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Diffstat (limited to 'drivers/parisc/iosapic.c')
| -rw-r--r-- | drivers/parisc/iosapic.c | 921 |
1 files changed, 921 insertions, 0 deletions
diff --git a/drivers/parisc/iosapic.c b/drivers/parisc/iosapic.c new file mode 100644 index 00000000000..91df0bf181d --- /dev/null +++ b/drivers/parisc/iosapic.c @@ -0,0 +1,921 @@ +/* +** I/O Sapic Driver - PCI interrupt line support +** +** (c) Copyright 1999 Grant Grundler +** (c) Copyright 1999 Hewlett-Packard Company +** +** 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. +** +** The I/O sapic driver manages the Interrupt Redirection Table which is +** the control logic to convert PCI line based interrupts into a Message +** Signaled Interrupt (aka Transaction Based Interrupt, TBI). +** +** Acronyms +** -------- +** HPA Hard Physical Address (aka MMIO address) +** IRQ Interrupt ReQuest. Implies Line based interrupt. +** IRT Interrupt Routing Table (provided by PAT firmware) +** IRdT Interrupt Redirection Table. IRQ line to TXN ADDR/DATA +** table which is implemented in I/O SAPIC. +** ISR Interrupt Service Routine. aka Interrupt handler. +** MSI Message Signaled Interrupt. PCI 2.2 functionality. +** aka Transaction Based Interrupt (or TBI). +** PA Precision Architecture. HP's RISC architecture. +** RISC Reduced Instruction Set Computer. +** +** +** What's a Message Signalled Interrupt? +** ------------------------------------- +** MSI is a write transaction which targets a processor and is similar +** to a processor write to memory or MMIO. MSIs can be generated by I/O +** devices as well as processors and require *architecture* to work. +** +** PA only supports MSI. So I/O subsystems must either natively generate +** MSIs (e.g. GSC or HP-PB) or convert line based interrupts into MSIs +** (e.g. PCI and EISA). IA64 supports MSIs via a "local SAPIC" which +** acts on behalf of a processor. +** +** MSI allows any I/O device to interrupt any processor. This makes +** load balancing of the interrupt processing possible on an SMP platform. +** Interrupts are also ordered WRT to DMA data. It's possible on I/O +** coherent systems to completely eliminate PIO reads from the interrupt +** path. The device and driver must be designed and implemented to +** guarantee all DMA has been issued (issues about atomicity here) +** before the MSI is issued. I/O status can then safely be read from +** DMA'd data by the ISR. +** +** +** PA Firmware +** ----------- +** PA-RISC platforms have two fundementally different types of firmware. +** For PCI devices, "Legacy" PDC initializes the "INTERRUPT_LINE" register +** and BARs similar to a traditional PC BIOS. +** The newer "PAT" firmware supports PDC calls which return tables. +** PAT firmware only initializes PCI Console and Boot interface. +** With these tables, the OS can progam all other PCI devices. +** +** One such PAT PDC call returns the "Interrupt Routing Table" (IRT). +** The IRT maps each PCI slot's INTA-D "output" line to an I/O SAPIC +** input line. If the IRT is not available, this driver assumes +** INTERRUPT_LINE register has been programmed by firmware. The latter +** case also means online addition of PCI cards can NOT be supported +** even if HW support is present. +** +** All platforms with PAT firmware to date (Oct 1999) use one Interrupt +** Routing Table for the entire platform. +** +** Where's the iosapic? +** -------------------- +** I/O sapic is part of the "Core Electronics Complex". And on HP