aboutsummaryrefslogtreecommitdiff
path: root/drivers/misc/sgi-xp/xpc.h
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/misc/sgi-xp/xpc.h')
-rw-r--r--drivers/misc/sgi-xp/xpc.h1267
1 files changed, 1267 insertions, 0 deletions
diff --git a/drivers/misc/sgi-xp/xpc.h b/drivers/misc/sgi-xp/xpc.h
new file mode 100644
index 00000000000..14e70ee53eb
--- /dev/null
+++ b/drivers/misc/sgi-xp/xpc.h
@@ -0,0 +1,1267 @@
+/*
+ * 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) 2004-2008 Silicon Graphics, Inc. All Rights Reserved.
+ */
+
+
+/*
+ * Cross Partition Communication (XPC) structures and macros.
+ */
+
+#ifndef _DRIVERS_MISC_SGIXP_XPC_H
+#define _DRIVERS_MISC_SGIXP_XPC_H
+
+
+#include <linux/interrupt.h>
+#include <linux/sysctl.h>
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/completion.h>
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/sn/bte.h>
+#include <asm/sn/clksupport.h>
+#include <asm/sn/addrs.h>
+#include <asm/sn/mspec.h>
+#include <asm/sn/shub_mmr.h>
+#include "xp.h"
+
+
+/*
+ * XPC Version numbers consist of a major and minor number. XPC can always
+ * talk to versions with same major #, and never talk to versions with a
+ * different major #.
+ */
+#define _XPC_VERSION(_maj, _min) (((_maj) << 4) | ((_min) & 0xf))
+#define XPC_VERSION_MAJOR(_v) ((_v) >> 4)
+#define XPC_VERSION_MINOR(_v) ((_v) & 0xf)
+
+
+/*
+ * The next macros define word or bit representations for given
+ * C-brick nasid in either the SAL provided bit array representing
+ * nasids in the partition/machine or the AMO_t array used for
+ * inter-partition initiation communications.
+ *
+ * For SN2 machines, C-Bricks are alway even numbered NASIDs. As
+ * such, some space will be saved by insisting that nasid information
+ * passed from SAL always be packed for C-Bricks and the
+ * cross-partition interrupts use the same packing scheme.
+ */
+#define XPC_NASID_W_INDEX(_n) (((_n) / 64) / 2)
+#define XPC_NASID_B_INDEX(_n) (((_n) / 2) & (64 - 1))
+#define XPC_NASID_IN_ARRAY(_n, _p) ((_p)[XPC_NASID_W_INDEX(_n)] & \
+ (1UL << XPC_NASID_B_INDEX(_n)))
+#define XPC_NASID_FROM_W_B(_w, _b) (((_w) * 64 + (_b)) * 2)
+
+#define XPC_HB_DEFAULT_INTERVAL 5 /* incr HB every x secs */
+#define XPC_HB_CHECK_DEFAULT_INTERVAL 20 /* check HB every x secs */
+
+/* define the process name of HB checker and the CPU it is pinned to */
+#define XPC_HB_CHECK_THREAD_NAME "xpc_hb"
+#define XPC_HB_CHECK_CPU 0
+
+/* define the process name of the discovery thread */
+#define XPC_DISCOVERY_THREAD_NAME "xpc_discovery"
+
+
+/*
+ * the reserved page
+ *
+ * SAL reserves one page of memory per partition for XPC. Though a full page
+ * in length (16384 bytes), its starting address is not page aligned, but it
+ * is cacheline aligned. The reserved page consists of the following:
+ *
+ * reserved page header
+ *
+ * The first cacheline of the reserved page contains 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
+ * partition's reserved page.)
+ *
+ * part_nasids mask
+ * mach_nasids mask
+ *
+ * SAL also sets up two bitmaps (or masks), one that reflects the actual
+ * nasids in this partition (part_nasids), and the other that reflects
+ * the actual nasids in the entire machine (mach_nasids). We're only
+ * interested in the even numbered nasids (which contain the processors
+ * and/or memory), so we only need half as many bits to represent the
+ * 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
+ * mask pointers are xpc_part_nasids and xpc_mach_nasids.)
+ *
+ * vars
+ * vars part
+ *
+ * Immediately following the mach_nasids mask are the XPC variables
+ * required by other partitions. First are those that are generic to all
+ * partitions (vars), followed on the next available cacheline by those
+ * 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.
+ */
+struct xpc_rsvd_page {
+ u64 SAL_signature; /* SAL: unique signature */
+ u64 SAL_version; /* SAL: version */
+ u8 partid; /* SAL: partition ID */
+ u8 version;
+ u8 pad1[6]; /* align to next u64 in cacheline */
+ volatile u64 vars_pa;
+ 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 */
+};
+
+#define XPC_RP_VERSION _XPC_VERSION(1,1) /* version 1.1 of the reserved page */
+
+#define XPC_SUPPORTS_RP_STAMP(_version) \
+ (_version >= _XPC_VERSION(1,1))
+
+/*
+ * compare stamps - the return value is:
+ *
+ * < 0, if stamp1 < stamp2
+ * = 0, if stamp1 == stamp2
+ * > 0, if stamp1 > stamp2
+ */
+static inline int
+xpc_compare_stamps(struct timespec *stamp1, struct timespec *stamp2)
+{
+ int ret;
+
+
+ if ((ret = stamp1->tv_sec - stamp2->tv_sec) == 0) {
+ ret = stamp1->tv_nsec - stamp2->tv_nsec;
+ }
+ return ret;
+}
+
+
+/*
+ * Define the structures by which XPC variables can be exported to other
+ * partitions. (There are two: struct xpc_vars and struct xpc_vars_part)
+ */
+
+/*
+ * The following structure describes the partition generic variables
+ * needed by other partitions in order to properly initialize.
+ *
+ * struct xpc_vars version number also applies to struct xpc_vars_part.
+ * Changes to either structure and/or related functionality should be
+ * reflected by incrementing either the major or minor version numbers
+ * of struct xpc_vars.
