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-rw-r--r--drivers/misc/sgi-gru/grukservices.c1159
1 files changed, 1159 insertions, 0 deletions
diff --git a/drivers/misc/sgi-gru/grukservices.c b/drivers/misc/sgi-gru/grukservices.c
new file mode 100644
index 0000000000..37e804bbb1
--- /dev/null
+++ b/drivers/misc/sgi-gru/grukservices.c
@@ -0,0 +1,1159 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * SN Platform GRU Driver
+ *
+ * KERNEL SERVICES THAT USE THE GRU
+ *
+ * Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved.
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/miscdevice.h>
+#include <linux/proc_fs.h>
+#include <linux/interrupt.h>
+#include <linux/sync_core.h>
+#include <linux/uaccess.h>
+#include <linux/delay.h>
+#include <linux/export.h>
+#include <asm/io_apic.h>
+#include "gru.h"
+#include "grulib.h"
+#include "grutables.h"
+#include "grukservices.h"
+#include "gru_instructions.h"
+#include <asm/uv/uv_hub.h>
+
+/*
+ * Kernel GRU Usage
+ *
+ * The following is an interim algorithm for management of kernel GRU
+ * resources. This will likely be replaced when we better understand the
+ * kernel/user requirements.
+ *
+ * Blade percpu resources reserved for kernel use. These resources are
+ * reserved whenever the kernel context for the blade is loaded. Note
+ * that the kernel context is not guaranteed to be always available. It is
+ * loaded on demand & can be stolen by a user if the user demand exceeds the
+ * kernel demand. The kernel can always reload the kernel context but
+ * a SLEEP may be required!!!.
+ *
+ * Async Overview:
+ *
+ * Each blade has one "kernel context" that owns GRU kernel resources
+ * located on the blade. Kernel drivers use GRU resources in this context
+ * for sending messages, zeroing memory, etc.
+ *
+ * The kernel context is dynamically loaded on demand. If it is not in
+ * use by the kernel, the kernel context can be unloaded & given to a user.
+ * The kernel context will be reloaded when needed. This may require that
+ * a context be stolen from a user.
+ * NOTE: frequent unloading/reloading of the kernel context is
+ * expensive. We are depending on batch schedulers, cpusets, sane
+ * drivers or some other mechanism to prevent the need for frequent
+ * stealing/reloading.
+ *
+ * The kernel context consists of two parts:
+ * - 1 CB & a few DSRs that are reserved for each cpu on the blade.
+ * Each cpu has it's own private resources & does not share them
+ * with other cpus. These resources are used serially, ie,
+ * locked, used & unlocked on each call to a function in
+ * grukservices.
+ * (Now that we have dynamic loading of kernel contexts, I
+ * may rethink this & allow sharing between cpus....)
+ *
+ * - Additional resources can be reserved long term & used directly
+ * by UV drivers located in the kernel. Drivers using these GRU
+ * resources can use asynchronous GRU instructions that send
+ * interrupts on completion.
+ * - these resources must be explicitly locked/unlocked
+ * - locked resources prevent (obviously) the kernel
+ * context from being unloaded.
+ * - drivers using these resource directly issue their own
+ * GRU instruction and must wait/check completion.
+ *
+ * When these resources are reserved, the caller can optionally
+ * associate a wait_queue with the resources and use asynchronous
+ * GRU instructions. When an async GRU instruction completes, the
+ * driver will do a wakeup on the event.
+ *
+ */
+
+
+#define ASYNC_HAN_TO_BID(h) ((h) - 1)
+#define ASYNC_BID_TO_HAN(b) ((b) + 1)
+#define ASYNC_HAN_TO_BS(h) gru_base[ASYNC_HAN_TO_BID(h)]
+
+#define GRU_NUM_KERNEL_CBR 1
+#define GRU_NUM_KERNEL_DSR_BYTES 256
+#define GRU_NUM_KERNEL_DSR_CL (GRU_NUM_KERNEL_DSR_BYTES / \
+ GRU_CACHE_LINE_BYTES)
+
+/* GRU instruction attributes for all instructions */
+#define IMA IMA_CB_DELAY
+
+/* GRU cacheline size is always 64 bytes - even on arches with 128 byte lines */
+#define __gru_cacheline_aligned__ \
+ __attribute__((__aligned__(GRU_CACHE_LINE_BYTES)))
+
+#define MAGIC 0x1234567887654321UL
+
+/* Default retry count for GRU errors on kernel instructions */
+#define EXCEPTION_RETRY_LIMIT 3
+
+/* Status of message queue sections */
+#define MQS_EMPTY 0
+#define MQS_FULL 1
+#define MQS_NOOP 2
+
+/*----------------- RESOURCE MANAGEMENT -------------------------------------*/
+/* optimized for x86_64 */
+struct message_queue {
+ union gru_mesqhead head __gru_cacheline_aligned__; /* CL 0 */
+ int qlines; /* DW 1 */
+ long hstatus[2];
+ void *next __gru_cacheline_aligned__;/* CL 1 */
+ void *limit;
+ void *start;
+ void *start2;
+ char data ____cacheline_aligned; /* CL 2 */
+};
+
+/* First word in every message - used by mesq interface */
+struct message_header {
+ char present;
+ char present2;
+ char lines;
+ char fill;
+};
+
+#define HSTATUS(mq, h) ((mq) + offsetof(struct message_queue, hstatus[h]))
+
+/*
+ * Reload the blade's kernel context into a GRU chiplet. Called holding
+ * the bs_kgts_sema for READ. Will steal user contexts if necessary.
