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android-kvm / linux / 2280740f01aee0883a2885f332aee27449390a4b / . / drivers / infiniband / hw / hfi1 / pio.c
blob: ed72b5aca1396290b6ccb4b1d50d3b23dd55b1d8 [file] [log] [blame]
/*
* Copyright(c) 2015-2017 Intel Corporation.
*
* This file is provided under a dual BSD/GPLv2 license. When using or
* redistributing this file, you may do so under either license.
*
* GPL LICENSE SUMMARY
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* BSD LICENSE
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* - Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <linux/delay.h>
#include "hfi.h"
#include "qp.h"
#include "trace.h"
#define SC_CTXT_PACKET_EGRESS_TIMEOUT 350 /* in chip cycles */
#define SC(name) SEND_CTXT_##name
/*
* Send Context functions
*/
static void sc_wait_for_packet_egress(struct send_context *sc, int pause);
/*
* Set the CM reset bit and wait for it to clear. Use the provided
* sendctrl register. This routine has no locking.
*/
void __cm_reset(struct hfi1_devdata *dd, u64 sendctrl)
{
write_csr(dd, SEND_CTRL, sendctrl | SEND_CTRL_CM_RESET_SMASK);
while (1) {
udelay(1);
sendctrl = read_csr(dd, SEND_CTRL);
if ((sendctrl & SEND_CTRL_CM_RESET_SMASK) == 0)
break;
}
}
/* defined in header release 48 and higher */
#ifndef SEND_CTRL_UNSUPPORTED_VL_SHIFT
#define SEND_CTRL_UNSUPPORTED_VL_SHIFT 3
#define SEND_CTRL_UNSUPPORTED_VL_MASK 0xffull
#define SEND_CTRL_UNSUPPORTED_VL_SMASK (SEND_CTRL_UNSUPPORTED_VL_MASK \
<< SEND_CTRL_UNSUPPORTED_VL_SHIFT)
#endif
/* global control of PIO send */
void pio_send_control(struct hfi1_devdata *dd, int op)
{
u64 reg, mask;
unsigned long flags;
int write = 1; /* write sendctrl back */
int flush = 0; /* re-read sendctrl to make sure it is flushed */
spin_lock_irqsave(&dd->sendctrl_lock, flags);
reg = read_csr(dd, SEND_CTRL);
switch (op) {
case PSC_GLOBAL_ENABLE:
reg |= SEND_CTRL_SEND_ENABLE_SMASK;
/* Fall through */
case PSC_DATA_VL_ENABLE:
/* Disallow sending on VLs not enabled */
mask = (((~0ull) << num_vls) & SEND_CTRL_UNSUPPORTED_VL_MASK) <<
SEND_CTRL_UNSUPPORTED_VL_SHIFT;
reg = (reg & ~SEND_CTRL_UNSUPPORTED_VL_SMASK) | mask;
break;
case PSC_GLOBAL_DISABLE:
reg &= ~SEND_CTRL_SEND_ENABLE_SMASK;
break;
case PSC_GLOBAL_VLARB_ENABLE:
reg |= SEND_CTRL_VL_ARBITER_ENABLE_SMASK;
break;
case PSC_GLOBAL_VLARB_DISABLE:
reg &= ~SEND_CTRL_VL_ARBITER_ENABLE_SMASK;
break;
case PSC_CM_RESET:
__cm_reset(dd, reg);
write = 0; /* CSR already written (and flushed) */
break;
case PSC_DATA_VL_DISABLE:
reg |= SEND_CTRL_UNSUPPORTED_VL_SMASK;
flush = 1;
break;
default:
dd_dev_err(dd, "%s: invalid control %d\n", __func__, op);
break;
}
if (write) {
write_csr(dd, SEND_CTRL, reg);
if (flush)
(void)read_csr(dd, SEND_CTRL); /* flush write */
}
spin_unlock_irqrestore(&dd->sendctrl_lock, flags);
}
/* number of send context memory pools */
#define NUM_SC_POOLS 2
/* Send Context Size (SCS) wildcards */
#define SCS_POOL_0 -1
#define SCS_POOL_1 -2
/* Send Context Count (SCC) wildcards */
#define SCC_PER_VL -1
#define SCC_PER_CPU -2
#define SCC_PER_KRCVQ -3
/* Send Context Size (SCS) constants */
#define SCS_ACK_CREDITS 32
#define SCS_VL15_CREDITS 102 /* 3 pkts of 2048B data + 128B header */
#define PIO_THRESHOLD_CEILING 4096
#define PIO_WAIT_BATCH_SIZE 5
/* default send context sizes */
static struct sc_config_sizes sc_config_sizes[SC_MAX] = {
[SC_KERNEL] = { .size = SCS_POOL_0, /* even divide, pool 0 */
.count = SCC_PER_VL }, /* one per NUMA */
[SC_ACK] = { .size = SCS_ACK_CREDITS,
.count = SCC_PER_KRCVQ },
[SC_USER] = { .size = SCS_POOL_0, /* even divide, pool 0 */
.count = SCC_PER_CPU }, /* one per CPU */
[SC_VL15] = { .size = SCS_VL15_CREDITS,
.count = 1 },
};
/* send context memory pool configuration */
struct mem_pool_config {
int centipercent; /* % of memory, in 100ths of 1% */
int absolute_blocks; /* absolute block count */
};
/* default memory pool configuration: 100% in pool 0 */
static struct mem_pool_config sc_mem_pool_config[NUM_SC_POOLS] = {
/* centi%, abs blocks */
{ 10000, -1 }, /* pool 0 */
{ 0, -1 }, /* pool 1 */
};
/* memory pool information, used when calculating final sizes */
struct mem_pool_info {
int centipercent; /*
* 100th of 1% of memory to use, -1 if blocks
* already set
*/
int count; /* count of contexts in the pool */
int blocks; /* block size of the pool */
int size; /* context size, in blocks */
};
/*
* Convert a pool wildcard to a valid pool index. The wildcards
* start at -1 and increase negatively. Map them as:
* -1 => 0
* -2 => 1
* etc.
*
* Return -1 on non-wildcard input, otherwise convert to a pool number.
*/
static int wildcard_to_pool(int wc)
{
if (wc >= 0)
return -1; /* non-wildcard */
return -wc - 1;
}
static const char *sc_type_names[SC_MAX] = {
"kernel",
"ack",
"user",
"vl15"
};
static const char *sc_type_name(int index)
{
if (index < 0 || index >= SC_MAX)
return "unknown";
return sc_type_names[index];
}
/*
* Read the send context memory pool configuration and send context
* size configuration. Replace any wildcards and come up with final
* counts and sizes for the send context types.
*/
int init_sc_pools_and_sizes(struct hfi1_devdata *dd)
{
struct mem_pool_info mem_pool_info[NUM_SC_POOLS] = { { 0 } };
int total_blocks = (dd->chip_pio_mem_size / PIO_BLOCK_SIZE) - 1;
int total_contexts = 0;
int fixed_blocks;
int pool_blocks;
int used_blocks;
int cp_total; /* centipercent total */
int ab_total; /* absolute block total */
int extra;
int i;
/*
* When SDMA is enabled, kernel context pio packet size is capped by
* "piothreshold". Reduce pio buffer allocation for kernel context by
* setting it to a fixed size. The allocation allows 3-deep buffering
* of the largest pio packets plus up to 128 bytes header, sufficient
* to maintain verbs performance.
*
* When SDMA is disabled, keep the default pooling allocation.
