sgi-xp: prepare xpc_rsvd_page to work on either sn2 or uv hardware
Prepare XPC's reserved page header to work for either sn2 or uv.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/misc/sgi-xp/Makefile b/drivers/misc/sgi-xp/Makefile
index b50f292..b3eeff3 100644
--- a/drivers/misc/sgi-xp/Makefile
+++ b/drivers/misc/sgi-xp/Makefile
@@ -7,6 +7,7 @@
xp-$(CONFIG_IA64) += xp_sn2.o xp_nofault.o
obj-$(CONFIG_SGI_XP) += xpc.o
-xpc-y := xpc_main.o xpc_channel.o xpc_partition.o
+xpc-y := xpc_main.o xpc_uv.o xpc_channel.o xpc_partition.o
+xpc-$(CONFIG_IA64) += xpc_sn2.o
obj-$(CONFIG_SGI_XP) += xpnet.o
diff --git a/drivers/misc/sgi-xp/xp.h b/drivers/misc/sgi-xp/xp.h
index c42196a..0f75592 100644
--- a/drivers/misc/sgi-xp/xp.h
+++ b/drivers/misc/sgi-xp/xp.h
@@ -220,9 +220,10 @@
xpBteCopyError, /* 52: bte_copy() returned error */
xpSalError, /* 53: sn SAL error */
+ xpRsvdPageNotSet, /* 54: the reserved page is not set up */
- xpUnsupported, /* 54: unsupported functionality or resource */
- xpUnknownReason /* 55: unknown reason - must be last in enum */
+ xpUnsupported, /* 55: unsupported functionality or resource */
+ xpUnknownReason /* 56: unknown reason - must be last in enum */
};
/*
diff --git a/drivers/misc/sgi-xp/xpc.h b/drivers/misc/sgi-xp/xpc.h
index 60388be..94b52bb 100644
--- a/drivers/misc/sgi-xp/xpc.h
+++ b/drivers/misc/sgi-xp/xpc.h
@@ -71,11 +71,11 @@
*
* reserved page header
*
- * The first cacheline of the reserved page contains the header
- * (struct xpc_rsvd_page). Before SAL initialization has completed,
+ * The first two 64-byte cachelines of the reserved page contain the
+ * header (struct xpc_rsvd_page). Before SAL initialization has completed,
* SAL has set up the following fields of the reserved page header:
- * SAL_signature, SAL_version, partid, and nasids_size. The other
- * fields are set up by XPC. (xpc_rsvd_page points to the local
+ * SAL_signature, SAL_version, SAL_partid, and SAL_nasids_size. The
+ * other fields are set up by XPC. (xpc_rsvd_page points to the local
* partition's reserved page.)
*
* part_nasids mask
@@ -89,11 +89,11 @@
* nasids. The part_nasids mask is located starting at the first cacheline
* following the reserved page header. The mach_nasids mask follows right
* after the part_nasids mask. The size in bytes of each mask is reflected
- * by the reserved page header field 'nasids_size'. (Local partition's
+ * by the reserved page header field 'SAL_nasids_size'. (Local partition's
* mask pointers are xpc_part_nasids and xpc_mach_nasids.)
*
- * vars
- * vars part
+ * vars (ia64-sn2 only)
+ * vars part (ia64-sn2 only)
*
* Immediately following the mach_nasids mask are the XPC variables
* required by other partitions. First are those that are generic to all
@@ -101,25 +101,31 @@
* which are partition specific (vars part). These are setup by XPC.
* (Local partition's vars pointers are xpc_vars and xpc_vars_part.)
*
- * Note: Until vars_pa is set, the partition XPC code has not been initialized.
+ * Note: Until 'stamp' is set non-zero, the partition XPC code has not been
+ * initialized.