+ */
+static void gru_load_kernel_context(struct gru_blade_state *bs, int blade_id)
+{
+ struct gru_state *gru;
+ struct gru_thread_state *kgts;
+ void *vaddr;
+ int ctxnum, ncpus;
+
+ up_read(&bs->bs_kgts_sema);
+ down_write(&bs->bs_kgts_sema);
+
+ if (!bs->bs_kgts) {
+ do {
+ bs->bs_kgts = gru_alloc_gts(NULL, 0, 0, 0, 0, 0);
+ if (!IS_ERR(bs->bs_kgts))
+ break;
+ msleep(1);
+ } while (true);
+ bs->bs_kgts->ts_user_blade_id = blade_id;
+ }
+ kgts = bs->bs_kgts;
+
+ if (!kgts->ts_gru) {
+ STAT(load_kernel_context);
+ ncpus = uv_blade_nr_possible_cpus(blade_id);
+ kgts->ts_cbr_au_count = GRU_CB_COUNT_TO_AU(
+ GRU_NUM_KERNEL_CBR * ncpus + bs->bs_async_cbrs);
+ kgts->ts_dsr_au_count = GRU_DS_BYTES_TO_AU(
+ GRU_NUM_KERNEL_DSR_BYTES * ncpus +
+ bs->bs_async_dsr_bytes);
+ while (!gru_assign_gru_context(kgts)) {
+ msleep(1);
+ gru_steal_context(kgts);
+ }
+ gru_load_context(kgts);
+ gru = bs->bs_kgts->ts_gru;
+ vaddr = gru->gs_gru_base_vaddr;
+ ctxnum = kgts->ts_ctxnum;
+ bs->kernel_cb = get_gseg_base_address_cb(vaddr, ctxnum, 0);
+ bs->kernel_dsr = get_gseg_base_address_ds(vaddr, ctxnum, 0);
+ }
+ downgrade_write(&bs->bs_kgts_sema);
+}
+
+/*
+ * Free all kernel contexts that are not currently in use.
+ * Returns 0 if all freed, else number of inuse context.
+ */
+static int gru_free_kernel_contexts(void)
+{
+ struct gru_blade_state *bs;
+ struct gru_thread_state *kgts;
+ int bid, ret = 0;
+
+ for (bid = 0; bid < GRU_MAX_BLADES; bid++) {
+ bs = gru_base[bid];
+ if (!bs)
+ continue;
+
+ /* Ignore busy contexts. Don't want to block here. */
+ if (down_write_trylock(&bs->bs_kgts_sema)) {
+ kgts = bs->bs_kgts;
+ if (kgts && kgts->ts_gru)
+ gru_unload_context(kgts, 0);
+ bs->bs_kgts = NULL;
+ up_write(&bs->bs_kgts_sema);
+ kfree(kgts);
+ } else {
+ ret++;
+ }
+ }
+ return ret;
+}
+
+/*
+ * Lock & load the kernel context for the specified blade.
+ */
+static struct gru_blade_state *gru_lock_kernel_context(int blade_id)
+{
+ struct gru_blade_state *bs;
+ int bid;
+
+ STAT(lock_kernel_context);
+again:
+ bid = blade_id < 0 ? uv_numa_blade_id() : blade_id;
+ bs = gru_base[bid];
+
+ /* Handle the case where migration occurred while waiting for the sema */
+ down_read(&bs->bs_kgts_sema);
+ if (blade_id < 0 && bid != uv_numa_blade_id()) {
+ up_read(&bs->bs_kgts_sema);
+ goto again;
+ }
+ if (!bs->bs_kgts || !bs->bs_kgts->ts_gru)
+ gru_load_kernel_context(bs, bid);
+ return bs;
+
+}
+
+/*
+ * Unlock the kernel context for the specified blade. Context is not
+ * unloaded but may be stolen before next use.
+ */
+static void gru_unlock_kernel_context(int blade_id)
+{
+ struct gru_blade_state *bs;
+
+ bs = gru_base[blade_id];
+ up_read(&bs->bs_kgts_sema);
+ STAT(unlock_kernel_context);
+}
+
+/*
+ * Reserve & get pointers to the DSR/CBRs reserved for the current cpu.
+ * - returns with preemption disabled
+ */
+static int gru_get_cpu_resources(int dsr_bytes, void **cb, void **dsr)
+{
+ struct gru_blade_state *bs;
+ int lcpu;
+
+ BUG_ON(dsr_bytes > GRU_NUM_KERNEL_DSR_BYTES);
+ preempt_disable();
+ bs = gru_lock_kernel_context(-1);
+ lcpu = uv_blade_processor_id();
+ *cb = bs->kernel_cb + lcpu * GRU_HANDLE_STRIDE;
+ *dsr = bs->kernel_dsr + lcpu * GRU_NUM_KERNEL_DSR_BYTES;
+ return 0;
+}
+
+/*
+ * Free the current cpus reserved DSR/CBR resources.
