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linux/drivers/dma/ioat_dma.c

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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, which does asynchronous
* copy 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 "ioatdma.h"
#include "ioatdma_registers.h"
#include "ioatdma_hw.h"
#define to_ioat_chan(chan) container_of(chan, struct ioat_dma_chan, common)
#define to_ioatdma_device(dev) container_of(dev, struct ioatdma_device, common)
#define to_ioat_desc(lh) container_of(lh, struct ioat_desc_sw, node)
#define tx_to_ioat_desc(tx) container_of(tx, struct ioat_desc_sw, async_tx)
#define chan_num(ch) ((int)((ch)->reg_base - (ch)->device->reg_base) / 0x80)
static int ioat_pending_level = 4;
module_param(ioat_pending_level, int, 0644);
MODULE_PARM_DESC(ioat_pending_level,
"high-water mark for pushing ioat descriptors (default: 4)");
#define RESET_DELAY msecs_to_jiffies(100)
#define WATCHDOG_DELAY round_jiffies(msecs_to_jiffies(2000))
static void ioat_dma_chan_reset_part2(struct work_struct *work);
static void ioat_dma_chan_watchdog(struct work_struct *work);
/*
* workaround for IOAT ver.3.0 null descriptor issue
* (channel returns error when size is 0)
*/
#define NULL_DESC_BUFFER_SIZE 1
/* internal functions */
static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan);
static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan);
static struct ioat_desc_sw *
ioat1_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan);
static struct ioat_desc_sw *
ioat2_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan);
static inline struct ioat_dma_chan *ioat_lookup_chan_by_index(
struct ioatdma_device *device,
int index)
{
return device->idx[index];
}
/**
* ioat_dma_do_interrupt - handler used for single vector interrupt mode
* @irq: interrupt id
* @data: interrupt data
*/
static irqreturn_t ioat_dma_do_interrupt(int irq, void *data)
{
struct ioatdma_device *instance = data;
struct ioat_dma_chan *ioat_chan;
unsigned long attnstatus;
int bit;
u8 intrctrl;
intrctrl = readb(instance->reg_base + IOAT_INTRCTRL_OFFSET);
if (!(intrctrl & IOAT_INTRCTRL_MASTER_INT_EN))
return IRQ_NONE;
if (!(intrctrl & IOAT_INTRCTRL_INT_STATUS)) {
writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
return IRQ_NONE;
}
attnstatus = readl(instance->reg_base + IOAT_ATTNSTATUS_OFFSET);
for_each_bit(bit, &attnstatus, BITS_PER_LONG) {
ioat_chan = ioat_lookup_chan_by_index(instance, bit);
tasklet_schedule(&ioat_chan->cleanup_task);
}
writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
return IRQ_HANDLED;
}
/**
* ioat_dma_do_interrupt_msix - handler used for vector-per-channel interrupt mode
* @irq: interrupt id
* @data: interrupt data
*/
static irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data)
{
struct ioat_dma_chan *ioat_chan = data;
tasklet_schedule(&ioat_chan->cleanup_task);
return IRQ_HANDLED;
}
static void ioat_dma_cleanup_tasklet(unsigned long data);
/**
* ioat_dma_enumerate_channels - find and initialize the device's channels
* @device: the device to be enumerated
*/
static int ioat_dma_enumerate_channels(struct ioatdma_device *device)
{
u8 xfercap_scale;
u32 xfercap;
int i;
struct ioat_dma_chan *ioat_chan;
/*
* IOAT ver.3 workarounds
*/
if (device->version == IOAT_VER_3_0) {
u32 chan_err_mask;
u16 dev_id;
u32 dmauncerrsts;
/*
* Write CHANERRMSK_INT with 3E07h to mask out the errors
* that can cause stability issues for IOAT ver.3
*/
chan_err_mask = 0x3E07;
pci_write_config_dword(device->pdev,
IOAT_PCI_CHANERRMASK_INT_OFFSET,
chan_err_mask);
/*
* Clear DMAUNCERRSTS Cfg-Reg Parity Error status bit
* (workaround for spurious config parity error after restart)
*/
pci_read_config_word(device->pdev,
IOAT_PCI_DEVICE_ID_OFFSET,
&dev_id);
if (dev_id == PCI_DEVICE_ID_INTEL_IOAT_TBG0) {
dmauncerrsts = 0x10;
pci_write_config_dword(device->pdev,
IOAT_PCI_DMAUNCERRSTS_OFFSET,
dmauncerrsts);
}
}
device->common.chancnt = readb(device->reg_base + IOAT_CHANCNT_OFFSET);
xfercap_scale = readb(device->reg_base + IOAT_XFERCAP_OFFSET);
xfercap = (xfercap_scale == 0 ? -1 : (1UL << xfercap_scale));
#ifdef CONFIG_I7300_IDLE_IOAT_CHANNEL
if (i7300_idle_platform_probe(NULL, NULL) == 0) {
device->common.chancnt--;
}
#endif
for (i = 0; i < device->common.chancnt; i++) {
ioat_chan = kzalloc(sizeof(*ioat_chan), GFP_KERNEL);
if (!ioat_chan) {
device->common.chancnt = i;
break;
}
ioat_chan->device = device;
ioat_chan->reg_base = device->reg_base + (0x80 * (i + 1));
ioat_chan->xfercap = xfercap;
ioat_chan->desccount = 0;
INIT_DELAYED_WORK(&ioat_chan->work, ioat_dma_chan_reset_part2);
if (ioat_chan->device->version == IOAT_VER_2_0)
writel(IOAT_DCACTRL_CMPL_WRITE_ENABLE |
IOAT_DMA_DCA_ANY_CPU,
ioat_chan->reg_base + IOAT_DCACTRL_OFFSET);
else if (ioat_chan->device->version == IOAT_VER_3_0)
writel(IOAT_DMA_DCA_ANY_CPU,
ioat_chan->reg_base + IOAT_DCACTRL_OFFSET);
spin_lock_init(&ioat_chan->cleanup_lock);
spin_lock_init(&ioat_chan->desc_lock);
INIT_LIST_HEAD(&ioat_chan->free_desc);
INIT_LIST_HEAD(&ioat_chan->used_desc);
/* This should be made common somewhere in dmaengine.c */
ioat_chan->common.device = &device->common;
list_add_tail(&ioat_chan->common.device_node,
&device->common.channels);
device->idx[i] = ioat_chan;
tasklet_init(&ioat_chan->cleanup_task,
ioat_dma_cleanup_tasklet,
(unsigned long) ioat_chan);
tasklet_disable(&ioat_chan->cleanup_task);
}
