x86/PCI: host mmconfig detect clean up

Fix mmconfig detection to not assume a single mmconfig space in the
northbridge, paving the way for AMD fam10h + mcp55 CPUs.  On those, the
MSR has some range, but the mcp55 pci config will have another one.

Also helps the mcp55 + io55 case, where every one will have one range.

If it is mcp55, exclude the range that is used by CPU MSR, in other
words , if the CPU claims busses 0-255, the range in mcp55 is dropped,
because CPU HW will not route those ranges to mcp55 mmconfig to handle
it.

Signed-off-by: Yinghai Lu <yinghai.lu@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

2 files changed, 120 insertions, 60 deletions

diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c
index d68dc1bb01b..905bb526b13 100644
--- a/arch/x86/pci/mmconfig-shared.c
+++ b/arch/x86/pci/mmconfig-shared.c
@@ -14,6 +14,7 @@
 #include <linux/init.h>
 #include <linux/acpi.h>
 #include <linux/bitmap.h>
+#include <linux/sort.h>
 #include <asm/e820.h>
 #include <asm/pci_x86.h>
 
@@ -24,24 +25,49 @@
 /* Indicate if the mmcfg resources have been placed into the resource table. */
 static int __initdata pci_mmcfg_resources_inserted;
 
+static __init int extend_mmcfg(int num)
+{
+        struct acpi_mcfg_allocation *new;
+        int new_num = pci_mmcfg_config_num + num;
+
+        new = kzalloc(sizeof(pci_mmcfg_config[0]) * new_num, GFP_KERNEL);
+        if (!new)
+                return -1;
+
+        if (pci_mmcfg_config) {
+                memcpy(new, pci_mmcfg_config,
+                         sizeof(pci_mmcfg_config[0]) * new_num);
+                kfree(pci_mmcfg_config);
+        }
+        pci_mmcfg_config = new;
+
+        return 0;
+}
+
+static __init void fill_one_mmcfg(u64 addr, int segment, int start, int end)
+{
+        int i = pci_mmcfg_config_num;
+
+        pci_mmcfg_config_num++;
+        pci_mmcfg_config[i].address = addr;
+        pci_mmcfg_config[i].pci_segment = segment;
+        pci_mmcfg_config[i].start_bus_number = start;
+        pci_mmcfg_config[i].end_bus_number = end;
+}
+
 static const char __init *pci_mmcfg_e7520(void)
 {
         u32 win;
         raw_pci_ops->read(0, 0, PCI_DEVFN(0, 0), 0xce, 2, &win);
 
         win = win & 0xf000;
-        if(win == 0x0000 || win == 0xf000)
-                pci_mmcfg_config_num = 0;
-        else {
-                pci_mmcfg_config_num = 1;
-                pci_mmcfg_config = kzalloc(sizeof(pci_mmcfg_config[0]), GFP_KERNEL);
-                if (!pci_mmcfg_config)
-                        return NULL;
-                pci_mmcfg_config[0].address = win << 16;
-                pci_mmcfg_config[0].pci_segment = 0;
-                pci_mmcfg_config[0].start_bus_number = 0;
-                pci_mmcfg_config[0].end_bus_number = 255;
-        }
+        if (win == 0x0000 || win == 0xf000)
+                return NULL;
+
+        if (extend_mmcfg(1) == -1)
+                return NULL;
+
+        fill_one_mmcfg(win << 16, 0, 0, 255);
 
         return "Intel Corporation E7520 Memory Controller Hub";
 }
@@ -50,13 +76,11 @@ static const char __init *pci_mmcfg_intel_945(void)
 {
         u32 pciexbar, mask = 0, len = 0;
 
-        pci_mmcfg_config_num = 1;
-
         raw_pci_ops->read(0, 0, PCI_DEVFN(0, 0), 0x48, 4, &pciexbar);
 
         /* Enable bit */
         if (!(pciexbar & 1))
-                pci_mmcfg_config_num = 0;
+                return NULL;
 
         /* Size bits */
         switch ((pciexbar >> 1) & 3) {
@@ -73,28 +97,23 @@ static const char __init *pci_mmcfg_intel_945(void)
                 len  = 0x04000000U;
                 break;
         default:
-                pci_mmcfg_config_num = 0;
+                return NULL;
         }
 
         /* Errata #2, things break when not aligned on a 256Mb boundary */
         /* Can only happen in 64M/128M mode */
 
         if ((pciexbar & mask) & 0x0fffffffU)
-                pci_mmcfg_config_num = 0;
+                return NULL;
 
