Add support for the QEMU 'virt' machine on the m68k architecture. This board emulates a generic machine based on the Motorola 68040 CPU equipped with Goldfish virtual peripherals.
Introduce the necessary board configuration and initialization infrastructure. The implementation includes logic to parse the QEMU bootinfo interface, enabling dynamic detection of system RAM size to adapt to the virtual machine's configuration. Enable the Goldfish TTY driver for serial console output. Additionally, enable Goldfish RTC and timer drivers to support real-time clock functionality and nanosecond-resolution delays. Include comprehensive documentation covering build instructions and usage examples. Signed-off-by: Kuan-Wei Chiu <[email protected]> Tested-by: Daniel Palmer <[email protected]> --- Changes in v6: - Move bootinfo parsing logic to a helper function called in board_early_init_f. - Remove hardcoded MMIO address macros; use values parsed from bootinfo. - Use the new sysreset driver via U_BOOT_DRVINFO. - Use SZ_16M macro for default RAM size. - Update header include order to match coding style. - Fix blank line formatting in checkboard(). arch/m68k/Kconfig | 9 ++ board/emulation/qemu-m68k/Kconfig | 12 +++ board/emulation/qemu-m68k/MAINTAINERS | 8 ++ board/emulation/qemu-m68k/Makefile | 5 ++ board/emulation/qemu-m68k/qemu-m68k.c | 117 ++++++++++++++++++++++++++ configs/qemu-m68k_defconfig | 20 +++++ doc/board/emulation/index.rst | 1 + doc/board/emulation/qemu-m68k.rst | 39 +++++++++ include/configs/qemu-m68k.h | 18 ++++ 9 files changed, 229 insertions(+) create mode 100644 board/emulation/qemu-m68k/Kconfig create mode 100644 board/emulation/qemu-m68k/MAINTAINERS create mode 100644 board/emulation/qemu-m68k/Makefile create mode 100644 board/emulation/qemu-m68k/qemu-m68k.c create mode 100644 configs/qemu-m68k_defconfig create mode 100644 doc/board/emulation/qemu-m68k.rst create mode 100644 include/configs/qemu-m68k.h diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index f5c0dc037b4..774b119cb4b 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -194,6 +194,14 @@ config TARGET_STMARK2 select CF_DSPI 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. + endchoice config SYS_CPU @@ -222,6 +230,7 @@ source "board/freescale/m5329evb/Kconfig" source "board/freescale/m5373evb/Kconfig" source "board/sysam/amcore/Kconfig" source "board/sysam/stmark2/Kconfig" +source "board/emulation/qemu-m68k/Kconfig" config M68K_QEMU bool "Build with workarounds for incomplete QEMU emulation" diff --git a/board/emulation/qemu-m68k/Kconfig b/board/emulation/qemu-m68k/Kconfig new file mode 100644 index 00000000000..aae6dfe400f --- /dev/null +++ b/board/emulation/qemu-m68k/Kconfig @@ -0,0 +1,12 @@ +if TARGET_QEMU_M68K + +config SYS_BOARD + default "qemu-m68k" + +config SYS_VENDOR + default "emulation" + +config SYS_CONFIG_NAME + default "qemu-m68k" + +endif diff --git a/board/emulation/qemu-m68k/MAINTAINERS b/board/emulation/qemu-m68k/MAINTAINERS new file mode 100644 index 00000000000..90414c58465 --- /dev/null +++ b/board/emulation/qemu-m68k/MAINTAINERS @@ -0,0 +1,8 @@ +QEMU M68K VIRT BOARD +M: Kuan-Wei Chiu <[email protected]> +S: Maintained +F: board/emulation/qemu-m68k/ +F: board/emulation/common/ +F: include/configs/qemu-m68k.h +F: configs/qemu-m68k_defconfig +F: doc/board/emulation/qemu-m68k.rst diff --git a/board/emulation/qemu-m68k/Makefile b/board/emulation/qemu-m68k/Makefile new file mode 100644 index 00000000000..5cb2886ff5a --- /dev/null +++ b/board/emulation/qemu-m68k/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0-or-later +# +# Copyright (C) 2025, Kuan-Wei Chiu <[email protected]> + +obj-y += qemu-m68k.o diff --git a/board/emulation/qemu-m68k/qemu-m68k.c b/board/emulation/qemu-m68k/qemu-m68k.c new file mode 100644 index 00000000000..d3527aee112 --- /dev/null +++ b/board/emulation/qemu-m68k/qemu-m68k.c @@ -0,0 +1,117 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2025, Kuan-Wei Chiu <[email protected]> + */ + +#include <config.h> +#include <goldfish_rtc.h> +#include <goldfish_timer.h> +#include <goldfish_tty.h> +#include <init.h> +#include <qemu_virt_ctrl.h> +#include <serial.h> +#include <asm-generic/sections.h> +#include <asm/bootinfo.h> +#include <asm/global_data.h> +#include <asm/io.h> +#include <dm/platdata.h> +#include <linux/errno.h> +#include <linux/sizes.h> + +DECLARE_GLOBAL_DATA_PTR; + +static struct goldfish_tty_plat serial_plat; +static struct goldfish_rtc_plat rtc_plat; +static struct goldfish_timer_plat timer_plat; +static struct qemu_virt_ctrl_plat reset_plat; + +/* + * Theoretical