return device->common.chancnt;
}
/**
* ioat_dma_memcpy_issue_pending - push potentially unrecognized appended
* descriptors to hw
* @chan: DMA channel handle
*/
static inline void __ioat1_dma_memcpy_issue_pending(
struct ioat_dma_chan *ioat_chan)
{
ioat_chan->pending = 0;
writeb(IOAT_CHANCMD_APPEND, ioat_chan->reg_base + IOAT1_CHANCMD_OFFSET);
}
static void ioat1_dma_memcpy_issue_pending(struct dma_chan *chan)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
if (ioat_chan->pending > 0) {
spin_lock_bh(&ioat_chan->desc_lock);
__ioat1_dma_memcpy_issue_pending(ioat_chan);
spin_unlock_bh(&ioat_chan->desc_lock);
}
}
static inline void __ioat2_dma_memcpy_issue_pending(
struct ioat_dma_chan *ioat_chan)
{
ioat_chan->pending = 0;
writew(ioat_chan->dmacount,
ioat_chan->reg_base + IOAT_CHAN_DMACOUNT_OFFSET);
}
static void ioat2_dma_memcpy_issue_pending(struct dma_chan *chan)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
if (ioat_chan->pending > 0) {
spin_lock_bh(&ioat_chan->desc_lock);
__ioat2_dma_memcpy_issue_pending(ioat_chan);
spin_unlock_bh(&ioat_chan->desc_lock);
}
}
/**
* ioat_dma_chan_reset_part2 - reinit the channel after a reset
*/
static void ioat_dma_chan_reset_part2(struct work_struct *work)
{
struct ioat_dma_chan *ioat_chan =
container_of(work, struct ioat_dma_chan, work.work);
struct ioat_desc_sw *desc;
spin_lock_bh(&ioat_chan->cleanup_lock);
spin_lock_bh(&ioat_chan->desc_lock);
ioat_chan->completion_virt->low = 0;
ioat_chan->completion_virt->high = 0;
ioat_chan->pending = 0;
/*
* count the descriptors waiting, and be sure to do it
* right for both the CB1 line and the CB2 ring
*/
ioat_chan->dmacount = 0;
if (ioat_chan->used_desc.prev) {
desc = to_ioat_desc(ioat_chan->used_desc.prev);
do {
ioat_chan->dmacount++;
desc = to_ioat_desc(desc->node.next);
} while (&desc->node != ioat_chan->used_desc.next);
}
/*
* write the new starting descriptor address
* this puts channel engine into ARMED state
*/
desc = to_ioat_desc(ioat_chan->used_desc.prev);
switch (ioat_chan->device->version) {
case IOAT_VER_1_2:
writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
ioat_chan->reg_base + IOAT1_CHAINADDR_OFFSET_LOW);
writel(((u64) desc->async_tx.phys) >> 32,
ioat_chan->reg_base + IOAT1_CHAINADDR_OFFSET_HIGH);
writeb(IOAT_CHANCMD_START, ioat_chan->reg_base
+ IOAT_CHANCMD_OFFSET(ioat_chan->device->version));
break;
case IOAT_VER_2_0:
writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
writel(((u64) desc->async_tx.phys) >> 32,
ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
/* tell the engine to go with what's left to be done */
writew(ioat_chan->dmacount,
ioat_chan->reg_base + IOAT_CHAN_DMACOUNT_OFFSET);
break;
}
dev_err(&ioat_chan->device->pdev->dev,
"chan%d reset - %d descs waiting, %d total desc\n",
chan_num(ioat_chan), ioat_chan->dmacount, ioat_chan->desccount);
spin_unlock_bh(&ioat_chan->desc_lock);
spin_unlock_bh(&ioat_chan->cleanup_lock);
}
/**
* ioat_dma_reset_channel - restart a channel
* @ioat_chan: IOAT DMA channel handle
*/
static void ioat_dma_reset_channel(struct ioat_dma_chan *ioat_chan)
{
u32 chansts, chanerr;
if (!ioat_chan->used_desc.prev)
return;
chanerr = readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
chansts = (ioat_chan->completion_virt->low
& IOAT_CHANSTS_DMA_TRANSFER_STATUS);
if (chanerr) {
dev_err(&ioat_chan->device->pdev->dev,
"chan%d, CHANSTS = 0x%08x CHANERR = 0x%04x, clearing\n",
chan_num(ioat_chan), chansts, chanerr);
writel(chanerr, ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
}
/*
* whack it upside the head with a reset
* and wait for things to settle out.
* force the pending count to a really big negative
* to make sure no one forces an issue_pending
* while we're waiting.
*/
spin_lock_bh(&ioat_chan->desc_lock);
ioat_chan->pending = INT_MIN;
writeb(IOAT_CHANCMD_RESET,
ioat_chan->reg_base
+ IOAT_CHANCMD_OFFSET(ioat_chan->device->version));
spin_unlock_bh(&ioat_chan->desc_lock);
/* schedule the 2nd half instead of sleeping a long time */
schedule_delayed_work(&ioat_chan->work, RESET_DELAY);
}
/**
* ioat_dma_chan_watchdog - watch for stuck channels
*/
static void ioat_dma_chan_watchdog(struct work_struct *work)
{
struct ioatdma_device *device =
container_of(work, struct ioatdma_device, work.work);
struct ioat_dma_chan *ioat_chan;
int i;
union {
u64 full;
struct {
u32 low;
u32 high;
};
} completion_hw;
unsigned long compl_desc_addr_hw;
for (i = 0; i < device->common.chancnt; i++) {
ioat_chan = ioat_lookup_chan_by_index(device, i);
if (ioat_chan->device->version == IOAT_VER_1_2
/* have we started processing anything yet */
&& ioat_chan->last_completion
/* have we completed any since last watchdog cycle? */
&& (ioat_chan->last_completion ==
ioat_chan->watchdog_completion)
/* has TCP stuck on one cookie since last watchdog? */
&& (ioat_chan->watchdog_tcp_cookie ==
ioat_chan->watchdog_last_tcp_cookie)
&& (ioat_chan->watchdog_tcp_cookie !=
ioat_chan->completed_cookie)
/* is there something in the chain to be processed? */
/* CB1 chain always has at least the last one processed */
&& (ioat_chan->used_desc.prev != ioat_chan->used_desc.next)
&& ioat_chan->pending == 0) {
/*
* check CHANSTS register for completed
* descriptor address.
* if it is different than completion writeback,
* it is not zero
* and it has changed since the last watchdog
* we can assume that channel
* is still working correctly
* and the problem is in completion writeback.