+ */
+struct xpc_vars {
+ u8 version;
+ u64 heartbeat;
+ u64 heartbeating_to_mask;
+ u64 heartbeat_offline; /* if 0, heartbeat should be changing */
+ int act_nasid;
+ int act_phys_cpuid;
+ u64 vars_part_pa;
+ u64 amos_page_pa; /* paddr of page of AMOs from MSPEC driver */
+ AMO_t *amos_page; /* vaddr of page of AMOs from MSPEC driver */
+};
+
+#define XPC_V_VERSION _XPC_VERSION(3,1) /* version 3.1 of the cross vars */
+
+#define XPC_SUPPORTS_DISENGAGE_REQUEST(_version) \
+ (_version >= _XPC_VERSION(3,1))
+
+
+static inline int
+xpc_hb_allowed(partid_t partid, struct xpc_vars *vars)
+{
+ return ((vars->heartbeating_to_mask & (1UL << partid)) != 0);
+}
+
+static inline void
+xpc_allow_hb(partid_t partid, struct xpc_vars *vars)
+{
+ u64 old_mask, new_mask;
+
+ do {
+ old_mask = vars->heartbeating_to_mask;
+ new_mask = (old_mask | (1UL << partid));
+ } while (cmpxchg(&vars->heartbeating_to_mask, old_mask, new_mask) !=
+ old_mask);
+}
+
+static inline void
+xpc_disallow_hb(partid_t partid, struct xpc_vars *vars)
+{
+ u64 old_mask, new_mask;
+
+ do {
+ old_mask = vars->heartbeating_to_mask;
+ new_mask = (old_mask & ~(1UL << partid));
+ } while (cmpxchg(&vars->heartbeating_to_mask, old_mask, new_mask) !=
+ old_mask);
+}
+
+
+/*
+ * The AMOs page consists of a number of AMO variables which are divided into
+ * four groups, The first two groups are used to identify an IRQ's sender.
+ * These two groups consist of 64 and 128 AMO variables respectively. The last
+ * two groups, consisting of just one AMO variable each, are used to identify
+ * the remote partitions that are currently engaged (from the viewpoint of
+ * the XPC running on the remote partition).
+ */
+#define XPC_NOTIFY_IRQ_AMOS 0
+#define XPC_ACTIVATE_IRQ_AMOS (XPC_NOTIFY_IRQ_AMOS + XP_MAX_PARTITIONS)
+#define XPC_ENGAGED_PARTITIONS_AMO (XPC_ACTIVATE_IRQ_AMOS + XP_NASID_MASK_WORDS)
+#define XPC_DISENGAGE_REQUEST_AMO (XPC_ENGAGED_PARTITIONS_AMO + 1)
+
+
+/*
+ * The following structure describes the per partition specific variables.
+ *
+ * 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.
+ */
+struct xpc_vars_part {
+ volatile u64 magic;
+
+ u64 openclose_args_pa; /* physical address of open and close args */
+ u64 GPs_pa; /* physical address of Get/Put values */
+
+ u64 IPI_amo_pa; /* physical address of IPI AMO_t structure */
+ int IPI_nasid; /* nasid of where to send IPIs */
+ int IPI_phys_cpuid; /* physical CPU ID of where to send IPIs */
+
+ u8 nchannels; /* #of defined channels supported */
+
+ u8 reserved[23]; /* pad to a full 64 bytes */
+};
+
+/*
+ * The vars_part MAGIC numbers play a part in the first contact protocol.
+ *
+ * MAGIC1 indicates that the per partition specific variables for a remote
+ * partition have been initialized by this partition.
+ *
+ * MAGIC2 indicates that this partition has pulled the remote partititions
+ * per partition variables that pertain to this partition.
+ */
+#define XPC_VP_MAGIC1 0x0053524156435058L /* 'XPCVARS\0'L (little endian) */
+#define XPC_VP_MAGIC2 0x0073726176435058L /* 'XPCvars\0'L (little endian) */
+
+
+/* the reserved page sizes and offsets */
+
+#define XPC_RP_HEADER_SIZE L1_CACHE_ALIGN(sizeof(struct xpc_rsvd_page))
+#define XPC_RP_VARS_SIZE L1_CACHE_ALIGN(sizeof(struct xpc_vars))
+
+#define XPC_RP_PART_NASIDS(_rp) (u64 *) ((u8 *) _rp + XPC_RP_HEADER_SIZE)
+#define XPC_RP_MACH_NASIDS(_rp) (XPC_RP_PART_NASIDS(_rp) + xp_nasid_mask_words)
+#define XPC_RP_VARS(_rp) ((struct xpc_vars *) XPC_RP_MACH_NASIDS(_rp) + xp_nasid_mask_words)
+#define XPC_RP_VARS_PART(_rp) (struct xpc_vars_part *) ((u8 *) XPC_RP_VARS(rp) + XPC_RP_VARS_SIZE)
+
+
+/*
+ * Functions registered by add_timer() or called by kernel_thread() only
+ * allow for a single 64-bit argument. The following macros can be used to
+ * pack and unpack two (32-bit, 16-bit or 8-bit) arguments into or out from
+ * the passed argument.
+ */
+#define XPC_PACK_ARGS(_arg1, _arg2) \
+ ((((u64) _arg1) & 0xffffffff) | \
+ ((((u64) _arg2) & 0xffffffff) << 32))
+
+#define XPC_UNPACK_ARG1(_args) (((u64) _args) & 0xffffffff)
+#define XPC_UNPACK_ARG2(_args) ((((u64) _args) >> 32) & 0xffffffff)
+
+
+
+/*
+ * Define a Get/Put value pair (pointers) used with a message queue.
+ */
+struct xpc_gp {
+ volatile s64 get; /* Get value */
+ volatile s64 put; /* Put value */
+};
+
+#define XPC_GP_SIZE \
+ L1_CACHE_ALIGN(sizeof(struct xpc_gp) * XPC_NCHANNELS)
+
+
+
+/*
+ * Define a structure that contains arguments associated with opening and
+ * closing a channel.
+ */
+struct xpc_openclose_args {
+ u16 reason; /* reason why channel is closing */
+ u16 msg_size; /* sizeof each message entry */
+ u16 remote_nentries; /* #of message entries in remote msg queue */
+ u16 local_nentries; /* #of message entries in local msg queue */
+ u64 local_msgqueue_pa; /* physical address of local message queue */
+};
+
+#define XPC_OPENCLOSE_ARGS_SIZE \
+ L1_CACHE_ALIGN(sizeof(struct xpc_openclose_args) * XPC_NCHANNELS)
+
+
+
+/* struct xpc_msg flags */
+
+#define XPC_M_DONE 0x01 /* msg has been received/consumed */
+#define XPC_M_READY 0x02 /* msg is ready to be sent */
+#define XPC_M_INTERRUPT 0x04 /* send interrupt when msg consumed */
+
+
+#define XPC_MSG_ADDRESS(_payload) \
+ ((struct xpc_msg *)((u8 *)(_payload) - XPC_MSG_PAYLOAD_OFFSET))
+
+
+
+/*
+ * Defines notify entry.
