Add hardware interrupt notification mechanism

This allows privileged userland drivers to get notifications of hardware
interrupts.

Initial work by Zheng Da, reworked by Damien Zammit and myself.

* Makefrag.am (libkernel_a_SOURCES): Add device/intr.c and
device/intr.h.
(include_device_HEADERS): Add include/device/notify.defs and
include/device/notify.h.
* device/dev_hdr.h (name_equal): Add declaration.
* device/ds_routines.c: Include <device/intr.h>
(ds_device_intr_register, ds_device_intr_ack): New functions.
* device/intr.c, device/intr.h: New files.
* doc/mach.texi (Device Interrupt): New section.
* i386/Makefrag.am (libkernel_a_SOURCES): Add i386/i386/irq.c and
i386/i386/irq.h.
* i386/i386/irq.c, i386/i386/irq.h: New files.
* i386/i386at/conf.c: Include <device/intr.h>.
(irqname): New macro.
(dev_name_list): Add irq device.
* include/device/device.defs (device_intr_register, device_intr_ack):
New RPCs.
* include/device/notify.defs, include/device/notify.h: New files.
* kern/startup.c: Include <device/intr.h>
(start_kernel_threads): Start intr_thread thread.
* linux/dev/arch/i386/kernel/irq.c: Include <device/intr.h>
(linux_action): Add user_intr field.
(linux_intr): Call user_intr action if any.
(mask_irq, unmask_irq): Move functions to i386/i386/pic.c
(__disable_irq, __enable_irq): Move functions to i386/i386/irq.c.
(install_user_intr_handler): New function.
(request_irq): Initialize user_intr field.
* linux/src/include/asm-i386/irq.h (__disable_irq, __enable_irq): Remove
prototypes.
* i386/i386/pic.c (mask_irq, unmask_irq): New functions.
* i386/i386/pic.h (mask_irq, unmask_irq): New prototypes.

1 files changed, 62 insertions, 0 deletions

diff --git a/device/intr.h b/device/intr.h
new file mode 100644
index 00000000..cd3e0bce
--- /dev/null
+++ b/device/intr.h
@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2010, 2011, 2019 Free Software Foundation, Inc.
+ *
+ * Permission to use, copy, modify and distribute this software and its
+ * documentation is hereby granted, provided that both the copyright
+ * notice and this permission notice appear in all copies of the
+ * software, derivative works or modified versions, and any portions
+ * thereof, and that both notices appear in supporting documentation.
+ *
+ * THE FREE SOFTWARE FOUNDATIONALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
+ * CONDITION.  THE FREE SOFTWARE FOUNDATION DISCLAIMS ANY LIABILITY OF ANY KIND
+ * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ */
+
+#ifndef __INTR_H__
+#define __INTR_H__
+
+#ifndef MACH_XEN
+
+#include <mach/kern_return.h>
+#include <mach/port.h>
+#include <kern/queue.h>
+#include <ipc/ipc_port.h>
+#include <device/conf.h>
+
+#define DEVICE_NOTIFY_MSGH_SEQNO 0
+
+#include <sys/types.h>
+
+struct irqdev;
+#include <machine/irq.h>
+
+typedef struct {
+  queue_chain_t chain;
+  int interrupts; /* Number of interrupts occurred since last run of intr_thread */
+  int n_unacked;  /* Number of times irqs were disabled for this */
+  ipc_port_t dst_port; /* Notification port */
+  int id; /* Mapping to machine dependent irq_t array elem */
+} user_intr_t;
+
+struct irqdev {
+  char *name;
+  void (*irqdev_ack)(struct irqdev *dev, int id);
+
+  queue_head_t *intr_queue;
+  int tot_num_intr; /* Total number of unprocessed interrupts */
+
+  /* Machine dependent */
+  irq_t irq[NINTR];
+};
+
+extern queue_head_t main_intr_queue;
+extern int install_user_intr_handler (struct irqdev *dev, int id, unsigned long flags, user_intr_t *e);
+extern int deliver_user_intr (struct irqdev *dev, int id, user_intr_t *e);
+extern user_intr_t *insert_intr_entry (struct irqdev *dev, int id, ipc_port_t receive_port);
+
+void intr_thread (void);
+kern_return_t irq_acknowledge (ipc_port_t receive_port);
+
+#endif /* MACH_XEN */
+
+#endif