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|
/*
* Intel I/OAT DMA Linux driver
* Copyright(c) 2004 - 2009 Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, 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.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*
* The full GNU General Public License is included in this distribution in
* the file called "COPYING".
*
*/
/*
* This driver supports an Intel I/OAT DMA engine (versions >= 2), which
* does asynchronous data movement and checksumming operations.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/dmaengine.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/workqueue.h>
#include <linux/i7300_idle.h>
#include "dma.h"
#include "dma_v2.h"
#include "registers.h"
#include "hw.h"
static int ioat_ring_alloc_order = 8;
module_param(ioat_ring_alloc_order, int, 0644);
MODULE_PARM_DESC(ioat_ring_alloc_order,
"ioat2+: allocate 2^n descriptors per channel (default: n=8)");
static void __ioat2_issue_pending(struct ioat2_dma_chan *ioat)
{
void * __iomem reg_base = ioat->base.reg_base;
ioat->pending = 0;
ioat->dmacount += ioat2_ring_pending(ioat);
ioat->issued = ioat->head;
/* make descriptor updates globally visible before notifying channel */
wmb();
writew(ioat->dmacount, reg_base + IOAT_CHAN_DMACOUNT_OFFSET);
dev_dbg(to_dev(&ioat->base),
"%s: head: %#x tail: %#x issued: %#x count: %#x\n",
__func__, ioat->head, ioat->tail, ioat->issued, ioat->dmacount);
}
static void ioat2_issue_pending(struct dma_chan *chan)
{
struct ioat2_dma_chan *ioat = to_ioat2_chan(chan);
spin_lock_bh(&ioat->ring_lock);
if (ioat->pending == 1)
__ioat2_issue_pending(ioat);
spin_unlock_bh(&ioat->ring_lock);
}
/**
* ioat2_update_pending - log pending descriptors
* @ioat: ioat2+ channel
*
* set pending to '1' unless pending is already set to '2', pending == 2
* indicates that submission is temporarily blocked due to an in-flight
* reset. If we are already above the ioat_pending_level threshold then
* just issue pending.
*
* called with ring_lock held
*/
static void ioat2_update_pending(struct ioat2_dma_chan *ioat)
{
if (unlikely(ioat->pending == 2))
return;
else if (ioat2_ring_pending(ioat) > ioat_pending_level)
__ioat2_issue_pending(ioat);
else
ioat->pending = 1;
}
static void __ioat2_start_null_desc(struct ioat2_dma_chan *ioat)
{
void __iomem *reg_base = ioat->base.reg_base;
struct ioat_ring_ent *desc;
struct ioat_dma_descriptor *hw;
int idx;
if (ioat2_ring_space(ioat) < 1) {
dev_err(to_dev(&ioat->base),
"Unable to start null desc - ring full\n");
return;
}
dev_dbg(to_dev(&ioat->base), "%s: head: %#x tail: %#x issued: %#x\n",
__func__, ioat->head, ioat->tail, ioat->issued);
idx = ioat2_desc_alloc(ioat, 1);
desc = ioat2_get_ring_ent(ioat, idx);
hw = desc->hw;
hw->ctl = 0;
hw->ctl_f.null = 1;
hw->ctl_f.int_en = 1;
hw->ctl_f.compl_write = 1;
/* set size to non-zero value (channel returns error when size is 0) */
hw->size = NULL_DESC_BUFFER_SIZE;
hw->src_addr = 0;
hw->dst_addr = 0;
async_tx_ack(&desc->txd);
writel(((u64) desc->txd.phys) & 0x00000000FFFFFFFF,
reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
writel(((u64) desc->txd.phys) >> 32,
reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
dump_desc_dbg(ioat, desc);
__ioat2_issue_pending(ioat);
}
static void ioat2_start_null_desc(struct ioat2_dma_chan *ioat)
{
spin_lock_bh(&ioat->ring_lock);
__ioat2_start_null_desc(ioat);
spin_unlock_bh(&ioat->ring_lock);
}
static void ioat2_cleanup(struct ioat2_dma_chan *ioat);
/**
* ioat2_reset_part2 - reinit the channel after a reset
*/
static void ioat2_reset_part2(struct work_struct *work)
{
struct ioat_chan_common *chan;
struct ioat2_dma_chan *ioat;
chan = container_of(work, struct ioat_chan_common, work.work);
ioat = container_of(chan, struct ioat2_dma_chan, base);
