/* -*- mode: c; c-basic-offset: 8 -*- */
/* Copyright (C) 1999,2001
*
* Author: J.E.J.Bottomley@HansenPartnership.com
*
* linux/arch/i386/kernel/voyager_smp.c
*
* This file provides all the same external entries as smp.c but uses
* the voyager hal to provide the functionality
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/kernel_stat.h>
#include <linux/delay.h>
#include <linux/mc146818rtc.h>
#include <linux/cache.h>
#include <linux/interrupt.h>
#include <linux/smp_lock.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/bootmem.h>
#include <linux/completion.h>
#include <asm/desc.h>
#include <asm/voyager.h>
#include <asm/vic.h>
#include <asm/mtrr.h>
#include <asm/pgalloc.h>
#include <asm/tlbflush.h>
#include <asm/arch_hooks.h>
/* TLB state -- visible externally, indexed physically */
DEFINE_PER_CPU(struct tlb_state, cpu_tlbstate) ____cacheline_aligned = { &init_mm, 0 };
/* CPU IRQ affinity -- set to all ones initially */
static unsigned long cpu_irq_affinity[NR_CPUS] __cacheline_aligned = { [0 ... NR_CPUS-1] = ~0UL };
/* per CPU data structure (for /proc/cpuinfo et al), visible externally
* indexed physically */
struct cpuinfo_x86 cpu_data[NR_CPUS] __cacheline_aligned;
EXPORT_SYMBOL(cpu_data);
/* physical ID of the CPU used to boot the system */
unsigned char boot_cpu_id;
/* The memory line addresses for the Quad CPIs */
struct voyager_qic_cpi *voyager_quad_cpi_addr[NR_CPUS] __cacheline_aligned;
/* The masks for the Extended VIC processors, filled in by cat_init */
__u32 voyager_extended_vic_processors = 0;
/* Masks for the extended Quad processors which cannot be VIC booted */
__u32 voyager_allowed_boot_processors = 0;
/* The mask for the Quad Processors (both extended and non-extended) */
__u32 voyager_quad_processors = 0;
/* Total count of live CPUs, used in process.c to display
* the CPU information and in irq.c for the per CPU irq
* activity count. Finally exported by i386_ksyms.c */
static int voyager_extended_cpus = 1;
/* Have we found an SMP box - used by time.c to do the profiling
interrupt for timeslicing; do not set to 1 until the per CPU timer
interrupt is active */
int smp_found_config = 0;
/* Used for the invalidate map that's also checked in the spinlock */
static volatile unsigned long smp_invalidate_needed;
/* Bitmask of currently online CPUs - used by setup.c for
/proc/cpuinfo, visible externally but still physical */
cpumask_t cpu_online_map = CPU_MASK_NONE;
EXPORT_SYMBOL(cpu_online_map);
/* Bitmask of CPUs present in the system - exported by i386_syms.c, used
* by scheduler but indexed physically */
cpumask_t phys_cpu_present_map = CPU_MASK_NONE;
/* The internal functions */
static void send_CPI(__u32 cpuset, __u8 cpi);
static void ack_CPI(__u8 cpi);
static int ack_QIC_CPI(__u8 cpi);
static void ack_special_QIC_CPI(__u8 cpi);
static void ack_VIC_CPI(__u8 cpi);
static void send_CPI_allbutself(__u8 cpi);
static void enable_vic_irq(unsigned int irq);
static void disable_vic_irq(unsigned int irq);
static unsigned int startup_vic_irq(unsigned int irq);
static void enable_local_vic_irq(unsigned int irq);
static void disable_local_vic_irq(unsigned int irq);
static void before_handle_vic_irq(unsigned int irq);
static void after_handle_vic_irq(unsigned int irq);
static void set_vic_irq_affinity(unsigned int irq, cpumask_t mask);
static void ack_vic_irq(unsigned int irq);
static void vic_enable_cpi(void);
static void do_boot_cpu(__u8 cpuid);
static void do_quad_bootstrap(void);
int hard_smp_processor_id(void);
/* Inline functions */
static inline void
send_one_QIC_CPI(__u8 cpu, __u8 cpi)
{
voyager_quad_cpi_addr[cpu]->qic_cpi[cpi].cpi =
(smp_processor_id() << 16) + cpi;
}
static inline void
send_QIC_CPI(__u32 cpuset, __u8 cpi)
{
int cpu;
for_each_online_cpu(cpu) {
if(cpuset & (1<<cpu)) {
#ifdef VOYAGER_DEBUG
if(!cpu_isset(cpu, cpu_online_map))
VDEBUG(("CPU%d sending cpi %d to CPU%d not in cpu_online_map\n", hard_smp_processor_id(), cpi, cpu));
#endif
send_one_QIC_CPI(cpu, cpi - QIC_CPI_OFFSET);
}
}
}
static inline void
wrapper_smp_local_timer_interrupt(struct pt_regs *regs)
{
irq_enter();
smp_local_timer_interrupt(regs);
irq_exit();
}
static inline void
send_one_CPI(__u8 cpu, __u8 cpi)
{
if(voyager_quad_processors & (1<<cpu))
send_one_QIC_CPI(cpu, cpi - QIC_CPI_OFFSET);
else
send_CPI(1<<cpu, cpi);
}
static inline void
send_CPI_allbutself(__u8 cpi)
{
__u8 cpu = smp_processor_id();
__u32 mask = cpus_addr(cpu_online_map)[0] & ~(1 << cpu);
send_CPI(mask, cpi);
}
static inline int
is_cpu_quad(void)
{
__u8 cpumask = inb(VIC_PROC_WHO_AM_I);
return ((cpumask & QUAD_IDENTIFIER) == QUAD_IDENTIFIER);
}
static inline int
is_cpu_extended(void)
{
__u8 cpu = hard_smp_processor_id();
return(voyager_extended_vic_processors & (1<<cpu));
}
static inline int
is_cpu_vic_boot(void)
{
__u8 cpu = hard_smp_processor_id();
return(voyager_extended_vic_processors
& voyager_allowed_boot_processors & (1<<cpu));
}
static inline void
ack_CPI(__u8 cpi)
{
switch(cpi) {
case VIC_CPU_BOOT_CPI:
if(is_cpu_quad() && !is_cpu_vic_boot())
ack_QIC_CPI(cpi);
else
ack_VIC_CPI(cpi);
break;
case VIC_SYS_INT:
case VIC_CMN_INT:
/* These are slightly strange. Even on the Quad card,
* They are vectored as VIC CPIs */
if(is_cpu_quad())
ack_special_QIC_CPI(cpi);
else
ack_VIC_CPI(cpi);
break;
default:
printk("VOYAGER ERROR: CPI%d is in common CPI code\n", cpi);
break;
}
}
/* local variables */
/* The VIC IRQ descriptors -- these look almost identical to the
* 8259 IRQs except that masks and things must be kept per processor
*/
static struct hw_interrupt_type vic_irq_type = {
.typename = "VIC-level",
.startup = startup_vic_irq,
.shutdown = disable_vic_irq,
.enable = enable_vic_irq,
.disable = disable_vic_irq,
.ack = before_handle_vic_irq,
.end = after_handle_vic_irq,
.set_affinity = set_vic_irq_affinity,
};
/* used to count up as CPUs are brought on line (starts at 0) */
static int cpucount = 0;
/* steal a page from the bottom of memory for the trampoline and
* squirrel its address away here. This will be in kernel virtual
* space */
static __u32 trampoline_base;
/* The per cpu profile stuff - used in smp_local_timer_interrupt */
static DEFINE_PER_CPU(int, prof_multiplier) = 1;
static DEFINE_PER_CPU(int, prof_old_multiplier) = 1;
static DEFINE_PER_CPU(int, prof_counter) = 1;
/* the map used to check if a CPU has booted */
static __u32 cpu_booted_map;
/* the synchronize flag used to hold all secondary CPUs spinning in
* a tight loop until the boot sequence is ready for them */
static cpumask_t smp_commenced_mask = CPU_MASK_NONE;
/* This is for the new dynamic CPU boot code */
cpumask_t cpu_callin_map = CPU_MASK_NONE;
cpumask_t cpu_callout_map = CPU_MASK_NONE;
EXPORT_SYMBOL(cpu_callout_map);
cpumask_t cpu_possible_map = CPU_MASK_NONE;
EXPORT_SYMBOL(cpu_possible_map);
/* The per processor IRQ masks (these are usually kept in sync) */
static __u16 vic_irq_mask[NR_CPUS] __cacheline_aligned;
/* the list of IRQs to be enabled by the VIC_ENABLE_IRQ_CPI */
static __u16 vic_irq_enable_mask[NR_CPUS] __cacheline_aligned = { 0 };
/* Lock for enable/disable of VIC interrupts */
static __cacheline_aligned DEFINE_SPINLOCK(vic_irq_lock);
/* The boot processor is correctly set up in PC mode when it