*/
if (HFI1_CAP_IS_KSET(SDMA)) {
u16 max_pkt_size = (piothreshold < PIO_THRESHOLD_CEILING) ?
piothreshold : PIO_THRESHOLD_CEILING;
sc_config_sizes[SC_KERNEL].size =
3 * (max_pkt_size + 128) / PIO_BLOCK_SIZE;
}
/*
* Step 0:
* - copy the centipercents/absolute sizes from the pool config
* - sanity check these values
* - add up centipercents, then later check for full value
* - add up absolute blocks, then later check for over-commit
*/
cp_total = 0;
ab_total = 0;
for (i = 0; i < NUM_SC_POOLS; i++) {
int cp = sc_mem_pool_config[i].centipercent;
int ab = sc_mem_pool_config[i].absolute_blocks;
/*
* A negative value is "unused" or "invalid". Both *can*
* be valid, but centipercent wins, so check that first
*/
if (cp >= 0) { /* centipercent valid */
cp_total += cp;
} else if (ab >= 0) { /* absolute blocks valid */
ab_total += ab;
} else { /* neither valid */
dd_dev_err(
dd,
"Send context memory pool %d: both the block count and centipercent are invalid\n",
i);
return -EINVAL;
}
mem_pool_info[i].centipercent = cp;
mem_pool_info[i].blocks = ab;
}
/* do not use both % and absolute blocks for different pools */
if (cp_total != 0 && ab_total != 0) {
dd_dev_err(
dd,
"All send context memory pools must be described as either centipercent or blocks, no mixing between pools\n");
return -EINVAL;
}
/* if any percentages are present, they must add up to 100% x 100 */
if (cp_total != 0 && cp_total != 10000) {
dd_dev_err(
dd,
"Send context memory pool centipercent is %d, expecting 10000\n",
cp_total);
return -EINVAL;
}
/* the absolute pool total cannot be more than the mem total */
if (ab_total > total_blocks) {
dd_dev_err(
dd,
"Send context memory pool absolute block count %d is larger than the memory size %d\n",
ab_total, total_blocks);
return -EINVAL;
}
/*
* Step 2:
* - copy from the context size config
* - replace context type wildcard counts with real values
* - add up non-memory pool block sizes
* - add up memory pool user counts
*/
fixed_blocks = 0;
for (i = 0; i < SC_MAX; i++) {
int count = sc_config_sizes[i].count;
int size = sc_config_sizes[i].size;
int pool;
/*
* Sanity check count: Either a positive value or
* one of the expected wildcards is valid. The positive
* value is checked later when we compare against total
* memory available.
*/
if (i == SC_ACK) {
count = dd->n_krcv_queues;
} else if (i == SC_KERNEL) {
count = INIT_SC_PER_VL * num_vls;
} else if (count == SCC_PER_CPU) {
count = dd->num_rcv_contexts - dd->n_krcv_queues;
} else if (count < 0) {
dd_dev_err(
dd,
"%s send context invalid count wildcard %d\n",
sc_type_name(i), count);
return -EINVAL;
}
if (total_contexts + count > dd->chip_send_contexts)
count = dd->chip_send_contexts - total_contexts;
total_contexts += count;
/*
* Sanity check pool: The conversion will return a pool
* number or -1 if a fixed (non-negative) value. The fixed
* value is checked later when we compare against
* total memory available.
*/
pool = wildcard_to_pool(size);
if (pool == -1) { /* non-wildcard */
fixed_blocks += size * count;
} else if (pool < NUM_SC_POOLS) { /* valid wildcard */
mem_pool_info[pool].count += count;
} else { /* invalid wildcard */
dd_dev_err(
dd,
"%s send context invalid pool wildcard %d\n",
sc_type_name(i), size);
return -EINVAL;
}
dd->sc_sizes[i].count = count;
dd->sc_sizes[i].size = size;
}
if (fixed_blocks > total_blocks) {
dd_dev_err(
dd,
"Send context fixed block count, %u, larger than total block count %u\n",
fixed_blocks, total_blocks);
return -EINVAL;
}
/* step 3: calculate the blocks in the pools, and pool context sizes */
pool_blocks = total_blocks - fixed_blocks;
if (ab_total > pool_blocks) {
dd_dev_err(
dd,
"Send context fixed pool sizes, %u, larger than pool block count %u\n",
ab_total, pool_blocks);
return -EINVAL;
}
/* subtract off the fixed pool blocks */
pool_blocks -= ab_total;
for (i = 0; i < NUM_SC_POOLS; i++) {
struct mem_pool_info *pi = &mem_pool_info[i];
/* % beats absolute blocks */
if (pi->centipercent >= 0)
pi->blocks = (pool_blocks * pi->centipercent) / 10000;
if (pi->blocks == 0 && pi->count != 0) {
dd_dev_err(
dd,
"Send context memory pool %d has %u contexts, but no blocks\n",
i, pi->count);
return -EINVAL;
}
if (pi->count == 0) {
/* warn about wasted blocks */
if (pi->blocks != 0)
dd_dev_err(
dd,
"Send context memory pool %d has %u blocks, but zero contexts\n",
i, pi->blocks);
pi->size = 0;
} else {
pi->size = pi->blocks / pi->count;
}
}
/* step 4: fill in the context type sizes from the pool sizes */
used_blocks = 0;
for (i = 0; i < SC_MAX; i++) {
if (dd->sc_sizes[i].size < 0) {
unsigned pool = wildcard_to_pool(dd->sc_sizes[i].size);
WARN_ON_ONCE(pool >= NUM_SC_POOLS);
dd->sc_sizes[i].size = mem_pool_info[pool].size;
}
/* make sure we are not larger than what is allowed by the HW */
#define PIO_MAX_BLOCKS 1024
if (dd->sc_sizes[i].size > PIO_MAX_BLOCKS)
dd->sc_sizes[i].size = PIO_MAX_BLOCKS;
/* calculate our total usage */
used_blocks += dd->sc_sizes[i].size * dd->sc_sizes[i].count;
}
extra = total_blocks - used_blocks;
if (extra != 0)
dd_dev_info(dd, "unused send context blocks: %d\n", extra);
return total_contexts;
}
int init_send_contexts(struct hfi1_devdata *dd)
{
u16 base;
int ret, i, j, context;
ret = init_credit_return(dd);
if (ret)
return ret;
dd->hw_to_sw = kmalloc_array(TXE_NUM_CONTEXTS, sizeof(u8),
GFP_KERNEL);
dd->send_contexts = kcalloc(dd->num_send_contexts,
sizeof(struct send_context_info),
GFP_KERNEL);
if (!dd->send_contexts || !dd->hw_to_sw) {
kfree(dd->hw_to_sw);
kfree(dd->send_contexts);
free_credit_return(dd);
return -ENOMEM;
}
/* hardware context map starts with invalid send context indices */
for (i = 0; i < TXE_NUM_CONTEXTS; i++)
dd->hw_to_sw[i] = INVALID_SCI;
/*
* All send contexts have their credit sizes. Allocate credits
* for each context one after another from the global space.
*/
context = 0;
base = 1;
for (i = 0; i < SC_MAX; i++) {
struct sc_config_sizes *scs = &dd->sc_sizes[i];
for (j = 0; j < scs->count; j++) {
struct send_context_info *sci =
&dd->send_contexts[context];
sci->type = i;
sci->base = base;
sci->credits = scs->size;
context++;
base += scs->size;
}
}
return 0;
}
/*
* Allocate a software index and hardware context of the given type.
*
* Must be called with dd->sc_lock held.
*/
static int sc_hw_alloc(struct hfi1_devdata *dd, int type, u32 *sw_index,
u32 *hw_context)
{
struct send_context_info *sci;
u32 index;
u32 context;
for (index = 0, sci = &dd->send_contexts[0];
index < dd->num_send_contexts; index++, sci++) {
if (sci->type == type && sci->allocated == 0) {
sci->allocated = 1;
/* use a 1:1 mapping, but make them non-equal */
context = dd->chip_send_contexts - index - 1;
dd->hw_to_sw[context] = index;
*sw_index = index;
*hw_context = context;
return 0; /* success */
}
}
dd_dev_err(dd, "Unable to locate a free type %d send context\n", type);
return -ENOSPC;
}
/*
* Free the send context given by its software index.
*
* Must be called with dd->sc_lock held.
*/
static void sc_hw_free(struct hfi1_devdata *dd, u32 sw_index, u32 hw_context)
{
struct send_context_info *sci;
sci = &dd->send_contexts[sw_index];
if (!sci->allocated) {
dd_dev_err(dd, "%s: sw_index %u not allocated? hw_context %u\n",
__func__, sw_index, hw_context);
}
sci->allocated = 0;
dd->hw_to_sw[hw_context] = INVALID_SCI;
}
/* return the base context of a context in a group */
static inline u32 group_context(u32 context, u32 group)
{
return (context >> group) << group;
}
/* return the size of a group */
static inline u32 group_size(u32 group)
{
return 1 << group;
}
/*
* Obtain the credit return addresses, kernel virtual and bus, for the
* given sc.
