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authorChris Leech <christopher.leech@intel.com>2006-05-23 17:35:34 -0700
committerDavid S. Miller <davem@sunset.davemloft.net>2006-06-17 21:18:46 -0700
commit0bbd5f4e97ff9c057b385a1886b4aed1fb0300f1 (patch)
tree0c3d8528c31e8291fb78c2e7a287910987ed2888 /drivers/dma/ioatdma.c
parentc13c8260da3155f2cefb63b0d1b7dcdcb405c644 (diff)
downloadop-kernel-dev-0bbd5f4e97ff9c057b385a1886b4aed1fb0300f1.zip
op-kernel-dev-0bbd5f4e97ff9c057b385a1886b4aed1fb0300f1.tar.gz
[I/OAT]: Driver for the Intel(R) I/OAT DMA engine
Adds a new ioatdma driver Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/dma/ioatdma.c')
-rw-r--r--drivers/dma/ioatdma.c839
1 files changed, 839 insertions, 0 deletions
diff --git a/drivers/dma/ioatdma.c b/drivers/dma/ioatdma.c
new file mode 100644
index 0000000..11d48b97
--- /dev/null
+++ b/drivers/dma/ioatdma.c
@@ -0,0 +1,839 @@
+/*
+ * Copyright(c) 2004 - 2006 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * 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., 59
+ * Temple Place - Suite 330, Boston, MA 02111-1307, 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 "ioatdma.h"
+#include "ioatdma_io.h"
+#include "ioatdma_registers.h"
+#include "ioatdma_hw.h"
+
+#define to_ioat_chan(chan) container_of(chan, struct ioat_dma_chan, common)
+#define to_ioat_device(dev) container_of(dev, struct ioat_device, common)
+#define to_ioat_desc(lh) container_of(lh, struct ioat_desc_sw, node)
+
+/* internal functions */
+static int __devinit ioat_probe(struct pci_dev *pdev, const struct pci_device_id *ent);
+static void __devexit ioat_remove(struct pci_dev *pdev);
+
+static int enumerate_dma_channels(struct ioat_device *device)
+{
+ u8 xfercap_scale;
+ u32 xfercap;
+ int i;
+ struct ioat_dma_chan *ioat_chan;
+
+ device->common.chancnt = ioatdma_read8(device, IOAT_CHANCNT_OFFSET);
+ xfercap_scale = ioatdma_read8(device, 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;
+ ioat_chan->common.client = NULL;
+ list_add_tail(&ioat_chan->common.device_node,
+ &device->common.channels);
+ }
+ return device->common.chancnt;
+}
+
+static struct ioat_desc_sw *ioat_dma_alloc_descriptor(
+ struct ioat_dma_chan *ioat_chan,
+ int flags)
+{
+ struct ioat_dma_descriptor *desc;
+ struct ioat_desc_sw *desc_sw;
+ struct ioat_device *ioat_device;
+ dma_addr_t phys;
+
+ ioat_device = to_ioat_device(ioat_chan->common.device);
+ desc = pci_pool_alloc(ioat_device->dma_pool, flags, &phys);
+ if (unlikely(!desc))
+ return NULL;
+
+ desc_sw = kzalloc(sizeof(*desc_sw), flags);
+ if (unlikely(!desc_sw)) {
+ pci_pool_free(ioat_device->dma_pool, desc, phys);
+ return NULL;
+ }
+
+ memset(desc, 0, sizeof(*desc));
+ desc_sw->hw = desc;
+ desc_sw->phys = phys;
+
+ return desc_sw;
+}
+
+#define INITIAL_IOAT_DESC_COUNT 128
+
+static void ioat_start_null_desc(struct ioat_dma_chan *ioat_chan);
+
+/* 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);
+
+ /*
+ * In-use bit automatically set by reading chanctrl
+ * If 0, we got it, if 1, someone else did
+ */
+ chanctrl = ioatdma_chan_read16(ioat_chan, IOAT_CHANCTRL_OFFSET);
+ if (chanctrl & IOAT_CHANCTRL_CHANNEL_IN_USE)
