linux_dsm_epyc7002/arch/powerpc/kernel/pci_64.c
Benjamin Herrenschmidt ad892a63f6 powerpc: Fix PCI ROM access
A couple of issues crept in since about 2.6.27 related to accessing PCI
device ROMs on various powerpc machines.

First, historically, we don't allocate the ROM resource in the resource
tree. I'm not entirely certain of why, I susepct they often contained
garbage on x86 but it's hard to tell. This causes the current generic
code to always call pci_assign_resource() when trying to access the said
ROM from sysfs, which will try to re-assign some new address regardless
of what the ROM BAR was already set to at boot time. This can be a
problem on hypervisor platforms like pSeries where we aren't supposed
to move PCI devices around (and in fact probably can't).

Second, our code that generates the PCI tree from the OF device-tree
(instead of doing config space probing) which we mostly use on pseries
at the moment, didn't set the (new) flag IORESOURCE_SIZEALIGN on any
resource. That means that any attempt at re-assigning such a resource
with pci_assign_resource() would fail due to resource_alignment()
returning 0.

This fixes this by doing these two things:

 - The code that calculates resource flags based on the OF device-node
is improved to set IORESOURCE_SIZEALIGN on any valid BAR, and while at
it also set IORESOURCE_READONLY for ROMs since we were lacking that too

 - We now allocate ROM resources as part of the resource tree. However
to limit the chances of nasty conflicts due to busted firmwares, we
only do it on the second pass of our two-passes allocation scheme,
so that all valid and enabled BARs get precedence.

This brings pSeries back the ability to access PCI ROMs via sysfs (and
thus initialize various video cards from X etc...).