+ */
+static void gru_free_cpu_resources(void *cb, void *dsr)
+{
+ gru_unlock_kernel_context(uv_numa_blade_id());
+ preempt_enable();
+}
+
+/*
+ * Reserve GRU resources to be used asynchronously.
+ * Note: currently supports only 1 reservation per blade.
+ *
+ * input:
+ * blade_id - blade on which resources should be reserved
+ * cbrs - number of CBRs
+ * dsr_bytes - number of DSR bytes needed
+ * output:
+ * handle to identify resource
+ * (0 = async resources already reserved)
+ */
+unsigned long gru_reserve_async_resources(int blade_id, int cbrs, int dsr_bytes,
+ struct completion *cmp)
+{
+ struct gru_blade_state *bs;
+ struct gru_thread_state *kgts;
+ int ret = 0;
+
+ bs = gru_base[blade_id];
+
+ down_write(&bs->bs_kgts_sema);
+
+ /* Verify no resources already reserved */
+ if (bs->bs_async_dsr_bytes + bs->bs_async_cbrs)
+ goto done;
+ bs->bs_async_dsr_bytes = dsr_bytes;
+ bs->bs_async_cbrs = cbrs;
+ bs->bs_async_wq = cmp;
+ kgts = bs->bs_kgts;
+
+ /* Resources changed. Unload context if already loaded */
+ if (kgts && kgts->ts_gru)
+ gru_unload_context(kgts, 0);
+ ret = ASYNC_BID_TO_HAN(blade_id);
+
+done:
+ up_write(&bs->bs_kgts_sema);
+ return ret;
+}
+
+/*
+ * Release async resources previously reserved.
+ *
+ * input:
+ * han - handle to identify resources
+ */
+void gru_release_async_resources(unsigned long han)
+{
+ struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han);
+
+ down_write(&bs->bs_kgts_sema);
+ bs->bs_async_dsr_bytes = 0;
+ bs->bs_async_cbrs = 0;
+ bs->bs_async_wq = NULL;
+ up_write(&bs->bs_kgts_sema);
+}
+
+/*
+ * Wait for async GRU instructions to complete.
+ *
+ * input:
+ * han - handle to identify resources
+ */
+void gru_wait_async_cbr(unsigned long han)
+{
+ struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han);
+
+ wait_for_completion(bs->bs_async_wq);
+ mb();
+}
+
+/*
+ * Lock previous reserved async GRU resources
+ *
+ * input:
+ * han - handle to identify resources
+ * output:
+ * cb - pointer to first CBR
+ * dsr - pointer to first DSR
+ */
+void gru_lock_async_resource(unsigned long han, void **cb, void **dsr)
+{
+ struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han);
+ int blade_id = ASYNC_HAN_TO_BID(han);
+ int ncpus;
+
+ gru_lock_kernel_context(blade_id);
+ ncpus = uv_blade_nr_possible_cpus(blade_id);
+ if (cb)
+ *cb = bs->kernel_cb + ncpus * GRU_HANDLE_STRIDE;
+ if (dsr)
+ *dsr = bs->kernel_dsr + ncpus * GRU_NUM_KERNEL_DSR_BYTES;
+}
+
+/*
+ * Unlock previous reserved async GRU resources
+ *
+ * input:
+ * han - handle to identify resources
+ */
+void gru_unlock_async_resource(unsigned long han)
+{
+ int blade_id = ASYNC_HAN_TO_BID(han);
+
+ gru_unlock_kernel_context(blade_id);
+}
+
+/*----------------------------------------------------------------------*/
+int gru_get_cb_exception_detail(void *cb,
+ struct control_block_extended_exc_detail *excdet)
+{
+ struct gru_control_block_extended *cbe;
+ struct gru_thread_state *kgts = NULL;
+ unsigned long off;
+ int cbrnum, bid;
+
+ /*
+ * Locate kgts for cb. This algorithm is SLOW but
+ * this function is rarely called (ie., almost never).
+ * Performance does not matter.
