drivers/char/xillybus/xillybus_pcie.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * linux/drivers/misc/xillybus_pcie.c
   4  *
   5  * Copyright 2011 Xillybus Ltd, http://xillybus.com
   6  *
   7  * Driver for the Xillybus FPGA/host framework using PCI Express.
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/pci.h>
  12 #include <linux/slab.h>
  13 #include "xillybus.h"
  14
  15 MODULE_DESCRIPTION("Xillybus driver for PCIe");
  16 MODULE_AUTHOR("Eli Billauer, Xillybus Ltd.");
  17 MODULE_ALIAS("xillybus_pcie");
  18 MODULE_LICENSE("GPL v2");
  19
  20 #define PCI_DEVICE_ID_XILLYBUS          0xebeb
  21
  22 #define PCI_VENDOR_ID_ACTEL             0x11aa
  23 #define PCI_VENDOR_ID_LATTICE           0x1204
  24
  25 static const char xillyname[] = "xillybus_pcie";
  26
  27 static const struct pci_device_id xillyids[] = {
  28         {PCI_DEVICE(PCI_VENDOR_ID_XILINX, PCI_DEVICE_ID_XILLYBUS)},
  29         {PCI_DEVICE(PCI_VENDOR_ID_ALTERA, PCI_DEVICE_ID_XILLYBUS)},
  30         {PCI_DEVICE(PCI_VENDOR_ID_ACTEL, PCI_DEVICE_ID_XILLYBUS)},
  31         {PCI_DEVICE(PCI_VENDOR_ID_LATTICE, PCI_DEVICE_ID_XILLYBUS)},
  32         { /* End: all zeroes */ }
  33 };
  34
  35 static int xilly_probe(struct pci_dev *pdev,
  36                        const struct pci_device_id *ent)
  37 {
  38         struct xilly_endpoint *endpoint;
  39         int rc;
  40
  41         endpoint = xillybus_init_endpoint(&pdev->dev);
  42
  43         if (!endpoint)
  44                 return -ENOMEM;
  45
  46         pci_set_drvdata(pdev, endpoint);
  47
  48         endpoint->owner = THIS_MODULE;
  49
  50         rc = pcim_enable_device(pdev);
  51         if (rc) {
  52                 dev_err(endpoint->dev,
  53                         "pcim_enable_device() failed. Aborting.\n");
  54                 return rc;
  55         }
  56
  57         /* L0s has caused packet drops. No power saving, thank you. */
  58
  59         pci_disable_link_state(pdev, PCIE_LINK_STATE_L0S);
  60
  61         if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM)) {
  62                 dev_err(endpoint->dev,
  63                         "Incorrect BAR configuration. Aborting.\n");
  64                 return -ENODEV;
  65         }
  66
  67         rc = pcim_iomap_regions(pdev, 0x01, xillyname);
  68         if (rc) {
  69                 dev_err(endpoint->dev,
  70                         "pcim_iomap_regions() failed. Aborting.\n");
  71                 return rc;
  72         }
  73
  74         endpoint->registers = pcim_iomap_table(pdev)[0];
  75
  76         pci_set_master(pdev);
  77
  78         /* Set up a single MSI interrupt */
  79         if (pci_enable_msi(pdev)) {
  80                 dev_err(endpoint->dev,
  81                         "Failed to enable MSI interrupts. Aborting.\n");
  82                 return -ENODEV;
  83         }
  84         rc = devm_request_irq(&pdev->dev, pdev->irq, xillybus_isr, 0,
  85                               xillyname, endpoint);
  86         if (rc) {
  87                 dev_err(endpoint->dev,
  88                         "Failed to register MSI handler. Aborting.\n");
  89                 return -ENODEV;
  90         }
  91
  92         /*
  93          * Some (old and buggy?) hardware drops 64-bit addressed PCIe packets,
  94          * even when the PCIe driver claims that a 64-bit mask is OK. On the
  95          * other hand, on some architectures, 64-bit addressing is mandatory.
  96          * So go for the 64-bit mask only when failing is the other option.
  97          */
  98
  99         if (!dma_set_mask(&pdev->dev, DMA_BIT_MASK(32))) {
 100                 endpoint->dma_using_dac = 0;
 101         } else if (!dma_set_mask(&pdev->dev, DMA_BIT_MASK(64))) {
 102                 endpoint->dma_using_dac = 1;
 103         } else {
 104                 dev_err(endpoint->dev, "Failed to set DMA mask. Aborting.\n");
 105                 return -ENODEV;
 106         }
 107
 108         return xillybus_endpoint_discovery(endpoint);
 109 }
 110
 111 static void xilly_remove(struct pci_dev *pdev)
 112 {
 113         struct xilly_endpoint *endpoint = pci_get_drvdata(pdev);
 114
 115         xillybus_endpoint_remove(endpoint);
 116 }
 117
 118 MODULE_DEVICE_TABLE(pci, xillyids);
 119
 120 static struct pci_driver xillybus_driver = {
 121         .name = xillyname,
 122         .id_table = xillyids,
 123         .probe = xilly_probe,
 124         .remove = xilly_remove,
 125 };
 126
 127 module_pci_driver(xillybus_driver);