sample: vfio mdev display - guest driver
Guest fbdev driver for CONFIG_SAMPLE_VFIO_MDEV_MDPY.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
diff --git a/samples/Kconfig b/samples/Kconfig
index 960f19b..a6ff147 100644
--- a/samples/Kconfig
+++ b/samples/Kconfig
@@ -123,6 +123,15 @@
mediated device. It is a simple framebuffer and supports
the region display interface (VFIO_GFX_PLANE_TYPE_REGION).
+config SAMPLE_VFIO_MDEV_MDPY_FB
+ tristate "Build VFIO mdpy example guest fbdev driver -- loadable module only"
+ depends on FB && m
+ select FB_CFB_FILLRECT
+ select FB_CFB_COPYAREA
+ select FB_CFB_IMAGEBLIT
+ help
+ Guest fbdev driver for the virtual display sample driver.
+
config SAMPLE_STATX
bool "Build example extended-stat using code"
depends on BROKEN
diff --git a/samples/vfio-mdev/Makefile b/samples/vfio-mdev/Makefile
index 031d6b8..7a5790a 100644
--- a/samples/vfio-mdev/Makefile
+++ b/samples/vfio-mdev/Makefile
@@ -1,2 +1,3 @@
obj-$(CONFIG_SAMPLE_VFIO_MDEV_MTTY) += mtty.o
obj-$(CONFIG_SAMPLE_VFIO_MDEV_MDPY) += mdpy.o
+obj-$(CONFIG_SAMPLE_VFIO_MDEV_MDPY_FB) += mdpy-fb.o
diff --git a/samples/vfio-mdev/mdpy-fb.c b/samples/vfio-mdev/mdpy-fb.c
new file mode 100644
index 0000000..2719bb2
--- /dev/null
+++ b/samples/vfio-mdev/mdpy-fb.c
@@ -0,0 +1,232 @@
+// 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 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");