+ return -EBUSY;
+
+ /* Setup register to interrupt and write completion status on error */
+ chanctrl = IOAT_CHANCTRL_CHANNEL_IN_USE |
+ IOAT_CHANCTRL_ERR_INT_EN |
+ IOAT_CHANCTRL_ANY_ERR_ABORT_EN |
+ IOAT_CHANCTRL_ERR_COMPLETION_EN;
+ ioatdma_chan_write16(ioat_chan, IOAT_CHANCTRL_OFFSET, chanctrl);
+
+ chanerr = ioatdma_chan_read32(ioat_chan, IOAT_CHANERR_OFFSET);
+ if (chanerr) {
+ printk("IOAT: CHANERR = %x, clearing\n", chanerr);
+ ioatdma_chan_write32(ioat_chan, IOAT_CHANERR_OFFSET, chanerr);
+ }
+
+ /* Allocate descriptors */
+ for (i = 0; i < INITIAL_IOAT_DESC_COUNT; i++) {
+ desc = ioat_dma_alloc_descriptor(ioat_chan, GFP_KERNEL);
+ if (!desc) {
+ printk(KERN_ERR "IOAT: 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));
+ ioatdma_chan_write32(ioat_chan, IOAT_CHANCMP_OFFSET_LOW,
+ ((u64) ioat_chan->completion_addr) & 0x00000000FFFFFFFF);
+ ioatdma_chan_write32(ioat_chan, IOAT_CHANCMP_OFFSET_HIGH,
+ ((u64) ioat_chan->completion_addr) >> 32);
+
+ ioat_start_null_desc(ioat_chan);
+ return i;
+}
+
+static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan);
+
+static void ioat_dma_free_chan_resources(struct dma_chan *chan)
+{
+ struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
+ struct ioat_device *ioat_device = to_ioat_device(chan->device);
+ struct ioat_desc_sw *desc, *_desc;
+ u16 chanctrl;
+ int in_use_descs = 0;
+
+ ioat_dma_memcpy_cleanup(ioat_chan);
+
+ ioatdma_chan_write8(ioat_chan, IOAT_CHANCMD_OFFSET, IOAT_CHANCMD_RESET);
+
+ 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(ioat_device->dma_pool, desc->hw, desc->phys);
+ kfree(desc);
+ }
+ list_for_each_entry_safe(desc, _desc, &ioat_chan->free_desc, node) {
+ list_del(&desc->node);
+ pci_pool_free(ioat_device->dma_pool, desc->hw, desc->phys);
+ kfree(desc);
+ }
+ spin_unlock_bh(&ioat_chan->desc_lock);
+
+ pci_pool_free(ioat_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)
+ printk(KERN_ERR "IOAT: Freeing %d in use descriptors!\n",
+ in_use_descs - 1);
+
+ ioat_chan->last_completion = ioat_chan->completion_addr = 0;
+
+ /* Tell hw the chan is free */
+ chanctrl = ioatdma_chan_read16(ioat_chan, IOAT_CHANCTRL_OFFSET);
+ chanctrl &= ~IOAT_CHANCTRL_CHANNEL_IN_USE;
+ ioatdma_chan_write16(ioat_chan, IOAT_CHANCTRL_OFFSET, chanctrl);
+}
+
+/**
+ * do_ioat_dma_memcpy - actual function that initiates a IOAT DMA transaction
+ * @chan: IOAT DMA channel handle
+ * @dest: DMA destination address
+ * @src: DMA source address
+ * @len: transaction length in bytes
+ */
+
+static dma_cookie_t do_ioat_dma_memcpy(struct ioat_dma_chan *ioat_chan,
+ dma_addr_t dest,
+ dma_addr_t src,
+ size_t len)
+{
+ struct ioat_desc_sw *first;
+ struct ioat_desc_sw *prev;
+ struct ioat_desc_sw *new;
+ dma_cookie_t cookie;
+ LIST_HEAD(new_chain);
+ u32 copy;
+ size_t orig_len;
+ dma_addr_t orig_src, orig_dst;
+ unsigned int desc_count = 0;
+ unsigned int append = 0;
+
+ if (!ioat_chan || !dest || !src)
+ return -EFAULT;
+
+ if (!len)
+ return ioat_chan->common.cookie;
+
+ orig_len = len;
+ orig_src = src;
+ orig_dst = dest;
+
+ first = NULL;
+ prev = NULL;
+
+ spin_lock_bh(&ioat_chan->desc_lock);
+
+ while (len) {