platforms +** it's integrated as part of the PCI bus adapter, "lba". So no bus walk +** will discover I/O Sapic. I/O Sapic driver learns about each device +** when lba driver advertises the presence of the I/O sapic by calling +** iosapic_register(). +** +** +** IRQ handling notes +** ------------------ +** The IO-SAPIC can indicate to the CPU which interrupt was asserted. +** So, unlike the GSC-ASIC and Dino, we allocate one CPU interrupt per +** IO-SAPIC interrupt and call the device driver's handler directly. +** The IO-SAPIC driver hijacks the CPU interrupt handler so it can +** issue the End Of Interrupt command to the IO-SAPIC. +** +** Overview of exported iosapic functions +** -------------------------------------- +** (caveat: code isn't finished yet - this is just the plan) +** +** iosapic_init: +** o initialize globals (lock, etc) +** o try to read IRT. Presence of IRT determines if this is +** a PAT platform or not. +** +** iosapic_register(): +** o create iosapic_info instance data structure +** o allocate vector_info array for this iosapic +** o initialize vector_info - read corresponding IRdT? +** +** iosapic_xlate_pin: (only called by fixup_irq for PAT platform) +** o intr_pin = read cfg (INTERRUPT_PIN); +** o if (device under PCI-PCI bridge) +** translate slot/pin +** +** iosapic_fixup_irq: +** o if PAT platform (IRT present) +** intr_pin = iosapic_xlate_pin(isi,pcidev): +** intr_line = find IRT entry(isi, PCI_SLOT(pcidev), intr_pin) +** save IRT entry into vector_info later +** write cfg INTERRUPT_LINE (with intr_line)? +** else +** intr_line = pcidev->irq +** IRT pointer = NULL +** endif +** o locate vector_info (needs: isi, intr_line) +** o allocate processor "irq" and get txn_addr/data +** o request_irq(processor_irq, iosapic_interrupt, vector_info,...) +** +** iosapic_enable_irq: +** o clear any pending IRQ on that line +** o enable IRdT - call enable_irq(vector[line]->processor_irq) +** o write EOI in case line is already asserted. +** +** iosapic_disable_irq: +** o disable IRdT - call disable_irq(vector[line]->processor_irq) +*/ + + +/* FIXME: determine which include files are really needed */ +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/spinlock.h> +#include <linux/pci.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/interrupt.h> + +#include <asm/byteorder.h> /* get in-line asm for swab */ +#include <asm/pdc.h> +#include <asm/pdcpat.h> +#include <asm/page.h> +#include <asm/system.h> +#include <asm/io.h> /* read/write functions */ +#ifdef CONFIG_SUPERIO +#include <asm/superio.h> +#endif + +#include <asm/iosapic.h> +#include "./iosapic_private.h" + +#define MODULE_NAME "iosapic" + +/* "local" compile flags */ +#undef PCI_BRIDGE_FUNCS +#undef DEBUG_IOSAPIC +#undef DEBUG_IOSAPIC_IRT + + +#ifdef DEBUG_IOSAPIC +#define DBG(x...) printk(x) +#else /* DEBUG_IOSAPIC */ +#define DBG(x...) +#endif /* DEBUG_IOSAPIC */ + +#ifdef DEBUG_IOSAPIC_IRT +#define DBG_IRT(x...) printk(x) +#else +#define DBG_IRT(x...) +#endif + +#ifdef CONFIG_64BIT +#define COMPARE_IRTE_ADDR(irte, hpa) ((irte)->dest_iosapic_addr == (hpa)) +#else +#define COMPARE_IRTE_ADDR(irte, hpa) \ + ((irte)->dest_iosapic_addr == ((hpa) | 0xffffffff00000000ULL)) +#endif + +#define IOSAPIC_REG_SELECT 0x00 +#define IOSAPIC_REG_WINDOW 0x10 +#define IOSAPIC_REG_EOI 0x40 + +#define IOSAPIC_REG_VERSION 0x1 + +#define IOSAPIC_IRDT_ENTRY(idx) (0x10+(idx)*2) +#define IOSAPIC_IRDT_ENTRY_HI(idx) (0x11+(idx)*2) + +static inline unsigned int iosapic_read(void __iomem *iosapic, unsigned