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-05-15 16:43:42 +10:00

602 lines
16 KiB
C

/*
* Port for PPC64 David Engebretsen, IBM Corp.
* Contains common pci routines for ppc64 platform, pSeries and iSeries brands.
*
* Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
* Rework, based on alpha PCI 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.
*/
#undef DEBUG
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/mm.h>
#include <linux/list.h>
#include <linux/syscalls.h>
#include <linux/irq.h>
#include <linux/vmalloc.h>
#include <asm/processor.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pci-bridge.h>
#include <asm/byteorder.h>
#include <asm/machdep.h>
#include <asm/ppc-pci.h>
unsigned long pci_probe_only = 1;
/* pci_io_base -- the base address from which io bars are offsets.
* This is the lowest I/O base address (so bar values are always positive),
* and it *must* be the start of ISA space if an ISA bus exists because
* ISA drivers use hard coded offsets. If no ISA bus exists nothing
* is mapped on the first 64K of IO space
*/
unsigned long pci_io_base = ISA_IO_BASE;
EXPORT_SYMBOL(pci_io_base);
static void fixup_broken_pcnet32(struct pci_dev* dev)
{
if ((dev->class>>8 == PCI_CLASS_NETWORK_ETHERNET)) {
dev->vendor = PCI_VENDOR_ID_AMD;
pci_write_config_word(dev, PCI_VENDOR_ID, PCI_VENDOR_ID_AMD);
}
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_TRIDENT, PCI_ANY_ID, fixup_broken_pcnet32);
static u32 get_int_prop(struct device_node *np, const char *name, u32 def)
{
const u32 *prop;
int len;
prop = of_get_property(np, name, &len);
if (prop && len >= 4)
return *prop;
return def;
}
static unsigned int pci_parse_of_flags(u32 addr0, int bridge)
{
unsigned int flags = 0;
if (addr0 & 0x02000000) {
flags = IORESOURCE_MEM | PCI_BASE_ADDRESS_SPACE_MEMORY;
flags |= (addr0 >> 22) & PCI_BASE_ADDRESS_MEM_TYPE_64;
flags |= (addr0 >> 28) & PCI_BASE_ADDRESS_MEM_TYPE_1M;
if (addr0 & 0x40000000)
flags |= IORESOURCE_PREFETCH
| PCI_BASE_ADDRESS_MEM_PREFETCH;
/* Note: We don't know whether the ROM has been left enabled
* by the firmware or not. We mark it as disabled (ie, we do
* not set the IORESOURCE_ROM_ENABLE flag) for now rather than
* do a config space read, it will be force-enabled if needed
*/
if (!bridge && (addr0 & 0xff) == 0x30)
flags |= IORESOURCE_READONLY;
} else if (addr0 & 0x01000000)
flags = IORESOURCE_IO | PCI_BASE_ADDRESS_SPACE_IO;
if (flags)
flags |= IORESOURCE_SIZEALIGN;
return flags;
}
static void pci_parse_of_addrs(struct device_node *node, struct pci_dev *dev)
{
u64 base, size;
unsigned int flags;
struct resource *res;
const u32 *addrs;
u32 i;
int proplen;
addrs = of_get_property(node, "assigned-addresses", &proplen);
if (!addrs)
return;
pr_debug(" parse addresses (%d bytes) @ %p\n", proplen, addrs);
for (; proplen >= 20; proplen -= 20, addrs += 5) {
flags = pci_parse_of_flags(addrs[0], 0);
if (!flags)
continue;
base = of_read_number(&addrs[1], 2);
size = of_read_number(&addrs[3], 2);
if (!size)
continue;
i = addrs[0] & 0xff;
pr_debug(" base: %llx, size: %llx, i: %x\n",
(unsigned long long)base,
(unsigned long long)size, i);
if (PCI_BASE_ADDRESS_0 <= i && i <= PCI_BASE_ADDRESS_5) {
res = &dev->resource[(i - PCI_BASE_ADDRESS_0) >> 2];
} else if (i == dev->rom_base_reg) {
res = &dev->resource[PCI_ROM_RESOURCE];
flags |= IORESOURCE_READONLY | IORESOURCE_CACHEABLE;
} else {
printk(KERN_ERR "PCI: bad cfg reg num 0x%x\n", i);
continue;
}
res->start = base;
res->end = base + size - 1;
res->flags = flags;
res->name = pci_name(dev);
}
}
struct pci_dev *of_create_pci_dev(struct device_node *node,
struct pci_bus *bus, int devfn)
{
struct pci_dev *dev;
const char *type;
dev = alloc_pci_dev();
if (!dev)
return NULL;
type = of_get_property(node, "device_type", NULL);
if (type == NULL)
type = "";
pr_debug(" create device, devfn: %x, type: %s\n", devfn, type);
dev->bus = bus;
dev->sysdata = node;
