diff options
Diffstat (limited to 'drivers/acpi/arm64/agdi.c')
| -rw-r--r-- | drivers/acpi/arm64/agdi.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/drivers/acpi/arm64/agdi.c b/drivers/acpi/arm64/agdi.c new file mode 100644 index 000000000..0c2d9d6c1 --- /dev/null +++ b/drivers/acpi/arm64/agdi.c @@ -0,0 +1,205 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file implements handling of + * Arm Generic Diagnostic Dump and Reset Interface table (AGDI) + * + * Copyright (c) 2022, Ampere Computing LLC + */ + +#define pr_fmt(fmt) "ACPI: AGDI: " fmt + +#include <linux/acpi.h> +#include <linux/arm_sdei.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include "init.h" + +struct agdi_data { + unsigned char flags; /* AGDI Signaling Mode */ + int sdei_event; + unsigned int gsiv; + bool use_nmi; + int irq; +}; + +static int agdi_sdei_handler(u32 sdei_event, struct pt_regs *regs, void *arg) +{ + nmi_panic(regs, "Arm Generic Diagnostic Dump and Reset SDEI event issued"); + return 0; +} + +static int agdi_sdei_probe(struct platform_device *pdev, + struct agdi_data *adata) +{ + int err; + + err = sdei_event_register(adata->sdei_event, agdi_sdei_handler, pdev); + if (err) { + dev_err(&pdev->dev, "Failed to register for SDEI event %d\n", + adata->sdei_event); + return err; + } + + err = sdei_event_enable(adata->sdei_event); + if (err) { + sdei_event_unregister(adata->sdei_event); + dev_err(&pdev->dev, "Failed to enable event %d\n", + adata->sdei_event); + return err; + } + + return 0; +} + +static irqreturn_t agdi_interrupt_handler_nmi(int irq, void *dev_id) +{ + nmi_panic(NULL, "Arm Generic Diagnostic Dump and Reset NMI Interrupt event issued\n"); + return IRQ_HANDLED; +} + +static irqreturn_t agdi_interrupt_handler_irq(int irq, void *dev_id) +{ + panic("Arm Generic Diagnostic Dump and Reset Interrupt event issued\n"); + return IRQ_HANDLED; +} + +static int agdi_interrupt_probe(struct platform_device *pdev, + struct agdi_data *adata) +{ + unsigned long irq_flags; + int ret; + int irq; + + irq = acpi_register_gsi(NULL, adata->gsiv, ACPI_EDGE_SENSITIVE, ACPI_ACTIVE_HIGH); + if (irq < 0) { + dev_err(&pdev->dev, "cannot register GSI#%d (%d)\n", adata->gsiv, irq); + return irq; + } + + irq_flags = IRQF_PERCPU | IRQF_NOBALANCING | IRQF_NO_AUTOEN | + IRQF_NO_THREAD; + /* try NMI first */ + ret = request_nmi(irq, &agdi_interrupt_handler_nmi, irq_flags, + "agdi_interrupt_nmi", NULL); + if (!ret) { + enable_nmi(irq); + adata->irq = irq; + adata->use_nmi = true; + return 0; + } + + /* Then try normal interrupt */ + ret = request_irq(irq, &agdi_interrupt_handler_irq, + irq_flags, "agdi_interrupt_irq", NULL); + if (ret) { + dev_err(&pdev->dev, "cannot register IRQ %d\n", ret); + acpi_unregister_gsi(adata->gsiv); + return ret; + } + enable_irq(irq); + adata->irq = irq; + + return 0; +} + +static int agdi_probe(struct platform_device *pdev) +{ + struct agdi_data *adata = dev_get_platdata(&pdev->dev); + + if (!adata) + return -EINVAL; + + if (adata->flags & ACPI_AGDI_SIGNALING_MODE) + return agdi_interrupt_probe(pdev, adata); + else + return agdi_sdei_probe(pdev, adata); +} + +static void agdi_sdei_remove(struct platform_device *pdev, + struct agdi_data *adata) +{ + int err, i; + + err = sdei_event_disable(adata->sdei_event); + if (err) { + dev_err(&pdev->dev, "Failed to disable sdei-event #%d (%pe)\n", + adata->sdei_event, ERR_PTR(err)); + return; + } + + for (i = 0; i < 3; i++) { + err = sdei_event_unregister(adata->sdei_event); + if (err != -EINPROGRESS) + break; + + schedule(); + } + + if (err) + dev_err(&pdev->dev, "Failed to unregister sdei-event #%d (%pe)\n", + adata->sdei_event, ERR_PTR(err)); +} + +static void agdi_interrupt_remove(struct platform_device *pdev, + struct agdi_data *adata) +{ + if (adata->irq == -1) + return; + + if (adata->use_nmi) + free_nmi(adata->irq, NULL); + else + free_irq(adata->irq, NULL); + + acpi_unregister_gsi(adata->gsiv); +} + +static void agdi_remove(struct platform_device *pdev) +{ + struct agdi_data *adata = dev_get_platdata(&pdev->dev); + + if (adata->flags & ACPI_AGDI_SIGNALING_MODE) + agdi_interrupt_remove(pdev, adata); + else + agdi_sdei_remove(pdev, adata); +} + +static struct platform_driver agdi_driver = { + .driver = { + .name = "agdi", + }, + .probe = agdi_probe, + .remove = agdi_remove, +}; + +void __init acpi_agdi_init(void) +{ + struct acpi_table_agdi *agdi_table; + struct agdi_data pdata = { 0 }; + struct platform_device *pdev; + acpi_status status; + + status = acpi_get_table(ACPI_SIG_AGDI, 0, + (struct acpi_table_header **) &agdi_table); + if (ACPI_FAILURE(status)) + return; + + if (agdi_table->flags & ACPI_AGDI_SIGNALING_MODE) + pdata.gsiv = agdi_table->gsiv; + else + pdata.sdei_event = agdi_table->sdei_event; + + pdata.irq = -1; + pdata.flags = agdi_table->flags; + + pdev = platform_device_register_data(NULL, "agdi", 0, &pdata, sizeof(pdata)); + if (IS_ERR(pdev)) + goto err_put_table; + + if (platform_driver_register(&agdi_driver)) + platform_device_unregister(pdev); + +err_put_table: + acpi_put_table((struct acpi_table_header *)agdi_table); +} |