cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

omap_fbdev.c (7142B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Copyright (C) 2011 Texas Instruments Incorporated - https://www.ti.com/
      4 * Author: Rob Clark <rob@ti.com>
      5 */
      6
      7#include <drm/drm_crtc.h>
      8#include <drm/drm_util.h>
      9#include <drm/drm_fb_helper.h>
     10#include <drm/drm_file.h>
     11#include <drm/drm_fourcc.h>
     12
     13#include "omap_drv.h"
     14
     15MODULE_PARM_DESC(ywrap, "Enable ywrap scrolling (omap44xx and later, default 'y')");
     16static bool ywrap_enabled = true;
     17module_param_named(ywrap, ywrap_enabled, bool, 0644);
     18
     19/*
     20 * fbdev funcs, to implement legacy fbdev interface on top of drm driver
     21 */
     22
     23#define to_omap_fbdev(x) container_of(x, struct omap_fbdev, base)
     24
     25struct omap_fbdev {
     26	struct drm_fb_helper base;
     27	struct drm_framebuffer *fb;
     28	struct drm_gem_object *bo;
     29	bool ywrap_enabled;
     30
     31	/* for deferred dmm roll when getting called in atomic ctx */
     32	struct work_struct work;
     33};
     34
     35static struct drm_fb_helper *get_fb(struct fb_info *fbi);
     36
     37static void pan_worker(struct work_struct *work)
     38{
     39	struct omap_fbdev *fbdev = container_of(work, struct omap_fbdev, work);
     40	struct fb_info *fbi = fbdev->base.fbdev;
     41	int npages;
     42
     43	/* DMM roll shifts in 4K pages: */
     44	npages = fbi->fix.line_length >> PAGE_SHIFT;
     45	omap_gem_roll(fbdev->bo, fbi->var.yoffset * npages);
     46}
     47
     48static int omap_fbdev_pan_display(struct fb_var_screeninfo *var,
     49		struct fb_info *fbi)
     50{
     51	struct drm_fb_helper *helper = get_fb(fbi);
     52	struct omap_fbdev *fbdev = to_omap_fbdev(helper);
     53
     54	if (!helper)
     55		goto fallback;
     56
     57	if (!fbdev->ywrap_enabled)
     58		goto fallback;
     59
     60	if (drm_can_sleep()) {
     61		pan_worker(&fbdev->work);
     62	} else {
     63		struct omap_drm_private *priv = helper->dev->dev_private;
     64		queue_work(priv->wq, &fbdev->work);
     65	}
     66
     67	return 0;
     68
     69fallback:
     70	return drm_fb_helper_pan_display(var, fbi);
     71}
     72
     73static const struct fb_ops omap_fb_ops = {
     74	.owner = THIS_MODULE,
     75
     76	.fb_check_var	= drm_fb_helper_check_var,
     77	.fb_set_par	= drm_fb_helper_set_par,
     78	.fb_setcmap	= drm_fb_helper_setcmap,
     79	.fb_blank	= drm_fb_helper_blank,
     80	.fb_pan_display = omap_fbdev_pan_display,
     81	.fb_ioctl	= drm_fb_helper_ioctl,
     82
     83	.fb_read = drm_fb_helper_sys_read,
     84	.fb_write = drm_fb_helper_sys_write,
     85	.fb_fillrect = drm_fb_helper_sys_fillrect,
     86	.fb_copyarea = drm_fb_helper_sys_copyarea,
     87	.fb_imageblit = drm_fb_helper_sys_imageblit,
     88};
     89
     90static int omap_fbdev_create(struct drm_fb_helper *helper,
     91		struct drm_fb_helper_surface_size *sizes)
     92{
     93	struct omap_fbdev *fbdev = to_omap_fbdev(helper);
     94	struct drm_device *dev = helper->dev;
     95	struct omap_drm_private *priv = dev->dev_private;
     96	struct drm_framebuffer *fb = NULL;
     97	union omap_gem_size gsize;
     98	struct fb_info *fbi = NULL;
     99	struct drm_mode_fb_cmd2 mode_cmd = {0};
    100	dma_addr_t dma_addr;
    101	int ret;
    102
    103	sizes->surface_bpp = 32;
    104	sizes->surface_depth = 24;
    105
    106	DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
    107			sizes->surface_height, sizes->surface_bpp,
    108			sizes->fb_width, sizes->fb_height);
    109
    110	mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
    111			sizes->surface_depth);
    112
    113	mode_cmd.width = sizes->surface_width;
    114	mode_cmd.height = sizes->surface_height;
    115
    116	mode_cmd.pitches[0] =
    117			DIV_ROUND_UP(mode_cmd.width * sizes->surface_bpp, 8);
    118
    119	fbdev->ywrap_enabled = priv->has_dmm && ywrap_enabled;
    120	if (fbdev->ywrap_enabled) {
    121		/* need to align pitch to page size if using DMM scrolling */
    122		mode_cmd.pitches[0] = PAGE_ALIGN(mode_cmd.pitches[0]);
    123	}
    124
    125	/* allocate backing bo */
    126	gsize = (union omap_gem_size){
    127		.bytes = PAGE_ALIGN(mode_cmd.pitches[0] * mode_cmd.height),
    128	};
    129	DBG("allocating %d bytes for fb %d", gsize.bytes, dev->primary->index);
    130	fbdev->bo = omap_gem_new(dev, gsize, OMAP_BO_SCANOUT | OMAP_BO_WC);
    131	if (!fbdev->bo) {
    132		dev_err(dev->dev, "failed to allocate buffer object\n");
    133		ret = -ENOMEM;
    134		goto fail;
    135	}
    136
    137	fb = omap_framebuffer_init(dev, &mode_cmd, &fbdev->bo);
    138	if (IS_ERR(fb)) {
    139		dev_err(dev->dev, "failed to allocate fb\n");
    140		/* note: if fb creation failed, we can't rely on fb destroy
    141		 * to unref the bo:
    142		 */
    143		drm_gem_object_put(fbdev->bo);
    144		ret = PTR_ERR(fb);
    145		goto fail;
    146	}
    147
    148	/* note: this keeps the bo pinned.. which is perhaps not ideal,
    149	 * but is needed as long as we use fb_mmap() to mmap to userspace
    150	 * (since this happens using fix.smem_start).  Possibly we could
    151	 * implement our own mmap using GEM mmap support to avoid this
    152	 * (non-tiled buffer doesn't need to be pinned for fbcon to write
    153	 * to it).  Then we just need to be sure that we are able to re-
    154	 * pin it in case of an opps.
