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
  27 #include "ccp-dev.h"
  28
  29 static int ccp_get_irq(struct ccp_device *ccp)
  30 {
  31         struct device *dev = ccp->dev;
  32         struct platform_device *pdev = container_of(dev,
  33                                         struct platform_device, dev);
  34         int ret;
  35
  36         ret = platform_get_irq(pdev, 0);
  37         if (ret < 0)
  38                 return ret;
  39
  40         ccp->irq = ret;
  41         ret = request_irq(ccp->irq, ccp_irq_handler, 0, "ccp", dev);
  42         if (ret) {
  43                 dev_notice(dev, "unable to allocate IRQ (%d)\n", ret);
  44                 return ret;
  45         }
  46
  47         return 0;
  48 }
  49
  50 static int ccp_get_irqs(struct ccp_device *ccp)
  51 {
  52         struct device *dev = ccp->dev;
  53         int ret;
  54
  55         ret = ccp_get_irq(ccp);
  56         if (!ret)
  57                 return 0;
  58
  59         /* Couldn't get an interrupt */
  60         dev_notice(dev, "could not enable interrupts (%d)\n", ret);
  61
  62         return ret;
  63 }
  64
  65 static void ccp_free_irqs(struct ccp_device *ccp)
  66 {
  67         struct device *dev = ccp->dev;
  68
  69         free_irq(ccp->irq, dev);
  70 }
  71
  72 static struct resource *ccp_find_mmio_area(struct ccp_device *ccp)
  73 {
  74         struct device *dev = ccp->dev;
  75         struct platform_device *pdev = container_of(dev,
  76                                         struct platform_device, dev);
  77         struct resource *ior;
  78
  79         ior = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  80         if (ior && (resource_size(ior) >= 0x800))
  81                 return ior;
  82
  83         return NULL;
  84 }
  85
  86 static int ccp_platform_probe(struct platform_device *pdev)
  87 {
  88         struct ccp_device *ccp;
  89         struct device *dev = &pdev->dev;
  90         struct resource *ior;
  91         int ret;
  92
  93         ret = -ENOMEM;
  94         ccp = ccp_alloc_struct(dev);
  95         if (!ccp)
  96                 goto e_err;
  97
  98         ccp->dev_specific = NULL;
  99         ccp->get_irq = ccp_get_irqs;
 100         ccp->free_irq = ccp_free_irqs;
 101
 102         ior = ccp_find_mmio_area(ccp);
 103         ccp->io_map = devm_ioremap_resource(dev, ior);
 104         if (IS_ERR(ccp->io_map)) {
 105                 ret = PTR_ERR(ccp->io_map);
 106                 goto e_free;
 107         }
 108         ccp->io_regs = ccp->io_map;
 109
 110         if (!dev->dma_mask)
 111                 dev->dma_mask = &dev->coherent_dma_mask;
 112         *(dev->dma_mask) = DMA_BIT_MASK(48);
 113         dev->coherent_dma_mask = DMA_BIT_MASK(48);
 114
 115         if (of_property_read_bool(dev->of_node, "dma-coherent"))
 116                 ccp->axcache = CACHE_WB_NO_ALLOC;
 117         else
 118                 ccp->axcache = CACHE_NONE;
 119
 120         dev_set_drvdata(dev, ccp);
 121
 122         ret = ccp_init(ccp);
 123         if (ret)
 124                 goto e_free;
 125
 126         dev_notice(dev, "enabled\n");
 127
 128         return 0;
 129
 130 e_free:
 131         kfree(ccp);
 132
 133 e_err:
 134         dev_notice(dev, "initialization failed\n");
 135         return ret;
 136 }
 137
 138 static int ccp_platform_remove(struct platform_device *pdev)
 139 {
 140         struct device *dev = &pdev->dev;
 141         struct ccp_device *ccp = dev_get_drvdata(dev);
 142
 143         ccp_destroy(ccp);
 144
 145         kfree(ccp);
 146
 147         dev_notice(dev, "disabled\n");
 148
 149         return 0;
 150 }
 151
 152 #ifdef CONFIG_PM
 153 static int ccp_platform_suspend(struct platform_device *pdev,
 154                                 pm_message_t state)
 155 {
 156         struct device *dev = &pdev->dev;
 157         struct ccp_device *ccp = dev_get_drvdata(dev);
 158         unsigned long flags;
 159         unsigned int i;
 160
 161         spin_lock_irqsave(&ccp->cmd_lock, flags);
 162
 163         ccp->suspending = 1;
 164
 165         /* Wake all the queue kthreads to prepare for suspend */
 166         for (i = 0; i < ccp->cmd_q_count; i++)
 167                 wake_up_process(ccp->cmd_q[i].kthread);
 168
 169         spin_unlock_irqrestore(&ccp->cmd_lock, flags);
 170
 171         /* Wait for all queue kthreads to say they're done */
 172         while (!ccp_queues_suspended(ccp))
 173                 wait_event_interruptible(ccp->suspend_queue,
 174                                          ccp_queues_suspended(ccp));
 175
 176         return 0;
 177 }
 178
 179 static int ccp_platform_resume(struct platform_device *pdev)
 180 {
 181         struct device *dev = &pdev->dev;
 182         struct ccp_device *ccp = dev_get_drvdata(dev);
 183         unsigned long flags;
 184         unsigned int i;
 185
 186         spin_lock_irqsave(&ccp->cmd_lock, flags);
 187
 188         ccp->suspending = 0;
 189
 190         /* Wake up all the kthreads */
 191         for (i = 0; i < ccp->cmd_q_count; i++) {
 192                 ccp->cmd_q[i].suspended = 0;
 193                 wake_up_process(ccp->cmd_q[i].kthread);
 194         }
 195
 196         spin_unlock_irqrestore(&ccp->cmd_lock, flags);
 197
 198         return 0;
 199 }
 200 #endif
 201
 202 static const struct of_device_id ccp_platform_ids[] = {
 203         { .compatible = "amd,ccp-seattle-v1a" },
 204         { },
 205 };
 206
 207 static struct platform_driver ccp_platform_driver = {
 208         .driver = {
 209                 .name = "AMD Cryptographic Coprocessor",
 210                 .of_match_table = ccp_platform_ids,
 211         },
 212         .probe = ccp_platform_probe,
 213         .remove = ccp_platform_remove,
 214 #ifdef CONFIG_PM
 215         .suspend = ccp_platform_suspend,
 216         .resume = ccp_platform_resume,
 217 #endif
 218 };
 219
 220 int ccp_platform_init(void)
 221 {
 222         return platform_driver_register(&ccp_platform_driver);
 223 }
 224
 225 void ccp_platform_exit(void)
 226 {
 227         platform_driver_unregister(&ccp_platform_driver);
 228 }