/*
* Copyright (C) 2001 Mike Corrigan IBM Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/bootmem.h>
#include <linux/seq_file.h>
#include <linux/proc_fs.h>
#include <linux/module.h>
#include <asm/system.h>
#include <asm/paca.h>
#include <asm/firmware.h>
#include <asm/iseries/it_lp_queue.h>
#include <asm/iseries/hv_lp_event.h>
#include <asm/iseries/hv_call_event.h>
#include "it_lp_naca.h"
/*
* The LpQueue is used to pass event data from the hypervisor to
* the partition. This is where I/O interrupt events are communicated.
*
* It is written to by the hypervisor so cannot end up in the BSS.
*/
struct hvlpevent_queue hvlpevent_queue __attribute__((__section__(".data")));
DEFINE_PER_CPU(unsigned long[HvLpEvent_Type_NumTypes], hvlpevent_counts);
static char *event_types[HvLpEvent_Type_NumTypes] = {
"Hypervisor",
"Machine Facilities",
"Session Manager",
"SPD I/O",
"Virtual Bus",
"PCI I/O",
"RIO I/O",
"Virtual Lan",
"Virtual I/O"
};
/* Array of LpEvent handler functions */
static LpEventHandler lpEventHandler[HvLpEvent_Type_NumTypes];
static unsigned lpEventHandlerPaths[HvLpEvent_Type_NumTypes];
static struct HvLpEvent * get_next_hvlpevent(void)
{
struct HvLpEvent * event;
event = (struct HvLpEvent *)hvlpevent_queue.hq_current_event;
if (hvlpevent_is_valid(event)) {
/* rmb() needed only for weakly consistent machines (regatta) */
rmb();
/* Set pointer to next potential event */
hvlpevent_queue.hq_current_event += ((event->xSizeMinus1 +
IT_LP_EVENT_ALIGN) / IT_LP_EVENT_ALIGN) *
IT_LP_EVENT_ALIGN;
/* Wrap to beginning if no room at end */
if (hvlpevent_queue.hq_current_event >
hvlpevent_queue.hq_last_event) {
hvlpevent_queue.hq_current_event =
hvlpevent_queue.hq_event_stack;
}
} else {
event = NULL;
}
return event;
}
static unsigned long spread_lpevents = NR_CPUS;
int hvlpevent_is_pending(void)
{
struct HvLpEvent *next_event;
if (smp_processor_id() >= spread_lpevents)
return 0;
next_event = (struct HvLpEvent *)hvlpevent_queue.hq_current_event;
return hvlpevent_is_valid(next_event) ||
hvlpevent_queue.hq_overflow_pending;
}
static void hvlpevent_clear_valid(struct HvLpEvent * event)
{
/* Tell the Hypervisor that we're done with this event.
* Also clear bits within this event that might look like valid bits.
* ie. on 64-byte boundaries.
*/
struct HvLpEvent *tmp;
unsigned extra = ((event->xSizeMinus1 + IT_LP_EVENT_ALIGN) /
IT_LP_EVENT_ALIGN) - 1;
switch (extra) {
case 3:
tmp = (struct HvLpEvent*)((char*)event + 3 * IT_LP_EVENT_ALIGN);
hvlpevent_invalidate(tmp);
case 2:
tmp = (struct HvLpEvent*)((char*)event + 2 * IT_LP_EVENT_ALIGN);
hvlpevent_invalidate(tmp);
case 1:
tmp = (struct HvLpEvent*)((char*)event + 1 * IT_LP_EVENT_ALIGN);
hvlpevent_invalidate(tmp);
}
mb();
hvlpevent_invalidate(event);
}
void process_hvlpevents(void)
{
struct HvLpEvent * event;
restart:
/* If we have recursed, just return */
if (!spin_trylock(&hvlpevent_queue.hq_lock))
return;
for (;;) {
event = get_next_hvlpevent();
if (event) {
/* Call appropriate handler here, passing
* a pointer to the LpEvent. The handler
* must make a copy of the LpEvent if it
* needs it in a bottom half. (perhaps for
* an ACK)
*
* Handlers are responsible for ACK processing
*
* The Hypervisor guarantees that LpEvents will
* only be delivered with types that we have
* registered for, so no type check is necessary
* here!
*/
if (event->xType < HvLpEvent_Type_NumTypes)
__get_cpu_var(hvlpevent_counts)[event->xType]++;
if (event->xType < HvLpEvent_Type_NumTypes &&
lpEventHandler[event->xType])
lpEventHandler[event->xType](event);
else {
u8 type = event->xType;
/*
* Don't printk in the spinlock as printk
* may require ack events form the HV to send
* any characters there.
*/
hvlpevent_clear_valid(event);
spin_unlock(&hvlpevent_queue.hq_lock);
printk(KERN_INFO
"Unexpected Lp Event type=%d\n", type);
goto restart;
}
hvlpevent_clear_valid(event);
} else if (hvlpevent_queue.hq_overflow_pending)
/*
* No more valid events. If overflow events are
* pending process them
*/
HvCallEvent_getOverflowLpEvents(hvlpevent_queue.hq_index);
else
break;
}
spin_unlock(&hvlpevent_queue.hq_lock);
}
static int set_spread_lpevents(char *str)
{
unsigned long val = simple_strtoul(str, NULL, 0);
/*
* The parameter is the number of processors to share in processing
* lp events.
