Hi Simon,
On Sun, Apr 30, 2023 at 10:32 AM Simon Glass sjg@chromium.org wrote:
Bochs is convenient with QEMU on x86 since it does not require a video BIOS. Add a driver for it.
Signed-off-by: Simon Glass sjg@chromium.org
drivers/video/Kconfig | 30 ++++++++++ drivers/video/Makefile | 2 + drivers/video/bochs.c | 130 +++++++++++++++++++++++++++++++++++++++++ drivers/video/bochs.h | 36 ++++++++++++ 4 files changed, 198 insertions(+) create mode 100644 drivers/video/bochs.c create mode 100644 drivers/video/bochs.h
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig index 9a95b7a4c792..5fd42807179f 100644 --- a/drivers/video/Kconfig +++ b/drivers/video/Kconfig @@ -278,6 +278,36 @@ config VIDCONSOLE_AS_NAME possible to update the environment, the breakage may be confusing for users. This option will be removed around the end of 2020.
+config VIDEO_BOCHS
bool "Enable Bochs video emulation for QEMU"depends on X86helpEnable this to use the Boschs video support provided in the QEMUemulator. This appears as a PCI device which U-Boot can set up toprovide a frame buffer.+if VIDEO_BOCHS
+config VIDEO_BOCHS_SIZE_X
int "Width of display (X resolution)"default 1280helpSets the width of the display.These two options control the size of the display set up by QEMU.Typical sizes are 1024 x 768 or 1280 x 1024.+config VIDEO_BOCHS_SIZE_Y
int "High of display (Y resolution)"default 1024helpSets the height of the display.These two options control the size of the display set up by QEMU.Typical sizes are 1024 x 768 or 1280 x 1024.+endif
config VIDEO_COREBOOT bool "Enable coreboot framebuffer driver support" depends on X86 diff --git a/drivers/video/Makefile b/drivers/video/Makefile index a609e35d22e8..11d872ddf41d 100644 --- a/drivers/video/Makefile +++ b/drivers/video/Makefile @@ -28,6 +28,8 @@ obj-$(CONFIG_VIDEO_LOGO) += u_boot_logo.o
endif
+obj-$(CONFIG_VIDEO_BOCHS) += bochs.o
obj-${CONFIG_EXYNOS_FB} += exynos/ obj-${CONFIG_VIDEO_ROCKCHIP} += rockchip/ obj-${CONFIG_VIDEO_STM32} += stm32/ diff --git a/drivers/video/bochs.c b/drivers/video/bochs.c new file mode 100644 index 000000000000..7ea29a0ed177 --- /dev/null +++ b/drivers/video/bochs.c @@ -0,0 +1,130 @@ +// SPDX-License-Identifier: GPL-2.0 +/*
- Modified from coreboot bochs.c
- */
+#define LOG_CATEGORY UCLASS_VIDEO
+#include <common.h> +#include <dm.h> +#include <log.h> +#include <pci.h> +#include <video.h> +#include <asm/io.h> +#include <asm/mtrr.h> +#include <linux/sizes.h> +#include "bochs.h"
+static int xsize = CONFIG_VIDEO_BOCHS_SIZE_X; +static int ysize = CONFIG_VIDEO_BOCHS_SIZE_Y;
+static void bochs_write(void *mmio, int index, int val) +{
writew(val, mmio + MMIO_BASE + index * 2);+}
+static int bochs_read(void *mmio, int index) +{
return readw(mmio + MMIO_BASE + index * 2);+}
+static void bochs_vga_write(int index, uint8_t val) +{
outb(val, VGA_INDEX);+}
+static int bochs_init_linear_fb(struct udevice *dev) +{