int reg) +{ + writel(reg, iosapic + IOSAPIC_REG_SELECT); + return readl(iosapic + IOSAPIC_REG_WINDOW); +} + +static inline void iosapic_write(void __iomem *iosapic, unsigned int reg, u32 val) +{ + writel(reg, iosapic + IOSAPIC_REG_SELECT); + writel(val, iosapic + IOSAPIC_REG_WINDOW); +} + +#define IOSAPIC_VERSION_MASK 0x000000ff +#define IOSAPIC_VERSION(ver) ((int) (ver & IOSAPIC_VERSION_MASK)) + +#define IOSAPIC_MAX_ENTRY_MASK 0x00ff0000 +#define IOSAPIC_MAX_ENTRY_SHIFT 0x10 +#define IOSAPIC_IRDT_MAX_ENTRY(ver) \ + (int) (((ver) & IOSAPIC_MAX_ENTRY_MASK) >> IOSAPIC_MAX_ENTRY_SHIFT) + +/* bits in the "low" I/O Sapic IRdT entry */ +#define IOSAPIC_IRDT_ENABLE 0x10000 +#define IOSAPIC_IRDT_PO_LOW 0x02000 +#define IOSAPIC_IRDT_LEVEL_TRIG 0x08000 +#define IOSAPIC_IRDT_MODE_LPRI 0x00100 + +/* bits in the "high" I/O Sapic IRdT entry */ +#define IOSAPIC_IRDT_ID_EID_SHIFT 0x10 + + +static spinlock_t iosapic_lock = SPIN_LOCK_UNLOCKED; + +static inline void iosapic_eoi(void __iomem *addr, unsigned int data) +{ + __raw_writel(data, addr); +} + +/* +** REVISIT: future platforms may have more than one IRT. +** If so, the following three fields form a structure which +** then be linked into a list. Names are chosen to make searching +** for them easy - not necessarily accurate (eg "cell"). +** +** Alternative: iosapic_info could point to the IRT it's in. +** iosapic_register() could search a list of IRT's. +*/ +static struct irt_entry *irt_cell; +static size_t irt_num_entry; + +static struct irt_entry *iosapic_alloc_irt(int num_entries) +{ + unsigned long a; + + /* The IRT needs to be 8-byte aligned for the PDC call. + * Normally kmalloc would guarantee larger alignment, but + * if CONFIG_DEBUG_SLAB is enabled, then we can get only + * 4-byte alignment on 32-bit kernels + */ + a = (unsigned long)kmalloc(sizeof(struct irt_entry) * num_entries + 8, GFP_KERNEL); + a = (a + 7) & ~7; + return (struct irt_entry *)a; +} + +/** + * iosapic_load_irt - Fill in the interrupt routing table + * @cell_num: The cell number of the CPU we're currently executing on + * @irt: The address to place the new IRT at + * @return The number of entries found + * + * The "Get PCI INT Routing Table Size" option returns the number of + * entries in the PCI interrupt routing table for the cell specified + * in the cell_number argument. The cell number must be for a cell + * within the caller's protection domain. + * + * The "Get PCI INT Routing Table" option returns, for the cell + * specified in the cell_number argument, the PCI interrupt routing + * table in the caller allocated memory pointed to by mem_addr. + * We assume the IRT only contains entries for I/O SAPIC and + * calculate the size based on the size of I/O sapic entries. + * + * The PCI interrupt routing table entry format is derived from the + * IA64 SAL Specification 2.4. The PCI interrupt routing table defines + * the routing of PCI interrupt signals between the PCI device output + * "pins" and the IO SAPICs' input "lines" (including core I/O PCI + * devices). This table does NOT include information for devices/slots + * behind PCI to PCI bridges. See PCI to PCI Bridge Architecture Spec. + * for the architected method of routing of IRQ's behind PPB's. + */ + + +static int __init +iosapic_load_irt(unsigned long cell_num, struct irt_entry **irt) +{ + long status; /* PDC return value status */ + struct irt_entry *table; /* start of interrupt routing tbl */ + unsigned long num_entries = 0UL; + + BUG_ON(!irt); + + if (is_pdc_pat()) { + /* Use