*/
struct xpc_rsvd_page {
u64 SAL_signature; /* SAL: unique signature */
u64 SAL_version; /* SAL: version */
- u8 partid; /* SAL: partition ID */
+ short SAL_partid; /* SAL: partition ID */
+ short max_npartitions; /* value of XPC_MAX_PARTITIONS */
u8 version;
- u8 pad1[6]; /* align to next u64 in cacheline */
- u64 vars_pa; /* physical address of struct xpc_vars */
+ u8 pad1[3]; /* align to next u64 in 1st 64-byte cacheline */
+ union {
+ u64 vars_pa; /* physical address of struct xpc_vars */
+ u64 activate_mq_gpa; /* global phys address of activate_mq */
+ } sn;
struct timespec stamp; /* time when reserved page was setup by XPC */
- u64 pad2[9]; /* align to last u64 in cacheline */
- u64 nasids_size; /* SAL: size of each nasid mask in bytes */
+ u64 pad2[9]; /* align to last u64 in 2nd 64-byte cacheline */
+ u64 SAL_nasids_size; /* SAL: size of each nasid mask in bytes */
};
-#define XPC_RP_VERSION _XPC_VERSION(1, 1) /* version 1.1 of the reserved page */
+#define XPC_RP_VERSION _XPC_VERSION(2, 0) /* version 2.0 of the reserved page */
#define XPC_SUPPORTS_RP_STAMP(_version) \
(_version >= _XPC_VERSION(1, 1))
+#define ZERO_STAMP ((struct timespec){0, 0})
/*
* compare stamps - the return value is:
*
@@ -218,10 +224,10 @@
*
* An array of these structures, one per partition, will be defined. As a
* partition becomes active XPC will copy the array entry corresponding to
- * itself from that partition. It is desirable that the size of this
- * structure evenly divide into a cacheline, such that none of the entries
- * in this array crosses a cacheline boundary. As it is now, each entry
- * occupies half a cacheline.
+ * itself from that partition. It is desirable that the size of this structure
+ * evenly divides into a 128-byte cacheline, such that none of the entries in
+ * this array crosses a 128-byte cacheline boundary. As it is now, each entry
+ * occupies a 64-byte cacheline.
*/
struct xpc_vars_part {
u64 magic;
@@ -632,16 +638,25 @@
extern void xpc_create_kthreads(struct xpc_channel *, int, int);
extern void xpc_disconnect_wait(int);
+extern enum xp_retval (*xpc_rsvd_page_init) (struct xpc_rsvd_page *);
+
+/* found in xpc_sn2.c */
+extern void xpc_init_sn2(void);
+extern struct xpc_vars *xpc_vars; /*>>> eliminate from here */
+extern struct xpc_vars_part *xpc_vars_part; /*>>> eliminate from here */
+
+/* found in xpc_uv.c */
+extern void xpc_init_uv(void);
+
/* found in xpc_partition.c */
extern int xpc_exiting;
-extern struct xpc_vars *xpc_vars;
+extern int xp_nasid_mask_words;
extern struct xpc_rsvd_page *xpc_rsvd_page;
-extern struct xpc_vars_part *xpc_vars_part;
extern struct xpc_partition *xpc_partitions;
extern char *xpc_remote_copy_buffer;
extern void *xpc_remote_copy_buffer_base;
extern void *xpc_kmalloc_cacheline_aligned(size_t, gfp_t, void **);
-extern struct xpc_rsvd_page *xpc_rsvd_page_init(void);
+extern struct xpc_rsvd_page *xpc_setup_rsvd_page(void);
extern void xpc_allow_IPI_ops(void);
extern void xpc_restrict_IPI_ops(void);
extern int xpc_identify_act_IRQ_sender(void);
diff --git a/drivers/misc/sgi-xp/xpc_main.c b/drivers/misc/sgi-xp/xpc_main.c
index a05c7c7..2180f1f 100644
--- a/drivers/misc/sgi-xp/xpc_main.c
+++ b/drivers/misc/sgi-xp/xpc_main.c
@@ -175,6 +175,8 @@
.notifier_call = xpc_system_die,
};
+enum xp_retval (*xpc_rsvd_page_init) (struct xpc_rsvd_page *rp);
+
/*
* Timer function to enforce the timelimit on the partition disengage request.
*/
@@ -949,7 +951,7 @@
DBUG_ON(xpc_partition_engaged(-1UL));
/* indicate to others that our reserved page is uninitialized */
- xpc_rsvd_page->vars_pa = 0;
+ xpc_rsvd_page->stamp = ZERO_STAMP;
/* now it's time to eliminate our heartbeat */
del_timer_sync(&xpc_hb_timer);
@@ -1128,8 +1130,24 @@
struct task_struct *kthread;
size_t buf_size;
- if (!ia64_platform_is("sn2"))
+ if (is_shub()) {
+ /*
+ * The ia64-sn2 architecture supports at most 64 partitions.
+ * And the inability to unregister remote AMOs restricts us
+ * further to only support exactly 64 partitions on this
+ * architecture, no less.