* update completion writeback
* with actual CHANSTS value
* else
* try resetting the channel
*/
completion_hw.low = readl(ioat_chan->reg_base +
IOAT_CHANSTS_OFFSET_LOW(ioat_chan->device->version));
completion_hw.high = readl(ioat_chan->reg_base +
IOAT_CHANSTS_OFFSET_HIGH(ioat_chan->device->version));
#if (BITS_PER_LONG == 64)
compl_desc_addr_hw =
completion_hw.full
& IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
#else
compl_desc_addr_hw =
completion_hw.low & IOAT_LOW_COMPLETION_MASK;
#endif
if ((compl_desc_addr_hw != 0)
&& (compl_desc_addr_hw != ioat_chan->watchdog_completion)
&& (compl_desc_addr_hw != ioat_chan->last_compl_desc_addr_hw)) {
ioat_chan->last_compl_desc_addr_hw = compl_desc_addr_hw;
ioat_chan->completion_virt->low = completion_hw.low;
ioat_chan->completion_virt->high = completion_hw.high;
} else {
ioat_dma_reset_channel(ioat_chan);
ioat_chan->watchdog_completion = 0;
ioat_chan->last_compl_desc_addr_hw = 0;
}
/*
* 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
*/
} else if (ioat_chan->device->version == IOAT_VER_2_0
&& ioat_chan->used_desc.prev
&& ioat_chan->last_completion
&& ioat_chan->last_completion == ioat_chan->watchdog_completion) {
if (ioat_chan->pending < ioat_pending_level)
ioat2_dma_memcpy_issue_pending(&ioat_chan->common);
else {
ioat_dma_reset_channel(ioat_chan);
ioat_chan->watchdog_completion = 0;
}
} else {
ioat_chan->last_compl_desc_addr_hw = 0;
ioat_chan->watchdog_completion
= ioat_chan->last_completion;
}
ioat_chan->watchdog_last_tcp_cookie =
ioat_chan->watchdog_tcp_cookie;
}
schedule_delayed_work(&device->work, WATCHDOG_DELAY);
}
static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
struct ioat_desc_sw *first = tx_to_ioat_desc(tx);
struct ioat_desc_sw *prev, *new;
struct ioat_dma_descriptor *hw;
dma_cookie_t cookie;
LIST_HEAD(new_chain);
u32 copy;
size_t len;
dma_addr_t src, dst;
unsigned long orig_flags;
unsigned int desc_count = 0;
/* src and dest and len are stored in the initial descriptor */
len = first->len;
src = first->src;
dst = first->dst;
orig_flags = first->async_tx.flags;
new = first;
spin_lock_bh(&ioat_chan->desc_lock);
prev = to_ioat_desc(ioat_chan->used_desc.prev);
prefetch(prev->hw);
do {
copy = min_t(size_t, len, ioat_chan->xfercap);
async_tx_ack(&new->async_tx);
hw = new->hw;
hw->size = copy;
hw->ctl = 0;
hw->src_addr = src;
hw->dst_addr = dst;
hw->next = 0;
/* chain together the physical address list for the HW */
wmb();
prev->hw->next = (u64) new->async_tx.phys;
len -= copy;
dst += copy;
src += copy;
list_add_tail(&new->node, &new_chain);
desc_count++;
prev = new;
} while (len && (new = ioat1_dma_get_next_descriptor(ioat_chan)));
if (!new) {
dev_err(&ioat_chan->device->pdev->dev,
"tx submit failed\n");
spin_unlock_bh(&ioat_chan->desc_lock);
return -ENOMEM;
}
hw->ctl = IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
if (first->async_tx.callback) {
hw->ctl |= IOAT_DMA_DESCRIPTOR_CTL_INT_GN;
if (first != new) {
/* move callback into to last desc */
new->async_tx.callback = first->async_tx.callback;
new->async_tx.callback_param
= first->async_tx.callback_param;
first->async_tx.callback = NULL;
first->async_tx.callback_param = NULL;
}
}
new->tx_cnt = desc_count;
new->async_tx.flags = orig_flags; /* client is in control of this ack */
/* store the original values for use in later cleanup */
if (new != first) {
new->src = first->src;
new->dst = first->dst;
new->len = first->len;
}
/* cookie incr and addition to used_list must be atomic */
cookie = ioat_chan->common.cookie;
cookie++;
if (cookie < 0)
cookie = 1;
ioat_chan->common.cookie = new->async_tx.cookie = cookie;
/* write address into NextDescriptor field of last desc in chain */
to_ioat_desc(ioat_chan->used_desc.prev)->hw->next =
first->async_tx.phys;
list_splice_tail(&new_chain, &ioat_chan->used_desc);
ioat_chan->dmacount += desc_count;
ioat_chan->pending += desc_count;
if (ioat_chan->pending >= ioat_pending_level)
__ioat1_dma_memcpy_issue_pending(ioat_chan);
spin_unlock_bh(&ioat_chan->desc_lock);
return cookie;
}
static dma_cookie_t ioat2_tx_submit(struct dma_async_tx_descriptor *tx)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
struct ioat_desc_sw *first = tx_to_ioat_desc(tx);
struct ioat_desc_sw *new;
struct ioat_dma_descriptor *hw;
dma_cookie_t cookie;
u32 copy;
size_t len;
dma_addr_t src, dst;
unsigned long orig_flags;
unsigned int desc_count = 0;
/* src and dest and len are stored in the initial descriptor */
len = first->len;
src = first->src;
dst = first->dst;
orig_flags = first->async_tx.flags;
new = first;
/*
* ioat_chan->desc_lock is still in force in version 2 path
* it gets unlocked at end of this function
*/
do {
copy = min_t(size_t, len, ioat_chan->xfercap);
async_tx_ack(&new->async_tx);
hw = new->hw;
hw->size = copy;
hw->ctl = 0;
hw->src_addr = src;
hw->dst_addr = dst;
len -= copy;
dst += copy;
src += copy;
desc_count++;
} while (len && (new = ioat2_dma_get_next_descriptor(ioat_chan)));
if (!new) {
dev_err(&ioat_chan->device->pdev->dev,
"tx submit failed\n");
spin_unlock_bh(&ioat_chan->desc_lock);
return -ENOMEM;
}
hw->ctl |= IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
if (first->async_tx.callback) {
hw->ctl |= IOAT_DMA_DESCRIPTOR_CTL_INT_GN;
if (first != new) {
/* move callback into to last desc */
new->async_tx.callback = first->async_tx.callback;
new->async_tx.callback_param
= first->async_tx.callback_param;
first->async_tx.callback = NULL;
first->async_tx.callback_param = NULL;