* comes up, but the secondaries need their master/slave 8259
* pairs initializing correctly */
/* Interrupt counters (per cpu) and total - used to try to
* even up the interrupt handling routines */
static long vic_intr_total = 0;
static long vic_intr_count[NR_CPUS] __cacheline_aligned = { 0 };
static unsigned long vic_tick[NR_CPUS] __cacheline_aligned = { 0 };
/* Since we can only use CPI0, we fake all the other CPIs */
static unsigned long vic_cpi_mailbox[NR_CPUS] __cacheline_aligned;
/* debugging routine to read the isr of the cpu's pic */
static inline __u16
vic_read_isr(void)
{
__u16 isr;
outb(0x0b, 0xa0);
isr = inb(0xa0) << 8;
outb(0x0b, 0x20);
isr |= inb(0x20);
return isr;
}
static __init void
qic_setup(void)
{
if(!is_cpu_quad()) {
/* not a quad, no setup */
return;
}
outb(QIC_DEFAULT_MASK0, QIC_MASK_REGISTER0);
outb(QIC_CPI_ENABLE, QIC_MASK_REGISTER1);
if(is_cpu_extended()) {
/* the QIC duplicate of the VIC base register */
outb(VIC_DEFAULT_CPI_BASE, QIC_VIC_CPI_BASE_REGISTER);
outb(QIC_DEFAULT_CPI_BASE, QIC_CPI_BASE_REGISTER);
/* FIXME: should set up the QIC timer and memory parity
* error vectors here */
}
}
static __init void
vic_setup_pic(void)
{
outb(1, VIC_REDIRECT_REGISTER_1);
/* clear the claim registers for dynamic routing */
outb(0, VIC_CLAIM_REGISTER_0);
outb(0, VIC_CLAIM_REGISTER_1);
outb(0, VIC_PRIORITY_REGISTER);
/* Set the Primary and Secondary Microchannel vector
* bases to be the same as the ordinary interrupts
*
* FIXME: This would be more efficient using separate
* vectors. */
outb(FIRST_EXTERNAL_VECTOR, VIC_PRIMARY_MC_BASE);
outb(FIRST_EXTERNAL_VECTOR, VIC_SECONDARY_MC_BASE);
/* Now initiallise the master PIC belonging to this CPU by
* sending the four ICWs */
/* ICW1: level triggered, ICW4 needed */
outb(0x19, 0x20);
/* ICW2: vector base */
outb(FIRST_EXTERNAL_VECTOR, 0x21);
/* ICW3: slave at line 2 */
outb(0x04, 0x21);
/* ICW4: 8086 mode */
outb(0x01, 0x21);
/* now the same for the slave PIC */
/* ICW1: level trigger, ICW4 needed */
outb(0x19, 0xA0);
/* ICW2: slave vector base */
outb(FIRST_EXTERNAL_VECTOR + 8, 0xA1);
/* ICW3: slave ID */
outb(0x02, 0xA1);
/* ICW4: 8086 mode */
outb(0x01, 0xA1);
}
static void
do_quad_bootstrap(void)
{
if(is_cpu_quad() && is_cpu_vic_boot()) {
int i;
unsigned long flags;
__u8 cpuid = hard_smp_processor_id();
local_irq_save(flags);
for(i = 0; i<4; i++) {
/* FIXME: this would be >>3 &0x7 on the 32 way */
if(((cpuid >> 2) & 0x03) == i)
/* don't lower our own mask! */
continue;
/* masquerade as local Quad CPU */
outb(QIC_CPUID_ENABLE | i, QIC_PROCESSOR_ID);
/* enable the startup CPI */
outb(QIC_BOOT_CPI_MASK, QIC_MASK_REGISTER1);
/* restore cpu id */
outb(0, QIC_PROCESSOR_ID);
}
local_irq_restore(flags);
}
}
/* Set up all the basic stuff: read the SMP config and make all the
* SMP information reflect only the boot cpu. All others will be
* brought on-line later. */
void __init
find_smp_config(void)
{
int i;
boot_cpu_id = hard_smp_processor_id();
printk("VOYAGER SMP: Boot cpu is %d\n", boot_cpu_id);
/* initialize the CPU structures (moved from smp_boot_cpus) */
for(i=0; i<NR_CPUS; i++) {
cpu_irq_affinity[i] = ~0;
}
cpu_online_map = cpumask_of_cpu(boot_cpu_id);
/* The boot CPU must be extended */
voyager_extended_vic_processors = 1<<boot_cpu_id;
/* initially, all of the first 8 cpu's can boot */
voyager_allowed_boot_processors = 0xff;
/* set up everything for just this CPU, we can alter
* this as we start the other CPUs later */
/* now get the CPU disposition from the extended CMOS */
cpus_addr(phys_cpu_present_map)[0] = voyager_extended_cmos_read(VOYAGER_PROCESSOR_PRESENT_MASK);
cpus_addr(phys_cpu_present_map)[0] |= voyager_extended_cmos_read(VOYAGER_PROCESSOR_PRESENT_MASK + 1) << 8;
cpus_addr(phys_cpu_present_map)[0] |= voyager_extended_cmos_read(VOYAGER_PROCESSOR_PRESENT_MASK + 2) << 16;
cpus_addr(phys_cpu_present_map)[0] |= voyager_extended_cmos_read(VOYAGER_PROCESSOR_PRESENT_MASK + 3) << 24;
cpu_possible_map = phys_cpu_present_map;
printk("VOYAGER SMP: phys_cpu_present_map = 0x%lx\n", cpus_addr(phys_cpu_present_map)[0]);
/* Here we set up the VIC to enable SMP */
/* enable the CPIs by writing the base vector to their register */
outb(VIC_DEFAULT_CPI_BASE, VIC_CPI_BASE_REGISTER);
outb(1, VIC_REDIRECT_REGISTER_1);
/* set the claim registers for static routing --- Boot CPU gets
* all interrupts untill all other CPUs started */
outb(0xff, VIC_CLAIM_REGISTER_0);
outb(0xff, VIC_CLAIM_REGISTER_1);
/* Set the Primary and Secondary Microchannel vector
* bases to be the same as the ordinary interrupts
*
* FIXME: This would be more efficient using separate
* vectors. */
outb(FIRST_EXTERNAL_VECTOR, VIC_PRIMARY_MC_BASE);
outb(FIRST_EXTERNAL_VECTOR, VIC_SECONDARY_MC_BASE);
/* Finally tell the firmware that we're driving */
outb(inb(VOYAGER_SUS_IN_CONTROL_PORT) | VOYAGER_IN_CONTROL_FLAG,
VOYAGER_SUS_IN_CONTROL_PORT);
current_thread_info()->cpu = boot_cpu_id;
}
/*
* The bootstrap kernel entry code has set these up. Save them
* for a given CPU, id is physical */
void __init
smp_store_cpu_info(int id)
{
struct cpuinfo_x86 *c=&cpu_data[id];
*c = boot_cpu_data;
identify_cpu(c);
}
/* set up the trampoline and return the physical address of the code */
static __u32 __init
setup_trampoline(void)
{
/* these two are global symbols in trampoline.S */
extern __u8 trampoline_end[];
extern __u8 trampoline_data[];
memcpy((__u8 *)trampoline_base, trampoline_data,
trampoline_end - trampoline_data);
return virt_to_phys((__u8 *)trampoline_base);
}
/* Routine initially called when a non-boot CPU is brought online */
static void __init
start_secondary(void *unused)
{
__u8 cpuid = hard_smp_processor_id();
/* external functions not defined in the headers */
extern void calibrate_delay(void);
cpu_init();
/* OK, we're in the routine */
ack_CPI(VIC_CPU_BOOT_CPI);
/* setup the 8259 master slave pair belonging to this CPU ---
* we won't actually receive any until the boot CPU
* relinquishes it's static routing mask */
vic_setup_pic();
qic_setup();
if(is_cpu_quad() && !is_cpu_vic_boot()) {
/* clear the boot CPI */
__u8 dummy;
dummy = voyager_quad_cpi_addr[cpuid]->qic_cpi[VIC_CPU_BOOT_CPI].cpi;
printk("read dummy %d\n", dummy);
}
/* lower the mask to receive CPIs */
vic_enable_cpi();
VDEBUG(("VOYAGER SMP: CPU%d, stack at about %p\n", cpuid, &cpuid));
/* enable interrupts */
local_irq_enable();
/* get our bogomips */
calibrate_delay();
/* save our processor parameters */
smp_store_cpu_info(cpuid);
/* if we're a quad, we may need to bootstrap other CPUs */
do_quad_bootstrap();
/* FIXME: this is rather a poor hack to prevent the CPU
* activating softirqs while it's supposed to be waiting for
* permission to proceed. Without this, the new per CPU stuff
* in the softirqs will fail */
local_irq_disable();
cpu_set(cpuid, cpu_callin_map);
/* signal that we're done */
cpu_booted_map = 1;
while (!cpu_isset(cpuid, smp_commenced_mask))
rep_nop();
local_irq_enable();
local_flush_tlb();
cpu_set(cpuid, cpu_online_map);
wmb();
cpu_idle();
}
/* Routine to kick start the given CPU and wait for it to report ready
* (or timeout in startup). When this routine returns, the requested
* CPU is either fully running and configured or known to be dead.
