drm/tegra: Hide fbdev support behind config option

Only build tegra's fbdev emulation if CONFIG_DRM_FBDEV_EMULATION
has been enabled. As part of this change, move the code into its
own source file. No functional changes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>

1 files changed, 227 insertions, 0 deletions

diff --git a/drivers/gpu/drm/tegra/fbdev.c b/drivers/gpu/drm/tegra/fbdev.c
new file mode 100644
index 000000000000..1c22d0fb4055
--- /dev/null
+++ b/drivers/gpu/drm/tegra/fbdev.c
@@ -0,0 +1,227 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2012-2013 Avionic Design GmbH
+ * Copyright (C) 2012 NVIDIA CORPORATION.  All rights reserved.
+ *
+ * Based on the KMS/FB DMA helpers
+ *   Copyright (C) 2012 Analog Devices Inc.
+ */
+
+#include <linux/console.h>
+#include <linux/vmalloc.h>
+
+#include <drm/drm_fourcc.h>
+#include <drm/drm_framebuffer.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_modeset_helper.h>
+
+#include "drm.h"
+#include "gem.h"
+
+static int tegra_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
+{
+	struct drm_fb_helper *helper = info->par;
+	struct tegra_bo *bo;
+	int err;
+
+	bo = tegra_fb_get_plane(helper->fb, 0);
+
+	err = drm_gem_mmap_obj(&bo->gem, bo->gem.size, vma);
+	if (err < 0)
+		return err;
+
+	return __tegra_gem_mmap(&bo->gem, vma);
+}
+
+static const struct fb_ops tegra_fb_ops = {
+	.owner = THIS_MODULE,
+	DRM_FB_HELPER_DEFAULT_OPS,
+	.fb_read = drm_fb_helper_sys_read,
+	.fb_write = drm_fb_helper_sys_write,
+	.fb_fillrect = drm_fb_helper_sys_fillrect,
+	.fb_copyarea = drm_fb_helper_sys_copyarea,
+	.fb_imageblit = drm_fb_helper_sys_imageblit,
+	.fb_mmap = tegra_fb_mmap,
+};
+
+static int tegra_fbdev_probe(struct drm_fb_helper *helper,
+			     struct drm_fb_helper_surface_size *sizes)
+{
+	struct tegra_drm *tegra = helper->dev->dev_private;
+	struct drm_device *drm = helper->dev;
+	struct drm_mode_fb_cmd2 cmd = { 0 };
+	unsigned int bytes_per_pixel;
+	struct drm_framebuffer *fb;
+	unsigned long offset;
+	struct fb_info *info;
+	struct tegra_bo *bo;
+	size_t size;
+	int err;
+
+	bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
+
+	cmd.width = sizes->surface_width;
+	cmd.height = sizes->surface_height;
+	cmd.pitches[0] = round_up(sizes->surface_width * bytes_per_pixel,
+				  tegra->pitch_align);
+
+	cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
+						     sizes->surface_depth);
+
+	size = cmd.pitches[0] * cmd.height;
+
+	bo = tegra_bo_create(drm, size, 0);
+	if (IS_ERR(bo))
+		return PTR_ERR(bo);
+
+	info = drm_fb_helper_alloc_info(helper);
+	if (IS_ERR(info)) {
+		dev_err(drm->dev, "failed to allocate framebuffer info\n");
+		drm_gem_object_put(&bo->gem);
+		return PTR_ERR(info);
+	}
+
+	fb = tegra_fb_alloc(drm, &cmd, &bo, 1);
+	if (IS_ERR(fb)) {
+		err = PTR_ERR(fb);
+		dev_err(drm->dev, "failed to allocate DRM framebuffer: %d\n",
+			err);
