From 64f89dfaa4f155e3797191286aac6e60f404725f Mon Sep 17 00:00:00 2001 From: Hitomi Hasegawa Date: Fri, 20 May 2022 16:41:19 +0900 Subject: [PATCH] soc: fujitsu: Add A64FX diagnostic interrupt driver Register the NMI/IRQ corresponding to the A64FX's device definition dedicated to diagnostic interrupts, so that when this interrupt is sent using the BMC, it causes a panic. This can be used to obtain a kernel dump. Signed-off-by: Hitomi Hasegawa Link: https://lore.kernel.org/r/20220520074119.3574753-2-hasegawa-hitomi@fujitsu.com' Signed-off-by: Arnd Bergmann --- MAINTAINERS | 5 + drivers/soc/Kconfig | 1 + drivers/soc/Makefile | 1 + drivers/soc/fujitsu/Kconfig | 16 ++++ drivers/soc/fujitsu/Makefile | 3 + drivers/soc/fujitsu/a64fx-diag.c | 154 +++++++++++++++++++++++++++++++ 6 files changed, 180 insertions(+) create mode 100644 drivers/soc/fujitsu/Kconfig create mode 100644 drivers/soc/fujitsu/Makefile create mode 100644 drivers/soc/fujitsu/a64fx-diag.c diff --git a/MAINTAINERS b/MAINTAINERS index 2ef5b11cd813..49cb2d39c421 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -242,6 +242,11 @@ F: include/trace/events/9p.h F: include/uapi/linux/virtio_9p.h F: net/9p/ +A64FX DIAG DRIVER +M: Hitomi Hasegawa +S: Supported +F: drivers/soc/fujitsu/a64fx-diag.c + A8293 MEDIA DRIVER M: Antti Palosaari L: linux-media@vger.kernel.org diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig index 86ccf5970bc1..e461c071189b 100644 --- a/drivers/soc/Kconfig +++ b/drivers/soc/Kconfig @@ -9,6 +9,7 @@ source "drivers/soc/atmel/Kconfig" source "drivers/soc/bcm/Kconfig" source "drivers/soc/canaan/Kconfig" source "drivers/soc/fsl/Kconfig" +source "drivers/soc/fujitsu/Kconfig" source "drivers/soc/imx/Kconfig" source "drivers/soc/ixp4xx/Kconfig" source "drivers/soc/litex/Kconfig" diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile index 919716e0e700..69ba6508cf2c 100644 --- a/drivers/soc/Makefile +++ b/drivers/soc/Makefile @@ -12,6 +12,7 @@ obj-$(CONFIG_SOC_CANAAN) += canaan/ obj-$(CONFIG_ARCH_DOVE) += dove/ obj-$(CONFIG_MACH_DOVE) += dove/ obj-y += fsl/ +obj-y += fujitsu/ obj-$(CONFIG_ARCH_GEMINI) += gemini/ obj-y += imx/ obj-y += ixp4xx/ diff --git a/drivers/soc/fujitsu/Kconfig b/drivers/soc/fujitsu/Kconfig new file mode 100644 index 000000000000..56275b44b293 --- /dev/null +++ b/drivers/soc/fujitsu/Kconfig @@ -0,0 +1,16 @@ +# SPDX-License-Identifier: GPL-2.0-only +menu "fujitsu SoC drivers" + +config A64FX_DIAG + tristate "A64FX diag driver" + depends on ARM64 + depends on ACPI + help + Say Y here if you want to enable diag interrupt on Fujitsu A64FX. + This driver enables BMC's diagnostic requests and enables + A64FX-specific interrupts. This allows administrators to obtain + kernel dumps via diagnostic requests using ipmitool, etc. + + If unsure, say N. + +endmenu diff --git a/drivers/soc/fujitsu/Makefile b/drivers/soc/fujitsu/Makefile new file mode 100644 index 000000000000..945bc1c14ad0 --- /dev/null +++ b/drivers/soc/fujitsu/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_A64FX_DIAG) += a64fx-diag.o diff --git a/drivers/soc/fujitsu/a64fx-diag.c b/drivers/soc/fujitsu/a64fx-diag.c new file mode 100644 index 000000000000..d87f348427bf --- /dev/null +++ b/drivers/soc/fujitsu/a64fx-diag.c @@ -0,0 +1,154 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * A64FX diag driver. + * Copyright (c) 2022 Fujitsu Ltd. + */ + +#include +#include +#include +#include +#include + +#define