mirror of
https://github.com/torvalds/linux.git
synced 2024-11-20 02:51:44 +00:00
b97ea289cf
Previously, pci_scan_root_bus() created a root PCI bus, enumerated the
devices on it, and called pci_bus_add_devices(), which made the devices
available for drivers to claim them.
Most callers assigned resources to devices after pci_scan_root_bus()
returns, which may be after drivers have claimed the devices. This is
incorrect; the PCI core should not change device resources while a driver
is managing the device.
Remove pci_bus_add_devices() from pci_scan_root_bus() and do it after any
resource assignment in the callers.
Note that ARM's pci_common_init_dev() already called pci_bus_add_devices()
after pci_scan_root_bus(), so we only need to remove the first call:
pci_common_init_dev
pcibios_init_hw
pci_scan_root_bus
pci_bus_add_devices # first call
pci_bus_assign_resources
pci_bus_add_devices # second call
[bhelgaas: changelog, drop "root_bus" var in alpha common_init_pci(),
return failure earlier in mn10300, add "return" in x86 pcibios_scan_root(),
return early if xtensa platform_pcibios_fixup() fails]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
CC: Matt Turner <mattst88@gmail.com>
CC: David Howells <dhowells@redhat.com>
CC: Tony Luck <tony.luck@intel.com>
CC: Michal Simek <monstr@monstr.eu>
CC: Ralf Baechle <ralf@linux-mips.org>
CC: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
CC: Sebastian Ott <sebott@linux.vnet.ibm.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: Chris Metcalf <cmetcalf@ezchip.com>
CC: Chris Zankel <chris@zankel.net>
CC: Max Filippov <jcmvbkbc@gmail.com>
CC: Thomas Gleixner <tglx@linutronix.de>
102 lines
2.9 KiB
C
102 lines
2.9 KiB
C
/*
|
|
* leon_pci.c: LEON Host PCI support
|
|
*
|
|
* Copyright (C) 2011 Aeroflex Gaisler AB, Daniel Hellstrom
|
|
*
|
|
* Code is partially derived from pcic.c
|
|
*/
|
|
|
|
#include <linux/of_device.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/pci.h>
|
|
#include <linux/export.h>
|
|
#include <asm/leon.h>
|
|
#include <asm/leon_pci.h>
|
|
|
|
/* The LEON architecture does not rely on a BIOS or bootloader to setup
|
|
* PCI for us. The Linux generic routines are used to setup resources,
|
|
* reset values of configuration-space register settings are preserved.
|
|
*
|
|
* PCI Memory and Prefetchable Memory is direct-mapped. However I/O Space is
|
|
* accessed through a Window which is translated to low 64KB in PCI space, the
|
|
* first 4KB is not used so 60KB is available.
|
|
*/
|
|
void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info)
|
|
{
|
|
LIST_HEAD(resources);
|
|
struct pci_bus *root_bus;
|
|
|
|
pci_add_resource_offset(&resources, &info->io_space,
|
|
info->io_space.start - 0x1000);
|
|
pci_add_resource(&resources, &info->mem_space);
|
|
info->busn.flags = IORESOURCE_BUS;
|
|
pci_add_resource(&resources, &info->busn);
|
|
|
|
root_bus = pci_scan_root_bus(&ofdev->dev, 0, info->ops, info,
|
|
&resources);
|
|
if (root_bus) {
|
|
/* Setup IRQs of all devices using custom routines */
|
|
pci_fixup_irqs(pci_common_swizzle, info->map_irq);
|
|
|
|
/* Assign devices with resources */
|
|
pci_assign_unassigned_resources();
|
|
pci_bus_add_devices(root_bus);
|
|
} else {
|
|
pci_free_resource_list(&resources);
|
|
}
|
|
}
|
|
|
|
void pcibios_fixup_bus(struct pci_bus *pbus)
|
|
{
|
|
struct pci_dev *dev;
|
|
int i, has_io, has_mem;
|
|
u16 cmd;
|
|
|
|
list_for_each_entry(dev, &pbus->devices, bus_list) {
|
|
/*
|
|
* We can not rely on that the bootloader has enabled I/O
|
|
* or memory access to PCI devices. Instead we enable it here
|
|
* if the device has BARs of respective type.
|
|
*/
|
|
has_io = has_mem = 0;
|
|
for (i = 0; i < PCI_ROM_RESOURCE; i++) {
|
|
unsigned long f = dev->resource[i].flags;
|
|
if (f & IORESOURCE_IO)
|
|
has_io = 1;
|
|
else if (f & IORESOURCE_MEM)
|
|
has_mem = 1;
|
|
}
|
|
/* ROM BARs are mapped into 32-bit memory space */
|
|
if (dev->resource[PCI_ROM_RESOURCE].end != 0) {
|
|
dev->resource[PCI_ROM_RESOURCE].flags |=
|
|
IORESOURCE_ROM_ENABLE;
|
|
has_mem = 1;
|
|
}
|
|
pci_bus_read_config_word(pbus, dev->devfn, PCI_COMMAND, &cmd);
|
|
if (has_io && !(cmd & PCI_COMMAND_IO)) {
|
|
#ifdef CONFIG_PCI_DEBUG
|
|
printk(KERN_INFO "LEONPCI: Enabling I/O for dev %s\n",
|
|
pci_name(dev));
|
|
#endif
|
|
cmd |= PCI_COMMAND_IO;
|
|
pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
|
|
cmd);
|
|
}
|
|
if (has_mem && !(cmd & PCI_COMMAND_MEMORY)) {
|
|
#ifdef CONFIG_PCI_DEBUG
|
|
printk(KERN_INFO "LEONPCI: Enabling MEMORY for dev"
|
|
"%s\n", pci_name(dev));
|
|
#endif
|
|
cmd |= PCI_COMMAND_MEMORY;
|
|
pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
|
|
cmd);
|
|
}
|
|
}
|
|
}
|
|
|
|
resource_size_t pcibios_align_resource(void *data, const struct resource *res,
|
|
resource_size_t size, resource_size_t align)
|
|
{
|
|
return res->start;
|
|
}
|