+		drm_gem_object_put(&bo->gem);
+		return PTR_ERR(fb);
+	}
+
+	helper->fb = fb;
+	helper->info = info;
+
+	info->fbops = &tegra_fb_ops;
+
+	drm_fb_helper_fill_info(info, helper, sizes);
+
+	offset = info->var.xoffset * bytes_per_pixel +
+		 info->var.yoffset * fb->pitches[0];
+
+	if (bo->pages) {
+		bo->vaddr = vmap(bo->pages, bo->num_pages, VM_MAP,
+				 pgprot_writecombine(PAGE_KERNEL));
+		if (!bo->vaddr) {
+			dev_err(drm->dev, "failed to vmap() framebuffer\n");
+			err = -ENOMEM;
+			goto destroy;
+		}
+	}
+
+	info->screen_base = (void __iomem *)bo->vaddr + offset;
+	info->screen_size = size;
+	info->fix.smem_start = (unsigned long)(bo->iova + offset);
+	info->fix.smem_len = size;
+
+	return 0;
+
+destroy:
+	drm_framebuffer_remove(fb);
+	return err;
+}
+
+static const struct drm_fb_helper_funcs tegra_fb_helper_funcs = {
+	.fb_probe = tegra_fbdev_probe,
+};
+
+static struct drm_fb_helper *tegra_fbdev_create(struct drm_device *drm)
+{
+	struct drm_fb_helper *helper;
+
+	helper = kzalloc(sizeof(*helper), GFP_KERNEL);
+	if (!helper)
+		return ERR_PTR(-ENOMEM);
+
+	drm_fb_helper_prepare(drm, helper, 32, &tegra_fb_helper_funcs);
+
+	return helper;
+}
+
+static void tegra_fbdev_free(struct drm_fb_helper *helper)
+{
+	drm_fb_helper_unprepare(helper);
+	kfree(helper);
+}
+
+static int tegra_fbdev_init(struct drm_fb_helper *helper,
+			    unsigned int num_crtc,
+			    unsigned int max_connectors)
+{
+	struct drm_device *drm = helper->dev;
+	int err;
+
+	err = drm_fb_helper_init(drm, helper);
+	if (err < 0) {
+		dev_err(drm->dev, "failed to initialize DRM FB helper: %d\n",
+			err);
+		return err;
+	}
+
+	err = drm_fb_helper_initial_config(helper);
+	if (err < 0) {
+		dev_err(drm->dev, "failed to set initial configuration: %d\n",
+			err);
+		goto fini;
+	}
+
+	return 0;
+
+fini:
+	drm_fb_helper_fini(helper);
+	return err;
+}
+
+static void tegra_fbdev_exit(struct drm_fb_helper *helper)
+{
+	struct drm_framebuffer *fb = helper->fb;
+
+	drm_fb_helper_unregister_info(helper);
+
+	if (fb) {
+		struct tegra_bo *bo = tegra_fb_get_plane(fb, 0);
+
+		/* Undo the special mapping we made in fbdev probe. */
+		if (bo && bo->pages) {
+			vunmap(bo->vaddr);
+			bo->vaddr = NULL;
+		}
+
+		drm_framebuffer_remove(fb);
+	}
+
+	drm_fb_helper_fini(helper);
+	tegra_fbdev_free(helper);
+}
+
+int tegra_drm_fb_prepare(struct drm_device *drm)
+{
+	drm->fb_helper = tegra_fbdev_create(drm);
+	if (IS_ERR(drm->fb_helper))
+		return PTR_ERR(drm->fb_helper);
+
+	return 0;
+}
+
+void tegra_drm_fb_free(struct drm_device *drm)
+{
+	tegra_fbdev_free(drm->fb_helper);
+}
+
+int tegra_drm_fb_init(struct drm_device *drm)
+{
+	int err;
+
+	err = tegra_fbdev_init(drm->fb_helper, drm->mode_config.num_crtc,
+			       drm->mode_config.num_connector);
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+
+void tegra_drm_fb_exit(struct drm_device *drm)
+{
+	tegra_fbdev_exit(drm->fb_helper);
+}