/* * Copyright 2008-2011 IBM Corporation. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include <linux/cpu.h> #include <linux/init.h> #include <linux/interrupt.h> #include <linux/irq.h> #include <linux/kernel.h> #include <linux/msi.h> #include <linux/of.h> #include <linux/slab.h> #include <linux/smp.h> #include <linux/spinlock.h> #include <linux/types.h> #include <linux/of_address.h> #include <linux/of_irq.h> #include <asm/io.h> #include <asm/irq.h> #include <asm/xics.h> #include "wsp.h" #include "ics.h" /* WSP ICS */ struct wsp_ics { struct ics ics; struct device_node *dn; void __iomem *regs; spinlock_t lock; unsigned long *bitmap; u32 chip_id; u32 lsi_base; u32 lsi_count; u64 hwirq_start; u64 count; #ifdef CONFIG_SMP int *hwirq_cpu_map; #endif }; #define to_wsp_ics(ics) container_of(ics, struct wsp_ics, ics) #define INT_SRC_LAYER_BUID_REG(base) ((base) + 0x00) #define IODA_TBL_ADDR_REG(base) ((base) + 0x18) #define IODA_TBL_DATA_REG(base) ((base) + 0x20) #define XIVE_UPDATE_REG(base) ((base) + 0x28) #define ICS_INT_CAPS_REG(base) ((base) + 0x30) #define TBL_AUTO_INCREMENT ((1UL << 63) | (1UL << 15)) #define TBL_SELECT_XIST (1UL << 48) #define TBL_SELECT_XIVT (1UL << 49) #define IODA_IRQ(irq) ((irq) & (0x7FFULL)) /* HRM 5.1.3.4 */ #define XIST_REQUIRED 0x8 #define XIST_REJECTED 0x4 #define XIST_PRESENTED 0x2 #define XIST_PENDING 0x1 #define XIVE_SERVER_SHIFT 42 #define XIVE_SERVER_MASK 0xFFFFULL #define XIVE_PRIORITY_MASK 0xFFULL #define XIVE_PRIORITY_SHIFT 32 #define XIVE_WRITE_ENABLE (1ULL << 63) /* * The docs refer to a 6 bit field called ChipID, which consists of a * 3 bit NodeID and a 3 bit ChipID. On WSP the ChipID is always zero * so we ignore it, and every where we use "chip id" in this code we * mean the NodeID. */ #define WSP_ICS_CHIP_SHIFT 17 static struct wsp_ics *ics_list; static int num_ics; /* ICS Source controller accessors */ static u64 wsp_ics_get_xive(struct wsp_ics *ics, unsigned int irq) { unsigned long flags; u64 xive; spin_lock_irqsave(&ics->lock, flags); out_be64(IODA_TBL_ADDR_REG(ics->regs), TBL_SELECT_XIVT | IODA_IRQ(irq)); xive = in_be64(IODA_TBL_DATA_REG(ics->regs)); spin_unlock_irqrestore(&ics->lock, flags); return xive; } static void wsp_ics_set_xive(struct wsp_ics *ics, unsigned int irq, u64 xive) { xive &= ~XIVE_ADDR_MASK; xive |= (irq & XIVE_ADDR_MASK); xive |= XIVE_WRITE_ENABLE; out_be64(XIVE_UPDATE_REG(ics->regs), xive); } static u64 xive_set_server(u64 xive, unsigned int server) { u64 mask = ~(XIVE_SERVER_MASK << XIVE_SERVER_SHIFT); xive &= mask; xive |= (server & XIVE_SERVER_MASK) << XIVE_SERVER_SHIFT; return xive; } static u64 xive_set_priority(u64 xive, unsigned int priority) { u64 mask = ~(XIVE_PRIORITY_MASK << XIVE_PRIORITY_SHIFT); xive &= mask; xive |= (priority & XIVE_PRIORITY_MASK) << XIVE_PRIORITY_SHIFT; return xive; } #ifdef CONFIG_SMP /* Find logical CPUs within mask on a given chip and store result in ret */ void cpus_on_chip(int chip_id, cpumask_t *mask, cpumask_t *ret) { int cpu, chip; struct device_node *cpu_dn, *dn; const u32 *prop; cpumask_clear(ret); for_each_cpu(cpu, mask) { cpu_dn = of_get_cpu_node(cpu, NULL); if (!cpu_dn) continue; prop = of_get_property(cpu_dn, "at-node", NULL); if (!prop) { of_node_put(cpu_dn); continue; } dn = of_find_node_by_phandle(*prop); of_node_put(cpu_dn); chip = wsp_get_chip_id(dn); if (chip == chip_id) cpumask_set_cpu(cpu, ret); of_node_put(dn); } } /* Store a suitable CPU to handle a hwirq in the ics->hwirq_cpu_map cache */ static int cache_hwirq_map(struct wsp_ics *ics, unsigned int hwirq, const cpumask_t *affinity) { cpumask_var_t avail, newmask; int ret = -ENOMEM, cpu, cpu_rover = 0, target; int index = hwirq - ics->hwirq_start; unsigned int nodeid; BUG_ON(index < 0 || index >= ics->count); if (!ics->hwirq_cpu_map) return -ENOMEM; if (!distribute_irqs) { ics->hwirq_cpu_map[hwirq - ics->hwirq_start] = xics_default_server; return 0; } /* Allocate needed CPU masks */ if (!alloc_cpumask_var(&avail, GFP_KERNEL)) goto ret; if (!alloc_cpumask_var(&newmask, GFP_KERNEL)) goto freeavail; /* Find PBus attached to the source of this IRQ */ nodeid = (hwirq >> WSP_ICS_CHIP_SHIFT) & 0x3; /* 12:14 */ /* Find CPUs that could handle this IRQ */ if (affinity) cpumask_and(avail, cpu_online_mask, affinity); else cpumask_copy(avail, cpu_online_mask); /* Narrow selection down to logical CPUs on the same chip */ cpus_on_chip(nodeid, avail, newmask); /* Ensure we haven't narrowed it down to 0 */ if (unlikely(cpumask_empty(newmask))) { if (unlikely(cpumask_empty(avail))) { ret = -1; goto out; } cpumask_copy(newmask, avail); } /* Choose a CPU out of those we narrowed it down to in round robin */ target = hwirq % cpumask_weight(newmask); for_each_cpu(cpu, newmask) { if (cpu_rover++ >= target) { ics->hwirq_cpu_map[index] = get_hard_smp_processor_id(cpu); ret = 0; goto out; } } /* Shouldn't happen */ WARN_ON(1); out: free_cpumask_var(newmask); freeavail: free_cpumask_var(avail); ret: if (ret < 0) { ics->hwirq_cpu_map[index] = cpumask_first(cpu_online_mask); pr_warning("Error, falling hwirq 0x%x routing back to CPU %i\n", hwirq, ics->hwirq_cpu_map[index]); } return ret; } static void alloc_irq_map(struct wsp_ics *ics) { int i; ics->hwirq_cpu_map = kmalloc(sizeof(int) * ics->count, GFP_KERNEL); if (!ics->hwirq_cpu_map) { pr_warning("Allocate hwirq_cpu_map failed, " "IRQ balancing disabled\n"); return; } for (i=0; i < ics->count; i++) ics->hwirq_cpu_map[i] = xics_default_server; } static int get_irq_server(struct wsp_ics *ics, unsigned int hwirq) { int index = hwirq - ics->hwirq_start; BUG_ON(index < 0 || index >= ics->count); if (!ics->hwirq_cpu_map) return xics_default_server; return ics->hwirq_cpu_map[index]; } #else /* !CONFIG_SMP */ static int cache_hwirq_map(struct wsp_ics *ics, unsigned int hwirq, const cpumask_t *affinity) { return 0; } static int get_irq_server(struct wsp_ics *ics, unsigned int hwirq) { return xics_default_server; } static void alloc_irq_map(struct wsp_ics *ics) { } #endif static void wsp_chip_unmask_irq(struct irq_data *d) { unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d); struct wsp_ics *ics; int server; u64 xive; if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS) return; ics = d->chip_data; if (WARN_ON(!ics)) return; server = get_irq_server(ics, hw_irq); xive = wsp_ics_get_xive(ics, hw_irq); xive = xive_set_server(xive, server); xive = xive_set_priority(xive, DEFAULT_PRIORITY); wsp_ics_set_xive(ics, hw_irq, xive); } static unsigned int wsp_chip_startup(struct irq_data *d) { /* unmask it */ wsp_chip_unmask_irq(d); return 0; } static void wsp_mask_real_irq(unsigned int hw_irq, struct wsp_ics *ics) { u64 xive; if (hw_irq == XICS_IPI) return; if (WARN_ON(!ics)) return; xive = wsp_ics_get_xive(ics, hw_irq); xive = xive_set_server(xive, xics_default_server); xive = xive_set_priority(xive, LOWEST_PRIORITY); wsp_ics_set_xive(ics, hw_irq, xive); } static void wsp_chip_mask_irq(struct irq_data *d) { unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d); struct wsp_ics *ics = d->chip_data; if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS) return; wsp_mask_real_irq(hw_irq, ics); } static int wsp_chip_set_affinity(struct irq_data *d, const struct cpumask *cpumask, bool force) { unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d); struct wsp_ics *ics; int ret; u64 xive; if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS) return -1; ics = d->chip_data; if (WARN_ON(!ics)) return -1; xive = wsp_ics_get_xive(ics, hw_irq); /* * For the moment only implement delivery to all cpus or one cpu. * Get current irq_server for the given irq */ ret = cache_hwirq_map(ics, hw_irq, cpumask); if (ret == -1) { char cpulist[128]; cpumask_scnprintf(cpulist, sizeof(cpulist), cpumask); pr_warning("%s: No online cpus in the mask %s for irq %d\n", __func__, cpulist, d->irq); return -1; } else if (ret == -ENOMEM) { pr_warning("%s: Out of memory\n", __func__); return -1; } xive = xive_set_server(xive, get_irq_server(ics, hw_irq)); wsp_ics_set_xive(ics, hw_irq, xive); return IRQ_SET_MASK_OK; } static struct irq_chip wsp_irq_chip = { .name = "WSP ICS", .irq_startup = wsp_chip_startup, .irq_mask = wsp_chip_mask_irq, .irq_unmask = wsp_chip_unmask_irq, .irq_set_affinity = wsp_chip_set_affinity }; static int wsp_ics_host_match(struct ics *ics, struct device_node *dn) { /* All ICSs in the system implement a global irq number space, * so match against them all. */ return of_device_is_compatible(dn, "ibm,ppc-xics"); } static int wsp_ics_match_hwirq(struct wsp_ics *wsp_ics, unsigned int hwirq) { if (hwirq >= wsp_ics->hwirq_start && hwirq < wsp_ics->hwirq_start + wsp_ics->count) return 1; return 0; } static int wsp_ics_map(struct ics *ics, unsigned int virq) { struct wsp_ics *wsp_ics = to_wsp_ics(ics); unsigned int hw_irq = virq_to_hw(virq); unsigned long flags; if (!wsp_ics_match_hwirq(wsp_ics, hw_irq)) return -ENOENT; irq_set_chip_and_handler(virq, &wsp_irq_chip, handle_fasteoi_irq); irq_set_chip_data(virq, wsp_ics); spin_lock_irqsave(&wsp_ics->lock, flags); bitmap_allocate_region(wsp_ics->bitmap, hw_irq - wsp_ics->hwirq_start, 0); spin_unlock_irqrestore(&wsp_ics->lock, flags); return 0; } static void wsp_ics_mask_unknown(struct ics *ics, unsigned long hw_irq) { struct wsp_ics *wsp_ics = to_wsp_ics(ics); if (!wsp_ics_match_hwirq(wsp_ics, hw_irq)) return; pr_err("%s: IRQ %lu (real) is invalid, disabling it.\n", __func__, hw_irq); wsp_mask_real_irq(hw_irq, wsp_ics); } static long wsp_ics_get_server(struct ics *ics, unsigned long hw_irq) { struct wsp_ics *wsp_ics = to_wsp_ics(ics); if (!wsp_ics_match_hwirq(wsp_ics, hw_irq)) return -ENOENT; return get_irq_server(wsp_ics, hw_irq); } /* HW Number allocation API */ static struct wsp_ics *wsp_ics_find_dn_ics(struct device_node *dn) { struct device_node *iparent; int i; iparent = of_irq_find_parent(dn); if (!iparent) { pr_err("wsp_ics: Failed to find interrupt parent!\n"); return NULL; } for(i = 0; i < num_ics; i++) { if(ics_list[i].dn == iparent) break; } if (i >= num_ics) { pr_err("wsp_ics: Unable to find parent bitmap!