*
* To understand this routine:
* o va and dma are arrays of struct credit_return. One for each physical
* send context, per NUMA.
* o Each send context always looks in its relative location in a struct
* credit_return for its credit return.
* o Each send context in a group must have its return address CSR programmed
* with the same value. Use the address of the first send context in the
* group.
*/
static void cr_group_addresses(struct send_context *sc, dma_addr_t *dma)
{
u32 gc = group_context(sc->hw_context, sc->group);
u32 index = sc->hw_context & 0x7;
sc->hw_free = &sc->dd->cr_base[sc->node].va[gc].cr[index];
*dma = (unsigned long)
&((struct credit_return *)sc->dd->cr_base[sc->node].dma)[gc];
}
/*
* Work queue function triggered in error interrupt routine for
* kernel contexts.
*/
static void sc_halted(struct work_struct *work)
{
struct send_context *sc;
sc = container_of(work, struct send_context, halt_work);
sc_restart(sc);
}
/*
* Calculate PIO block threshold for this send context using the given MTU.
* Trigger a return when one MTU plus optional header of credits remain.
*
* Parameter mtu is in bytes.
* Parameter hdrqentsize is in DWORDs.
*
* Return value is what to write into the CSR: trigger return when
* unreturned credits pass this count.
*/
u32 sc_mtu_to_threshold(struct send_context *sc, u32 mtu, u32 hdrqentsize)
{
u32 release_credits;
u32 threshold;
/* add in the header size, then divide by the PIO block size */
mtu += hdrqentsize << 2;
release_credits = DIV_ROUND_UP(mtu, PIO_BLOCK_SIZE);
/* check against this context's credits */
if (sc->credits <= release_credits)
threshold = 1;
else
threshold = sc->credits - release_credits;
return threshold;
}
/*
* Calculate credit threshold in terms of percent of the allocated credits.
* Trigger when unreturned credits equal or exceed the percentage of the whole.
*
* Return value is what to write into the CSR: trigger return when
* unreturned credits pass this count.
*/
u32 sc_percent_to_threshold(struct send_context *sc, u32 percent)
{
return (sc->credits * percent) / 100;
}
/*
* Set the credit return threshold.
*/
void sc_set_cr_threshold(struct send_context *sc, u32 new_threshold)
{
unsigned long flags;
u32 old_threshold;
int force_return = 0;
spin_lock_irqsave(&sc->credit_ctrl_lock, flags);
old_threshold = (sc->credit_ctrl >>
SC(CREDIT_CTRL_THRESHOLD_SHIFT))
& SC(CREDIT_CTRL_THRESHOLD_MASK);
if (new_threshold != old_threshold) {
sc->credit_ctrl =
(sc->credit_ctrl
& ~SC(CREDIT_CTRL_THRESHOLD_SMASK))
| ((new_threshold
& SC(CREDIT_CTRL_THRESHOLD_MASK))
<< SC(CREDIT_CTRL_THRESHOLD_SHIFT));
write_kctxt_csr(sc->dd, sc->hw_context,
SC(CREDIT_CTRL), sc->credit_ctrl);
/* force a credit return on change to avoid a possible stall */
force_return = 1;
}
spin_unlock_irqrestore(&sc->credit_ctrl_lock, flags);
if (force_return)
sc_return_credits(sc);
}
/*
* set_pio_integrity
*
* Set the CHECK_ENABLE register for the send context 'sc'.
*/
void set_pio_integrity(struct send_context *sc)
{
struct hfi1_devdata *dd = sc->dd;
u32 hw_context = sc->hw_context;
int type = sc->type;
write_kctxt_csr(dd, hw_context,
SC(CHECK_ENABLE),
hfi1_pkt_default_send_ctxt_mask(dd, type));
}
static u32 get_buffers_allocated(struct send_context *sc)
{
int cpu;
u32 ret = 0;
for_each_possible_cpu(cpu)
ret += *per_cpu_ptr(sc->buffers_allocated, cpu);
return ret;
}
static void reset_buffers_allocated(struct send_context *sc)
{
int cpu;
for_each_possible_cpu(cpu)
(*per_cpu_ptr(sc->buffers_allocated, cpu)) = 0;
}
/*
* Allocate a NUMA relative send context structure of the given type along
* with a HW context.
*/
struct send_context *sc_alloc(struct hfi1_devdata *dd, int type,
uint hdrqentsize, int numa)
{
struct send_context_info *sci;
struct send_context *sc = NULL;
int req_type = type;
dma_addr_t dma;
unsigned long flags;
u64 reg;
u32 thresh;
u32 sw_index;
u32 hw_context;
int ret;
u8 opval, opmask;
/* do not allocate while frozen */
if (dd->flags & HFI1_FROZEN)
return NULL;
sc = kzalloc_node(sizeof(*sc), GFP_KERNEL, numa);
if (!sc)
return NULL;
sc->buffers_allocated = alloc_percpu(u32);
if (!sc->buffers_allocated) {
kfree(sc);
dd_dev_err(dd,
"Cannot allocate buffers_allocated per cpu counters\n"
);
return NULL;
}
/*
* VNIC contexts are dynamically allocated.
* Hence, pick a user context for VNIC.
*/
if (type == SC_VNIC)
type = SC_USER;
spin_lock_irqsave(&dd->sc_lock, flags);
ret = sc_hw_alloc(dd, type, &sw_index, &hw_context);
if (ret) {
spin_unlock_irqrestore(&dd->sc_lock, flags);
free_percpu(sc->buffers_allocated);
kfree(sc);
return NULL;
}
/*
* VNIC contexts are used by kernel driver.
* Hence, mark them as kernel contexts.
*/
if (req_type == SC_VNIC) {
dd->send_contexts[sw_index].type = SC_KERNEL;
type = SC_KERNEL;
}
sci = &dd->send_contexts[sw_index];
sci->sc = sc;
sc->dd = dd;
sc->node = numa;
sc->type = type;
spin_lock_init(&sc->alloc_lock);
spin_lock_init(&sc->release_lock);
spin_lock_init(&sc->credit_ctrl_lock);
INIT_LIST_HEAD(&sc->piowait);
INIT_WORK(&sc->halt_work, sc_halted);
init_waitqueue_head(&sc->halt_wait);
/* grouping is always single context for now */
sc->group = 0;
sc->sw_index = sw_index;
sc->hw_context = hw_context;
cr_group_addresses(sc, &dma);
sc->credits = sci->credits;
sc->size = sc->credits * PIO_BLOCK_SIZE;
/* PIO Send Memory Address details */
#define PIO_ADDR_CONTEXT_MASK 0xfful
#define PIO_ADDR_CONTEXT_SHIFT 16
sc->base_addr = dd->piobase + ((hw_context & PIO_ADDR_CONTEXT_MASK)
<< PIO_ADDR_CONTEXT_SHIFT);
/* set base and credits */
reg = ((sci->credits & SC(CTRL_CTXT_DEPTH_MASK))
<< SC(CTRL_CTXT_DEPTH_SHIFT))
| ((sci->base & SC(CTRL_CTXT_BASE_MASK))
<< SC(CTRL_CTXT_BASE_SHIFT));
write_kctxt_csr(dd, hw_context, SC(CTRL), reg);
set_pio_integrity(sc);
/* unmask all errors */
write_kctxt_csr(dd, hw_context, SC(ERR_MASK), (u64)-1);
/* set the default partition key */
write_kctxt_csr(dd, hw_context, SC(CHECK_PARTITION_KEY),
(SC(CHECK_PARTITION_KEY_VALUE_MASK) &
DEFAULT_PKEY) <<
SC(CHECK_PARTITION_KEY_VALUE_SHIFT));
/* per context type checks */
if (type == SC_USER) {
opval = USER_OPCODE_CHECK_VAL;
opmask = USER_OPCODE_CHECK_MASK;
} else {
opval = OPCODE_CHECK_VAL_DISABLED;
opmask = OPCODE_CHECK_MASK_DISABLED;
}
/* set the send context check opcode mask and value */
write_kctxt_csr(dd, hw_context, SC(CHECK_OPCODE),
((u64)opmask << SC(CHECK_OPCODE_MASK_SHIFT)) |
((u64)opval << SC(CHECK_OPCODE_VALUE_SHIFT)));
/* set up credit return */
reg = dma & SC(CREDIT_RETURN_ADDR_ADDRESS_SMASK);
write_kctxt_csr(dd, hw_context, SC(CREDIT_RETURN_ADDR), reg);
/*
* Calculate the initial credit return threshold.
