1 files changed, 118 insertions, 0 deletions
diff --git a/old/xenolinux-2.4.16-sparse/arch/xeno/kernel/hypervisor.c b/old/xenolinux-2.4.16-sparse/arch/xeno/kernel/hypervisor.c
new file mode 100644
index 0000000000..c49087173f
--- /dev/null
+++ b/old/xenolinux-2.4.16-sparse/arch/xeno/kernel/hypervisor.c
@@ -0,0 +1,118 @@
+/******************************************************************************
+ * hypervisor.c
+ * 
+ * Communication to/from hypervisor.
+ * 
+ * Copyright (c) 2002, K A Fraser
+ */
+
+#include <linux/config.h>
+#include <asm/atomic.h>
+#include <linux/irq.h>
+#include <asm/hypervisor.h>
+#include <asm/system.h>
+#include <asm/ptrace.h>
+
+static unsigned long event_mask = 0;
+
+void frobb(void) {}
+
+void do_hypervisor_callback(struct pt_regs *regs)
+{
+    unsigned long events, flags;
+    shared_info_t *shared = HYPERVISOR_shared_info;
+
+    do {
+        /* Specialised local_irq_save(). */
+        flags = shared->events_enable;
+        shared->events_enable = 0;
+        barrier();
+
+        events  = xchg(&shared->events, 0);
+        events &= event_mask;
+
+        __asm__ __volatile__ (
+            "   push %1                            ;"
+            "   sub  $4,%%esp                      ;"
+            "   jmp  2f                            ;"
+            "1: btrl %%eax,%0                      ;" /* clear bit     */
+            "   mov  %%eax,(%%esp)                 ;"
+            "   call do_IRQ                        ;" /* do_IRQ(event) */
+            "2: bsfl %0,%%eax                      ;" /* %eax == bit # */
+            "   jnz  1b                            ;"
+            "   add  $8,%%esp                      ;"
+            /* we use %ebx because it is callee-saved */
+            : : "b" (events), "r" (regs)
+            /* clobbered by callback function calls */
+            : "eax", "ecx", "edx", "memory" ); 
+
+        /* Specialised local_irq_restore(). */
+        shared->events_enable = flags;
+        barrier();
+    }
+    while ( shared->events );
+}
+
+
+
+/*
+ * Define interface to generic handling in irq.c
+ */
+
+static unsigned int startup_hypervisor_event(unsigned int irq)
+{
+    set_bit(irq, &event_mask);
+    return 0;
+}
+
+static void shutdown_hypervisor_event(unsigned int irq)
+{
+    clear_bit(irq, &event_mask);
+}
+
+static void enable_hypervisor_event(unsigned int irq)
+{
+    set_bit(irq, &event_mask);
+}
+
+static void disable_hypervisor_event(unsigned int irq)
+{
+    clear_bit(irq, &event_mask);
+}
+
+static void ack_hypervisor_event(unsigned int irq)
+{
+    if ( !(event_mask & (1<<irq)) )
+    {
+        printk("Unexpected hypervisor event %d\n", irq);
+        atomic_inc(&irq_err_count);
+    }
+}
+
+static void end_hypervisor_event(unsigned int irq)
+{
+}
+
+static struct hw_interrupt_type hypervisor_irq_type = {
+    "Hypervisor-event",
+    startup_hypervisor_event,
+    shutdown_hypervisor_event,
+    enable_hypervisor_event,
+    disable_hypervisor_event,
+    ack_hypervisor_event,
+    end_hypervisor_event,
+    NULL
+};
+
+void __init init_IRQ(void)
+{
+    int i;
+
+    for ( i = 0; i < NR_IRQS; i++ )
+    {
+        irq_desc[i].status  = IRQ_DISABLED;
+        irq_desc[i].action  = 0;
+        irq_desc[i].depth   = 1;
+        irq_desc[i].handler = &hypervisor_irq_type;
+    }
+}