[mirror_ubuntu-hirsute-kernel.git] / samples / vfio-mdev / mdpy-fb.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Framebuffer driver for mdpy (mediated virtual pci display device).
 *
 * See mdpy-defs.h for device specs
 *
 *   (c) Gerd Hoffmann <kraxel@redhat.com>
 *
 * Using some code snippets from simplefb and cirrusfb.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 */
#include <linux/errno.h>
#include <linux/fb.h>
#include <linux/io.h>
#include <linux/pci.h>
#include <linux/module.h>
#include <drm/drm_fourcc.h>
#include "mdpy-defs.h"

static const struct fb_fix_screeninfo mdpy_fb_fix = {
	.id		= "mdpy-fb",
	.type		= FB_TYPE_PACKED_PIXELS,
	.visual		= FB_VISUAL_TRUECOLOR,
	.accel		= FB_ACCEL_NONE,
};

static const struct fb_var_screeninfo mdpy_fb_var = {
	.height		= -1,
	.width		= -1,
	.activate	= FB_ACTIVATE_NOW,
	.vmode		= FB_VMODE_NONINTERLACED,

	.bits_per_pixel = 32,
	.transp.offset	= 24,
	.red.offset	= 16,
	.green.offset	= 8,
	.blue.offset	= 0,
	.transp.length	= 8,
	.red.length	= 8,
	.green.length	= 8,
	.blue.length	= 8,
};

#define PSEUDO_PALETTE_SIZE 16

struct mdpy_fb_par {
	u32 palette[PSEUDO_PALETTE_SIZE];
};

static int mdpy_fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
			      u_int transp, struct fb_info *info)
{
	u32 *pal = info->pseudo_palette;
	u32 cr = red >> (16 - info->var.red.length);
	u32 cg = green >> (16 - info->var.green.length);
	u32 cb = blue >> (16 - info->var.blue.length);
	u32 value, mask;

	if (regno >= PSEUDO_PALETTE_SIZE)
		return -EINVAL;

	value = (cr << info->var.red.offset) |
		(cg << info->var.green.offset) |
		(cb << info->var.blue.offset);
	if (info->var.transp.length > 0) {
		mask = (1 << info->var.transp.length) - 1;
		mask <<= info->var.transp.offset;
		value |= mask;
	}
	pal[regno] = value;

	return 0;
}

static void mdpy_fb_destroy(struct fb_info *info)
{
	if (info->screen_base)
		iounmap(info->screen_base);
}

static const struct fb_ops mdpy_fb_ops = {
	.owner		= THIS_MODULE,
	.fb_destroy	= mdpy_fb_destroy,
	.fb_setcolreg	= mdpy_fb_setcolreg,
	.fb_fillrect	= cfb_fillrect,
	.fb_copyarea	= cfb_copyarea,
	.fb_imageblit	= cfb_imageblit,
};

static int mdpy_fb_probe(struct pci_dev *pdev,
			 const struct pci_device_id *ent)
{
	struct fb_info *info;
	struct mdpy_fb_par *par;
	u32 format, width, height;
	int ret;

	ret = pci_enable_device(pdev);
	if (ret < 0)
		return ret;

	ret = pci_request_regions(pdev, "mdpy-fb");
	if (ret < 0)
		return ret;

	pci_read_config_dword(pdev, MDPY_FORMAT_OFFSET, &format);
	pci_read_config_dword(pdev, MDPY_WIDTH_OFFSET,	&width);
	pci_read_config_dword(pdev, MDPY_HEIGHT_OFFSET, &height);
	if (format != DRM_FORMAT_XRGB8888) {
		pci_err(pdev, "format mismatch (0x%x != 0x%x)\n",
			format, DRM_FORMAT_XRGB8888);
		return -EINVAL;
	}
	if (width < 100	 || width > 10000) {
		pci_err(pdev, "width (%d) out of range\n", width);
		return -EINVAL;
	}
	if (height < 100 || height > 10000) {
		pci_err(pdev, "height (%d) out of range\n", height);
		return -EINVAL;
	}
	pci_info(pdev, "mdpy found: %dx%d framebuffer\n",
		 width, height);

	info = framebuffer_alloc(sizeof(struct mdpy_fb_par), &pdev->dev);
	if (!info)
		goto err_release_regions;
	pci_set_drvdata(pdev, info);
	par = info->par;

	info->fix = mdpy_fb_fix;
	info->fix.smem_start = pci_resource_start(pdev, 0);
	info->fix.smem_len = pci_resource_len(pdev, 0);
	info->fix.line_length = width * 4;

	info->var = mdpy_fb_var;
	info->var.xres = width;
	info->var.yres = height;
	info->var.xres_virtual = width;
	info->var.yres_virtual = height;

	info->screen_size = info->fix.smem_len;
	info->screen_base = ioremap(info->fix.smem_start,
				    info->screen_size);
	if (!info->screen_base) {
		pci_err(pdev, "ioremap(pcibar) failed\n");
		ret = -EIO;
		goto err_release_fb;
	}

