[PATCH v5 8/8] board: qemu: m68k: Create virtio mmio instances

Daniel Palmer
2026-04-16T09:41:25Z

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.

Reviewed-by: Angelo Dureghello <angelo@kernel-space.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Daniel Palmer <daniel@thingy.jp>
---
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