1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * This file implements handling of 4 * Arm Generic Diagnostic Dump and Reset Interface table (AGDI) 5 * 6 * Copyright (c) 2022, Ampere Computing LLC 7 */ 8 9 #define pr_fmt(fmt) "ACPI: AGDI: " fmt 10 11 #include <linux/acpi.h> 12 #include <linux/arm_sdei.h> 13 #include <linux/io.h> 14 #include <linux/kernel.h> 15 #include <linux/platform_device.h> 16 #include "init.h" 17 18 struct agdi_data { 19 int sdei_event; 20 }; 21 22 static int agdi_sdei_handler(u32 sdei_event, struct pt_regs *regs, void *arg) 23 { 24 nmi_panic(regs, "Arm Generic Diagnostic Dump and Reset SDEI event issued"); 25 return 0; 26 } 27 28 static int agdi_sdei_probe(struct platform_device *pdev, 29 struct agdi_data *adata) 30 { 31 int err; 32 33 err = sdei_event_register(adata->sdei_event, agdi_sdei_handler, pdev); 34 if (err) { 35 dev_err(&pdev->dev, "Failed to register for SDEI event %d", 36 adata->sdei_event); 37 return err; 38 } 39 40 err = sdei_event_enable(adata->sdei_event); 41 if (err) { 42 sdei_event_unregister(adata->sdei_event); 43 dev_err(&pdev->dev, "Failed to enable event %d\n", 44 adata->sdei_event); 45 return err; 46 } 47 48 return 0; 49 } 50 51 static int agdi_probe(struct platform_device *pdev) 52 { 53 struct agdi_data *adata = dev_get_platdata(&pdev->dev); 54 55 if (!adata) 56 return -EINVAL; 57 58 return agdi_sdei_probe(pdev, adata); 59 } 60 61 static int agdi_remove(struct platform_device *pdev) 62 { 63 struct agdi_data *adata = dev_get_platdata(&pdev->dev); 64 int err, i; 65 66 err = sdei_event_disable(adata->sdei_event); 67 if (err) { 68 dev_err(&pdev->dev, "Failed to disable sdei-event #%d (%pe)\n", 69 adata->sdei_event, ERR_PTR(err)); 70 return 0; 71 } 72 73 for (i = 0; i < 3; i++) { 74 err = sdei_event_unregister(adata->sdei_event); 75 if (err != -EINPROGRESS) 76 break; 77 78 schedule(); 79 } 80 81 if (err) 82 dev_err(&pdev->dev, "Failed to unregister sdei-event #%d (%pe)\n", 83 adata->sdei_event, ERR_PTR(err)); 84 85 return 0; 86 } 87 88 static struct platform_driver agdi_driver = { 89 .driver = { 90 .name = "agdi", 91 }, 92 .probe = agdi_probe, 93 .remove = agdi_remove, 94 }; 95 96 void __init acpi_agdi_init(void) 97 { 98 struct acpi_table_agdi *agdi_table; 99 struct agdi_data pdata; 100 struct platform_device *pdev; 101 acpi_status status; 102 103 status = acpi_get_table(ACPI_SIG_AGDI, 0, 104 (struct acpi_table_header **) &agdi_table); 105 if (ACPI_FAILURE(status)) 106 return; 107 108 if (agdi_table->flags & ACPI_AGDI_SIGNALING_MODE) { 109 pr_warn("Interrupt signaling is not supported"); 110 goto err_put_table; 111 } 112 113 pdata.sdei_event = agdi_table->sdei_event; 114 115 pdev = platform_device_register_data(NULL, "agdi", 0, &pdata, sizeof(pdata)); 116 if (IS_ERR(pdev)) 117 goto err_put_table; 118 119 if (platform_driver_register(&agdi_driver)) 120 platform_device_unregister(pdev); 121 122 err_put_table: 123 acpi_put_table((struct acpi_table_header *)agdi_table); 124 } 125