*
* For Ack contexts, set a threshold for half the credits.
* For User contexts use the given percentage. This has been
* sanitized on driver start-up.
* For Kernel contexts, use the default MTU plus a header
* or half the credits, whichever is smaller. This should
* work for both the 3-deep buffering allocation and the
* pooling allocation.
*/
if (type == SC_ACK) {
thresh = sc_percent_to_threshold(sc, 50);
} else if (type == SC_USER) {
thresh = sc_percent_to_threshold(sc,
user_credit_return_threshold);
} else { /* kernel */
thresh = min(sc_percent_to_threshold(sc, 50),
sc_mtu_to_threshold(sc, hfi1_max_mtu,
hdrqentsize));
}
reg = thresh << SC(CREDIT_CTRL_THRESHOLD_SHIFT);
/* add in early return */
if (type == SC_USER && HFI1_CAP_IS_USET(EARLY_CREDIT_RETURN))
reg |= SC(CREDIT_CTRL_EARLY_RETURN_SMASK);
else if (HFI1_CAP_IS_KSET(EARLY_CREDIT_RETURN)) /* kernel, ack */
reg |= SC(CREDIT_CTRL_EARLY_RETURN_SMASK);
/* set up write-through credit_ctrl */
sc->credit_ctrl = reg;
write_kctxt_csr(dd, hw_context, SC(CREDIT_CTRL), reg);
/* User send contexts should not allow sending on VL15 */
if (type == SC_USER) {
reg = 1ULL << 15;
write_kctxt_csr(dd, hw_context, SC(CHECK_VL), reg);
}
spin_unlock_irqrestore(&dd->sc_lock, flags);
/*
* Allocate shadow ring to track outstanding PIO buffers _after_
* unlocking. We don't know the size until the lock is held and
* we can't allocate while the lock is held. No one is using
* the context yet, so allocate it now.
*
* User contexts do not get a shadow ring.
*/
if (type != SC_USER) {
/*
* Size the shadow ring 1 larger than the number of credits
* so head == tail can mean empty.
*/
sc->sr_size = sci->credits + 1;
sc->sr = kzalloc_node(sizeof(union pio_shadow_ring) *
sc->sr_size, GFP_KERNEL, numa);
if (!sc->sr) {
sc_free(sc);
return NULL;
}
}
hfi1_cdbg(PIO,
"Send context %u(%u) %s group %u credits %u credit_ctrl 0x%llx threshold %u\n",
sw_index,
hw_context,
sc_type_name(type),
sc->group,
sc->credits,
sc->credit_ctrl,
thresh);
return sc;
}
/* free a per-NUMA send context structure */
void sc_free(struct send_context *sc)
{
struct hfi1_devdata *dd;
unsigned long flags;
u32 sw_index;
u32 hw_context;
if (!sc)
return;
sc->flags |= SCF_IN_FREE; /* ensure no restarts */
dd = sc->dd;
if (!list_empty(&sc->piowait))
dd_dev_err(dd, "piowait list not empty!\n");
sw_index = sc->sw_index;
hw_context = sc->hw_context;
sc_disable(sc); /* make sure the HW is disabled */
flush_work(&sc->halt_work);
spin_lock_irqsave(&dd->sc_lock, flags);
dd->send_contexts[sw_index].sc = NULL;
/* clear/disable all registers set in sc_alloc */
write_kctxt_csr(dd, hw_context, SC(CTRL), 0);
write_kctxt_csr(dd, hw_context, SC(CHECK_ENABLE), 0);
write_kctxt_csr(dd, hw_context, SC(ERR_MASK), 0);
write_kctxt_csr(dd, hw_context, SC(CHECK_PARTITION_KEY), 0);
write_kctxt_csr(dd, hw_context, SC(CHECK_OPCODE), 0);
write_kctxt_csr(dd, hw_context, SC(CREDIT_RETURN_ADDR), 0);
write_kctxt_csr(dd, hw_context, SC(CREDIT_CTRL), 0);
/* release the index and context for re-use */
sc_hw_free(dd, sw_index, hw_context);
spin_unlock_irqrestore(&dd->sc_lock, flags);
kfree(sc->sr);
free_percpu(sc->buffers_allocated);
kfree(sc);
}
/* disable the context */
void sc_disable(struct send_context *sc)
{
u64 reg;
unsigned long flags;
struct pio_buf *pbuf;
if (!sc)
return;
/* do all steps, even if already disabled */
spin_lock_irqsave(&sc->alloc_lock, flags);
reg = read_kctxt_csr(sc->dd, sc->hw_context, SC(CTRL));
reg &= ~SC(CTRL_CTXT_ENABLE_SMASK);
sc->flags &= ~SCF_ENABLED;
sc_wait_for_packet_egress(sc, 1);
write_kctxt_csr(sc->dd, sc->hw_context, SC(CTRL), reg);
spin_unlock_irqrestore(&sc->alloc_lock, flags);
/*
* Flush any waiters. Once the context is disabled,
* credit return interrupts are stopped (although there
* could be one in-process when the context is disabled).
* Wait one microsecond for any lingering interrupts, then
* proceed with the flush.
*/
udelay(1);
spin_lock_irqsave(&sc->release_lock, flags);
if (sc->sr) { /* this context has a shadow ring */
while (sc->sr_tail != sc->sr_head) {
pbuf = &sc->sr[sc->sr_tail].pbuf;
if (pbuf->cb)
(*pbuf->cb)(pbuf->arg, PRC_SC_DISABLE);
sc->sr_tail++;
if (sc->sr_tail >= sc->sr_size)
sc->sr_tail = 0;
}
}
spin_unlock_irqrestore(&sc->release_lock, flags);
}
/* return SendEgressCtxtStatus.PacketOccupancy */
#define packet_occupancy(r) \
(((r) & SEND_EGRESS_CTXT_STATUS_CTXT_EGRESS_PACKET_OCCUPANCY_SMASK)\
>> SEND_EGRESS_CTXT_STATUS_CTXT_EGRESS_PACKET_OCCUPANCY_SHIFT)
/* is egress halted on the context? */
#define egress_halted(r) \
((r) & SEND_EGRESS_CTXT_STATUS_CTXT_EGRESS_HALT_STATUS_SMASK)
/* wait for packet egress, optionally pause for credit return */
static void sc_wait_for_packet_egress(struct send_context *sc, int pause)
{
struct hfi1_devdata *dd = sc->dd;
u64 reg = 0;
u64 reg_prev;
u32 loop = 0;
while (1) {
reg_prev = reg;
reg = read_csr(dd, sc->hw_context * 8 +
SEND_EGRESS_CTXT_STATUS);
/* done if egress is stopped */
if (egress_halted(reg))
break;
reg = packet_occupancy(reg);
if (reg == 0)
break;
/* counter is reset if occupancy count changes */
if (reg != reg_prev)
loop = 0;
if (loop > 50000) {
/* timed out - bounce the link */
dd_dev_err(dd,
"%s: context %u(%u) timeout waiting for packets to egress, remaining count %u, bouncing link\n",
__func__, sc->sw_index,
sc->hw_context, (u32)reg);
queue_work(dd->pport->hfi1_wq,
&dd->pport->link_bounce_work);
break;
}
loop++;
udelay(1);
}
if (pause)
/* Add additional delay to ensure chip returns all credits */
pause_for_credit_return(dd);
}
void sc_wait(struct hfi1_devdata *dd)
{
int i;
for (i = 0; i < dd->num_send_contexts; i++) {
struct send_context *sc = dd->send_contexts[i].sc;
if (!sc)
continue;
sc_wait_for_packet_egress(sc, 0);
}
}
/*
* Restart a context after it has been halted due to error.
*
* If the first step fails - wait for the halt to be asserted, return early.
* Otherwise complain about timeouts but keep going.
*
* It is expected that allocations (enabled flag bit) have been shut off
* already (only applies to kernel contexts).
*/
int sc_restart(struct send_context *sc)
{
struct hfi1_devdata *dd = sc->dd;
u64 reg;
u32 loop;
int count;
/* bounce off if not halted, or being free'd */
if (!(sc->flags & SCF_HALTED) || (sc->flags & SCF_IN_FREE))
return -EINVAL;
dd_dev_info(dd, "restarting send context %u(%u)\n", sc->sw_index,
sc->hw_context);
/*
* Step 1: Wait for the context to actually halt.