         /* Don't hit the APIC registers and their friends */
         if ((pciexbar & mask) >= 0xf0000000U)
-                pci_mmcfg_config_num = 0;
-
-        if (pci_mmcfg_config_num) {
-                pci_mmcfg_config = kzalloc(sizeof(pci_mmcfg_config[0]), GFP_KERNEL);
-                if (!pci_mmcfg_config)
-                        return NULL;
-                pci_mmcfg_config[0].address = pciexbar & mask;
-                pci_mmcfg_config[0].pci_segment = 0;
-                pci_mmcfg_config[0].start_bus_number = 0;
-                pci_mmcfg_config[0].end_bus_number = (len >> 20) - 1;
-        }
+                return NULL;
+
+        if (extend_mmcfg(1) == -1)
+                return NULL;
+
+        fill_one_mmcfg(pciexbar & mask, 0, 0, (len >> 20) - 1);
 
         return "Intel Corporation 945G/GZ/P/PL Express Memory Controller Hub";
 }
@@ -138,18 +157,11 @@ static const char __init *pci_mmcfg_amd_fam10h(void)
                 busnbits = 8;
         }
 
-        pci_mmcfg_config_num = (1 << segnbits);
-        pci_mmcfg_config = kzalloc(sizeof(pci_mmcfg_config[0]) *
-                                   pci_mmcfg_config_num, GFP_KERNEL);
-        if (!pci_mmcfg_config)
+        if (extend_mmcfg(1 << segnbits) == -1)
                 return NULL;
 
-        for (i = 0; i < (1 << segnbits); i++) {
-                pci_mmcfg_config[i].address = base + (1<<28) * i;
-                pci_mmcfg_config[i].pci_segment = i;
-                pci_mmcfg_config[i].start_bus_number = 0;
-                pci_mmcfg_config[i].end_bus_number = (1 << busnbits) - 1;
-        }
+        for (i = 0; i < (1 << segnbits); i++)
+                fill_one_mmcfg(base + (1<<28) * i, i, 0, (1 << busnbits) - 1);
 
         return "AMD Family 10h NB";
 }
@@ -237,6 +249,48 @@ static struct pci_mmcfg_hostbridge_probe pci_mmcfg_probes[] __initdata = {
           0x0369, pci_mmcfg_nvidia_mcp55 },
 };
 
+static int __init cmp_mmcfg(const void *x1, const void *x2)
+{
+        const typeof(pci_mmcfg_config[0]) *m1 = x1;
+        const typeof(pci_mmcfg_config[0]) *m2 = x2;
+        int start1, start2;
+
+        start1 = m1->start_bus_number;
+        start2 = m2->start_bus_number;
+
+        return start1 - start2;
+}
+
+static void __init pci_mmcfg_check_end_bus_number(void)
+{
+        int i;
+        typeof(pci_mmcfg_config[0]) *cfg, *cfgx;
+
+        /* sort them at first */
+        sort(pci_mmcfg_config, pci_mmcfg_config_num,
+                 sizeof(pci_mmcfg_config[0]), cmp_mmcfg, NULL);
+
+        /* last one*/
+        if (pci_mmcfg_config_num > 0) {
+                i = pci_mmcfg_config_num - 1;
+                cfg = &pci_mmcfg_config[i];
+                if (cfg->end_bus_number < cfg->start_bus_number)
+                        cfg->end_bus_number = 255;
+        }
+
+        /* don't overlap please */
+        for (i = 0; i < pci_mmcfg_config_num - 1; i++) {
+                cfg = &pci_mmcfg_config[i];
+                cfgx = &pci_mmcfg_config[i+1];
+
+                if (cfg->end_bus_number < cfg->start_bus_number)
+                        cfg->end_bus_number = 255;
+
+                if (cfg->end_bus_number >= cfgx->start_bus_number)
+                        cfg->end_bus_number = cfgx->start_bus_number - 1;
+        }
+}
+
 static int __init pci_mmcfg_check_hostbridge(void)
 {
         u32 l;
@@ -250,31 +304,33 @@ static int __init pci_mmcfg_check_hostbridge(void)
 
         pci_mmcfg_config_num = 0;
         pci_mmcfg_config = NULL;
-        name = NULL;
 
-        for (i = 0; !name && i < ARRAY_SIZE(pci_mmcfg_probes); i++) {
+        for (i = 0; i < ARRAY_SIZE(pci_mmcfg_probes); i++) {
                 bus =  pci_mmcfg_probes[i].bus;
                 devfn = pci_mmcfg_probes[i].devfn;
                 raw_pci_ops->read(0, bus, devfn, 0, 4, &l);
                 vendor = l & 0xffff;
                 device = (l >> 16) & 0xffff;
 