*
* We call this routine sequentially 1 CPU at a time, so no need for
* locking */
static void __init
do_boot_cpu(__u8 cpu)
{
struct task_struct *idle;
int timeout;
unsigned long flags;
int quad_boot = (1<<cpu) & voyager_quad_processors
& ~( voyager_extended_vic_processors
& voyager_allowed_boot_processors);
/* For the 486, we can't use the 4Mb page table trick, so
* must map a region of memory */
#ifdef CONFIG_M486
int i;
unsigned long *page_table_copies = (unsigned long *)
__get_free_page(GFP_KERNEL);
#endif
pgd_t orig_swapper_pg_dir0;
/* This is an area in head.S which was used to set up the
* initial kernel stack. We need to alter this to give the
* booting CPU a new stack (taken from its idle process) */
extern struct {
__u8 *esp;
unsigned short ss;
} stack_start;
/* This is the format of the CPI IDT gate (in real mode) which
* we're hijacking to boot the CPU */
union IDTFormat {
struct seg {
__u16 Offset;
__u16 Segment;
} idt;
__u32 val;
} hijack_source;
__u32 *hijack_vector;
__u32 start_phys_address = setup_trampoline();
/* There's a clever trick to this: The linux trampoline is
* compiled to begin at absolute location zero, so make the
* address zero but have the data segment selector compensate
* for the actual address */
hijack_source.idt.Offset = start_phys_address & 0x000F;
hijack_source.idt.Segment = (start_phys_address >> 4) & 0xFFFF;
cpucount++;
idle = fork_idle(cpu);
if(IS_ERR(idle))
panic("failed fork for CPU%d", cpu);
idle->thread.eip = (unsigned long) start_secondary;
/* init_tasks (in sched.c) is indexed logically */
stack_start.esp = (void *) idle->thread.esp;
irq_ctx_init(cpu);
/* Note: Don't modify initial ss override */
VDEBUG(("VOYAGER SMP: Booting CPU%d at 0x%lx[%x:%x], stack %p\n", cpu,
(unsigned long)hijack_source.val, hijack_source.idt.Segment,
hijack_source.idt.Offset, stack_start.esp));
/* set the original swapper_pg_dir[0] to map 0 to 4Mb transparently
* (so that the booting CPU can find start_32 */
orig_swapper_pg_dir0 = swapper_pg_dir[0];
#ifdef CONFIG_M486
if(page_table_copies == NULL)
panic("No free memory for 486 page tables\n");
for(i = 0; i < PAGE_SIZE/sizeof(unsigned long); i++)
page_table_copies[i] = (i * PAGE_SIZE)
| _PAGE_RW | _PAGE_USER | _PAGE_PRESENT;
((unsigned long *)swapper_pg_dir)[0] =
((virt_to_phys(page_table_copies)) & PAGE_MASK)
| _PAGE_RW | _PAGE_USER | _PAGE_PRESENT;
#else
((unsigned long *)swapper_pg_dir)[0] =
(virt_to_phys(pg0) & PAGE_MASK)
| _PAGE_RW | _PAGE_USER | _PAGE_PRESENT;
#endif
if(quad_boot) {
printk("CPU %d: non extended Quad boot\n", cpu);
hijack_vector = (__u32 *)phys_to_virt((VIC_CPU_BOOT_CPI + QIC_DEFAULT_CPI_BASE)*4);
*hijack_vector = hijack_source.val;
} else {
printk("CPU%d: extended VIC boot\n", cpu);
hijack_vector = (__u32 *)phys_to_virt((VIC_CPU_BOOT_CPI + VIC_DEFAULT_CPI_BASE)*4);
*hijack_vector = hijack_source.val;
/* VIC errata, may also receive interrupt at this address */
hijack_vector = (__u32 *)phys_to_virt((VIC_CPU_BOOT_ERRATA_CPI + VIC_DEFAULT_CPI_BASE)*4);
*hijack_vector = hijack_source.val;
}
/* All non-boot CPUs start with interrupts fully masked. Need
* to lower the mask of the CPI we're about to send. We do
* this in the VIC by masquerading as the processor we're
* about to boot and lowering its interrupt mask */
local_irq_save(flags);
if(quad_boot) {
send_one_QIC_CPI(cpu, VIC_CPU_BOOT_CPI);
} else {
outb(VIC_CPU_MASQUERADE_ENABLE | cpu, VIC_PROCESSOR_ID);
/* here we're altering registers belonging to `cpu' */
outb(VIC_BOOT_INTERRUPT_MASK, 0x21);
/* now go back to our original identity */
outb(boot_cpu_id, VIC_PROCESSOR_ID);
/* and boot the CPU */
send_CPI((1<<cpu), VIC_CPU_BOOT_CPI);
}
cpu_booted_map = 0;
local_irq_restore(flags);
/* now wait for it to become ready (or timeout) */
for(timeout = 0; timeout < 50000; timeout++) {
if(cpu_booted_map)
break;
udelay(100);
}
/* reset the page table */
swapper_pg_dir[0] = orig_swapper_pg_dir0;
local_flush_tlb();
#ifdef CONFIG_M486
free_page((unsigned long)page_table_copies);
#endif
if (cpu_booted_map) {
VDEBUG(("CPU%d: Booted successfully, back in CPU %d\n",
cpu, smp_processor_id()));
printk("CPU%d: ", cpu);
print_cpu_info(&cpu_data[cpu]);
wmb();
cpu_set(cpu, cpu_callout_map);
cpu_set(cpu, cpu_present_map);
}
else {
printk("CPU%d FAILED TO BOOT: ", cpu);
if (*((volatile unsigned char *)phys_to_virt(start_phys_address))==0xA5)
printk("Stuck.\n");
else
printk("Not responding.\n");
cpucount--;
}
}
void __init
smp_boot_cpus(void)
{
int i;
/* CAT BUS initialisation must be done after the memory */
/* FIXME: The L4 has a catbus too, it just needs to be
* accessed in a totally different way */
if(voyager_level == 5) {
voyager_cat_init();
/* now that the cat has probed the Voyager System Bus, sanity
* check the cpu map */
if( ((voyager_quad_processors | voyager_extended_vic_processors)
& cpus_addr(phys_cpu_present_map)[0]) != cpus_addr(phys_cpu_present_map)[0]) {
/* should panic */
printk("\n\n***WARNING*** Sanity check of CPU present map FAILED\n");
}
} else if(voyager_level == 4)
voyager_extended_vic_processors = cpus_addr(phys_cpu_present_map)[0];
/* this sets up the idle task to run on the current cpu */
voyager_extended_cpus = 1;
/* Remove the global_irq_holder setting, it triggers a BUG() on
* schedule at the moment */
//global_irq_holder = boot_cpu_id;
/* FIXME: Need to do something about this but currently only works
* on CPUs with a tsc which none of mine have.
