#include <linux/pci.h>
#include <linux/init.h>
#include <linux/acpi.h>
+#include <asm/e820.h>
#include "pci.h"
+/* aperture is up to 256MB but BIOS may reserve less */
+#define MMCONFIG_APER_MIN (2 * 1024*1024)
+#define MMCONFIG_APER_MAX (256 * 1024*1024)
+
+/* Assume systems with more busses have correct MCFG */
+#define MAX_CHECK_BUS 16
+
#define mmcfg_virt_addr ((void __iomem *) fix_to_virt(FIX_PCIE_MCFG))
/* The base address of the last MMCONFIG device accessed */
static u32 mmcfg_last_accessed_device;
+static int mmcfg_last_accessed_cpu;
-static DECLARE_BITMAP(fallback_slots, 32);
+static DECLARE_BITMAP(fallback_slots, MAX_CHECK_BUS*32);
/*
* Functions for accessing PCI configuration space with MMCONFIG accesses
int cfg_num = -1;
struct acpi_table_mcfg_config *cfg;
- if (seg == 0 && bus == 0 &&
- test_bit(PCI_SLOT(devfn), fallback_slots))
+ if (seg == 0 && bus < MAX_CHECK_BUS &&
+ test_bit(PCI_SLOT(devfn) + 32*bus, fallback_slots))
return 0;
while (1) {
return 0;
}
-static inline void pci_exp_set_dev_base(unsigned int base, int bus, int devfn)
+/*
+ * This is always called under pci_config_lock
+ */
+static void pci_exp_set_dev_base(unsigned int base, int bus, int devfn)
{
u32 dev_base = base | (bus << 20) | (devfn << 12);
- if (dev_base != mmcfg_last_accessed_device) {
+ int cpu = smp_processor_id();
+ if (dev_base != mmcfg_last_accessed_device ||
+ cpu != mmcfg_last_accessed_cpu) {
mmcfg_last_accessed_device = dev_base;
+ mmcfg_last_accessed_cpu = cpu;
set_fixmap_nocache(FIX_PCIE_MCFG, dev_base);
}
}
unsigned long flags;
u32 base;
- if (!value || (bus > 255) || (devfn > 255) || (reg > 4095))
+ if ((bus > 255) || (devfn > 255) || (reg > 4095)) {
+ *value = -1;
return -EINVAL;
+ }
base = get_base_addr(seg, bus, devfn);
if (!base)
Normally this can be expressed in the MCFG by not listing them
and assigning suitable _SEGs, but this isn't implemented in some BIOS.
Instead try to discover all devices on bus 0 that are unreachable using MM
- and fallback for them.
- We only do this for bus 0/seg 0 */
+ and fallback for them. */
static __init void unreachable_devices(void)
{
- int i;
+ int i, k;
unsigned long flags;
- for (i = 0; i < 32; i++) {
- u32 val1;
- u32 addr;
-
- pci_conf1_read(0, 0, PCI_DEVFN(i, 0), 0, 4, &val1);
- if (val1 == 0xffffffff)
- continue;
-
- /* Locking probably not needed, but safer */
- spin_lock_irqsave(&pci_config_lock, flags);
- addr = get_base_addr(0, 0, PCI_DEVFN(i, 0));
- if (addr != 0)
- pci_exp_set_dev_base(addr, 0, PCI_DEVFN(i, 0));
- if (addr == 0 || readl((u32 __iomem *)mmcfg_virt_addr) != val1)
- set_bit(i, fallback_slots);
- spin_unlock_irqrestore(&pci_config_lock, flags);
+ for (k = 0; k < MAX_CHECK_BUS; k++) {
+ for (i = 0; i < 32; i++) {
+ u32 val1;
+ u32 addr;
+
+ pci_conf1_read(0, k, PCI_DEVFN(i, 0), 0, 4, &val1);
+ if (val1 == 0xffffffff)
+ continue;
+
+ /* Locking probably not needed, but safer */
+ spin_lock_irqsave(&pci_config_lock, flags);
+ addr = get_base_addr(0, k, PCI_DEVFN(i, 0));
+ if (addr != 0)
+ pci_exp_set_dev_base(addr, k, PCI_DEVFN(i, 0));
+ if (addr == 0 ||
+ readl((u32 __iomem *)mmcfg_virt_addr) != val1) {
+ set_bit(i + 32*k, fallback_slots);
+ printk(KERN_NOTICE
+ "PCI: No mmconfig possible on %x:%x\n", k, i);
+ }
+ spin_unlock_irqrestore(&pci_config_lock, flags);
+ }
}
}
-static int __init pci_mmcfg_init(void)
+void __init pci_mmcfg_init(int type)
{
if ((pci_probe & PCI_PROBE_MMCONF) == 0)
- goto out;
+ return;
acpi_table_parse(ACPI_MCFG, acpi_parse_mcfg);
if ((pci_mmcfg_config_num == 0) ||
(pci_mmcfg_config == NULL) ||
(pci_mmcfg_config[0].base_address == 0))
- goto out;
+ return;
+
+ /* Only do this check when type 1 works. If it doesn't work
+ assume we run on a Mac and always use MCFG */
+ if (type == 1 && !e820_all_mapped(pci_mmcfg_config[0].base_address,
+ pci_mmcfg_config[0].base_address + MMCONFIG_APER_MIN,
+ E820_RESERVED)) {
+ printk(KERN_ERR "PCI: BIOS Bug: MCFG area at %x is not E820-reserved\n",
+ pci_mmcfg_config[0].base_address);
+ printk(KERN_ERR "PCI: Not using MMCONFIG.\n");
+ return;
+ }
printk(KERN_INFO "PCI: Using MMCONFIG\n");
raw_pci_ops = &pci_mmcfg;
pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
unreachable_devices();
-
- out:
- return 0;
}
-
-arch_initcall(pci_mmcfg_init);