*
* The error interrupt is asynchronous to actually setting halt
* on the context.
*/
loop = 0;
while (1) {
reg = read_kctxt_csr(dd, sc->hw_context, SC(STATUS));
if (reg & SC(STATUS_CTXT_HALTED_SMASK))
break;
if (loop > 100) {
dd_dev_err(dd, "%s: context %u(%u) not halting, skipping\n",
__func__, sc->sw_index, sc->hw_context);
return -ETIME;
}
loop++;
udelay(1);
}
/*
* Step 2: Ensure no users are still trying to write to PIO.
*
* For kernel contexts, we have already turned off buffer allocation.
* Now wait for the buffer count to go to zero.
*
* For user contexts, the user handling code has cut off write access
* to the context's PIO pages before calling this routine and will
* restore write access after this routine returns.
*/
if (sc->type != SC_USER) {
/* kernel context */
loop = 0;
while (1) {
count = get_buffers_allocated(sc);
if (count == 0)
break;
if (loop > 100) {
dd_dev_err(dd,
"%s: context %u(%u) timeout waiting for PIO buffers to zero, remaining %d\n",
__func__, sc->sw_index,
sc->hw_context, count);
}
loop++;
udelay(1);
}
}
/*
* Step 3: Wait for all packets to egress.
* This is done while disabling the send context
*
* Step 4: Disable the context
*
* This is a superset of the halt. After the disable, the
* errors can be cleared.
*/
sc_disable(sc);
/*
* Step 5: Enable the context
*
* This enable will clear the halted flag and per-send context
* error flags.
*/
return sc_enable(sc);
}
/*
* PIO freeze processing. To be called after the TXE block is fully frozen.
* Go through all frozen send contexts and disable them. The contexts are
* already stopped by the freeze.
*/
void pio_freeze(struct hfi1_devdata *dd)
{
struct send_context *sc;
int i;
for (i = 0; i < dd->num_send_contexts; i++) {
sc = dd->send_contexts[i].sc;
/*
* Don't disable unallocated, unfrozen, or user send contexts.
* User send contexts will be disabled when the process
* calls into the driver to reset its context.
*/
if (!sc || !(sc->flags & SCF_FROZEN) || sc->type == SC_USER)
continue;
/* only need to disable, the context is already stopped */
sc_disable(sc);
}
}
/*
* Unfreeze PIO for kernel send contexts. The precondition for calling this
* is that all PIO send contexts have been disabled and the SPC freeze has
* been cleared. Now perform the last step and re-enable each kernel context.
* User (PSM) processing will occur when PSM calls into the kernel to
* acknowledge the freeze.
*/
void pio_kernel_unfreeze(struct hfi1_devdata *dd)
{
struct send_context *sc;
int i;
for (i = 0; i < dd->num_send_contexts; i++) {
sc = dd->send_contexts[i].sc;
if (!sc || !(sc->flags & SCF_FROZEN) || sc->type == SC_USER)
continue;
sc_enable(sc); /* will clear the sc frozen flag */
}
}
/*
* Wait for the SendPioInitCtxt.PioInitInProgress bit to clear.
* Returns:
* -ETIMEDOUT - if we wait too long
* -EIO - if there was an error
*/
static int pio_init_wait_progress(struct hfi1_devdata *dd)
{
u64 reg;
int max, count = 0;
/* max is the longest possible HW init time / delay */
max = (dd->icode == ICODE_FPGA_EMULATION) ? 120 : 5;
while (1) {
reg = read_csr(dd, SEND_PIO_INIT_CTXT);
if (!(reg & SEND_PIO_INIT_CTXT_PIO_INIT_IN_PROGRESS_SMASK))
break;
if (count >= max)
return -ETIMEDOUT;
udelay(5);
count++;
}
return reg & SEND_PIO_INIT_CTXT_PIO_INIT_ERR_SMASK ? -EIO : 0;
}
/*
* Reset all of the send contexts to their power-on state. Used
* only during manual init - no lock against sc_enable needed.
*/
void pio_reset_all(struct hfi1_devdata *dd)
{
int ret;
/* make sure the init engine is not busy */
ret = pio_init_wait_progress(dd);
/* ignore any timeout */
if (ret == -EIO) {
/* clear the error */
write_csr(dd, SEND_PIO_ERR_CLEAR,
SEND_PIO_ERR_CLEAR_PIO_INIT_SM_IN_ERR_SMASK);
}
/* reset init all */
write_csr(dd, SEND_PIO_INIT_CTXT,
SEND_PIO_INIT_CTXT_PIO_ALL_CTXT_INIT_SMASK);
udelay(2);
ret = pio_init_wait_progress(dd);
if (ret < 0) {
dd_dev_err(dd,
"PIO send context init %s while initializing all PIO blocks\n",
ret == -ETIMEDOUT ? "is stuck" : "had an error");
}
}
/* enable the context */
int sc_enable(struct send_context *sc)
{
u64 sc_ctrl, reg, pio;
struct hfi1_devdata *dd;
unsigned long flags;
int ret = 0;
if (!sc)
return -EINVAL;
dd = sc->dd;
/*
* Obtain the allocator lock to guard against any allocation
* attempts (which should not happen prior to context being
* enabled). On the release/disable side we don't need to
* worry about locking since the releaser will not do anything
* if the context accounting values have not changed.
*/
spin_lock_irqsave(&sc->alloc_lock, flags);
sc_ctrl = read_kctxt_csr(dd, sc->hw_context, SC(CTRL));
if ((sc_ctrl & SC(CTRL_CTXT_ENABLE_SMASK)))
goto unlock; /* already enabled */
/* IMPORTANT: only clear free and fill if transitioning 0 -> 1 */
*sc->hw_free = 0;
sc->free = 0;
sc->alloc_free = 0;
sc->fill = 0;
sc->fill_wrap = 0;
sc->sr_head = 0;
sc->sr_tail = 0;
sc->flags = 0;
/* the alloc lock insures no fast path allocation */
reset_buffers_allocated(sc);
/*
* Clear all per-context errors. Some of these will be set when
* we are re-enabling after a context halt. Now that the context
* is disabled, the halt will not clear until after the PIO init
* engine runs below.
*/
reg = read_kctxt_csr(dd, sc->hw_context, SC(ERR_STATUS));
if (reg)
write_kctxt_csr(dd, sc->hw_context, SC(ERR_CLEAR), reg);
/*
* The HW PIO initialization engine can handle only one init
* request at a time. Serialize access to each device's engine.
*/
spin_lock(&dd->sc_init_lock);
/*
* Since access to this code block is serialized and
* each access waits for the initialization to complete
* before releasing the lock, the PIO initialization engine
* should not be in use, so we don't have to wait for the
* InProgress bit to go down.
*/
pio = ((sc->hw_context & SEND_PIO_INIT_CTXT_PIO_CTXT_NUM_MASK) <<
SEND_PIO_INIT_CTXT_PIO_CTXT_NUM_SHIFT) |
SEND_PIO_INIT_CTXT_PIO_SINGLE_CTXT_INIT_SMASK;
write_csr(dd, SEND_PIO_INIT_CTXT, pio);
/*
* Wait until the engine is done. Give the chip the required time
* so, hopefully, we read the register just once.
*/
udelay(2);
ret = pio_init_wait_progress(dd);
spin_unlock(&dd->sc_init_lock);
if (ret) {
dd_dev_err(dd,
"sctxt%u(%u): Context not enabled due to init failure %d\n",
sc->sw_index, sc->hw_context, ret);
goto unlock;
}
/*
* All is well. Enable the context.
*/
sc_ctrl |= SC(CTRL_CTXT_ENABLE_SMASK);
write_kctxt_csr(dd, sc->hw_context, SC(CTRL), sc_ctrl);
/*
* Read SendCtxtCtrl to force the write out and prevent a timing
* hazard where a PIO write may reach the context before the enable.
