#include <linux/pci.h>
#include <linux/init.h>
+#include <linux/acpi.h>
+#include <linux/bitmap.h>
+#include <asm/e820.h>
+
#include "pci.h"
-#define MMCONFIG_APER_SIZE (256*1024*1024)
+/* aperture is up to 256MB but BIOS may reserve less */
+#define MMCONFIG_APER_MIN (2 * 1024*1024)
+#define MMCONFIG_APER_MAX (256 * 1024*1024)
+
+/* Verify the first 16 busses. We assume that systems with more busses
+ get MCFG right. */
+#define MAX_CHECK_BUS 16
-/* The physical address of the MMCONFIG aperture. Set from ACPI tables. */
-u32 pci_mmcfg_base_addr;
+static DECLARE_BITMAP(fallback_slots, 32*MAX_CHECK_BUS);
/* Static virtual mapping of the MMCONFIG aperture */
-char *pci_mmcfg_virt;
+struct mmcfg_virt {
+ struct acpi_table_mcfg_config *cfg;
+ char __iomem *virt;
+};
+static struct mmcfg_virt *pci_mmcfg_virt;
+
+static char __iomem *get_virt(unsigned int seg, unsigned bus)
+{
+ int cfg_num = -1;
+ struct acpi_table_mcfg_config *cfg;
+
+ while (1) {
+ ++cfg_num;
+ if (cfg_num >= pci_mmcfg_config_num)
+ break;
+ cfg = pci_mmcfg_virt[cfg_num].cfg;
+ if (cfg->pci_segment_group_number != seg)
+ continue;
+ if ((cfg->start_bus_number <= bus) &&
+ (cfg->end_bus_number >= bus))
+ return pci_mmcfg_virt[cfg_num].virt;
+ }
-static inline char *pci_dev_base(int bus, int devfn)
+ /* Handle more broken MCFG tables on Asus etc.
+ They only contain a single entry for bus 0-0. Assume
+ this applies to all busses. */
+ cfg = &pci_mmcfg_config[0];
+ if (pci_mmcfg_config_num == 1 &&
+ cfg->pci_segment_group_number == 0 &&
+ (cfg->start_bus_number | cfg->end_bus_number) == 0)
+ return pci_mmcfg_virt[0].virt;
+
+ /* Fall back to type 0 */
+ return NULL;
+}
+
+static char __iomem *pci_dev_base(unsigned int seg, unsigned int bus, unsigned int devfn)
{
- return pci_mmcfg_virt + ((bus << 20) | (devfn << 12));
+ char __iomem *addr;
+ if (seg == 0 && bus < MAX_CHECK_BUS &&
+ test_bit(32*bus + PCI_SLOT(devfn), fallback_slots))
+ return NULL;
+ addr = get_virt(seg, bus);
+ if (!addr)
+ return NULL;
+ return addr + ((bus << 20) | (devfn << 12));
}
-static int pci_mmcfg_read(int seg, int bus, int devfn, int reg, int len, u32 *value)
+static int pci_mmcfg_read(unsigned int seg, unsigned int bus,
+ unsigned int devfn, int reg, int len, u32 *value)
{
- char *addr = pci_dev_base(bus, devfn);
+ char __iomem *addr;
- if (unlikely(!value || (bus > 255) || (devfn > 255) || (reg > 4095)))
+ /* Why do we have this when nobody checks it. How about a BUG()!? -AK */
+ if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) {
+ *value = -1;
return -EINVAL;
+ }
+
+ addr = pci_dev_base(seg, bus, devfn);
+ if (!addr)
+ return pci_conf1_read(seg,bus,devfn,reg,len,value);
switch (len) {
case 1:
return 0;
}
-static int pci_mmcfg_write(int seg, int bus, int devfn, int reg, int len, u32 value)
+static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
+ unsigned int devfn, int reg, int len, u32 value)
{
- char *addr = pci_dev_base(bus,devfn);
+ char __iomem *addr;
+ /* Why do we have this when nobody checks it. How about a BUG()!? -AK */
if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095)))
return -EINVAL;
+ addr = pci_dev_base(seg, bus, devfn);
+ if (!addr)
+ return pci_conf1_write(seg,bus,devfn,reg,len,value);
+
switch (len) {
case 1:
writeb(value, addr + reg);
.write = pci_mmcfg_write,
};
-static int __init pci_mmcfg_init(void)
+/* K8 systems have some devices (typically in the builtin northbridge)
+ that are only accessible using type1
+ 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. */
+static __init void unreachable_devices(void)
{
+ int i, k;
+ /* Use the max bus number from ACPI here? */
+ for (k = 0; k < MAX_CHECK_BUS; k++) {
+ for (i = 0; i < 32; i++) {
+ u32 val1;
+ char __iomem *addr;
+
+ pci_conf1_read(0, k, PCI_DEVFN(i,0), 0, 4, &val1);
+ if (val1 == 0xffffffff)
+ continue;
+ addr = pci_dev_base(0, k, PCI_DEVFN(i, 0));
+ if (addr == NULL|| readl(addr) != val1) {
+ set_bit(i + 32*k, fallback_slots);
+ printk(KERN_NOTICE
+ "PCI: No mmconfig possible on device %x:%x\n",
+ k, i);
+ }
+ }
+ }
+}
+
+void __init pci_mmcfg_init(void)
+{
+ int i;
+
if ((pci_probe & PCI_PROBE_MMCONF) == 0)
- return 0;
- if (!pci_mmcfg_base_addr)
- return 0;
+ 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))
+ return;
+
+ if (!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;
+ }
/* RED-PEN i386 doesn't do _nocache right now */
- pci_mmcfg_virt = ioremap_nocache(pci_mmcfg_base_addr, MMCONFIG_APER_SIZE);
- if (!pci_mmcfg_virt) {
- printk("PCI: Cannot map mmconfig aperture\n");
- return 0;
- }
+ pci_mmcfg_virt = kmalloc(sizeof(*pci_mmcfg_virt) * pci_mmcfg_config_num, GFP_KERNEL);
+ if (pci_mmcfg_virt == NULL) {
+ printk("PCI: Can not allocate memory for mmconfig structures\n");
+ return;
+ }
+ for (i = 0; i < pci_mmcfg_config_num; ++i) {
+ pci_mmcfg_virt[i].cfg = &pci_mmcfg_config[i];
+ pci_mmcfg_virt[i].virt = ioremap_nocache(pci_mmcfg_config[i].base_address,
+ MMCONFIG_APER_MAX);
+ if (!pci_mmcfg_virt[i].virt) {
+ printk("PCI: Cannot map mmconfig aperture for segment %d\n",
+ pci_mmcfg_config[i].pci_segment_group_number);
+ return;
+ }
+ printk(KERN_INFO "PCI: Using MMCONFIG at %x\n", pci_mmcfg_config[i].base_address);
+ }
+
+ unreachable_devices();
- printk(KERN_INFO "PCI: Using MMCONFIG at %x\n", pci_mmcfg_base_addr);
raw_pci_ops = &pci_mmcfg;
pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
-
- return 0;
}
-
-arch_initcall(pci_mmcfg_init);