Re: [PATCH v4 6/6] board: qemu: m68k: Create virtio mmio instances

Kuan-Wei Chiu
2026-04-16T09:29:42Z

On Mon, Apr 13, 2026 at 06:22:40PM +0900, Daniel Palmer wrote:
> So that you can use virtio network, block etc create the virtio mmio
> instances. There are 128 of these even if they are not all used, a
> single mmio base value is passed via bootinfo.
>
> Signed-off-by: Daniel Palmer <daniel@thingy.jp>

Reviewed-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Tested-by: Kuan-Wei Chiu <visitorckw@gmail.com>

Regards,
Kuan-Wei

> ---
> arch/m68k/Kconfig | 14 +++++----
> board/emulation/qemu-m68k/qemu-m68k.c | 45 +++++++++++++++++++++++++++
> 2 files changed, 53 insertions(+), 6 deletions(-)
>
> diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
> index 6ce8f577e3a1..20a112880c87 100644
> --- a/arch/m68k/Kconfig
> +++ b/arch/m68k/Kconfig
> @@ -195,12 +195,14 @@ config TARGET_STMARK2
> select M54418
>
> config TARGET_QEMU_M68K
> - bool "Support QEMU m68k virt"
> - select M68040
> - imply CMD_DM
> - help
> - This target supports the QEMU m68k virtual machine (-M virt).
> - It simulates a Motorola 68040 CPU with Goldfish peripherals.
> + bool "Support QEMU m68k virt"
> + select M68040
> + select BOARD_EARLY_INIT_R
> + select VIRTIO_MMIO
> + imply CMD_DM
> + help
> + This target supports the QEMU m68k virtual machine (-M virt).
> + It simulates a Motorola 68040 CPU with Goldfish peripherals.
>
> endchoice
>
> diff --git a/board/emulation/qemu-m68k/qemu-m68k.c b/board/emulation/qemu-m68k/qemu-m68k.c
> index d3527aee1128..a19b23a28ce3 100644
> --- a/board/emulation/qemu-m68k/qemu-m68k.c
> +++ b/board/emulation/qemu-m68k/qemu-m68k.c
> @@ -14,9 +14,14 @@
> #include <asm/bootinfo.h>
> #include <asm/global_data.h>
> #include <asm/io.h>
> +#include <dm.h>
> +#include <dm/device-internal.h>
> +#include <dm/lists.h>
> #include <dm/platdata.h>
> +#include <dm/root.h>
> #include <linux/errno.h>
> #include <linux/sizes.h>
> +#include <virtio_mmio.h>
>
> DECLARE_GLOBAL_DATA_PTR;
>
> @@ -25,6 +30,38 @@ static struct goldfish_rtc_plat rtc_plat;
> static struct goldfish_timer_plat timer_plat;
> static struct qemu_virt_ctrl_plat reset_plat;
>
> +#define VIRTIO_MMIO_NUM 128
> +#define VIRTIO_MMIO_SZ 0x200
> +
> +static struct virtio_mmio_plat virtio_mmio_plat[VIRTIO_MMIO_NUM];
> +static char virtio_mmio_names[VIRTIO_MMIO_NUM][11];
> +static phys_addr_t virtio_mmio_base;
> +
> +static int create_virtio_mmios(void)
> +{
> + struct driver *drv;
> + int i, ret;
> +
> + if (!virtio_mmio_base)
> + return -ENODEV;
> +
> + drv = lists_driver_lookup_name("virtio-mmio");
> + if (!drv)
> + return -ENOENT;
> +
> + for (i = 0; i < VIRTIO_MMIO_NUM; i++) {
> + virtio_mmio_plat[i].base = virtio_mmio_base + (VIRTIO_MMIO_SZ * i);
> + sprintf(virtio_mmio_names[i], "virtio-%d", i);
> +
> + ret = device_bind(dm_root(), drv, virtio_mmio_names[i],
> + &virtio_mmio_plat[i], ofnode_null(), NULL);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> /*
> * Theoretical limit derivation:
> * Max Bootinfo Size (Standard Page) = 4096 bytes
> @@ -65,6 +102,9 @@ static void parse_bootinfo(void)
> case BI_VIRT_CTRL_BASE:
> reset_plat.reg = base;
> break;
> + case BI_VIRT_VIRTIO_BASE:
> + virtio_mmio_base = base;
> + break;
> case BI_MEMCHUNK:
> gd->ram_size = record->data[1];
> break;
> @@ -80,6 +120,11 @@ int board_early_init_f(void)
> return 0;
> }
>
> +int board_early_init_r(void)
> +{
> + return create_virtio_mmios();
> +}
> +
> int checkboard(void)
> {
> puts("Board: QEMU m68k virt\n");
> --
> 2.51.0
>