[PATCH 3/8] x86/platform/UV: Add Support for UV4 Hubless systems

Mike Travis
2017-01-13T15:31:04Z

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Add recognition and support for UV4 hubless systems.

Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Dimitri Sivanich <sivanich@hpe.com>
Reviewed-by: Russ Anderson <rja@hpe.com>
---
arch/x86/include/asm/uv/uv.h | 2 ++
arch/x86/kernel/apic/x2apic_uv_x.c | 33 +++++++++++++++++++++++++++++++--
2 files changed, 33 insertions(+), 2 deletions(-)

--- linux.orig/arch/x86/include/asm/uv/uv.h
+++ linux/arch/x86/include/asm/uv/uv.h
@@ -10,6 +10,7 @@ struct mm_struct;

extern enum uv_system_type get_uv_system_type(void);
extern int is_uv_system(void);
+extern int is_uv_hubless(void);
extern void uv_cpu_init(void);
extern void uv_nmi_init(void);
extern void uv_system_init(void);
@@ -23,6 +24,7 @@ extern const struct cpumask *uv_flush_tl

static inline enum uv_system_type get_uv_system_type(void) { return UV_NONE; }
static inline int is_uv_system(void) { return 0; }
+static inline int is_uv_hubless(void) { return 0; }
static inline void uv_cpu_init(void) { }
static inline void uv_system_init(void) { }
static inline const struct cpumask *
--- linux.orig/arch/x86/kernel/apic/x2apic_uv_x.c
+++ linux/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -44,6 +44,7 @@ DEFINE_PER_CPU(int, x2apic_extra_bits);
#define PR_DEVEL(fmt, args...) pr_devel("%s: " fmt, __func__, args)

static enum uv_system_type uv_system_type;
+static bool uv_hubless_system;
static u64 gru_start_paddr, gru_end_paddr;
static u64 gru_dist_base, gru_first_node_paddr = -1LL, gru_last_node_paddr;
static u64 gru_dist_lmask, gru_dist_umask;
@@ -222,8 +223,14 @@ static int __init uv_acpi_madt_oem_check
int pnodeid;
int uv_apic;

- if (strncmp(oem_id, "SGI", 3) != 0)
+ if (strncmp(oem_id, "SGI", 3) != 0) {
+ if (strncmp(oem_id, "NSGI", 4) == 0) {
+ uv_hubless_system = true;
+ pr_info("UV: OEM IDs %s/%s, HUBLESS\n",
+ oem_id, oem_table_id);
+ }
return 0;
+ }

if (numa_off) {
pr_err("UV: NUMA is off, disabling UV support\n");
@@ -296,6 +303,12 @@ int is_uv_system(void)
}
EXPORT_SYMBOL_GPL(is_uv_system);

+int is_uv_hubless(void)
+{
+ return uv_hubless_system;
+}
+EXPORT_SYMBOL_GPL(is_uv_hubless);
+
void **__uv_hub_info_list;
EXPORT_SYMBOL_GPL(__uv_hub_info_list);

@@ -1365,7 +1378,7 @@ static void __init build_socket_tables(v
}
}

-void __init uv_system_init(void)
+static void __init uv_system_init_hub(void)
{
struct uv_hub_info_s hub_info = {0};
int bytes, cpu, nodeid;
@@ -1502,4 +1515,20 @@ void __init uv_system_init(void)
reboot_type = BOOT_ACPI;
}

+/*
+ * There is a small amount of UV specific code needed to initialize a
+ * UV system that does not have a "UV HUB" (referred to as "hubless").
+ */
+void __init uv_system_init(void)
+{
+ if (likely(!is_uv_system() && !is_uv_hubless()))
+ return;
+
+ /* Far more common is a standard UV system (with a HUB) */
+ if (is_uv_system())
+ uv_system_init_hub();
+
+ /* Initialize UV hubless system here */
+}
+
apic_driver(apic_x2apic_uv_x);

--