--- /dev/null
+/*
+ * 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.
+ *
+ * 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/slab.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/prefetch.h>
+#include <linux/i7300_idle.h>
+#include "dma.h"
+#include "registers.h"
+#include "hw.h"
+
+#include "../dmaengine.h"
+
+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)");
+
+/* internal functions */
+static void ioat1_cleanup(struct ioat_dma_chan *ioat);
+static void ioat1_dma_start_null_desc(struct ioat_dma_chan *ioat);
+
+/**
+ * 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_chan_common *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_set_bit(bit, &attnstatus, BITS_PER_LONG) {
+ chan = ioat_chan_by_index(instance, bit);
+ if (test_bit(IOAT_RUN, &chan->state))
+ tasklet_schedule(&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_chan_common *chan = data;
+
+ if (test_bit(IOAT_RUN, &chan->state))
+ tasklet_schedule(&chan->cleanup_task);
+
+ return IRQ_HANDLED;
+}
+
+/* common channel initialization */
+void ioat_init_channel(struct ioatdma_device *device, struct ioat_chan_common *chan, int idx)
+{
+ struct dma_device *dma = &device->common;
+ struct dma_chan *c = &chan->common;
+ unsigned long data = (unsigned long) c;
+
+ chan->device = device;
+ chan->reg_base = device->reg_base + (0x80 * (idx + 1));
+ spin_lock_init(&chan->cleanup_lock);
+ chan->common.device = dma;
+ dma_cookie_init(&chan->common);
+ list_add_tail(&chan->common.device_node, &dma->channels);
+ device->idx[idx] = chan;
+ init_timer(&chan->timer);
+ chan->timer.function = device->timer_fn;
+ chan->timer.data = data;
+ tasklet_init(&chan->cleanup_task, device->cleanup_fn, data);
+}
+
+/**
+ * ioat1_dma_enumerate_channels - find and initialize the device's channels
+ * @device: the device to be enumerated
+ */
+static int ioat1_enumerate_channels(struct ioatdma_device *device)
+{
+ u8 xfercap_scale;
+ u32 xfercap;
+ int i;
+ struct ioat_dma_chan *ioat;
+ struct device *dev = &device->pdev->dev;
+ struct dma_device *dma = &device->common;
+
+ INIT_LIST_HEAD(&dma->channels);
+ dma->chancnt = readb(device->reg_base + IOAT_CHANCNT_OFFSET);
+ dma->chancnt &= 0x1f; /* bits [4:0] valid */
+ if (dma->chancnt > ARRAY_SIZE(device->idx)) {
+ dev_warn(dev, "(%d) exceeds max supported channels (%zu)\n",
+ dma->chancnt, ARRAY_SIZE(device->idx));
+ dma->chancnt = ARRAY_SIZE(device->idx);
+ }
+ xfercap_scale = readb(device->reg_base + IOAT_XFERCAP_OFFSET);
+ xfercap_scale &= 0x1f; /* bits [4:0] valid */
+ xfercap = (xfercap_scale == 0 ? -1 : (1UL << xfercap_scale));
+ dev_dbg(dev, "%s: xfercap = %d\n", __func__, xfercap);
+
+#ifdef CONFIG_I7300_IDLE_IOAT_CHANNEL
+ if (i7300_idle_platform_probe(NULL, NULL, 1) == 0)
+ dma->chancnt--;
+#endif
+ for (i = 0; i < dma->chancnt; i++) {
+ ioat = devm_kzalloc(dev, sizeof(*ioat), GFP_KERNEL);
+ if (!ioat)
+ break;
+
+ ioat_init_channel(device, &ioat->base, i);
+ ioat->xfercap = xfercap;
+ spin_lock_init(&ioat->desc_lock);
+ INIT_LIST_HEAD(&ioat->free_desc);
+ INIT_LIST_HEAD(&ioat->used_desc);
+ }
+ dma->chancnt = i;
+ return i;
+}
+
+/**
+ * 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)
+{