pat pdc routine to get interrupt routing table size */ + DBG("calling get_irt_size (cell %ld)\n", cell_num); + status = pdc_pat_get_irt_size(&num_entries, cell_num); + DBG("get_irt_size: %ld\n", status); + + BUG_ON(status != PDC_OK); + BUG_ON(num_entries == 0); + + /* + ** allocate memory for interrupt routing table + ** This interface isn't really right. We are assuming + ** the contents of the table are exclusively + ** for I/O sapic devices. + */ + table = iosapic_alloc_irt(num_entries); + if (table == NULL) { + printk(KERN_WARNING MODULE_NAME ": read_irt : can " + "not alloc mem for IRT\n"); + return 0; + } + + /* get PCI INT routing table */ + status = pdc_pat_get_irt(table, cell_num); + DBG("pdc_pat_get_irt: %ld\n", status); + WARN_ON(status != PDC_OK); + } else { + /* + ** C3000/J5000 (and similar) platforms with Sprockets PDC + ** will return exactly one IRT for all iosapics. + ** So if we have one, don't need to get it again. + */ + if (irt_cell) + return 0; + + /* Should be using the Elroy's HPA, but it's ignored anyway */ + status = pdc_pci_irt_size(&num_entries, 0); + DBG("pdc_pci_irt_size: %ld\n", status); + + if (status != PDC_OK) { + /* Not a "legacy" system with I/O SAPIC either */ + return 0; + } + + BUG_ON(num_entries == 0); + + table = iosapic_alloc_irt(num_entries); + if (!table) { + printk(KERN_WARNING MODULE_NAME ": read_irt : can " + "not alloc mem for IRT\n"); + return 0; + } + + /* HPA ignored by this call too. */ + status = pdc_pci_irt(num_entries, 0, table); + BUG_ON(status != PDC_OK); + } + + /* return interrupt table address */ + *irt = table; + +#ifdef DEBUG_IOSAPIC_IRT +{ + struct irt_entry *p = table; + int i; + + printk(MODULE_NAME " Interrupt Routing Table (cell %ld)\n", cell_num); + printk(MODULE_NAME " start = 0x%p num_entries %ld entry_size %d\n", + table, + num_entries, + (int) sizeof(struct irt_entry)); + + for (i = 0 ; i < num_entries ; i++, p++) { + printk(MODULE_NAME " %02x %02x %02x %02x %02x %02x %02x %02x %08x%08x\n", + p->entry_type, p->entry_length, p->interrupt_type, + p->polarity_trigger, p->src_bus_irq_devno, p->src_bus_id, + p->src_seg_id, p->dest_iosapic_intin, + ((u32 *) p)[2], + ((u32 *) p)[3] + ); + } +} +#endif /* DEBUG_IOSAPIC_IRT */ + + return num_entries; +} + + + +void __init iosapic_init(void) +{ + unsigned long cell = 0; + + DBG("iosapic_init()\n"); + +#ifdef __LP64__ + if (is_pdc_pat()) { + int status; + struct pdc_pat_cell_num cell_info; + + status = pdc_pat_cell_get_number(&cell_info); + if (status == PDC_OK) { + cell = cell_info.cell_num; + } + } +#endif + + /* get interrupt routing table for this cell */ + irt_num_entry = iosapic_load_irt(cell, &irt_cell); + if (irt_num_entry == 0) + irt_cell = NULL; /* old PDC w/o iosapic */ +} + + +/* +** Return the IRT entry in case we need to look something else up. +*/ +static struct irt_entry * +irt_find_irqline(struct iosapic_info *isi, u8 slot, u8 intr_pin) +{ + struct irt_entry *i = irt_cell; + int cnt; /* track how many entries we've looked at */ + u8 irq_devno = (slot << IRT_DEV_SHIFT) | (intr_pin-1); + + DBG_IRT("irt_find_irqline() SLOT %d pin %d\n", slot, intr_pin); + + for (cnt=0; cnt < irt_num_entry; cnt++, i++) { + + /* + ** Validate: entry_type, entry_length, interrupt_type + ** + ** Difference between validate vs compare is the former + ** should print debug info and is not expected to "fail" + ** on current platforms. + */ + if (i->entry_type != IRT_IOSAPIC_TYPE) { + DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry %d type %d\n", i, cnt, i->entry_type); + continue; + } + + if (i->entry_length != IRT_IOSAPIC_LENGTH) { + DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry %d length %d\n", i, cnt, i->entry_length); + continue; + } + + if (i->interrupt_type != IRT_VECTORED_INTR) { + DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry %d interrupt_type %d\n", i, cnt, i->interrupt_type); + continue; + } + + if (!COMPARE_IRTE_ADDR(i, isi->isi_hpa)) + continue; + + if ((i->src_bus_irq_devno & IRT_IRQ_DEVNO_MASK) != irq_devno) + continue; + + /* + ** Ignore: src_bus_id and rc_seg_id correlate with + ** iosapic_info->isi_hpa on HP platforms. + ** If needed, pass in "PFA" (aka config space addr) + ** instead of slot. + */ + + /* Found it! */ + return i; + } + + printk(KERN_WARNING MODULE_NAME ": 0x%lx : no IRT entry for slot %d, pin %d\n", + isi->isi_hpa, slot, intr_pin); + return NULL; +} + + +/* +** xlate_pin() supports the skewing of IRQ lines done by subsidiary bridges. +** Legacy PDC already does this translation for us and stores it in INTR_LINE. +** +** PAT PDC needs to basically do what legacy PDC does: +** o read PIN +** o adjust PIN in case device is "behind" a PPB +** (eg 4-port 100BT and SCSI/LAN "Combo Card") +** o convert slot/pin to I/O SAPIC input line. +** +** HP platforms only support: +** o one level of skewing for any number of PPBs +** o only support PCI-PCI Bridges. +*/ +static struct irt_entry * +iosapic_xlate_pin(struct iosapic_info *isi, struct pci_dev *pcidev) +{ + u8 intr_pin, intr_slot; + + pci_read_config_byte(pcidev, PCI_INTERRUPT_PIN, &intr_pin); + + DBG_IRT("iosapic_xlate_pin(%s) SLOT %d pin %d\n", + pcidev->slot_name, PCI_SLOT(pcidev->devfn), intr_pin); + + if (intr_pin == 0) { + /* The device does NOT support/use IRQ lines. */ + return NULL; + } + + /* Check if pcidev behind a PPB */ + if (NULL != pcidev->bus->self) { + /* Convert pcidev INTR_PIN into something we + ** can lookup in the IRT. + */ +#ifdef PCI_BRIDGE_FUNCS + /* + ** Proposal #1: + ** + ** call implementation specific translation function + ** This is architecturally "cleaner". HP-UX doesn't + ** support other secondary bus types (eg. E/ISA) directly. + ** May be needed for other processor (eg IA64) architectures + ** or by some ambitous soul who wants to watch TV. + */ + if (pci_bridge_funcs->xlate_intr_line) { + intr_pin = pci_bridge_funcs->xlate_intr_line(pcidev); + } +#else /* PCI_BRIDGE_FUNCS */ + struct pci_bus *p = pcidev->bus; + /* + ** Proposal #2: + ** The "pin" is skewed ((pin + dev - 1) % 4). + ** + ** This isn't very clean since I/O SAPIC must assume: + ** - all platforms only have PCI busses. + ** - only PCI-PCI bridge (eg not PCI-EISA, PCI-PCMCIA) + ** - IRQ routing is only skewed once regardless of + ** the number of PPB's between iosapic and device. + ** (Bit3 expansion chassis follows this rule) + ** + ** Advantage is it's really easy to implement. + */ + intr_pin = ((intr_pin-1)+PCI_SLOT(pcidev->devfn)) % 4; + intr_pin++; /* convert back to INTA-D (1-4) */ +#endif /* PCI_BRIDGE_FUNCS */ + + /* + ** Locate the host slot the PPB nearest the Host bus + ** adapter. + */ + while (NULL != p->parent->self) + p = p->parent; + + intr_slot = PCI_SLOT(p->self->devfn); + } else { + intr_slot = PCI_SLOT(pcidev->devfn); + } + DBG_IRT("iosapic_xlate_pin: bus %d slot %d pin %d\n", + pcidev->bus->secondary, intr_slot, intr_pin); + + return irt_find_irqline(isi, intr_slot, intr_pin); +} + +static void iosapic_rd_irt_entry(struct vector_info *vi , u32 *dp0, u32 *dp1) +{ + struct iosapic_info *isp = vi->iosapic; + u8 idx = vi->irqline; + + *dp0 = iosapic_read(isp->addr, IOSAPIC_IRDT_ENTRY(idx)); + *dp1 = iosapic_read(isp->addr, IOSAPIC_IRDT_ENTRY_HI(idx)); +} + + +static void iosapic_wr_irt_entry(struct vector_info *vi, u32 dp0, u32 dp1) +{ + struct iosapic_info *isp = vi->iosapic; + + DBG_IRT("iosapic_wr_irt_entry(): irq %d hpa %lx 0x%x 0x%x\n", + vi->irqline, isp->isi_hpa, dp0, dp1); + + iosapic_write(isp->addr, IOSAPIC_IRDT_ENTRY(vi->irqline), dp0); + + /* Read the window register to flush the writes down to HW */ + dp0 = readl(isp->addr+IOSAPIC_REG_WINDOW); + + iosapic_write(isp->addr, IOSAPIC_IRDT_ENTRY_HI(vi->irqline), dp1); + + /* Read the window register to flush the writes down to HW */ + dp1 = readl(isp->addr+IOSAPIC_REG_WINDOW); +} + +/* +** set_irt prepares the data (dp0, dp1) according to the vector_info +** and target cpu (id_eid). dp0/dp1 are then used to program I/O SAPIC +** IRdT for the given "vector" (aka IRQ line). +*/ +static void +iosapic_set_irt_data( struct vector_info *vi, u32 *dp0, u32 *dp1) +{ + u32 mode = 0; + struct irt_entry *p = vi->irte; + + if ((p->polarity_trigger & IRT_PO_MASK) == IRT_ACTIVE_LO) + mode |= IOSAPIC_IRDT_PO_LOW; + + if (((p->polarity_trigger >> IRT_EL_SHIFT) & IRT_EL_MASK) == IRT_LEVEL_TRIG) + mode |= IOSAPIC_IRDT_LEVEL_TRIG; + + /* + ** IA64 REVISIT + ** PA doesn't support EXTINT or LPRIO bits. + */ + + *dp0 = mode | (u32) vi->txn_data; + + /* + ** Extracting id_eid isn't a real clean way of getting it. + ** But the encoding is the same for both PA and IA64 platforms. + */ + if (is_pdc_pat()) { + /* + ** PAT PDC just hands it to us "right". + ** txn_addr comes from cpu_data[x].txn_addr. + */ + *dp1 = (u32) (vi->txn_addr); + } else { + /* + ** eg if base_addr == 0xfffa0000), + ** we want to get 0xa0ff0000. + ** + ** eid 0x0ff00000 -> 0x00ff0000 + ** id 0x000ff000 -> 0xff000000 + */ + *dp1 = (((u32)vi->txn_addr & 0x0ff00000) >> 4) | + (((u32)vi->txn_addr & 0x000ff000) << 12); + } + DBG_IRT("iosapic_set_irt_data(): 0x%x 0x%x\n", *dp0, *dp1); +} + + +static struct vector_info *iosapic_get_vector(unsigned int irq) +{ + return irq_desc[irq].handler_data; +} + +static void iosapic_disable_irq(unsigned int irq) +{ + unsigned long flags; + struct vector_info *vi = iosapic_get_vector(irq); + u32 d0, d1; + + spin_lock_irqsave(&iosapic_lock, flags); + iosapic_rd_irt_entry(vi, &d0, &d1); + d0 |= IOSAPIC_IRDT_ENABLE; + iosapic_wr_irt_entry(vi, d0, d1); + spin_unlock_irqrestore(&iosapic_lock, flags); +} + +static void iosapic_enable_irq(unsigned int irq) +{ + struct vector_info *vi = iosapic_get_vector(irq); + u32 d0, d1; + + /* data is initialized by fixup_irq */ + WARN_ON(vi->txn_irq == 0); + + iosapic_set_irt_data(vi, &d0, &d1); + iosapic_wr_irt_entry(vi, d0, d1); + +#ifdef DEBUG_IOSAPIC_IRT +{ + u32 *t = (u32 *) ((ulong) vi->eoi_addr & ~0xffUL); + printk("iosapic_enable_irq(): regs %p", vi->eoi_addr); + for ( ; t < vi->eoi_addr; t++) + printk(" %x", readl(t)); + printk("\n"); +} + +printk("iosapic_enable_irq(): sel "); +{ + struct iosapic_info *isp = vi->iosapic; + + for (d0=0x10; d0<0x1e; d0++) { + d1 = iosapic_read(isp->addr, d0); + printk(" %x", d1); + } +} +printk("\n"); +#endif + + /* + * Issuing I/O SAPIC an EOI causes an interrupt IFF IRQ line is + * asserted. IRQ generally should not be asserted when a driver + * enables their IRQ. It can lead to "interesting" race conditions + * in the driver initialization sequence. + */ + DBG(KERN_DEBUG "enable_irq(%d): eoi(%p, 