Introduce a new sysreset driver for the QEMU Virtual System Controller. This device is found on QEMU "virt" machines (such as the m68k virt target) and provides a mechanism to trigger system reset and power-off events.
The driver maps U-Boot sysreset types to the corresponding controller commands: - SYSRESET_WARM / SYSRESET_COLD -> VIRT_CTRL_CMD_RESET - SYSRESET_POWER_OFF -> VIRT_CTRL_CMD_HALT Signed-off-by: Kuan-Wei Chiu <[email protected]> --- Changes in v6: - Introduce new driver to replace board-file reset implementation. MAINTAINERS | 6 +++ drivers/sysreset/Kconfig | 8 ++++ drivers/sysreset/Makefile | 1 + drivers/sysreset/sysreset_qemu_virt_ctrl.c | 55 ++++++++++++++++++++++ include/qemu_virt_ctrl.h | 13 +++++ 5 files changed, 83 insertions(+) create mode 100644 drivers/sysreset/sysreset_qemu_virt_ctrl.c create mode 100644 include/qemu_virt_ctrl.h diff --git a/MAINTAINERS b/MAINTAINERS index efecb213be7..34081769ecd 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1598,6 +1598,12 @@ S: Maintained T: git https://source.denx.de/u-boot/custodians/u-boot-mpc85xx.git F: arch/powerpc/cpu/mpc85xx/ +QEMU VIRTUAL SYSTEM CONTROLLER +M: Kuan-Wei Chiu <[email protected]> +S: Maintained +F: drivers/sysreset/sysreset_qemu_virt_ctrl.c +F: include/qemu_virt_ctrl.h + RAW NAND M: Dario Binacchi <[email protected]> M: Michael Trimarchi <[email protected]> diff --git a/drivers/sysreset/Kconfig b/drivers/sysreset/Kconfig index 0181f6cd581..120e7510f15 100644 --- a/drivers/sysreset/Kconfig +++ b/drivers/sysreset/Kconfig @@ -298,6 +298,14 @@ config SYSRESET_QCOM_PSHOLD help Add support for the system reboot on Qualcomm SoCs via PSHOLD. +config SYSRESET_QEMU_VIRT_CTRL + bool "QEMU Virtual System Controller support" + depends on SYSRESET + help + Enable support for the QEMU Virtual System Controller. + This device is used in QEMU machines (e.g. m68k virt) to trigger + system reset and poweroff events. + endif endmenu diff --git a/drivers/sysreset/Makefile b/drivers/sysreset/Makefile index f5c78b25896..d18a5d52360 100644 --- a/drivers/sysreset/Makefile +++ b/drivers/sysreset/Makefile @@ -32,3 +32,4 @@ obj-$(CONFIG_$(PHASE_)SYSRESET_X86) += sysreset_x86.o obj-$(CONFIG_SYSRESET_RAA215300) += sysreset_raa215300.o obj-$(CONFIG_SYSRESET_QCOM_PSHOLD) += sysreset_qcom-pshold.o obj-$(CONFIG_TARGET_XTFPGA) += sysreset_xtfpga.o +obj-$(CONFIG_SYSRESET_QEMU_VIRT_CTRL) += sysreset_qemu_virt_ctrl.o diff --git a/drivers/sysreset/sysreset_qemu_virt_ctrl.c b/drivers/sysreset/sysreset_qemu_virt_ctrl.c new file mode 100644 index 00000000000..e7cacc9b6e9 --- /dev/null +++ b/drivers/sysreset/sysreset_qemu_virt_ctrl.c @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2025, Kuan-Wei Chiu <[email protected]> + * + * QEMU Virtual System Controller Driver + */ + +#include <dm.h> +#include <qemu_virt_ctrl.h> +#include <sysreset.h> +#include <asm/io.h> +#include <linux/err.h> + +/* Register offsets */ +#define VIRT_CTRL_REG_FEATURES 0x00 +#define VIRT_CTRL_REG_CMD 0x04 + +/* Commands */ +#define VIRT_CTRL_CMD_NOOP 0x00 +#define VIRT_CTRL_CMD_RESET 0x01 +#define VIRT_CTRL_CMD_HALT 0x02 +#define VIRT_CTRL_CMD_PANIC 0x03 + +static int qemu_virt_ctrl_request(struct udevice *dev, enum sysreset_t type) +{ + struct qemu_virt_ctrl_plat *plat = dev_get_plat(dev); + u32 val; + + switch (type) { + case SYSRESET_WARM: + case SYSRESET_COLD: + val = VIRT_CTRL_CMD_RESET; + break; + case SYSRESET_POWER_OFF: + val = VIRT_CTRL_CMD_HALT; + break; + default: + return -EPROTONOSUPPORT; + } + + writel(val, plat->reg + VIRT_CTRL_REG_CMD); + + return -EINPROGRESS; +} + +static struct sysreset_ops qemu_virt_ctrl_ops = { + .request = qemu_virt_ctrl_request, +}; + +U_BOOT_DRIVER(sysreset_qemu_virt_ctrl) = { + .name = "sysreset_qemu_virt_ctrl", + .id = UCLASS_SYSRESET, + .ops = &qemu_virt_ctrl_ops, + .plat_auto = sizeof(struct qemu_virt_ctrl_plat), +}; diff --git a/include/qemu_virt_ctrl.h b/include/qemu_virt_ctrl.h new file mode 100644 index 00000000000..05aad82b767 --- /dev/null +++ b/include/qemu_virt_ctrl.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2025, Kuan-Wei Chiu <[email protected]> + */ + +#ifndef _QEMU_VIRT_CTRL_H_ +#define _QEMU_VIRT_CTRL_H_ + +struct qemu_virt_ctrl_plat { + phys_addr_t reg; +}; + +#endif /* _QEMU_VIRT_CTRL_H_ */ -- 2.52.0.457.g6b5491de43-goog
