kernel/drivers/crypto/ccp/ccp-platform.c

   1 /*
   2  * AMD Cryptographic Coprocessor (CCP) driver
   3  *
   4  * Copyright (C) 2014 Advanced Micro Devices, Inc.
   5  *
   6  * Author: Tom Lendacky <thomas.lendacky@amd.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/kernel.h>
  15 #include <linux/device.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/ioport.h>
  18 #include <linux/dma-mapping.h>
  19 #include <linux/kthread.h>
  20 #include <linux/sched.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/spinlock.h>
  23 #include <linux/delay.h>
  24 #include <linux/ccp.h>
  25 #include <linux/of.h>
  26 #include <linux/of_address.h>
  27 #include <linux/acpi.h>
  28
  29 #include "ccp-dev.h"
  30
  31 struct ccp_platform {
  32         int use_acpi;
  33         int coherent;
  34 };
  35
  36 static int ccp_get_irq(struct ccp_device *ccp)
  37 {
  38         struct device *dev = ccp->dev;
  39         struct platform_device *pdev = container_of(dev,
  40                                         struct platform_device, dev);
  41         int ret;
  42
  43         ret = platform_get_irq(pdev, 0);
  44         if (ret < 0)
  45                 return ret;
  46
  47         ccp->irq = ret;
  48         ret = request_irq(ccp->irq, ccp_irq_handler, 0, "ccp", dev);
  49         if (ret) {
  50                 dev_notice(dev, "unable to allocate IRQ (%d)\n", ret);
  51                 return ret;
  52         }
  53
  54         return 0;
  55 }
  56
  57 static int ccp_get_irqs(struct ccp_device *ccp)
  58 {
  59         struct device *dev = ccp->dev;
  60         int ret;
  61
  62         ret = ccp_get_irq(ccp);
  63         if (!ret)
  64                 return 0;
  65
  66         /* Couldn't get an interrupt */
  67         dev_notice(dev, "could not enable interrupts (%d)\n", ret);
  68
  69         return ret;
  70 }
  71
  72 static void ccp_free_irqs(struct ccp_device *ccp)
  73 {
  74         struct device *dev = ccp->dev;
  75
  76         free_irq(ccp->irq, dev);
  77 }
  78
  79 static struct resource *ccp_find_mmio_area(struct ccp_device *ccp)
  80 {
  81         struct device *dev = ccp->dev;
  82         struct platform_device *pdev = container_of(dev,
  83                                         struct platform_device, dev);
  84         struct resource *ior;
  85
  86         ior = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  87         if (ior && (resource_size(ior) >= 0x800))
  88                 return ior;
  89
  90         return NULL;
  91 }
  92
  93 #ifdef CONFIG_ACPI
  94 static int ccp_acpi_support(struct ccp_device *ccp)
  95 {
  96         struct ccp_platform *ccp_platform = ccp->dev_specific;
  97         struct acpi_device *adev = ACPI_COMPANION(ccp->dev);
  98         acpi_handle handle;
  99         acpi_status status;
 100         unsigned long long data;
 101         int cca;
 102
 103         /* Retrieve the device cache coherency value */
 104         handle = adev->handle;
 105         do {
 106                 status = acpi_evaluate_integer(handle, "_CCA", NULL, &data);
 107                 if (!ACPI_FAILURE(status)) {
 108                         cca = data;
 109                         break;
 110                 }
 111         } while (!ACPI_FAILURE(status));
 112
 113         if (ACPI_FAILURE(status)) {
 114                 dev_err(ccp->dev, "error obtaining acpi coherency value\n");
 115                 return -EINVAL;
 116         }
 117
 118         ccp_platform->coherent = !!cca;
 119
 120         return 0;
 121 }
 122 #else   /* CONFIG_ACPI */
 123 static int ccp_acpi_support(struct ccp_device *ccp)
 124 {
 125         return -EINVAL;
 126 }
 127 #endif
 128
 129 #ifdef CONFIG_OF
 130 static int ccp_of_support(struct ccp_device *ccp)
 131 {
 132         struct ccp_platform *ccp_platform = ccp->dev_specific;
 133
 134         ccp_platform->coherent = of_dma_is_coherent(ccp->dev->of_node);
 135
 136         return 0;
 137 }
 138 #else
 139 static int ccp_of_support(struct ccp_device *ccp)
 140 {
 141         return -EINVAL;
 142 }
 143 #endif
 144
 145 static int ccp_platform_probe(struct platform_device *pdev)
 146 {
 147         struct ccp_device *ccp;
 148         struct ccp_platform *ccp_platform;
 149         struct device *dev = &pdev->dev;
 150         struct acpi_device *adev = ACPI_COMPANION(dev);
 151         struct resource *ior;
 152         int ret;
 153
 154         ret = -ENOMEM;
 155         ccp = ccp_alloc_struct(dev);
 156         if (!ccp)
 157                 goto e_err;
 158
 159         ccp_platform = devm_kzalloc(dev, sizeof(*ccp_platform), GFP_KERNEL);
 160         if (!ccp_platform)