}
}
new->tx_cnt = desc_count;
new->async_tx.flags = orig_flags; /* client is in control of this ack */
/* store the original values for use in later cleanup */
if (new != first) {
new->src = first->src;
new->dst = first->dst;
new->len = first->len;
}
/* cookie incr and addition to used_list must be atomic */
cookie = ioat_chan->common.cookie;
cookie++;
if (cookie < 0)
cookie = 1;
ioat_chan->common.cookie = new->async_tx.cookie = cookie;
ioat_chan->dmacount += desc_count;
ioat_chan->pending += desc_count;
if (ioat_chan->pending >= ioat_pending_level)
__ioat2_dma_memcpy_issue_pending(ioat_chan);
spin_unlock_bh(&ioat_chan->desc_lock);
return cookie;
}
/**
* ioat_dma_alloc_descriptor - allocate and return a sw and hw descriptor pair
* @ioat_chan: the channel supplying the memory pool for the descriptors
* @flags: allocation flags
*/
static struct ioat_desc_sw *ioat_dma_alloc_descriptor(
struct ioat_dma_chan *ioat_chan,
gfp_t flags)
{
struct ioat_dma_descriptor *desc;
struct ioat_desc_sw *desc_sw;
struct ioatdma_device *ioatdma_device;
dma_addr_t phys;
ioatdma_device = to_ioatdma_device(ioat_chan->common.device);
desc = pci_pool_alloc(ioatdma_device->dma_pool, flags, &phys);
if (unlikely(!desc))
return NULL;
desc_sw = kzalloc(sizeof(*desc_sw), flags);
if (unlikely(!desc_sw)) {
pci_pool_free(ioatdma_device->dma_pool, desc, phys);
return NULL;
}
memset(desc, 0, sizeof(*desc));
dma_async_tx_descriptor_init(&desc_sw->async_tx, &ioat_chan->common);
switch (ioat_chan->device->version) {
case IOAT_VER_1_2:
desc_sw->async_tx.tx_submit = ioat1_tx_submit;
break;
case IOAT_VER_2_0:
case IOAT_VER_3_0:
desc_sw->async_tx.tx_submit = ioat2_tx_submit;
break;
}
desc_sw->hw = desc;
desc_sw->async_tx.phys = phys;
return desc_sw;
}
static int ioat_initial_desc_count = 256;
module_param(ioat_initial_desc_count, int, 0644);
MODULE_PARM_DESC(ioat_initial_desc_count,
"initial descriptors per channel (default: 256)");
/**
* ioat2_dma_massage_chan_desc - link the descriptors into a circle
* @ioat_chan: the channel to be massaged
*/
static void ioat2_dma_massage_chan_desc(struct ioat_dma_chan *ioat_chan)
{
struct ioat_desc_sw *desc, *_desc;
/* setup used_desc */
ioat_chan->used_desc.next = ioat_chan->free_desc.next;
ioat_chan->used_desc.prev = NULL;
/* pull free_desc out of the circle so that every node is a hw
* descriptor, but leave it pointing to the list
*/
ioat_chan->free_desc.prev->next = ioat_chan->free_desc.next;
ioat_chan->free_desc.next->prev = ioat_chan->free_desc.prev;
/* circle link the hw descriptors */
desc = to_ioat_desc(ioat_chan->free_desc.next);
desc->hw->next = to_ioat_desc(desc->node.next)->async_tx.phys;
list_for_each_entry_safe(desc, _desc, ioat_chan->free_desc.next, node) {
desc->hw->next = to_ioat_desc(desc->node.next)->async_tx.phys;
}
}
/**
* ioat_dma_alloc_chan_resources - returns the number of allocated descriptors
* @chan: the channel to be filled out
*/
static int ioat_dma_alloc_chan_resources(struct dma_chan *chan)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
struct ioat_desc_sw *desc;
u16 chanctrl;
u32 chanerr;
int i;
LIST_HEAD(tmp_list);
/* have we already been set up? */
if (!list_empty(&ioat_chan->free_desc))
return ioat_chan->desccount;
/* 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, ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET);
chanerr = readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
if (chanerr) {
dev_err(&ioat_chan->device->pdev->dev,
"CHANERR = %x, clearing\n", chanerr);
writel(chanerr, ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
}
/* Allocate descriptors */
for (i = 0; i < ioat_initial_desc_count; i++) {
desc = ioat_dma_alloc_descriptor(ioat_chan, GFP_KERNEL);
if (!desc) {
dev_err(&ioat_chan->device->pdev->dev,
"Only %d initial descriptors\n", i);
break;
}
list_add_tail(&desc->node, &tmp_list);
}
spin_lock_bh(&ioat_chan->desc_lock);
ioat_chan->desccount = i;
list_splice(&tmp_list, &ioat_chan->free_desc);
if (ioat_chan->device->version != IOAT_VER_1_2)
ioat2_dma_massage_chan_desc(ioat_chan);
spin_unlock_bh(&ioat_chan->desc_lock);
/* allocate a completion writeback area */
/* doing 2 32bit writes to mmio since 1 64b write doesn't work */
ioat_chan->completion_virt =
pci_pool_alloc(ioat_chan->device->completion_pool,
GFP_KERNEL,
&ioat_chan->completion_addr);
memset(ioat_chan->completion_virt, 0,
sizeof(*ioat_chan->completion_virt));
writel(((u64) ioat_chan->completion_addr) & 0x00000000FFFFFFFF,
ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_LOW);
writel(((u64) ioat_chan->completion_addr) >> 32,
ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_HIGH);
tasklet_enable(&ioat_chan->cleanup_task);
ioat_dma_start_null_desc(ioat_chan); /* give chain to dma device */
return ioat_chan->desccount;
}
/**
* ioat_dma_free_chan_resources - release all the descriptors
* @chan: the channel to be cleaned
*/
static void ioat_dma_free_chan_resources(struct dma_chan *chan)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
struct ioatdma_device *ioatdma_device = to_ioatdma_device(chan->device);
struct ioat_desc_sw *desc, *_desc;
int in_use_descs = 0;
/* Before freeing channel resources first check
* if they have been previously allocated for this channel.
*/
if (ioat_chan->desccount == 0)
return;
tasklet_disable(&ioat_chan->cleanup_task);
ioat_dma_memcpy_cleanup(ioat_chan);
/* Delay 100ms after reset to allow internal DMA logic to quiesce
* before removing DMA descriptor resources.
