// 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 <[email protected]>
*
* 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_DEFAULT_IOMEM_OPS,
.fb_destroy = mdpy_fb_destroy,
.fb_setcolreg = mdpy_fb_setcolreg,
};
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)
goto err_disable_dev;
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);
ret = -EINVAL;
goto err_release_regions;
}
if (width < 100 || width > 10000) {
pci_err(pdev, "width (%d) out of range\n", width);
ret = -EINVAL;
goto err_release_regions;
}
if (height < 100 || height > 10000) {
pci_err(pdev, "height (%d) out of range\n", height);
ret = -EINVAL;
goto err_release_regions;
}
pci_info(pdev, "mdpy found: %dx%d framebuffer\n",
width, height);
info = framebuffer_alloc(sizeof(struct mdpy_fb_par), &pdev->dev);
if (!info) {
ret = -ENOMEM;
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->fbops = &mdpy_fb_ops;
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);
err_disable_dev:
pci_disable_device(pdev);
return ret;
}
static void mdpy_fb_remove(struct pci_dev *pdev)
{
struct fb_info *info = pci_get_drvdata(pdev);
unregister_framebuffer(info);
iounmap(info->screen_base);
framebuffer_release(info);
pci_release_regions(pdev);
pci_disable_device(pdev);
}
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_DESCRIPTION("Framebuffer driver for mdpy (mediated virtual pci display device)");
MODULE_LICENSE("GPL v2");
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