/* ensure that ->tail points to the stalled descriptor
* (ioat->pending is set to 2 at this point so no new
* descriptors will be issued while we perform this cleanup)
*/
ioat2_cleanup(ioat);
spin_lock_bh(&chan->cleanup_lock);
spin_lock_bh(&ioat->ring_lock);
/* set the tail to be re-issued */
ioat->issued = ioat->tail;
ioat->dmacount = 0;
dev_dbg(to_dev(&ioat->base),
"%s: head: %#x tail: %#x issued: %#x count: %#x\n",
__func__, ioat->head, ioat->tail, ioat->issued, ioat->dmacount);
if (ioat2_ring_pending(ioat)) {
struct ioat_ring_ent *desc;
desc = ioat2_get_ring_ent(ioat, ioat->tail);
writel(((u64) desc->txd.phys) & 0x00000000FFFFFFFF,
chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
writel(((u64) desc->txd.phys) >> 32,
chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
__ioat2_issue_pending(ioat);
} else
__ioat2_start_null_desc(ioat);
spin_unlock_bh(&ioat->ring_lock);
spin_unlock_bh(&chan->cleanup_lock);
dev_info(to_dev(chan),
"chan%d reset - %d descs waiting, %d total desc\n",
chan_num(chan), ioat->dmacount, 1 << ioat->alloc_order);
}
/**
* ioat2_reset_channel - restart a channel
* @ioat: IOAT DMA channel handle
*/
static void ioat2_reset_channel(struct ioat2_dma_chan *ioat)
{
u32 chansts, chanerr;
struct ioat_chan_common *chan = &ioat->base;
u16 active;
spin_lock_bh(&ioat->ring_lock);
active = ioat2_ring_active(ioat);
spin_unlock_bh(&ioat->ring_lock);
if (!active)
return;
chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
chansts = *chan->completion & IOAT_CHANSTS_DMA_TRANSFER_STATUS;
if (chanerr) {
dev_err(to_dev(chan),
"chan%d, CHANSTS = 0x%08x CHANERR = 0x%04x, clearing\n",
chan_num(chan), chansts, chanerr);
writel(chanerr, chan->reg_base + IOAT_CHANERR_OFFSET);
}
spin_lock_bh(&ioat->ring_lock);
ioat->pending = 2;
writeb(IOAT_CHANCMD_RESET,
chan->reg_base
+ IOAT_CHANCMD_OFFSET(chan->device->version));
spin_unlock_bh(&ioat->ring_lock);
schedule_delayed_work(&chan->work, RESET_DELAY);
}
/**
* ioat2_chan_watchdog - watch for stuck channels
*/
static void ioat2_chan_watchdog(struct work_struct *work)
{
struct ioatdma_device *device =
container_of(work, struct ioatdma_device, work.work);
struct ioat2_dma_chan *ioat;
struct ioat_chan_common *chan;
u16 active;
int i;
dev_dbg(&device->pdev->dev, "%s\n", __func__);
for (i = 0; i < device->common.chancnt; i++) {
chan = ioat_chan_by_index(device, i);
ioat = container_of(chan, struct ioat2_dma_chan, base);
/*
* for version 2.0 if there are descriptors yet to be processed
* and the last completed hasn't changed since the last watchdog
* if they haven't hit the pending level
* issue the pending to push them through
* else
* try resetting the channel
*/
spin_lock_bh(&ioat->ring_lock);
active = ioat2_ring_active(ioat);
spin_unlock_bh(&ioat->ring_lock);
if (active &&
chan->last_completion &&
chan->last_completion == chan->watchdog_completion) {
if (ioat->pending == 1)
ioat2_issue_pending(&chan->common);
else {
ioat2_reset_channel(ioat);
chan->watchdog_completion = 0;
}
} else {
chan->last_compl_desc_addr_hw = 0;
chan->watchdog_completion = chan->last_completion;
}
chan->watchdog_last_tcp_cookie = chan->watchdog_tcp_cookie;
}
schedule_delayed_work(&device->work, WATCHDOG_DELAY);
}
/**
* ioat2_cleanup - clean finished descriptors (advance tail pointer)
* @chan: ioat channel to be cleaned up
*/
static void ioat2_cleanup(struct ioat2_dma_chan *ioat)
{
struct ioat_chan_common *chan = &ioat->base;
unsigned long phys_complete;
struct ioat_ring_ent *desc;
bool seen_current = false;
u16 active;
int i;
struct dma_async_tx_descriptor *tx;
prefetch(chan->completion);
spin_lock_bh(&chan->cleanup_lock);
phys_complete = ioat_get_current_completion(chan);
if (phys_complete == chan->last_completion) {
spin_unlock_bh(&chan->cleanup_lock);
/*
* perhaps we're stuck so hard that the watchdog can't go off?