\n"); return NULL; } return &ics_list[i]; } int wsp_ics_alloc_irq(struct device_node *dn, int num) { struct wsp_ics *ics; int order, offset; ics = wsp_ics_find_dn_ics(dn); if (!ics) return -ENODEV; /* Fast, but overly strict if num isn't a power of two */ order = get_count_order(num); spin_lock_irq(&ics->lock); offset = bitmap_find_free_region(ics->bitmap, ics->count, order); spin_unlock_irq(&ics->lock); if (offset < 0) return offset; return offset + ics->hwirq_start; } void wsp_ics_free_irq(struct device_node *dn, unsigned int irq) { struct wsp_ics *ics; ics = wsp_ics_find_dn_ics(dn); if (WARN_ON(!ics)) return; spin_lock_irq(&ics->lock); bitmap_release_region(ics->bitmap, irq, 0); spin_unlock_irq(&ics->lock); } /* Initialisation */ static int __init wsp_ics_bitmap_setup(struct wsp_ics *ics, struct device_node *dn) { int len, i, j, size; u32 start, count; const u32 *p; size = BITS_TO_LONGS(ics->count) * sizeof(long); ics->bitmap = kzalloc(size, GFP_KERNEL); if (!ics->bitmap) { pr_err("wsp_ics: ENOMEM allocating IRQ bitmap!\n"); return -ENOMEM; } spin_lock_init(&ics->lock); p = of_get_property(dn, "available-ranges", &len); if (!p || !len) { /* FIXME this should be a WARN() once mambo is updated */ pr_err("wsp_ics: No available-ranges defined for %s\n", dn->full_name); return 0; } if (len % (2 * sizeof(u32)) != 0) { /* FIXME this should be a WARN() once mambo is updated */ pr_err("wsp_ics: Invalid available-ranges for %s\n", dn->full_name); return 0; } bitmap_fill(ics->bitmap, ics->count); for (i = 0; i < len / sizeof(u32); i += 2) { start = of_read_number(p + i, 1); count = of_read_number(p + i + 1, 1); pr_devel("%s: start: %d count: %d\n", __func__, start, count); if ((start + count) > (ics->hwirq_start + ics->count) || start < ics->hwirq_start) { pr_err("wsp_ics: Invalid range! -> %d to %d\n", start, start + count); break; } for (j = 0; j < count; j++) bitmap_release_region(ics->bitmap, (start + j) - ics->hwirq_start, 0); } /* Ensure LSIs are not available for allocation */ bitmap_allocate_region(ics->bitmap, ics->lsi_base, get_count_order(ics->lsi_count)); return 0; } static int __init wsp_ics_setup(struct wsp_ics *ics, struct device_node *dn) { u32 lsi_buid, msi_buid, msi_base, msi_count; void __iomem *regs; const u32 *p; int rc, len, i; u64 caps, buid; p = of_get_property(dn, "interrupt-ranges", &len); if (!p || len < (2 * sizeof(u32))) { pr_err("wsp_ics: No/bad interrupt-ranges found on %s\n", dn->full_name); return -ENOENT; } if (len > (2 * sizeof(u32))) { pr_err("wsp_ics: Multiple ics ranges not supported.\n"); return -EINVAL; } regs = of_iomap(dn, 0); if (!regs) { pr_err("wsp_ics: of_iomap(%s) failed\n", dn->full_name); return -ENXIO; } ics->hwirq_start = of_read_number(p, 1); ics->count = of_read_number(p + 1, 1); ics->regs = regs; ics->chip_id = wsp_get_chip_id(dn); if (WARN_ON(ics->chip_id < 0)) ics->chip_id = 0; /* Get some informations about the critter */ caps = in_be64(ICS_INT_CAPS_REG(ics->regs)); buid = in_be64(INT_SRC_LAYER_BUID_REG(ics->regs)); ics->lsi_count = caps >> 56; msi_count = (caps >> 44) & 0x7ff; /* Note: LSI BUID is 9 bits, but really only 3 are BUID and the * rest is mixed in the interrupt number. We store the whole * thing though */ lsi_buid = (buid >> 48) & 0x1ff; ics->lsi_base = (ics->chip_id << WSP_ICS_CHIP_SHIFT) | lsi_buid << 5; msi_buid = (buid >> 37) & 0x7; msi_base = (ics->chip_id << WSP_ICS_CHIP_SHIFT) | msi_buid << 11; pr_info("wsp_ics: Found %s\n", dn->full_name); pr_info("wsp_ics: irq range : 0x%06llx..0x%06llx\n", ics->hwirq_start, ics->hwirq_start + ics->count - 1); pr_info("wsp_ics: %4d LSIs : 0x%06x..0x%06x\n", ics->lsi_count, ics->lsi_base, ics->lsi_base + ics->lsi_count - 1); pr_info("wsp_ics: %4d MSIs : 0x%06x..0x%06x\n", msi_count, msi_base, msi_base + msi_count - 1); /* Let's check the HW config is sane */ if (ics->lsi_base < ics->hwirq_start || (ics->lsi_base + ics->lsi_count) > (ics->hwirq_start + ics->count)) pr_warning("wsp_ics: WARNING ! LSIs out of interrupt-ranges !\n"); if (msi_base < ics->hwirq_start || (msi_base + msi_count) > (ics->hwirq_start + ics->count)) pr_warning("wsp_ics: WARNING ! MSIs out of interrupt-ranges !\n"); /* We don't check for overlap between LSI and MSI, which will happen * if we use the same BUID, I'm not sure yet how legit that is. */ rc = wsp_ics_bitmap_setup(ics, dn); if (rc) { iounmap(regs); return rc; } ics->dn = of_node_get(dn); alloc_irq_map(ics); for(i = 0; i < ics->count; i++) wsp_mask_real_irq(ics->hwirq_start + i, ics); ics->ics.map = wsp_ics_map; ics->ics.mask_unknown = wsp_ics_mask_unknown; ics->ics.get_server = wsp_ics_get_server; ics->ics.host_match = wsp_ics_host_match; xics_register_ics(&ics->ics); return 0; } static void __init wsp_ics_set_default_server(void) { struct device_node *np; u32 hwid; /* Find the server number for the boot cpu. */ np = of_get_cpu_node(boot_cpuid, NULL); BUG_ON(!np); hwid = get_hard_smp_processor_id(boot_cpuid); pr_info("wsp_ics: default server is %#x, CPU %s\n", hwid, np->full_name); xics_default_server = hwid; of_node_put(np); } static int __init wsp_ics_init(void) { struct device_node *dn; struct wsp_ics *ics; int rc, found; wsp_ics_set_default_server(); found = 0; for_each_compatible_node(dn, NULL, "ibm,ppc-xics") found++; if (found == 0) { pr_err("wsp_ics: No ICS's found!\n"); return -ENODEV; } ics_list = kmalloc(sizeof(*ics) * found, GFP_KERNEL); if (!ics_list) { pr_err("wsp_ics: No memory for structs.\n"); return -ENOMEM; } num_ics = 0; ics = ics_list; for_each_compatible_node(dn, NULL, "ibm,wsp-xics") { rc = wsp_ics_setup(ics, dn); if (rc == 0) { ics++; num_ics++; } } if (found != num_ics) { pr_err("wsp_ics: Failed setting up %d ICS's\n", found - num_ics); return -1; } return 0; } void __init wsp_init_irq(void) { wsp_ics_init(); xics_init(); /* We need to patch our irq chip's EOI to point to the right ICP */ wsp_irq_chip.irq_eoi = icp_ops->eoi; } #ifdef CONFIG_PCI_MSI static void wsp_ics_msi_unmask_irq(struct irq_data *d) { wsp_chip_unmask_irq(d); unmask_msi_irq(d); } static unsigned int wsp_ics_msi_startup(struct irq_data *d) { wsp_ics_msi_unmask_irq(d); return 0; } static void wsp_ics_msi_mask_irq(struct irq_data *d) { mask_msi_irq(d); wsp_chip_mask_irq(d); } /* * we do it this way because we reassinge default EOI handling in * irq_init() above */ static void wsp_ics_eoi(struct irq_data *data) { wsp_irq_chip.irq_eoi(data); } static struct irq_chip wsp_ics_msi = { .name = "WSP ICS MSI", .irq_startup = wsp_ics_msi_startup, .irq_mask = wsp_ics_msi_mask_irq, .irq_unmask = wsp_ics_msi_unmask_irq, .irq_eoi = wsp_ics_eoi, .irq_set_affinity = wsp_chip_set_affinity }; void wsp_ics_set_msi_chip(unsigned int irq) { irq_set_chip(irq, &wsp_ics_msi); } void wsp_ics_set_std_chip(unsigned int irq) { irq_set_chip(irq, &wsp_irq_chip); } #endif /* CONFIG_PCI_MSI */