smp_tune_scheduling();
*/
smp_store_cpu_info(boot_cpu_id);
printk("CPU%d: ", boot_cpu_id);
print_cpu_info(&cpu_data[boot_cpu_id]);
if(is_cpu_quad()) {
/* booting on a Quad CPU */
printk("VOYAGER SMP: Boot CPU is Quad\n");
qic_setup();
do_quad_bootstrap();
}
/* enable our own CPIs */
vic_enable_cpi();
cpu_set(boot_cpu_id, cpu_online_map);
cpu_set(boot_cpu_id, cpu_callout_map);
/* loop over all the extended VIC CPUs and boot them. The
* Quad CPUs must be bootstrapped by their extended VIC cpu */
for(i = 0; i < NR_CPUS; i++) {
if(i == boot_cpu_id || !cpu_isset(i, phys_cpu_present_map))
continue;
do_boot_cpu(i);
/* This udelay seems to be needed for the Quad boots
* don't remove unless you know what you're doing */
udelay(1000);
}
/* we could compute the total bogomips here, but why bother?,
* Code added from smpboot.c */
{
unsigned long bogosum = 0;
for (i = 0; i < NR_CPUS; i++)
if (cpu_isset(i, cpu_online_map))
bogosum += cpu_data[i].loops_per_jiffy;
printk(KERN_INFO "Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
cpucount+1,
bogosum/(500000/HZ),
(bogosum/(5000/HZ))%100);
}
voyager_extended_cpus = hweight32(voyager_extended_vic_processors);
printk("VOYAGER: Extended (interrupt handling CPUs): %d, non-extended: %d\n", voyager_extended_cpus, num_booting_cpus() - voyager_extended_cpus);
/* that's it, switch to symmetric mode */
outb(0, VIC_PRIORITY_REGISTER);
outb(0, VIC_CLAIM_REGISTER_0);
outb(0, VIC_CLAIM_REGISTER_1);
VDEBUG(("VOYAGER SMP: Booted with %d CPUs\n", num_booting_cpus()));
}
/* Reload the secondary CPUs task structure (this function does not
* return ) */
void __init
initialize_secondary(void)
{
#if 0
// AC kernels only
set_current(hard_get_current());
#endif
/*
* We don't actually need to load the full TSS,
* basically just the stack pointer and the eip.
*/
asm volatile(
"movl %0,%%esp\n\t"
"jmp *%1"
:
:"r" (current->thread.esp),"r" (current->thread.eip));
}
/* handle a Voyager SYS_INT -- If we don't, the base board will
* panic the system.
*
* System interrupts occur because some problem was detected on the
* various busses. To find out what you have to probe all the
* hardware via the CAT bus. FIXME: At the moment we do nothing. */
fastcall void
smp_vic_sys_interrupt(struct pt_regs *regs)
{
ack_CPI(VIC_SYS_INT);
printk("Voyager SYSTEM INTERRUPT\n");
}
/* Handle a voyager CMN_INT; These interrupts occur either because of
* a system status change or because a single bit memory error
* occurred. FIXME: At the moment, ignore all this. */
fastcall void
smp_vic_cmn_interrupt(struct pt_regs *regs)
{
static __u8 in_cmn_int = 0;
static DEFINE_SPINLOCK(cmn_int_lock);
/* common ints are broadcast, so make sure we only do this once */
_raw_spin_lock(&cmn_int_lock);
if(in_cmn_int)
goto unlock_end;
in_cmn_int++;
_raw_spin_unlock(&cmn_int_lock);
VDEBUG(("Voyager COMMON INTERRUPT\n"));
if(voyager_level == 5)
voyager_cat_do_common_interrupt();
_raw_spin_lock(&cmn_int_lock);
in_cmn_int = 0;
unlock_end:
_raw_spin_unlock(&cmn_int_lock);
ack_CPI(VIC_CMN_INT);
}
/*
* Reschedule call back. Nothing to do, all the work is done
* automatically when we return from the interrupt. */
static void
smp_reschedule_interrupt(void)
{
/* do nothing */
}
static struct mm_struct * flush_mm;
static unsigned long flush_va;
static DEFINE_SPINLOCK(tlbstate_lock);
#define FLUSH_ALL 0xffffffff
/*
* We cannot call mmdrop() because we are in interrupt context,
* instead update mm->cpu_vm_mask.
*
* We need to reload %cr3 since the page tables may be going
* away from under us..
*/
static inline void
leave_mm (unsigned long cpu)
{
if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_OK)
BUG();
cpu_clear(cpu, per_cpu(cpu_tlbstate, cpu).active_mm->cpu_vm_mask);
load_cr3(swapper_pg_dir);
}
/*
* Invalidate call-back
*/
static void
smp_invalidate_interrupt(void)
{
__u8 cpu = smp_processor_id();
if (!test_bit(cpu, &smp_invalidate_needed))
return;
/* This will flood messages. Don't uncomment unless you see
* Problems with cross cpu invalidation
VDEBUG(("VOYAGER SMP: CPU%d received INVALIDATE_CPI\n",
smp_processor_id()));
*/
if (flush_mm == per_cpu(cpu_tlbstate, cpu).active_mm) {
if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_OK) {
if (flush_va == FLUSH_ALL)
local_flush_tlb();
else
__flush_tlb_one(flush_va);
} else
leave_mm(cpu);
}
smp_mb__before_clear_bit();
clear_bit(cpu, &smp_invalidate_needed);
smp_mb__after_clear_bit();
}
/* All the new flush operations for 2.4 */
/* This routine is called with a physical cpu mask */
static void
flush_tlb_others (unsigned long cpumask, struct mm_struct *mm,
unsigned long va)
{
int stuck = 50000;
if (!cpumask)
BUG();
if ((cpumask & cpus_addr(cpu_online_map)[0]) != cpumask)
BUG();
if (cpumask & (1 << smp_processor_id()))
BUG();
if (!mm)
BUG();
spin_lock(&tlbstate_lock);
flush_mm = mm;
flush_va = va;
atomic_set_mask(cpumask, &smp_invalidate_needed);
/*
* We have to send the CPI only to
* CPUs affected.