dev->dev.parent = bus->bridge;
dev->dev.bus = &pci_bus_type;
dev->devfn = devfn;
dev->multifunction = 0; /* maybe a lie? */
dev->vendor = get_int_prop(node, "vendor-id", 0xffff);
dev->device = get_int_prop(node, "device-id", 0xffff);
dev->subsystem_vendor = get_int_prop(node, "subsystem-vendor-id", 0);
dev->subsystem_device = get_int_prop(node, "subsystem-id", 0);
dev->cfg_size = pci_cfg_space_size(dev);
dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(bus),
dev->bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn));
dev->class = get_int_prop(node, "class-code", 0);
dev->revision = get_int_prop(node, "revision-id", 0);
pr_debug(" class: 0x%x\n", dev->class);
pr_debug(" revision: 0x%x\n", dev->revision);
dev->current_state = 4; /* unknown power state */
dev->error_state = pci_channel_io_normal;
dev->dma_mask = 0xffffffff;
if (!strcmp(type, "pci") || !strcmp(type, "pciex")) {
/* a PCI-PCI bridge */
dev->hdr_type = PCI_HEADER_TYPE_BRIDGE;
dev->rom_base_reg = PCI_ROM_ADDRESS1;
} else if (!strcmp(type, "cardbus")) {
dev->hdr_type = PCI_HEADER_TYPE_CARDBUS;
} else {
dev->hdr_type = PCI_HEADER_TYPE_NORMAL;
dev->rom_base_reg = PCI_ROM_ADDRESS;
/* Maybe do a default OF mapping here */
dev->irq = NO_IRQ;
}
pci_parse_of_addrs(node, dev);
pr_debug(" adding to system ...\n");
pci_device_add(dev, bus);
return dev;
}
EXPORT_SYMBOL(of_create_pci_dev);
static void __devinit __of_scan_bus(struct device_node *node,
struct pci_bus *bus, int rescan_existing)
{
struct device_node *child;
const u32 *reg;
int reglen, devfn;
struct pci_dev *dev;
pr_debug("of_scan_bus(%s) bus no %d... \n",
node->full_name, bus->number);
/* Scan direct children */
for_each_child_of_node(node, child) {
pr_debug(" * %s\n", child->full_name);
reg = of_get_property(child, "reg", &reglen);
if (reg == NULL || reglen < 20)
continue;
devfn = (reg[0] >> 8) & 0xff;
/* create a new pci_dev for this device */
dev = of_create_pci_dev(child, bus, devfn);
if (!dev)
continue;
pr_debug(" dev header type: %x\n", dev->hdr_type);
}
/* Apply all fixups necessary. We don't fixup the bus "self"
* for an existing bridge that is being rescanned
*/
if (!rescan_existing)
pcibios_setup_bus_self(bus);
pcibios_setup_bus_devices(bus);
/* Now scan child busses */
list_for_each_entry(dev, &bus->devices, bus_list) {
if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
struct device_node *child = pci_device_to_OF_node(dev);
if (dev)
of_scan_pci_bridge(child, dev);
}
}
}
void __devinit of_scan_bus(struct device_node *node,
struct pci_bus *bus)
{
__of_scan_bus(node, bus, 0);
}
EXPORT_SYMBOL_GPL(of_scan_bus);
void __devinit of_rescan_bus(struct device_node *node,
struct pci_bus *bus)
{
__of_scan_bus(node, bus, 1);
}
EXPORT_SYMBOL_GPL(of_rescan_bus);
void __devinit of_scan_pci_bridge(struct device_node *node,
struct pci_dev *dev)
{
struct pci_bus *bus;
const u32 *busrange, *ranges;
int len, i, mode;
struct resource *res;
unsigned int flags;
u64 size;
pr_debug("of_scan_pci_bridge(%s)\n", node->full_name);
/* parse bus-range property */
busrange = of_get_property(node, "bus-range", &len);
if (busrange == NULL || len != 8) {
printk(KERN_DEBUG "Can't get bus-range for PCI-PCI bridge %s\n",
node->full_name);
return;
}
ranges = of_get_property(node, "ranges", &len);
if (ranges == NULL) {
printk(KERN_DEBUG "Can't get ranges for PCI-PCI bridge %s\n",
node->full_name);
return;
}
bus = pci_add_new_bus(dev->bus, dev, busrange[0]);
if (!bus) {
printk(KERN_ERR "Failed to create pci bus for %s\n",
node->full_name);
return;
}
bus->primary = dev->bus->number;
bus->subordinate = busrange[1];
bus->bridge_ctl = 0;
bus->sysdata = node;
/* parse ranges property */
/* PCI #address-cells == 3 and #size-cells == 2 always */
res = &dev->resource[PCI_BRIDGE_RESOURCES];
for (i = 0; i < PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES; ++i) {
res->flags = 0;
bus->resource[i] = res;
