1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2013 Red Hat
  4 * Author: Rob Clark <robdclark@gmail.com>
  5 */
  6
  7#include <linux/fb.h>
  8
  9#include <drm/drm_drv.h>
 10#include <drm/drm_crtc_helper.h>
 11#include <drm/drm_fb_helper.h>
 12#include <drm/drm_fourcc.h>
 13#include <drm/drm_framebuffer.h>
 14#include <drm/drm_prime.h>
 15
 16#include "msm_drv.h"
 17#include "msm_gem.h"
 18#include "msm_kms.h"
 19
 20static bool fbdev = true;
 21MODULE_PARM_DESC(fbdev, "Enable fbdev compat layer");
 22module_param(fbdev, bool, 0600);
 23
 24/*
 25 * fbdev funcs, to implement legacy fbdev interface on top of drm driver
 26 */
 27
 28FB_GEN_DEFAULT_DEFERRED_SYSMEM_OPS(msm_fbdev,
 29				   drm_fb_helper_damage_range,
 30				   drm_fb_helper_damage_area)
 31
 32static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma)
 33{
 34	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
 35	struct drm_gem_object *bo = msm_framebuffer_bo(helper->fb, 0);
 36
 37	return drm_gem_prime_mmap(bo, vma);
 38}
 39
 40static void msm_fbdev_fb_destroy(struct fb_info *info)
 41{
 42	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
 43	struct drm_framebuffer *fb = helper->fb;
 44	struct drm_gem_object *bo = msm_framebuffer_bo(fb, 0);
 45
 46	DBG();
 47
 48	drm_fb_helper_fini(helper);
 49
 50	/* this will free the backing object */
 51	msm_gem_put_vaddr(bo);
 52	drm_framebuffer_remove(fb);
 53
 54	drm_client_release(&helper->client);
 55	drm_fb_helper_unprepare(helper);
 56	kfree(helper);
 57}
 58
 59static const struct fb_ops msm_fb_ops = {
 60	.owner = THIS_MODULE,
 61	__FB_DEFAULT_DEFERRED_OPS_RDWR(msm_fbdev),
 62	DRM_FB_HELPER_DEFAULT_OPS,
 63	__FB_DEFAULT_DEFERRED_OPS_DRAW(msm_fbdev),
 64	.fb_mmap = msm_fbdev_mmap,
 65	.fb_destroy = msm_fbdev_fb_destroy,
 66};
 67
 68static int msm_fbdev_fb_dirty(struct drm_fb_helper *helper,
 69			      struct drm_clip_rect *clip)
 70{
 71	struct drm_device *dev = helper->dev;
 72	int ret;
 73
 74	/* Call damage handlers only if necessary */
 75	if (!(clip->x1 < clip->x2 && clip->y1 < clip->y2))
 76		return 0;
 77
 78	if (helper->fb->funcs->dirty) {
 79		ret = helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, clip, 1);
 80		if (drm_WARN_ONCE(dev, ret, "Dirty helper failed: ret=%d\n", ret))
 81			return ret;
 82	}
 83
 84	return 0;
 85}
 86
 87static const struct drm_fb_helper_funcs msm_fbdev_helper_funcs = {
 88	.fb_dirty = msm_fbdev_fb_dirty,
 89};
 90
 91int msm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 92				 struct drm_fb_helper_surface_size *sizes)
 93{
 94	struct drm_device *dev = helper->dev;
 95	struct msm_drm_private *priv = dev->dev_private;
 96	struct drm_framebuffer *fb = NULL;
 97	struct drm_gem_object *bo;
 98	struct fb_info *fbi = NULL;
 99	uint64_t paddr;
100	uint32_t format;
101	int ret, pitch;
102
103	format = drm_mode_legacy_fb_format(sizes->surface_bpp, sizes->surface_depth);
104
105	DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
106			sizes->surface_height, sizes->surface_bpp,
107			sizes->fb_width, sizes->fb_height);
108
109	pitch = align_pitch(sizes->surface_width, sizes->surface_bpp);
110	fb = msm_alloc_stolen_fb(dev, sizes->surface_width,
111			sizes->surface_height, pitch, format);
112
113	if (IS_ERR(fb)) {
114		DRM_DEV_ERROR(dev->dev, "failed to allocate fb\n");
115		return PTR_ERR(fb);
116	}
117
118	bo = msm_framebuffer_bo(fb, 0);
119
120	/*
121	 * NOTE: if we can be guaranteed to be able to map buffer
122	 * in panic (ie. lock-safe, etc) we could avoid pinning the
123	 * buffer now:
124	 */
125	ret = msm_gem_get_and_pin_iova(bo, priv->kms->aspace, &paddr);
126	if (ret) {
127		DRM_DEV_ERROR(dev->dev, "failed to get buffer obj iova: %d\n", ret);
128		goto fail;
129	}
130
131	fbi = drm_fb_helper_alloc_info(helper);
132	if (IS_ERR(fbi)) {
133		DRM_DEV_ERROR(dev->dev, "failed to allocate fb info\n");
134		ret = PTR_ERR(fbi);
135		goto fail;
136	}
137
138	DBG("fbi=%p, dev=%p", fbi, dev);
139
140	helper->funcs = &msm_fbdev_helper_funcs;
141	helper->fb = fb;
142
143	fbi->fbops = &msm_fb_ops;
144
145	drm_fb_helper_fill_info(fbi, helper, sizes);
146
147	fbi->screen_buffer = msm_gem_get_vaddr(bo);
148	if (IS_ERR(fbi->screen_buffer)) {
149		ret = PTR_ERR(fbi->screen_buffer);
150		goto fail;
151	}
152	fbi->screen_size = bo->size;
153	fbi->fix.smem_start = paddr;
154	fbi->fix.smem_len = bo->size;
155
156	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
157	DBG("allocated %dx%d fb", fb->width, fb->height);
158
159	return 0;
160
161fail:
162	drm_framebuffer_remove(fb);
163	return ret;
164}