drivers/staging/xillybus/xillybus_pcie.c

   1 /*
   2  * linux/drivers/misc/xillybus_pcie.c
   3  *
   4  * Copyright 2011 Xillybus Ltd, http://xillybus.com
   5  *
   6  * Driver for the Xillybus FPGA/host framework using PCI Express.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the smems of the GNU General Public License as published by
  10  * the Free Software Foundation; version 2 of the License.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/pci.h>
  15 #include <linux/pci-aspm.h>
  16 #include <linux/slab.h>
  17 #include "xillybus.h"
  18
  19 MODULE_DESCRIPTION("Xillybus driver for PCIe");
  20 MODULE_AUTHOR("Eli Billauer, Xillybus Ltd.");
  21 MODULE_VERSION("1.06");
  22 MODULE_ALIAS("xillybus_pcie");
  23 MODULE_LICENSE("GPL v2");
  24
  25 #define PCI_DEVICE_ID_XILLYBUS          0xebeb
  26
  27 #define PCI_VENDOR_ID_ALTERA            0x1172
  28 #define PCI_VENDOR_ID_ACTEL             0x11aa
  29 #define PCI_VENDOR_ID_LATTICE           0x1204
  30
  31 static const char xillyname[] = "xillybus_pcie";
  32
  33 static DEFINE_PCI_DEVICE_TABLE(xillyids) = {
  34         {PCI_DEVICE(PCI_VENDOR_ID_XILINX, PCI_DEVICE_ID_XILLYBUS)},
  35         {PCI_DEVICE(PCI_VENDOR_ID_ALTERA, PCI_DEVICE_ID_XILLYBUS)},
  36         {PCI_DEVICE(PCI_VENDOR_ID_ACTEL, PCI_DEVICE_ID_XILLYBUS)},
  37         {PCI_DEVICE(PCI_VENDOR_ID_LATTICE, PCI_DEVICE_ID_XILLYBUS)},
  38         { /* End: all zeroes */ }
  39 };
  40
  41 static int xilly_pci_direction(int direction)
  42 {
  43         switch (direction) {
  44         case DMA_TO_DEVICE:
  45                 return PCI_DMA_TODEVICE;
  46         case DMA_FROM_DEVICE:
  47                 return PCI_DMA_FROMDEVICE;
  48         default:
  49                 return PCI_DMA_BIDIRECTIONAL;
  50         }
  51 }
  52
  53 static void xilly_dma_sync_single_for_cpu_pci(struct xilly_endpoint *ep,
  54                                               dma_addr_t dma_handle,
  55                                               size_t size,
  56                                               int direction)
  57 {
  58         pci_dma_sync_single_for_cpu(ep->pdev,
  59                                     dma_handle,
  60                                     size,
  61                                     xilly_pci_direction(direction));
  62 }
  63
  64 static void xilly_dma_sync_single_for_device_pci(struct xilly_endpoint *ep,
  65                                                  dma_addr_t dma_handle,
  66                                                  size_t size,
  67                                                  int direction)
  68 {
  69         pci_dma_sync_single_for_device(ep->pdev,
  70                                        dma_handle,
  71                                        size,
  72                                        xilly_pci_direction(direction));
  73 }
  74
  75 /*
  76  * Map either through the PCI DMA mapper or the non_PCI one. Behind the
  77  * scenes exactly the same functions are called with the same parameters,
  78  * but that can change.
  79  */
  80
  81 static dma_addr_t xilly_map_single_pci(struct xilly_cleanup *mem,
  82                                        struct xilly_endpoint *ep,
  83                                        void *ptr,
  84                                        size_t size,
  85                                        int direction
  86         )
  87 {
  88
  89         dma_addr_t addr = 0;
  90         struct xilly_dma *this;
  91         int pci_direction;
  92
  93         this = kmalloc(sizeof(struct xilly_dma), GFP_KERNEL);
  94         if (!this)
  95                 return 0;
  96
  97         pci_direction = xilly_pci_direction(direction);
  98         addr = pci_map_single(ep->pdev, ptr, size, pci_direction);
  99         this->direction = pci_direction;
 100
 101         if (pci_dma_mapping_error(ep->pdev, addr)) {
 102                 kfree(this);
 103                 return 0;
 104         }
 105
 106         this->dma_addr = addr;
 107         this->pdev = ep->pdev;
 108         this->size = size;
 109
 110         list_add_tail(&this->node, &mem->to_unmap);
 111
 112         return addr;
 113 }
 114
 115 static void xilly_unmap_single_pci(struct xilly_dma *entry)
 116 {
 117         pci_unmap_single(entry->pdev,
 118                          entry->dma_addr,
 119                          entry->size,
 120                          entry->direction);
 121 }
 122
 123 static struct xilly_endpoint_hardware pci_hw = {
 124         .owner = THIS_MODULE,
 125         .hw_sync_sgl_for_cpu = xilly_dma_sync_single_for_cpu_pci,