+ 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);
+ }
+
+ copy = min((u32) len, ioat_chan->xfercap);
+
+ new->hw->size = copy;
+ new->hw->ctl = 0;
+ new->hw->src_addr = src;
+ new->hw->dst_addr = dest;
+ new->cookie = 0;
+
+ /* chain together the physical address list for the HW */
+ if (!first)
+ first = new;
+ else
+ prev->hw->next = (u64) new->phys;
+
+ prev = new;
+
+ len -= copy;
+ dest += copy;
+ src += copy;
+
+ list_add_tail(&new->node, &new_chain);
+ desc_count++;
+ }
+ new->hw->ctl = IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
+ new->hw->next = 0;
+
+ /* 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->cookie = cookie;
+
+ pci_unmap_addr_set(new, src, orig_src);
+ pci_unmap_addr_set(new, dst, orig_dst);
+ pci_unmap_len_set(new, src_len, orig_len);
+ pci_unmap_len_set(new, dst_len, orig_len);
+
+ /* write address into NextDescriptor field of last desc in chain */
+ to_ioat_desc(ioat_chan->used_desc.prev)->hw->next = first->phys;
+ list_splice_init(&new_chain, ioat_chan->used_desc.prev);
+
+ ioat_chan->pending += desc_count;
+ if (ioat_chan->pending >= 20) {
+ append = 1;
+ ioat_chan->pending = 0;
+ }
+
+ spin_unlock_bh(&ioat_chan->desc_lock);
+
+ if (append)
+ ioatdma_chan_write8(ioat_chan,
+ IOAT_CHANCMD_OFFSET,
+ IOAT_CHANCMD_APPEND);
+ return cookie;
+}
+
+/**
+ * ioat_dma_memcpy_buf_to_buf - wrapper that takes src & dest bufs
+ * @chan: IOAT DMA channel handle
+ * @dest: DMA destination address
+ * @src: DMA source address
+ * @len: transaction length in bytes
+ */
+
+static dma_cookie_t ioat_dma_memcpy_buf_to_buf(struct dma_chan *chan,
+ void *dest,
+ void *src,
+ size_t len)
+{
+ dma_addr_t dest_addr;
+ dma_addr_t src_addr;
+ struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
+
+ dest_addr = pci_map_single(ioat_chan->device->pdev,
+ dest, len, PCI_DMA_FROMDEVICE);
+ src_addr = pci_map_single(ioat_chan->device->pdev,
+ src, len, PCI_DMA_TODEVICE);
+
+ return do_ioat_dma_memcpy(ioat_chan, dest_addr, src_addr, len);
+}
+
+/**
+ * ioat_dma_memcpy_buf_to_pg - wrapper, copying from a buf to a page
+ * @chan: IOAT DMA channel handle
+ * @page: pointer to the page to copy to
+ * @offset: offset into that page
+ * @src: DMA source address
+ * @len: transaction length in bytes
+ */
+
+static dma_cookie_t ioat_dma_memcpy_buf_to_pg(struct dma_chan *chan,
+ struct page *page,
+ unsigned int offset,
+ void *src,
+ size_t len)
+{
+ dma_addr_t dest_addr;
+ dma_addr_t src_addr;
+ struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
+
+ dest_addr = pci_map_page(ioat_chan->device->pdev,
+ page, offset, len, PCI_DMA_FROMDEVICE);
+ src_addr = pci_map_single(ioat_chan->device->pdev,
+ src, len, PCI_DMA_TODEVICE);
+
+ return do_ioat_dma_memcpy(ioat_chan, dest_addr, src_addr, len);
+}
+
+/**
+ * ioat_dma_memcpy_pg_to_pg - wrapper, copying between two pages
+ * @chan: IOAT DMA channel handle
+ * @dest_pg: pointer to the page to copy to
+ * @dest_off: offset into that page
+ * @src_pg: pointer to the page to copy from
+ * @src_off: offset into that page
+ * @len: transaction length in bytes. This is guaranteed to not make a copy
+ * across a page boundary.