+                name = NULL;
                 if (pci_mmcfg_probes[i].vendor == vendor &&
                     pci_mmcfg_probes[i].device == device)
                         name = pci_mmcfg_probes[i].probe();
-        }
 
-        if (name) {
-                printk(KERN_INFO "PCI: Found %s %s MMCONFIG support.\n",
-                       name, pci_mmcfg_config_num ? "with" : "without");
+                if (name)
+                        printk(KERN_INFO "PCI: Found %s with MMCONFIG support.\n",
+                               name);
         }
 
-        return name != NULL;
+        /* some end_bus_number is crazy, fix it */
+        pci_mmcfg_check_end_bus_number();
+
+        return pci_mmcfg_config_num != 0;
 }
 
 static void __init pci_mmcfg_insert_resources(void)
 {
-#define PCI_MMCFG_RESOURCE_NAME_LEN 19
+#define PCI_MMCFG_RESOURCE_NAME_LEN 24
         int i;
         struct resource *res;
         char *names;
@@ -292,9 +348,10 @@ static void __init pci_mmcfg_insert_resources(void)
                 struct acpi_mcfg_allocation *cfg = &pci_mmcfg_config[i];
                 num_buses = cfg->end_bus_number - cfg->start_bus_number + 1;
                 res->name = names;
-                snprintf(names, PCI_MMCFG_RESOURCE_NAME_LEN, "PCI MMCONFIG %u",
-                         cfg->pci_segment);
-                res->start = cfg->address;
+                snprintf(names, PCI_MMCFG_RESOURCE_NAME_LEN,
+                         "PCI MMCONFIG %u [%02x-%02x]", cfg->pci_segment,
+                         cfg->start_bus_number, cfg->end_bus_number);
+                res->start = cfg->address + (cfg->start_bus_number << 20);
                 res->end = res->start + (num_buses << 20) - 1;
                 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
                 insert_resource(&iomem_resource, res);
@@ -418,8 +475,6 @@ static void __init pci_mmcfg_reject_broken(int early)
             (pci_mmcfg_config[0].address == 0))
                 return;
 
-        cfg = &pci_mmcfg_config[0];
-
         for (i = 0; i < pci_mmcfg_config_num; i++) {
                 int valid = 0;
                 u64 addr, size;
@@ -487,10 +542,10 @@ static void __init __pci_mmcfg_init(int early)
                         known_bridge = 1;
         }
 
-        if (!known_bridge) {
+        if (!known_bridge)
                 acpi_table_parse(ACPI_SIG_MCFG, acpi_parse_mcfg);
-                pci_mmcfg_reject_broken(early);
-        }
+
+        pci_mmcfg_reject_broken(early);
 
         if ((pci_mmcfg_config_num == 0) ||
             (pci_mmcfg_config == NULL) ||
diff --git a/arch/x86/pci/mmconfig_64.c b/arch/x86/pci/mmconfig_64.c
index 30007ffc8e1..94349f8b2f9 100644
--- a/arch/x86/pci/mmconfig_64.c
+++ b/arch/x86/pci/mmconfig_64.c
@@ -112,13 +112,18 @@ static struct pci_raw_ops pci_mmcfg = {
 static void __iomem * __init mcfg_ioremap(struct acpi_mcfg_allocation *cfg)
 {
         void __iomem *addr;
-        u32 size;
-
-        size = (cfg->end_bus_number + 1) << 20;
-        addr = ioremap_nocache(cfg->address, size);
+        u64 start, size;
+
+        start = cfg->start_bus_number;
+        start <<= 20;
+        start += cfg->address;
+        size = cfg->end_bus_number + 1 - cfg->start_bus_number;
+        size <<= 20;
+        addr = ioremap_nocache(start, size);
         if (addr) {
                 printk(KERN_INFO "PCI: Using MMCONFIG at %Lx - %Lx\n",
-                       cfg->address, cfg->address + size - 1);
+                       start, start + size - 1);
+                addr -= cfg->start_bus_number << 20;
         }
         return addr;
 }
@@ -157,7 +162,7 @@ void __init pci_mmcfg_arch_free(void)
 
         for (i = 0; i < pci_mmcfg_config_num; ++i) {
                 if (pci_mmcfg_virt[i].virt) {
-                        iounmap(pci_mmcfg_virt[i].virt);
+                        iounmap(pci_mmcfg_virt[i].virt + (pci_mmcfg_virt[i].cfg->start_bus_number << 20));
                         pci_mmcfg_virt[i].virt = NULL;
                         pci_mmcfg_virt[i].cfg = NULL;
                 }