On Thu, 07 Nov 2019 13:24:08 PST (-0800), Christoph Hellwig wrote:
Add a trivial poweroff driver for the qemu-virt test device that
allows an oderly shutdown of the VM.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
arch/riscv/configs/defconfig | 2 +
drivers/power/reset/Kconfig | 8 ++++
drivers/power/reset/Makefile | 1 +
.../power/reset/qemu-riscv-virt-poweroff.c | 47 +++++++++++++++++++
4 files changed, 58 insertions(+)
create mode 100644 drivers/power/reset/qemu-riscv-virt-poweroff.c
diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig
index 420a0dbef386..47da87725b5e 100644
--- a/arch/riscv/configs/defconfig
+++ b/arch/riscv/configs/defconfig
@@ -63,6 +63,8 @@ CONFIG_HW_RANDOM_VIRTIO=y
CONFIG_SPI=y
CONFIG_SPI_SIFIVE=y
# CONFIG_PTP_1588_CLOCK is not set
+CONFIG_POWER_RESET=y
+CONFIG_QEMU_RISCV_VIRT_POWEROFF=y
CONFIG_DRM=y
CONFIG_DRM_RADEON=y
CONFIG_DRM_VIRTIO_GPU=y
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index a564237278ff..56cb18520850 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -256,5 +256,13 @@ config NVMEM_REBOOT_MODE
then the bootloader can read it and take different
action according to the mode.
+config QEMU_RISCV_VIRT_POWEROFF
+ tristate "QEMU RISC-V virt machine poweroff driver"
+ depends on OF
+ depends on RISCV || COMPILE_TEST
+ help
+ Say y here to allow RISC-V Qemu VMs to be shut down by
+ the kernel.
+
endif
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 85da3198e4e0..b3094016b634 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -30,3 +30,4 @@ obj-$(CONFIG_REBOOT_MODE) += reboot-mode.o
obj-$(CONFIG_SYSCON_REBOOT_MODE) += syscon-reboot-mode.o
obj-$(CONFIG_POWER_RESET_SC27XX) += sc27xx-poweroff.o
obj-$(CONFIG_NVMEM_REBOOT_MODE) += nvmem-reboot-mode.o
+obj-$(CONFIG_QEMU_RISCV_VIRT_POWEROFF) += qemu-riscv-virt-poweroff.o
diff --git a/drivers/power/reset/qemu-riscv-virt-poweroff.c b/drivers/power/reset/qemu-riscv-virt-poweroff.c
new file mode 100644
index 000000000000..5b9a12dd853b
--- /dev/null
+++ b/drivers/power/reset/qemu-riscv-virt-poweroff.c
@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 Christoph Hellwig.
+ */
+
+#include <linux/reboot.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/of_address.h>
+#include <linux/module.h>
+
+#define VIRT_TEST_FINISHER_PASS 0x5555
+
+static u16 __iomem *test_addr;
+
+static void qemu_virt_power_off(void)
+{
+ writew(VIRT_TEST_FINISHER_PASS, test_addr);
+}
+
+static int sifive_test_probe(struct platform_device *pdev)
+{
+ /* there can only be a single instance */
+ if (WARN_ON_ONCE(test_addr))
+ return -EINVAL;
+
+ test_addr = of_iomap(pdev->dev.of_node, 0);
+ if (!test_addr)
+ return -EINVAL;
+ pm_power_off = qemu_virt_power_off;
+ return 0;
+}
+
+static const struct of_device_id sifive_test_of_match[] = {
+ { .compatible = "sifive,test0", },
+ {},
+};
+
+static struct platform_driver sifive_test_driver = {
+ .probe = sifive_test_probe,
+ .driver = {
+ .name = "sifive_test",
+ .of_match_table = sifive_test_of_match,
+ },
+};
+module_platform_driver(sifive_test_driver);
Reviewed-by: Palmer Dabbelt <palmer@xxxxxxxxxxx>