+ *
+ * This is used to notify a message's sender that their message was received
+ * and consumed by the intended recipient.
+ */
+struct xpc_notify {
+ volatile u8 type; /* type of notification */
+
+ /* the following two fields are only used if type == XPC_N_CALL */
+ xpc_notify_func func; /* user's notify function */
+ void *key; /* pointer to user's key */
+};
+
+/* struct xpc_notify type of notification */
+
+#define XPC_N_CALL 0x01 /* notify function provided by user */
+
+
+
+/*
+ * Define the structure that manages all the stuff required by a channel. In
+ * particular, they are used to manage the messages sent across the channel.
+ *
+ * This structure is private to a partition, and is NOT shared across the
+ * partition boundary.
+ *
+ * There is an array of these structures for each remote partition. It is
+ * allocated at the time a partition becomes active. The array contains one
+ * of these structures for each potential channel connection to that partition.
+ *
+ * Each of these structures manages two message queues (circular buffers).
+ * They are allocated at the time a channel connection is made. One of
+ * these message queues (local_msgqueue) holds the locally created messages
+ * that are destined for the remote partition. The other of these message
+ * queues (remote_msgqueue) is a locally cached copy of the remote partition's
+ * own local_msgqueue.
+ *
+ * The following is a description of the Get/Put pointers used to manage these
+ * two message queues. Consider the local_msgqueue to be on one partition
+ * and the remote_msgqueue to be its cached copy on another partition. A
+ * description of what each of the lettered areas contains is included.
+ *
+ *
+ * local_msgqueue remote_msgqueue
+ *
+ * |/////////| |/////////|
+ * w_remote_GP.get --> +---------+ |/////////|
+ * | F | |/////////|
+ * remote_GP.get --> +---------+ +---------+ <-- local_GP->get
+ * | | | |
+ * | | | E |
+ * | | | |
+ * | | +---------+ <-- w_local_GP.get
+ * | B | |/////////|
+ * | | |////D////|
+ * | | |/////////|
+ * | | +---------+ <-- w_remote_GP.put
+ * | | |////C////|
+ * local_GP->put --> +---------+ +---------+ <-- remote_GP.put
+ * | | |/////////|
+ * | A | |/////////|
+ * | | |/////////|
+ * w_local_GP.put --> +---------+ |/////////|
+ * |/////////| |/////////|
+ *
+ *
+ * ( remote_GP.[get|put] are cached copies of the remote
+ * partition's local_GP->[get|put], and thus their values can
+ * lag behind their counterparts on the remote partition. )
+ *
+ *
+ * A - Messages that have been allocated, but have not yet been sent to the
+ * remote partition.
+ *
+ * B - Messages that have been sent, but have not yet been acknowledged by the
+ * remote partition as having been received.
+ *
+ * C - Area that needs to be prepared for the copying of sent messages, by
+ * the clearing of the message flags of any previously received messages.
+ *
+ * D - Area into which sent messages are to be copied from the remote
+ * partition's local_msgqueue and then delivered to their intended
+ * recipients. [ To allow for a multi-message copy, another pointer
+ * (next_msg_to_pull) has been added to keep track of the next message
+ * number needing to be copied (pulled). It chases after w_remote_GP.put.
+ * Any messages lying between w_local_GP.get and next_msg_to_pull have
+ * been copied and are ready to be delivered. ]
+ *
+ * E - Messages that have been copied and delivered, but have not yet been
+ * acknowledged by the recipient as having been received.
+ *
+ * F - Messages that have been acknowledged, but XPC has not yet notified the
+ * sender that the message was received by its intended recipient.
+ * This is also an area that needs to be prepared for the allocating of
+ * new messages, by the clearing of the message flags of the acknowledged
+ * messages.
+ */
+struct xpc_channel {
+ partid_t partid; /* ID of remote partition connected */
+ spinlock_t lock; /* lock for updating this structure */
+ u32 flags; /* general flags */
+
+ enum xpc_retval reason; /* reason why channel is disconnect'g */
+ int reason_line; /* line# disconnect initiated from */
+
+ u16 number; /* channel # */
+
+ u16 msg_size; /* sizeof each msg entry */
+ u16 local_nentries; /* #of msg entries in local msg queue */
+ u16 remote_nentries; /* #of msg entries in remote msg queue*/
+
+ void *local_msgqueue_base; /* base address of kmalloc'd space */
+ struct xpc_msg *local_msgqueue; /* local message queue */
+ void *remote_msgqueue_base; /* base address of kmalloc'd space */
+ struct xpc_msg *remote_msgqueue;/* cached copy of remote partition's */
+ /* local message queue */
+ u64 remote_msgqueue_pa; /* phys addr of remote partition's */
+ /* local message queue */
+
+ atomic_t references; /* #of external references to queues */
+
+ atomic_t n_on_msg_allocate_wq; /* #on msg allocation wait queue */
+ wait_queue_head_t msg_allocate_wq; /* msg allocation wait queue */
+
+ u8 delayed_IPI_flags; /* IPI flags received, but delayed */
+ /* action until channel disconnected */
+
+ /* queue of msg senders who want to be notified when msg received */
+
+ atomic_t n_to_notify; /* #of msg senders to notify */
+ struct xpc_notify *notify_queue;/* notify queue for messages sent */
+
+ xpc_channel_func func; /* user's channel function */
+ void *key; /* pointer to user's key */
+
+ struct mutex msg_to_pull_mutex; /* next msg to pull serialization */
+ struct completion wdisconnect_wait; /* wait for channel disconnect */
+
+ struct xpc_openclose_args *local_openclose_args; /* args passed on */
+ /* opening or closing of channel */
+
+ /* various flavors of local and remote Get/Put values */
+
+ struct xpc_gp *local_GP; /* local Get/Put values */
+ struct xpc_gp remote_GP; /* remote Get/Put values */
+ struct xpc_gp w_local_GP; /* working local Get/Put values */
+ struct xpc_gp w_remote_GP; /* working remote Get/Put values */
+ s64 next_msg_to_pull; /* Put value of next msg to pull */
+
+ /* kthread management related fields */
+
+// >>> rethink having kthreads_assigned_limit and kthreads_idle_limit; perhaps
+// >>> allow the assigned limit be unbounded and let the idle limit be dynamic
+// >>> dependent on activity over the last interval of time
+ atomic_t kthreads_assigned; /* #of kthreads assigned to channel */
+ u32 kthreads_assigned_limit; /* limit on #of kthreads assigned */
+ atomic_t kthreads_idle; /* #of kthreads idle waiting for work */