*/
writeb(IOAT_CHANCMD_RESET,
ioat_chan->reg_base
+ IOAT_CHANCMD_OFFSET(ioat_chan->device->version));
mdelay(100);
spin_lock_bh(&ioat_chan->desc_lock);
switch (ioat_chan->device->version) {
case IOAT_VER_1_2:
list_for_each_entry_safe(desc, _desc,
&ioat_chan->used_desc, node) {
in_use_descs++;
list_del(&desc->node);
pci_pool_free(ioatdma_device->dma_pool, desc->hw,
desc->async_tx.phys);
kfree(desc);
}
list_for_each_entry_safe(desc, _desc,
&ioat_chan->free_desc, node) {
list_del(&desc->node);
pci_pool_free(ioatdma_device->dma_pool, desc->hw,
desc->async_tx.phys);
kfree(desc);
}
break;
case IOAT_VER_2_0:
case IOAT_VER_3_0:
list_for_each_entry_safe(desc, _desc,
ioat_chan->free_desc.next, node) {
list_del(&desc->node);
pci_pool_free(ioatdma_device->dma_pool, desc->hw,
desc->async_tx.phys);
kfree(desc);
}
desc = to_ioat_desc(ioat_chan->free_desc.next);
pci_pool_free(ioatdma_device->dma_pool, desc->hw,
desc->async_tx.phys);
kfree(desc);
INIT_LIST_HEAD(&ioat_chan->free_desc);
INIT_LIST_HEAD(&ioat_chan->used_desc);
break;
}
spin_unlock_bh(&ioat_chan->desc_lock);
pci_pool_free(ioatdma_device->completion_pool,
ioat_chan->completion_virt,
ioat_chan->completion_addr);
/* one is ok since we left it on there on purpose */
if (in_use_descs > 1)
dev_err(&ioat_chan->device->pdev->dev,
"Freeing %d in use descriptors!\n",
in_use_descs - 1);
ioat_chan->last_completion = ioat_chan->completion_addr = 0;
ioat_chan->pending = 0;
ioat_chan->dmacount = 0;
ioat_chan->desccount = 0;
ioat_chan->watchdog_completion = 0;
ioat_chan->last_compl_desc_addr_hw = 0;
ioat_chan->watchdog_tcp_cookie =
ioat_chan->watchdog_last_tcp_cookie = 0;
}
/**
* ioat_dma_get_next_descriptor - return the next available descriptor
* @ioat_chan: IOAT DMA channel handle
*
* Gets the next descriptor from the chain, and must be called with the
* channel's desc_lock held. Allocates more descriptors if the channel
* has run out.
*/
static struct ioat_desc_sw *
ioat1_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan)
{
struct ioat_desc_sw *new;
if (!list_empty(&ioat_chan->free_desc)) {
new = to_ioat_desc(ioat_chan->free_desc.next);
list_del(&new->node);
} else {
/* try to get another desc */
new = ioat_dma_alloc_descriptor(ioat_chan, GFP_ATOMIC);
if (!new) {
dev_err(&ioat_chan->device->pdev->dev,
"alloc failed\n");
return NULL;
}
}
prefetch(new->hw);
return new;
}
static struct ioat_desc_sw *
ioat2_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan)
{
struct ioat_desc_sw *new;
/*
* used.prev points to where to start processing
* used.next points to next free descriptor
* if used.prev == NULL, there are none waiting to be processed
* if used.next == used.prev.prev, there is only one free descriptor,
* and we need to use it to as a noop descriptor before
* linking in a new set of descriptors, since the device
* has probably already read the pointer to it
*/
if (ioat_chan->used_desc.prev &&
ioat_chan->used_desc.next == ioat_chan->used_desc.prev->prev) {
struct ioat_desc_sw *desc;
struct ioat_desc_sw *noop_desc;
int i;
/* set up the noop descriptor */
noop_desc = to_ioat_desc(ioat_chan->used_desc.next);
/* set size to non-zero value (channel returns error when size is 0) */
noop_desc->hw->size = NULL_DESC_BUFFER_SIZE;
noop_desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL;
noop_desc->hw->src_addr = 0;
noop_desc->hw->dst_addr = 0;
ioat_chan->used_desc.next = ioat_chan->used_desc.next->next;
ioat_chan->pending++;
ioat_chan->dmacount++;
/* try to get a few more descriptors */
for (i = 16; i; i--) {
desc = ioat_dma_alloc_descriptor(ioat_chan, GFP_ATOMIC);
if (!desc) {
dev_err(&ioat_chan->device->pdev->dev,
"alloc failed\n");
break;
}
list_add_tail(&desc->node, ioat_chan->used_desc.next);
desc->hw->next
= to_ioat_desc(desc->node.next)->async_tx.phys;
to_ioat_desc(desc->node.prev)->hw->next
= desc->async_tx.phys;
ioat_chan->desccount++;
}
ioat_chan->used_desc.next = noop_desc->node.next;
}
new = to_ioat_desc(ioat_chan->used_desc.next);
prefetch(new);
ioat_chan->used_desc.next = new->node.next;
if (ioat_chan->used_desc.prev == NULL)
ioat_chan->used_desc.prev = &new->node;
prefetch(new->hw);
return new;
}
static struct ioat_desc_sw *ioat_dma_get_next_descriptor(
struct ioat_dma_chan *ioat_chan)
{
if (!ioat_chan)
return NULL;
switch (ioat_chan->device->version) {
case IOAT_VER_1_2:
return ioat1_dma_get_next_descriptor(ioat_chan);
case IOAT_VER_2_0:
case IOAT_VER_3_0:
return ioat2_dma_get_next_descriptor(ioat_chan);
}
return NULL;
}
static struct dma_async_tx_descriptor *ioat1_dma_prep_memcpy(
struct dma_chan *chan,
dma_addr_t dma_dest,
dma_addr_t dma_src,
size_t len,
unsigned long flags)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
struct ioat_desc_sw *new;
spin_lock_bh(&ioat_chan->desc_lock);
new = ioat_dma_get_next_descriptor(ioat_chan);
spin_unlock_bh(&ioat_chan->desc_lock);
if (new) {
new->len = len;
new->dst = dma_dest;
new->src = dma_src;
new->async_tx.flags = flags;
return &new->async_tx;
} else {
dev_err(&ioat_chan->device->pdev->dev,
"chan%d - get_next_desc failed: %d descs waiting, %d total desc\n",
chan_num(ioat_chan), ioat_chan->dmacount, ioat_chan->desccount);
return NULL;
}
}
static struct dma_async_tx_descriptor *ioat2_dma_prep_memcpy(
struct dma_chan *chan,
dma_addr_t dma_dest,
dma_addr_t dma_src,
size_t len,
unsigned long flags)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
struct ioat_desc_sw *new;
spin_lock_bh(&ioat_chan->desc_lock);
new = ioat2_dma_get_next_descriptor(ioat_chan);
/*
* leave ioat_chan->desc_lock set in ioat 2 path
* it will get unlocked at end of tx_submit
*/
if (new) {
new->len = len;
new->dst = dma_dest;
new->src = dma_src;
new->async_tx.flags = flags;
return &new->async_tx;
} else {
spin_unlock_bh(&ioat_chan->desc_lock);
dev_err(&ioat_chan->device->pdev->dev,
"chan%d - get_next_desc failed: %d descs waiting, %d total desc\n",
chan_num(ioat_chan), ioat_chan->dmacount, ioat_chan->desccount);
return NULL;
}
}
static void ioat_dma_cleanup_tasklet(unsigned long data)
{
struct ioat_dma_chan *chan = (void *)data;
ioat_dma_memcpy_cleanup(chan);
writew(IOAT_CHANCTRL_INT_DISABLE,
chan->reg_base + IOAT_CHANCTRL_OFFSET);
}
static void
ioat_dma_unmap(struct ioat_dma_chan *ioat_chan, struct ioat_desc_sw *desc)
{
/*
* yes we are unmapping both _page and _single
* alloc'd regions with unmap_page. Is this
* *really* that bad?