 161                 goto e_err;
 162
 163         ccp->dev_specific = ccp_platform;
 164         ccp->get_irq = ccp_get_irqs;
 165         ccp->free_irq = ccp_free_irqs;
 166
 167         ccp_platform->use_acpi = (!adev || acpi_disabled) ? 0 : 1;
 168
 169         ior = ccp_find_mmio_area(ccp);
 170         ccp->io_map = devm_ioremap_resource(dev, ior);
 171         if (IS_ERR(ccp->io_map)) {
 172                 ret = PTR_ERR(ccp->io_map);
 173                 goto e_err;
 174         }
 175         ccp->io_regs = ccp->io_map;
 176
 177         if (!dev->dma_mask)
 178                 dev->dma_mask = &dev->coherent_dma_mask;
 179         ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(48));
 180         if (ret) {
 181                 dev_err(dev, "dma_set_mask_and_coherent failed (%d)\n", ret);
 182                 goto e_err;
 183         }
 184
 185         if (ccp_platform->use_acpi)
 186                 ret = ccp_acpi_support(ccp);
 187         else
 188                 ret = ccp_of_support(ccp);
 189         if (ret)
 190                 goto e_err;
 191
 192         if (ccp_platform->coherent)
 193                 ccp->axcache = CACHE_WB_NO_ALLOC;
 194         else
 195                 ccp->axcache = CACHE_NONE;
 196
 197         dev_set_drvdata(dev, ccp);
 198
 199         ret = ccp_init(ccp);
 200         if (ret)
 201                 goto e_err;
 202
 203         dev_notice(dev, "enabled\n");
 204
 205         return 0;
 206
 207 e_err:
 208         dev_notice(dev, "initialization failed\n");
 209         return ret;
 210 }
 211
 212 static int ccp_platform_remove(struct platform_device *pdev)
 213 {
 214         struct device *dev = &pdev->dev;
 215         struct ccp_device *ccp = dev_get_drvdata(dev);
 216
 217         ccp_destroy(ccp);
 218
 219         dev_notice(dev, "disabled\n");
 220
 221         return 0;
 222 }
 223
 224 #ifdef CONFIG_PM
 225 static int ccp_platform_suspend(struct platform_device *pdev,
 226                                 pm_message_t state)
 227 {
 228         struct device *dev = &pdev->dev;
 229         struct ccp_device *ccp = dev_get_drvdata(dev);
 230         unsigned long flags;
 231         unsigned int i;
 232
 233         spin_lock_irqsave(&ccp->cmd_lock, flags);
 234
 235         ccp->suspending = 1;
 236
 237         /* Wake all the queue kthreads to prepare for suspend */
 238         for (i = 0; i < ccp->cmd_q_count; i++)
 239                 wake_up_process(ccp->cmd_q[i].kthread);
 240
 241         spin_unlock_irqrestore(&ccp->cmd_lock, flags);
 242
 243         /* Wait for all queue kthreads to say they're done */
 244         while (!ccp_queues_suspended(ccp))
 245                 wait_event_interruptible(ccp->suspend_queue,
 246                                          ccp_queues_suspended(ccp));
 247
 248         return 0;
 249 }
 250
 251 static int ccp_platform_resume(struct platform_device *pdev)
 252 {
 253         struct device *dev = &pdev->dev;
 254         struct ccp_device *ccp = dev_get_drvdata(dev);
 255         unsigned long flags;
 256         unsigned int i;
 257
 258         spin_lock_irqsave(&ccp->cmd_lock, flags);
 259
 260         ccp->suspending = 0;
 261
 262         /* Wake up all the kthreads */
 263         for (i = 0; i < ccp->cmd_q_count; i++) {
 264                 ccp->cmd_q[i].suspended = 0;
 265                 wake_up_process(ccp->cmd_q[i].kthread);
 266         }
 267
 268         spin_unlock_irqrestore(&ccp->cmd_lock, flags);
 269
 270         return 0;
 271 }
 272 #endif
 273
 274 #ifdef CONFIG_ACPI
 275 static const struct acpi_device_id ccp_acpi_match[] = {
 276         { "AMDI0C00", 0 },
 277         { },
 278 };
 279 #endif
 280
 281 #ifdef CONFIG_OF
 282 static const struct of_device_id ccp_of_match[] = {
 283         { .compatible = "amd,ccp-seattle-v1a" },
 284         { },
 285 };
 286 #endif
 287
 288 static struct platform_driver ccp_platform_driver = {
 289         .driver = {
 290                 .name = "AMD Cryptographic Coprocessor",
 291 #ifdef CONFIG_ACPI
 292                 .acpi_match_table = ccp_acpi_match,
 293 #endif
 294 #ifdef CONFIG_OF
 295                 .of_match_table = ccp_of_match,
 296 #endif
 297         },
 298         .probe = ccp_platform_probe,
 299         .remove = ccp_platform_remove,
 300 #ifdef CONFIG_PM
 301         .suspend = ccp_platform_suspend,
 302         .resume = ccp_platform_resume,
 303 #endif
 304 };
 305
 306 int ccp_platform_init(void)
 307 {
 308         return platform_driver_register(&ccp_platform_driver);
 309 }
 310
 311 void ccp_platform_exit(void)
 312 {
 313         platform_driver_unregister(&ccp_platform_driver);
 314 }