+ u32 kthreads_idle_limit; /* limit on #of kthreads idle */
+ atomic_t kthreads_active; /* #of kthreads actively working */
+ // >>> following field is temporary
+ u32 kthreads_created; /* total #of kthreads created */
+
+ wait_queue_head_t idle_wq; /* idle kthread wait queue */
+
+} ____cacheline_aligned;
+
+
+/* struct xpc_channel flags */
+
+#define XPC_C_WASCONNECTED 0x00000001 /* channel was connected */
+
+#define XPC_C_ROPENREPLY 0x00000002 /* remote open channel reply */
+#define XPC_C_OPENREPLY 0x00000004 /* local open channel reply */
+#define XPC_C_ROPENREQUEST 0x00000008 /* remote open channel request */
+#define XPC_C_OPENREQUEST 0x00000010 /* local open channel request */
+
+#define XPC_C_SETUP 0x00000020 /* channel's msgqueues are alloc'd */
+#define XPC_C_CONNECTEDCALLOUT 0x00000040 /* connected callout initiated */
+#define XPC_C_CONNECTEDCALLOUT_MADE \
+ 0x00000080 /* connected callout completed */
+#define XPC_C_CONNECTED 0x00000100 /* local channel is connected */
+#define XPC_C_CONNECTING 0x00000200 /* channel is being connected */
+
+#define XPC_C_RCLOSEREPLY 0x00000400 /* remote close channel reply */
+#define XPC_C_CLOSEREPLY 0x00000800 /* local close channel reply */
+#define XPC_C_RCLOSEREQUEST 0x00001000 /* remote close channel request */
+#define XPC_C_CLOSEREQUEST 0x00002000 /* local close channel request */
+
+#define XPC_C_DISCONNECTED 0x00004000 /* channel is disconnected */
+#define XPC_C_DISCONNECTING 0x00008000 /* channel is being disconnected */
+#define XPC_C_DISCONNECTINGCALLOUT \
+ 0x00010000 /* disconnecting callout initiated */
+#define XPC_C_DISCONNECTINGCALLOUT_MADE \
+ 0x00020000 /* disconnecting callout completed */
+#define XPC_C_WDISCONNECT 0x00040000 /* waiting for channel disconnect */
+
+
+
+/*
+ * Manages channels on a partition basis. There is one of these structures
+ * for each partition (a partition will never utilize the structure that
+ * represents itself).
+ */
+struct xpc_partition {
+
+ /* XPC HB infrastructure */
+
+ u8 remote_rp_version; /* version# of partition's rsvd pg */
+ struct timespec remote_rp_stamp;/* time when rsvd pg was initialized */
+ u64 remote_rp_pa; /* phys addr of partition's rsvd pg */
+ u64 remote_vars_pa; /* phys addr of partition's vars */
+ u64 remote_vars_part_pa; /* phys addr of partition's vars part */
+ u64 last_heartbeat; /* HB at last read */
+ u64 remote_amos_page_pa; /* phys addr of partition's amos page */
+ int remote_act_nasid; /* active part's act/deact nasid */
+ int remote_act_phys_cpuid; /* active part's act/deact phys cpuid */
+ u32 act_IRQ_rcvd; /* IRQs since activation */
+ spinlock_t act_lock; /* protect updating of act_state */
+ u8 act_state; /* from XPC HB viewpoint */
+ u8 remote_vars_version; /* version# of partition's vars */
+ enum xpc_retval reason; /* reason partition is deactivating */
+ int reason_line; /* line# deactivation initiated from */
+ int reactivate_nasid; /* nasid in partition to reactivate */
+
+ unsigned long disengage_request_timeout; /* timeout in jiffies */
+ struct timer_list disengage_request_timer;
+
+
+ /* XPC infrastructure referencing and teardown control */
+
+ volatile u8 setup_state; /* infrastructure setup state */
+ wait_queue_head_t teardown_wq; /* kthread waiting to teardown infra */
+ atomic_t references; /* #of references to infrastructure */
+
+
+ /*
+ * NONE OF THE PRECEDING FIELDS OF THIS STRUCTURE WILL BE CLEARED WHEN
+ * XPC SETS UP THE NECESSARY INFRASTRUCTURE TO SUPPORT CROSS PARTITION
+ * COMMUNICATION. ALL OF THE FOLLOWING FIELDS WILL BE CLEARED. (THE
+ * 'nchannels' FIELD MUST BE THE FIRST OF THE FIELDS TO BE CLEARED.)
+ */
+
+
+ u8 nchannels; /* #of defined channels supported */
+ atomic_t nchannels_active; /* #of channels that are not DISCONNECTED */
+ atomic_t nchannels_engaged;/* #of channels engaged with remote part */
+ struct xpc_channel *channels;/* array of channel structures */
+
+ void *local_GPs_base; /* base address of kmalloc'd space */
+ struct xpc_gp *local_GPs; /* local Get/Put values */
+ void *remote_GPs_base; /* base address of kmalloc'd space */
+ struct xpc_gp *remote_GPs;/* copy of remote partition's local Get/Put */
+ /* values */
+ u64 remote_GPs_pa; /* phys address of remote partition's local */
+ /* Get/Put values */
+
+
+ /* fields used to pass args when opening or closing a channel */
+
+ void *local_openclose_args_base; /* base address of kmalloc'd space */
+ struct xpc_openclose_args *local_openclose_args; /* local's args */
+ void *remote_openclose_args_base; /* base address of kmalloc'd space */
+ struct xpc_openclose_args *remote_openclose_args; /* copy of remote's */
+ /* args */
+ u64 remote_openclose_args_pa; /* phys addr of remote's args */
+
+
+ /* IPI sending, receiving and handling related fields */
+
+ int remote_IPI_nasid; /* nasid of where to send IPIs */
+ int remote_IPI_phys_cpuid; /* phys CPU ID of where to send IPIs */
+ AMO_t *remote_IPI_amo_va; /* address of remote IPI AMO_t structure */
+
+ AMO_t *local_IPI_amo_va; /* address of IPI AMO_t structure */
+ u64 local_IPI_amo; /* IPI amo flags yet to be handled */
+ char IPI_owner[8]; /* IPI owner's name */
+ struct timer_list dropped_IPI_timer; /* dropped IPI timer */
+
+ spinlock_t IPI_lock; /* IPI handler lock */
+
+
+ /* channel manager related fields */
+
+ atomic_t channel_mgr_requests; /* #of requests to activate chan mgr */
+ wait_queue_head_t channel_mgr_wq; /* channel mgr's wait queue */
+
+} ____cacheline_aligned;
+
+
+/* struct xpc_partition act_state values (for XPC HB) */
+
+#define XPC_P_INACTIVE 0x00 /* partition is not active */
+#define XPC_P_ACTIVATION_REQ 0x01 /* created thread to activate */
+#define XPC_P_ACTIVATING 0x02 /* activation thread started */
+#define XPC_P_ACTIVE 0x03 /* xpc_partition_up() was called */
+#define XPC_P_DEACTIVATING 0x04 /* partition deactivation initiated */
+
+
+#define XPC_DEACTIVATE_PARTITION(_p, _reason) \
+ xpc_deactivate_partition(__LINE__, (_p), (_reason))
+
+
+/* struct xpc_partition setup_state values */
+
+#define XPC_P_UNSET 0x00 /* infrastructure was never setup */
+#define XPC_P_SETUP 0x01 /* infrastructure is setup */
+#define XPC_P_WTEARDOWN 0x02 /* waiting to teardown infrastructure */
+#define XPC_P_TORNDOWN 0x03 /* infrastructure is torndown */
+
+
+
+/*
+ * struct xpc_partition IPI_timer #of seconds to wait before checking for
+ * dropped IPIs. These occur whenever an IPI amo write doesn't complete until
+ * after the IPI was received.