*/
read_kctxt_csr(dd, sc->hw_context, SC(CTRL));
sc->flags |= SCF_ENABLED;
unlock:
spin_unlock_irqrestore(&sc->alloc_lock, flags);
return ret;
}
/* force a credit return on the context */
void sc_return_credits(struct send_context *sc)
{
if (!sc)
return;
/* a 0->1 transition schedules a credit return */
write_kctxt_csr(sc->dd, sc->hw_context, SC(CREDIT_FORCE),
SC(CREDIT_FORCE_FORCE_RETURN_SMASK));
/*
* Ensure that the write is flushed and the credit return is
* scheduled. We care more about the 0 -> 1 transition.
*/
read_kctxt_csr(sc->dd, sc->hw_context, SC(CREDIT_FORCE));
/* set back to 0 for next time */
write_kctxt_csr(sc->dd, sc->hw_context, SC(CREDIT_FORCE), 0);
}
/* allow all in-flight packets to drain on the context */
void sc_flush(struct send_context *sc)
{
if (!sc)
return;
sc_wait_for_packet_egress(sc, 1);
}
/* drop all packets on the context, no waiting until they are sent */
void sc_drop(struct send_context *sc)
{
if (!sc)
return;
dd_dev_info(sc->dd, "%s: context %u(%u) - not implemented\n",
__func__, sc->sw_index, sc->hw_context);
}
/*
* Start the software reaction to a context halt or SPC freeze:
* - mark the context as halted or frozen
* - stop buffer allocations
*
* Called from the error interrupt. Other work is deferred until
* out of the interrupt.
*/
void sc_stop(struct send_context *sc, int flag)
{
unsigned long flags;
/* mark the context */
sc->flags |= flag;
/* stop buffer allocations */
spin_lock_irqsave(&sc->alloc_lock, flags);
sc->flags &= ~SCF_ENABLED;
spin_unlock_irqrestore(&sc->alloc_lock, flags);
wake_up(&sc->halt_wait);
}
#define BLOCK_DWORDS (PIO_BLOCK_SIZE / sizeof(u32))
#define dwords_to_blocks(x) DIV_ROUND_UP(x, BLOCK_DWORDS)
/*
* The send context buffer "allocator".
*
* @sc: the PIO send context we are allocating from
* @len: length of whole packet - including PBC - in dwords
* @cb: optional callback to call when the buffer is finished sending
* @arg: argument for cb
*
* Return a pointer to a PIO buffer if successful, NULL if not enough room.
*/
struct pio_buf *sc_buffer_alloc(struct send_context *sc, u32 dw_len,
pio_release_cb cb, void *arg)
{
struct pio_buf *pbuf = NULL;
unsigned long flags;
unsigned long avail;
unsigned long blocks = dwords_to_blocks(dw_len);
u32 fill_wrap;
int trycount = 0;
u32 head, next;
spin_lock_irqsave(&sc->alloc_lock, flags);
if (!(sc->flags & SCF_ENABLED)) {
spin_unlock_irqrestore(&sc->alloc_lock, flags);
goto done;
}
retry:
avail = (unsigned long)sc->credits - (sc->fill - sc->alloc_free);
if (blocks > avail) {
/* not enough room */
if (unlikely(trycount)) { /* already tried to get more room */
spin_unlock_irqrestore(&sc->alloc_lock, flags);
goto done;
}
/* copy from receiver cache line and recalculate */
sc->alloc_free = ACCESS_ONCE(sc->free);
avail =
(unsigned long)sc->credits -
(sc->fill - sc->alloc_free);
if (blocks > avail) {
/* still no room, actively update */
sc_release_update(sc);
sc->alloc_free = ACCESS_ONCE(sc->free);
trycount++;
goto retry;
}
}
/* there is enough room */
preempt_disable();
this_cpu_inc(*sc->buffers_allocated);
/* read this once */
head = sc->sr_head;
/* "allocate" the buffer */
sc->fill += blocks;
fill_wrap = sc->fill_wrap;
sc->fill_wrap += blocks;
if (sc->fill_wrap >= sc->credits)
sc->fill_wrap = sc->fill_wrap - sc->credits;
/*
* Fill the parts that the releaser looks at before moving the head.
* The only necessary piece is the sent_at field. The credits
* we have just allocated cannot have been returned yet, so the
* cb and arg will not be looked at for a "while". Put them
* on this side of the memory barrier anyway.
*/
pbuf = &sc->sr[head].pbuf;
pbuf->sent_at = sc->fill;
pbuf->cb = cb;
pbuf->arg = arg;
pbuf->sc = sc; /* could be filled in at sc->sr init time */
/* make sure this is in memory before updating the head */
/* calculate next head index, do not store */
next = head + 1;
if (next >= sc->sr_size)
next = 0;
/*
* update the head - must be last! - the releaser can look at fields
* in pbuf once we move the head
*/
smp_wmb();
sc->sr_head = next;
spin_unlock_irqrestore(&sc->alloc_lock, flags);
/* finish filling in the buffer outside the lock */
pbuf->start = sc->base_addr + fill_wrap * PIO_BLOCK_SIZE;
pbuf->end = sc->base_addr + sc->size;
pbuf->qw_written = 0;
pbuf->carry_bytes = 0;
pbuf->carry.val64 = 0;
done:
return pbuf;
}
/*
* There are at least two entities that can turn on credit return
* interrupts and they can overlap. Avoid problems by implementing
* a count scheme that is enforced by a lock. The lock is needed because
* the count and CSR write must be paired.
*/
/*
* Start credit return interrupts. This is managed by a count. If already
* on, just increment the count.
*/
void sc_add_credit_return_intr(struct send_context *sc)
{
unsigned long flags;
/* lock must surround both the count change and the CSR update */
spin_lock_irqsave(&sc->credit_ctrl_lock, flags);
if (sc->credit_intr_count == 0) {
sc->credit_ctrl |= SC(CREDIT_CTRL_CREDIT_INTR_SMASK);
write_kctxt_csr(sc->dd, sc->hw_context,
SC(CREDIT_CTRL), sc->credit_ctrl);
}
sc->credit_intr_count++;
spin_unlock_irqrestore(&sc->credit_ctrl_lock, flags);
}
/*
* Stop credit return interrupts. This is managed by a count. Decrement the
* count, if the last user, then turn the credit interrupts off.
*/
void sc_del_credit_return_intr(struct send_context *sc)
{
unsigned long flags;
WARN_ON(sc->credit_intr_count == 0);
/* lock must surround both the count change and the CSR update */
spin_lock_irqsave(&sc->credit_ctrl_lock, flags);
sc->credit_intr_count--;
if (sc->credit_intr_count == 0) {
sc->credit_ctrl &= ~SC(CREDIT_CTRL_CREDIT_INTR_SMASK);
write_kctxt_csr(sc->dd, sc->hw_context,
SC(CREDIT_CTRL), sc->credit_ctrl);
}
spin_unlock_irqrestore(&sc->credit_ctrl_lock, flags);
}
/*
* The caller must be careful when calling this. All needint calls
* must be paired with !needint.
*/
void hfi1_sc_wantpiobuf_intr(struct send_context *sc, u32 needint)
{
if (needint)
sc_add_credit_return_intr(sc);
else
sc_del_credit_return_intr(sc);
trace_hfi1_wantpiointr(sc, needint, sc->credit_ctrl);
if (needint) {
mmiowb();
sc_return_credits(sc);
}
}
/**
* sc_piobufavail - callback when a PIO buffer is available
* @sc: the send context
*
* This is called from the interrupt handler when a PIO buffer is
* available after hfi1_verbs_send() returned an error that no buffers were
* available. Disable the interrupt if there are no more QPs waiting.
*/
static void sc_piobufavail(struct send_context *sc)
{
struct hfi1_devdata *dd = sc->dd;
struct hfi1_ibdev *dev = &dd->verbs_dev;
struct list_head *list;
struct rvt_qp *qps[PIO_WAIT_BATCH_SIZE];
struct rvt_qp *qp;
struct hfi1_qp_priv *priv;
unsigned long flags;
unsigned i, n = 0;
if (dd->send_contexts[sc->sw_index].type != SC_KERNEL &&
dd->send_contexts[sc->sw_index].type != SC_VL15)
return;
list = &sc->piowait;
/*
* Note: checking that the piowait list is empty and clearing
* the buffer available interrupt needs to be atomic or we
* could end up with QPs on the wait list with the interrupt
* disabled.