+ */
+ if (xp_max_npartitions != 64)
+ return -EINVAL;
+
+ xpc_init_sn2();
+
+ } else if (is_uv()) {
+ xpc_init_uv();
+
+ } else {
return -ENODEV;
+ }
snprintf(xpc_part->bus_id, BUS_ID_SIZE, "part");
snprintf(xpc_chan->bus_id, BUS_ID_SIZE, "chan");
@@ -1214,7 +1232,7 @@
* other partitions to discover we are alive and establish initial
* communications.
*/
- xpc_rsvd_page = xpc_rsvd_page_init();
+ xpc_rsvd_page = xpc_setup_rsvd_page();
if (xpc_rsvd_page == NULL) {
dev_err(xpc_part, "can't setup our reserved page\n");
ret = -EBUSY;
@@ -1273,7 +1291,8 @@
/* initialization was not successful */
out_4:
/* indicate to others that our reserved page is uninitialized */
- xpc_rsvd_page->vars_pa = 0;
+ xpc_rsvd_page->stamp = ZERO_STAMP;
+
del_timer_sync(&xpc_hb_timer);
(void)unregister_die_notifier(&xpc_die_notifier);
(void)unregister_reboot_notifier(&xpc_reboot_notifier);
diff --git a/drivers/misc/sgi-xp/xpc_partition.c b/drivers/misc/sgi-xp/xpc_partition.c
index 6c82f20..1db84cb 100644
--- a/drivers/misc/sgi-xp/xpc_partition.c
+++ b/drivers/misc/sgi-xp/xpc_partition.c
@@ -20,7 +20,6 @@
#include <linux/cache.h>
#include <linux/mmzone.h>
#include <linux/nodemask.h>
-#include <asm/uncached.h>
#include <asm/sn/intr.h>
#include <asm/sn/sn_sal.h>
#include <asm/sn/nodepda.h>
@@ -44,11 +43,10 @@
struct xpc_rsvd_page *xpc_rsvd_page;
static u64 *xpc_part_nasids;
static u64 *xpc_mach_nasids;
-struct xpc_vars *xpc_vars;
-struct xpc_vars_part *xpc_vars_part;
-static int xp_nasid_mask_bytes; /* actual size in bytes of nasid mask */
-static int xp_nasid_mask_words; /* actual size in words of nasid mask */
+/* >>> next two variables should be 'xpc_' if they remain here */
+static int xp_sizeof_nasid_mask; /* actual size in bytes of nasid mask */
+int xp_nasid_mask_words; /* actual size in words of nasid mask */
struct xpc_partition *xpc_partitions;
@@ -150,12 +148,10 @@
* communications.
*/
struct xpc_rsvd_page *
-xpc_rsvd_page_init(void)
+xpc_setup_rsvd_page(void)
{
struct xpc_rsvd_page *rp;
- AMO_t *amos_page;
- u64 rp_pa, nasid_array = 0;
- int i, ret;
+ u64 rp_pa;
/* get the local reserved page's address */
@@ -168,110 +164,44 @@
}
rp = (struct xpc_rsvd_page *)__va(rp_pa);
- if (rp->partid != sn_partition_id) {
- dev_err(xpc_part, "the reserved page's partid of %d should be "
- "%d\n", rp->partid, sn_partition_id);
+ if (rp->SAL_version < 3) {
+ /* SAL_versions < 3 had a SAL_partid defined as a u8 */
+ rp->SAL_partid &= 0xff;
+ }
+ BUG_ON(rp->SAL_partid != sn_partition_id);
+
+ if (rp->SAL_partid < 0 || rp->SAL_partid >= xp_max_npartitions) {
+ dev_err(xpc_part, "the reserved page's partid of %d is outside "
+ "supported range (< 0 || >= %d)\n", rp->SAL_partid,
+ xp_max_npartitions);
return NULL;
}
rp->version = XPC_RP_VERSION;
+ rp->max_npartitions = xp_max_npartitions;
/* establish the actual sizes of the nasid masks */
if (rp->SAL_version == 1) {
/* SAL_version 1 didn't set the nasids_size field */
- rp->nasids_size = 128;
+ rp->SAL_nasids_size = 128;
}
- xp_nasid_mask_bytes = rp->nasids_size;
- xp_nasid_mask_words = xp_nasid_mask_bytes / 8;
+ xp_sizeof_nasid_mask = rp->SAL_nasids_size;
+ xp_nasid_mask_words = DIV_ROUND_UP(xp_sizeof_nasid_mask,
+ BYTES_PER_WORD);
/* setup the pointers to the various items in the reserved page */
xpc_part_nasids = XPC_RP_PART_NASIDS(rp);
xpc_mach_nasids = XPC_RP_MACH_NASIDS(rp);
- xpc_vars = XPC_RP_VARS(rp);
- xpc_vars_part = XPC_RP_VARS_PART(rp);
+
+ if (xpc_rsvd_page_init(rp) != xpSuccess)
+ return NULL;
/*
- * Before clearing xpc_vars, see if a page of AMOs had been previously
- * allocated. If not we'll need to allocate one and set permissions
- * so that cross-partition AMOs are allowed.
