id); its_encode_collection(cmd, desc->its_movi_cmd.col->col_id); its_fixup_cmd(cmd); return col; } static struct its_collection *its_build_discard_cmd(struct its_cmd_block *cmd, struct its_cmd_desc *desc) { struct its_collection *col; col = dev_event_to_col(desc->its_discard_cmd.dev, desc->its_discard_cmd.event_id); 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 col; } static struct its_collection *its_build_inv_cmd(struct its_cmd_block *cmd, struct its_cmd_desc *desc) { struct its_collection *col; col = dev_event_to_col(desc->its_inv_cmd.dev, desc->its_inv_cmd.event_id); 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 col; } 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; unsigned long flags; raw_spin_lock_irqsave(&its->lock, flags); cmd = its_allocate_entry(its); if (!cmd) { /* We're soooooo screewed... */ pr_err_ratelimited("ITS can't allocate, dropping command\n"); raw_spin_unlock_irqrestore(&its->lock, flags); 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_irqrestore(&its->lock, flags); 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.event_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->event_map.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->event_map.col_map[id] = cpu; 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, }; /* * 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(struct event_lpi_map *map) { int base = map->lpi_base; int nr_ids = map->nr_lpis; 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(map->lpi_map); kfree(map->col_map); } /* * 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 = SZ_64K; u64 shr = GITS_BASER_InnerShareable; u64 cache = GITS_BASER_WaWb; 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); int order = get_order(psz); int alloc_size; u64 tmp; void *base; if (type == GITS_BASER_TYPE_NONE) continue; /* * Allocate as many entries as required to fit the * range of device IDs that the ITS can grok... The ID * space being incredibly sparse, this results in a * massive waste of memory. * * For other tables, only allocate a single page. */ if (type == GITS_BASER_TYPE_DEVICE) { u64 typer = readq_relaxed(its->base + GITS_TYPER); u32 ids = GITS_TYPER_DEVBITS(typer); /* * 'order' was initialized earlier to the default page * granule of the the ITS. We can't have an allocation * smaller than that. If the requested allocation * is smaller, round up to the default page granule. */ order = max(get_order((1UL << ids) * entry_size), order); if (order >= MAX_ORDER) { order = MAX_ORDER - 1; pr_warn("%s: Device Table too large, reduce its page order to %u\n", its->msi_chip.of_node->full_name, order); } } alloc_size = (1 << order) * PAGE_SIZE; base = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 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) | cache | 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 |= (alloc_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. If that's zero, make it * non-cacheable as well. */ shr = tmp & GITS_BASER_SHAREABILITY_MASK; if (!shr) cache = GITS_BASER_nC; 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)(alloc_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) { if (!(tmp & GICR_PROPBASER_SHAREABILITY_MASK)) { /* * The HW reports non-shareable, we must * remove the cacheability attributes as * well. */ val &= ~(GICR_PROPBASER_SHAREABILITY_MASK | GICR_PROPBASER_CACHEABILITY_MASK); val |= GICR_PROPBASER_nC; writeq_relaxed(val, rbase + GICR_PROPBASER); } 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_PENDBASER_InnerShareable | GICR_PENDBASER_WaWb); writeq_relaxed(val, rbase + GICR_PENDBASER); tmp = readq_relaxed(rbase + GICR_PENDBASER); if (!(tmp & GICR_PENDBASER_SHAREABILITY_MASK)) { /* * The HW reports non-shareable, we must remove the * cacheability attributes as well. */ val &= ~(GICR_PENDBASER_SHAREABILITY_MASK | GICR_PENDBASER_CACHEABILITY_MASK); val |= GICR_PENDBASER_nC; 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) << 16; } /* 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; unsigned long flags; raw_spin_lock_irqsave(&its->lock, flags); list_for_each_entry(tmp, &its->its_device_list, entry) { if (tmp->device_id == dev_id) { its_dev = tmp; break; } } raw_spin_unlock_irqrestore(&its->lock, flags); 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; unsigned long flags; u16 *col_map = NULL; void *itt; int lpi_base; int