+ */
+ for_each_possible_blade(bid) {
+ if (!gru_base[bid])
+ break;
+ kgts = gru_base[bid]->bs_kgts;
+ if (!kgts || !kgts->ts_gru)
+ continue;
+ off = cb - kgts->ts_gru->gs_gru_base_vaddr;
+ if (off < GRU_SIZE)
+ break;
+ kgts = NULL;
+ }
+ BUG_ON(!kgts);
+ cbrnum = thread_cbr_number(kgts, get_cb_number(cb));
+ cbe = get_cbe(GRUBASE(cb), cbrnum);
+ gru_flush_cache(cbe); /* CBE not coherent */
+ sync_core();
+ excdet->opc = cbe->opccpy;
+ excdet->exopc = cbe->exopccpy;
+ excdet->ecause = cbe->ecause;
+ excdet->exceptdet0 = cbe->idef1upd;
+ excdet->exceptdet1 = cbe->idef3upd;
+ gru_flush_cache(cbe);
+ return 0;
+}
+
+static char *gru_get_cb_exception_detail_str(int ret, void *cb,
+ char *buf, int size)
+{
+ struct gru_control_block_status *gen = cb;
+ struct control_block_extended_exc_detail excdet;
+
+ if (ret > 0 && gen->istatus == CBS_EXCEPTION) {
+ gru_get_cb_exception_detail(cb, &excdet);
+ snprintf(buf, size,
+ "GRU:%d exception: cb %p, opc %d, exopc %d, ecause 0x%x,"
+ "excdet0 0x%lx, excdet1 0x%x", smp_processor_id(),
+ gen, excdet.opc, excdet.exopc, excdet.ecause,
+ excdet.exceptdet0, excdet.exceptdet1);
+ } else {
+ snprintf(buf, size, "No exception");
+ }
+ return buf;
+}
+
+static int gru_wait_idle_or_exception(struct gru_control_block_status *gen)
+{
+ while (gen->istatus >= CBS_ACTIVE) {
+ cpu_relax();
+ barrier();
+ }
+ return gen->istatus;
+}
+
+static int gru_retry_exception(void *cb)
+{
+ struct gru_control_block_status *gen = cb;
+ struct control_block_extended_exc_detail excdet;
+ int retry = EXCEPTION_RETRY_LIMIT;
+
+ while (1) {
+ if (gru_wait_idle_or_exception(gen) == CBS_IDLE)
+ return CBS_IDLE;
+ if (gru_get_cb_message_queue_substatus(cb))
+ return CBS_EXCEPTION;
+ gru_get_cb_exception_detail(cb, &excdet);
+ if ((excdet.ecause & ~EXCEPTION_RETRY_BITS) ||
+ (excdet.cbrexecstatus & CBR_EXS_ABORT_OCC))
+ break;
+ if (retry-- == 0)
+ break;
+ gen->icmd = 1;
+ gru_flush_cache(gen);
+ }
+ return CBS_EXCEPTION;
+}
+
+int gru_check_status_proc(void *cb)
+{
+ struct gru_control_block_status *gen = cb;
+ int ret;
+
+ ret = gen->istatus;
+ if (ret == CBS_EXCEPTION)
+ ret = gru_retry_exception(cb);
+ rmb();
+ return ret;
+
+}
+
+int gru_wait_proc(void *cb)
+{
+ struct gru_control_block_status *gen = cb;
+ int ret;
+
+ ret = gru_wait_idle_or_exception(gen);
+ if (ret == CBS_EXCEPTION)
+ ret = gru_retry_exception(cb);
+ rmb();
+ return ret;
+}
+
+static void gru_abort(int ret, void *cb, char *str)
+{
+ char buf[GRU_EXC_STR_SIZE];
+
+ panic("GRU FATAL ERROR: %s - %s\n", str,
+ gru_get_cb_exception_detail_str(ret, cb, buf, sizeof(buf)));
+}
+
+void gru_wait_abort_proc(void *cb)
+{
+ int ret;
+
+ ret = gru_wait_proc(cb);
+ if (ret)
+ gru_abort(ret, cb, "gru_wait_abort");
+}
+
+
+/*------------------------------ MESSAGE QUEUES -----------------------------*/
+
+/* Internal status . These are NOT returned to the user. */
+#define MQIE_AGAIN -1 /* try again */
+
+
+/*
+ * Save/restore the "present" flag that is in the second line of 2-line
+ * messages
+ */
+static inline int get_present2(void *p)
+{
+ struct message_header *mhdr = p + GRU_CACHE_LINE_BYTES;
+ return mhdr->present;
+}
+
+static inline void restore_present2(void *p, int val)
+{
+ struct message_header *mhdr = p + GRU_CACHE_LINE_BYTES;
+ mhdr->present = val;
+}
+
+/*
+ * Create a message queue.
+ * qlines - message queue size in cache lines. Includes 2-line header.
+ */
+int gru_create_message_queue(struct gru_message_queue_desc *mqd,
+ void *p, unsigned int bytes, int nasid, int vector, int apicid)
+{
+ struct message_queue *mq = p;
+ unsigned int qlines;
+
+ qlines = bytes / GRU_CACHE_LINE_BYTES - 2;
+ memset(mq, 0, bytes);
+ mq->start = &mq->data;
+ mq->start2 = &mq->data + (qlines / 2 - 1) * GRU_CACHE_LINE_BYTES;
+ mq->next = &mq->data;
+ mq->limit = &mq->data + (qlines - 2) * GRU_CACHE_LINE_BYTES;
+ mq->qlines = qlines;
+ mq->hstatus[0] = 0;
+ mq->hstatus[1] = 1;
+ mq->head = gru_mesq_head(2, qlines / 2 + 1);
+ mqd->mq = mq;
+ mqd->mq_gpa = uv_gpa(mq);
+ mqd->qlines = qlines;
+ mqd->interrupt_pnode = nasid >> 1;
+ mqd->interrupt_vector = vector;
+ mqd->interrupt_apicid = apicid;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(gru_create_message_queue);
+
+/*
+ * Send a NOOP message to a message queue
+ * Returns:
+ * 0 - if queue is full after the send. This is the normal case
+ * but various races can change this.
