drm/vc4: Add KMS support for Raspberry Pi.

This is enough for fbcon and bringing up X using
xf86-video-modesetting.  It doesn't support the 3D accelerator or
power management yet.

v2: Drop FB_HELPER select thanks to Archit's patches.  Do manual init
    ordering instead of using the .load hook.  Structure registration
    more like tegra's, but still using the typical "component" code.
    Drop no-op hooks for atomic_begin and mode_fixup() now that
    they're optional.  Drop sentinel in Makefile.  Fix minor style
    nits I noticed on another reread.

v3: Use the new bcm2835 clk driver to manage pixel/HSM clocks instead
    of having a fixed video mode.  Use exynos-style component driver
    matching instead of devicetree nodes to list the component driver
    instances.  Rename compatibility strings to say bcm2835, and
    distinguish pv0/1/2.  Clean up some h/vsync code, and add in
    interlaced mode setup.  Fix up probe/bind error paths.  Use
    bitops.h macros for vc4_regs.h

v4: Include i2c.h, allow building under COMPILE_TEST, drop msleep now
    that other bugs have been fixed, add timeouts to cpu_relax()
    loops, rename hpd-gpio to hpd-gpios.

Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/vc4/vc4_debugfs.c b/drivers/gpu/drm/vc4/vc4_debugfs.c
new file mode 100644
index 0000000..4297b0a5
--- /dev/null
+++ b/drivers/gpu/drm/vc4/vc4_debugfs.c
@@ -0,0 +1,39 @@
+/*
+ *  Copyright © 2014 Broadcom
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/seq_file.h>
+#include <linux/circ_buf.h>
+#include <linux/ctype.h>
+#include <linux/debugfs.h>
+#include <drm/drmP.h>
+
+#include "vc4_drv.h"
+#include "vc4_regs.h"
+
+static const struct drm_info_list vc4_debugfs_list[] = {
+	{"hdmi_regs", vc4_hdmi_debugfs_regs, 0},
+	{"hvs_regs", vc4_hvs_debugfs_regs, 0},
+	{"crtc0_regs", vc4_crtc_debugfs_regs, 0, (void *)(uintptr_t)0},
+	{"crtc1_regs", vc4_crtc_debugfs_regs, 0, (void *)(uintptr_t)1},
+	{"crtc2_regs", vc4_crtc_debugfs_regs, 0, (void *)(uintptr_t)2},
+};
+
+#define VC4_DEBUGFS_ENTRIES ARRAY_SIZE(vc4_debugfs_list)
+
+int
+vc4_debugfs_init(struct drm_minor *minor)
+{
+	return drm_debugfs_create_files(vc4_debugfs_list, VC4_DEBUGFS_ENTRIES,
+					minor->debugfs_root, minor);
+}
+
+void
+vc4_debugfs_cleanup(struct drm_minor *minor)
+{
+	drm_debugfs_remove_files(vc4_debugfs_list, VC4_DEBUGFS_ENTRIES, minor);
+}