/* * I/O SAPIC support. * * Copyright (C) 1999 Intel Corp. * Copyright (C) 1999 Asit Mallick * Copyright (C) 2000-2002 J.I. Lee * Copyright (C) 1999-2000, 2002-2003 Hewlett-Packard Co. * David Mosberger-Tang * Copyright (C) 1999 VA Linux Systems * Copyright (C) 1999,2000 Walt Drummond * * 00/04/19 D. Mosberger Rewritten to mirror more closely the x86 I/O APIC code. * In particular, we now have separate handlers for edge * and level triggered interrupts. * 00/10/27 Asit Mallick, Goutham Rao IRQ vector allocation * PCI to vector mapping, shared PCI interrupts. * 00/10/27 D. Mosberger Document things a bit more to make them more understandable. * Clean up much of the old IOSAPIC cruft. * 01/07/27 J.I. Lee PCI irq routing, Platform/Legacy interrupts and fixes for * ACPI S5(SoftOff) support. * 02/01/23 J.I. Lee iosapic pgm fixes for PCI irq routing from _PRT * 02/01/07 E. Focht Redirectable interrupt vectors in * iosapic_set_affinity(), initializations for * /proc/irq/#/smp_affinity * 02/04/02 P. Diefenbaugh Cleaned up ACPI PCI IRQ routing. * 02/04/18 J.I. Lee bug fix in iosapic_init_pci_irq * 02/04/30 J.I. Lee bug fix in find_iosapic to fix ACPI PCI IRQ to IOSAPIC mapping * error * 02/07/29 T. Kochi Allocate interrupt vectors dynamically * 02/08/04 T. Kochi Cleaned up terminology (irq, global system interrupt, vector, etc.) * 02/09/20 D. Mosberger Simplified by taking advantage of ACPI's pci_irq code. * 03/02/19 B. Helgaas Make pcat_compat system-wide, not per-IOSAPIC. * Remove iosapic_address & gsi_base from external interfaces. * Rationalize __init/__devinit attributes. */ /* * Here is what the interrupt logic between a PCI device and the kernel looks like: * * (1) A PCI device raises one of the four interrupt pins (INTA, INTB, INTC, INTD). The * device is uniquely identified by its bus--, and slot-number (the function * number does not matter here because all functions share the same interrupt * lines). * * (2) The motherboard routes the interrupt line to a pin on a IOSAPIC controller. * Multiple interrupt lines may have to share the same IOSAPIC pin (if they're level * triggered and use the same polarity). Each interrupt line has a unique Global * System Interrupt (GSI) number which can be calculated as the sum of the controller's * base GSI number and the IOSAPIC pin number to which the line connects. * * (3) The IOSAPIC uses an internal routing table entries (RTEs) to map the IOSAPIC pin * into the IA-64 interrupt vector. This interrupt vector is then sent to the CPU. * * (4) The kernel recognizes an interrupt as an IRQ. The IRQ interface is used as * architecture-independent interrupt handling mechanism in Linux. As an * IRQ is a number, we have to have IA-64 interrupt vector number <-> IRQ number * mapping. On smaller systems, we use one-to-one mapping between IA-64 vector and * IRQ. A platform can implement platform_irq_to_vector(irq) and * platform_local_vector_to_irq(vector) APIs to differentiate the mapping. * Please see also include/asm-ia64/hw_irq.h for those APIs. * * To sum up, there are three levels of mappings involved: * * PCI pin -> global system interrupt (GSI) -> IA-64 vector <-> IRQ * * Note: The term "IRQ" is loosely used everywhere in Linux kernel to describe interrupts. * Now we use "IRQ" only for Linux IRQ's. ISA IRQ (isa_irq) is the only exception in this * source code. