xen pvfb: Para-virtual framebuffer, keyboard and pointer driver

This is a pair of Xen para-virtual frontend device drivers:
drivers/video/xen-fbfront.c provides a framebuffer, and
drivers/input/xen-kbdfront provides keyboard and mouse.

The backends run in dom0 user space.

The two drivers are not in two separate patches, because the
intermediate step (one driver, not the other) is somewhat problematic:
the backend in dom0 needs both drivers, and will refuse to complete
device initialization unless they're both present.

Signed-off-by: Markus Armbruster <armbru@redhat.com>

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 124 insertions, 0 deletions

diff --git a/include/xen/interface/io/fbif.h b/include/xen/interface/io/fbif.h
new file mode 100644
index 00000000000..5a934dd7796
--- /dev/null
+++ b/include/xen/interface/io/fbif.h
@@ -0,0 +1,124 @@
+/*
+ * fbif.h -- Xen virtual frame buffer device
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Copyright (C) 2005 Anthony Liguori <aliguori@us.ibm.com>
+ * Copyright (C) 2006 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
+ */
+
+#ifndef __XEN_PUBLIC_IO_FBIF_H__
+#define __XEN_PUBLIC_IO_FBIF_H__
+
+/* Out events (frontend -> backend) */
+
+/*
+ * Out events may be sent only when requested by backend, and receipt
+ * of an unknown out event is an error.
+ */
+
+/* Event type 1 currently not used */
+/*
+ * Framebuffer update notification event
+ * Capable frontend sets feature-update in xenstore.
+ * Backend requests it by setting request-update in xenstore.
+ */
+#define XENFB_TYPE_UPDATE 2
+
+struct xenfb_update {
+	uint8_t type;		/* XENFB_TYPE_UPDATE */
+	int32_t x;		/* source x */
+	int32_t y;		/* source y */
+	int32_t width;		/* rect width */
+	int32_t height;		/* rect height */
+};
+
+#define XENFB_OUT_EVENT_SIZE 40
+
+union xenfb_out_event {
+	uint8_t type;
+	struct xenfb_update update;
+	char pad[XENFB_OUT_EVENT_SIZE];
+};
+
+/* In events (backend -> frontend) */
+
+/*
+ * Frontends should ignore unknown in events.
+ * No in events currently defined.
+ */
+
+#define XENFB_IN_EVENT_SIZE 40
+
+union xenfb_in_event {
+	uint8_t type;
+	char pad[XENFB_IN_EVENT_SIZE];
+};
+
+/* shared page */
+
+#define XENFB_IN_RING_SIZE 1024
+#define XENFB_IN_RING_LEN (XENFB_IN_RING_SIZE / XENFB_IN_EVENT_SIZE)
+#define XENFB_IN_RING_OFFS 1024
+#define XENFB_IN_RING(page) \
+	((union xenfb_in_event *)((char *)(page) + XENFB_IN_RING_OFFS))
+#define XENFB_IN_RING_REF(page, idx) \
+	(XENFB_IN_RING((page))[(idx) % XENFB_IN_RING_LEN])
+
+#define XENFB_OUT_RING_SIZE 2048
+#define XENFB_OUT_RING_LEN (XENFB_OUT_RING_SIZE / XENFB_OUT_EVENT_SIZE)
+#define XENFB_OUT_RING_OFFS (XENFB_IN_RING_OFFS + XENFB_IN_RING_SIZE)
+#define XENFB_OUT_RING(page) \
+	((union xenfb_out_event *)((char *)(page) + XENFB_OUT_RING_OFFS))
+#define XENFB_OUT_RING_REF(page, idx) \
+	(XENFB_OUT_RING((page))[(idx) % XENFB_OUT_RING_LEN])
+
+struct xenfb_page {
+	uint32_t in_cons, in_prod;
+	uint32_t out_cons, out_prod;
+
+	int32_t width;          /* width of the framebuffer (in pixels) */
+	int32_t height;         /* height of the framebuffer (in pixels) */
+	uint32_t line_length;   /* length of a row of pixels (in bytes) */
+	uint32_t mem_length;    /* length of the framebuffer (in bytes) */
+	uint8_t depth;          /* depth of a pixel (in bits) */
+
+	/*
+	 * Framebuffer page directory
+	 *
+	 * Each directory page holds PAGE_SIZE / sizeof(*pd)
+	 * framebuffer pages, and can thus map up to PAGE_SIZE *
+	 * PAGE_SIZE / sizeof(*pd) bytes.  With PAGE_SIZE == 4096 and
+	 * sizeof(unsigned long) == 4, that's 4 Megs.  Two directory
+	 * pages should be enough for a while.
+	 */
+	unsigned long pd[2];
+};
+
+/*
+ * Wart: xenkbd needs to know resolution.  Put it here until a better
+ * solution is found, but don't leak it to the backend.
+ */
+#ifdef __KERNEL__
+#define XENFB_WIDTH 800
+#define XENFB_HEIGHT 600
+#define XENFB_DEPTH 32
+#endif
+
+#endif