+ * -1 - if mesq sent successfully but queue not full
+ * >0 - unexpected error. MQE_xxx returned
+ */
+static int send_noop_message(void *cb, struct gru_message_queue_desc *mqd,
+ void *mesg)
+{
+ const struct message_header noop_header = {
+ .present = MQS_NOOP, .lines = 1};
+ unsigned long m;
+ int substatus, ret;
+ struct message_header save_mhdr, *mhdr = mesg;
+
+ STAT(mesq_noop);
+ save_mhdr = *mhdr;
+ *mhdr = noop_header;
+ gru_mesq(cb, mqd->mq_gpa, gru_get_tri(mhdr), 1, IMA);
+ ret = gru_wait(cb);
+
+ if (ret) {
+ substatus = gru_get_cb_message_queue_substatus(cb);
+ switch (substatus) {
+ case CBSS_NO_ERROR:
+ STAT(mesq_noop_unexpected_error);
+ ret = MQE_UNEXPECTED_CB_ERR;
+ break;
+ case CBSS_LB_OVERFLOWED:
+ STAT(mesq_noop_lb_overflow);
+ ret = MQE_CONGESTION;
+ break;
+ case CBSS_QLIMIT_REACHED:
+ STAT(mesq_noop_qlimit_reached);
+ ret = 0;
+ break;
+ case CBSS_AMO_NACKED:
+ STAT(mesq_noop_amo_nacked);
+ ret = MQE_CONGESTION;
+ break;
+ case CBSS_PUT_NACKED:
+ STAT(mesq_noop_put_nacked);
+ m = mqd->mq_gpa + (gru_get_amo_value_head(cb) << 6);
+ gru_vstore(cb, m, gru_get_tri(mesg), XTYPE_CL, 1, 1,
+ IMA);
+ if (gru_wait(cb) == CBS_IDLE)
+ ret = MQIE_AGAIN;
+ else
+ ret = MQE_UNEXPECTED_CB_ERR;
+ break;
+ case CBSS_PAGE_OVERFLOW:
+ STAT(mesq_noop_page_overflow);
+ fallthrough;
+ default:
+ BUG();
+ }
+ }
+ *mhdr = save_mhdr;
+ return ret;
+}
+
+/*
+ * Handle a gru_mesq full.
+ */
+static int send_message_queue_full(void *cb, struct gru_message_queue_desc *mqd,
+ void *mesg, int lines)
+{
+ union gru_mesqhead mqh;
+ unsigned int limit, head;
+ unsigned long avalue;
+ int half, qlines;
+
+ /* Determine if switching to first/second half of q */
+ avalue = gru_get_amo_value(cb);
+ head = gru_get_amo_value_head(cb);
+ limit = gru_get_amo_value_limit(cb);
+
+ qlines = mqd->qlines;
+ half = (limit != qlines);
+
+ if (half)
+ mqh = gru_mesq_head(qlines / 2 + 1, qlines);
+ else
+ mqh = gru_mesq_head(2, qlines / 2 + 1);
+
+ /* Try to get lock for switching head pointer */
+ gru_gamir(cb, EOP_IR_CLR, HSTATUS(mqd->mq_gpa, half), XTYPE_DW, IMA);
+ if (gru_wait(cb) != CBS_IDLE)
+ goto cberr;
+ if (!gru_get_amo_value(cb)) {
+ STAT(mesq_qf_locked);
+ return MQE_QUEUE_FULL;
+ }
+
+ /* Got the lock. Send optional NOP if queue not full, */
+ if (head != limit) {
+ if (send_noop_message(cb, mqd, mesg)) {
+ gru_gamir(cb, EOP_IR_INC, HSTATUS(mqd->mq_gpa, half),
+ XTYPE_DW, IMA);
+ if (gru_wait(cb) != CBS_IDLE)
+ goto cberr;
+ STAT(mesq_qf_noop_not_full);
+ return MQIE_AGAIN;
+ }
+ avalue++;
+ }
+
+ /* Then flip queuehead to other half of queue. */
+ gru_gamer(cb, EOP_ERR_CSWAP, mqd->mq_gpa, XTYPE_DW, mqh.val, avalue,
+ IMA);
+ if (gru_wait(cb) != CBS_IDLE)
+ goto cberr;
+
+ /* If not successfully in swapping queue head, clear the hstatus lock */
+ if (gru_get_amo_value(cb) != avalue) {
+ STAT(mesq_qf_switch_head_failed);
+ gru_gamir(cb, EOP_IR_INC, HSTATUS(mqd->mq_gpa, half), XTYPE_DW,
+ IMA);
+ if (gru_wait(cb) != CBS_IDLE)
+ goto cberr;
+ }
+ return MQIE_AGAIN;
+cberr:
+ STAT(mesq_qf_unexpected_error);
+ return MQE_UNEXPECTED_CB_ERR;
+}
+
+/*
+ * Handle a PUT failure. Note: if message was a 2-line message, one of the
+ * lines might have successfully have been written. Before sending the
+ * message, "present" must be cleared in BOTH lines to prevent the receiver
+ * from prematurely seeing the full message.
+ */
+static int send_message_put_nacked(void *cb, struct gru_message_queue_desc *mqd,
+ void *mesg, int lines)
+{
+ unsigned long m;
+ int ret, loops = 200; /* experimentally determined */
+
+ m = mqd->mq_gpa + (gru_get_amo_value_head(cb) << 6);
+ if (lines == 2) {
+ gru_vset(cb, m, 0, XTYPE_CL, lines, 1, IMA);
+ if (gru_wait(cb) != CBS_IDLE)
+ return MQE_UNEXPECTED_CB_ERR;
+ }
+ gru_vstore(cb, m, gru_get_tri(mesg), XTYPE_CL, lines, 1, IMA);
+ if (gru_wait(cb) != CBS_IDLE)
+ return MQE_UNEXPECTED_CB_ERR;
+
+ if (!mqd->interrupt_vector)
+ return MQE_OK;
+
+ /*
+ * Send a noop message in order to deliver a cross-partition interrupt
+ * to the SSI that contains the target message queue. Normally, the
+ * interrupt is automatically delivered by hardware following mesq
+ * operations, but some error conditions require explicit delivery.