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #undef DEBUG_INTERRUPT_ROUTING #undef OVERRIDE_DEBUG #ifdef DEBUG_INTERRUPT_ROUTING #define DBG(fmt...) printk(fmt) #else #define DBG(fmt...) #endif static spinlock_t iosapic_lock = SPIN_LOCK_UNLOCKED; /* These tables map IA-64 vectors to the IOSAPIC pin that generates this vector. */ static struct iosapic_intr_info { char *addr; /* base address of IOSAPIC */ u32 low32; /* current value of low word of Redirection table entry */ unsigned int gsi_base; /* first GSI assigned to this IOSAPIC */ char rte_index; /* IOSAPIC RTE index (-1 => not an IOSAPIC interrupt) */ unsigned char dmode : 3; /* delivery mode (see iosapic.h) */ unsigned char polarity: 1; /* interrupt polarity (see iosapic.h) */ unsigned char trigger : 1; /* trigger mode (see iosapic.h) */ } iosapic_intr_info[IA64_NUM_VECTORS]; static struct iosapic { char *addr; /* base address of IOSAPIC */ unsigned int gsi_base; /* first GSI assigned to this IOSAPIC */ unsigned short num_rte; /* number of RTE in this IOSAPIC */ } iosapic_lists[NR_IOSAPICS]; static int num_iosapic; static unsigned char pcat_compat __initdata; /* 8259 compatibility flag */ /* * Find an IOSAPIC associated with a GSI */ static inline int find_iosapic (unsigned int gsi) { int i; for (i = 0; i < num_iosapic; i++) { if ((unsigned) (gsi - iosapic_lists[i].gsi_base) < iosapic_lists[i].num_rte) return i; } return -1; } static inline int _gsi_to_vector (unsigned int gsi) { struct iosapic_intr_info *info; for (info = iosapic_intr_info; info < iosapic_intr_info + IA64_NUM_VECTORS; ++info) if (info->gsi_base + info->rte_index == gsi) return info - iosapic_intr_info; return -1; } /* * Translate GSI number to the corresponding IA-64 interrupt vector. If no * entry exists, return -1. */ inline int gsi_to_vector (unsigned int gsi) { return _gsi_to_vector(gsi); } int gsi_to_irq (unsigned int gsi) { /* * XXX fix me: this assumes an identity mapping vetween IA-64 vector and Linux irq * numbers... */ return _gsi_to_vector(gsi); } static void set_rte (unsigned int vector, unsigned int dest, int mask) { unsigned long pol, trigger, dmode, flags; u32 low32, high32; char *addr; int rte_index; char redir; DBG(KERN_DEBUG"IOSAPIC: routing vector %d to 0x%x\n", vector, dest); rte_index = iosapic_intr_info[vector].rte_index; if (rte_index < 0) return; /* not an IOSAPIC interrupt */ addr = iosapic_intr_info[vector].addr; pol = iosapic_intr_info[vector].polarity; trigger = iosapic_intr_info[vector].trigger; dmode = iosapic_intr_info[vector].dmode; redir = (dmode == IOSAPIC_LOWEST_PRIORITY) ? 1 : 0; #ifdef CONFIG_SMP { unsigned int irq; for (irq = 0; irq < NR_IRQS; ++irq) if (irq_to_vector(irq) == vector) { set_irq_affinity_info(irq, (int)(dest & 0xffff), redir); break; } } #endif low32 = ((pol << IOSAPIC_POLARITY_SHIFT) | (trigger << IOSAPIC_TRIGGER_SHIFT) | (dmode << IOSAPIC_DELIVERY_SHIFT) | ((mask ? 