DRM: Armada: Add Armada DRM driver

This patch adds support for the pair of LCD controllers on the Marvell
Armada 510 SoCs.  This driver supports:
- multiple contiguous scanout buffers for video and graphics
- shm backed cacheable buffer objects for X pixmaps for Vivante GPU
  acceleration
- dual lcd0 and lcd1 crt operation
- video overlay on each LCD crt via DRM planes
- page flipping of the main scanout buffers
- DRM prime for buffer export/import

This driver is trivial to extend to other Armada SoCs.

Included in this commit is the core driver with no output support; output
support is platform and encoder driver dependent.

Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 202 insertions, 0 deletions

diff --git a/drivers/gpu/drm/armada/armada_fbdev.c b/drivers/gpu/drm/armada/armada_fbdev.c
new file mode 100644
index 000000000000..dd5ea77dac96
--- /dev/null
+++ b/drivers/gpu/drm/armada/armada_fbdev.c
@@ -0,0 +1,202 @@
+/*
+ * Copyright (C) 2012 Russell King
+ *  Written from the i915 driver.
+ *
+ * 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/errno.h>
+#include <linux/fb.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include <drm/drmP.h>
+#include <drm/drm_fb_helper.h>
+#include "armada_crtc.h"
+#include "armada_drm.h"
+#include "armada_fb.h"
+#include "armada_gem.h"
+
+static /*const*/ struct fb_ops armada_fb_ops = {
+	.owner		= THIS_MODULE,
+	.fb_check_var	= drm_fb_helper_check_var,
+	.fb_set_par	= drm_fb_helper_set_par,
+	.fb_fillrect	= cfb_fillrect,
+	.fb_copyarea	= cfb_copyarea,
+	.fb_imageblit	= cfb_imageblit,
+	.fb_pan_display	= drm_fb_helper_pan_display,
+	.fb_blank	= drm_fb_helper_blank,
+	.fb_setcmap	= drm_fb_helper_setcmap,
+	.fb_debug_enter	= drm_fb_helper_debug_enter,
+	.fb_debug_leave	= drm_fb_helper_debug_leave,
+};
+
+static int armada_fb_create(struct drm_fb_helper *fbh,
+	struct drm_fb_helper_surface_size *sizes)
+{
+	struct drm_device *dev = fbh->dev;
+	struct drm_mode_fb_cmd2 mode;
+	struct armada_framebuffer *dfb;
+	struct armada_gem_object *obj;
+	struct fb_info *info;
+	int size, ret;
+	void *ptr;
+
+	memset(&mode, 0, sizeof(mode));
+	mode.width = sizes->surface_width;
+	mode.height = sizes->surface_height;
+	mode.pitches[0] = armada_pitch(mode.width, sizes->surface_bpp);
+	mode.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
+					sizes->surface_depth);
+
+	size = mode.pitches[0] * mode.height;
+	obj = armada_gem_alloc_private_object(dev, size);
+	if (!obj) {
+		DRM_ERROR("failed to allocate fb memory\n");
+		return -ENOMEM;
+	}
+
+	ret = armada_gem_linear_back(dev, obj);
+	if (ret) {
+		drm_gem_object_unreference_unlocked(&obj->obj);
+		return ret;
+	}
+
+	ptr = armada_gem_map_object(dev, obj);
+	if (!ptr) {
+		drm_gem_object_unreference_unlocked(&obj->obj);
+		return -ENOMEM;
+	}
+
+	dfb = armada_framebuffer_create(dev, &mode, obj);
+
+	/*