+ */
+#define XPC_P_DROPPED_IPI_WAIT (0.25 * HZ)
+
+
+/* number of seconds to wait for other partitions to disengage */
+#define XPC_DISENGAGE_REQUEST_DEFAULT_TIMELIMIT 90
+
+/* interval in seconds to print 'waiting disengagement' messages */
+#define XPC_DISENGAGE_PRINTMSG_INTERVAL 10
+
+
+#define XPC_PARTID(_p) ((partid_t) ((_p) - &xpc_partitions[0]))
+
+
+
+/* found in xp_main.c */
+extern struct xpc_registration xpc_registrations[];
+
+
+/* found in xpc_main.c */
+extern struct device *xpc_part;
+extern struct device *xpc_chan;
+extern int xpc_disengage_request_timelimit;
+extern int xpc_disengage_request_timedout;
+extern irqreturn_t xpc_notify_IRQ_handler(int, void *);
+extern void xpc_dropped_IPI_check(struct xpc_partition *);
+extern void xpc_activate_partition(struct xpc_partition *);
+extern void xpc_activate_kthreads(struct xpc_channel *, int);
+extern void xpc_create_kthreads(struct xpc_channel *, int, int);
+extern void xpc_disconnect_wait(int);
+
+
+/* found in xpc_partition.c */
+extern int xpc_exiting;
+extern struct xpc_vars *xpc_vars;
+extern struct xpc_rsvd_page *xpc_rsvd_page;
+extern struct xpc_vars_part *xpc_vars_part;
+extern struct xpc_partition xpc_partitions[XP_MAX_PARTITIONS + 1];
+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 void xpc_allow_IPI_ops(void);
+extern void xpc_restrict_IPI_ops(void);
+extern int xpc_identify_act_IRQ_sender(void);
+extern int xpc_partition_disengaged(struct xpc_partition *);
+extern enum xpc_retval xpc_mark_partition_active(struct xpc_partition *);
+extern void xpc_mark_partition_inactive(struct xpc_partition *);
+extern void xpc_discovery(void);
+extern void xpc_check_remote_hb(void);
+extern void xpc_deactivate_partition(const int, struct xpc_partition *,
+ enum xpc_retval);
+extern enum xpc_retval xpc_initiate_partid_to_nasids(partid_t, void *);
+
+
+/* found in xpc_channel.c */
+extern void xpc_initiate_connect(int);
+extern void xpc_initiate_disconnect(int);
+extern enum xpc_retval xpc_initiate_allocate(partid_t, int, u32, void **);
+extern enum xpc_retval xpc_initiate_send(partid_t, int, void *);
+extern enum xpc_retval xpc_initiate_send_notify(partid_t, int, void *,
+ xpc_notify_func, void *);
+extern void xpc_initiate_received(partid_t, int, void *);
+extern enum xpc_retval xpc_setup_infrastructure(struct xpc_partition *);
+extern enum xpc_retval xpc_pull_remote_vars_part(struct xpc_partition *);
+extern void xpc_process_channel_activity(struct xpc_partition *);
+extern void xpc_connected_callout(struct xpc_channel *);
+extern void xpc_deliver_msg(struct xpc_channel *);
+extern void xpc_disconnect_channel(const int, struct xpc_channel *,
+ enum xpc_retval, unsigned long *);
+extern void xpc_disconnect_callout(struct xpc_channel *, enum xpc_retval);
+extern void xpc_partition_going_down(struct xpc_partition *, enum xpc_retval);
+extern void xpc_teardown_infrastructure(struct xpc_partition *);
+
+
+
+static inline void
+xpc_wakeup_channel_mgr(struct xpc_partition *part)
+{
+ if (atomic_inc_return(&part->channel_mgr_requests) == 1) {
+ wake_up(&part->channel_mgr_wq);
+ }
+}
+
+
+
+/*
+ * These next two inlines are used to keep us from tearing down a channel's
+ * msg queues while a thread may be referencing them.
+ */
+static inline void
+xpc_msgqueue_ref(struct xpc_channel *ch)
+{
+ atomic_inc(&ch->references);
+}
+
+static inline void
+xpc_msgqueue_deref(struct xpc_channel *ch)
+{
+ s32 refs = atomic_dec_return(&ch->references);
+
+ DBUG_ON(refs < 0);
+ if (refs == 0) {
+ xpc_wakeup_channel_mgr(&xpc_partitions[ch->partid]);
+ }
+}
+
+
+
+#define XPC_DISCONNECT_CHANNEL(_ch, _reason, _irqflgs) \
+ xpc_disconnect_channel(__LINE__, _ch, _reason, _irqflgs)
+
+
+/*
+ * These two inlines are used to keep us from tearing down a partition's
+ * setup infrastructure while a thread may be referencing it.