*/
if (( val > 0) && (val <= NR_CPUS)) {
spread_lpevents = val;
printk("lpevent processing spread over %ld processors\n", val);
} else {
printk("invalid spread_lpevents %ld\n", val);
}
return 1;
}
__setup("spread_lpevents=", set_spread_lpevents);
void __init setup_hvlpevent_queue(void)
{
void *eventStack;
spin_lock_init(&hvlpevent_queue.hq_lock);
/* Allocate a page for the Event Stack. */
eventStack = alloc_bootmem_pages(IT_LP_EVENT_STACK_SIZE);
memset(eventStack, 0, IT_LP_EVENT_STACK_SIZE);
/* Invoke the hypervisor to initialize the event stack */
HvCallEvent_setLpEventStack(0, eventStack, IT_LP_EVENT_STACK_SIZE);
hvlpevent_queue.hq_event_stack = eventStack;
hvlpevent_queue.hq_current_event = eventStack;
hvlpevent_queue.hq_last_event = (char *)eventStack +
(IT_LP_EVENT_STACK_SIZE - IT_LP_EVENT_MAX_SIZE);
hvlpevent_queue.hq_index = 0;
}
/* Register a handler for an LpEvent type */
int HvLpEvent_registerHandler(HvLpEvent_Type eventType, LpEventHandler handler)
{
if (eventType < HvLpEvent_Type_NumTypes) {
lpEventHandler[eventType] = handler;
return 0;
}
return 1;
}
EXPORT_SYMBOL(HvLpEvent_registerHandler);
int HvLpEvent_unregisterHandler(HvLpEvent_Type eventType)
{
might_sleep();
if (eventType < HvLpEvent_Type_NumTypes) {
if (!lpEventHandlerPaths[eventType]) {
lpEventHandler[eventType] = NULL;
/*
* We now sleep until all other CPUs have scheduled.
* This ensures that the deletion is seen by all
* other CPUs, and that the deleted handler isn't
* still running on another CPU when we return.
*/
synchronize_sched();
return 0;
}
}
return 1;
}
EXPORT_SYMBOL(HvLpEvent_unregisterHandler);
/*
* lpIndex is the partition index of the target partition.
* needed only for VirtualIo, VirtualLan and SessionMgr. Zero
* indicates to use our partition index - for the other types.
*/
int HvLpEvent_openPath(HvLpEvent_Type eventType, HvLpIndex lpIndex)
{
if ((eventType < HvLpEvent_Type_NumTypes) &&
lpEventHandler[eventType]) {
if (lpIndex == 0)
lpIndex = itLpNaca.xLpIndex;
HvCallEvent_openLpEventPath(lpIndex, eventType);
++lpEventHandlerPaths[eventType];
return 0;
}
return 1;
}
int HvLpEvent_closePath(HvLpEvent_Type eventType, HvLpIndex lpIndex)
{
if ((eventType < HvLpEvent_Type_NumTypes) &&
lpEventHandler[eventType] &&
lpEventHandlerPaths[eventType]) {
if (lpIndex == 0)
lpIndex = itLpNaca.xLpIndex;
HvCallEvent_closeLpEventPath(lpIndex, eventType);
--lpEventHandlerPaths[eventType];
return 0;
}
return 1;
}
static int proc_lpevents_show(struct seq_file *m, void *v)
{
int cpu, i;
unsigned long sum;
static unsigned long cpu_totals[NR_CPUS];
/* FIXME: do we care that there's no locking here? */
sum = 0;
for_each_online_cpu(cpu) {
cpu_totals[cpu] = 0;
for (i = 0; i < HvLpEvent_Type_NumTypes; i++) {
cpu_totals[cpu] += per_cpu(hvlpevent_counts, cpu)[i];
}
sum += cpu_totals[cpu];
}
seq_printf(m, "LpEventQueue 0\n");
seq_printf(m, " events processed:\t%lu\n", sum);
for (i = 0; i < HvLpEvent_Type_NumTypes; ++i) {
sum = 0;
for_each_online_cpu(cpu) {
sum += per_cpu(hvlpevent_counts, cpu)[i];
}
seq_printf(m, " %-20s %10lu\n", event_types[i], sum);
}
seq_printf(m, "\n events processed by processor:\n");
for_each_online_cpu(cpu) {
seq_printf(m, " CPU%02d %10lu\n", cpu, cpu_totals[cpu]);
}
return 0;
}
static int proc_lpevents_open(struct inode *inode, struct file *file)
{
return single_open(file, proc_lpevents_show, NULL);
}
static const struct file_operations proc_lpevents_operations = {
.open = proc_lpevents_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int __init proc_lpevents_init(void)
{
if (!firmware_has_feature(FW_FEATURE_ISERIES))
return 0;
proc_create("iSeries/lpevents", S_IFREG|S_IRUGO, NULL,
&proc_lpevents_operations);
return 0;
}
__initcall(proc_lpevents_init);