+ * The noop message will trigger delivery. Otherwise partition failures
+ * could cause unrecovered errors.
+ */
+ do {
+ ret = send_noop_message(cb, mqd, mesg);
+ } while ((ret == MQIE_AGAIN || ret == MQE_CONGESTION) && (loops-- > 0));
+
+ if (ret == MQIE_AGAIN || ret == MQE_CONGESTION) {
+ /*
+ * Don't indicate to the app to resend the message, as it's
+ * already been successfully sent. We simply send an OK
+ * (rather than fail the send with MQE_UNEXPECTED_CB_ERR),
+ * assuming that the other side is receiving enough
+ * interrupts to get this message processed anyway.
+ */
+ ret = MQE_OK;
+ }
+ return ret;
+}
+
+/*
+ * Handle a gru_mesq failure. Some of these failures are software recoverable
+ * or retryable.
+ */
+static int send_message_failure(void *cb, struct gru_message_queue_desc *mqd,
+ void *mesg, int lines)
+{
+ int substatus, ret = 0;
+
+ substatus = gru_get_cb_message_queue_substatus(cb);
+ switch (substatus) {
+ case CBSS_NO_ERROR:
+ STAT(mesq_send_unexpected_error);
+ ret = MQE_UNEXPECTED_CB_ERR;
+ break;
+ case CBSS_LB_OVERFLOWED:
+ STAT(mesq_send_lb_overflow);
+ ret = MQE_CONGESTION;
+ break;
+ case CBSS_QLIMIT_REACHED:
+ STAT(mesq_send_qlimit_reached);
+ ret = send_message_queue_full(cb, mqd, mesg, lines);
+ break;
+ case CBSS_AMO_NACKED:
+ STAT(mesq_send_amo_nacked);
+ ret = MQE_CONGESTION;
+ break;
+ case CBSS_PUT_NACKED:
+ STAT(mesq_send_put_nacked);
+ ret = send_message_put_nacked(cb, mqd, mesg, lines);
+ break;
+ case CBSS_PAGE_OVERFLOW:
+ STAT(mesq_page_overflow);
+ fallthrough;
+ default:
+ BUG();
+ }
+ return ret;
+}
+
+/*
+ * Send a message to a message queue
+ * mqd message queue descriptor
+ * mesg message. ust be vaddr within a GSEG
+ * bytes message size (<= 2 CL)
+ */
+int gru_send_message_gpa(struct gru_message_queue_desc *mqd, void *mesg,
+ unsigned int bytes)
+{
+ struct message_header *mhdr;
+ void *cb;
+ void *dsr;
+ int istatus, clines, ret;
+
+ STAT(mesq_send);
+ BUG_ON(bytes < sizeof(int) || bytes > 2 * GRU_CACHE_LINE_BYTES);
+
+ clines = DIV_ROUND_UP(bytes, GRU_CACHE_LINE_BYTES);
+ if (gru_get_cpu_resources(bytes, &cb, &dsr))
+ return MQE_BUG_NO_RESOURCES;
+ memcpy(dsr, mesg, bytes);
+ mhdr = dsr;
+ mhdr->present = MQS_FULL;
+ mhdr->lines = clines;
+ if (clines == 2) {
+ mhdr->present2 = get_present2(mhdr);
+ restore_present2(mhdr, MQS_FULL);
+ }
+
+ do {
+ ret = MQE_OK;
+ gru_mesq(cb, mqd->mq_gpa, gru_get_tri(mhdr), clines, IMA);
+ istatus = gru_wait(cb);
+ if (istatus != CBS_IDLE)
+ ret = send_message_failure(cb, mqd, dsr, clines);
+ } while (ret == MQIE_AGAIN);
+ gru_free_cpu_resources(cb, dsr);
+
+ if (ret)
+ STAT(mesq_send_failed);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(gru_send_message_gpa);
+
+/*
+ * Advance the receive pointer for the queue to the next message.
+ */
+void gru_free_message(struct gru_message_queue_desc *mqd, void *mesg)
+{
+ struct message_queue *mq = mqd->mq;
+ struct message_header *mhdr = mq->next;
+ void *next, *pnext;
+ int half = -1;
+ int lines = mhdr->lines;
+
+ if (lines == 2)
+ restore_present2(mhdr, MQS_EMPTY);
+ mhdr->present = MQS_EMPTY;
+
+ pnext = mq->next;
+ next = pnext + GRU_CACHE_LINE_BYTES * lines;
+ if (next == mq->limit) {
+ next = mq->start;
+ half = 1;
+ } else if (pnext < mq->start2 && next >= mq->start2) {
+ half = 0;
+ }
+
+ if (half >= 0)
+ mq->hstatus[half] = 1;
+ mq->next = next;
+}
+EXPORT_SYMBOL_GPL(gru_free_message);
+
+/*
+ * Get next message from message queue. Return NULL if no message
+ * present. User must call next_message() to move to next message.