*/
send_CPI(cpumask, VIC_INVALIDATE_CPI);
while (smp_invalidate_needed) {
mb();
if(--stuck == 0) {
printk("***WARNING*** Stuck doing invalidate CPI (CPU%d)\n", smp_processor_id());
break;
}
}
/* Uncomment only to debug invalidation problems
VDEBUG(("VOYAGER SMP: Completed invalidate CPI (CPU%d)\n", cpu));
*/
flush_mm = NULL;
flush_va = 0;
spin_unlock(&tlbstate_lock);
}
void
flush_tlb_current_task(void)
{
struct mm_struct *mm = current->mm;
unsigned long cpu_mask;
preempt_disable();
cpu_mask = cpus_addr(mm->cpu_vm_mask)[0] & ~(1 << smp_processor_id());
local_flush_tlb();
if (cpu_mask)
flush_tlb_others(cpu_mask, mm, FLUSH_ALL);
preempt_enable();
}
void
flush_tlb_mm (struct mm_struct * mm)
{
unsigned long cpu_mask;
preempt_disable();
cpu_mask = cpus_addr(mm->cpu_vm_mask)[0] & ~(1 << smp_processor_id());
if (current->active_mm == mm) {
if (current->mm)
local_flush_tlb();
else
leave_mm(smp_processor_id());
}
if (cpu_mask)
flush_tlb_others(cpu_mask, mm, FLUSH_ALL);
preempt_enable();
}
void flush_tlb_page(struct vm_area_struct * vma, unsigned long va)
{
struct mm_struct *mm = vma->vm_mm;
unsigned long cpu_mask;
preempt_disable();
cpu_mask = cpus_addr(mm->cpu_vm_mask)[0] & ~(1 << smp_processor_id());
if (current->active_mm == mm) {
if(current->mm)
__flush_tlb_one(va);
else
leave_mm(smp_processor_id());
}
if (cpu_mask)
flush_tlb_others(cpu_mask, mm, va);
preempt_enable();
}
EXPORT_SYMBOL(flush_tlb_page);
/* enable the requested IRQs */
static void
smp_enable_irq_interrupt(void)
{
__u8 irq;
__u8 cpu = get_cpu();
VDEBUG(("VOYAGER SMP: CPU%d enabling irq mask 0x%x\n", cpu,
vic_irq_enable_mask[cpu]));
spin_lock(&vic_irq_lock);
for(irq = 0; irq < 16; irq++) {
if(vic_irq_enable_mask[cpu] & (1<<irq))
enable_local_vic_irq(irq);
}
vic_irq_enable_mask[cpu] = 0;
spin_unlock(&vic_irq_lock);
put_cpu_no_resched();
}
/*
* CPU halt call-back
*/
static void
smp_stop_cpu_function(void *dummy)
{
VDEBUG(("VOYAGER SMP: CPU%d is STOPPING\n", smp_processor_id()));
cpu_clear(smp_processor_id(), cpu_online_map);
local_irq_disable();
for(;;)
halt();
}
static DEFINE_SPINLOCK(call_lock);
struct call_data_struct {
void (*func) (void *info);
void *info;
volatile unsigned long started;
volatile unsigned long finished;
int wait;
};
static struct call_data_struct * call_data;
/* execute a thread on a new CPU. The function to be called must be
* previously set up. This is used to schedule a function for
* execution on all CPU's - set up the function then broadcast a
* function_interrupt CPI to come here on each CPU */
static void
smp_call_function_interrupt(void)
{
void (*func) (void *info) = call_data->func;
void *info = call_data->info;
/* must take copy of wait because call_data may be replaced
* unless the function is waiting for us to finish */
int wait = call_data->wait;
__u8 cpu = smp_processor_id();
/*
* Notify initiating CPU that I've grabbed the data and am
* about to execute the function
*/
mb();
if(!test_and_clear_bit(cpu, &call_data->started)) {
/* If the bit wasn't set, this could be a replay */
printk(KERN_WARNING "VOYAGER SMP: CPU %d received call funtion with no call pending\n", cpu);
return;
}
/*
* At this point the info structure may be out of scope unless wait==1
*/
irq_enter();
(*func)(info);
irq_exit();
if (wait) {
mb();
clear_bit(cpu, &call_data->finished);
}
}
/* Call this function on all CPUs using the function_interrupt above
<func> The function to run. This must be fast and non-blocking.
<info> An arbitrary pointer to pass to the function.
<retry> If true, keep retrying until ready.
<wait> If true, wait until function has completed on other CPUs.
[RETURNS] 0 on success, else a negative status code. Does not return until
remote CPUs are nearly ready to execute <<func>> or are or have executed.
*/
int
smp_call_function (void (*func) (void *info), void *info, int retry,
int wait)
{
struct call_data_struct data;
__u32 mask = cpus_addr(cpu_online_map)[0];
mask &= ~(1<<smp_processor_id());
if (!mask)
return 0;
/* Can deadlock when called with interrupts disabled */
WARN_ON(irqs_disabled());
data.func = func;
data.info = info;
data.started = mask;
data.wait = wait;
if (wait)
data.finished = mask;
spin_lock(&call_lock);
call_data = &data;
wmb();
/* Send a message to all other CPUs and wait for them to respond */
send_CPI_allbutself(VIC_CALL_FUNCTION_CPI);
/* Wait for response */
while (data.started)
barrier();
if (wait)
while (data.finished)
barrier();
spin_unlock(&call_lock);
return 0;
}
EXPORT_SYMBOL(smp_call_function);
/* Sorry about the name. In an APIC based system, the APICs
* themselves are programmed to send a timer interrupt. This is used
* by linux to reschedule the processor. Voyager doesn't have this,
* so we use the system clock to interrupt one processor, which in
* turn, broadcasts a timer CPI to all the others --- we receive that
* CPI here. We don't use this actually for counting so losing
* ticks doesn't matter
*
* FIXME: For those CPU's which actually have a local APIC, we could
* try to use it to trigger this interrupt instead of having to
* broadcast the timer tick. Unfortunately, all my pentium DYADs have
* no local APIC, so I can't do this
*
* This function is currently a placeholder and is unused in the code */
fastcall void
smp_apic_timer_interrupt(struct pt_regs *regs)
{
wrapper_smp_local_timer_interrupt(regs);
}
/* All of the QUAD interrupt GATES */
fastcall void
smp_qic_timer_interrupt(struct pt_regs *regs)
{
ack_QIC_CPI(QIC_TIMER_CPI);
wrapper_smp_local_timer_interrupt(regs);
}
fastcall void
smp_qic_invalidate_interrupt(struct pt_regs *regs)
{
ack_QIC_CPI(QIC_INVALIDATE_CPI);
smp_invalidate_interrupt();
}
fastcall void
smp_qic_reschedule_interrupt(struct pt_regs *regs)
{
ack_QIC_CPI(QIC_RESCHEDULE_CPI);
smp_reschedule_interrupt();
}
fastcall void
smp_qic_enable_irq_interrupt(struct pt_regs *regs)
{
ack_QIC_CPI(QIC_ENABLE_IRQ_CPI);
smp_enable_irq_interrupt();
}
fastcall void
smp_qic_call_function_interrupt(struct pt_regs *regs)
{
ack_QIC_CPI(QIC_CALL_FUNCTION_CPI);
smp_call_function_interrupt();
}
fastcall void
smp_vic_cpi_interrupt(struct pt_regs *regs)
{
__u8 cpu = smp_processor_id();
if(is_cpu_quad())
ack_QIC_CPI(VIC_CPI_LEVEL0);
else
ack_VIC_CPI(VIC_CPI_LEVEL0);
if(test_and_clear_bit(VIC_TIMER_CPI, &vic_cpi_mailbox[cpu]))
wrapper_smp_local_timer_interrupt(regs);
if(test_and_clear_bit(VIC_INVALIDATE_CPI, &vic_cpi_mailbox[cpu]))
smp_invalidate_interrupt();
if(test_and_clear_bit(VIC_RESCHEDULE_CPI, &vic_cpi_mailbox[cpu]))
smp_reschedule_interrupt();
if(test_and_clear_bit(VIC_ENABLE_IRQ_CPI, &vic_cpi_mailbox[cpu]))
smp_enable_irq_interrupt();
if(test_and_clear_bit(VIC_CALL_FUNCTION_CPI, &vic_cpi_mailbox[cpu]))
smp_call_function_interrupt();
}
static void
do_flush_tlb_all(void* info)
{
unsigned long cpu = smp_processor_id();
__flush_tlb_all();
if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_LAZY)
leave_mm(cpu);
}
/* flush the TLB of every active CPU in the system */
void
flush_tlb_all(void)
{
on_each_cpu(do_flush_tlb_all, 0, 1, 1);
}
/* used to set up the trampoline for other CPUs when the memory manager
* is sorted out */
void __init
smp_alloc_memory(void)
{
trampoline_base = (__u32)alloc_bootmem_low_pages(PAGE_SIZE);
if(__pa(trampoline_base) >= 0x93000)
BUG();
}
/* send a reschedule CPI to one CPU by physical CPU number*/
void
smp_send_reschedule(int cpu)
{
send_one_CPI(cpu, VIC_RESCHEDULE_CPI);
}
int
hard_smp_processor_id(void)
{
__u8 i;
__u8 cpumask = inb(VIC_PROC_WHO_AM_I);
if((cpumask & QUAD_IDENTIFIER) == QUAD_IDENTIFIER)
return cpumask & 0x1F;
for(i = 0; i < 8; i++) {
if(cpumask & (1<<i))
return i;
}
printk("** WARNING ** Illegal cpuid returned by VIC: %d", cpumask);
return 0;
}
/* broadcast a halt to all other CPUs */
void
smp_send_stop(void)
{
smp_call_function(smp_stop_cpu_function, NULL, 1, 1);
}
/* this function is triggered in time.c when a clock tick fires
* we need to re-broadcast the tick to all CPUs */
void
smp_vic_timer_interrupt(struct pt_regs *regs)
{
send_CPI_allbutself(VIC_TIMER_CPI);
smp_local_timer_interrupt(regs);
}
/* local (per CPU) timer interrupt. It does both profiling and
* process statistics/rescheduling.
