1 /* 2 * Copyright 2016-17 IBM Corp. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 */ 9 10 #define pr_fmt(fmt) "vas: " fmt 11 12 #include <linux/module.h> 13 #include <linux/kernel.h> 14 #include <linux/export.h> 15 #include <linux/types.h> 16 #include <linux/slab.h> 17 #include <linux/platform_device.h> 18 #include <linux/of_platform.h> 19 #include <linux/of_address.h> 20 #include <linux/of.h> 21 #include <asm/prom.h> 22 23 #include "vas.h" 24 25 DEFINE_MUTEX(vas_mutex); 26 static LIST_HEAD(vas_instances); 27 28 static DEFINE_PER_CPU(int, cpu_vas_id); 29 30 static int init_vas_instance(struct platform_device *pdev) 31 { 32 int rc, cpu, vasid; 33 struct resource *res; 34 struct vas_instance *vinst; 35 struct device_node *dn = pdev->dev.of_node; 36 37 rc = of_property_read_u32(dn, "ibm,vas-id", &vasid); 38 if (rc) { 39 pr_err("No ibm,vas-id property for %s?\n", pdev->name); 40 return -ENODEV; 41 } 42 43 if (pdev->num_resources != 4) { 44 pr_err("Unexpected DT configuration for [%s, %d]\n", 45 pdev->name, vasid); 46 return -ENODEV; 47 } 48 49 vinst = kzalloc(sizeof(*vinst), GFP_KERNEL); 50 if (!vinst) 51 return -ENOMEM; 52 53 INIT_LIST_HEAD(&vinst->node); 54 ida_init(&vinst->ida); 55 mutex_init(&vinst->mutex); 56 vinst->vas_id = vasid; 57 vinst->pdev = pdev; 58 59 res = &pdev->resource[0]; 60 vinst->hvwc_bar_start = res->start; 61 62 res = &pdev->resource[1]; 63 vinst->uwc_bar_start = res->start; 64 65 res = &pdev->resource[2]; 66 vinst->paste_base_addr = res->start; 67 68 res = &pdev->resource[3]; 69 if (res->end > 62) { 70 pr_err("Bad 'paste_win_id_shift' in DT, %llx\n", res->end); 71 goto free_vinst; 72 } 73 74 vinst->paste_win_id_shift = 63 - res->end; 75 76 pr_devel("Initialized instance [%s, %d], paste_base 0x%llx, " 77 "paste_win_id_shift 0x%llx\n", pdev->name, vasid, 78 vinst->paste_base_addr, vinst->paste_win_id_shift); 79 80 for_each_possible_cpu(cpu) { 81 if (cpu_to_chip_id(cpu) == of_get_ibm_chip_id(dn)) 82 per_cpu(cpu_vas_id, cpu) = vasid; 83 } 84 85 mutex_lock(&vas_mutex); 86 list_add(&vinst->node, &vas_instances); 87 mutex_unlock(&vas_mutex); 88 89 vas_instance_init_dbgdir(vinst); 90 91 dev_set_drvdata(&pdev->dev, vinst); 92 93 return 0; 94 95 free_vinst: 96 kfree(vinst); 97 return -ENODEV; 98 99 } 100 101 /* 102 * Although this is read/used multiple times, it is written to only 103 * during initialization. 104 */ 105 struct vas_instance *find_vas_instance(int vasid) 106 { 107 struct list_head *ent; 108 struct vas_instance *vinst; 109 110 mutex_lock(&vas_mutex); 111 112 if (vasid == -1) 113 vasid = per_cpu(cpu_vas_id, smp_processor_id()); 114 115 list_for_each(ent, &vas_instances) { 116 vinst = list_entry(ent, struct vas_instance, node); 117 if (vinst->vas_id == vasid) { 118 mutex_unlock(&vas_mutex); 119 return vinst; 120 } 121 } 122 mutex_unlock(&vas_mutex); 123 124 pr_devel("Instance %d not found\n", vasid); 125 return NULL; 126 } 127 128 int chip_to_vas_id(int chipid) 129 { 130 int cpu; 131 132 for_each_possible_cpu(cpu) { 133 if (cpu_to_chip_id(cpu) == chipid) 134 return per_cpu(cpu_vas_id, cpu); 135 } 136 return -1; 137 } 138 EXPORT_SYMBOL(chip_to_vas_id); 139 140 static int vas_probe(struct platform_device *pdev) 141 { 142 return init_vas_instance(pdev); 143 } 144 145 static const struct of_device_id powernv_vas_match[] = { 146 { .compatible = "ibm,vas",}, 147 {}, 148 }; 149 150 static struct platform_driver vas_driver = { 151 .driver = { 152 .name = "vas", 153 .of_match_table = powernv_vas_match, 154 }, 155 .probe = vas_probe, 156 }; 157 158 static int __init vas_init(void) 159 { 160 int found = 0; 161 struct device_node *dn; 162 163 platform_driver_register(&vas_driver); 164 165 for_each_compatible_node(dn, NULL, "ibm,vas") { 166 of_platform_device_create(dn, NULL, NULL); 167 found++; 168 } 169 170 if (!found) { 171 platform_driver_unregister(&vas_driver); 172 return -ENODEV; 173 } 174 175 pr_devel("Found %d instances\n", found); 176 177 return 0; 178 } 179 device_initcall(vas_init); 180