blob: 66c5bb53211bceef2f3494a9a43fc4f9d4b6724e [file] [log] [blame]
/*
* Intel I/OAT DMA Linux driver
* Copyright(c) 2004 - 2007 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 "ioatdma.h"
#include "ioatdma_registers.h"
#include "ioatdma_hw.h"
#define INITIAL_IOAT_DESC_COUNT 128
#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)
/* 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_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;
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));
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;
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;
}
static void ioat_set_src(dma_addr_t addr,
struct dma_async_tx_descriptor *tx,
int index)
{
struct ioat_desc_sw *iter, *desc = tx_to_ioat_desc(tx);
struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
pci_unmap_addr_set(desc, src, addr);
list_for_each_entry(iter, &desc->async_tx.tx_list, node) {
iter->hw->src_addr = addr;
addr += ioat_chan->xfercap;
}
}
static void ioat_set_dest(dma_addr_t addr,
struct dma_async_tx_descriptor *tx,
int index)
{
struct ioat_desc_sw *iter, *desc = tx_to_ioat_desc(tx);
struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
pci_unmap_addr_set(desc, dst, addr);
list_for_each_entry(iter, &desc->async_tx.tx_list, node) {
iter->hw->dst_addr = addr;
addr += ioat_chan->xfercap;
}
}
static dma_cookie_t ioat_tx_submit(struct dma_async_tx_descriptor *tx)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
struct ioat_desc_sw *desc = tx_to_ioat_desc(tx);
int append = 0;
dma_cookie_t cookie;
struct ioat_desc_sw *group_start;
group_start = list_entry(desc->async_tx.tx_list.next,
struct ioat_desc_sw, node);
spin_lock_bh(&ioat_chan->desc_lock);
/* 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 = desc->async_tx.cookie = cookie;
/* write address into NextDescriptor field of last desc in chain */
to_ioat_desc(ioat_chan->used_desc.prev)->hw->next =
group_start->async_tx.phys;
list_splice_init(&desc->async_tx.tx_list, ioat_chan->used_desc.prev);
ioat_chan->pending += desc->tx_cnt;
if (ioat_chan->pending >= 4) {
append = 1;
ioat_chan->pending = 0;
}
spin_unlock_bh(&ioat_chan->desc_lock);
if (append)
writeb(IOAT_CHANCMD_APPEND,
ioat_chan->reg_base + IOAT_CHANCMD_OFFSET);
return cookie;
}
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);
desc_sw->async_tx.tx_set_src = ioat_set_src;
desc_sw->async_tx.tx_set_dest = ioat_set_dest;
desc_sw->async_tx.tx_submit = ioat_tx_submit;
INIT_LIST_HEAD(&desc_sw->async_tx.tx_list);
desc_sw->hw = desc;
desc_sw->async_tx.phys = phys;
return desc_sw;
}
/* returns the actual number of allocated descriptors */
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 = NULL;
u16 chanctrl;
u32 chanerr;
int i;
LIST_HEAD(tmp_list);
/* have we already been set up? */
if (!list_empty(&ioat_chan->free_desc))
return INITIAL_IOAT_DESC_COUNT;
/* 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,
"ioatdma: CHANERR = %x, clearing\n", chanerr);
writel(chanerr, ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
}
/* Allocate descriptors */
for (i = 0; i < INITIAL_IOAT_DESC_COUNT; i++) {
desc = ioat_dma_alloc_descriptor(ioat_chan, GFP_KERNEL);
if (!desc) {
dev_err(&ioat_chan->device->pdev->dev,
"ioatdma: Only %d initial descriptors\n", i);
break;
}
list_add_tail(&desc->node, &tmp_list);
}
spin_lock_bh(&ioat_chan->desc_lock);
list_splice(&tmp_list, &ioat_chan->free_desc);
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);
return i;
}
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;
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);
mdelay(100);
spin_lock_bh(&ioat_chan->desc_lock);
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);
}
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,
"ioatdma: Freeing %d in use descriptors!\n",
in_use_descs - 1);
ioat_chan->last_completion = ioat_chan->completion_addr = 0;
ioat_chan->pending = 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 *ioat_dma_get_next_descriptor(
struct ioat_dma_chan *ioat_chan)
{
struct ioat_desc_sw *new = NULL;
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);
/* will this ever happen? */
/* TODO add upper limit on these */
BUG_ON(!new);
}
prefetch(new->hw);
return new;
}
static struct dma_async_tx_descriptor *ioat_dma_prep_memcpy(
struct dma_chan *chan,
size_t len,
int int_en)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
struct ioat_desc_sw *first, *prev, *new;
LIST_HEAD(new_chain);
u32 copy;
size_t orig_len;
int desc_count = 0;
if (!len)
return NULL;
orig_len = len;
first = NULL;
prev = NULL;
spin_lock_bh(&ioat_chan->desc_lock);
while (len) {
new = ioat_dma_get_next_descriptor(ioat_chan);
copy = min((u32) len, ioat_chan->xfercap);
new->hw->size = copy;
new->hw->ctl = 0;
new->async_tx.cookie = 0;
new->async_tx.ack = 1;
/* chain together the physical address list for the HW */
if (!first)
first = new;
else
prev->hw->next = (u64) new->async_tx.phys;
prev = new;
len -= copy;
list_add_tail(&new->node, &new_chain);
desc_count++;
}
list_splice(&new_chain, &new->async_tx.tx_list);
new->hw->ctl = IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
new->hw->next = 0;
new->tx_cnt = desc_count;
new->async_tx.ack = 0; /* client is in control of this ack */
new->async_tx.cookie = -EBUSY;
pci_unmap_len_set(new, len, orig_len);
spin_unlock_bh(&ioat_chan->desc_lock);
return new ? &new->async_tx : NULL;
}
/**
* ioat_dma_memcpy_issue_pending - push potentially unrecognized appended
* descriptors to hw
* @chan: DMA channel handle
*/
static void ioat_dma_memcpy_issue_pending(struct dma_chan *chan)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
if (ioat_chan->pending != 0) {
ioat_chan->pending = 0;
writeb(IOAT_CHANCMD_APPEND,
ioat_chan->reg_base + IOAT_CHANCMD_OFFSET);
}
}
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_memcpy_cleanup(struct ioat_dma_chan *ioat_chan)
{
unsigned long phys_complete;
struct ioat_desc_sw *desc, *_desc;
dma_cookie_t cookie = 0;
prefetch(ioat_chan->completion_virt);
if (!spin_trylock(&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,
"ioatdma: 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(&ioat_chan->cleanup_lock);
return;
}
cookie = 0;
spin_lock_bh(&ioat_chan->desc_lock);
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;
/*
* yes we are unmapping both _page and _single alloc'd
* regions with unmap_page. Is this *really* that bad?
