| /* |
| * pci.c -- basic PCI support code |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License as published by the |
| * Free Software Foundation; either version 2 of the License, or (at your |
| * option) any later version. |
| * |
| * (C) Copyright 2011, Greg Ungerer <gerg@uclinux.org> |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/types.h> |
| #include <linux/mm.h> |
| #include <linux/init.h> |
| #include <linux/pci.h> |
| |
| /* |
| * From arch/i386/kernel/pci-i386.c: |
| * |
| * We need to avoid collisions with `mirrored' VGA ports |
| * and other strange ISA hardware, so we always want the |
| * addresses to be allocated in the 0x000-0x0ff region |
| * modulo 0x400. |
| * |
| * Why? Because some silly external IO cards only decode |
| * the low 10 bits of the IO address. The 0x00-0xff region |
| * is reserved for motherboard devices that decode all 16 |
| * bits, so it's ok to allocate at, say, 0x2800-0x28ff, |
| * but we want to try to avoid allocating at 0x2900-0x2bff |
| * which might be mirrored at 0x0100-0x03ff.. |
| */ |
| resource_size_t pcibios_align_resource(void *data, const struct resource *res, |
| resource_size_t size, resource_size_t align) |
| { |
| resource_size_t start = res->start; |
| |
| if ((res->flags & IORESOURCE_IO) && (start & 0x300)) |
| start = (start + 0x3ff) & ~0x3ff; |
| |
| start = (start + align - 1) & ~(align - 1); |
| |
| return start; |
| } |
| |
| /* |
| * This is taken from the ARM code for this. |
| */ |
| int pcibios_enable_device(struct pci_dev *dev, int mask) |
| { |
| struct resource *r; |
| u16 cmd, newcmd; |
| int idx; |
| |
| pci_read_config_word(dev, PCI_COMMAND, &cmd); |
| newcmd = cmd; |
| |
| for (idx = 0; idx < 6; idx++) { |
| /* Only set up the requested stuff */ |
| if (!(mask & (1 << idx))) |
| continue; |
| |
| r = dev->resource + idx; |
| if (!r->start && r->end) { |
| pr_err(KERN_ERR "PCI: Device %s not available because of resource collisions\n", |
| pci_name(dev)); |
| return -EINVAL; |
| } |
| if (r->flags & IORESOURCE_IO) |
| newcmd |= PCI_COMMAND_IO; |
| if (r->flags & IORESOURCE_MEM) |
| newcmd |= PCI_COMMAND_MEMORY; |
| } |
| |
| /* |
| * Bridges (eg, cardbus bridges) need to be fully enabled |
| */ |
| if ((dev->class >> 16) == PCI_BASE_CLASS_BRIDGE) |
| newcmd |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY; |
| |
| |
| if (newcmd != cmd) { |
| pr_info("PCI: enabling device %s (0x%04x -> 0x%04x)\n", |
| pci_name(dev), cmd, newcmd); |
| pci_write_config_word(dev, PCI_COMMAND, newcmd); |
| } |
| return 0; |
| } |
| |
| void __devinit pcibios_fixup_bus(struct pci_bus *bus) |
| { |
| struct pci_dev *dev; |
| |
| list_for_each_entry(dev, &bus->devices, bus_list) { |
| pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, 8); |
| pci_write_config_byte(dev, PCI_LATENCY_TIMER, 32); |
| } |
| } |
| |
| char __devinit *pcibios_setup(char *str) |
| { |
| return str; |
| } |
| |