++res;
}
i = 1;
for (; len >= 32; len -= 32, ranges += 8) {
flags = pci_parse_of_flags(ranges[0], 1);
size = of_read_number(&ranges[6], 2);
if (flags == 0 || size == 0)
continue;
if (flags & IORESOURCE_IO) {
res = bus->resource[0];
if (res->flags) {
printk(KERN_ERR "PCI: ignoring extra I/O range"
" for bridge %s\n", node->full_name);
continue;
}
} else {
if (i >= PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES) {
printk(KERN_ERR "PCI: too many memory ranges"
" for bridge %s\n", node->full_name);
continue;
}
res = bus->resource[i];
++i;
}
res->start = of_read_number(&ranges[1], 2);
res->end = res->start + size - 1;
res->flags = flags;
}
sprintf(bus->name, "PCI Bus %04x:%02x", pci_domain_nr(bus),
bus->number);
pr_debug(" bus name: %s\n", bus->name);
mode = PCI_PROBE_NORMAL;
if (ppc_md.pci_probe_mode)
mode = ppc_md.pci_probe_mode(bus);
pr_debug(" probe mode: %d\n", mode);
if (mode == PCI_PROBE_DEVTREE)
of_scan_bus(node, bus);
else if (mode == PCI_PROBE_NORMAL)
pci_scan_child_bus(bus);
}
EXPORT_SYMBOL(of_scan_pci_bridge);
void __devinit scan_phb(struct pci_controller *hose)
{
struct pci_bus *bus;
struct device_node *node = hose->dn;
int mode;
pr_debug("PCI: Scanning PHB %s\n",
node ? node->full_name : "<NO NAME>");
/* Create an empty bus for the toplevel */
bus = pci_create_bus(hose->parent, hose->first_busno, hose->ops, node);
if (bus == NULL) {
printk(KERN_ERR "Failed to create bus for PCI domain %04x\n",
hose->global_number);
return;
}
bus->secondary = hose->first_busno;
hose->bus = bus;
/* Get some IO space for the new PHB */
pcibios_map_io_space(bus);
/* Wire up PHB bus resources */
pcibios_setup_phb_resources(hose);
/* Get probe mode and perform scan */
mode = PCI_PROBE_NORMAL;
if (node && ppc_md.pci_probe_mode)
mode = ppc_md.pci_probe_mode(bus);
pr_debug(" probe mode: %d\n", mode);
if (mode == PCI_PROBE_DEVTREE) {
bus->subordinate = hose->last_busno;
of_scan_bus(node, bus);
}
if (mode == PCI_PROBE_NORMAL)
hose->last_busno = bus->subordinate = pci_scan_child_bus(bus);
}
static int __init pcibios_init(void)
{
struct pci_controller *hose, *tmp;
printk(KERN_INFO "PCI: Probing PCI hardware\n");
/* For now, override phys_mem_access_prot. If we need it,g
* later, we may move that initialization to each ppc_md
*/
ppc_md.phys_mem_access_prot = pci_phys_mem_access_prot;
if (pci_probe_only)
ppc_pci_flags |= PPC_PCI_PROBE_ONLY;
/* On ppc64, we always enable PCI domains and we keep domain 0
* backward compatible in /proc for video cards
*/
ppc_pci_flags |= PPC_PCI_ENABLE_PROC_DOMAINS | PPC_PCI_COMPAT_DOMAIN_0;
/* Scan all of the recorded PCI controllers. */
list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
scan_phb(hose);
pci_bus_add_devices(hose->bus);
}
/* Call common code to handle resource allocation */
pcibios_resource_survey();
printk(KERN_DEBUG "PCI: Probing PCI hardware done\n");
return 0;
}
subsys_initcall(pcibios_init);
#ifdef CONFIG_HOTPLUG
int pcibios_unmap_io_space(struct pci_bus *bus)
{
struct pci_controller *hose;
WARN_ON(bus == NULL);
/* If this is not a PHB, we only flush the hash table over
* the area mapped by this bridge. We don't play with the PTE
* mappings since we might have to deal with sub-page alignemnts
* so flushing the hash table is the only sane way to make sure
* that no hash entries are covering that removed bridge area
* while still allowing other busses overlapping those pages
*/
if (bus->self) {
struct resource *res = bus->resource[0];
pr_debug("IO unmapping for PCI-PCI bridge %s\n",
pci_name(bus->self));
__flush_hash_table_range(&init_mm, res->start + _IO_BASE,
res->end + _IO_BASE + 1);
return 0;
}
/* Get the host bridge */
hose = pci_bus_to_host(bus);
/* Check if we have IOs allocated */
if (hose->io_base_alloc == 0)
return 0;
pr_debug("IO unmapping for PHB %s\n", hose->dn->full_name);
pr_debug(" alloc=0x%p\n", hose->io_base_alloc);
/* This is a PHB, we fully unmap the IO area */
