drivers/dma/ptdma/ptdma-pci.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * AMD Passthru DMA device driver
   4  * -- Based on the CCP driver
   5  *
   6  * Copyright (C) 2016,2021 Advanced Micro Devices, Inc.
   7  *
   8  * Author: Sanjay R Mehta <sanju.mehta@amd.com>
   9  * Author: Tom Lendacky <thomas.lendacky@amd.com>
  10  * Author: Gary R Hook <gary.hook@amd.com>
  11  */
  12
  13 #include <linux/device.h>
  14 #include <linux/dma-mapping.h>
  15 #include <linux/delay.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/kernel.h>
  18 #include <linux/kthread.h>
  19 #include <linux/module.h>
  20 #include <linux/pci_ids.h>
  21 #include <linux/pci.h>
  22 #include <linux/spinlock.h>
  23
  24 #include "ptdma.h"
  25
  26 struct pt_msix {
  27         int msix_count;
  28         struct msix_entry msix_entry;
  29 };
  30
  31 /*
  32  * pt_alloc_struct - allocate and initialize the pt_device struct
  33  *
  34  * @dev: device struct of the PTDMA
  35  */
  36 static struct pt_device *pt_alloc_struct(struct device *dev)
  37 {
  38         struct pt_device *pt;
  39
  40         pt = devm_kzalloc(dev, sizeof(*pt), GFP_KERNEL);
  41
  42         if (!pt)
  43                 return NULL;
  44         pt->dev = dev;
  45
  46         INIT_LIST_HEAD(&pt->cmd);
  47
  48         return pt;
  49 }
  50
  51 static int pt_get_msix_irqs(struct pt_device *pt)
  52 {
  53         struct pt_msix *pt_msix = pt->pt_msix;
  54         struct device *dev = pt->dev;
  55         struct pci_dev *pdev = to_pci_dev(dev);
  56         int ret;
  57
  58         pt_msix->msix_entry.entry = 0;
  59
  60         ret = pci_enable_msix_range(pdev, &pt_msix->msix_entry, 1, 1);
  61         if (ret < 0)
  62                 return ret;
  63
  64         pt_msix->msix_count = ret;
  65
  66         pt->pt_irq = pt_msix->msix_entry.vector;
  67
  68         return 0;
  69 }
  70
  71 static int pt_get_msi_irq(struct pt_device *pt)
  72 {
  73         struct device *dev = pt->dev;
  74         struct pci_dev *pdev = to_pci_dev(dev);
  75         int ret;
  76
  77         ret = pci_enable_msi(pdev);
  78         if (ret)
  79                 return ret;
  80
  81         pt->pt_irq = pdev->irq;
  82
  83         return 0;
  84 }
  85
  86 static int pt_get_irqs(struct pt_device *pt)
  87 {
  88         struct device *dev = pt->dev;
  89         int ret;
  90
  91         ret = pt_get_msix_irqs(pt);
  92         if (!ret)
  93                 return 0;
  94
  95         /* Couldn't get MSI-X vectors, try MSI */
  96         dev_err(dev, "could not enable MSI-X (%d), trying MSI\n", ret);
  97         ret = pt_get_msi_irq(pt);
  98         if (!ret)
  99                 return 0;
 100
 101         /* Couldn't get MSI interrupt */
 102         dev_err(dev, "could not enable MSI (%d)\n", ret);
 103
 104         return ret;
 105 }
 106
 107 static void pt_free_irqs(struct pt_device *pt)
 108 {
 109         struct pt_msix *pt_msix = pt->pt_msix;
 110         struct device *dev = pt->dev;
 111         struct pci_dev *pdev = to_pci_dev(dev);
 112
 113         if (pt_msix->msix_count)
 114                 pci_disable_msix(pdev);
 115         else if (pt->pt_irq)
 116                 pci_disable_msi(pdev);
 117
 118         pt->pt_irq = 0;
 119 }
 120
 121 static int pt_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 122 {
 123         struct pt_device *pt;
 124         struct pt_msix *pt_msix;
 125         struct device *dev = &pdev->dev;
 126         void __iomem * const *iomap_table;
