https://github.com/torvalds/linux
Tip revision: 94f6f0550c625fab1f373bb86a6669b45e9748b3 authored by Linus Torvalds on 08 October 2023, 20:49:43 UTC
Linux 6.6-rc5
Linux 6.6-rc5
Tip revision: 94f6f05
mmconf-fam10h_64.c
// 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);
}