*/
if (!(desc->async_tx.flags & DMA_COMPL_SKIP_DEST_UNMAP))
pci_unmap_page(ioat_chan->device->pdev,
pci_unmap_addr(desc, dst),
pci_unmap_len(desc, len),
PCI_DMA_FROMDEVICE);
if (!(desc->async_tx.flags & DMA_COMPL_SKIP_SRC_UNMAP))
pci_unmap_page(ioat_chan->device->pdev,
pci_unmap_addr(desc, src),
pci_unmap_len(desc, len),
PCI_DMA_TODEVICE);
}
/**
* ioat_dma_memcpy_cleanup - cleanup up finished descriptors
* @chan: ioat channel to be cleaned up
*/
static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan)
{
unsigned long phys_complete;
struct ioat_desc_sw *desc, *_desc;
dma_cookie_t cookie = 0;
unsigned long desc_phys;
struct ioat_desc_sw *latest_desc;
prefetch(ioat_chan->completion_virt);
if (!spin_trylock_bh(&ioat_chan->cleanup_lock))
return;
/* The completion writeback can happen at any time,
so reads by the driver need to be atomic operations
The descriptor physical addresses are limited to 32-bits
when the CPU can only do a 32-bit mov */
#if (BITS_PER_LONG == 64)
phys_complete =
ioat_chan->completion_virt->full
& IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
#else
phys_complete =
ioat_chan->completion_virt->low & IOAT_LOW_COMPLETION_MASK;
#endif
if ((ioat_chan->completion_virt->full
& IOAT_CHANSTS_DMA_TRANSFER_STATUS) ==
IOAT_CHANSTS_DMA_TRANSFER_STATUS_HALTED) {
dev_err(&ioat_chan->device->pdev->dev,
"Channel halted, chanerr = %x\n",
readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET));
/* TODO do something to salvage the situation */
}
if (phys_complete == ioat_chan->last_completion) {
spin_unlock_bh(&ioat_chan->cleanup_lock);
/*
* perhaps we're stuck so hard that the watchdog can't go off?
* try to catch it after 2 seconds
*/
if (ioat_chan->device->version != IOAT_VER_3_0) {
if (time_after(jiffies,
ioat_chan->last_completion_time + HZ*WATCHDOG_DELAY)) {
ioat_dma_chan_watchdog(&(ioat_chan->device->work.work));
ioat_chan->last_completion_time = jiffies;
}
}
return;
}
ioat_chan->last_completion_time = jiffies;
cookie = 0;
if (!spin_trylock_bh(&ioat_chan->desc_lock)) {
spin_unlock_bh(&ioat_chan->cleanup_lock);
return;
}
switch (ioat_chan->device->version) {
case IOAT_VER_1_2:
list_for_each_entry_safe(desc, _desc,
&ioat_chan->used_desc, node) {
/*
* Incoming DMA requests may use multiple descriptors,
* due to exceeding xfercap, perhaps. If so, only the
* last one will have a cookie, and require unmapping.
*/
if (desc->async_tx.cookie) {
cookie = desc->async_tx.cookie;
ioat_dma_unmap(ioat_chan, desc);
if (desc->async_tx.callback) {
desc->async_tx.callback(desc->async_tx.callback_param);
desc->async_tx.callback = NULL;
}
}
if (desc->async_tx.phys != phys_complete) {
/*
* a completed entry, but not the last, so clean
* up if the client is done with the descriptor
*/
if (async_tx_test_ack(&desc->async_tx)) {
list_move_tail(&desc->node,
&ioat_chan->free_desc);
} else
desc->async_tx.cookie = 0;
} else {
/*
* last used desc. Do not remove, so we can
* append from it, but don't look at it next
* time, either
*/
desc->async_tx.cookie = 0;
/* TODO check status bits? */
break;
}
}
break;
case IOAT_VER_2_0:
case IOAT_VER_3_0:
/* has some other thread has already cleaned up? */
if (ioat_chan->used_desc.prev == NULL)
break;
/* work backwards to find latest finished desc */
desc = to_ioat_desc(ioat_chan->used_desc.next);
latest_desc = NULL;
do {
desc = to_ioat_desc(desc->node.prev);
desc_phys = (unsigned long)desc->async_tx.phys
& IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
if (desc_phys == phys_complete) {
latest_desc = desc;
break;
}
} while (&desc->node != ioat_chan->used_desc.prev);
if (latest_desc != NULL) {
/* work forwards to clear finished descriptors */
for (desc = to_ioat_desc(ioat_chan->used_desc.prev);
&desc->node != latest_desc->node.next &&
&desc->node != ioat_chan->used_desc.next;
desc = to_ioat_desc(desc->node.next)) {
if (desc->async_tx.cookie) {
cookie = desc->async_tx.cookie;
desc->async_tx.cookie = 0;
ioat_dma_unmap(ioat_chan, desc);
if (desc->async_tx.callback) {
desc->async_tx.callback(desc->async_tx.callback_param);
desc->async_tx.callback = NULL;
}
}
}
/* move used.prev up beyond those that are finished */
if (&desc->node == ioat_chan->used_desc.next)
ioat_chan->used_desc.prev = NULL;
else
ioat_chan->used_desc.prev = &desc->node;
}
break;
}
spin_unlock_bh(&ioat_chan->desc_lock);
ioat_chan->last_completion = phys_complete;
if (cookie != 0)
ioat_chan->completed_cookie = cookie;
spin_unlock_bh(&ioat_chan->cleanup_lock);
}
/**
* ioat_dma_is_complete - poll the status of a IOAT DMA transaction
* @chan: IOAT DMA channel handle
* @cookie: DMA transaction identifier
* @done: if not %NULL, updated with last completed transaction
* @used: if not %NULL, updated with last used transaction
*/
static enum dma_status ioat_dma_is_complete(struct dma_chan *chan,
dma_cookie_t cookie,
dma_cookie_t *done,
dma_cookie_t *used)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
dma_cookie_t last_used;
dma_cookie_t last_complete;
enum dma_status ret;
last_used = chan->cookie;
last_complete = ioat_chan->completed_cookie;
ioat_chan->watchdog_tcp_cookie = cookie;
if (done)
*done = last_complete;
if (used)
*used = last_used;
ret = dma_async_is_complete(cookie, last_complete, last_used);
if (ret == DMA_SUCCESS)
return ret;
ioat_dma_memcpy_cleanup(ioat_chan);
last_used = chan->cookie;
last_complete = ioat_chan->completed_cookie;
if (done)
*done = last_complete;
if (used)
*used = last_used;
return dma_async_is_complete(cookie, last_complete, last_used);
}
static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan)
{
struct ioat_desc_sw *desc;
spin_lock_bh(&ioat_chan->desc_lock);
desc = ioat_dma_get_next_descriptor(ioat_chan);
if (!desc) {
dev_err(&ioat_chan->device->pdev->dev,
"Unable to start null desc - get next desc failed\n");
spin_unlock_bh(&ioat_chan->desc_lock);
return;
}
desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL
| IOAT_DMA_DESCRIPTOR_CTL_INT_GN
| IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
/* set size to non-zero value (channel returns error when size is 0) */
desc->hw->size = NULL_DESC_BUFFER_SIZE;
desc->hw->src_addr = 0;
desc->hw->dst_addr = 0;
async_tx_ack(&desc->async_tx);
switch (ioat_chan->device->version) {
case IOAT_VER_1_2:
desc->hw->next = 0;
list_add_tail(&desc->node, &ioat_chan->used_desc);
writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
ioat_chan->reg_base + IOAT1_CHAINADDR_OFFSET_LOW);
writel(((u64) desc->async_tx.phys) >> 32,
ioat_chan->reg_base + IOAT1_CHAINADDR_OFFSET_HIGH);
writeb(IOAT_CHANCMD_START, ioat_chan->reg_base
+ IOAT_CHANCMD_OFFSET(ioat_chan->device->version));
break;
case IOAT_VER_2_0:
case IOAT_VER_3_0:
writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
writel(((u64) desc->async_tx.phys) >> 32,
ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
ioat_chan->dmacount++;
__ioat2_dma_memcpy_issue_pending(ioat_chan);
break;
}
spin_unlock_bh(&ioat_chan->desc_lock);
}
/*
* Perform a IOAT transaction to verify the HW works.