 127         int bar_mask;
 128         int ret = -ENOMEM;
 129
 130         pt = pt_alloc_struct(dev);
 131         if (!pt)
 132                 goto e_err;
 133
 134         pt_msix = devm_kzalloc(dev, sizeof(*pt_msix), GFP_KERNEL);
 135         if (!pt_msix)
 136                 goto e_err;
 137
 138         pt->pt_msix = pt_msix;
 139         pt->dev_vdata = (struct pt_dev_vdata *)id->driver_data;
 140         if (!pt->dev_vdata) {
 141                 ret = -ENODEV;
 142                 dev_err(dev, "missing driver data\n");
 143                 goto e_err;
 144         }
 145
 146         ret = pcim_enable_device(pdev);
 147         if (ret) {
 148                 dev_err(dev, "pcim_enable_device failed (%d)\n", ret);
 149                 goto e_err;
 150         }
 151
 152         bar_mask = pci_select_bars(pdev, IORESOURCE_MEM);
 153         ret = pcim_iomap_regions(pdev, bar_mask, "ptdma");
 154         if (ret) {
 155                 dev_err(dev, "pcim_iomap_regions failed (%d)\n", ret);
 156                 goto e_err;
 157         }
 158
 159         iomap_table = pcim_iomap_table(pdev);
 160         if (!iomap_table) {
 161                 dev_err(dev, "pcim_iomap_table failed\n");
 162                 ret = -ENOMEM;
 163                 goto e_err;
 164         }
 165
 166         pt->io_regs = iomap_table[pt->dev_vdata->bar];
 167         if (!pt->io_regs) {
 168                 dev_err(dev, "ioremap failed\n");
 169                 ret = -ENOMEM;
 170                 goto e_err;
 171         }
 172
 173         ret = pt_get_irqs(pt);
 174         if (ret)
 175                 goto e_err;
 176
 177         pci_set_master(pdev);
 178
 179         ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(48));
 180         if (ret) {
 181                 ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
 182                 if (ret) {
 183                         dev_err(dev, "dma_set_mask_and_coherent failed (%d)\n",
 184                                 ret);
 185                         goto e_err;
 186                 }
 187         }
 188
 189         dev_set_drvdata(dev, pt);
 190
 191         if (pt->dev_vdata)
 192                 ret = pt_core_init(pt);
 193
 194         if (ret)
 195                 goto e_err;
 196
 197         return 0;
 198
 199 e_err:
 200         dev_err(dev, "initialization failed ret = %d\n", ret);
 201
 202         return ret;
 203 }
 204
 205 static void pt_pci_remove(struct pci_dev *pdev)
 206 {
 207         struct device *dev = &pdev->dev;
 208         struct pt_device *pt = dev_get_drvdata(dev);
 209
 210         if (!pt)
 211                 return;
 212
 213         if (pt->dev_vdata)
 214                 pt_core_destroy(pt);
 215
 216         pt_free_irqs(pt);
 217 }
 218
 219 static const struct pt_dev_vdata dev_vdata[] = {
 220         {
 221                 .bar = 2,
 222         },
 223 };
 224
 225 static const struct pci_device_id pt_pci_table[] = {
 226         { PCI_VDEVICE(AMD, 0x1498), (kernel_ulong_t)&dev_vdata[0] },
 227         /* Last entry must be zero */
 228         { 0, }
 229 };
 230 MODULE_DEVICE_TABLE(pci, pt_pci_table);
 231
 232 static struct pci_driver pt_pci_driver = {
 233         .name = "ptdma",
 234         .id_table = pt_pci_table,
 235         .probe = pt_pci_probe,
 236         .remove = pt_pci_remove,
 237 };
 238
 239 module_pci_driver(pt_pci_driver);
 240
 241 MODULE_AUTHOR("Sanjay R Mehta <sanju.mehta@amd.com>");
 242 MODULE_LICENSE("GPL");
 243 MODULE_DESCRIPTION("AMD PassThru DMA driver");