+ */
+
+static dma_cookie_t ioat_dma_memcpy_pg_to_pg(struct dma_chan *chan,
+ struct page *dest_pg,
+ unsigned int dest_off,
+ struct page *src_pg,
+ unsigned int src_off,
+ size_t len)
+{
+ dma_addr_t dest_addr;
+ dma_addr_t src_addr;
+ struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
+
+ dest_addr = pci_map_page(ioat_chan->device->pdev,
+ dest_pg, dest_off, len, PCI_DMA_FROMDEVICE);
+ src_addr = pci_map_page(ioat_chan->device->pdev,
+ src_pg, src_off, len, PCI_DMA_TODEVICE);
+
+ return do_ioat_dma_memcpy(ioat_chan, dest_addr, src_addr, len);
+}
+
+/**
+ * ioat_dma_memcpy_issue_pending - push potentially unrecognoized 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;
+ ioatdma_chan_write8(ioat_chan,
+ IOAT_CHANCMD_OFFSET,
+ IOAT_CHANCMD_APPEND);
+ }
+}
+
+static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *chan)
+{
+ unsigned long phys_complete;
+ struct ioat_desc_sw *desc, *_desc;
+ dma_cookie_t cookie = 0;
+
+ prefetch(chan->completion_virt);
+
+ if (!spin_trylock(&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 =
+ chan->completion_virt->full & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
+#else
+ phys_complete = chan->completion_virt->low & IOAT_LOW_COMPLETION_MASK;
+#endif
+
+ if ((chan->completion_virt->full & IOAT_CHANSTS_DMA_TRANSFER_STATUS) ==
+ IOAT_CHANSTS_DMA_TRANSFER_STATUS_HALTED) {
+ printk("IOAT: Channel halted, chanerr = %x\n",
+ ioatdma_chan_read32(chan, IOAT_CHANERR_OFFSET));
+
+ /* TODO do something to salvage the situation */
+ }
+
+ if (phys_complete == chan->last_completion) {
+ spin_unlock(&chan->cleanup_lock);
+ return;
+ }
+
+ spin_lock_bh(&chan->desc_lock);
+ list_for_each_entry_safe(desc, _desc, &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->cookie) {
+ cookie = desc->cookie;
+
+ /* yes we are unmapping both _page and _single alloc'd
+ regions with unmap_page. Is this *really* that bad?
+ */
+ pci_unmap_page(chan->device->pdev,
+ pci_unmap_addr(desc, dst),
+ pci_unmap_len(desc, dst_len),
+ PCI_DMA_FROMDEVICE);
+ pci_unmap_page(chan->device->pdev,
+ pci_unmap_addr(desc, src),
+ pci_unmap_len(desc, src_len),
+ PCI_DMA_TODEVICE);
+ }
+
+ if (desc->phys != phys_complete) {
+ /* a completed entry, but not the last, so cleanup */
+ list_del(&desc->node);
+ list_add_tail(&desc->node, &chan->free_desc);
+ } else {
+ /* last used desc. Do not remove, so we can append from
+ it, but don't look at it next time, either */
+ desc->cookie = 0;
+
+ /* TODO check status bits? */
+ break;
+ }
+ }
+
+ spin_unlock_bh(&chan->desc_lock);
+
+ chan->last_completion = phys_complete;
+ if (cookie != 0)
+ chan->completed_cookie = cookie;
+
+ spin_unlock(&chan->cleanup_lock);
+}
+
+/**
+ * ioat_dma_is_complete - poll the status of a IOAT DMA transaction
+ * @chan: IOAT DMA channel handle
+ * @cookie: DMA transaction identifier
+ */
+
+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 struct pci_device_id ioat_pci_tbl[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT) },
+ { 0, }
+};
+
+static struct pci_driver ioat_pci_drv = {
+ .name = "ioatdma",
+ .id_table = ioat_pci_tbl,