    155	 */
    156	ret = omap_gem_pin(fbdev->bo, &dma_addr);
    157	if (ret) {
    158		dev_err(dev->dev, "could not pin framebuffer\n");
    159		ret = -ENOMEM;
    160		goto fail;
    161	}
    162
    163	fbi = drm_fb_helper_alloc_fbi(helper);
    164	if (IS_ERR(fbi)) {
    165		dev_err(dev->dev, "failed to allocate fb info\n");
    166		ret = PTR_ERR(fbi);
    167		goto fail;
    168	}
    169
    170	DBG("fbi=%p, dev=%p", fbi, dev);
    171
    172	fbdev->fb = fb;
    173	helper->fb = fb;
    174
    175	fbi->fbops = &omap_fb_ops;
    176
    177	drm_fb_helper_fill_info(fbi, helper, sizes);
    178
    179	dev->mode_config.fb_base = dma_addr;
    180
    181	fbi->screen_buffer = omap_gem_vaddr(fbdev->bo);
    182	fbi->screen_size = fbdev->bo->size;
    183	fbi->fix.smem_start = dma_addr;
    184	fbi->fix.smem_len = fbdev->bo->size;
    185
    186	/* if we have DMM, then we can use it for scrolling by just
    187	 * shuffling pages around in DMM rather than doing sw blit.
    188	 */
    189	if (fbdev->ywrap_enabled) {
    190		DRM_INFO("Enabling DMM ywrap scrolling\n");
    191		fbi->flags |= FBINFO_HWACCEL_YWRAP | FBINFO_READS_FAST;
    192		fbi->fix.ywrapstep = 1;
    193	}
    194
    195
    196	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
    197	DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);
    198
    199	return 0;
    200
    201fail:
    202
    203	if (ret) {
    204		if (fb)
    205			drm_framebuffer_remove(fb);
    206	}
    207
    208	return ret;
    209}
    210
    211static const struct drm_fb_helper_funcs omap_fb_helper_funcs = {
    212	.fb_probe = omap_fbdev_create,
    213};
    214
    215static struct drm_fb_helper *get_fb(struct fb_info *fbi)
    216{
    217	if (!fbi || strcmp(fbi->fix.id, MODULE_NAME)) {
    218		/* these are not the fb's you're looking for */
    219		return NULL;
    220	}
    221	return fbi->par;
    222}
    223
    224/* initialize fbdev helper */
    225void omap_fbdev_init(struct drm_device *dev)
    226{
    227	struct omap_drm_private *priv = dev->dev_private;
    228	struct omap_fbdev *fbdev = NULL;
    229	struct drm_fb_helper *helper;
    230	int ret = 0;
    231
    232	if (!priv->num_pipes)
    233		return;
    234
    235	fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
    236	if (!fbdev)
    237		goto fail;
    238
    239	INIT_WORK(&fbdev->work, pan_worker);
    240
    241	helper = &fbdev->base;
    242
    243	drm_fb_helper_prepare(dev, helper, &omap_fb_helper_funcs);
    244
    245	ret = drm_fb_helper_init(dev, helper);
    246	if (ret)
    247		goto fail;
    248
    249	ret = drm_fb_helper_initial_config(helper, 32);
    250	if (ret)
    251		goto fini;
    252
    253	priv->fbdev = helper;
    254
    255	return;
    256
    257fini:
    258	drm_fb_helper_fini(helper);
    259fail:
    260	kfree(fbdev);
    261
    262	dev_warn(dev->dev, "omap_fbdev_init failed\n");
    263}
    264
    265void omap_fbdev_fini(struct drm_device *dev)
    266{
    267	struct omap_drm_private *priv = dev->dev_private;
    268	struct drm_fb_helper *helper = priv->fbdev;
    269	struct omap_fbdev *fbdev;
    270
    271	DBG();
    272
    273	if (!helper)
    274		return;
    275
    276	drm_fb_helper_unregister_fbi(helper);
    277
    278	drm_fb_helper_fini(helper);
    279
    280	fbdev = to_omap_fbdev(helper);
    281
    282	/* unpin the GEM object pinned in omap_fbdev_create() */
    283	if (fbdev->bo)
    284		omap_gem_unpin(fbdev->bo);
    285
    286	/* this will free the backing object */
    287	if (fbdev->fb)
    288		drm_framebuffer_remove(fbdev->fb);
    289
    290	kfree(fbdev);
    291
    292	priv->fbdev = NULL;
    293}