- *
- * The allocated AMO page needs MCA reporting to remain disabled after
- * XPC has unloaded. To make this work, we keep a copy of the pointer
- * to this page (i.e., amos_page) in the struct xpc_vars structure,
- * which is pointed to by the reserved page, and re-use that saved copy
- * on subsequent loads of XPC. This AMO page is never freed, and its
- * memory protections are never restricted.
- */
- amos_page = xpc_vars->amos_page;
- if (amos_page == NULL) {
- amos_page = (AMO_t *)TO_AMO(uncached_alloc_page(0, 1));
- if (amos_page == NULL) {
- dev_err(xpc_part, "can't allocate page of AMOs\n");
- return NULL;
- }
-
- /*
- * Open up AMO-R/W to cpu. This is done for Shub 1.1 systems
- * when xpc_allow_IPI_ops() is called via xpc_hb_init().
- */
- if (!enable_shub_wars_1_1()) {
- ret = sn_change_memprotect(ia64_tpa((u64)amos_page),
- PAGE_SIZE,
- SN_MEMPROT_ACCESS_CLASS_1,
- &nasid_array);
- if (ret != 0) {
- dev_err(xpc_part, "can't change memory "
- "protections\n");
- uncached_free_page(__IA64_UNCACHED_OFFSET |
- TO_PHYS((u64)amos_page), 1);
- return NULL;
- }
- }
- } else if (!IS_AMO_ADDRESS((u64)amos_page)) {
- /*
- * EFI's XPBOOT can also set amos_page in the reserved page,
- * but it happens to leave it as an uncached physical address
- * and we need it to be an uncached virtual, so we'll have to
- * convert it.
- */
- if (!IS_AMO_PHYS_ADDRESS((u64)amos_page)) {
- dev_err(xpc_part, "previously used amos_page address "
- "is bad = 0x%p\n", (void *)amos_page);
- return NULL;
- }
- amos_page = (AMO_t *)TO_AMO((u64)amos_page);
- }
-
- /* clear xpc_vars */
- memset(xpc_vars, 0, sizeof(struct xpc_vars));
-
- xpc_vars->version = XPC_V_VERSION;
- xpc_vars->act_nasid = cpuid_to_nasid(0);
- xpc_vars->act_phys_cpuid = cpu_physical_id(0);
- xpc_vars->vars_part_pa = __pa(xpc_vars_part);
- xpc_vars->amos_page_pa = ia64_tpa((u64)amos_page);
- xpc_vars->amos_page = amos_page; /* save for next load of XPC */
-
- /* clear xpc_vars_part */
- memset((u64 *)xpc_vars_part, 0, sizeof(struct xpc_vars_part) *
- xp_max_npartitions);
-
- /* initialize the activate IRQ related AMO variables */
- for (i = 0; i < xp_nasid_mask_words; i++)
- (void)xpc_IPI_init(XPC_ACTIVATE_IRQ_AMOS + i);
-
- /* initialize the engaged remote partitions related AMO variables */
- (void)xpc_IPI_init(XPC_ENGAGED_PARTITIONS_AMO);
- (void)xpc_IPI_init(XPC_DISENGAGE_REQUEST_AMO);
-
- /* timestamp of when reserved page was setup by XPC */
- rp->stamp = CURRENT_TIME;
-
- /*
+ * Set timestamp of when reserved page was setup by XPC.
* This signifies to the remote partition that our reserved
* page is initialized.
