drm: Add Allwinner A10 Display Engine support

The Allwinner A10 and subsequent SoCs share the same display pipeline, with
variations in the number of controllers (1 or 2), or the presence or not of
some output (HDMI, TV, VGA) or not.

Add a driver with a limited set of features for now, and we will hopefully
support all of them eventually

Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

1 files changed, 120 insertions, 0 deletions

diff --git a/drivers/gpu/drm/sun4i/sun4i_crtc.c b/drivers/gpu/drm/sun4i/sun4i_crtc.c
new file mode 100644
index 000000000000..4182a21f5923
--- /dev/null
+++ b/drivers/gpu/drm/sun4i/sun4i_crtc.c
@@ -0,0 +1,120 @@
+/*
+ * Copyright (C) 2015 Free Electrons
+ * Copyright (C) 2015 NextThing Co
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * 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 <drm/drmP.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_modes.h>
+
+#include <linux/clk-provider.h>
+#include <linux/ioport.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/regmap.h>
+
+#include <video/videomode.h>
+
+#include "sun4i_backend.h"
+#include "sun4i_crtc.h"
+#include "sun4i_drv.h"
+#include "sun4i_tcon.h"
+
+static void sun4i_crtc_atomic_begin(struct drm_crtc *crtc,
+				    struct drm_crtc_state *old_state)
+{
+	struct sun4i_crtc *scrtc = drm_crtc_to_sun4i_crtc(crtc);
+	struct drm_device *dev = crtc->dev;
+	unsigned long flags;
+
+	if (crtc->state->event) {
+		WARN_ON(drm_crtc_vblank_get(crtc) != 0);
+
+		spin_lock_irqsave(&dev->event_lock, flags);
+		scrtc->event = crtc->state->event;
+		spin_unlock_irqrestore(&dev->event_lock, flags);
+		crtc->state->event = NULL;
+	 }
+}
+
+static void sun4i_crtc_atomic_flush(struct drm_crtc *crtc,
+				    struct drm_crtc_state *old_state)
+{
+	struct sun4i_crtc *scrtc = drm_crtc_to_sun4i_crtc(crtc);
+	struct sun4i_drv *drv = scrtc->drv;
+
+	DRM_DEBUG_DRIVER("Committing plane changes\n");
+
+	sun4i_backend_commit(drv->backend);
+}
+
+static void sun4i_crtc_disable(struct drm_crtc *crtc)
+{
+	struct sun4i_crtc *scrtc = drm_crtc_to_sun4i_crtc(crtc);
+	struct sun4i_drv *drv = scrtc->drv;
+
+	DRM_DEBUG_DRIVER("Disabling the CRTC\n");
+
+	sun4i_tcon_disable(drv->tcon);
+}
+
+static void sun4i_crtc_enable(struct drm_crtc *crtc)
+{
+	struct sun4i_crtc *scrtc = drm_crtc_to_sun4i_crtc(crtc);
+	struct sun4i_drv *drv = scrtc->drv;
+
+	DRM_DEBUG_DRIVER("Enabling the CRTC\n");
+
+	sun4i_tcon_enable(drv->tcon);
+}
+
+static const struct drm_crtc_helper_funcs sun4i_crtc_helper_funcs = {
+	.atomic_begin	= sun4i_crtc_atomic_begin,
+	.atomic_flush	= sun4i_crtc_atomic_flush,
+	.disable	= sun4i_crtc_disable,
+	.enable		= sun4i_crtc_enable,
+};
+
+static const struct drm_crtc_funcs sun4i_crtc_funcs = {
+	.atomic_destroy_state	= drm_atomic_helper_crtc_destroy_state,
+	.atomic_duplicate_state	= drm_atomic_helper_crtc_duplicate_state,
+	.destroy		= drm_crtc_cleanup,
+	.page_flip		= drm_atomic_helper_page_flip,
+	.reset			= drm_atomic_helper_crtc_reset,
+	.set_config		= drm_atomic_helper_set_config,
+};
+
+struct sun4i_crtc *sun4i_crtc_init(struct drm_device *drm)
+{
+	struct sun4i_drv *drv = drm->dev_private;
+	struct sun4i_crtc *scrtc;
+	int ret;
+
+	scrtc = devm_kzalloc(drm->dev, sizeof(*scrtc), GFP_KERNEL);
+	if (!scrtc)
+		return NULL;
+	scrtc->drv = drv;
+
+	ret = drm_crtc_init_with_planes(drm, &scrtc->crtc,
+					drv->primary,
+					NULL,
+					&sun4i_crtc_funcs,
+					NULL);
+	if (ret) {
+		dev_err(drm->dev, "Couldn't init DRM CRTC\n");
+		return NULL;
+	}
+
+	drm_crtc_helper_add(&scrtc->crtc, &sun4i_crtc_helper_funcs);
+
+	return scrtc;
+}