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-rw-r--r--arch/powerpc/platforms/iseries/lpevents.c325
1 files changed, 325 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/iseries/lpevents.c b/arch/powerpc/platforms/iseries/lpevents.c
new file mode 100644
index 00000000000..e9fb98bf895
--- /dev/null
+++ b/arch/powerpc/platforms/iseries/lpevents.c
@@ -0,0 +1,325 @@
+/*
+ * 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/iseries/it_lp_queue.h>
+#include <asm/iseries/hv_lp_event.h>
+#include <asm/iseries/hv_call_event.h>
+#include <asm/iseries/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.xSlicCurEventPtr;
+
+ if (event->xFlags.xValid) {
+ /* rmb() needed only for weakly consistent machines (regatta) */
+ rmb();
+ /* Set pointer to next potential event */
+ hvlpevent_queue.xSlicCurEventPtr += ((event->xSizeMinus1 +
+ LpEventAlign) / LpEventAlign) * LpEventAlign;
+
+ /* Wrap to beginning if no room at end */
+ if (hvlpevent_queue.xSlicCurEventPtr >
+ hvlpevent_queue.xSlicLastValidEventPtr) {
+ hvlpevent_queue.xSlicCurEventPtr =
+ hvlpevent_queue.xSlicEventStackPtr;
+ }
+ } 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.xSlicCurEventPtr;
+
+ return next_event->xFlags.xValid |
+ hvlpevent_queue.xPlicOverflowIntPending;
+}
+
+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 + LpEventAlign) /
+ LpEventAlign) - 1;
+
+ switch (extra) {
+ case 3:
+ tmp = (struct HvLpEvent*)((char*)event + 3 * LpEventAlign);
+ tmp->xFlags.xValid = 0;
+ case 2:
+ tmp = (struct HvLpEvent*)((char*)event + 2 * LpEventAlign);
+ tmp->xFlags.xValid = 0;
+ case 1:
+ tmp = (struct HvLpEvent*)((char*)event + 1 * LpEventAlign);
+ tmp->xFlags.xValid = 0;
+ }
+
+ mb();
+
+ event->xFlags.xValid = 0;
+}
+
+void process_hvlpevents(struct pt_regs *regs)
+{
+ struct HvLpEvent * event;
+
+ /* If we have recursed, just return */
+ if (!spin_trylock(&hvlpevent_queue.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, regs);
+ else
+ printk(KERN_INFO "Unexpected Lp Event type=%d\n", event->xType );
+
+ hvlpevent_clear_valid(event);
+ } else if (hvlpevent_queue.xPlicOverflowIntPending)
+ /*
+ * No more valid events. If overflow events are
+ * pending process them
+ */
+ HvCallEvent_getOverflowLpEvents(hvlpevent_queue.xIndex);
+ else
+ break;
+ }
+
+ spin_unlock(&hvlpevent_queue.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 setup_hvlpevent_queue(void)
+{
+ void *eventStack;
+
+ /* Allocate a page for the Event Stack. */
+ eventStack = alloc_bootmem_pages(LpEventStackSize);
+ memset(eventStack, 0, LpEventStackSize);
+
+ /* Invoke the hypervisor to initialize the event stack */
+ HvCallEvent_setLpEventStack(0, eventStack, LpEventStackSize);
+
+ hvlpevent_queue.xSlicEventStackPtr = (char *)eventStack;
+ hvlpevent_queue.xSlicCurEventPtr = (char *)eventStack;
+ hvlpevent_queue.xSlicLastValidEventPtr = (char *)eventStack +
+ (LpEventStackSize - LpEventMaxSize);
+ hvlpevent_queue.xIndex = 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_rcu();
+ 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 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)
+{
+ struct proc_dir_entry *e;
+
+ e = create_proc_entry("iSeries/lpevents", S_IFREG|S_IRUGO, NULL);
+ if (e)
+ e->proc_fops = &proc_lpevents_operations;
+
+ return 0;
+}
+__initcall(proc_lpevents_init);
+