msm_fbdev.c

  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}
 56
 57static const struct fb_ops msm_fb_ops = {
 58	.owner = THIS_MODULE,
 59	__FB_DEFAULT_DEFERRED_OPS_RDWR(msm_fbdev),
 60	DRM_FB_HELPER_DEFAULT_OPS,
 61	__FB_DEFAULT_DEFERRED_OPS_DRAW(msm_fbdev),
 62	.fb_mmap = msm_fbdev_mmap,
 63	.fb_destroy = msm_fbdev_fb_destroy,
 64};
 65
 66static int msm_fbdev_fb_dirty(struct drm_fb_helper *helper,
 67			      struct drm_clip_rect *clip)
 68{
 69	struct drm_device *dev = helper->dev;
 70	int ret;
 71
 72	/* Call damage handlers only if necessary */
 73	if (!(clip->x1 < clip->x2 && clip->y1 < clip->y2))
 74		return 0;
 75
 76	if (helper->fb->funcs->dirty) {
 77		ret = helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, clip, 1);
 78		if (drm_WARN_ONCE(dev, ret, "Dirty helper failed: ret=%d\n", ret))
 79			return ret;
 80	}
 81
 82	return 0;
 83}
 84
 85static const struct drm_fb_helper_funcs msm_fbdev_helper_funcs = {
 86	.fb_dirty = msm_fbdev_fb_dirty,
 87};
 88
 89int msm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 90				 struct drm_fb_helper_surface_size *sizes)
 91{
 92	struct drm_device *dev = helper->dev;
 93	struct msm_drm_private *priv = dev->dev_private;
 94	struct fb_info *fbi = helper->info;
 95	struct drm_framebuffer *fb = NULL;
 96	struct drm_gem_object *bo;
 97	uint64_t paddr;
 98	uint32_t format;
 99	int ret, pitch;
100
101	format = drm_mode_legacy_fb_format(sizes->surface_bpp, sizes->surface_depth);
102
103	DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
104			sizes->surface_height, sizes->surface_bpp,
105			sizes->fb_width, sizes->fb_height);
106
107	pitch = align_pitch(sizes->surface_width, sizes->surface_bpp);
108	fb = msm_alloc_stolen_fb(dev, sizes->surface_width,
109			sizes->surface_height, pitch, format);
110
111	if (IS_ERR(fb)) {
112		DRM_DEV_ERROR(dev->dev, "failed to allocate fb\n");
113		return PTR_ERR(fb);
114	}
115
116	bo = msm_framebuffer_bo(fb, 0);
117
118	/*
119	 * NOTE: if we can be guaranteed to be able to map buffer
120	 * in panic (ie. lock-safe, etc) we could avoid pinning the
121	 * buffer now:
122	 */
123	ret = msm_gem_get_and_pin_iova(bo, priv->kms->vm, &paddr);
124	if (ret) {
125		DRM_DEV_ERROR(dev->dev, "failed to get buffer obj iova: %d\n", ret);
126		goto fail;
127	}
128
129	DBG("fbi=%p, dev=%p", fbi, dev);
130
131	helper->funcs = &msm_fbdev_helper_funcs;
132	helper->fb = fb;
133
134	fbi->fbops = &msm_fb_ops;
135
136	drm_fb_helper_fill_info(fbi, helper, sizes);
137
138	fbi->screen_buffer = msm_gem_get_vaddr(bo);
139	if (IS_ERR(fbi->screen_buffer)) {
140		ret = PTR_ERR(fbi->screen_buffer);
141		goto fail;
142	}
143	fbi->screen_size = bo->size;
144	fbi->fix.smem_start = paddr;
145	fbi->fix.smem_len = bo->size;
146
147	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
148	DBG("allocated %dx%d fb", fb->width, fb->height);
149
150	return 0;
151
152fail:
153	drm_framebuffer_remove(fb);
154	return ret;
155}