	info->apertures = alloc_apertures(1);
	if (!info->apertures) {
		ret = -ENOMEM;
		goto err_unmap;
	}
	info->apertures->ranges[0].base = info->fix.smem_start;
	info->apertures->ranges[0].size = info->fix.smem_len;

	info->fbops = &mdpy_fb_ops;
	info->flags = FBINFO_DEFAULT;
	info->pseudo_palette = par->palette;

	ret = register_framebuffer(info);
	if (ret < 0) {
		pci_err(pdev, "mdpy-fb device register failed: %d\n", ret);
		goto err_unmap;
	}

	pci_info(pdev, "fb%d registered\n", info->node);
	return 0;

err_unmap:
	iounmap(info->screen_base);

err_release_fb:
	framebuffer_release(info);

err_release_regions:
	pci_release_regions(pdev);

	return ret;
}

static void mdpy_fb_remove(struct pci_dev *pdev)
{
	struct fb_info *info = pci_get_drvdata(pdev);

	unregister_framebuffer(info);
	framebuffer_release(info);
}

static struct pci_device_id mdpy_fb_pci_table[] = {
	{
		.vendor	   = MDPY_PCI_VENDOR_ID,
		.device	   = MDPY_PCI_DEVICE_ID,
		.subvendor = MDPY_PCI_SUBVENDOR_ID,
		.subdevice = MDPY_PCI_SUBDEVICE_ID,
	}, {
		/* end of list */
	}
};

static struct pci_driver mdpy_fb_pci_driver = {
	.name		= "mdpy-fb",
	.id_table	= mdpy_fb_pci_table,
	.probe		= mdpy_fb_probe,
	.remove		= mdpy_fb_remove,
};

static int __init mdpy_fb_init(void)
{
	int ret;

	ret = pci_register_driver(&mdpy_fb_pci_driver);
	if (ret)
		return ret;

	return 0;
}

module_init(mdpy_fb_init);