* try to catch it after WATCHDOG_DELAY seconds
*/
if (chan->device->version < IOAT_VER_3_0) {
unsigned long tmo;
tmo = chan->last_completion_time + HZ*WATCHDOG_DELAY;
if (time_after(jiffies, tmo)) {
ioat2_chan_watchdog(&(chan->device->work.work));
chan->last_completion_time = jiffies;
}
}
return;
}
chan->last_completion_time = jiffies;
spin_lock_bh(&ioat->ring_lock);
dev_dbg(to_dev(chan), "%s: head: %#x tail: %#x issued: %#x\n",
__func__, ioat->head, ioat->tail, ioat->issued);
active = ioat2_ring_active(ioat);
for (i = 0; i < active && !seen_current; i++) {
prefetch(ioat2_get_ring_ent(ioat, ioat->tail + i + 1));
desc = ioat2_get_ring_ent(ioat, ioat->tail + i);
tx = &desc->txd;
dump_desc_dbg(ioat, desc);
if (tx->cookie) {
ioat_dma_unmap(chan, tx->flags, desc->len, desc->hw);
chan->completed_cookie = tx->cookie;
tx->cookie = 0;
if (tx->callback) {
tx->callback(tx->callback_param);
tx->callback = NULL;
}
}
if (tx->phys == phys_complete)
seen_current = true;
}
ioat->tail += i;
BUG_ON(!seen_current); /* no active descs have written a completion? */
spin_unlock_bh(&ioat->ring_lock);
chan->last_completion = phys_complete;
spin_unlock_bh(&chan->cleanup_lock);
}
static void ioat2_cleanup_tasklet(unsigned long data)
{
struct ioat2_dma_chan *ioat = (void *) data;
ioat2_cleanup(ioat);
writew(IOAT_CHANCTRL_INT_DISABLE,
ioat->base.reg_base + IOAT_CHANCTRL_OFFSET);
}
/**
* ioat2_enumerate_channels - find and initialize the device's channels
* @device: the device to be enumerated
*/
static int ioat2_enumerate_channels(struct ioatdma_device *device)
{
struct ioat2_dma_chan *ioat;
struct device *dev = &device->pdev->dev;
struct dma_device *dma = &device->common;
u8 xfercap_log;
int i;
INIT_LIST_HEAD(&dma->channels);
dma->chancnt = readb(device->reg_base + IOAT_CHANCNT_OFFSET);
dma->chancnt &= 0x1f; /* bits [4:0] valid */
if (dma->chancnt > ARRAY_SIZE(device->idx)) {
dev_warn(dev, "(%d) exceeds max supported channels (%zu)\n",
dma->chancnt, ARRAY_SIZE(device->idx));
dma->chancnt = ARRAY_SIZE(device->idx);
}
xfercap_log = readb(device->reg_base + IOAT_XFERCAP_OFFSET);
xfercap_log &= 0x1f; /* bits [4:0] valid */
if (xfercap_log == 0)
return 0;
dev_dbg(dev, "%s: xfercap = %d\n", __func__, 1 << xfercap_log);
/* FIXME which i/oat version is i7300? */
#ifdef CONFIG_I7300_IDLE_IOAT_CHANNEL
if (i7300_idle_platform_probe(NULL, NULL, 1) == 0)
dma->chancnt--;
#endif
for (i = 0; i < dma->chancnt; i++) {
ioat = devm_kzalloc(dev, sizeof(*ioat), GFP_KERNEL);
if (!ioat)
break;
ioat_init_channel(device, &ioat->base, i,
ioat2_reset_part2,
ioat2_cleanup_tasklet,
(unsigned long) ioat);
ioat->xfercap_log = xfercap_log;
spin_lock_init(&ioat->ring_lock);
}
dma->chancnt = i;
return i;
}
static dma_cookie_t ioat2_tx_submit_unlock(struct dma_async_tx_descriptor *tx)
{
struct dma_chan *c = tx->chan;
struct ioat2_dma_chan *ioat = to_ioat2_chan(c);
dma_cookie_t cookie = c->cookie;
cookie++;
if (cookie < 0)
cookie = 1;