+ * rmq message queue
+ */
+void *gru_get_next_message(struct gru_message_queue_desc *mqd)
+{
+ struct message_queue *mq = mqd->mq;
+ struct message_header *mhdr = mq->next;
+ int present = mhdr->present;
+
+ /* skip NOOP messages */
+ while (present == MQS_NOOP) {
+ gru_free_message(mqd, mhdr);
+ mhdr = mq->next;
+ present = mhdr->present;
+ }
+
+ /* Wait for both halves of 2 line messages */
+ if (present == MQS_FULL && mhdr->lines == 2 &&
+ get_present2(mhdr) == MQS_EMPTY)
+ present = MQS_EMPTY;
+
+ if (!present) {
+ STAT(mesq_receive_none);
+ return NULL;
+ }
+
+ if (mhdr->lines == 2)
+ restore_present2(mhdr, mhdr->present2);
+
+ STAT(mesq_receive);
+ return mhdr;
+}
+EXPORT_SYMBOL_GPL(gru_get_next_message);
+
+/* ---------------------- GRU DATA COPY FUNCTIONS ---------------------------*/
+
+/*
+ * Load a DW from a global GPA. The GPA can be a memory or MMR address.
+ */
+int gru_read_gpa(unsigned long *value, unsigned long gpa)
+{
+ void *cb;
+ void *dsr;
+ int ret, iaa;
+
+ STAT(read_gpa);
+ if (gru_get_cpu_resources(GRU_NUM_KERNEL_DSR_BYTES, &cb, &dsr))
+ return MQE_BUG_NO_RESOURCES;
+ iaa = gpa >> 62;
+ gru_vload_phys(cb, gpa, gru_get_tri(dsr), iaa, IMA);
+ ret = gru_wait(cb);
+ if (ret == CBS_IDLE)
+ *value = *(unsigned long *)dsr;
+ gru_free_cpu_resources(cb, dsr);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(gru_read_gpa);
+
+
+/*
+ * Copy a block of data using the GRU resources
+ */
+int gru_copy_gpa(unsigned long dest_gpa, unsigned long src_gpa,
+ unsigned int bytes)
+{
+ void *cb;
+ void *dsr;
+ int ret;
+
+ STAT(copy_gpa);
+ if (gru_get_cpu_resources(GRU_NUM_KERNEL_DSR_BYTES, &cb, &dsr))
+ return MQE_BUG_NO_RESOURCES;
+ gru_bcopy(cb, src_gpa, dest_gpa, gru_get_tri(dsr),
+ XTYPE_B, bytes, GRU_NUM_KERNEL_DSR_CL, IMA);
+ ret = gru_wait(cb);
+ gru_free_cpu_resources(cb, dsr);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(gru_copy_gpa);
+
+/* ------------------- KERNEL QUICKTESTS RUN AT STARTUP ----------------*/
+/* Temp - will delete after we gain confidence in the GRU */
+
+static int quicktest0(unsigned long arg)
+{
+ unsigned long word0;
+ unsigned long word1;
+ void *cb;
+ void *dsr;
+ unsigned long *p;
+ int ret = -EIO;
+
+ if (gru_get_cpu_resources(GRU_CACHE_LINE_BYTES, &cb, &dsr))
+ return MQE_BUG_NO_RESOURCES;
+ p = dsr;
+ word0 = MAGIC;
+ word1 = 0;
+
+ gru_vload(cb, uv_gpa(&word0), gru_get_tri(dsr), XTYPE_DW, 1, 1, IMA);
+ if (gru_wait(cb) != CBS_IDLE) {
+ printk(KERN_DEBUG "GRU:%d quicktest0: CBR failure 1\n", smp_processor_id());
+ goto done;
+ }
+
+ if (*p != MAGIC) {
+ printk(KERN_DEBUG "GRU:%d quicktest0 bad magic 0x%lx\n", smp_processor_id(), *p);
+ goto done;
+ }
+ gru_vstore(cb, uv_gpa(&word1), gru_get_tri(dsr), XTYPE_DW, 1, 1, IMA);
+ if (gru_wait(cb) != CBS_IDLE) {
+ printk(KERN_DEBUG "GRU:%d quicktest0: CBR failure 2\n", smp_processor_id());
+ goto done;
+ }
+
+ if (word0 != word1 || word1 != MAGIC) {
+ printk(KERN_DEBUG
+ "GRU:%d quicktest0 err: found 0x%lx, expected 0x%lx\n",
+ smp_processor_id(), word1, MAGIC);
+ goto done;
+ }
+ ret = 0;
+
+done:
+ gru_free_cpu_resources(cb, dsr);
+ return ret;
+}
+
+#define ALIGNUP(p, q) ((void *)(((unsigned long)(p) + (q) - 1) & ~(q - 1)))
+
+static int quicktest1(unsigned long arg)
+{
+ struct gru_message_queue_desc mqd;
+ void *p, *mq;
+ int i, ret = -EIO;
+ char mes[GRU_CACHE_LINE_BYTES], *m;
+
+ /* Need 1K cacheline aligned that does not cross page boundary */