0x%x)\n", irq, + vi->eoi_addr, vi->eoi_data); + iosapic_eoi(vi->eoi_addr, vi->eoi_data); +} + +/* + * PARISC only supports PCI devices below I/O SAPIC. + * PCI only supports level triggered in order to share IRQ lines. + * ergo I/O SAPIC must always issue EOI on parisc. + * + * i386/ia64 support ISA devices and have to deal with + * edge-triggered interrupts too. + */ +static void iosapic_end_irq(unsigned int irq) +{ + struct vector_info *vi = iosapic_get_vector(irq); + DBG(KERN_DEBUG "end_irq(%d): eoi(%p, 0x%x)\n", irq, + vi->eoi_addr, vi->eoi_data); + iosapic_eoi(vi->eoi_addr, vi->eoi_data); +} + +static unsigned int iosapic_startup_irq(unsigned int irq) +{ + iosapic_enable_irq(irq); + return 0; +} + +static struct hw_interrupt_type iosapic_interrupt_type = { + .typename = "IO-SAPIC-level", + .startup = iosapic_startup_irq, + .shutdown = iosapic_disable_irq, + .enable = iosapic_enable_irq, + .disable = iosapic_disable_irq, + .ack = no_ack_irq, + .end = iosapic_end_irq, +// .set_affinity = iosapic_set_affinity_irq, +}; + +int iosapic_fixup_irq(void *isi_obj, struct pci_dev *pcidev) +{ + struct iosapic_info *isi = isi_obj; + struct irt_entry *irte = NULL; /* only used if PAT PDC */ + struct vector_info *vi; + int isi_line; /* line used by device */ + + if (!isi) { + printk(KERN_WARNING MODULE_NAME ": hpa not registered for %s\n", + pci_name(pcidev)); + return -1; + } + +#ifdef CONFIG_SUPERIO + /* + * HACK ALERT! (non-compliant PCI device support) + * + * All SuckyIO interrupts are routed through the PIC's on function 1. + * But SuckyIO OHCI USB controller gets an IRT entry anyway because + * it advertises INT D for INT_PIN. Use that IRT entry to get the + * SuckyIO interrupt routing for PICs on function 1 (*BLEECCHH*). + */ + if (is_superio_device(pcidev)) { + /* We must call superio_fixup_irq() to register the pdev */ + pcidev->irq = superio_fixup_irq(pcidev); + + /* Don't return if need to program the IOSAPIC's IRT... */ + if (PCI_FUNC(pcidev->devfn) != SUPERIO_USB_FN) + return pcidev->irq; + } +#endif /* CONFIG_SUPERIO */ + + /* lookup IRT entry for isi/slot/pin set */ + irte = iosapic_xlate_pin(isi, pcidev); + if (!irte) { + printk("iosapic: no IRTE for %s (IRQ not connected?)\n", + pci_name(pcidev)); + return -1; + } + DBG_IRT("iosapic_fixup_irq(): irte %p %x %x %x %x %x %x %x %x\n", + irte, + irte->entry_type, + irte->entry_length, + irte->polarity_trigger, + irte->src_bus_irq_devno, + irte->src_bus_id, + irte->src_seg_id, + irte->dest_iosapic_intin, + (u32) irte->dest_iosapic_addr); + isi_line = irte->dest_iosapic_intin; + + /* get vector info for this input line */ + vi = isi->isi_vector + isi_line; + DBG_IRT("iosapic_fixup_irq: line %d vi 0x%p\n", isi_line, vi); + + /* If this IRQ line has already been setup, skip it */ + if (vi->irte) + goto out; + + vi->irte = irte; + + /* + * Allocate processor IRQ + * + * XXX/FIXME The txn_alloc_irq() code and related code should be + * moved to enable_irq(). That way we only allocate processor IRQ + * bits for devices that actually have drivers claiming them. + * Right now we assign an IRQ to every PCI device present, + * regardless of whether it's used or not. + */ + vi->txn_irq = txn_alloc_irq(8); + + if (vi->txn_irq < 0) + panic("I/O sapic: couldn't get TXN IRQ\n"); + + /* enable_irq() will use txn_* to program IRdT */ + vi->txn_addr = txn_alloc_addr(vi->txn_irq); + vi->txn_data = txn_alloc_data(vi->txn_irq); + + vi->eoi_addr = isi->addr + IOSAPIC_REG_EOI; + vi->eoi_data = cpu_to_le32(vi->txn_data); + + cpu_claim_irq(vi->txn_irq, &iosapic_interrupt_type, vi); + + out: + pcidev->irq = vi->txn_irq; + + DBG_IRT("iosapic_fixup_irq() %d:%d %x %x line %d irq %d\n", + PCI_SLOT(pcidev->devfn), PCI_FUNC(pcidev->devfn), + pcidev->vendor, pcidev->device, isi_line, pcidev->irq); + + return pcidev->irq; +} + + +/* +** squirrel away the I/O Sapic Version +*/ +static unsigned int +iosapic_rd_version(struct iosapic_info *isi) +{ + return iosapic_read(isi->addr, IOSAPIC_REG_VERSION); +} + + +/* +** iosapic_register() is called by "drivers" with an integrated I/O SAPIC. +** Caller must be certain they have an I/O SAPIC and know its MMIO address. +** +** o allocate iosapic_info and add it to the list +** o read iosapic version and squirrel that away +** o read size of IRdT. +** o allocate and initialize isi_vector[] +** o allocate irq region +*/ +void *iosapic_register(unsigned long hpa) +{ + struct iosapic_info *isi = NULL; + struct irt_entry *irte = irt_cell; + struct vector_info *vip; + int cnt; /* track how many entries we've looked at */ + + /* + * Astro based platforms can only support PCI OLARD if they implement + * PAT PDC. Legacy PDC omits LBAs with no PCI devices from the IRT. + * Search the IRT and ignore iosapic's which aren't in the IRT. + */ + for (cnt=0; cnt < irt_num_entry; cnt++, irte++) { + WARN_ON(IRT_IOSAPIC_TYPE != irte->entry_type); + if (COMPARE_IRTE_ADDR(irte, hpa)) + break; + } + + if (cnt >= irt_num_entry) { + DBG("iosapic_register() ignoring 0x%lx (NOT FOUND)\n", hpa); + return NULL; + } + + isi = (struct iosapic_info *)kmalloc(sizeof(struct iosapic_info), GFP_KERNEL); + if (!isi) { + BUG(); + return NULL; + } + + memset(isi, 0, sizeof(struct iosapic_info)); + + isi->addr = ioremap(hpa, 4096); + isi->isi_hpa = hpa; + isi->isi_version = iosapic_rd_version(isi); + isi->isi_num_vectors = IOSAPIC_IRDT_MAX_ENTRY(isi->isi_version) + 1; + + vip = isi->isi_vector = (struct vector_info *) + kmalloc(sizeof(struct vector_info) * isi->isi_num_vectors, GFP_KERNEL); + if (vip == NULL) { + kfree(isi); + return NULL; + } + + memset(vip, 0, sizeof(struct vector_info) * isi->isi_num_vectors); + + for (cnt=0; cnt < isi->isi_num_vectors; cnt++, vip++) { + vip->irqline = (unsigned char) cnt; + vip->iosapic = isi; + } + return isi; +} + + +#ifdef DEBUG_IOSAPIC + +static void +iosapic_prt_irt(void *irt, long num_entry) +{ + unsigned int i, *irp = (unsigned int *) irt; + + + printk(KERN_DEBUG MODULE_NAME ": Interrupt Routing Table (%lx entries)\n", num_entry); + + for (i=0; i<num_entry; i++, irp += 4) { + printk(KERN_DEBUG "%p : %2d %.8x %.8x %.8x %.8x\n", + irp, i, irp[0], irp[1], irp[2], irp[3]); + } +} + + +static void +iosapic_prt_vi(struct vector_info *vi) +{ + printk(KERN_DEBUG MODULE_NAME ": vector_info[%d] is at %p\n", vi->irqline, vi); + printk(KERN_DEBUG "\t\tstatus: %.4x\n", vi->status); + printk(KERN_DEBUG "\t\ttxn_irq: %d\n", vi->txn_irq); + printk(KERN_DEBUG "\t\ttxn_addr: %lx\n", vi->txn_addr); + printk(KERN_DEBUG "\t\ttxn_data: %lx\n", vi->txn_data); + printk(KERN_DEBUG "\t\teoi_addr: %p\n", vi->eoi_addr); + printk(KERN_DEBUG "\t\teoi_data: %x\n", vi->eoi_data); +} + + +static void +iosapic_prt_isi(struct iosapic_info *isi) +{ + printk(KERN_DEBUG MODULE_NAME ": io_sapic_info at %p\n", isi); + printk(KERN_DEBUG "\t\tisi_hpa: %lx\n", isi->isi_hpa); + printk(KERN_DEBUG "\t\tisi_status: %x\n", isi->isi_status); + printk(KERN_DEBUG "\t\tisi_version: %x\n", isi->isi_version); + printk(KERN_DEBUG "\t\tisi_vector: %p\n", isi->isi_vector); +} +#endif /* DEBUG_IOSAPIC */ |