 126         .hw_sync_sgl_for_device = xilly_dma_sync_single_for_device_pci,
 127         .map_single = xilly_map_single_pci,
 128         .unmap_single = xilly_unmap_single_pci
 129 };
 130
 131 static int xilly_probe(struct pci_dev *pdev,
 132                                  const struct pci_device_id *ent)
 133 {
 134         struct xilly_endpoint *endpoint;
 135         int rc = 0;
 136
 137         endpoint = xillybus_init_endpoint(pdev, &pdev->dev, &pci_hw);
 138
 139         if (!endpoint)
 140                 return -ENOMEM;
 141
 142         pci_set_drvdata(pdev, endpoint);
 143
 144         rc = pci_enable_device(pdev);
 145
 146         /* L0s has caused packet drops. No power saving, thank you. */
 147
 148         pci_disable_link_state(pdev, PCIE_LINK_STATE_L0S);
 149
 150         if (rc) {
 151                 dev_err(endpoint->dev,
 152                         "pci_enable_device() failed. Aborting.\n");
 153                 goto no_enable;
 154         }
 155
 156         if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM)) {
 157                 dev_err(endpoint->dev,
 158                         "Incorrect BAR configuration. Aborting.\n");
 159                 rc = -ENODEV;
 160                 goto bad_bar;
 161         }
 162
 163         rc = pci_request_regions(pdev, xillyname);
 164         if (rc) {
 165                 dev_err(endpoint->dev,
 166                         "pci_request_regions() failed. Aborting.\n");
 167                 goto failed_request_regions;
 168         }
 169
 170         endpoint->registers = pci_iomap(pdev, 0, 128);
 171
 172         if (!endpoint->registers) {
 173                 dev_err(endpoint->dev, "Failed to map BAR 0. Aborting.\n");
 174                 goto failed_iomap0;
 175         }
 176
 177         pci_set_master(pdev);
 178
 179         /* Set up a single MSI interrupt */
 180         if (pci_enable_msi(pdev)) {
 181                 dev_err(endpoint->dev,
 182                         "Failed to enable MSI interrupts. Aborting.\n");
 183                 rc = -ENODEV;
 184                 goto failed_enable_msi;
 185         }
 186         rc = request_irq(pdev->irq, xillybus_isr, 0, xillyname, endpoint);
 187
 188         if (rc) {
 189                 dev_err(endpoint->dev,
 190                         "Failed to register MSI handler. Aborting.\n");
 191                 rc = -ENODEV;
 192                 goto failed_register_msi;
 193         }
 194
 195         /*
 196          * In theory, an attempt to set the DMA mask to 64 and dma_using_dac=1
 197          * is the right thing. But some unclever PCIe drivers report it's OK
 198          * when the hardware drops those 64-bit PCIe packets. So trust
 199          * nobody and use 32 bits DMA addressing in any case.
 200          */
 201
 202         if (!pci_set_dma_mask(pdev, DMA_BIT_MASK(32)))
 203                 endpoint->dma_using_dac = 0;
 204         else {
 205                 dev_err(endpoint->dev, "Failed to set DMA mask. Aborting.\n");
 206                 rc = -ENODEV;
 207                 goto failed_dmamask;
 208         }
 209
 210         rc = xillybus_endpoint_discovery(endpoint);
 211
 212         if (!rc)
 213                 return 0;
 214
 215 failed_dmamask:
 216         free_irq(pdev->irq, endpoint);
 217 failed_register_msi:
 218         pci_disable_msi(pdev);
 219 failed_enable_msi:
 220         /* pci_clear_master(pdev); Nobody else seems to do this */
 221         pci_iounmap(pdev, endpoint->registers);
 222 failed_iomap0:
 223         pci_release_regions(pdev);
 224 failed_request_regions:
 225 bad_bar:
 226         pci_disable_device(pdev);
 227 no_enable:
 228         xillybus_do_cleanup(&endpoint->cleanup, endpoint);
 229
 230         kfree(endpoint);
 231         return rc;
 232 }
 233
 234 static void xilly_remove(struct pci_dev *pdev)
 235 {
 236         struct xilly_endpoint *endpoint = pci_get_drvdata(pdev);
 237
 238         xillybus_endpoint_remove(endpoint);
 239
 240         free_irq(pdev->irq, endpoint);
 241
 242         pci_disable_msi(pdev);
 243         pci_iounmap(pdev, endpoint->registers);
 244         pci_release_regions(pdev);
 245         pci_disable_device(pdev);
 246
 247         xillybus_do_cleanup(&endpoint->cleanup, endpoint);
 248
 249         kfree(endpoint);
 250 }
 251
 252 MODULE_DEVICE_TABLE(pci, xillyids);
 253
 254 static struct pci_driver xillybus_driver = {
 255         .name = xillyname,
 256         .id_table = xillyids,
 257         .probe = xilly_probe,
 258         .remove = xilly_remove,
 259 };
 260
 261 module_pci_driver(xillybus_driver);