+ */
+static inline void
+xpc_part_deref(struct xpc_partition *part)
+{
+ s32 refs = atomic_dec_return(&part->references);
+
+
+ DBUG_ON(refs < 0);
+ if (refs == 0 && part->setup_state == XPC_P_WTEARDOWN) {
+ wake_up(&part->teardown_wq);
+ }
+}
+
+static inline int
+xpc_part_ref(struct xpc_partition *part)
+{
+ int setup;
+
+
+ atomic_inc(&part->references);
+ setup = (part->setup_state == XPC_P_SETUP);
+ if (!setup) {
+ xpc_part_deref(part);
+ }
+ return setup;
+}
+
+
+
+/*
+ * The following macro is to be used for the setting of the reason and
+ * reason_line fields in both the struct xpc_channel and struct xpc_partition
+ * structures.
+ */
+#define XPC_SET_REASON(_p, _reason, _line) \
+ { \
+ (_p)->reason = _reason; \
+ (_p)->reason_line = _line; \
+ }
+
+
+
+/*
+ * This next set of inlines are used to keep track of when a partition is
+ * potentially engaged in accessing memory belonging to another partition.
+ */
+
+static inline void
+xpc_mark_partition_engaged(struct xpc_partition *part)
+{
+ unsigned long irq_flags;
+ AMO_t *amo = (AMO_t *) __va(part->remote_amos_page_pa +
+ (XPC_ENGAGED_PARTITIONS_AMO * sizeof(AMO_t)));
+
+
+ local_irq_save(irq_flags);
+
+ /* set bit corresponding to our partid in remote partition's AMO */
+ FETCHOP_STORE_OP(TO_AMO((u64) &amo->variable), FETCHOP_OR,
+ (1UL << sn_partition_id));
+ /*
+ * We must always use the nofault function regardless of whether we
+ * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
+ * didn't, we'd never know that the other partition is down and would
+ * keep sending IPIs and AMOs to it until the heartbeat times out.
+ */
+ (void) xp_nofault_PIOR((u64 *) GLOBAL_MMR_ADDR(NASID_GET(&amo->
+ variable), xp_nofault_PIOR_target));
+
+ local_irq_restore(irq_flags);
+}
+
+static inline void
+xpc_mark_partition_disengaged(struct xpc_partition *part)
+{
+ unsigned long irq_flags;
+ AMO_t *amo = (AMO_t *) __va(part->remote_amos_page_pa +
+ (XPC_ENGAGED_PARTITIONS_AMO * sizeof(AMO_t)));
+
+
+ local_irq_save(irq_flags);
+
+ /* clear bit corresponding to our partid in remote partition's AMO */
+ FETCHOP_STORE_OP(TO_AMO((u64) &amo->variable), FETCHOP_AND,
+ ~(1UL << sn_partition_id));
+ /*
+ * We must always use the nofault function regardless of whether we
+ * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
+ * didn't, we'd never know that the other partition is down and would
+ * keep sending IPIs and AMOs to it until the heartbeat times out.
+ */
+ (void) xp_nofault_PIOR((u64 *) GLOBAL_MMR_ADDR(NASID_GET(&amo->
+ variable), xp_nofault_PIOR_target));
+
+ local_irq_restore(irq_flags);
+}
+
+static inline void
+xpc_request_partition_disengage(struct xpc_partition *part)
+{
+ unsigned long irq_flags;
+ AMO_t *amo = (AMO_t *) __va(part->remote_amos_page_pa +
+ (XPC_DISENGAGE_REQUEST_AMO * sizeof(AMO_t)));
+
+
+ local_irq_save(irq_flags);
+
+ /* set bit corresponding to our partid in remote partition's AMO */
+ FETCHOP_STORE_OP(TO_AMO((u64) &amo->variable), FETCHOP_OR,
+ (1UL << sn_partition_id));
+ /*
+ * We must always use the nofault function regardless of whether we
+ * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
+ * didn't, we'd never know that the other partition is down and would
+ * keep sending IPIs and AMOs to it until the heartbeat times out.
+ */
+ (void) xp_nofault_PIOR((u64 *) GLOBAL_MMR_ADDR(NASID_GET(&amo->
+ variable), xp_nofault_PIOR_target));
+
+ local_irq_restore(irq_flags);
+}
+
+static inline void
+xpc_cancel_partition_disengage_request(struct xpc_partition *part)
+{
+ unsigned long irq_flags;
+ AMO_t *amo = (AMO_t *) __va(part->remote_amos_page_pa +
+ (XPC_DISENGAGE_REQUEST_AMO * sizeof(AMO_t)));
+
+
+ local_irq_save(irq_flags);
+
+ /* clear bit corresponding to our partid in remote partition's AMO */
+ FETCHOP_STORE_OP(TO_AMO((u64) &amo->variable), FETCHOP_AND,
+ ~(1UL << sn_partition_id));
+ /*
+ * We must always use the nofault function regardless of whether we
+ * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
+ * didn't, we'd never know that the other partition is down and would
+ * keep sending IPIs and AMOs to it until the heartbeat times out.
+ */
+ (void) xp_nofault_PIOR((u64 *) GLOBAL_MMR_ADDR(NASID_GET(&amo->
+ variable), xp_nofault_PIOR_target));
+
+ local_irq_restore(irq_flags);
+}
+
+static inline u64
+xpc_partition_engaged(u64 partid_mask)
+{
+ AMO_t *amo = xpc_vars->amos_page + XPC_ENGAGED_PARTITIONS_AMO;
+
+
+ /* return our partition's AMO variable ANDed with partid_mask */
+ return (FETCHOP_LOAD_OP(TO_AMO((u64) &amo->variable), FETCHOP_LOAD) &
+ partid_mask);
+}
+
+static inline u64
+xpc_partition_disengage_requested(u64 partid_mask)
+{
+ AMO_t *amo = xpc_vars->amos_page + XPC_DISENGAGE_REQUEST_AMO;
+
+
+ /* return our partition's AMO variable ANDed with partid_mask */
+ return (FETCHOP_LOAD_OP(TO_AMO((u64) &amo->variable), FETCHOP_LOAD) &
+ partid_mask);
+}
+
+static inline void
+xpc_clear_partition_engaged(u64 partid_mask)
+{
+ AMO_t *amo = xpc_vars->amos_page + XPC_ENGAGED_PARTITIONS_AMO;
+
+
+ /* clear bit(s) based on partid_mask in our partition's AMO */
+ FETCHOP_STORE_OP(TO_AMO((u64) &amo->variable), FETCHOP_AND,
+ ~partid_mask);
+}
+
+static inline void
+xpc_clear_partition_disengage_request(u64 partid_mask)
+{
+ AMO_t *amo = xpc_vars->amos_page + XPC_DISENGAGE_REQUEST_AMO;
+
+
+ /* clear bit(s) based on partid_mask in our partition's AMO */
+ FETCHOP_STORE_OP(TO_AMO((u64) &amo->variable), FETCHOP_AND,
+ ~partid_mask);
+}
+
+
+
+/*
+ * The following set of macros and inlines are used for the sending and
+ * receiving of IPIs (also known as IRQs). There are two flavors of IPIs,
+ * one that is associated with partition activity (SGI_XPC_ACTIVATE) and
+ * the other that is associated with channel activity (SGI_XPC_NOTIFY).