*/
- rp->vars_pa = __pa(xpc_vars);
+ rp->stamp = CURRENT_TIME;
return rp;
}
@@ -465,7 +395,7 @@
/* pull over the reserved page header and part_nasids mask */
ret = xp_remote_memcpy(remote_rp, (void *)*remote_rp_pa,
- XPC_RP_HEADER_SIZE + xp_nasid_mask_bytes);
+ XPC_RP_HEADER_SIZE + xp_sizeof_nasid_mask);
if (ret != xpSuccess)
return ret;
@@ -476,19 +406,28 @@
discovered_nasids[i] |= remote_part_nasids[i];
}
- /* check that the partid is for another partition */
+ /* check that the partid is valid and is for another partition */
- if (remote_rp->partid < 0 || remote_rp->partid >= xp_max_npartitions)
+ if (remote_rp->SAL_partid < 0 ||
+ remote_rp->SAL_partid >= xp_max_npartitions) {
return xpInvalidPartid;
+ }
- if (remote_rp->partid == sn_partition_id)
+ if (remote_rp->SAL_partid == sn_partition_id)
return xpLocalPartid;
+ /* see if the rest of the reserved page has been set up by XPC */
+ if (timespec_equal(&remote_rp->stamp, &ZERO_STAMP))
+ return xpRsvdPageNotSet;
+
if (XPC_VERSION_MAJOR(remote_rp->version) !=
XPC_VERSION_MAJOR(XPC_RP_VERSION)) {
return xpBadVersion;
}
+ if (remote_rp->max_npartitions <= sn_partition_id)
+ return xpInvalidPartid;
+
return xpSuccess;
}
@@ -592,7 +531,7 @@
int remote_rp_version;
int reactivate = 0;
int stamp_diff;
- struct timespec remote_rp_stamp = { 0, 0 };
+ struct timespec remote_rp_stamp = { 0, 0 }; /*>>> ZERO_STAMP */
short partid;
struct xpc_partition *part;
enum xp_retval ret;
@@ -608,12 +547,12 @@
return;
}
- remote_vars_pa = remote_rp->vars_pa;
+ remote_vars_pa = remote_rp->sn.vars_pa;
remote_rp_version = remote_rp->version;
if (XPC_SUPPORTS_RP_STAMP(remote_rp_version))
remote_rp_stamp = remote_rp->stamp;
- partid = remote_rp->partid;
+ partid = remote_rp->SAL_partid;
part = &xpc_partitions[partid];
/* pull over the cross partition variables */
@@ -977,7 +916,7 @@
enum xp_retval ret;
remote_rp = xpc_kmalloc_cacheline_aligned(XPC_RP_HEADER_SIZE +
- xp_nasid_mask_bytes,
+ xp_sizeof_nasid_mask,
GFP_KERNEL, &remote_rp_base);
if (remote_rp == NULL)
return;
@@ -1063,9 +1002,9 @@
continue;
}
- remote_vars_pa = remote_rp->vars_pa;
+ remote_vars_pa = remote_rp->sn.vars_pa;
- partid = remote_rp->partid;
+ partid = remote_rp->SAL_partid;
part = &xpc_partitions[partid];
/* pull over the cross partition variables */
@@ -1155,5 +1094,5 @@
part_nasid_pa = (u64)XPC_RP_PART_NASIDS(part->remote_rp_pa);
return xp_remote_memcpy(nasid_mask, (void *)part_nasid_pa,
- xp_nasid_mask_bytes);
+ xp_sizeof_nasid_mask);
}
diff --git a/drivers/misc/sgi-xp/xpc_sn2.c b/drivers/misc/sgi-xp/xpc_sn2.c
new file mode 100644
index 0000000..5a37348
--- /dev/null
+++ b/drivers/misc/sgi-xp/xpc_sn2.c
@@ -0,0 +1,111 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved.
+ */
+
+/*
+ * Cross Partition Communication (XPC) sn2-based functions.
+ *
+ * Architecture specific implementation of common functions.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <asm/uncached.h>
+#include <asm/sn/sn_sal.h>
+#include "xpc.h"
+
+struct xpc_vars *xpc_vars;
+struct xpc_vars_part *xpc_vars_part;
+
+static enum xp_retval
+xpc_rsvd_page_init_sn2(struct xpc_rsvd_page *rp)
+{
+ AMO_t *amos_page;
+ u64 nasid_array = 0;
+ int i;
+ int ret;
+
+ xpc_vars = XPC_RP_VARS(rp);
+
+ rp->sn.vars_pa = __pa(xpc_vars);
+
+ xpc_vars_part = XPC_RP_VARS_PART(rp);
+
+ /*
+ * Before clearing xpc_vars, see if a page of AMOs had been previously
+ * allocated. If not we'll need to allocate one and set permissions
+ * so that cross-partition AMOs are allowed.