*/
write_seqlock_irqsave(&dev->iowait_lock, flags);
while (!list_empty(list)) {
struct iowait *wait;
if (n == ARRAY_SIZE(qps))
break;
wait = list_first_entry(list, struct iowait, list);
qp = iowait_to_qp(wait);
priv = qp->priv;
list_del_init(&priv->s_iowait.list);
priv->s_iowait.lock = NULL;
/* refcount held until actual wake up */
qps[n++] = qp;
}
/*
* If there had been waiters and there are more
* insure that we redo the force to avoid a potential hang.
*/
if (n) {
hfi1_sc_wantpiobuf_intr(sc, 0);
if (!list_empty(list))
hfi1_sc_wantpiobuf_intr(sc, 1);
}
write_sequnlock_irqrestore(&dev->iowait_lock, flags);
for (i = 0; i < n; i++)
hfi1_qp_wakeup(qps[i],
RVT_S_WAIT_PIO | RVT_S_WAIT_PIO_DRAIN);
}
/* translate a send credit update to a bit code of reasons */
static inline int fill_code(u64 hw_free)
{
int code = 0;
if (hw_free & CR_STATUS_SMASK)
code |= PRC_STATUS_ERR;
if (hw_free & CR_CREDIT_RETURN_DUE_TO_PBC_SMASK)
code |= PRC_PBC;
if (hw_free & CR_CREDIT_RETURN_DUE_TO_THRESHOLD_SMASK)
code |= PRC_THRESHOLD;
if (hw_free & CR_CREDIT_RETURN_DUE_TO_ERR_SMASK)
code |= PRC_FILL_ERR;
if (hw_free & CR_CREDIT_RETURN_DUE_TO_FORCE_SMASK)
code |= PRC_SC_DISABLE;
return code;
}
/* use the jiffies compare to get the wrap right */
#define sent_before(a, b) time_before(a, b) /* a < b */
/*
* The send context buffer "releaser".
*/
void sc_release_update(struct send_context *sc)
{
struct pio_buf *pbuf;
u64 hw_free;
u32 head, tail;
unsigned long old_free;
unsigned long free;
unsigned long extra;
unsigned long flags;
int code;
if (!sc)
return;
spin_lock_irqsave(&sc->release_lock, flags);
/* update free */
hw_free = le64_to_cpu(*sc->hw_free); /* volatile read */
old_free = sc->free;
extra = (((hw_free & CR_COUNTER_SMASK) >> CR_COUNTER_SHIFT)
- (old_free & CR_COUNTER_MASK))
& CR_COUNTER_MASK;
free = old_free + extra;
trace_hfi1_piofree(sc, extra);
/* call sent buffer callbacks */
code = -1; /* code not yet set */
head = ACCESS_ONCE(sc->sr_head); /* snapshot the head */
tail = sc->sr_tail;
while (head != tail) {
pbuf = &sc->sr[tail].pbuf;
if (sent_before(free, pbuf->sent_at)) {
/* not sent yet */
break;
}
if (pbuf->cb) {
if (code < 0) /* fill in code on first user */
code = fill_code(hw_free);
(*pbuf->cb)(pbuf->arg, code);
}
tail++;
if (tail >= sc->sr_size)
tail = 0;
}
sc->sr_tail = tail;
/* make sure tail is updated before free */
smp_wmb();
sc->free = free;
spin_unlock_irqrestore(&sc->release_lock, flags);
sc_piobufavail(sc);
}
/*
* Send context group releaser. Argument is the send context that caused
* the interrupt. Called from the send context interrupt handler.
*
* Call release on all contexts in the group.
*
* This routine takes the sc_lock without an irqsave because it is only
* called from an interrupt handler. Adjust if that changes.
*/
void sc_group_release_update(struct hfi1_devdata *dd, u32 hw_context)
{
struct send_context *sc;
u32 sw_index;
u32 gc, gc_end;
spin_lock(&dd->sc_lock);
sw_index = dd->hw_to_sw[hw_context];
if (unlikely(sw_index >= dd->num_send_contexts)) {
dd_dev_err(dd, "%s: invalid hw (%u) to sw (%u) mapping\n",
__func__, hw_context, sw_index);
goto done;
}
sc = dd->send_contexts[sw_index].sc;
if (unlikely(!sc))
goto done;
gc = group_context(hw_context, sc->group);
gc_end = gc + group_size(sc->group);
for (; gc < gc_end; gc++) {
sw_index = dd->hw_to_sw[gc];
if (unlikely(sw_index >= dd->num_send_contexts)) {
dd_dev_err(dd,
"%s: invalid hw (%u) to sw (%u) mapping\n",
__func__, hw_context, sw_index);
continue;
}
sc_release_update(dd->send_contexts[sw_index].sc);
}
done:
spin_unlock(&dd->sc_lock);
}
/*
* pio_select_send_context_vl() - select send context
* @dd: devdata
* @selector: a spreading factor
* @vl: this vl
*
* This function returns a send context based on the selector and a vl.
* The mapping fields are protected by RCU
*/
struct send_context *pio_select_send_context_vl(struct hfi1_devdata *dd,
u32 selector, u8 vl)
{
struct pio_vl_map *m;
struct pio_map_elem *e;
struct send_context *rval;
/*
* NOTE This should only happen if SC->VL changed after the initial
* checks on the QP/AH
* Default will return VL0's send context below
*/
if (unlikely(vl >= num_vls)) {
rval = NULL;
goto done;
}
rcu_read_lock();
m = rcu_dereference(dd->pio_map);
if (unlikely(!m)) {
rcu_read_unlock();
return dd->vld[0].sc;
}
e = m->map[vl & m->mask];
rval = e->ksc[selector & e->mask];
rcu_read_unlock();
done:
rval = !rval ? dd->vld[0].sc : rval;
return rval;
}
/*
* pio_select_send_context_sc() - select send context
* @dd: devdata
* @selector: a spreading factor
* @sc5: the 5 bit sc
*
* This function returns an send context based on the selector and an sc
*/
struct send_context *pio_select_send_context_sc(struct hfi1_devdata *dd,
u32 selector, u8 sc5)
{
u8 vl = sc_to_vlt(dd, sc5);
return pio_select_send_context_vl(dd, selector, vl);
}
/*
* Free the indicated map struct
*/
static void pio_map_free(struct pio_vl_map *m)
{
int i;
for (i = 0; m && i < m->actual_vls; i++)
kfree(m->map[i]);
kfree(m);
}
/*
* Handle RCU callback
*/
static void pio_map_rcu_callback(struct rcu_head *list)
{
struct pio_vl_map *m = container_of(list, struct pio_vl_map, list);
pio_map_free(m);
}
/*
* Set credit return threshold for the kernel send context
*/
static void set_threshold(struct hfi1_devdata *dd, int scontext, int i)
{
u32 thres;
thres = min(sc_percent_to_threshold(dd->kernel_send_context[scontext],
50),
sc_mtu_to_threshold(dd->kernel_send_context[scontext],
dd->vld[i].mtu,
dd->rcd[0]->rcvhdrqentsize));
sc_set_cr_threshold(dd->kernel_send_context[scontext], thres);
}
/*
* pio_map_init - called when #vls change
* @dd: hfi1_devdata
* @port: port number
* @num_vls: number of vls
* @vl_scontexts: per vl send context mapping (optional)
*
* This routine changes the mapping based on the number of vls.
*
* vl_scontexts is used to specify a non-uniform vl/send context
* loading. NULL implies auto computing the loading and giving each
* VL an uniform distribution of send contexts per VL.
*
* The auto algorithm computers the sc_per_vl and the number of extra
* send contexts. Any extra send contexts are added from the last VL
* on down
*
* rcu locking is used here to control access to the mapping fields.
*
* If either the num_vls or num_send_contexts are non-power of 2, the
* array sizes in the struct pio_vl_map and the struct pio_map_elem are
* rounded up to the next highest power of 2 and the first entry is
* reused in a round robin fashion.
*
* If an error occurs the map change is not done and the mapping is not
* chaged.