*/
pci_unmap_page(ioat_chan->device->pdev,
pci_unmap_addr(desc, dst),
pci_unmap_len(desc, len),
PCI_DMA_FROMDEVICE);
pci_unmap_page(ioat_chan->device->pdev,
pci_unmap_addr(desc, src),
pci_unmap_len(desc, len),
PCI_DMA_TODEVICE);
}
if (desc->async_tx.phys != phys_complete) {
/*
* a completed entry, but not the last, so cleanup
* if the client is done with the descriptor
*/
if (desc->async_tx.ack) {
list_del(&desc->node);
list_add_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;
}
}
spin_unlock_bh(&ioat_chan->desc_lock);
ioat_chan->last_completion = phys_complete;
if (cookie != 0)
ioat_chan->completed_cookie = cookie;
spin_unlock(&ioat_chan->cleanup_lock);
}
static void ioat_dma_dependency_added(struct dma_chan *chan)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
spin_lock_bh(&ioat_chan->desc_lock);
if (ioat_chan->pending == 0) {
spin_unlock_bh(&ioat_chan->desc_lock);
ioat_dma_memcpy_cleanup(ioat_chan);
} else
spin_unlock_bh(&ioat_chan->desc_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;
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);
}
/* PCI API */
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);
desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL;
desc->hw->next = 0;
desc->async_tx.ack = 1;
list_add_tail(&desc->node, &ioat_chan->used_desc);
spin_unlock_bh(&ioat_chan->desc_lock);
writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
ioat_chan->reg_base + IOAT_CHAINADDR_OFFSET_LOW);
writel(((u64) desc->async_tx.phys) >> 32,
ioat_chan->reg_base + IOAT_CHAINADDR_OFFSET_HIGH);
writeb(IOAT_CHANCMD_START, ioat_chan->reg_base + IOAT_CHANCMD_OFFSET);
}
/*
* Perform a IOAT transaction to verify the HW works.
*/
#define IOAT_TEST_SIZE 2000
/**
* 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 addr;
dma_cookie_t cookie;
int err = 0;
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 (ioat_dma_alloc_chan_resources(dma_chan) < 1) {
dev_err(&device->pdev->dev,
"selftest cannot allocate chan resource\n");
err = -ENODEV;
goto out;
}
tx = ioat_dma_prep_memcpy(dma_chan, IOAT_TEST_SIZE, 0);
async_tx_ack(tx);
addr = dma_map_single(dma_chan->device->dev, src, IOAT_TEST_SIZE,
DMA_TO_DEVICE);
ioat_set_src(addr, tx, 0);
addr = dma_map_single(dma_chan->device->dev, dest, IOAT_TEST_SIZE,
DMA_FROM_DEVICE);
ioat_set_dest(addr, tx, 0);
cookie = ioat_tx_submit(tx);
ioat_dma_memcpy_issue_pending(dma_chan);
msleep(1);
if (ioat_dma_is_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) {
dev_err(&device->pdev->dev,
"ioatdma: Self-test copy timed out, disabling\n");
err = -ENODEV;
goto free_resources;
}
if (memcmp(src, dest, IOAT_TEST_SIZE)) {
dev_err(&device->pdev->dev,
"ioatdma: Self-test copy failed compare, disabling\n");
err = -ENODEV;
goto free_resources;
}
free_resources:
ioat_dma_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;
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);
dma_cap_set(DMA_MEMCPY, device->common.cap_mask);
device->common.device_alloc_chan_resources =
ioat_dma_alloc_chan_resources;
device->common.device_free_chan_resources =
ioat_dma_free_chan_resources;
device->common.device_prep_dma_memcpy = ioat_dma_prep_memcpy;
device->common.device_is_tx_complete = ioat_dma_is_complete;
device->common.device_issue_pending = ioat_dma_memcpy_issue_pending;
device->common.device_dependency_added = ioat_dma_dependency_added;
device->common.dev = &pdev->dev;
dev_err(&device->pdev->dev,
"ioatdma: Intel(R) I/OAT DMA Engine found,"
" %d channels, device version 0x%02x\n",
device->common.chancnt, device->version);
err = ioat_dma_setup_interrupts(device);
if (err)
goto err_setup_interrupts;
err = ioat_dma_self_test(device);
if (err)
goto err_self_test;
dma_async_device_register(&device->common);
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:
iounmap(iobase);
dev_err(&device->pdev->dev,
"ioatdma: 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;
dma_async_device_unregister(&device->common);
ioat_dma_remove_interrupts(device);
pci_pool_destroy(device->dma_pool);
pci_pool_destroy(device->completion_pool);
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);
}