+ .probe = ioat_probe,
+ .remove = __devexit_p(ioat_remove),
+};
+
+static irqreturn_t ioat_do_interrupt(int irq, void *data, struct pt_regs *regs)
+{
+ struct ioat_device *instance = data;
+ unsigned long attnstatus;
+ u8 intrctrl;
+
+ intrctrl = ioatdma_read8(instance, IOAT_INTRCTRL_OFFSET);
+
+ if (!(intrctrl & IOAT_INTRCTRL_MASTER_INT_EN))
+ return IRQ_NONE;
+
+ if (!(intrctrl & IOAT_INTRCTRL_INT_STATUS)) {
+ ioatdma_write8(instance, IOAT_INTRCTRL_OFFSET, intrctrl);
+ return IRQ_NONE;
+ }
+
+ attnstatus = ioatdma_read32(instance, IOAT_ATTNSTATUS_OFFSET);
+
+ printk(KERN_ERR "ioatdma error: interrupt! status %lx\n", attnstatus);
+
+ ioatdma_write8(instance, IOAT_INTRCTRL_OFFSET, intrctrl);
+ return IRQ_HANDLED;
+}
+
+static void ioat_start_null_desc(struct ioat_dma_chan *ioat_chan)
+{
+ struct ioat_desc_sw *desc;
+
+ spin_lock_bh(&ioat_chan->desc_lock);
+
+ if (!list_empty(&ioat_chan->free_desc)) {
+ desc = to_ioat_desc(ioat_chan->free_desc.next);
+ list_del(&desc->node);
+ } else {
+ /* try to get another desc */
+ spin_unlock_bh(&ioat_chan->desc_lock);
+ desc = ioat_dma_alloc_descriptor(ioat_chan, GFP_KERNEL);
+ spin_lock_bh(&ioat_chan->desc_lock);
+ /* will this ever happen? */
+ BUG_ON(!desc);
+ }
+
+ desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL;
+ desc->hw->next = 0;
+
+ list_add_tail(&desc->node, &ioat_chan->used_desc);
+ spin_unlock_bh(&ioat_chan->desc_lock);
+
+#if (BITS_PER_LONG == 64)
+ ioatdma_chan_write64(ioat_chan, IOAT_CHAINADDR_OFFSET, desc->phys);
+#else
+ ioatdma_chan_write32(ioat_chan,
+ IOAT_CHAINADDR_OFFSET_LOW,
+ (u32) desc->phys);
+ ioatdma_chan_write32(ioat_chan, IOAT_CHAINADDR_OFFSET_HIGH, 0);
+#endif
+ ioatdma_chan_write8(ioat_chan, IOAT_CHANCMD_OFFSET, IOAT_CHANCMD_START);
+}
+
+/*
+ * Perform a IOAT transaction to verify the HW works.
+ */
+#define IOAT_TEST_SIZE 2000
+
+static int ioat_self_test(struct ioat_device *device)
+{
+ int i;
+ u8 *src;
+ u8 *dest;
+ struct dma_chan *dma_chan;
+ dma_cookie_t cookie;
+ int err = 0;
+
+ src = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, SLAB_KERNEL);
+ if (!src)
+ return -ENOMEM;
+ dest = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, SLAB_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) {
+ err = -ENODEV;
+ goto out;
+ }
+
+ cookie = ioat_dma_memcpy_buf_to_buf(dma_chan, dest, src, IOAT_TEST_SIZE);
+ ioat_dma_memcpy_issue_pending(dma_chan);
+ msleep(1);
+
+ if (ioat_dma_is_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) {
+ printk(KERN_ERR "ioatdma: Self-test copy timed out, disabling\n");
+ err = -ENODEV;
+ goto free_resources;
+ }
+ if (memcmp(src, dest, IOAT_TEST_SIZE)) {
+ printk(KERN_ERR "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 int __devinit ioat_probe(struct pci_dev *pdev,
+ const struct pci_device_id *ent)
+{
+ int err;
+ unsigned long mmio_start, mmio_len;
+ void *reg_base;
+ struct ioat_device *device;
+
+ err = pci_enable_device(pdev);
+ if (err)
+ goto err_enable_device;
+
+ err = pci_set_dma_mask(pdev, DMA_64BIT_MASK);
+ if (err)
+ err = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
+ if (err)