*
*/
int pio_map_init(struct hfi1_devdata *dd, u8 port, u8 num_vls, u8 *vl_scontexts)
{
int i, j;
int extra, sc_per_vl;
int scontext = 1;
int num_kernel_send_contexts = 0;
u8 lvl_scontexts[OPA_MAX_VLS];
struct pio_vl_map *oldmap, *newmap;
if (!vl_scontexts) {
for (i = 0; i < dd->num_send_contexts; i++)
if (dd->send_contexts[i].type == SC_KERNEL)
num_kernel_send_contexts++;
/* truncate divide */
sc_per_vl = num_kernel_send_contexts / num_vls;
/* extras */
extra = num_kernel_send_contexts % num_vls;
vl_scontexts = lvl_scontexts;
/* add extras from last vl down */
for (i = num_vls - 1; i >= 0; i--, extra--)
vl_scontexts[i] = sc_per_vl + (extra > 0 ? 1 : 0);
}
/* build new map */
newmap = kzalloc(sizeof(*newmap) +
roundup_pow_of_two(num_vls) *
sizeof(struct pio_map_elem *),
GFP_KERNEL);
if (!newmap)
goto bail;
newmap->actual_vls = num_vls;
newmap->vls = roundup_pow_of_two(num_vls);
newmap->mask = (1 << ilog2(newmap->vls)) - 1;
for (i = 0; i < newmap->vls; i++) {
/* save for wrap around */
int first_scontext = scontext;
if (i < newmap->actual_vls) {
int sz = roundup_pow_of_two(vl_scontexts[i]);
/* only allocate once */
newmap->map[i] = kzalloc(sizeof(*newmap->map[i]) +
sz * sizeof(struct
send_context *),
GFP_KERNEL);
if (!newmap->map[i])
goto bail;
newmap->map[i]->mask = (1 << ilog2(sz)) - 1;
/*
* assign send contexts and
* adjust credit return threshold
*/
for (j = 0; j < sz; j++) {
if (dd->kernel_send_context[scontext]) {
newmap->map[i]->ksc[j] =
dd->kernel_send_context[scontext];
set_threshold(dd, scontext, i);
}
if (++scontext >= first_scontext +
vl_scontexts[i])
/* wrap back to first send context */
scontext = first_scontext;
}
} else {
/* just re-use entry without allocating */
newmap->map[i] = newmap->map[i % num_vls];
}
scontext = first_scontext + vl_scontexts[i];
}
/* newmap in hand, save old map */
spin_lock_irq(&dd->pio_map_lock);
oldmap = rcu_dereference_protected(dd->pio_map,
lockdep_is_held(&dd->pio_map_lock));
/* publish newmap */
rcu_assign_pointer(dd->pio_map, newmap);
spin_unlock_irq(&dd->pio_map_lock);
/* success, free any old map after grace period */
if (oldmap)
call_rcu(&oldmap->list, pio_map_rcu_callback);
return 0;
bail:
/* free any partial allocation */
pio_map_free(newmap);
return -ENOMEM;
}
void free_pio_map(struct hfi1_devdata *dd)
{
/* Free PIO map if allocated */
if (rcu_access_pointer(dd->pio_map)) {
spin_lock_irq(&dd->pio_map_lock);
pio_map_free(rcu_access_pointer(dd->pio_map));
RCU_INIT_POINTER(dd->pio_map, NULL);
spin_unlock_irq(&dd->pio_map_lock);
synchronize_rcu();
}
kfree(dd->kernel_send_context);
dd->kernel_send_context = NULL;
}
int init_pervl_scs(struct hfi1_devdata *dd)
{
int i;
u64 mask, all_vl_mask = (u64)0x80ff; /* VLs 0-7, 15 */
u64 data_vls_mask = (u64)0x00ff; /* VLs 0-7 */
u32 ctxt;
struct hfi1_pportdata *ppd = dd->pport;
dd->vld[15].sc = sc_alloc(dd, SC_VL15,
dd->rcd[0]->rcvhdrqentsize, dd->node);
if (!dd->vld[15].sc)
return -ENOMEM;
hfi1_init_ctxt(dd->vld[15].sc);
dd->vld[15].mtu = enum_to_mtu(OPA_MTU_2048);
dd->kernel_send_context = kzalloc_node(dd->num_send_contexts *
sizeof(struct send_context *),
GFP_KERNEL, dd->node);
if (!dd->kernel_send_context)
goto freesc15;
dd->kernel_send_context[0] = dd->vld[15].sc;
for (i = 0; i < num_vls; i++) {
/*
* Since this function does not deal with a specific
* receive context but we need the RcvHdrQ entry size,
* use the size from rcd[0]. It is guaranteed to be
* valid at this point and will remain the same for all
* receive contexts.
*/
dd->vld[i].sc = sc_alloc(dd, SC_KERNEL,
dd->rcd[0]->rcvhdrqentsize, dd->node);
if (!dd->vld[i].sc)
goto nomem;
dd->kernel_send_context[i + 1] = dd->vld[i].sc;
hfi1_init_ctxt(dd->vld[i].sc);
/* non VL15 start with the max MTU */
dd->vld[i].mtu = hfi1_max_mtu;
}
for (i = num_vls; i < INIT_SC_PER_VL * num_vls; i++) {
dd->kernel_send_context[i + 1] =
sc_alloc(dd, SC_KERNEL, dd->rcd[0]->rcvhdrqentsize, dd->node);
if (!dd->kernel_send_context[i + 1])
goto nomem;
hfi1_init_ctxt(dd->kernel_send_context[i + 1]);
}
sc_enable(dd->vld[15].sc);
ctxt = dd->vld[15].sc->hw_context;
mask = all_vl_mask & ~(1LL << 15);
write_kctxt_csr(dd, ctxt, SC(CHECK_VL), mask);
dd_dev_info(dd,
"Using send context %u(%u) for VL15\n",
dd->vld[15].sc->sw_index, ctxt);
for (i = 0; i < num_vls; i++) {
sc_enable(dd->vld[i].sc);
ctxt = dd->vld[i].sc->hw_context;
mask = all_vl_mask & ~(data_vls_mask);
write_kctxt_csr(dd, ctxt, SC(CHECK_VL), mask);
}
for (i = num_vls; i < INIT_SC_PER_VL * num_vls; i++) {
sc_enable(dd->kernel_send_context[i + 1]);
ctxt = dd->kernel_send_context[i + 1]->hw_context;
mask = all_vl_mask & ~(data_vls_mask);
write_kctxt_csr(dd, ctxt, SC(CHECK_VL), mask);
}
if (pio_map_init(dd, ppd->port - 1, num_vls, NULL))
goto nomem;
return 0;
nomem:
for (i = 0; i < num_vls; i++) {
sc_free(dd->vld[i].sc);
dd->vld[i].sc = NULL;
}
for (i = num_vls; i < INIT_SC_PER_VL * num_vls; i++)
sc_free(dd->kernel_send_context[i + 1]);
kfree(dd->kernel_send_context);
dd->kernel_send_context = NULL;
freesc15:
sc_free(dd->vld[15].sc);
return -ENOMEM;
}
int init_credit_return(struct hfi1_devdata *dd)
{
int ret;
int i;
dd->cr_base = kcalloc(
node_affinity.num_possible_nodes,
sizeof(struct credit_return_base),
GFP_KERNEL);
if (!dd->cr_base) {
ret = -ENOMEM;
goto done;
}
for_each_node_with_cpus(i) {
int bytes = TXE_NUM_CONTEXTS * sizeof(struct credit_return);
set_dev_node(&dd->pcidev->dev, i);
dd->cr_base[i].va = dma_zalloc_coherent(
&dd->pcidev->dev,
bytes,
&dd->cr_base[i].dma,
GFP_KERNEL);
if (!dd->cr_base[i].va) {
set_dev_node(&dd->pcidev->dev, dd->node);
dd_dev_err(dd,
"Unable to allocate credit return DMA range for NUMA %d\n",
i);
ret = -ENOMEM;
goto done;
}
}
set_dev_node(&dd->pcidev->dev, dd->node);
ret = 0;
done:
return ret;
}
void free_credit_return(struct hfi1_devdata *dd)
{
int i;
if (!dd->cr_base)
return;
for (i = 0; i < node_affinity.num_possible_nodes; i++) {
if (dd->cr_base[i].va) {
dma_free_coherent(&dd->pcidev->dev,
TXE_NUM_CONTEXTS *
sizeof(struct credit_return),
dd->cr_base[i].va,
dd->cr_base[i].dma);
}
}
kfree(dd->cr_base);
dd->cr_base = NULL;
}