struct video_uc_plat *plat = dev_get_uclass_plat(dev);struct video_priv *uc_priv = dev_get_uclass_priv(dev);ulong fb;void *mmio;int id, mem;log_debug("probing %s at PCI %x\n", dev->name, dm_pci_get_bdf(dev));fb = dm_pci_read_bar32(dev, 0);if (!fb)return log_msg_ret("fb", -EIO);/* MMIO bar supported since qemu 3.0+ */mmio = dm_pci_map_bar(dev, PCI_BASE_ADDRESS_2, 0, 0, PCI_REGION_TYPE,PCI_REGION_MEM);if (!mmio)return log_msg_ret("map", -EIO);log_debug("QEMU VGA: bochs @ %p: %d MiB FB at %lx\n", mmio, mem / SZ_1M,fb);
mem is uninitialized yet at this point, until (see below)
/* bochs dispi detection */id = bochs_read(mmio, INDEX_ID);if ((id & 0xfff0) != ID0) {log_debug("ID mismatch\n");return -EPROTONOSUPPORT;}mem = bochs_read(mmio, INDEX_VIDEO_MEMORY_64K) * SZ_64K;
it reaches this line
uc_priv->xsize = xsize;uc_priv->ysize = ysize;uc_priv->bpix = VIDEO_BPP32;/* setup video mode */bochs_write(mmio, INDEX_ENABLE, 0);bochs_write(mmio, INDEX_BANK, 0);bochs_write(mmio, INDEX_BPP, VNBITS(uc_priv->bpix));bochs_write(mmio, INDEX_XRES, xsize);bochs_write(mmio, INDEX_YRES, ysize);bochs_write(mmio, INDEX_VIRT_WIDTH, xsize);bochs_write(mmio, INDEX_VIRT_HEIGHT, ysize);bochs_write(mmio, INDEX_X_OFFSET, 0);bochs_write(mmio, INDEX_Y_OFFSET, 0);bochs_write(mmio, INDEX_ENABLE, ENABLED | LFB_ENABLED);bochs_vga_write(0, 0x20); /* disable blanking */plat->base = fb;return 0;+}
+static int bochs_video_probe(struct udevice *dev) +{
int ret;ret = bochs_init_linear_fb(dev);if (ret)return log_ret(ret);return 0;+}
+static int bochs_video_bind(struct udevice *dev) +{
struct video_uc_plat *uc_plat = dev_get_uclass_plat(dev);/* Set the maximum supported resolution */uc_plat->size = 2560 * 1600 * 4;log_debug("%s: Frame buffer size %x\n", __func__, uc_plat->size);return 0;+}
+static const struct udevice_id bochs_video_ids[] = {
{ .compatible = "bochs-fb" },{ }+};
+U_BOOT_DRIVER(bochs_video) = {
.name = "bochs_video",.id = UCLASS_VIDEO,.of_match = bochs_video_ids,.bind = bochs_video_bind,.probe = bochs_video_probe,+};
+static struct pci_device_id bochs_video_supported[] = {
{ PCI_DEVICE(0x1234, 0x1111) },{ },+};
+U_BOOT_PCI_DEVICE(bochs_video, bochs_video_supported); diff --git a/drivers/video/bochs.h b/drivers/video/bochs.h new file mode 100644 index 000000000000..4c8ec83a550e --- /dev/null +++ b/drivers/video/bochs.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/*
- Modified from coreboot bochs.c
- */
+#ifndef __BOCHS_H +#define __BOCHS_H
+#define VGA_INDEX 0x3c0
+#define IOPORT_INDEX 0x01ce +#define IOPORT_DATA 0x01cf
+enum {
INDEX_ID,INDEX_XRES,INDEX_YRES,INDEX_BPP,INDEX_ENABLE,INDEX_BANK,INDEX_VIRT_WIDTH,INDEX_VIRT_HEIGHT,INDEX_X_OFFSET,INDEX_Y_OFFSET,INDEX_VIDEO_MEMORY_64K+};
+#define ID0 0xb0c0
+#define ENABLED BIT(0) +#define LFB_ENABLED BIT(6) +#define NOCLEARMEM BIT(7)
+#define MMIO_BASE 0x500
+#endif
Regards, Bin