+ *
+ * The allocated AMO page needs MCA reporting to remain disabled after
+ * XPC has unloaded. To make this work, we keep a copy of the pointer
+ * to this page (i.e., amos_page) in the struct xpc_vars structure,
+ * which is pointed to by the reserved page, and re-use that saved copy
+ * on subsequent loads of XPC. This AMO page is never freed, and its
+ * memory protections are never restricted.
+ */
+ amos_page = xpc_vars->amos_page;
+ if (amos_page == NULL) {
+ amos_page = (AMO_t *)TO_AMO(uncached_alloc_page(0, 1));
+ if (amos_page == NULL) {
+ dev_err(xpc_part, "can't allocate page of AMOs\n");
+ return xpNoMemory;
+ }
+
+ /*
+ * Open up AMO-R/W to cpu. This is done for Shub 1.1 systems
+ * when xpc_allow_IPI_ops() is called via xpc_hb_init().
+ */
+ if (!enable_shub_wars_1_1()) {
+ ret = sn_change_memprotect(ia64_tpa((u64)amos_page),
+ PAGE_SIZE,
+ SN_MEMPROT_ACCESS_CLASS_1,
+ &nasid_array);
+ if (ret != 0) {
+ dev_err(xpc_part, "can't change memory "
+ "protections\n");
+ uncached_free_page(__IA64_UNCACHED_OFFSET |
+ TO_PHYS((u64)amos_page), 1);
+ return xpSalError;
+ }
+ }
+ }
+
+ /* clear xpc_vars */
+ memset(xpc_vars, 0, sizeof(struct xpc_vars));
+
+ xpc_vars->version = XPC_V_VERSION;
+ xpc_vars->act_nasid = cpuid_to_nasid(0);
+ xpc_vars->act_phys_cpuid = cpu_physical_id(0);
+ xpc_vars->vars_part_pa = __pa(xpc_vars_part);
+ xpc_vars->amos_page_pa = ia64_tpa((u64)amos_page);
+ xpc_vars->amos_page = amos_page; /* save for next load of XPC */
+
+ /* clear xpc_vars_part */
+ memset((u64 *)xpc_vars_part, 0, sizeof(struct xpc_vars_part) *
+ xp_max_npartitions);
+
+ /* initialize the activate IRQ related AMO variables */
+ for (i = 0; i < xp_nasid_mask_words; i++)
+ (void)xpc_IPI_init(XPC_ACTIVATE_IRQ_AMOS + i);
+
+ /* initialize the engaged remote partitions related AMO variables */
+ (void)xpc_IPI_init(XPC_ENGAGED_PARTITIONS_AMO);
+ (void)xpc_IPI_init(XPC_DISENGAGE_REQUEST_AMO);
+
+ return xpSuccess;
+}
+
+void
+xpc_init_sn2(void)
+{
+ xpc_rsvd_page_init = xpc_rsvd_page_init_sn2;
+}
+
+void
+xpc_exit_sn2(void)
+{
+}
diff --git a/drivers/misc/sgi-xp/xpc_uv.c b/drivers/misc/sgi-xp/xpc_uv.c
new file mode 100644
index 0000000..8327cd4
--- /dev/null
+++ b/drivers/misc/sgi-xp/xpc_uv.c
@@ -0,0 +1,48 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved.
+ */
+
+/*
+ * Cross Partition Communication (XPC) uv-based functions.
+ *
+ * Architecture specific implementation of common functions.
+ *
+ */
+
+#include <linux/kernel.h>
+
+/* >>> #include <gru/grukservices.h> */
+/* >>> uv_gpa() is defined in <gru/grukservices.h> */
+#define uv_gpa(_a) ((unsigned long)_a)
+
+/* >>> temporarily define next three items for xpc.h */
+#define SGI_XPC_ACTIVATE 23
+#define SGI_XPC_NOTIFY 24
+#define sn_send_IPI_phys(_a, _b, _c, _d)
+
+#include "xpc.h"
+
+static void *xpc_activate_mq;
+
+static enum xp_retval
+xpc_rsvd_page_init_uv(struct xpc_rsvd_page *rp)
+{
+ /* >>> need to have established xpc_activate_mq earlier */
+ rp->sn.activate_mq_gpa = uv_gpa(xpc_activate_mq);
+ return xpSuccess;
+}
+
+void
+xpc_init_uv(void)
+{
+ xpc_rsvd_page_init = xpc_rsvd_page_init_uv;
+}
+
+void
+xpc_exit_uv(void)
+{
+}