+	 * A reference is now held by the framebuffer object if
+	 * successful, otherwise this drops the ref for the error path.
+	 */
+	drm_gem_object_unreference_unlocked(&obj->obj);
+
+	if (IS_ERR(dfb))
+		return PTR_ERR(dfb);
+
+	info = framebuffer_alloc(0, dev->dev);
+	if (!info) {
+		ret = -ENOMEM;
+		goto err_fballoc;
+	}
+
+	ret = fb_alloc_cmap(&info->cmap, 256, 0);
+	if (ret) {
+		ret = -ENOMEM;
+		goto err_fbcmap;
+	}
+
+	strlcpy(info->fix.id, "armada-drmfb", sizeof(info->fix.id));
+	info->par = fbh;
+	info->flags = FBINFO_DEFAULT | FBINFO_CAN_FORCE_OUTPUT;
+	info->fbops = &armada_fb_ops;
+	info->fix.smem_start = obj->phys_addr;
+	info->fix.smem_len = obj->obj.size;
+	info->screen_size = obj->obj.size;
+	info->screen_base = ptr;
+	fbh->fb = &dfb->fb;
+	fbh->fbdev = info;
+	drm_fb_helper_fill_fix(info, dfb->fb.pitches[0], dfb->fb.depth);
+	drm_fb_helper_fill_var(info, fbh, sizes->fb_width, sizes->fb_height);
+
+	DRM_DEBUG_KMS("allocated %dx%d %dbpp fb: 0x%08x\n",
+		dfb->fb.width, dfb->fb.height,
+		dfb->fb.bits_per_pixel, obj->phys_addr);
+
+	return 0;
+
+ err_fbcmap:
+	framebuffer_release(info);
+ err_fballoc:
+	dfb->fb.funcs->destroy(&dfb->fb);
+	return ret;
+}
+
+static int armada_fb_probe(struct drm_fb_helper *fbh,
+	struct drm_fb_helper_surface_size *sizes)
+{
+	int ret = 0;
+
+	if (!fbh->fb) {
+		ret = armada_fb_create(fbh, sizes);
+		if (ret == 0)
+			ret = 1;
+	}
+	return ret;
+}
+
+static struct drm_fb_helper_funcs armada_fb_helper_funcs = {
+	.gamma_set	= armada_drm_crtc_gamma_set,
+	.gamma_get	= armada_drm_crtc_gamma_get,
+	.fb_probe	= armada_fb_probe,
+};
+
+int armada_fbdev_init(struct drm_device *dev)
+{
+	struct armada_private *priv = dev->dev_private;
+	struct drm_fb_helper *fbh;
+	int ret;
+
+	fbh = devm_kzalloc(dev->dev, sizeof(*fbh), GFP_KERNEL);
+	if (!fbh)
+		return -ENOMEM;
+
+	priv->fbdev = fbh;
+
+	fbh->funcs = &armada_fb_helper_funcs;
+
+	ret = drm_fb_helper_init(dev, fbh, 1, 1);
+	if (ret) {
+		DRM_ERROR("failed to initialize drm fb helper\n");
+		goto err_fb_helper;
+	}
+
+	ret = drm_fb_helper_single_add_all_connectors(fbh);
+	if (ret) {
+		DRM_ERROR("failed to add fb connectors\n");
+		goto err_fb_setup;
+	}
+
+	ret = drm_fb_helper_initial_config(fbh, 32);
+	if (ret) {
+		DRM_ERROR("failed to set initial config\n");
+		goto err_fb_setup;
+	}
+
+	return 0;
+ err_fb_setup:
+	drm_fb_helper_fini(fbh);
+ err_fb_helper:
+	priv->fbdev = NULL;
+	return ret;
+}
+
+void armada_fbdev_fini(struct drm_device *dev)
+{
+	struct armada_private *priv = dev->dev_private;
+	struct drm_fb_helper *fbh = priv->fbdev;
+
+	if (fbh) {
+		struct fb_info *info = fbh->fbdev;
+
+		if (info) {
+			unregister_framebuffer(info);
+			if (info->cmap.len)
+				fb_dealloc_cmap(&info->cmap);
+			framebuffer_release(info);
+		}
+
+		if (fbh->fb)
+			fbh->fb->funcs->destroy(fbh->fb);
+
+		drm_fb_helper_fini(fbh);
+
+		priv->fbdev = NULL;
+	}
+}