*
* We do profiling in every local tick, statistics/rescheduling
* happen only every 'profiling multiplier' ticks. The default
* multiplier is 1 and it can be changed by writing the new multiplier
* value into /proc/profile.
*/
void
smp_local_timer_interrupt(struct pt_regs * regs)
{
int cpu = smp_processor_id();
long weight;
profile_tick(CPU_PROFILING, regs);
if (--per_cpu(prof_counter, cpu) <= 0) {
/*
* The multiplier may have changed since the last time we got
* to this point as a result of the user writing to
* /proc/profile. In this case we need to adjust the APIC
* timer accordingly.
*
* Interrupts are already masked off at this point.
*/
per_cpu(prof_counter,cpu) = per_cpu(prof_multiplier, cpu);
if (per_cpu(prof_counter, cpu) !=
per_cpu(prof_old_multiplier, cpu)) {
/* FIXME: need to update the vic timer tick here */
per_cpu(prof_old_multiplier, cpu) =
per_cpu(prof_counter, cpu);
}
update_process_times(user_mode_vm(regs));
}
if( ((1<<cpu) & voyager_extended_vic_processors) == 0)
/* only extended VIC processors participate in
* interrupt distribution */
return;
/*
* We take the 'long' return path, and there every subsystem
* grabs the apropriate locks (kernel lock/ irq lock).
*
* we might want to decouple profiling from the 'long path',
* and do the profiling totally in assembly.
*
* Currently this isn't too much of an issue (performance wise),
* we can take more than 100K local irqs per second on a 100 MHz P5.
*/
if((++vic_tick[cpu] & 0x7) != 0)
return;
/* get here every 16 ticks (about every 1/6 of a second) */
/* Change our priority to give someone else a chance at getting
* the IRQ. The algorithm goes like this:
*
* In the VIC, the dynamically routed interrupt is always
* handled by the lowest priority eligible (i.e. receiving
* interrupts) CPU. If >1 eligible CPUs are equal lowest, the
* lowest processor number gets it.
*
* The priority of a CPU is controlled by a special per-CPU
* VIC priority register which is 3 bits wide 0 being lowest
* and 7 highest priority..
*
* Therefore we subtract the average number of interrupts from
* the number we've fielded. If this number is negative, we
* lower the activity count and if it is positive, we raise
* it.
*
* I'm afraid this still leads to odd looking interrupt counts:
* the totals are all roughly equal, but the individual ones
* look rather skewed.
*
* FIXME: This algorithm is total crap when mixed with SMP
* affinity code since we now try to even up the interrupt
* counts when an affinity binding is keeping them on a
* particular CPU*/
weight = (vic_intr_count[cpu]*voyager_extended_cpus
- vic_intr_total) >> 4;
weight += 4;
if(weight > 7)
weight = 7;
if(weight < 0)
weight = 0;
outb((__u8)weight, VIC_PRIORITY_REGISTER);
#ifdef VOYAGER_DEBUG
if((vic_tick[cpu] & 0xFFF) == 0) {
/* print this message roughly every 25 secs */
printk("VOYAGER SMP: vic_tick[%d] = %lu, weight = %ld\n",
cpu, vic_tick[cpu], weight);
}
#endif
}
/* setup the profiling timer */
int
setup_profiling_timer(unsigned int multiplier)
{
int i;
if ( (!multiplier))
return -EINVAL;
/*
* Set the new multiplier for each CPU. CPUs don't start using the
* new values until the next timer interrupt in which they do process
* accounting.
*/
for (i = 0; i < NR_CPUS; ++i)
per_cpu(prof_multiplier, i) = multiplier;
return 0;
}
/* The CPIs are handled in the per cpu 8259s, so they must be
* enabled to be received: FIX: enabling the CPIs in the early
* boot sequence interferes with bug checking; enable them later
* on in smp_init */
#define VIC_SET_GATE(cpi, vector) \
set_intr_gate((cpi) + VIC_DEFAULT_CPI_BASE, (vector))
#define QIC_SET_GATE(cpi, vector) \
set_intr_gate((cpi) + QIC_DEFAULT_CPI_BASE, (vector))
void __init
smp_intr_init(void)
{
int i;
/* initialize the per cpu irq mask to all disabled */
for(i = 0; i < NR_CPUS; i++)
vic_irq_mask[i] = 0xFFFF;
VIC_SET_GATE(VIC_CPI_LEVEL0, vic_cpi_interrupt);
VIC_SET_GATE(VIC_SYS_INT, vic_sys_interrupt);
VIC_SET_GATE(VIC_CMN_INT, vic_cmn_interrupt);
QIC_SET_GATE(QIC_TIMER_CPI, qic_timer_interrupt);
QIC_SET_GATE(QIC_INVALIDATE_CPI, qic_invalidate_interrupt);
QIC_SET_GATE(QIC_RESCHEDULE_CPI, qic_reschedule_interrupt);
QIC_SET_GATE(QIC_ENABLE_IRQ_CPI, qic_enable_irq_interrupt);
QIC_SET_GATE(QIC_CALL_FUNCTION_CPI, qic_call_function_interrupt);
/* now put the VIC descriptor into the first 48 IRQs
*
* This is for later: first 16 correspond to PC IRQs; next 16
* are Primary MC IRQs and final 16 are Secondary MC IRQs */
for(i = 0; i < 48; i++)
irq_desc[i].chip = &vic_irq_type;
}
/* send a CPI at level cpi to a set of cpus in cpuset (set 1 bit per
* processor to receive CPI */
static void
send_CPI(__u32 cpuset, __u8 cpi)
{
int cpu;
__u32 quad_cpuset = (cpuset & voyager_quad_processors);
if(cpi < VIC_START_FAKE_CPI) {
/* fake CPI are only used for booting, so send to the
* extended quads as well---Quads must be VIC booted */
outb((__u8)(cpuset), VIC_CPI_Registers[cpi]);
return;
}
if(quad_cpuset)
send_QIC_CPI(quad_cpuset, cpi);
cpuset &= ~quad_cpuset;
cpuset &= 0xff; /* only first 8 CPUs vaild for VIC CPI */
if(cpuset == 0)
return;
for_each_online_cpu(cpu) {
if(cpuset & (1<<cpu))
set_bit(cpi, &vic_cpi_mailbox[cpu]);
}
if(cpuset)
outb((__u8)cpuset, VIC_CPI_Registers[VIC_CPI_LEVEL0]);
}
/* Acknowledge receipt of CPI in the QIC, clear in QIC hardware and
* set the cache line to shared by reading it.