tx->cookie = cookie;
c->cookie = cookie;
dev_dbg(to_dev(&ioat->base), "%s: cookie: %d\n", __func__, cookie);
ioat2_update_pending(ioat);
spin_unlock_bh(&ioat->ring_lock);
return cookie;
}
static struct ioat_ring_ent *ioat2_alloc_ring_ent(struct dma_chan *chan)
{
struct ioat_dma_descriptor *hw;
struct ioat_ring_ent *desc;
struct ioatdma_device *dma;
dma_addr_t phys;
dma = to_ioatdma_device(chan->device);
hw = pci_pool_alloc(dma->dma_pool, GFP_KERNEL, &phys);
if (!hw)
return NULL;
memset(hw, 0, sizeof(*hw));
desc = kzalloc(sizeof(*desc), GFP_KERNEL);
if (!desc) {
pci_pool_free(dma->dma_pool, hw, phys);
return NULL;
}
dma_async_tx_descriptor_init(&desc->txd, chan);
desc->txd.tx_submit = ioat2_tx_submit_unlock;
desc->hw = hw;
desc->txd.phys = phys;
return desc;
}
static void ioat2_free_ring_ent(struct ioat_ring_ent *desc, struct dma_chan *chan)
{
struct ioatdma_device *dma;
dma = to_ioatdma_device(chan->device);
pci_pool_free(dma->dma_pool, desc->hw, desc->txd.phys);
kfree(desc);
}
/* ioat2_alloc_chan_resources - allocate/initialize ioat2 descriptor ring
* @chan: channel to be initialized
*/
static int ioat2_alloc_chan_resources(struct dma_chan *c)
{
struct ioat2_dma_chan *ioat = to_ioat2_chan(c);
struct ioat_chan_common *chan = &ioat->base;
struct ioat_ring_ent **ring;
u16 chanctrl;
u32 chanerr;
int descs;
int i;
/* have we already been set up? */
if (ioat->ring)
return 1 << ioat->alloc_order;
/* Setup register to interrupt and write completion status on error */
chanctrl = IOAT_CHANCTRL_ERR_INT_EN | IOAT_CHANCTRL_ANY_ERR_ABORT_EN |
IOAT_CHANCTRL_ERR_COMPLETION_EN;
writew(chanctrl, chan->reg_base + IOAT_CHANCTRL_OFFSET);
chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
if (chanerr) {
dev_err(to_dev(chan), "CHANERR = %x, clearing\n", chanerr);
writel(chanerr, chan->reg_base + IOAT_CHANERR_OFFSET);
}
/* allocate a completion writeback area */
/* doing 2 32bit writes to mmio since 1 64b write doesn't work */
chan->completion = pci_pool_alloc(chan->device->completion_pool,
GFP_KERNEL, &chan->completion_dma);
if (!chan->completion)
return -ENOMEM;
memset(chan->completion, 0, sizeof(*chan->completion));
writel(((u64) chan->completion_dma) & 0x00000000FFFFFFFF,
chan->reg_base + IOAT_CHANCMP_OFFSET_LOW);
writel(((u64) chan->completion_dma) >> 32,
chan->reg_base + IOAT_CHANCMP_OFFSET_HIGH);
ioat->alloc_order = ioat_get_alloc_order();
descs = 1 << ioat->alloc_order;
/* allocate the array to hold the software ring */
ring = kcalloc(descs, sizeof(*ring), GFP_KERNEL);
if (!ring)
return -ENOMEM;
for (i = 0; i < descs; i++) {
ring[i] = ioat2_alloc_ring_ent(c);
if (!ring[i]) {
while (i--)
ioat2_free_ring_ent(ring[i], c);
kfree(ring);
return -ENOMEM;
}
set_desc_id(ring[i], i);
}
/* link descs */
for (i = 0; i < descs-1; i++) {
struct ioat_ring_ent *next = ring[i+1];
struct ioat_dma_descriptor *hw = ring[i]->hw;
hw->next = next->txd.phys;
}
ring[i]->hw->next = ring[0]->txd.phys;
