1 files changed, 238 insertions, 0 deletions
diff --git a/arch/x86/kernel/mmconf-fam10h_64.c b/arch/x86/kernel/mmconf-fam10h_64.c
new file mode 100644
index 000000000..c94dec6a1
--- /dev/null
+++ b/arch/x86/kernel/mmconf-fam10h_64.c
@@ -0,0 +1,238 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AMD Family 10h mmconfig enablement
+ */
+
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/pci.h>
+#include <linux/dmi.h>
+#include <linux/range.h>
+
+#include <asm/pci-direct.h>
+#include <linux/sort.h>
+#include <asm/io.h>
+#include <asm/msr.h>
+#include <asm/acpi.h>
+#include <asm/mmconfig.h>
+#include <asm/pci_x86.h>
+
+struct pci_hostbridge_probe {
+	u32 bus;
+	u32 slot;
+	u32 vendor;
+	u32 device;
+};
+
+static u64 fam10h_pci_mmconf_base;
+
+static struct pci_hostbridge_probe pci_probes[] = {
+	{ 0, 0x18, PCI_VENDOR_ID_AMD, 0x1200 },
+	{ 0xff, 0, PCI_VENDOR_ID_AMD, 0x1200 },
+};
+
+static int cmp_range(const void *x1, const void *x2)
+{
+	const struct range *r1 = x1;
+	const struct range *r2 = x2;
+	int start1, start2;
+
+	start1 = r1->start >> 32;
+	start2 = r2->start >> 32;
+
+	return start1 - start2;
+}
+
+#define MMCONF_UNIT (1ULL << FAM10H_MMIO_CONF_BASE_SHIFT)
+#define MMCONF_MASK (~(MMCONF_UNIT - 1))
+#define MMCONF_SIZE (MMCONF_UNIT << 8)
+/* need to avoid (0xfd<<32), (0xfe<<32), and (0xff<<32), ht used space */
+#define FAM10H_PCI_MMCONF_BASE (0xfcULL<<32)
+#define BASE_VALID(b) ((b) + MMCONF_SIZE <= (0xfdULL<<32) || (b) >= (1ULL<<40))
+static void get_fam10h_pci_mmconf_base(void)
+{
+	int i;
+	unsigned bus;
+	unsigned slot;
+	int found;
+
+	u64 val;
+	u32 address;
+	u64 tom2;
+	u64 base = FAM10H_PCI_MMCONF_BASE;
+
+	int hi_mmio_num;
+	struct range range[8];
+
+	/* only try to get setting from BSP */
+	if (fam10h_pci_mmconf_base)
+		return;
+
+	if (!early_pci_allowed())
+		return;
+
+	found = 0;
+	for (i = 0; i < ARRAY_SIZE(pci_probes); i++) {
+		u32 id;
+		u16 device;
+		u16 vendor;
+
+		bus = pci_probes[i].bus;
+		slot = pci_probes[i].slot;
+		id = read_pci_config(bus, slot, 0, PCI_VENDOR_ID);
+
+		vendor = id & 0xffff;
+		device = (id>>16) & 0xffff;
+		if (pci_probes[i].vendor == vendor &&
+		    pci_probes[i].device == device) {
+			found = 1;
+			break;
+		}
+	}
+
+	if (!found)
+		return;
+
+	/* SYS_CFG */
+	address = MSR_AMD64_SYSCFG;
+	rdmsrl(address, val);
+
+	/* TOP_MEM2 is not enabled? */
+	if (!(val & (1<<21))) {
+		tom2 = 1ULL << 32;
+	} else {
+		/* TOP_MEM2 */
+		address = MSR_K8_TOP_MEM2;
+		rdmsrl(address, val);
+		tom2 = max(val & 0xffffff800000ULL, 1ULL << 32);
+	}
+
+	if (base <= tom2)
+		base = (tom2 + 2 * MMCONF_UNIT - 1) & MMCONF_MASK;
+
+	/*
+	 * need to check if the range is in the high mmio range that is
+	 * above 4G
+	 */
+	hi_mmio_num = 0;
+	for (i = 0; i < 8; i++) {
+		u32 reg;
+		u64 start;
+		u64 end;
+		reg = read_pci_config(bus, slot, 1, 0x80 + (i << 3));
+		if (!(reg & 3))
+			continue;
+
+		start = (u64)(reg & 0xffffff00) << 8; /* 39:16 on 31:8*/