*
* DON'T make this inline otherwise the cache line read will be
* optimised away
* */
static int
ack_QIC_CPI(__u8 cpi) {
__u8 cpu = hard_smp_processor_id();
cpi &= 7;
outb(1<<cpi, QIC_INTERRUPT_CLEAR1);
return voyager_quad_cpi_addr[cpu]->qic_cpi[cpi].cpi;
}
static void
ack_special_QIC_CPI(__u8 cpi)
{
switch(cpi) {
case VIC_CMN_INT:
outb(QIC_CMN_INT, QIC_INTERRUPT_CLEAR0);
break;
case VIC_SYS_INT:
outb(QIC_SYS_INT, QIC_INTERRUPT_CLEAR0);
break;
}
/* also clear at the VIC, just in case (nop for non-extended proc) */
ack_VIC_CPI(cpi);
}
/* Acknowledge receipt of CPI in the VIC (essentially an EOI) */
static void
ack_VIC_CPI(__u8 cpi)
{
#ifdef VOYAGER_DEBUG
unsigned long flags;
__u16 isr;
__u8 cpu = smp_processor_id();
local_irq_save(flags);
isr = vic_read_isr();
if((isr & (1<<(cpi &7))) == 0) {
printk("VOYAGER SMP: CPU%d lost CPI%d\n", cpu, cpi);
}
#endif
/* send specific EOI; the two system interrupts have
* bit 4 set for a separate vector but behave as the
* corresponding 3 bit intr */
outb_p(0x60|(cpi & 7),0x20);
#ifdef VOYAGER_DEBUG
if((vic_read_isr() & (1<<(cpi &7))) != 0) {
printk("VOYAGER SMP: CPU%d still asserting CPI%d\n", cpu, cpi);
}
local_irq_restore(flags);
#endif
}
/* cribbed with thanks from irq.c */
#define __byte(x,y) (((unsigned char *)&(y))[x])
#define cached_21(cpu) (__byte(0,vic_irq_mask[cpu]))
#define cached_A1(cpu) (__byte(1,vic_irq_mask[cpu]))
static unsigned int
startup_vic_irq(unsigned int irq)
{
enable_vic_irq(irq);
return 0;
}
/* The enable and disable routines. This is where we run into
* conflicting architectural philosophy. Fundamentally, the voyager
* architecture does not expect to have to disable interrupts globally
* (the IRQ controllers belong to each CPU). The processor masquerade
* which is used to start the system shouldn't be used in a running OS
* since it will cause great confusion if two separate CPUs drive to
* the same IRQ controller (I know, I've tried it).
*
* The solution is a variant on the NCR lazy SPL design:
*
* 1) To disable an interrupt, do nothing (other than set the
* IRQ_DISABLED flag). This dares the interrupt actually to arrive.
*
* 2) If the interrupt dares to come in, raise the local mask against
* it (this will result in all the CPU masks being raised
* eventually).
*
* 3) To enable the interrupt, lower the mask on the local CPU and
* broadcast an Interrupt enable CPI which causes all other CPUs to
* adjust their masks accordingly. */
static void
enable_vic_irq(unsigned int irq)
{
/* linux doesn't to processor-irq affinity, so enable on
* all CPUs we know about */
int cpu = smp_processor_id(), real_cpu;
__u16 mask = (1<<irq);
__u32 processorList = 0;
unsigned long flags;
VDEBUG(("VOYAGER: enable_vic_irq(%d) CPU%d affinity 0x%lx\n",
irq, cpu, cpu_irq_affinity[cpu]));
spin_lock_irqsave(&vic_irq_lock, flags);
for_each_online_cpu(real_cpu) {
if(!(voyager_extended_vic_processors & (1<<real_cpu)))
continue;
if(!(cpu_irq_affinity[real_cpu] & mask)) {
/* irq has no affinity for this CPU, ignore */
continue;
}
if(real_cpu == cpu) {
enable_local_vic_irq(irq);
}
else if(vic_irq_mask[real_cpu] & mask) {
vic_irq_enable_mask[real_cpu] |= mask;
processorList |= (1<<real_cpu);
}
}
spin_unlock_irqrestore(&vic_irq_lock, flags);
if(processorList)
send_CPI(processorList, VIC_ENABLE_IRQ_CPI);
}
static void
disable_vic_irq(unsigned int irq)
{
/* lazy disable, do nothing */
}
static void
enable_local_vic_irq(unsigned int irq)
{
__u8 cpu = smp_processor_id();
__u16 mask = ~(1 << irq);
__u16 old_mask = vic_irq_mask[cpu];
vic_irq_mask[cpu] &= mask;
if(vic_irq_mask[cpu] == old_mask)
return;
VDEBUG(("VOYAGER DEBUG: Enabling irq %d in hardware on CPU %d\n",
irq, cpu));
if (irq & 8) {
outb_p(cached_A1(cpu),0xA1);
(void)inb_p(0xA1);
}
else {
outb_p(cached_21(cpu),0x21);
(void)inb_p(0x21);
}
}
static void
disable_local_vic_irq(unsigned int irq)
{
__u8 cpu = smp_processor_id();
__u16 mask = (1 << irq);
__u16 old_mask = vic_irq_mask[cpu];
if(irq == 7)
return;
vic_irq_mask[cpu] |= mask;
if(old_mask == vic_irq_mask[cpu])
return;
VDEBUG(("VOYAGER DEBUG: Disabling irq %d in hardware on CPU %d\n",
irq, cpu));
if (irq & 8) {
outb_p(cached_A1(cpu),0xA1);
(void)inb_p(0xA1);
}
else {
outb_p(cached_21(cpu),0x21);
(void)inb_p(0x21);
}
}
/* The VIC is level triggered, so the ack can only be issued after the
* interrupt completes. However, we do Voyager lazy interrupt
* handling here: It is an extremely expensive operation to mask an
* interrupt in the vic, so we merely set a flag (IRQ_DISABLED). If
* this interrupt actually comes in, then we mask and ack here to push
* the interrupt off to another CPU */
static void
before_handle_vic_irq(unsigned int irq)
{
irq_desc_t *desc = irq_desc + irq;
__u8 cpu = smp_processor_id();
_raw_spin_lock(&vic_irq_lock);
vic_intr_total++;
vic_intr_count[cpu]++;
if(!(cpu_irq_affinity[cpu] & (1<<irq))) {
/* The irq is not in our affinity mask, push it off
* onto another CPU */
VDEBUG(("VOYAGER DEBUG: affinity triggered disable of irq %d on cpu %d\n",
irq, cpu));
disable_local_vic_irq(irq);
/* set IRQ_INPROGRESS to prevent the handler in irq.c from
* actually calling the interrupt routine */
desc->status |= IRQ_REPLAY | IRQ_INPROGRESS;
} else if(desc->status & IRQ_DISABLED) {
/* Damn, the interrupt actually arrived, do the lazy
* disable thing. The interrupt routine in irq.c will
* not handle a IRQ_DISABLED interrupt, so nothing more
* need be done here */
VDEBUG(("VOYAGER DEBUG: lazy disable of irq %d on CPU %d\n",
irq, cpu));
disable_local_vic_irq(irq);
desc->status |= IRQ_REPLAY;
} else {
desc->status &= ~IRQ_REPLAY;
}
_raw_spin_unlock(&vic_irq_lock);
}
/* Finish the VIC interrupt: basically mask */
static void
after_handle_vic_irq(unsigned int irq)
{
irq_desc_t *desc = irq_desc + irq;
_raw_spin_lock(&vic_irq_lock);
{
unsigned int status = desc->status & ~IRQ_INPROGRESS;
#ifdef VOYAGER_DEBUG
__u16 isr;
#endif
desc->status = status;
if ((status & IRQ_DISABLED))
disable_local_vic_irq(irq);
#ifdef VOYAGER_DEBUG
/* DEBUG: before we ack, check what's in progress */
isr = vic_read_isr();
if((isr & (1<<irq) && !(status & IRQ_REPLAY)) == 0) {
int i;
__u8 cpu = smp_processor_id();
__u8 real_cpu;
int mask; /* Um... initialize me??? --RR */
printk("VOYAGER SMP: CPU%d lost interrupt %d\n",
cpu, irq);
for_each_possible_cpu(real_cpu, mask) {
outb(VIC_CPU_MASQUERADE_ENABLE | real_cpu,
VIC_PROCESSOR_ID);
isr = vic_read_isr();
if(isr & (1<<irq)) {
printk("VOYAGER SMP: CPU%d ack irq %d\n",
real_cpu, irq);
ack_vic_irq(irq);
}
outb(cpu, VIC_PROCESSOR_ID);
}
}
#endif /* VOYAGER_DEBUG */
/* as soon as we ack, the interrupt is eligible for
* receipt by another CPU so everything must be in
* order here */
ack_vic_irq(irq);
if(status & IRQ_REPLAY) {
/* replay is set if we disable the interrupt
* in the before_handle_vic_irq() routine, so
* clear the in progress bit here to allow the
* next CPU to handle this correctly */
desc->status &= ~(IRQ_REPLAY | IRQ_INPROGRESS);
}
#ifdef VOYAGER_DEBUG
isr = vic_read_isr();
if((isr & (1<<irq)) != 0)
printk("VOYAGER SMP: after_handle_vic_irq() after ack irq=%d, isr=0x%x\n",
irq, isr);
#endif /* VOYAGER_DEBUG */
}
_raw_spin_unlock(&vic_irq_lock);
/* All code after this point is out of the main path - the IRQ
* may be intercepted by another CPU if reasserted */
}
/* Linux processor - interrupt affinity manipulations.