vunmap(hose->io_base_alloc);
return 0;
}
EXPORT_SYMBOL_GPL(pcibios_unmap_io_space);
#endif /* CONFIG_HOTPLUG */
int __devinit pcibios_map_io_space(struct pci_bus *bus)
{
struct vm_struct *area;
unsigned long phys_page;
unsigned long size_page;
unsigned long io_virt_offset;
struct pci_controller *hose;
WARN_ON(bus == NULL);
/* If this not a PHB, nothing to do, page tables still exist and
* thus HPTEs will be faulted in when needed
*/
if (bus->self) {
pr_debug("IO mapping for PCI-PCI bridge %s\n",
pci_name(bus->self));
pr_debug(" virt=0x%016llx...0x%016llx\n",
bus->resource[0]->start + _IO_BASE,
bus->resource[0]->end + _IO_BASE);
return 0;
}
/* Get the host bridge */
hose = pci_bus_to_host(bus);
phys_page = _ALIGN_DOWN(hose->io_base_phys, PAGE_SIZE);
size_page = _ALIGN_UP(hose->pci_io_size, PAGE_SIZE);
/* Make sure IO area address is clear */
hose->io_base_alloc = NULL;
/* If there's no IO to map on that bus, get away too */
if (hose->pci_io_size == 0 || hose->io_base_phys == 0)
return 0;
/* Let's allocate some IO space for that guy. We don't pass
* VM_IOREMAP because we don't care about alignment tricks that
* the core does in that case. Maybe we should due to stupid card
* with incomplete address decoding but I'd rather not deal with
* those outside of the reserved 64K legacy region.
*/
area = __get_vm_area(size_page, 0, PHB_IO_BASE, PHB_IO_END);
if (area == NULL)
return -ENOMEM;
hose->io_base_alloc = area->addr;
hose->io_base_virt = (void __iomem *)(area->addr +
hose->io_base_phys - phys_page);
pr_debug("IO mapping for PHB %s\n", hose->dn->full_name);
pr_debug(" phys=0x%016llx, virt=0x%p (alloc=0x%p)\n",
hose->io_base_phys, hose->io_base_virt, hose->io_base_alloc);
pr_debug(" size=0x%016lx (alloc=0x%016lx)\n",
hose->pci_io_size, size_page);
/* Establish the mapping */
if (__ioremap_at(phys_page, area->addr, size_page,
_PAGE_NO_CACHE | _PAGE_GUARDED) == NULL)
return -ENOMEM;
/* Fixup hose IO resource */
io_virt_offset = (unsigned long)hose->io_base_virt - _IO_BASE;
hose->io_resource.start += io_virt_offset;
hose->io_resource.end += io_virt_offset;
pr_debug(" hose->io_resource=0x%016llx...0x%016llx\n",
hose->io_resource.start, hose->io_resource.end);
return 0;
}
EXPORT_SYMBOL_GPL(pcibios_map_io_space);
#define IOBASE_BRIDGE_NUMBER 0
#define IOBASE_MEMORY 1
#define IOBASE_IO 2
#define IOBASE_ISA_IO 3
#define IOBASE_ISA_MEM 4
long sys_pciconfig_iobase(long which, unsigned long in_bus,
unsigned long in_devfn)
{
struct pci_controller* hose;
struct list_head *ln;
struct pci_bus *bus = NULL;
struct device_node *hose_node;
/* Argh ! Please forgive me for that hack, but that's the
* simplest way to get existing XFree to not lockup on some
* G5 machines... So when something asks for bus 0 io base
* (bus 0 is HT root), we return the AGP one instead.
*/
if (in_bus == 0 && machine_is_compatible("MacRISC4")) {
struct device_node *agp;
agp = of_find_compatible_node(NULL, NULL, "u3-agp");
if (agp)
in_bus = 0xf0;
of_node_put(agp);
}
/* That syscall isn't quite compatible with PCI domains, but it's
* used on pre-domains setup. We return the first match
*/
for (ln = pci_root_buses.next; ln != &pci_root_buses; ln = ln->next) {
bus = pci_bus_b(ln);
if (in_bus >= bus->number && in_bus <= bus->subordinate)
break;
bus = NULL;
}
if (bus == NULL || bus->sysdata == NULL)
return -ENODEV;
hose_node = (struct device_node *)bus->sysdata;
hose = PCI_DN(hose_node)->phb;
switch (which) {
case IOBASE_BRIDGE_NUMBER:
return (long)hose->first_busno;
case IOBASE_MEMORY:
return (long)hose->pci_mem_offset;
case IOBASE_IO:
return (long)hose->io_base_phys;
case IOBASE_ISA_IO:
return (long)isa_io_base;
case IOBASE_ISA_MEM:
return -EINVAL;
}
return -EOPNOTSUPP;
}
#ifdef CONFIG_NUMA
int pcibus_to_node(struct pci_bus *bus)
{
struct pci_controller *phb = pci_bus_to_host(bus);
return phb->node;
}
EXPORT_SYMBOL(pcibus_to_node);
#endif