1/* $NetBSD: tegra_drm_fb.c,v 1.10 2021/12/19 12:44:14 riastradh Exp $ */
2
3/*-
4 * Copyright (c) 2015 Jared D. McNeill <jmcneill@invisible.ca>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30__KERNEL_RCSID(0, "$NetBSD: tegra_drm_fb.c,v 1.10 2021/12/19 12:44:14 riastradh Exp $");
31
32#include <drm/drm_crtc.h>
33#include <drm/drm_crtc_helper.h>
34#include <drm/drm_drv.h>
35#include <drm/drm_fb_helper.h>
36#include <drm/drm_fourcc.h>
37
38#include <arm/nvidia/tegra_drm.h>
39
40static int	tegra_fb_init(struct drm_device *, struct drm_framebuffer *,
41		    struct drm_fb_helper_surface_size *);
42
43static int	tegra_fb_probe(struct drm_fb_helper *,
44		    struct drm_fb_helper_surface_size *);
45
46static struct drm_fb_helper_funcs tegra_fb_helper_funcs = {
47	.fb_probe = tegra_fb_probe
48};
49
50int
51tegra_drm_fb_init(struct drm_device *ddev)
52{
53	struct tegra_fbdev *fbdev;
54	int error;
55
56	fbdev = kmem_zalloc(sizeof(*fbdev), KM_SLEEP);
57
58	drm_fb_helper_prepare(ddev, &fbdev->helper, &tegra_fb_helper_funcs);
59
60	error = drm_fb_helper_init(ddev, &fbdev->helper, 1);
61	if (error) {
62		kmem_free(fbdev, sizeof(*fbdev));
63		return error;
64	}
65
66	/*
67	 * This might seem silly, but it saves us from having to allocate
68	 * enough memory for the largest possible framebuffer (around 35MB).
69	 *
70	 * Allocate the fb_helper's framebuffer here but don't initialize
71	 * it yet. The fb helper won't configure a CRTC unless this field is
72	 * set, and we don't know the preferred size at this time.
73	 *
74	 * The fb_probe callback will eventually be called with the preferred
75	 * surface size, so defer allocating the buffer object until then.
76	 */
77	fbdev->helper.fb =
78	    kmem_zalloc(sizeof(struct tegra_framebuffer), KM_SLEEP);
79
80	drm_fb_helper_single_add_all_connectors(&fbdev->helper);
81
82	drm_helper_disable_unused_functions(ddev);
83
84	drm_fb_helper_initial_config(&fbdev->helper, 32);
85
86	return 0;
87}
88
89static int
90tegra_fb_probe(struct drm_fb_helper *helper,
91    struct drm_fb_helper_surface_size *sizes)
92{
93	struct tegra_drm_softc * const sc = tegra_drm_private(helper->dev);
94	struct drm_device *ddev = helper->dev;
95	struct tegra_drmfb_attach_args tfa;
96
97	if (tegra_fb_init(ddev, helper->fb, sizes) != 0) {
98		DRM_ERROR("failed to initialize framebuffer\n");
99		return -ENOMEM;
100	}
101
102	memset(&tfa, 0, sizeof(tfa));
103	tfa.tfa_drm_dev = ddev;
104	tfa.tfa_fb_helper = helper;
105	tfa.tfa_fb_sizes = *sizes;
106	tfa.tfa_fb_bst = sc->sc_bst;
107	tfa.tfa_fb_dmat = sc->sc_dmat;
108	tfa.tfa_fb_linebytes = helper->fb->pitches[0];
109
110	helper->fbdev = config_found(ddev->dev, &tfa, NULL,
111	    CFARGS(.iattr = "tegrafbbus"));
112	if (helper->fbdev == NULL) {
113		DRM_ERROR("unable to attach tegrafb\n");
114		return -ENXIO;
115	}
116
117	return 0;
118}
119
120static int
121tegra_fb_init(struct drm_device *ddev, struct drm_framebuffer *fb,
122    struct drm_fb_helper_surface_size *sizes)
123{
124	struct tegra_framebuffer *tegra_fb = to_tegra_framebuffer(fb);
125	const u_int width = sizes->surface_width;
126	const u_int height = sizes->surface_height;
127	const u_int pitch = width * (32 / 8);
128
129	const size_t size = roundup(height * pitch, PAGE_SIZE);
130
131	tegra_fb->obj = drm_gem_cma_create(ddev, size);
132	if (tegra_fb->obj == NULL)
133		return -ENOMEM;
134
135	fb->pitches[0] = pitch;
136	fb->offsets[0] = 0;
137	fb->width = width;
138	fb->height = height;
139	fb->modifier = 0;
140	fb->flags = 0;
141	fb->format = drm_format_info(DRM_FORMAT_XRGB8888); /* XXX endian? */
142	fb->dev = ddev;
143	tegra_drm_framebuffer_init(ddev, tegra_fb);
144
145	return 0;
146}
147