LXR linux/arch/sparc/kernel/leon

   1/*
   2 * leon_pci.c: LEON Host PCI support
   3 *
   4 * Copyright (C) 2011 Aeroflex Gaisler AB, Daniel Hellstrom
   5 *
   6 * Code is partially derived from pcic.c
   7 */
   8
   9#include <linux/of_device.h>
  10#include <linux/kernel.h>
  11#include <linux/pci.h>
  12#include <linux/export.h>
  13#include <asm/leon.h>
  14#include <asm/leon_pci.h>
  15
  16/* The LEON architecture does not rely on a BIOS or bootloader to setup
  17 * PCI for us. The Linux generic routines are used to setup resources,
  18 * reset values of configuration-space register settings are preserved.
  19 *
  20 * PCI Memory and Prefetchable Memory is direct-mapped. However I/O Space is
  21 * accessed through a Window which is translated to low 64KB in PCI space, the
  22 * first 4KB is not used so 60KB is available.
  23 */
  24void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info)
  25{
  26        LIST_HEAD(resources);
  27        struct pci_bus *root_bus;
  28
  29        pci_add_resource_offset(&resources, &info->io_space,
  30                                info->io_space.start - 0x1000);
  31        pci_add_resource(&resources, &info->mem_space);
  32        info->busn.flags = IORESOURCE_BUS;
  33        pci_add_resource(&resources, &info->busn);
  34
  35        root_bus = pci_scan_root_bus(&ofdev->dev, 0, info->ops, info,
  36                                     &resources);
  37        if (!root_bus) {
  38                pci_free_resource_list(&resources);
  39                return;
  40        }
  41
  42        /* Setup IRQs of all devices using custom routines */
  43        pci_fixup_irqs(pci_common_swizzle, info->map_irq);
  44
  45        /* Assign devices with resources */
  46        pci_assign_unassigned_resources();
  47        pci_bus_add_devices(root_bus);
  48}
  49
  50void pcibios_fixup_bus(struct pci_bus *pbus)
  51{
  52        struct pci_dev *dev;
  53        int i, has_io, has_mem;
  54        u16 cmd;
  55
  56        list_for_each_entry(dev, &pbus->devices, bus_list) {
  57                /*
  58                 * We can not rely on that the bootloader has enabled I/O
  59                 * or memory access to PCI devices. Instead we enable it here
  60                 * if the device has BARs of respective type.
  61                 */
  62                has_io = has_mem = 0;
  63                for (i = 0; i < PCI_ROM_RESOURCE; i++) {
  64                        unsigned long f = dev->resource[i].flags;
  65                        if (f & IORESOURCE_IO)
  66                                has_io = 1;
  67                        else if (f & IORESOURCE_MEM)
  68                                has_mem = 1;
  69                }
  70                /* ROM BARs are mapped into 32-bit memory space */
  71                if (dev->resource[PCI_ROM_RESOURCE].end != 0) {
  72                        dev->resource[PCI_ROM_RESOURCE].flags |=
  73                                                        IORESOURCE_ROM_ENABLE;
  74                        has_mem = 1;
  75                }
  76                pci_bus_read_config_word(pbus, dev->devfn, PCI_COMMAND, &cmd);
  77                if (has_io && !(cmd & PCI_COMMAND_IO)) {
  78#ifdef CONFIG_PCI_DEBUG
  79                        printk(KERN_INFO "LEONPCI: Enabling I/O for dev %s\n",
  80                                         pci_name(dev));
  81#endif
  82                        cmd |= PCI_COMMAND_IO;
  83                        pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
  84                                                                        cmd);
  85                }
  86                if (has_mem && !(cmd & PCI_COMMAND_MEMORY)) {
  87#ifdef CONFIG_PCI_DEBUG
  88                        printk(KERN_INFO "LEONPCI: Enabling MEMORY for dev"
  89                                         "%s\n", pci_name(dev));
  90#endif
  91                        cmd |= PCI_COMMAND_MEMORY;
  92                        pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
  93                                                                        cmd);
  94                }
  95        }
  96}
  97
  98resource_size_t pcibios_align_resource(void *data, const struct resource *res,
  99                                resource_size_t size, resource_size_t align)
 100{
 101        return res->start;
 102}
 103