*/
#define IOAT_TEST_SIZE 2000
static void ioat_dma_test_callback(void *dma_async_param)
{
struct completion *cmp = dma_async_param;
complete(cmp);
}
/**
* ioat_dma_self_test - Perform a IOAT transaction to verify the HW works.
* @device: device to be tested
*/
static int ioat_dma_self_test(struct ioatdma_device *device)
{
int i;
u8 *src;
u8 *dest;
struct dma_chan *dma_chan;
struct dma_async_tx_descriptor *tx;
dma_addr_t dma_dest, dma_src;
dma_cookie_t cookie;
int err = 0;
struct completion cmp;
unsigned long tmo;
src = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, GFP_KERNEL);
if (!src)
return -ENOMEM;
dest = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, GFP_KERNEL);
if (!dest) {
kfree(src);
return -ENOMEM;
}
/* Fill in src buffer */
for (i = 0; i < IOAT_TEST_SIZE; i++)
src[i] = (u8)i;
/* Start copy, using first DMA channel */
dma_chan = container_of(device->common.channels.next,
struct dma_chan,
device_node);
if (device->common.device_alloc_chan_resources(dma_chan) < 1) {
dev_err(&device->pdev->dev,
"selftest cannot allocate chan resource\n");
err = -ENODEV;
goto out;
}
dma_src = dma_map_single(dma_chan->device->dev, src, IOAT_TEST_SIZE,
DMA_TO_DEVICE);
dma_dest = dma_map_single(dma_chan->device->dev, dest, IOAT_TEST_SIZE,
DMA_FROM_DEVICE);
tx = device->common.device_prep_dma_memcpy(dma_chan, dma_dest, dma_src,
IOAT_TEST_SIZE, 0);
if (!tx) {
dev_err(&device->pdev->dev,
"Self-test prep failed, disabling\n");
err = -ENODEV;
goto free_resources;
}
async_tx_ack(tx);
init_completion(&cmp);
tx->callback = ioat_dma_test_callback;
tx->callback_param = &cmp;
cookie = tx->tx_submit(tx);
if (cookie < 0) {
dev_err(&device->pdev->dev,
"Self-test setup failed, disabling\n");
err = -ENODEV;
goto free_resources;
}
device->common.device_issue_pending(dma_chan);
tmo = wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000));
if (tmo == 0 ||
device->common.device_is_tx_complete(dma_chan, cookie, NULL, NULL)
!= DMA_SUCCESS) {
dev_err(&device->pdev->dev,
"Self-test copy timed out, disabling\n");
err = -ENODEV;
goto free_resources;
}
if (memcmp(src, dest, IOAT_TEST_SIZE)) {
dev_err(&device->pdev->dev,
"Self-test copy failed compare, disabling\n");
err = -ENODEV;
goto free_resources;
}
free_resources:
device->common.device_free_chan_resources(dma_chan);
out:
kfree(src);
kfree(dest);
return err;
}
static char ioat_interrupt_style[32] = "msix";
module_param_string(ioat_interrupt_style, ioat_interrupt_style,
sizeof(ioat_interrupt_style), 0644);
MODULE_PARM_DESC(ioat_interrupt_style,
"set ioat interrupt style: msix (default), "
"msix-single-vector, msi, intx)");
/**
* ioat_dma_setup_interrupts - setup interrupt handler
* @device: ioat device
*/
static int ioat_dma_setup_interrupts(struct ioatdma_device *device)
{
struct ioat_dma_chan *ioat_chan;
int err, i, j, msixcnt;
u8 intrctrl = 0;
if (!strcmp(ioat_interrupt_style, "msix"))
goto msix;
if (!strcmp(ioat_interrupt_style, "msix-single-vector"))
goto msix_single_vector;
if (!strcmp(ioat_interrupt_style, "msi"))
goto msi;
if (!strcmp(ioat_interrupt_style, "intx"))
goto intx;
dev_err(&device->pdev->dev, "invalid ioat_interrupt_style %s\n",
ioat_interrupt_style);
goto err_no_irq;
msix:
/* The number of MSI-X vectors should equal the number of channels */
msixcnt = device->common.chancnt;
for (i = 0; i < msixcnt; i++)
device->msix_entries[i].entry = i;
err = pci_enable_msix(device->pdev, device->msix_entries, msixcnt);
if (err < 0)
goto msi;
if (err > 0)
goto msix_single_vector;
for (i = 0; i < msixcnt; i++) {
ioat_chan = ioat_lookup_chan_by_index(device, i);
err = request_irq(device->msix_entries[i].vector,
ioat_dma_do_interrupt_msix,
0, "ioat-msix", ioat_chan);
if (err) {
for (j = 0; j < i; j++) {
ioat_chan =
ioat_lookup_chan_by_index(device, j);
free_irq(device->msix_entries[j].vector,
ioat_chan);
}
goto msix_single_vector;
}
}
intrctrl |= IOAT_INTRCTRL_MSIX_VECTOR_CONTROL;
device->irq_mode = msix_multi_vector;
goto done;
msix_single_vector:
device->msix_entries[0].entry = 0;
err = pci_enable_msix(device->pdev, device->msix_entries, 1);
if (err)
goto msi;
err = request_irq(device->msix_entries[0].vector, ioat_dma_do_interrupt,
0, "ioat-msix", device);
if (err) {
pci_disable_msix(device->pdev);
goto msi;
}
device->irq_mode = msix_single_vector;
goto done;
msi:
err = pci_enable_msi(device->pdev);
if (err)
goto intx;
err = request_irq(device->pdev->irq, ioat_dma_do_interrupt,
0, "ioat-msi", device);
if (err) {
pci_disable_msi(device->pdev);
goto intx;
}
/*
* CB 1.2 devices need a bit set in configuration space to enable MSI
*/
if (device->version == IOAT_VER_1_2) {
u32 dmactrl;
pci_read_config_dword(device->pdev,
IOAT_PCI_DMACTRL_OFFSET, &dmactrl);
dmactrl |= IOAT_PCI_DMACTRL_MSI_EN;
