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x86/amd_nb: Add support for newer PCI topologies

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Add support for new processors which have multiple PCI root complexes
per data fabric/system management network interface.  If there are (N)
multiple PCI roots per DF/SMN interface, then the PCI roots are
redundant (as far as SMN/DF access goes).  For each DF/SMN interface:
map to the first available PCI root and skip the next N-1 PCI roots so
the following DF/SMN interface get mapped to a correct PCI root.

Ex:
DF/SMN 0 -> 60
	    40
	    20
	    00
DF/SMN 1 -> e0
	    c0
	    a0
	    80

Signed-off-by: Brian Woods <brian.woods@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Clemens Ladisch <clemens@ladisch.de>
CC: Guenter Roeck <linux@roeck-us.net>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: Jean Delvare <jdelvare@suse.com>
CC: Jia Zhang <qianyue.zj@alibaba-inc.com>
CC: <linux-hwmon@vger.kernel.org>
CC: <linux-pci@vger.kernel.org>
CC: Pu Wen <puwen@hygon.cn>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: x86-ml <x86@kernel.org>
Link: http://lkml.kernel.org/r/20181106200754.60722-3-brian.woods@amd.com
This commit is contained in:
Woods, Brian 2018-11-06 20:08:16 +00:00 committed by Borislav Petkov
parent dedf7dce4c
commit 556e4c62ba
1 changed files with 38 additions and 6 deletions
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44
arch/x86/kernel/amd_nb.c
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@ -213,7 +213,10 @@ int amd_cache_northbridges(void)
const struct pci_device_id *root_ids = amd_root_ids;
struct pci_dev *root, *misc, *link;
struct amd_northbridge *nb;
u16 i = 0;
u16 roots_per_misc = 0;
u16 misc_count = 0;
u16 root_count = 0;
u16 i, j;
if (amd_northbridges.num)
return 0;
@ -226,26 +229,55 @@ int amd_cache_northbridges(void)
misc = NULL;
while ((misc = next_northbridge(misc, misc_ids)) != NULL)
i++;
misc_count++;
if (!i)
if (!misc_count)
return -ENODEV;
nb = kcalloc(i, sizeof(struct amd_northbridge), GFP_KERNEL);
root = NULL;
while ((root = next_northbridge(root, root_ids)) != NULL)
root_count++;
if (root_count) {
roots_per_misc = root_count / misc_count;
/*
* There should be _exactly_ N roots for each DF/SMN
* interface.
*/
if (!roots_per_misc || (root_count % roots_per_misc)) {
pr_info("Unsupported AMD DF/PCI configuration found\n");
return -ENODEV;
}
}
nb = kcalloc(misc_count, sizeof(struct amd_northbridge), GFP_KERNEL);
if (!nb)
return -ENOMEM;
amd_northbridges.nb = nb;
amd_northbridges.num = i;
amd_northbridges.num = misc_count;
link = misc = root = NULL;
for (i = 0; i != amd_northbridges.num; i++) {
for (i = 0; i < amd_northbridges.num; i++) {
node_to_amd_nb(i)->root = root =
next_northbridge(root, root_ids);
node_to_amd_nb(i)->misc = misc =
next_northbridge(misc, misc_ids);
node_to_amd_nb(i)->link = link =
next_northbridge(link, link_ids);
/*
* If there are more PCI root devices than data fabric/
* system management network interfaces, then the (N)
* PCI roots per DF/SMN interface are functionally the
* same (for DF/SMN access) and N-1 are redundant. N-1
* PCI roots should be skipped per DF/SMN interface so
* the following DF/SMN interfaces get mapped to
* correct PCI roots.
*/
for (j = 1; j < roots_per_misc; j++)
root = next_northbridge(root, root_ids);
}
if (amd_gart_present())