+		reg = read_pci_config(bus, slot, 1, 0x84 + (i << 3));
+		end = ((u64)(reg & 0xffffff00) << 8) | 0xffff; /* 39:16 on 31:8*/
+
+		if (end < tom2)
+			continue;
+
+		range[hi_mmio_num].start = start;
+		range[hi_mmio_num].end = end;
+		hi_mmio_num++;
+	}
+
+	if (!hi_mmio_num)
+		goto out;
+
+	/* sort the range */
+	sort(range, hi_mmio_num, sizeof(struct range), cmp_range, NULL);
+
+	if (range[hi_mmio_num - 1].end < base)
+		goto out;
+	if (range[0].start > base + MMCONF_SIZE)
+		goto out;
+
+	/* need to find one window */
+	base = (range[0].start & MMCONF_MASK) - MMCONF_UNIT;
+	if ((base > tom2) && BASE_VALID(base))
+		goto out;
+	base = (range[hi_mmio_num - 1].end + MMCONF_UNIT) & MMCONF_MASK;
+	if (BASE_VALID(base))
+		goto out;
+	/* need to find window between ranges */
+	for (i = 1; i < hi_mmio_num; i++) {
+		base = (range[i - 1].end + MMCONF_UNIT) & MMCONF_MASK;
+		val = range[i].start & MMCONF_MASK;
+		if (val >= base + MMCONF_SIZE && BASE_VALID(base))
+			goto out;
+	}
+	return;
+
+out:
+	fam10h_pci_mmconf_base = base;
+}
+
+void fam10h_check_enable_mmcfg(void)
+{
+	u64 val;
+	u32 address;
+
+	if (!(pci_probe & PCI_CHECK_ENABLE_AMD_MMCONF))
+		return;
+
+	address = MSR_FAM10H_MMIO_CONF_BASE;
+	rdmsrl(address, val);
+
+	/* try to make sure that AP's setting is identical to BSP setting */
+	if (val & FAM10H_MMIO_CONF_ENABLE) {
+		unsigned busnbits;
+		busnbits = (val >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
+			FAM10H_MMIO_CONF_BUSRANGE_MASK;
+
+		/* only trust the one handle 256 buses, if acpi=off */
+		if (!acpi_pci_disabled || busnbits >= 8) {
+			u64 base = val & MMCONF_MASK;
+
+			if (!fam10h_pci_mmconf_base) {
+				fam10h_pci_mmconf_base = base;
+				return;
+			} else if (fam10h_pci_mmconf_base ==  base)
+				return;
+		}
+	}
+
+	/*
+	 * if it is not enabled, try to enable it and assume only one segment
+	 * with 256 buses
+	 */
+	get_fam10h_pci_mmconf_base();
+	if (!fam10h_pci_mmconf_base) {
+		pci_probe &= ~PCI_CHECK_ENABLE_AMD_MMCONF;
+		return;
+	}
+
+	printk(KERN_INFO "Enable MMCONFIG on AMD Family 10h\n");
+	val &= ~((FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT) |
+	     (FAM10H_MMIO_CONF_BUSRANGE_MASK<<FAM10H_MMIO_CONF_BUSRANGE_SHIFT));
+	val |= fam10h_pci_mmconf_base | (8 << FAM10H_MMIO_CONF_BUSRANGE_SHIFT) |
+	       FAM10H_MMIO_CONF_ENABLE;
+	wrmsrl(address, val);
+}
+
+static int __init set_check_enable_amd_mmconf(const struct dmi_system_id *d)
+{
+        pci_probe |= PCI_CHECK_ENABLE_AMD_MMCONF;
+        return 0;
+}
+
+static const struct dmi_system_id __initconst mmconf_dmi_table[] = {
+        {
+                .callback = set_check_enable_amd_mmconf,
+                .ident = "Sun Microsystems Machine",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "Sun Microsystems"),
+                },
+        },
+	{}
+};
+
+/* Called from a non __init function, but only on the BSP. */
+void __ref check_enable_amd_mmconf_dmi(void)
+{
+	dmi_check_system(mmconf_dmi_table);
+}