limit derivation: + * Max Bootinfo Size (Standard Page) = 4096 bytes + * Min Record Size (Tag + Size) = 4 bytes + * Max Records = 4096 / 4 = 1024 + */ +#define MAX_BOOTINFO_RECORDS 1024 + +static void parse_bootinfo(void) +{ + struct bi_record *record; + ulong addr; + int loops = 0; + + /* QEMU places bootinfo after _end, aligned to 2 bytes */ + addr = (ulong)&_end; + addr = ALIGN(addr, 2); + + record = (struct bi_record *)addr; + + if (record->tag != BI_MACHTYPE) + return; + + while (record->tag != BI_LAST) { + phys_addr_t base = record->data[0]; + + if (++loops > MAX_BOOTINFO_RECORDS) + panic("Bootinfo loop exceeded"); + + switch (record->tag) { + case BI_VIRT_GF_TTY_BASE: + serial_plat.reg = base; + break; + case BI_VIRT_GF_RTC_BASE: + rtc_plat.reg = base; + timer_plat.reg = base; + break; + case BI_VIRT_CTRL_BASE: + reset_plat.reg = base; + break; + case BI_MEMCHUNK: + gd->ram_size = record->data[1]; + break; + } + record = (struct bi_record *)((ulong)record + record->size); + } +} + +int board_early_init_f(void) +{ + parse_bootinfo(); + + return 0; +} + +int checkboard(void) +{ + puts("Board: QEMU m68k virt\n"); + + return 0; +} + +int dram_init(void) +{ + /* Default: 16MB */ + if (!gd->ram_size) + gd->ram_size = SZ_16M; + + return 0; +} + +U_BOOT_DRVINFO(goldfish_rtc) = { + .name = "rtc_goldfish", + .plat = &rtc_plat, +}; + +U_BOOT_DRVINFO(goldfish_timer) = { + .name = "goldfish_timer", + .plat = &timer_plat, +}; + +U_BOOT_DRVINFO(goldfish_serial) = { + .name = "serial_goldfish", + .plat = &serial_plat, +}; + +U_BOOT_DRVINFO(sysreset_qemu_virt_ctrl) = { + .name = "sysreset_qemu_virt_ctrl", + .plat = &reset_plat, +}; diff --git a/configs/qemu-m68k_defconfig b/configs/qemu-m68k_defconfig new file mode 100644 index 00000000000..d667791d93b --- /dev/null +++ b/configs/qemu-m68k_defconfig @@ -0,0 +1,20 @@ +CONFIG_M68K=y +CONFIG_TEXT_BASE=0x00000000 +CONFIG_SYS_MALLOC_LEN=0x20000 +CONFIG_SYS_MALLOC_F_LEN=0x2000 +CONFIG_SYS_MONITOR_LEN=262144 +CONFIG_SYS_BOOTM_LEN=0x1000000 +CONFIG_SYS_LOAD_ADDR=0x00000000 +CONFIG_TARGET_QEMU_M68K=y +# CONFIG_DISPLAY_BOARDINFO is not set +CONFIG_BOARD_EARLY_INIT_F=y +CONFIG_CMD_POWEROFF=y +CONFIG_DM_RTC=y +CONFIG_RTC_GOLDFISH=y +CONFIG_DM_SERIAL=y +CONFIG_SERIAL_GOLDFISH=y +CONFIG_SYSRESET=y +CONFIG_SYSRESET_CMD_POWEROFF=y +CONFIG_SYSRESET_QEMU_VIRT_CTRL=y +CONFIG_TIMER=y +CONFIG_GOLDFISH_TIMER=y diff --git a/doc/board/emulation/index.rst b/doc/board/emulation/index.rst index f8908166276..4f7c812d493 100644 --- a/doc/board/emulation/index.rst +++ b/doc/board/emulation/index.rst @@ -15,6 +15,7 @@ Emulation qemu-sbsa qemu-x86 qemu-xtensa + qemu-m68k Also see diff --git a/doc/board/emulation/qemu-m68k.rst b/doc/board/emulation/qemu-m68k.rst new file mode 100644 index 00000000000..6c4de54cf6a --- /dev/null +++ b/doc/board/emulation/qemu-m68k.rst @@ -0,0 +1,39 @@ +.. SPDX-License-Identifier: GPL-2.0-or-later +.. Copyright (C) 2025, Kuan-Wei Chiu <[email protected]> + +QEMU m68k +========= + +QEMU for m68k supports a special 'virt' machine designed for emulation and +virtualization purposes. This document describes how to run U-Boot under it. + +The QEMU virt machine models a generic m68k virtual machine with Goldfish +interfaces. It supports the Motorola 68040 CPU architecture. + +Building U-Boot +--------------- +Set the CROSS_COMPILE environment variable to your m68k toolchain, and run: + +.. code-block:: bash + + export CROSS_COMPILE=m68k-linux-gnu- + make qemu-m68k_defconfig + make + +Running U-Boot +-------------- +The minimal QEMU command line to get U-Boot up and running is: + +.. code-block:: bash + + qemu-system-m68k -M virt -cpu m68040 -nographic -kernel u-boot + +Note that the `-nographic` option is used to redirect the console to stdio, +which connects to the emulated Goldfish TTY device. + +Hardware Support +---------------- +The following QEMU virt peripherals are supported in U-Boot: + +* Goldfish TTY (Serial Console) +* Goldfish RTC (Real Time Clock) diff --git a/include/configs/qemu-m68k.h b/include/configs/qemu-m68k.h new file mode 100644 index 00000000000..1d8aa92fe80 --- /dev/null +++ b/include/configs/qemu-m68k.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2025, Kuan-Wei Chiu <[email protected]> + */ + +#ifndef __QEMU_M68K_H +#define __QEMU_M68K_H + +/* Memory Configuration */ +#define CFG_SYS_SDRAM_BASE 0x00000000 + +/* + * Initial Stack Pointer: + * Place the stack at 4MB offset to avoid overwriting U-Boot code/data. + */ +#define CFG_SYS_INIT_SP_ADDR (CFG_SYS_SDRAM_BASE + 0x400000) + +#endif /* __QEMU_M68K_H */ -- 2.52.0.457.g6b5491de43-goog