nr_lpis; int nr_ites; 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(2UL, roundup_pow_of_two(nvecs)); sz = nr_ites * its->ite_size; sz = max(sz, ITS_ITT_ALIGN) + ITS_ITT_ALIGN - 1; itt = kzalloc(sz, GFP_KERNEL); lpi_map = its_lpi_alloc_chunks(nvecs, &lpi_base, &nr_lpis); if (lpi_map) col_map = kzalloc(sizeof(*col_map) * nr_lpis, GFP_KERNEL); if (!dev || !itt || !lpi_map || !col_map) { kfree(dev); kfree(itt); kfree(lpi_map); kfree(col_map); return NULL; } dev->its = its; dev->itt = itt; dev->nr_ites = nr_ites; dev->event_map.lpi_map = lpi_map; dev->event_map.col_map = col_map; dev->event_map.lpi_base = lpi_base; dev->event_map.nr_lpis = nr_lpis; dev->device_id = dev_id; INIT_LIST_HEAD(&dev->entry); raw_spin_lock_irqsave(&its->lock, flags); list_add(&dev->entry, &its->its_device_list); raw_spin_unlock_irqrestore(&its->lock, flags); /* Map device to its ITT */ its_send_mapd(dev, 1); return dev; } static void its_free_device(struct its_device *its_dev) { unsigned long flags; raw_spin_lock_irqsave(&its_dev->its->lock, flags); list_del(&its_dev->entry); raw_spin_unlock_irqrestore(&its_dev->its->lock, flags); 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->event_map.lpi_map, dev->event_map.nr_lpis); if (idx == dev->event_map.nr_lpis) return -ENOSPC; *hwirq = dev->event_map.lpi_base + idx; set_bit(idx, dev->event_map.lpi_map); return 0; } int its_msi_prepare(struct irq_domain *domain, u32 dev_id, int nvec, msi_alloc_info_t *info) { struct its_node *its; struct its_device *its_dev; its = domain->parent->host_data; its_dev = its_find_device(its, dev_id); if (its_dev) { /* * We already have seen this ID, probably through * another alias (PCI bridge of some sort). No need to * create the device. */ pr_debug("Reusing ITT for devID %x\n", dev_id); goto out; } its_dev = its_create_device(its, dev_id, nvec); if (!its_dev) return -ENOMEM; pr_debug("ITT %d entries, %d bits\n", nvec, ilog2(nvec)); out: info->scratchpad[0].ptr = its_dev; return 0; } 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); pr_debug("ID:%d pID:%d vID:%d\n", (int)(hwirq - its_dev->event_map.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); /* Bind the LPI to the first possible CPU */ its_dev->event_map.col_map[event] = cpumask_first(cpu_online_mask); /* 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->event_map.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->event_map.lpi_map, its_dev->event_map.nr_lpis)) { its_lpi_free(&its_dev->event_map); /* 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_force_quiescent(void __iomem *base) { u32 count = 1000000; /* 1s */ u32 val; val = readl_relaxed(base + GITS_CTLR); if (val & GITS_CTLR_QUIESCENT) return 0; /* Disable the generation of all interrupts to this ITS */ val &= ~GITS_CTLR_ENABLE; writel_relaxed(val, base + GITS_CTLR); /* Poll GITS_CTLR and wait until ITS becomes quiescent */ while (1) { val = readl_relaxed(base + GITS_CTLR); if (val & GITS_CTLR_QUIESCENT) return 0; count--; if (!count) return -EBUSY; cpu_relax(); udelay(1); } } 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; } err = its_force_quiescent(its_base); if (err) { pr_warn("%s: failed to quiesce, giving up\n", node->full_name); 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); if ((tmp ^ baser) & GITS_CBASER_SHAREABILITY_MASK) { if (!(tmp & GITS_CBASER_SHAREABILITY_MASK)) { /* * The HW reports non-shareable, we must * remove the cacheability attributes as * well. */ baser &= ~(GITS_CBASER_SHAREABILITY_MASK | GITS_CBASER_CACHEABILITY_MASK); baser |= GITS_CBASER_nC; writeq_relaxed(baser, its->base + GITS_CBASER); } pr_info("ITS: using cache flushing for cmd queue\n"); its->flags |= ITS_FLAGS_CMDQ_NEEDS_FLUSHING; } writeq_relaxed(0, its->base + GITS_CWRITER); writel_relaxed(GITS_CTLR_ENABLE, its->base + GITS_CTLR); if (of_property_read_bool(its->msi_chip.of_node, "msi-controller")) { its->domain = irq_domain_add_tree(node, &its_domain_ops, its); if (!its->domain) { err = -ENOMEM; goto out_free_tables; } its->domain->parent = parent; its->domain->bus_token = DOMAIN_BUS_NEXUS; its->msi_chip.domain = its_pci_msi_alloc_domain(node, 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 (!list_empty(&its_nodes)) { if (!gic_rdists_supports_plpis()) { pr_info("CPU%d: LPIs not supported\n", smp_processor_id()); return -ENXIO; } 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; }