PCI: pcie: Ensure hotplug ports have a minimum number of resources

In general a BIOS may goof or we may hotplug in a hotplug controller.
In either case the kernel needs to reserve resources for plugging
in more devices in the future instead of creating a minimal resource
assignment.

We already do this for cardbus bridges I am just adding a variant
for pcie bridges.

v2: Make testing for pcie hotplug bridges based on a flag.

    So far we only set the flag for pcie but a header_quirk
    could easily be added for the non-standard pci hotplug
    bridges.

Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Eric W. Biederman 2009-09-09 14:09:24 -07:00 committed by Jesse Barnes
parent 0ba379ec0f
commit 28760489a3
4 changed files with 49 additions and 5 deletions

View File

@ -41,6 +41,12 @@ int pci_domains_supported = 1;
unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
#define DEFAULT_HOTPLUG_IO_SIZE (256)
#define DEFAULT_HOTPLUG_MEM_SIZE (2*1024*1024)
/* pci=hpmemsize=nnM,hpiosize=nn can override this */
unsigned long pci_hotplug_io_size = DEFAULT_HOTPLUG_IO_SIZE;
unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
/**
* pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
* @bus: pointer to PCI bus structure to search
@ -2732,6 +2738,10 @@ static int __init pci_setup(char *str)
strlen(str + 19));
} else if (!strncmp(str, "ecrc=", 5)) {
pcie_ecrc_get_policy(str + 5);
} else if (!strncmp(str, "hpiosize=", 9)) {
pci_hotplug_io_size = memparse(str + 9, &str);
} else if (!strncmp(str, "hpmemsize=", 10)) {
pci_hotplug_mem_size = memparse(str + 10, &str);
} else {
printk(KERN_ERR "PCI: Unknown option `%s'\n",
str);

View File

@ -697,6 +697,23 @@ static void set_pcie_port_type(struct pci_dev *pdev)
pdev->pcie_type = (reg16 & PCI_EXP_FLAGS_TYPE) >> 4;
}
static void set_pcie_hotplug_bridge(struct pci_dev *pdev)
{
int pos;
u16 reg16;
u32 reg32;
pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
if (!pos)
return;
pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &reg16);
if (!(reg16 & PCI_EXP_FLAGS_SLOT))
return;
pci_read_config_dword(pdev, pos + PCI_EXP_SLTCAP, &reg32);
if (reg32 & PCI_EXP_SLTCAP_HPC)
pdev->is_hotplug_bridge = 1;
}
#define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
/**
@ -804,6 +821,7 @@ int pci_setup_device(struct pci_dev *dev)
pci_read_irq(dev);
dev->transparent = ((dev->class & 0xff) == 1);
pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
set_pcie_hotplug_bridge(dev);
break;
case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */

View File

@ -309,7 +309,7 @@ static struct resource *find_free_bus_resource(struct pci_bus *bus, unsigned lon
since these windows have 4K granularity and the IO ranges
of non-bridge PCI devices are limited to 256 bytes.
We must be careful with the ISA aliasing though. */
static void pbus_size_io(struct pci_bus *bus)
static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size)
{
struct pci_dev *dev;
struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
@ -336,6 +336,8 @@ static void pbus_size_io(struct pci_bus *bus)
size1 += r_size;
}
}
if (size < min_size)
size = min_size;
/* To be fixed in 2.5: we should have sort of HAVE_ISA
flag in the struct pci_bus. */
#if defined(CONFIG_ISA) || defined(CONFIG_EISA)
@ -354,7 +356,8 @@ static void pbus_size_io(struct pci_bus *bus)
/* Calculate the size of the bus and minimal alignment which
guarantees that all child resources fit in this size. */
static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, unsigned long type)
static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
unsigned long type, resource_size_t min_size)
{
struct pci_dev *dev;
resource_size_t min_align, align, size;
@ -404,6 +407,8 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, unsigned long
mem64_mask &= r->flags & IORESOURCE_MEM_64;
}
}
if (size < min_size)
size = min_size;
align = 0;
min_align = 0;
@ -483,6 +488,7 @@ void __ref pci_bus_size_bridges(struct pci_bus *bus)
{
struct pci_dev *dev;
unsigned long mask, prefmask;
resource_size_t min_mem_size = 0, min_io_size = 0;
list_for_each_entry(dev, &bus->devices, bus_list) {
struct pci_bus *b = dev->subordinate;
@ -512,8 +518,12 @@ void __ref pci_bus_size_bridges(struct pci_bus *bus)
case PCI_CLASS_BRIDGE_PCI:
pci_bridge_check_ranges(bus);
if (bus->self->is_hotplug_bridge) {
min_io_size = pci_hotplug_io_size;
min_mem_size = pci_hotplug_mem_size;
}
default:
pbus_size_io(bus);
pbus_size_io(bus, min_io_size);
/* If the bridge supports prefetchable range, size it
separately. If it doesn't, or its prefetchable window
has already been allocated by arch code, try
@ -521,9 +531,11 @@ void __ref pci_bus_size_bridges(struct pci_bus *bus)
resources. */
mask = IORESOURCE_MEM;
prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
if (pbus_size_mem(bus, prefmask, prefmask))
if (pbus_size_mem(bus, prefmask, prefmask, min_mem_size))
mask = prefmask; /* Success, size non-prefetch only. */
pbus_size_mem(bus, mask, IORESOURCE_MEM);
else
min_mem_size += min_mem_size;
pbus_size_mem(bus, mask, IORESOURCE_MEM, min_mem_size);
break;
}
}

View File

@ -278,6 +278,7 @@ struct pci_dev {
unsigned int is_physfn:1;
unsigned int is_virtfn:1;
unsigned int reset_fn:1;
unsigned int is_hotplug_bridge:1;
pci_dev_flags_t dev_flags;
atomic_t enable_cnt; /* pci_enable_device has been called */
@ -1245,6 +1246,9 @@ extern int pci_pci_problems;
extern unsigned long pci_cardbus_io_size;
extern unsigned long pci_cardbus_mem_size;
extern unsigned long pci_hotplug_io_size;
extern unsigned long pci_hotplug_mem_size;
int pcibios_add_platform_entries(struct pci_dev *dev);
void pcibios_disable_device(struct pci_dev *dev);
int pcibios_set_pcie_reset_state(struct pci_dev *dev,