1 : 0) << IOSAPIC_MASK_SHIFT) | vector); /* dest contains both id and eid */ high32 = (dest << IOSAPIC_DEST_SHIFT); spin_lock_irqsave(&iosapic_lock, flags); { writel(IOSAPIC_RTE_HIGH(rte_index), addr + IOSAPIC_REG_SELECT); writel(high32, addr + IOSAPIC_WINDOW); writel(IOSAPIC_RTE_LOW(rte_index), addr + IOSAPIC_REG_SELECT); writel(low32, addr + IOSAPIC_WINDOW); iosapic_intr_info[vector].low32 = low32; } spin_unlock_irqrestore(&iosapic_lock, flags); } static void nop (unsigned int vector) { /* do nothing... */ } static void mask_irq (unsigned int irq) { unsigned long flags; char *addr; u32 low32; int rte_index; ia64_vector vec = irq_to_vector(irq); addr = iosapic_intr_info[vec].addr; rte_index = iosapic_intr_info[vec].rte_index; if (rte_index < 0) return; /* not an IOSAPIC interrupt! */ spin_lock_irqsave(&iosapic_lock, flags); { writel(IOSAPIC_RTE_LOW(rte_index), addr + IOSAPIC_REG_SELECT); /* set only the mask bit */ low32 = iosapic_intr_info[vec].low32 |= IOSAPIC_MASK; writel(low32, addr + IOSAPIC_WINDOW); } spin_unlock_irqrestore(&iosapic_lock, flags); } static void unmask_irq (unsigned int irq) { unsigned long flags; char *addr; u32 low32; int rte_index; ia64_vector vec = irq_to_vector(irq); addr = iosapic_intr_info[vec].addr; rte_index = iosapic_intr_info[vec].rte_index; if (rte_index < 0) return; /* not an IOSAPIC interrupt! */ spin_lock_irqsave(&iosapic_lock, flags); { writel(IOSAPIC_RTE_LOW(rte_index), addr + IOSAPIC_REG_SELECT); low32 = iosapic_intr_info[vec].low32 &= ~IOSAPIC_MASK; writel(low32, addr + IOSAPIC_WINDOW); } spin_unlock_irqrestore(&iosapic_lock, flags); } static void iosapic_set_affinity (unsigned int irq, cpumask_t mask) { #ifdef CONFIG_SMP unsigned long flags; u32 high32, low32; int dest, rte_index; char *addr; int redir = (irq & IA64_IRQ_REDIRECTED) ? 1 : 0; ia64_vector vec; irq &= (~IA64_IRQ_REDIRECTED); vec = irq_to_vector(irq); if (cpus_empty(mask)) return; dest = cpu_physical_id(first_cpu(mask)); rte_index = iosapic_intr_info[vec].rte_index; addr = iosapic_intr_info[vec].addr; if (rte_index < 0) return; /* not an IOSAPIC interrupt */ set_irq_affinity_info(irq, dest, redir); /* dest contains both id and eid */ high32 = dest << IOSAPIC_DEST_SHIFT; spin_lock_irqsave(&iosapic_lock, flags); { /* get current delivery mode by reading the low32 */ writel(IOSAPIC_RTE_LOW(rte_index), addr + IOSAPIC_REG_SELECT); low32 = iosapic_intr_info[vec].low32 & ~(7 << IOSAPIC_DELIVERY_SHIFT); if (redir) /* change delivery mode to lowest priority */ low32 |= (IOSAPIC_LOWEST_PRIORITY << IOSAPIC_DELIVERY_SHIFT); else /* change delivery mode to fixed */ low32 |= (IOSAPIC_FIXED << IOSAPIC_DELIVERY_SHIFT); iosapic_intr_info[vec].low32 = low32; writel(IOSAPIC_RTE_HIGH(rte_index), addr + IOSAPIC_REG_SELECT); writel(high32, addr + IOSAPIC_WINDOW); writel(IOSAPIC_RTE_LOW(rte_index), addr + IOSAPIC_REG_SELECT); writel(low32, addr + IOSAPIC_WINDOW); } spin_unlock_irqrestore(&iosapic_lock, flags); #endif } /* * Handlers for level-triggered interrupts. */ static unsigned int iosapic_startup_level_irq (unsigned int irq) { unmask_irq(irq); return 0; } static void iosapic_end_level_irq (unsigned int irq) { ia64_vector vec = irq_to_vector(irq); writel(vec, iosapic_intr_info[vec].addr + IOSAPIC_EOI); } #define iosapic_shutdown_level_irq mask_irq #define iosapic_enable_level_irq unmask_irq #define iosapic_disable_level_irq mask_irq #define iosapic_ack_level_irq nop struct hw_interrupt_type irq_type_iosapic_level = { .typename = "IO-SAPIC-level", .startup = iosapic_startup_level_irq, .shutdown = iosapic_shutdown_level_irq, .enable = iosapic_enable_level_irq, .disable = iosapic_disable_level_irq, .ack = iosapic_ack_level_irq, .end = iosapic_end_level_irq, .set_affinity = iosapic_set_affinity }; /* * Handlers for edge-triggered interrupts. */ static unsigned int iosapic_startup_edge_irq (unsigned int irq) { unmask_irq(irq); /* * IOSAPIC simply drops interrupts pended while the * corresponding pin was masked, so we can't know if an * interrupt is pending already. Let's hope not... */ return 0; } static void iosapic_ack_edge_irq (unsigned int irq) { irq_desc_t *idesc = irq_descp(irq); /* * Once we have recorded IRQ_PENDING already, we can mask the * interrupt for real. This prevents IRQ storms from unhandled * devices. */ if ((idesc->status & (IRQ_PENDING|IRQ_DISABLED)) == (IRQ_PENDING|IRQ_DISABLED)) mask_irq(irq); } #define iosapic_enable_edge_irq unmask_irq #define iosapic_disable_edge_irq nop #define iosapic_end_edge_irq nop struct hw_interrupt_type irq_type_iosapic_edge = { .typename = "IO-SAPIC-edge", .startup = iosapic_startup_edge_irq, .shutdown = iosapic_disable_edge_irq, .enable = iosapic_enable_edge_irq, .disable = iosapic_disable_edge_irq, .ack = iosapic_ack_edge_irq, .end = iosapic_end_edge_irq, .set_affinity = iosapic_set_affinity }; unsigned int iosapic_version (char *addr) { /* * IOSAPIC Version Register return 32 bit structure like: * { * unsigned int version : 8; * unsigned int reserved1 : 8; * unsigned int max_redir : 8; * unsigned int reserved2 : 8; * } */ writel(IOSAPIC_VERSION, addr + IOSAPIC_REG_SELECT); return readl(IOSAPIC_WINDOW + addr); } /* * if the given vector is already owned by other, * assign a new vector for the other and make the vector available */ static void __init iosapic_reassign_vector (int vector) { int new_vector; if (iosapic_intr_info[vector].rte_index >= 0 || iosapic_intr_info[vector].addr || iosapic_intr_info[vector].gsi_base || iosapic_intr_info[vector].dmode || iosapic_intr_info[vector].polarity || iosapic_intr_info[vector].trigger) { new_vector = assign_irq_vector(AUTO_ASSIGN); printk(KERN_INFO "Reassigning vector %d to %d\n", vector, new_vector); memcpy(&iosapic_intr_info[new_vector], &iosapic_intr_info[vector], sizeof(struct iosapic_intr_info)); memset(&iosapic_intr_info[vector], 0, sizeof(struct iosapic_intr_info)); iosapic_intr_info[vector].rte_index = -1; } } static void register_intr (unsigned int gsi, int vector, unsigned char delivery, unsigned long polarity, unsigned long trigger) { irq_desc_t *idesc; struct hw_interrupt_type *irq_type; int rte_index; int index; unsigned long gsi_base; char *iosapic_address; index = find_iosapic(gsi); if (index < 0) { printk(KERN_WARNING "%s: No IOSAPIC for GSI 0x%x\n", __FUNCTION__, gsi); return; } iosapic_address = iosapic_lists[index].addr; gsi_base = iosapic_lists[index].gsi_base; rte_index = gsi - gsi_base; iosapic_intr_info[vector].rte_index = rte_index; iosapic_intr_info[vector].polarity = polarity; iosapic_intr_info[vector].dmode = delivery; iosapic_intr_info[vector].addr = iosapic_address; iosapic_intr_info[vector].gsi_base = gsi_base; iosapic_intr_info[vector].trigger = trigger; if (trigger == IOSAPIC_EDGE) irq_type = &irq_type_iosapic_edge; else irq_type = &irq_type_iosapic_level; idesc = irq_descp(vector); if (idesc->handler != irq_type) { if (idesc->handler != &no_irq_type) printk(KERN_WARNING "%s: changing vector %d from %s to %s\n", __FUNCTION__, vector, idesc->handler->typename, irq_type->typename); idesc->handler = irq_type; } } /* * ACPI can describe IOSAPIC interrupts via static tables and namespace * methods. This provides an interface to register those interrupts and * program the IOSAPIC RTE. */ int iosapic_register_intr (unsigned int gsi, unsigned long polarity, unsigned long trigger) { int vector; unsigned int dest = (ia64_getreg(_IA64_REG_CR_LID) >> 16) & 0xffff; vector = gsi_to_vector(gsi); if (vector < 0) vector = assign_irq_vector(AUTO_ASSIGN); register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY, polarity, trigger); printk(KERN_INFO "GSI 0x%x(%s,%s) -> CPU 0x%04x vector %d\n", gsi, (polarity == IOSAPIC_POL_HIGH ? "high" : "low"), (trigger == IOSAPIC_EDGE ? "edge" : "level"), dest, vector); /* program the IOSAPIC routing table */ set_rte(vector, dest, 0); return vector; } /* * ACPI calls this when it finds an entry for a platform interrupt. * Note that the irq_base and IOSAPIC address must be set in iosapic_init(). */ int __init iosapic_register_platform_intr (u32 int_type, unsigned int gsi, int iosapic_vector, u16 eid, u16 id, unsigned long polarity, unsigned long trigger) { unsigned char delivery; int vector; unsigned int dest = ((id << 8) | eid) & 0xffff; switch (int_type) { case ACPI_INTERRUPT_PMI: vector = iosapic_vector; /* * since PMI vector is alloc'd by FW(ACPI) not by kernel, * we need to make sure the vector is available */ iosapic_reassign_vector(vector); delivery = IOSAPIC_PMI; break; case ACPI_INTERRUPT_INIT: vector = assign_irq_vector(AUTO_ASSIGN); delivery = IOSAPIC_INIT; break; case ACPI_INTERRUPT_CPEI: vector = IA64_CPE_VECTOR; delivery = IOSAPIC_LOWEST_PRIORITY; break; default: printk(KERN_ERR "iosapic_register_platform_irq(): invalid int type\n"); return -1; } register_intr(gsi, vector, delivery, polarity, trigger); printk(KERN_INFO "PLATFORM int 0x%x: GSI 0x%x(%s,%s) -> CPU 0x%04x vector %d\n", int_type, gsi, (polarity == IOSAPIC_POL_HIGH ? "high" : "low"), (trigger == IOSAPIC_EDGE ? "edge" : "level"), dest, vector); /* program the IOSAPIC routing table */ set_rte(vector, dest, 0); return vector; } /* * ACPI calls this when it finds an entry for a legacy ISA IRQ override. * Note that the gsi_base and IOSAPIC address must be set in iosapic_init(). */ void __init iosapic_override_isa_irq (unsigned int isa_irq, unsigned int gsi, unsigned long polarity, unsigned long trigger) { int vector; unsigned int dest = (ia64_getreg(_IA64_REG_CR_LID) >> 16) & 0xffff; vector = isa_irq_to_vector(isa_irq); register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY, polarity, trigger); DBG("ISA: IRQ %u -> GSI 0x%x (%s,%s) -> CPU 0x%04x vector %d\n", isa_irq, gsi, polarity == IOSAPIC_POL_HIGH ? "high" : "low", trigger == IOSAPIC_EDGE ? "edge" : "level", dest, vector); /* program the IOSAPIC routing table */ set_rte(vector, dest, 0); } void __init iosapic_system_init (int system_pcat_compat) { int vector; for (vector = 0; vector < IA64_NUM_VECTORS; ++vector) iosapic_intr_info[vector].rte_index = -1; /* mark as unused */ pcat_compat = system_pcat_compat; if (pcat_compat) { /* * Disable the compatibility mode interrupts (8259 style), needs IN/OUT support * enabled. */ printk(KERN_INFO "%s: Disabling PC-AT compatible 8259 interrupts\n", __FUNCTION__); outb(0xff, 0xA1); outb(0xff, 0x21); } } void __init iosapic_init (unsigned long phys_addr, unsigned int gsi_base) { int num_rte; unsigned int isa_irq, ver; char *addr; addr = ioremap(phys_addr, 0); ver = iosapic_version(addr); /* * The MAX_REDIR register holds the highest input pin * number (starting from 0). * We add 1 so that we can use it for number of pins (= RTEs) */ num_rte = ((ver >> 16) & 0xff) + 1; iosapic_lists[num_iosapic].addr = addr; iosapic_lists[num_iosapic].gsi_base = gsi_base; iosapic_lists[num_iosapic].num_rte = num_rte; num_iosapic++; if ((gsi_base == 0) && pcat_compat) { /* * Map the legacy ISA devices into the IOSAPIC data. Some of these may * get reprogrammed later on with data from the ACPI Interrupt Source * Override table. */ for (isa_irq = 0; isa_irq < 16; ++isa_irq) iosapic_override_isa_irq(isa_irq, isa_irq, IOSAPIC_POL_HIGH, IOSAPIC_EDGE); } } void iosapic_enable_intr (unsigned int vector) { unsigned int dest; irq_desc_t *desc; /* * In the case of a shared interrupt, do not re-route the vector, and * especially do not mask a running interrupt (startup will not get * called for a shared interrupt). */ desc = irq_descp(vector); if (desc->action) return; #ifdef CONFIG_SMP /* * For platforms that do not support interrupt redirect via the XTP interface, we * can round-robin the PCI device interrupts to the processors */ if (!(smp_int_redirect & SMP_IRQ_REDIRECTION)) { static int cpu_index = -1; do if (++cpu_index >= NR_CPUS) cpu_index = 0; while (!cpu_online(cpu_index)); dest = cpu_physical_id(cpu_index) & 0xffff; } else { /* * Direct the interrupt vector to the current cpu, platform redirection * will distribute them. */ dest = (ia64_getreg(_IA64_REG_CR_LID) >> 16) & 0xffff; } #else /* direct the interrupt vector to the running cpu id */ dest = (ia64_getreg(_IA64_REG_CR_LID) >> 16) & 0xffff; #endif set_rte(vector, dest, 1); printk(KERN_INFO "IOSAPIC: vector %d -> CPU 0x%04x, enabled\n", vector, dest); } #ifdef CONFIG_ACPI_PCI void __init iosapic_parse_prt (void) { struct acpi_prt_entry *entry; struct list_head *node; unsigned int gsi; int vector; char pci_id[16]; struct hw_interrupt_type *irq_type = &irq_type_iosapic_level; irq_desc_t *idesc; list_for_each(node, &acpi_prt.entries) { entry = list_entry(node, struct acpi_prt_entry, node); /* We're only interested in static (non-link) entries. */ if (entry->link.handle) continue; gsi = entry->link.index; vector = gsi_to_vector(gsi); if (vector < 0) { if (find_iosapic(gsi) < 0) continue; /* allocate a vector for this interrupt line */ if (pcat_compat && (gsi < 16)) vector = isa_irq_to_vector(gsi); else /* new GSI; allocate a vector for it */ vector = assign_irq_vector(AUTO_ASSIGN); register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY, IOSAPIC_POL_LOW, IOSAPIC_LEVEL); } entry->irq = vector; snprintf(pci_id, sizeof(pci_id), "%02x:%02x:%02x[%c]", entry->id.segment, entry->id.bus, entry->id.device, 'A' + entry->pin); /* * If vector was previously initialized to a different * handler, re-initialize. */ idesc = irq_descp(vector); if (idesc->handler != irq_type) register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY, IOSAPIC_POL_LOW, IOSAPIC_LEVEL); } } #endif /* CONFIG_ACPI */