[PATCH 15/21] X86_64, UV: Add UV4 addressing discovery function

From: Mike Travis
Date: Wed Apr 27 2016 - 21:12:55 EST


UV4 requires early system wide addressing values. This involves the use
of the CPUID instruction to obtain these values. The current function
(detect_extended_topology()) in the kernel has been copied and streamlined,
with the limitation that only CPU's used by UV architectures are supported.

Signed-off-by: Mike Travis <travis@xxxxxxx>
Reviewed-by: Dimitri Sivanich <sivanich@xxxxxxx>
Tested-by: John Estabrook <estabrook@xxxxxxx>
Tested-by: Gary Kroening <gfk@xxxxxxx>
---
arch/x86/kernel/apic/x2apic_uv_x.c | 85 +++++++++++++++++++++++++++++++------
1 file changed, 72 insertions(+), 13 deletions(-)

--- linux.orig/arch/x86/kernel/apic/x2apic_uv_x.c
+++ linux/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -46,6 +46,16 @@ static u64 gru_start_paddr, gru_end_padd
static u64 gru_dist_base, gru_first_node_paddr = -1LL, gru_last_node_paddr;
static u64 gru_dist_lmask, gru_dist_umask;
static union uvh_apicid uvh_apicid;
+
+/* info derived from CPUID */
+static struct {
+ unsigned int apicid_shift;
+ unsigned int apicid_mask;
+ unsigned int socketid_shift; /* aka pnode_shift for UV1/2/3 */
+ unsigned int pnode_mask;
+ unsigned int gpa_shift;
+} uv_cpuid;
+
int uv_min_hub_revision_id;
EXPORT_SYMBOL_GPL(uv_min_hub_revision_id);

@@ -123,18 +133,65 @@ static int __init early_get_pnodeid(void
}

uv_hub_info->hub_revision = uv_min_hub_revision_id;
- pnode = (node_id.s.node_id >> 1) & ((1 << m_n_config.s.n_skt) - 1);
+ uv_cpuid.pnode_mask = (1 << m_n_config.s.n_skt) - 1;
+ pnode = (node_id.s.node_id >> 1) & uv_cpuid.pnode_mask;
+ uv_cpuid.gpa_shift = 46; /* default unless changed */
+
+ pr_info("UV: rev:%d part#:%x nodeid:%04x n_skt:%d pnmsk:%x pn:%x\n",
+ node_id.s.revision, node_id.s.part_number, node_id.s.node_id,
+ m_n_config.s.n_skt, uv_cpuid.pnode_mask, pnode);
return pnode;
}

-static void __init early_get_apic_pnode_shift(void)
+/* [copied from arch/x86/kernel/cpu/topology.c:detect_extended_topology()] */
+#define SMT_LEVEL 0 /* leaf 0xb SMT level */
+#define INVALID_TYPE 0 /* leaf 0xb sub-leaf types */
+#define SMT_TYPE 1
+#define CORE_TYPE 2
+#define LEAFB_SUBTYPE(ecx) (((ecx) >> 8) & 0xff)
+#define BITS_SHIFT_NEXT_LEVEL(eax) ((eax) & 0x1f)
+
+static void set_x2apic_bits(void)
+{
+ unsigned int eax, ebx, ecx, edx, sub_index;
+ unsigned int sid_shift;
+
+ cpuid(0, &eax, &ebx, &ecx, &edx);
+ if (eax < 0xb) {
+ pr_info("UV: CPU does not have CPUID.11\n");
+ return;
+ }
+ cpuid_count(0xb, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
+ if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE)) {
+ pr_info("UV: CPUID.11 not implemented\n");
+ return;
+ }
+ sid_shift = BITS_SHIFT_NEXT_LEVEL(eax);
+ sub_index = 1;
+ do {
+ cpuid_count(0xb, sub_index, &eax, &ebx, &ecx, &edx);
+ if (LEAFB_SUBTYPE(ecx) == CORE_TYPE) {
+ sid_shift = BITS_SHIFT_NEXT_LEVEL(eax);
+ break;
+ }
+ sub_index++;
+ } while (LEAFB_SUBTYPE(ecx) != INVALID_TYPE);
+ uv_cpuid.apicid_shift = 0;
+ uv_cpuid.apicid_mask = (~(-1 << sid_shift));
+ uv_cpuid.socketid_shift = sid_shift;
+}
+
+static void __init early_get_apic_socketid_shift(void)
{
- uvh_apicid.v = uv_early_read_mmr(UVH_APICID);
- if (!uvh_apicid.v)
- /*
- * Old bios, use default value
- */
- uvh_apicid.s.pnode_shift = UV_APIC_PNODE_SHIFT;
+ if (is_uv2_hub() || is_uv3_hub())
+ uvh_apicid.v = uv_early_read_mmr(UVH_APICID);
+
+ set_x2apic_bits();
+
+ pr_info("UV: apicid_shift:%d apicid_mask:0x%x\n",
+ uv_cpuid.apicid_shift, uv_cpuid.apicid_mask);
+ pr_info("UV: socketid_shift:%d pnode_mask:0x%x\n",
+ uv_cpuid.socketid_shift, uv_cpuid.pnode_mask);
}

static int __init uv_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
@@ -165,7 +222,7 @@ static int __init uv_acpi_madt_oem_check
goto badbios;

pnodeid = early_get_pnodeid();
- early_get_apic_pnode_shift();
+ early_get_apic_socketid_shift();
x86_platform.is_untracked_pat_range = uv_is_untracked_pat_range;
x86_platform.nmi_init = uv_nmi_init;

@@ -877,11 +934,13 @@ void __init uv_init_hub_info(struct uv_h
hub_info->m_val = mn.m_val;
hub_info->n_val = mn.n_val;
hub_info->m_shift = mn.m_shift;
- hub_info->n_lshift = mn.n_lshift;
+ hub_info->n_lshift = mn.n_lshift ? mn.n_lshift : 0;

hub_info->hub_revision = uv_hub_info->hub_revision;
- hub_info->pnode_mask = (1 << mn.n_val) - 1;
- hub_info->gpa_mask = (1UL << (mn.m_val + mn.n_val)) - 1;
+ hub_info->pnode_mask = uv_cpuid.pnode_mask;
+ hub_info->gpa_mask = mn.m_val ?
+ (1UL << (mn.m_val + mn.n_val)) - 1 :
+ (1UL << uv_cpuid.gpa_shift) - 1;

node_id.v = uv_read_local_mmr(UVH_NODE_ID);
hub_info->gnode_extra =
@@ -897,7 +956,7 @@ void __init uv_init_hub_info(struct uv_h
get_lowmem_redirect(
&hub_info->lowmem_remap_base, &hub_info->lowmem_remap_top);

- hub_info->apic_pnode_shift = uvh_apicid.s.pnode_shift;
+ hub_info->apic_pnode_shift = uv_cpuid.socketid_shift;

/* show system specific info */
pr_info("UV: N:%d M:%d m_shift:%d n_lshift:%d\n",

--