*
* For each processor, we maintain a 32 bit irq affinity mask.
* Initially it is set to all 1's so every processor accepts every
* interrupt. In this call, we change the processor's affinity mask:
*
* Change from enable to disable:
*
* If the interrupt ever comes in to the processor, we will disable it
* and ack it to push it off to another CPU, so just accept the mask here.
*
* Change from disable to enable:
*
* change the mask and then do an interrupt enable CPI to re-enable on
* the selected processors */
void
set_vic_irq_affinity(unsigned int irq, cpumask_t mask)
{
/* Only extended processors handle interrupts */
unsigned long real_mask;
unsigned long irq_mask = 1 << irq;
int cpu;
real_mask = cpus_addr(mask)[0] & voyager_extended_vic_processors;
if(cpus_addr(mask)[0] == 0)
/* can't have no cpu's to accept the interrupt -- extremely
* bad things will happen */
return;
if(irq == 0)
/* can't change the affinity of the timer IRQ. This
* is due to the constraint in the voyager
* architecture that the CPI also comes in on and IRQ
* line and we have chosen IRQ0 for this. If you
* raise the mask on this interrupt, the processor
* will no-longer be able to accept VIC CPIs */
return;
if(irq >= 32)
/* You can only have 32 interrupts in a voyager system
* (and 32 only if you have a secondary microchannel
* bus) */
return;
for_each_online_cpu(cpu) {
unsigned long cpu_mask = 1 << cpu;
if(cpu_mask & real_mask) {
/* enable the interrupt for this cpu */
cpu_irq_affinity[cpu] |= irq_mask;
} else {
/* disable the interrupt for this cpu */
cpu_irq_affinity[cpu] &= ~irq_mask;
}
}
/* this is magic, we now have the correct affinity maps, so
* enable the interrupt. This will send an enable CPI to
* those cpu's who need to enable it in their local masks,
* causing them to correct for the new affinity . If the
* interrupt is currently globally disabled, it will simply be
* disabled again as it comes in (voyager lazy disable). If
* the affinity map is tightened to disable the interrupt on a
* cpu, it will be pushed off when it comes in */
enable_vic_irq(irq);
}
static void
ack_vic_irq(unsigned int irq)
{
if (irq & 8) {
outb(0x62,0x20); /* Specific EOI to cascade */
outb(0x60|(irq & 7),0xA0);
} else {
outb(0x60 | (irq & 7),0x20);
}
}
/* enable the CPIs. In the VIC, the CPIs are delivered by the 8259
* but are not vectored by it. This means that the 8259 mask must be
* lowered to receive them */
static __init void
vic_enable_cpi(void)
{
__u8 cpu = smp_processor_id();
/* just take a copy of the current mask (nop for boot cpu) */
vic_irq_mask[cpu] = vic_irq_mask[boot_cpu_id];
enable_local_vic_irq(VIC_CPI_LEVEL0);
enable_local_vic_irq(VIC_CPI_LEVEL1);
/* for sys int and cmn int */
enable_local_vic_irq(7);
if(is_cpu_quad()) {
outb(QIC_DEFAULT_MASK0, QIC_MASK_REGISTER0);
outb(QIC_CPI_ENABLE, QIC_MASK_REGISTER1);
VDEBUG(("VOYAGER SMP: QIC ENABLE CPI: CPU%d: MASK 0x%x\n",
cpu, QIC_CPI_ENABLE));
}
VDEBUG(("VOYAGER SMP: ENABLE CPI: CPU%d: MASK 0x%x\n",
cpu, vic_irq_mask[cpu]));
}
void
voyager_smp_dump()
{
int old_cpu = smp_processor_id(), cpu;
/* dump the interrupt masks of each processor */
for_each_online_cpu(cpu) {
__u16 imr, isr, irr;
unsigned long flags;
local_irq_save(flags);
outb(VIC_CPU_MASQUERADE_ENABLE | cpu, VIC_PROCESSOR_ID);
imr = (inb(0xa1) << 8) | inb(0x21);
outb(0x0a, 0xa0);
irr = inb(0xa0) << 8;
outb(0x0a, 0x20);
irr |= inb(0x20);
outb(0x0b, 0xa0);
isr = inb(0xa0) << 8;
outb(0x0b, 0x20);
isr |= inb(0x20);
outb(old_cpu, VIC_PROCESSOR_ID);
local_irq_restore(flags);
printk("\tCPU%d: mask=0x%x, IMR=0x%x, IRR=0x%x, ISR=0x%x\n",
cpu, vic_irq_mask[cpu], imr, irr, isr);
#if 0
/* These lines are put in to try to unstick an un ack'd irq */
if(isr != 0) {
int irq;
for(irq=0; irq<16; irq++) {
if(isr & (1<<irq)) {
printk("\tCPU%d: ack irq %d\n",
cpu, irq);
local_irq_save(flags);
outb(VIC_CPU_MASQUERADE_ENABLE | cpu,
VIC_PROCESSOR_ID);
ack_vic_irq(irq);
outb(old_cpu, VIC_PROCESSOR_ID);
local_irq_restore(flags);
}
}
}
#endif
}
}
void
smp_voyager_power_off(void *dummy)
{
if(smp_processor_id() == boot_cpu_id)
voyager_power_off();
else
smp_stop_cpu_function(NULL);
}
void __init
smp_prepare_cpus(unsigned int max_cpus)
{
/* FIXME: ignore max_cpus for now */
smp_boot_cpus();
}
void __devinit smp_prepare_boot_cpu(void)
{
cpu_set(smp_processor_id(), cpu_online_map);
cpu_set(smp_processor_id(), cpu_callout_map);
cpu_set(smp_processor_id(), cpu_possible_map);
cpu_set(smp_processor_id(), cpu_present_map);
}
int __devinit
__cpu_up(unsigned int cpu)
{
/* This only works at boot for x86. See "rewrite" above. */
if (cpu_isset(cpu, smp_commenced_mask))
return -ENOSYS;
/* In case one didn't come up */
if (!cpu_isset(cpu, cpu_callin_map))
return -EIO;
/* Unleash the CPU! */
cpu_set(cpu, smp_commenced_mask);
while (!cpu_isset(cpu, cpu_online_map))
mb();
return 0;
}
void __init
smp_cpus_done(unsigned int max_cpus)
{
zap_low_mappings();
}