pci_write_config_dword(device->pdev,
IOAT_PCI_DMACTRL_OFFSET, dmactrl);
}
device->irq_mode = msi;
goto done;
intx:
err = request_irq(device->pdev->irq, ioat_dma_do_interrupt,
IRQF_SHARED, "ioat-intx", device);
if (err)
goto err_no_irq;
device->irq_mode = intx;
done:
intrctrl |= IOAT_INTRCTRL_MASTER_INT_EN;
writeb(intrctrl, device->reg_base + IOAT_INTRCTRL_OFFSET);
return 0;
err_no_irq:
/* Disable all interrupt generation */
writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
dev_err(&device->pdev->dev, "no usable interrupts\n");
device->irq_mode = none;
return -1;
}
/**
* ioat_dma_remove_interrupts - remove whatever interrupts were set
* @device: ioat device
*/
static void ioat_dma_remove_interrupts(struct ioatdma_device *device)
{
struct ioat_dma_chan *ioat_chan;
int i;
/* Disable all interrupt generation */
writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
switch (device->irq_mode) {
case msix_multi_vector:
for (i = 0; i < device->common.chancnt; i++) {
ioat_chan = ioat_lookup_chan_by_index(device, i);
free_irq(device->msix_entries[i].vector, ioat_chan);
}
pci_disable_msix(device->pdev);
break;
case msix_single_vector:
free_irq(device->msix_entries[0].vector, device);
pci_disable_msix(device->pdev);
break;
case msi:
free_irq(device->pdev->irq, device);
pci_disable_msi(device->pdev);
break;
case intx:
free_irq(device->pdev->irq, device);
break;
case none:
dev_warn(&device->pdev->dev,
"call to %s without interrupts setup\n", __func__);
}
device->irq_mode = none;
}
struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev,
void __iomem *iobase)
{
int err;
struct ioatdma_device *device;
device = kzalloc(sizeof(*device), GFP_KERNEL);
if (!device) {
err = -ENOMEM;
goto err_kzalloc;
}
device->pdev = pdev;
device->reg_base = iobase;
device->version = readb(device->reg_base + IOAT_VER_OFFSET);
/* DMA coherent memory pool for DMA descriptor allocations */
device->dma_pool = pci_pool_create("dma_desc_pool", pdev,
sizeof(struct ioat_dma_descriptor),
64, 0);
if (!device->dma_pool) {
err = -ENOMEM;
goto err_dma_pool;
}
device->completion_pool = pci_pool_create("completion_pool", pdev,
sizeof(u64), SMP_CACHE_BYTES,
SMP_CACHE_BYTES);
if (!device->completion_pool) {
err = -ENOMEM;
goto err_completion_pool;
}
INIT_LIST_HEAD(&device->common.channels);
ioat_dma_enumerate_channels(device);
device->common.device_alloc_chan_resources =
ioat_dma_alloc_chan_resources;
device->common.device_free_chan_resources =
ioat_dma_free_chan_resources;
device->common.dev = &pdev->dev;
dma_cap_set(DMA_MEMCPY, device->common.cap_mask);
device->common.device_is_tx_complete = ioat_dma_is_complete;
switch (device->version) {
case IOAT_VER_1_2:
device->common.device_prep_dma_memcpy = ioat1_dma_prep_memcpy;
device->common.device_issue_pending =
ioat1_dma_memcpy_issue_pending;
break;
case IOAT_VER_2_0:
case IOAT_VER_3_0:
device->common.device_prep_dma_memcpy = ioat2_dma_prep_memcpy;
device->common.device_issue_pending =
ioat2_dma_memcpy_issue_pending;
break;
}
dev_err(&device->pdev->dev,
"Intel(R) I/OAT DMA Engine found,"
" %d channels, device version 0x%02x, driver version %s\n",
device->common.chancnt, device->version, IOAT_DMA_VERSION);
if (!device->common.chancnt) {
dev_err(&device->pdev->dev,
"Intel(R) I/OAT DMA Engine problem found: "
"zero channels detected\n");
goto err_setup_interrupts;
}
err = ioat_dma_setup_interrupts(device);
if (err)
goto err_setup_interrupts;
err = ioat_dma_self_test(device);
if (err)
goto err_self_test;
ioat_set_tcp_copy_break(device);
dma_async_device_register(&device->common);
if (device->version != IOAT_VER_3_0) {
INIT_DELAYED_WORK(&device->work, ioat_dma_chan_watchdog);
schedule_delayed_work(&device->work,
WATCHDOG_DELAY);
}
return device;
err_self_test:
ioat_dma_remove_interrupts(device);
err_setup_interrupts:
pci_pool_destroy(device->completion_pool);
err_completion_pool:
pci_pool_destroy(device->dma_pool);
err_dma_pool:
kfree(device);
err_kzalloc:
dev_err(&pdev->dev,
"Intel(R) I/OAT DMA Engine initialization failed\n");
return NULL;
}
void ioat_dma_remove(struct ioatdma_device *device)
{
struct dma_chan *chan, *_chan;
struct ioat_dma_chan *ioat_chan;
if (device->version != IOAT_VER_3_0)
cancel_delayed_work(&device->work);
ioat_dma_remove_interrupts(device);
dma_async_device_unregister(&device->common);
pci_pool_destroy(device->dma_pool);
pci_pool_destroy(device->completion_pool);
iounmap(device->reg_base);
pci_release_regions(device->pdev);
pci_disable_device(device->pdev);
list_for_each_entry_safe(chan, _chan,
&device->common.channels, device_node) {
ioat_chan = to_ioat_chan(chan);
list_del(&chan->device_node);
kfree(ioat_chan);
}
kfree(device);
}
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