MODULE_DEVICE_TABLE(pci, mdpy_fb_pci_table);
MODULE_LICENSE("GPL v2");
Commit	Line	Data
cacade19 GH	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* Framebuffer driver for mdpy (mediated virtual pci display device).
	4	*
	5	* See mdpy-defs.h for device specs
	6	*
	7	* (c) Gerd Hoffmann <kraxel@redhat.com>
	8	*
	9	* Using some code snippets from simplefb and cirrusfb.
	10	*
	11	* This program is free software; you can redistribute it and/or modify it
	12	* under the terms and conditions of the GNU General Public License,
	13	* version 2, as published by the Free Software Foundation.
	14	*
	15	* This program is distributed in the hope it will be useful, but WITHOUT
	16	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	17	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	18	* more details.
	19	*/
	20	#include <linux/errno.h>
	21	#include <linux/fb.h>
	22	#include <linux/io.h>
	23	#include <linux/pci.h>
	24	#include <linux/module.h>
	25	#include <drm/drm_fourcc.h>
	26	#include "mdpy-defs.h"
	27
	28	static const struct fb_fix_screeninfo mdpy_fb_fix = {
	29	.id = "mdpy-fb",
	30	.type = FB_TYPE_PACKED_PIXELS,
	31	.visual = FB_VISUAL_TRUECOLOR,
	32	.accel = FB_ACCEL_NONE,
	33	};
	34
	35	static const struct fb_var_screeninfo mdpy_fb_var = {
	36	.height = -1,
	37	.width = -1,
	38	.activate = FB_ACTIVATE_NOW,
	39	.vmode = FB_VMODE_NONINTERLACED,
	40
	41	.bits_per_pixel = 32,
	42	.transp.offset = 24,
	43	.red.offset = 16,
	44	.green.offset = 8,
	45	.blue.offset = 0,
	46	.transp.length = 8,
	47	.red.length = 8,
	48	.green.length = 8,
	49	.blue.length = 8,
	50	};
	51
	52	#define PSEUDO_PALETTE_SIZE 16
	53
	54	struct mdpy_fb_par {
	55	u32 palette[PSEUDO_PALETTE_SIZE];
	56	};
	57
	58	static int mdpy_fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
	59	u_int transp, struct fb_info *info)
	60	{
	61	u32 *pal = info->pseudo_palette;
	62	u32 cr = red >> (16 - info->var.red.length);
	63	u32 cg = green >> (16 - info->var.green.length);
	64	u32 cb = blue >> (16 - info->var.blue.length);
65	u32 value, mask;
66
67	if (regno >= PSEUDO_PALETTE_SIZE)
68	return -EINVAL;
69
70	value = (cr << info->var.red.offset) \|
71	(cg << info->var.green.offset) \|
72	(cb << info->var.blue.offset);
73	if (info->var.transp.length > 0) {
74	mask = (1 << info->var.transp.length) - 1;
75	mask <<= info->var.transp.offset;
76	value \|= mask;
77	}
78	pal[regno] = value;
79
80	return 0;
81	}
82
83	static void mdpy_fb_destroy(struct fb_info *info)
84	{
85	if (info->screen_base)
86	iounmap(info->screen_base);
87	}
88
b0077e52	89	static const struct fb_ops mdpy_fb_ops = {
cacade19 GH	90	.owner = THIS_MODULE,
	91	.fb_destroy = mdpy_fb_destroy,
	92	.fb_setcolreg = mdpy_fb_setcolreg,
	93	.fb_fillrect = cfb_fillrect,
	94	.fb_copyarea = cfb_copyarea,
	95	.fb_imageblit = cfb_imageblit,
	96	};
	97
	98	static int mdpy_fb_probe(struct pci_dev *pdev,
	99	const struct pci_device_id *ent)
	100	{
	101	struct fb_info *info;
	102	struct mdpy_fb_par *par;
	103	u32 format, width, height;
	104	int ret;
	105
	106	ret = pci_enable_device(pdev);
	107	if (ret < 0)
	108	return ret;
	109
	110	ret = pci_request_regions(pdev, "mdpy-fb");
	111	if (ret < 0)
	112	return ret;
	113
	114	pci_read_config_dword(pdev, MDPY_FORMAT_OFFSET, &format);
	115	pci_read_config_dword(pdev, MDPY_WIDTH_OFFSET, &width);
	116	pci_read_config_dword(pdev, MDPY_HEIGHT_OFFSET, &height);
	117	if (format != DRM_FORMAT_XRGB8888) {
	118	pci_err(pdev, "format mismatch (0x%x != 0x%x)\n",
	119	format, DRM_FORMAT_XRGB8888);
	120	return -EINVAL;
	121	}
	122	if (width < 100 \|\| width > 10000) {
	123	pci_err(pdev, "width (%d) out of range\n", width);
	124	return -EINVAL;
	125	}
	126	if (height < 100 \|\| height > 10000) {
	127	pci_err(pdev, "height (%d) out of range\n", height);
	128	return -EINVAL;
	129	}
	130	pci_info(pdev, "mdpy found: %dx%d framebuffer\n",
	131	width, height);
	132
	133	info = framebuffer_alloc(sizeof(struct mdpy_fb_par), &pdev->dev);
	134	if (!info)
	135	goto err_release_regions;
	136	pci_set_drvdata(pdev, info);
	137	par = info->par;
	138
	139	info->fix = mdpy_fb_fix;
	140	info->fix.smem_start = pci_resource_start(pdev, 0);
	141	info->fix.smem_len = pci_resource_len(pdev, 0);
	142	info->fix.line_length = width * 4;
	143
	144	info->var = mdpy_fb_var;
	145	info->var.xres = width;
	146	info->var.yres = height;
	147	info->var.xres_virtual = width;
	148	info->var.yres_virtual = height;
	149
	150	info->screen_size = info->fix.smem_len;
	151	info->screen_base = ioremap(info->fix.smem_start,
	152	info->screen_size);
	153	if (!info->screen_base) {
154	pci_err(pdev, "ioremap(pcibar) failed\n");
155	ret = -EIO;
156	goto err_release_fb;
157	}
158
159	info->apertures = alloc_apertures(1);
160	if (!info->apertures) {
161	ret = -ENOMEM;
162	goto err_unmap;
163	}
164	info->apertures->ranges[0].base = info->fix.smem_start;
165	info->apertures->ranges[0].size = info->fix.smem_len;
166
167	info->fbops = &mdpy_fb_ops;
168	info->flags = FBINFO_DEFAULT;
169	info->pseudo_palette = par->palette;
170
171	ret = register_framebuffer(info);
172	if (ret < 0) {
173	pci_err(pdev, "mdpy-fb device register failed: %d\n", ret);
174	goto err_unmap;
175	}
176
177	pci_info(pdev, "fb%d registered\n", info->node);
178	return 0;
179
180	err_unmap:
181	iounmap(info->screen_base);
182
183	err_release_fb:
184	framebuffer_release(info);
185
186	err_release_regions:
187	pci_release_regions(pdev);
188
189	return ret;
190	}
191
192	static void mdpy_fb_remove(struct pci_dev *pdev)
193	{
194	struct fb_info *info = pci_get_drvdata(pdev);
195
196	unregister_framebuffer(info);
197	framebuffer_release(info);
198	}
199
200	static struct pci_device_id mdpy_fb_pci_table[] = {
201	{
202	.vendor = MDPY_PCI_VENDOR_ID,
203	.device = MDPY_PCI_DEVICE_ID,
204	.subvendor = MDPY_PCI_SUBVENDOR_ID,
205	.subdevice = MDPY_PCI_SUBDEVICE_ID,
206	}, {
207	/* end of list */
208	}
209	};
210
211	static struct pci_driver mdpy_fb_pci_driver = {
212	.name = "mdpy-fb",
213	.id_table = mdpy_fb_pci_table,
214	.probe = mdpy_fb_probe,
215	.remove = mdpy_fb_remove,
216	};
217
218	static int __init mdpy_fb_init(void)
219	{
220	int ret;
221
222	ret = pci_register_driver(&mdpy_fb_pci_driver);
223	if (ret)
224	return ret;
225
226	return 0;
227	}
228
229	module_init(mdpy_fb_init);
230
231	MODULE_DEVICE_TABLE(pci, mdpy_fb_pci_table);
232	MODULE_LICENSE("GPL v2");