qemu-patch-raspberry4/hw/pci/pci_host.c
David Gibson 568f0690fd pci: Replace pci_find_domain() with more general pci_root_bus_path()
pci_find_domain() is used in a number of places where we want an id for a
whole PCI domain (i.e. the subtree under a PCI root bus).  The trouble is
that many platforms may support multiple independent host bridges with no
hardware supplied notion of domain number.

This patch, therefore, replaces calls to pci_find_domain() with calls to
a new pci_root_bus_path() returning a string.  The new call is implemented
in terms of a new callback in the host bridge class, so it can be defined
in some way that's well defined for the platform.  When no callback is
available we fall back on the qbus name.

Most current uses of pci_find_domain() are for error or informational
messages, so the change in identifiers should be harmless.  The exception
is pci_get_dev_path(), whose results form part of migration streams.  To
maintain compatibility with old migration streams, the PIIX PCI host is
altered to always supply "0000" for this path, which matches the old domain
number (since the code didn't actually support domains other than 0).

For the pseries (spapr) PCI bridge we use a different platform-unique
identifier (pseries machines can routinely have dozens of PCI host
bridges).  Theoretically that breaks migration streams, but given that we
don't yet have migration support for pseries, it doesn't matter.

Any other machines that have working migration support including PCI
devices will need to be updated to maintain migration stream compatibility.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-07-07 23:10:57 +03:00

182 lines
5.3 KiB
C

/*
* pci_host.c
*
* Copyright (c) 2009 Isaku Yamahata <yamahata at valinux co jp>
* VA Linux Systems Japan K.K.
*
* 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.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License along
* with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include "hw/pci/pci.h"
#include "hw/pci/pci_host.h"
/* debug PCI */
//#define DEBUG_PCI
#ifdef DEBUG_PCI
#define PCI_DPRINTF(fmt, ...) \
do { printf("pci_host_data: " fmt , ## __VA_ARGS__); } while (0)
#else
#define PCI_DPRINTF(fmt, ...)
#endif
/*
* PCI address
* bit 16 - 24: bus number
* bit 8 - 15: devfun number
* bit 0 - 7: offset in configuration space of a given pci device
*/
/* the helper function to get a PCIDevice* for a given pci address */
static inline PCIDevice *pci_dev_find_by_addr(PCIBus *bus, uint32_t addr)
{
uint8_t bus_num = addr >> 16;
uint8_t devfn = addr >> 8;
return pci_find_device(bus, bus_num, devfn);
}
void pci_host_config_write_common(PCIDevice *pci_dev, uint32_t addr,
uint32_t limit, uint32_t val, uint32_t len)
{
assert(len <= 4);
pci_dev->config_write(pci_dev, addr, val, MIN(len, limit - addr));
}
uint32_t pci_host_config_read_common(PCIDevice *pci_dev, uint32_t addr,
uint32_t limit, uint32_t len)
{
assert(len <= 4);
return pci_dev->config_read(pci_dev, addr, MIN(len, limit - addr));
}
void pci_data_write(PCIBus *s, uint32_t addr, uint32_t val, int len)
{
PCIDevice *pci_dev = pci_dev_find_by_addr(s, addr);
uint32_t config_addr = addr & (PCI_CONFIG_SPACE_SIZE - 1);
if (!pci_dev) {
return;
}
PCI_DPRINTF("%s: %s: addr=%02" PRIx32 " val=%08" PRIx32 " len=%d\n",
__func__, pci_dev->name, config_addr, val, len);
pci_host_config_write_common(pci_dev, config_addr, PCI_CONFIG_SPACE_SIZE,
val, len);
}
uint32_t pci_data_read(PCIBus *s, uint32_t addr, int len)
{
PCIDevice *pci_dev = pci_dev_find_by_addr(s, addr);
uint32_t config_addr = addr & (PCI_CONFIG_SPACE_SIZE - 1);
uint32_t val;
if (!pci_dev) {
return ~0x0;
}
val = pci_host_config_read_common(pci_dev, config_addr,
PCI_CONFIG_SPACE_SIZE, len);
PCI_DPRINTF("%s: %s: addr=%02"PRIx32" val=%08"PRIx32" len=%d\n",
__func__, pci_dev->name, config_addr, val, len);
return val;
}
static void pci_host_config_write(void *opaque, hwaddr addr,
uint64_t val, unsigned len)
{
PCIHostState *s = opaque;
PCI_DPRINTF("%s addr " TARGET_FMT_plx " len %d val %"PRIx64"\n",
__func__, addr, len, val);
if (addr != 0 || len != 4) {
return;
}
s->config_reg = val;
}
static uint64_t pci_host_config_read(void *opaque, hwaddr addr,
unsigned len)
{
PCIHostState *s = opaque;
uint32_t val = s->config_reg;
PCI_DPRINTF("%s addr " TARGET_FMT_plx " len %d val %"PRIx32"\n",
__func__, addr, len, val);
return val;
}
static void pci_host_data_write(void *opaque, hwaddr addr,
uint64_t val, unsigned len)
{
PCIHostState *s = opaque;
PCI_DPRINTF("write addr " TARGET_FMT_plx " len %d val %x\n",
addr, len, (unsigned)val);
if (s->config_reg & (1u << 31))
pci_data_write(s->bus, s->config_reg | (addr & 3), val, len);
}
static uint64_t pci_host_data_read(void *opaque,
hwaddr addr, unsigned len)
{
PCIHostState *s = opaque;
uint32_t val;
if (!(s->config_reg & (1 << 31)))
return 0xffffffff;
val = pci_data_read(s->bus, s->config_reg | (addr & 3), len);
PCI_DPRINTF("read addr " TARGET_FMT_plx " len %d val %x\n",
addr, len, val);
return val;
}
const MemoryRegionOps pci_host_conf_le_ops = {
.read = pci_host_config_read,
.write = pci_host_config_write,
.endianness = DEVICE_LITTLE_ENDIAN,
};
const MemoryRegionOps pci_host_conf_be_ops = {
.read = pci_host_config_read,
.write = pci_host_config_write,
.endianness = DEVICE_BIG_ENDIAN,
};
const MemoryRegionOps pci_host_data_le_ops = {
.read = pci_host_data_read,
.write = pci_host_data_write,
.endianness = DEVICE_LITTLE_ENDIAN,
};
const MemoryRegionOps pci_host_data_be_ops = {
.read = pci_host_data_read,
.write = pci_host_data_write,
.endianness = DEVICE_BIG_ENDIAN,
};
static const TypeInfo pci_host_type_info = {
.name = TYPE_PCI_HOST_BRIDGE,
.parent = TYPE_SYS_BUS_DEVICE,
.abstract = true,
.class_size = sizeof(PCIHostBridgeClass),
.instance_size = sizeof(PCIHostState),
};
static void pci_host_register_types(void)
{
type_register_static(&pci_host_type_info);
}
type_init(pci_host_register_types)