+ goto err_set_dma_mask;
+
+ err = pci_request_regions(pdev, ioat_pci_drv.name);
+ if (err)
+ goto err_request_regions;
+
+ mmio_start = pci_resource_start(pdev, 0);
+ mmio_len = pci_resource_len(pdev, 0);
+
+ reg_base = ioremap(mmio_start, mmio_len);
+ if (!reg_base) {
+ err = -ENOMEM;
+ goto err_ioremap;
+ }
+
+ device = kzalloc(sizeof(*device), GFP_KERNEL);
+ if (!device) {
+ err = -ENOMEM;
+ goto err_kzalloc;
+ }
+
+ /* 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;
+ }
+
+ device->pdev = pdev;
+ pci_set_drvdata(pdev, device);
+#ifdef CONFIG_PCI_MSI
+ if (pci_enable_msi(pdev) == 0) {
+ device->msi = 1;
+ } else {
+ device->msi = 0;
+ }
+#endif
+ err = request_irq(pdev->irq, &ioat_do_interrupt, SA_SHIRQ, "ioat",
+ device);
+ if (err)
+ goto err_irq;
+
+ device->reg_base = reg_base;
+
+ ioatdma_write8(device, IOAT_INTRCTRL_OFFSET, IOAT_INTRCTRL_MASTER_INT_EN);
+ pci_set_master(pdev);
+
+ INIT_LIST_HEAD(&device->common.channels);
+ enumerate_dma_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.device_memcpy_buf_to_buf = ioat_dma_memcpy_buf_to_buf;
+ device->common.device_memcpy_buf_to_pg = ioat_dma_memcpy_buf_to_pg;
+ device->common.device_memcpy_pg_to_pg = ioat_dma_memcpy_pg_to_pg;
+ device->common.device_memcpy_complete = ioat_dma_is_complete;
+ device->common.device_memcpy_issue_pending = ioat_dma_memcpy_issue_pending;
+ printk(KERN_INFO "Intel(R) I/OAT DMA Engine found, %d channels\n",
+ device->common.chancnt);
+
+ err = ioat_self_test(device);
+ if (err)
+ goto err_self_test;
+
+ dma_async_device_register(&device->common);
+
+ return 0;
+
+err_self_test:
+err_irq:
+ pci_pool_destroy(device->completion_pool);
+err_completion_pool:
+ pci_pool_destroy(device->dma_pool);
+err_dma_pool:
+ kfree(device);
+err_kzalloc:
+ iounmap(reg_base);
+err_ioremap:
+ pci_release_regions(pdev);
+err_request_regions:
+err_set_dma_mask:
+ pci_disable_device(pdev);
+err_enable_device:
+ return err;
+}
+
+static void __devexit ioat_remove(struct pci_dev *pdev)
+{
+ struct ioat_device *device;
+ struct dma_chan *chan, *_chan;
+ struct ioat_dma_chan *ioat_chan;
+
+ device = pci_get_drvdata(pdev);
+ dma_async_device_unregister(&device->common);
+
+ free_irq(device->pdev->irq, device);
+#ifdef CONFIG_PCI_MSI
+ if (device->msi)
+ pci_disable_msi(device->pdev);
+#endif
+ pci_pool_destroy(device->dma_pool);
+ pci_pool_destroy(device->completion_pool);
+ iounmap(device->reg_base);
+ pci_release_regions(pdev);
+ pci_disable_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);
+}
+
+/* MODULE API */
+MODULE_VERSION("1.7");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Intel Corporation");
+
+static int __init ioat_init_module(void)
+{
+ /* it's currently unsafe to unload this module */
+ /* if forced, worst case is that rmmod hangs */
+ if (THIS_MODULE != NULL)
+ THIS_MODULE->unsafe = 1;
+
+ return pci_module_init(&ioat_pci_drv);
+}
+
+module_init(ioat_init_module);
+
+static void __exit ioat_exit_module(void)
+{
+ pci_unregister_driver(&ioat_pci_drv);
+}
+
+module_exit(ioat_exit_module);
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