spin_lock_bh(&ioat->ring_lock);
ioat->ring = ring;
ioat->head = 0;
ioat->issued = 0;
ioat->tail = 0;
ioat->pending = 0;
spin_unlock_bh(&ioat->ring_lock);
tasklet_enable(&chan->cleanup_task);
ioat2_start_null_desc(ioat);
return descs;
}
/**
* ioat2_alloc_and_lock - common descriptor alloc boilerplate for ioat2,3 ops
* @idx: gets starting descriptor index on successful allocation
* @ioat: ioat2,3 channel (ring) to operate on
* @num_descs: allocation length
*/
static int ioat2_alloc_and_lock(u16 *idx, struct ioat2_dma_chan *ioat, int num_descs)
{
struct ioat_chan_common *chan = &ioat->base;
spin_lock_bh(&ioat->ring_lock);
if (unlikely(ioat2_ring_space(ioat) < num_descs)) {
if (printk_ratelimit())
dev_dbg(to_dev(chan),
"%s: ring full! num_descs: %d (%x:%x:%x)\n",
__func__, num_descs, ioat->head, ioat->tail,
ioat->issued);
spin_unlock_bh(&ioat->ring_lock);
/* do direct reclaim in the allocation failure case */
ioat2_cleanup(ioat);
return -ENOMEM;
}
dev_dbg(to_dev(chan), "%s: num_descs: %d (%x:%x:%x)\n",
__func__, num_descs, ioat->head, ioat->tail, ioat->issued);
*idx = ioat2_desc_alloc(ioat, num_descs);
return 0; /* with ioat->ring_lock held */
}
static struct dma_async_tx_descriptor *
ioat2_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest,
dma_addr_t dma_src, size_t len, unsigned long flags)
{
struct ioat2_dma_chan *ioat = to_ioat2_chan(c);
struct ioat_dma_descriptor *hw;
struct ioat_ring_ent *desc;
dma_addr_t dst = dma_dest;
dma_addr_t src = dma_src;
size_t total_len = len;
int num_descs;
u16 idx;
int i;
num_descs = ioat2_xferlen_to_descs(ioat, len);
if (likely(num_descs) &&
ioat2_alloc_and_lock(&idx, ioat, num_descs) == 0)
/* pass */;
else
return NULL;
for (i = 0; i < num_descs; i++) {
size_t copy = min_t(size_t, len, 1 << ioat->xfercap_log);
desc = ioat2_get_ring_ent(ioat, idx + i);
hw = desc->hw;
hw->size = copy;
hw->ctl = 0;
hw->src_addr = src;
hw->dst_addr = dst;
len -= copy;
dst += copy;
src += copy;
dump_desc_dbg(ioat, desc);
}
desc->txd.flags = flags;
desc->len = total_len;
hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT);
hw->ctl_f.compl_write = 1;
dump_desc_dbg(ioat, desc);
/* we leave the channel locked to ensure in order submission */
return &desc->txd;
}
/**
* ioat2_free_chan_resources - release all the descriptors
* @chan: the channel to be cleaned
*/
static void ioat2_free_chan_resources(struct dma_chan *c)
{
struct ioat2_dma_chan *ioat = to_ioat2_chan(c);
struct ioat_chan_common *chan = &ioat->base;
struct ioatdma_device *ioatdma_device = chan->device;
struct ioat_ring_ent *desc;
const u16 total_descs = 1 << ioat->alloc_order;
int descs;
int i;
/* Before freeing channel resources first check
* if they have been previously allocated for this channel.
*/
if (!ioat->ring)
return;
tasklet_disable(&chan->cleanup_task);
ioat2_cleanup(ioat);
/* Delay 100ms after reset to allow internal DMA logic to quiesce
* before removing DMA descriptor resources.