A64FX_DIAG_IRQ 1 +#define BMC_DIAG_INTERRUPT_ENABLE 0x40 +#define BMC_DIAG_INTERRUPT_STATUS 0x44 +#define BMC_DIAG_INTERRUPT_MASK BIT(31) + +struct a64fx_diag_priv { + void __iomem *mmsc_reg_base; + int irq; + bool has_nmi; +}; + +static irqreturn_t a64fx_diag_handler_nmi(int irq, void *dev_id) +{ + nmi_panic(NULL, "a64fx_diag: interrupt received\n"); + + return IRQ_HANDLED; +} + +static irqreturn_t a64fx_diag_handler_irq(int irq, void *dev_id) +{ + panic("a64fx_diag: interrupt received\n"); + + return IRQ_HANDLED; +} + +static void a64fx_diag_interrupt_clear(struct a64fx_diag_priv *priv) +{ + void __iomem *diag_status_reg_addr; + u32 mmsc; + + diag_status_reg_addr = priv->mmsc_reg_base + BMC_DIAG_INTERRUPT_STATUS; + mmsc = readl(diag_status_reg_addr); + if (mmsc & BMC_DIAG_INTERRUPT_MASK) + writel(BMC_DIAG_INTERRUPT_MASK, diag_status_reg_addr); +} + +static void a64fx_diag_interrupt_enable(struct a64fx_diag_priv *priv) +{ + void __iomem *diag_enable_reg_addr; + u32 mmsc; + + diag_enable_reg_addr = priv->mmsc_reg_base + BMC_DIAG_INTERRUPT_ENABLE; + mmsc = readl(diag_enable_reg_addr); + if (!(mmsc & BMC_DIAG_INTERRUPT_MASK)) { + mmsc |= BMC_DIAG_INTERRUPT_MASK; + writel(mmsc, diag_enable_reg_addr); + } +} + +static void a64fx_diag_interrupt_disable(struct a64fx_diag_priv *priv) +{ + void __iomem *diag_enable_reg_addr; + u32 mmsc; + + diag_enable_reg_addr = priv->mmsc_reg_base + BMC_DIAG_INTERRUPT_ENABLE; + mmsc = readl(diag_enable_reg_addr); + if (mmsc & BMC_DIAG_INTERRUPT_MASK) { + mmsc &= ~BMC_DIAG_INTERRUPT_MASK; + writel(mmsc, diag_enable_reg_addr); + } +} + +static int a64fx_diag_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct a64fx_diag_priv *priv; + unsigned long irq_flags; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (priv == NULL) + return -ENOMEM; + + priv->mmsc_reg_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->mmsc_reg_base)) + return PTR_ERR(priv->mmsc_reg_base); + + priv->irq = platform_get_irq(pdev, A64FX_DIAG_IRQ); + if (priv->irq < 0) + return priv->irq; + + platform_set_drvdata(pdev, priv); + + irq_flags = IRQF_PERCPU | IRQF_NOBALANCING | IRQF_NO_AUTOEN | + IRQF_NO_THREAD; + ret = request_nmi(priv->irq, &a64fx_diag_handler_nmi, irq_flags, + "a64fx_diag_nmi", NULL); + if (ret) { + ret = request_irq(priv->irq, &a64fx_diag_handler_irq, + irq_flags, "a64fx_diag_irq", NULL); + if (ret) { + dev_err(dev, "cannot register IRQ %d\n", ret); + return ret; + } + enable_irq(priv->irq); + } else { + enable_nmi(priv->irq); + priv->has_nmi = true; + } + + a64fx_diag_interrupt_clear(priv); + a64fx_diag_interrupt_enable(priv); + + return 0; +} + +static int a64fx_diag_remove(struct platform_device *pdev) +{ + struct a64fx_diag_priv *priv = platform_get_drvdata(pdev); + + a64fx_diag_interrupt_disable(priv); + a64fx_diag_interrupt_clear(priv); + + if (priv->has_nmi) + free_nmi(priv->irq, NULL); + else + free_irq(priv->irq, NULL); + + return 0; +} + +static const struct acpi_device_id a64fx_diag_acpi_match[] = { + { "FUJI2007", 0 }, + { }, +}; +MODULE_DEVICE_TABLE(acpi, a64fx_diag_acpi_match); + + +static struct platform_driver a64fx_diag_driver = { + .driver = { + .name = "a64fx_diag_driver", + .acpi_match_table = ACPI_PTR(a64fx_diag_acpi_match), + }, + .probe = a64fx_diag_probe, + .remove = a64fx_diag_remove, +}; + +module_platform_driver(a64fx_diag_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Hitomi Hasegawa "); +MODULE_DESCRIPTION("A64FX diag driver");