+ p = kmalloc(4096, 0);
+ if (p == NULL)
+ return -ENOMEM;
+ mq = ALIGNUP(p, 1024);
+ memset(mes, 0xee, sizeof(mes));
+
+ gru_create_message_queue(&mqd, mq, 8 * GRU_CACHE_LINE_BYTES, 0, 0, 0);
+ for (i = 0; i < 6; i++) {
+ mes[8] = i;
+ do {
+ ret = gru_send_message_gpa(&mqd, mes, sizeof(mes));
+ } while (ret == MQE_CONGESTION);
+ if (ret)
+ break;
+ }
+ if (ret != MQE_QUEUE_FULL || i != 4) {
+ printk(KERN_DEBUG "GRU:%d quicktest1: unexpected status %d, i %d\n",
+ smp_processor_id(), ret, i);
+ goto done;
+ }
+
+ for (i = 0; i < 6; i++) {
+ m = gru_get_next_message(&mqd);
+ if (!m || m[8] != i)
+ break;
+ gru_free_message(&mqd, m);
+ }
+ if (i != 4) {
+ printk(KERN_DEBUG "GRU:%d quicktest2: bad message, i %d, m %p, m8 %d\n",
+ smp_processor_id(), i, m, m ? m[8] : -1);
+ goto done;
+ }
+ ret = 0;
+
+done:
+ kfree(p);
+ return ret;
+}
+
+static int quicktest2(unsigned long arg)
+{
+ static DECLARE_COMPLETION(cmp);
+ unsigned long han;
+ int blade_id = 0;
+ int numcb = 4;
+ int ret = 0;
+ unsigned long *buf;
+ void *cb0, *cb;
+ struct gru_control_block_status *gen;
+ int i, k, istatus, bytes;
+
+ bytes = numcb * 4 * 8;
+ buf = kmalloc(bytes, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ ret = -EBUSY;
+ han = gru_reserve_async_resources(blade_id, numcb, 0, &cmp);
+ if (!han)
+ goto done;
+
+ gru_lock_async_resource(han, &cb0, NULL);
+ memset(buf, 0xee, bytes);
+ for (i = 0; i < numcb; i++)
+ gru_vset(cb0 + i * GRU_HANDLE_STRIDE, uv_gpa(&buf[i * 4]), 0,
+ XTYPE_DW, 4, 1, IMA_INTERRUPT);
+
+ ret = 0;
+ k = numcb;
+ do {
+ gru_wait_async_cbr(han);
+ for (i = 0; i < numcb; i++) {
+ cb = cb0 + i * GRU_HANDLE_STRIDE;
+ istatus = gru_check_status(cb);
+ if (istatus != CBS_ACTIVE && istatus != CBS_CALL_OS)
+ break;
+ }
+ if (i == numcb)
+ continue;
+ if (istatus != CBS_IDLE) {
+ printk(KERN_DEBUG "GRU:%d quicktest2: cb %d, exception\n", smp_processor_id(), i);
+ ret = -EFAULT;
+ } else if (buf[4 * i] || buf[4 * i + 1] || buf[4 * i + 2] ||
+ buf[4 * i + 3]) {
+ printk(KERN_DEBUG "GRU:%d quicktest2:cb %d, buf 0x%lx, 0x%lx, 0x%lx, 0x%lx\n",
+ smp_processor_id(), i, buf[4 * i], buf[4 * i + 1], buf[4 * i + 2], buf[4 * i + 3]);
+ ret = -EIO;
+ }
+ k--;
+ gen = cb;
+ gen->istatus = CBS_CALL_OS; /* don't handle this CBR again */
+ } while (k);
+ BUG_ON(cmp.done);
+
+ gru_unlock_async_resource(han);
+ gru_release_async_resources(han);
+done:
+ kfree(buf);
+ return ret;
+}
+
+#define BUFSIZE 200
+static int quicktest3(unsigned long arg)
+{
+ char buf1[BUFSIZE], buf2[BUFSIZE];
+ int ret = 0;
+
+ memset(buf2, 0, sizeof(buf2));
+ memset(buf1, get_cycles() & 255, sizeof(buf1));
+ gru_copy_gpa(uv_gpa(buf2), uv_gpa(buf1), BUFSIZE);
+ if (memcmp(buf1, buf2, BUFSIZE)) {
+ printk(KERN_DEBUG "GRU:%d quicktest3 error\n", smp_processor_id());
+ ret = -EIO;
+ }
+ return ret;
+}
+
+/*
+ * Debugging only. User hook for various kernel tests
+ * of driver & gru.
+ */
+int gru_ktest(unsigned long arg)
+{
+ int ret = -EINVAL;
+
+ switch (arg & 0xff) {
+ case 0:
+ ret = quicktest0(arg);
+ break;
+ case 1:
+ ret = quicktest1(arg);
+ break;
+ case 2:
+ ret = quicktest2(arg);
+ break;
+ case 3:
+ ret = quicktest3(arg);
+ break;
+ case 99:
+ ret = gru_free_kernel_contexts();
+ break;
+ }
+ return ret;
+
+}
+
+int gru_kservices_init(void)
+{
+ return 0;
+}
+
+void gru_kservices_exit(void)
+{
+ if (gru_free_kernel_contexts())
+ BUG();
+}
+