*/
writeb(IOAT_CHANCMD_RESET,
chan->reg_base + IOAT_CHANCMD_OFFSET(chan->device->version));
mdelay(100);
spin_lock_bh(&ioat->ring_lock);
descs = ioat2_ring_space(ioat);
dev_dbg(to_dev(chan), "freeing %d idle descriptors\n", descs);
for (i = 0; i < descs; i++) {
desc = ioat2_get_ring_ent(ioat, ioat->head + i);
ioat2_free_ring_ent(desc, c);
}
if (descs < total_descs)
dev_err(to_dev(chan), "Freeing %d in use descriptors!\n",
total_descs - descs);
for (i = 0; i < total_descs - descs; i++) {
desc = ioat2_get_ring_ent(ioat, ioat->tail + i);
dump_desc_dbg(ioat, desc);
ioat2_free_ring_ent(desc, c);
}
kfree(ioat->ring);
ioat->ring = NULL;
ioat->alloc_order = 0;
pci_pool_free(ioatdma_device->completion_pool,
chan->completion,
chan->completion_dma);
spin_unlock_bh(&ioat->ring_lock);
chan->last_completion = 0;
chan->completion_dma = 0;
ioat->pending = 0;
ioat->dmacount = 0;
chan->watchdog_completion = 0;
chan->last_compl_desc_addr_hw = 0;
chan->watchdog_tcp_cookie = 0;
chan->watchdog_last_tcp_cookie = 0;
}
static enum dma_status
ioat2_is_complete(struct dma_chan *c, dma_cookie_t cookie,
dma_cookie_t *done, dma_cookie_t *used)
{
struct ioat2_dma_chan *ioat = to_ioat2_chan(c);
if (ioat_is_complete(c, cookie, done, used) == DMA_SUCCESS)
return DMA_SUCCESS;
ioat2_cleanup(ioat);
return ioat_is_complete(c, cookie, done, used);
}
int ioat2_dma_probe(struct ioatdma_device *device, int dca)
{
struct pci_dev *pdev = device->pdev;
struct dma_device *dma;
struct dma_chan *c;
struct ioat_chan_common *chan;
int err;
device->enumerate_channels = ioat2_enumerate_channels;
dma = &device->common;
dma->device_prep_dma_memcpy = ioat2_dma_prep_memcpy_lock;
dma->device_issue_pending = ioat2_issue_pending;
dma->device_alloc_chan_resources = ioat2_alloc_chan_resources;
dma->device_free_chan_resources = ioat2_free_chan_resources;
dma->device_is_tx_complete = ioat2_is_complete;
err = ioat_probe(device);
if (err)
return err;
ioat_set_tcp_copy_break(2048);
list_for_each_entry(c, &dma->channels, device_node) {
chan = to_chan_common(c);
writel(IOAT_DCACTRL_CMPL_WRITE_ENABLE | IOAT_DMA_DCA_ANY_CPU,
chan->reg_base + IOAT_DCACTRL_OFFSET);
}
err = ioat_register(device);
if (err)
return err;
if (dca)
device->dca = ioat2_dca_init(pdev, device->reg_base);
INIT_DELAYED_WORK(&device->work, ioat2_chan_watchdog);
schedule_delayed_work(&device->work, WATCHDOG_DELAY);
return err;
}
int ioat3_dma_probe(struct ioatdma_device *device, int dca)
{
struct pci_dev *pdev = device->pdev;
struct dma_device *dma;
struct dma_chan *c;
struct ioat_chan_common *chan;
int err;
u16 dev_id;
device->enumerate_channels = ioat2_enumerate_channels;
dma = &device->common;
dma->device_prep_dma_memcpy = ioat2_dma_prep_memcpy_lock;
dma->device_issue_pending = ioat2_issue_pending;
dma->device_alloc_chan_resources = ioat2_alloc_chan_resources;
dma->device_free_chan_resources = ioat2_free_chan_resources;
dma->device_is_tx_complete = ioat2_is_complete;
/* -= IOAT ver.3 workarounds =- */
/* Write CHANERRMSK_INT with 3E07h to mask out the errors
* that can cause stability issues for IOAT ver.3
*/
pci_write_config_dword(pdev, IOAT_PCI_CHANERRMASK_INT_OFFSET, 0x3e07);
/* Clear DMAUNCERRSTS Cfg-Reg Parity Error status bit
* (workaround for spurious config parity error after restart)
*/
pci_read_config_word(pdev, IOAT_PCI_DEVICE_ID_OFFSET, &dev_id);
if (dev_id == PCI_DEVICE_ID_INTEL_IOAT_TBG0)
pci_write_config_dword(pdev, IOAT_PCI_DMAUNCERRSTS_OFFSET, 0x10);
err = ioat_probe(device);
if (err)
return err;
ioat_set_tcp_copy_break(262144);
list_for_each_entry(c, &dma->channels, device_node) {
chan = to_chan_common(c);
writel(IOAT_DMA_DCA_ANY_CPU,
chan->reg_base + IOAT_DCACTRL_OFFSET);
}
err = ioat_register(device);
if (err)
return err;
if (dca)
device->dca = ioat3_dca_init(pdev, device->reg_base);
return err;
}
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