+ */
+
+static inline u64
+xpc_IPI_receive(AMO_t *amo)
+{
+ return FETCHOP_LOAD_OP(TO_AMO((u64) &amo->variable), FETCHOP_CLEAR);
+}
+
+
+static inline enum xpc_retval
+xpc_IPI_send(AMO_t *amo, u64 flag, int nasid, int phys_cpuid, int vector)
+{
+ int ret = 0;
+ unsigned long irq_flags;
+
+
+ local_irq_save(irq_flags);
+
+ FETCHOP_STORE_OP(TO_AMO((u64) &amo->variable), FETCHOP_OR, flag);
+ sn_send_IPI_phys(nasid, phys_cpuid, vector, 0);
+
+ /*
+ * We must always use the nofault function regardless of whether we
+ * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
+ * didn't, we'd never know that the other partition is down and would
+ * keep sending IPIs and AMOs to it until the heartbeat times out.
+ */
+ ret = xp_nofault_PIOR((u64 *) GLOBAL_MMR_ADDR(NASID_GET(&amo->variable),
+ xp_nofault_PIOR_target));
+
+ local_irq_restore(irq_flags);
+
+ return ((ret == 0) ? xpcSuccess : xpcPioReadError);
+}
+
+
+/*
+ * IPIs associated with SGI_XPC_ACTIVATE IRQ.
+ */
+
+/*
+ * Flag the appropriate AMO variable and send an IPI to the specified node.
+ */
+static inline void
+xpc_activate_IRQ_send(u64 amos_page_pa, int from_nasid, int to_nasid,
+ int to_phys_cpuid)
+{
+ int w_index = XPC_NASID_W_INDEX(from_nasid);
+ int b_index = XPC_NASID_B_INDEX(from_nasid);
+ AMO_t *amos = (AMO_t *) __va(amos_page_pa +
+ (XPC_ACTIVATE_IRQ_AMOS * sizeof(AMO_t)));
+
+
+ (void) xpc_IPI_send(&amos[w_index], (1UL << b_index), to_nasid,
+ to_phys_cpuid, SGI_XPC_ACTIVATE);
+}
+
+static inline void
+xpc_IPI_send_activate(struct xpc_vars *vars)
+{
+ xpc_activate_IRQ_send(vars->amos_page_pa, cnodeid_to_nasid(0),
+ vars->act_nasid, vars->act_phys_cpuid);
+}
+
+static inline void
+xpc_IPI_send_activated(struct xpc_partition *part)
+{
+ xpc_activate_IRQ_send(part->remote_amos_page_pa, cnodeid_to_nasid(0),
+ part->remote_act_nasid, part->remote_act_phys_cpuid);
+}
+
+static inline void
+xpc_IPI_send_reactivate(struct xpc_partition *part)
+{
+ xpc_activate_IRQ_send(xpc_vars->amos_page_pa, part->reactivate_nasid,
+ xpc_vars->act_nasid, xpc_vars->act_phys_cpuid);
+}
+
+static inline void
+xpc_IPI_send_disengage(struct xpc_partition *part)
+{
+ xpc_activate_IRQ_send(part->remote_amos_page_pa, cnodeid_to_nasid(0),
+ part->remote_act_nasid, part->remote_act_phys_cpuid);
+}
+
+
+/*
+ * IPIs associated with SGI_XPC_NOTIFY IRQ.
+ */
+
+/*
+ * Send an IPI to the remote partition that is associated with the
+ * specified channel.
+ */
+#define XPC_NOTIFY_IRQ_SEND(_ch, _ipi_f, _irq_f) \
+ xpc_notify_IRQ_send(_ch, _ipi_f, #_ipi_f, _irq_f)
+
+static inline void
+xpc_notify_IRQ_send(struct xpc_channel *ch, u8 ipi_flag, char *ipi_flag_string,
+ unsigned long *irq_flags)
+{
+ struct xpc_partition *part = &xpc_partitions[ch->partid];
+ enum xpc_retval ret;
+
+
+ if (likely(part->act_state != XPC_P_DEACTIVATING)) {
+ ret = xpc_IPI_send(part->remote_IPI_amo_va,
+ (u64) ipi_flag << (ch->number * 8),
+ part->remote_IPI_nasid,
+ part->remote_IPI_phys_cpuid,
+ SGI_XPC_NOTIFY);
+ dev_dbg(xpc_chan, "%s sent to partid=%d, channel=%d, ret=%d\n",
+ ipi_flag_string, ch->partid, ch->number, ret);
+ if (unlikely(ret != xpcSuccess)) {
+ if (irq_flags != NULL) {
+ spin_unlock_irqrestore(&ch->lock, *irq_flags);
+ }
+ XPC_DEACTIVATE_PARTITION(part, ret);
+ if (irq_flags != NULL) {
+ spin_lock_irqsave(&ch->lock, *irq_flags);
+ }
+ }
+ }
+}
+
+
+/*
+ * Make it look like the remote partition, which is associated with the
+ * specified channel, sent us an IPI. This faked IPI will be handled
+ * by xpc_dropped_IPI_check().
+ */
+#define XPC_NOTIFY_IRQ_SEND_LOCAL(_ch, _ipi_f) \
+ xpc_notify_IRQ_send_local(_ch, _ipi_f, #_ipi_f)
+
+static inline void
+xpc_notify_IRQ_send_local(struct xpc_channel *ch, u8 ipi_flag,
+ char *ipi_flag_string)
+{
+ struct xpc_partition *part = &xpc_partitions[ch->partid];
+
+
+ FETCHOP_STORE_OP(TO_AMO((u64) &part->local_IPI_amo_va->variable),
+ FETCHOP_OR, ((u64) ipi_flag << (ch->number * 8)));
+ dev_dbg(xpc_chan, "%s sent local from partid=%d, channel=%d\n",
+ ipi_flag_string, ch->partid, ch->number);
+}
+
+
+/*
+ * The sending and receiving of IPIs includes the setting of an AMO variable
+ * to indicate the reason the IPI was sent. The 64-bit variable is divided
+ * up into eight bytes, ordered from right to left. Byte zero pertains to
+ * channel 0, byte one to channel 1, and so on. Each byte is described by
+ * the following IPI flags.
+ */
+
+#define XPC_IPI_CLOSEREQUEST 0x01
+#define XPC_IPI_CLOSEREPLY 0x02
+#define XPC_IPI_OPENREQUEST 0x04
+#define XPC_IPI_OPENREPLY 0x08
+#define XPC_IPI_MSGREQUEST 0x10
+
+
+/* given an AMO variable and a channel#, get its associated IPI flags */
+#define XPC_GET_IPI_FLAGS(_amo, _c) ((u8) (((_amo) >> ((_c) * 8)) & 0xff))
+#define XPC_SET_IPI_FLAGS(_amo, _c, _f) (_amo) |= ((u64) (_f) << ((_c) * 8))
+
+#define XPC_ANY_OPENCLOSE_IPI_FLAGS_SET(_amo) ((_amo) & __IA64_UL_CONST(0x0f0f0f0f0f0f0f0f))
+#define XPC_ANY_MSG_IPI_FLAGS_SET(_amo) ((_amo) & __IA64_UL_CONST(0x1010101010101010))
+
+
+static inline void
+xpc_IPI_send_closerequest(struct xpc_channel *ch, unsigned long *irq_flags)
+{
+ struct xpc_openclose_args *args = ch->local_openclose_args;
+
+
+ args->reason = ch->reason;
+
+ XPC_NOTIFY_IRQ_SEND(ch, XPC_IPI_CLOSEREQUEST, irq_flags);
+}
+
+static inline void
+xpc_IPI_send_closereply(struct xpc_channel *ch, unsigned long *irq_flags)
+{
+ XPC_NOTIFY_IRQ_SEND(ch, XPC_IPI_CLOSEREPLY, irq_flags);
+}
+
+static inline void
+xpc_IPI_send_openrequest(struct xpc_channel *ch, unsigned long *irq_flags)
+{
+ struct xpc_openclose_args *args = ch->local_openclose_args;
+
+
+ args->msg_size = ch->msg_size;
+ args->local_nentries = ch->local_nentries;
+
+ XPC_NOTIFY_IRQ_SEND(ch, XPC_IPI_OPENREQUEST, irq_flags);
+}
+
+static inline void
+xpc_IPI_send_openreply(struct xpc_channel *ch, unsigned long *irq_flags)
+{
+ struct xpc_openclose_args *args = ch->local_openclose_args;
+
+
+ args->remote_nentries = ch->remote_nentries;
+ args->local_nentries = ch->local_nentries;
+ args->local_msgqueue_pa = __pa(ch->local_msgqueue);
+
+ XPC_NOTIFY_IRQ_SEND(ch, XPC_IPI_OPENREPLY, irq_flags);
+}
+
+static inline void
+xpc_IPI_send_msgrequest(struct xpc_channel *ch)
+{
+ XPC_NOTIFY_IRQ_SEND(ch, XPC_IPI_MSGREQUEST, NULL);
+}
+
+static inline void
+xpc_IPI_send_local_msgrequest(struct xpc_channel *ch)
+{
+ XPC_NOTIFY_IRQ_SEND_LOCAL(ch, XPC_IPI_MSGREQUEST);
+}
+
+
+/*
+ * Memory for XPC's AMO variables is allocated by the MSPEC driver. These
+ * pages are located in the lowest granule. The lowest granule uses 4k pages
+ * for cached references and an alternate TLB handler to never provide a
+ * cacheable mapping for the entire region. This will prevent speculative
+ * reading of cached copies of our lines from being issued which will cause
+ * a PI FSB Protocol error to be generated by the SHUB. For XPC, we need 64
+ * AMO variables (based on XP_MAX_PARTITIONS) for message notification and an
+ * additional 128 AMO variables (based on XP_NASID_MASK_WORDS) for partition
+ * activation and 2 AMO variables for partition deactivation.
+ */
+static inline AMO_t *
+xpc_IPI_init(int index)
+{
+ AMO_t *amo = xpc_vars->amos_page + index;
+
+
+ (void) xpc_IPI_receive(amo); /* clear AMO variable */
+ return amo;
+}
+
+
+
+static inline enum xpc_retval
+xpc_map_bte_errors(bte_result_t error)
+{
+ if (error == BTE_SUCCESS)
+ return xpcSuccess;
+
+ if (is_shub2()) {
+ if (BTE_VALID_SH2_ERROR(error))
+ return xpcBteSh2Start + error;
+ return xpcBteUnmappedError;
+ }
+ switch (error) {
+ case BTE_SUCCESS: return xpcSuccess;
+ case BTEFAIL_DIR: return xpcBteDirectoryError;
+ case BTEFAIL_POISON: return xpcBtePoisonError;
+ case BTEFAIL_WERR: return xpcBteWriteError;
+ case BTEFAIL_ACCESS: return xpcBteAccessError;
+ case BTEFAIL_PWERR: return xpcBtePWriteError;
+ case BTEFAIL_PRERR: return xpcBtePReadError;
+ case BTEFAIL_TOUT: return xpcBteTimeOutError;
+ case BTEFAIL_XTERR: return xpcBteXtalkError;
+ case BTEFAIL_NOTAVAIL: return xpcBteNotAvailable;
+ default: return xpcBteUnmappedError;
+ }
+}
+
+
+
+/*
+ * Check to see if there is any channel activity to/from the specified
+ * partition.
+ */
+static inline void
+xpc_check_for_channel_activity(struct xpc_partition *part)
+{
+ u64 IPI_amo;
+ unsigned long irq_flags;
+
+
+ IPI_amo = xpc_IPI_receive(part->local_IPI_amo_va);
+ if (IPI_amo == 0) {
+ return;
+ }
+
+ spin_lock_irqsave(&part->IPI_lock, irq_flags);
+ part->local_IPI_amo |= IPI_amo;
+ spin_unlock_irqrestore(&part->IPI_lock, irq_flags);
+
+ dev_dbg(xpc_chan, "received IPI from partid=%d, IPI_amo=0x%lx\n",
+ XPC_PARTID(part), IPI_amo);
+
+ xpc_wakeup_channel_mgr(part);
+}
+
+
+#endif /* _DRIVERS_MISC_SGIXP_XPC_H */
+