+ void __iomem *reg_base = ioat->base.reg_base;
+
+ dev_dbg(to_dev(&ioat->base), "%s: pending: %d\n",
+ __func__, ioat->pending);
+ ioat->pending = 0;
+ writeb(IOAT_CHANCMD_APPEND, reg_base + IOAT1_CHANCMD_OFFSET);
+}
+
+static void ioat1_dma_memcpy_issue_pending(struct dma_chan *chan)
+{
+ struct ioat_dma_chan *ioat = to_ioat_chan(chan);
+
+ if (ioat->pending > 0) {
+ spin_lock_bh(&ioat->desc_lock);
+ __ioat1_dma_memcpy_issue_pending(ioat);
+ spin_unlock_bh(&ioat->desc_lock);
+ }
+}
+
+/**
+ * ioat1_reset_channel - restart a channel
+ * @ioat: IOAT DMA channel handle
+ */
+static void ioat1_reset_channel(struct ioat_dma_chan *ioat)
+{
+ struct ioat_chan_common *chan = &ioat->base;
+ void __iomem *reg_base = chan->reg_base;
+ u32 chansts, chanerr;
+
+ dev_warn(to_dev(chan), "reset\n");
+ chanerr = readl(reg_base + IOAT_CHANERR_OFFSET);
+ chansts = *chan->completion & IOAT_CHANSTS_STATUS;
+ if (chanerr) {
+ dev_err(to_dev(chan),
+ "chan%d, CHANSTS = 0x%08x CHANERR = 0x%04x, clearing\n",
+ chan_num(chan), chansts, chanerr);
+ writel(chanerr, 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.
+ */
+
+ ioat->pending = INT_MIN;
+ writeb(IOAT_CHANCMD_RESET,
+ reg_base + IOAT_CHANCMD_OFFSET(chan->device->version));
+ set_bit(IOAT_RESET_PENDING, &chan->state);
+ mod_timer(&chan->timer, jiffies + RESET_DELAY);
+}
+
+static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
+{
+ struct dma_chan *c = tx->chan;
+ struct ioat_dma_chan *ioat = to_ioat_chan(c);
+ struct ioat_desc_sw *desc = tx_to_ioat_desc(tx);
+ struct ioat_chan_common *chan = &ioat->base;
+ struct ioat_desc_sw *first;
+ struct ioat_desc_sw *chain_tail;
+ dma_cookie_t cookie;
+
+ spin_lock_bh(&ioat->desc_lock);
+ /* cookie incr and addition to used_list must be atomic */
+ cookie = dma_cookie_assign(tx);
+ dev_dbg(to_dev(&ioat->base), "%s: cookie: %d\n", __func__, cookie);
+
+ /* write address into NextDescriptor field of last desc in chain */
+ first = to_ioat_desc(desc->tx_list.next);
+ chain_tail = to_ioat_desc(ioat->used_desc.prev);
+ /* make descriptor updates globally visible before chaining */
+ wmb();
+ chain_tail->hw->next = first->txd.phys;
+ list_splice_tail_init(&desc->tx_list, &ioat->used_desc);
+ dump_desc_dbg(ioat, chain_tail);
+ dump_desc_dbg(ioat, first);
+
+ if (!test_and_set_bit(IOAT_COMPLETION_PENDING, &chan->state))
+ mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT);
+
+ ioat->active += desc->hw->tx_cnt;
+ ioat->pending += desc->hw->tx_cnt;
+ if (ioat->pending >= ioat_pending_level)
+ __ioat1_dma_memcpy_issue_pending(ioat);
+ spin_unlock_bh(&ioat->desc_lock);
+
+ return cookie;
+}
+
+/**
+ * ioat_dma_alloc_descriptor - allocate and return a sw and hw descriptor pair
+ * @ioat: 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, 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 = ioat->base.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));
+
+ INIT_LIST_HEAD(&desc_sw->tx_list);
+ dma_async_tx_descriptor_init(&desc_sw->txd, &ioat->base.common);
+ desc_sw->txd.tx_submit = ioat1_tx_submit;
+ desc_sw->hw = desc;
+ desc_sw->txd.phys = phys;
+ set_desc_id(desc_sw, -1);
+
+ 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,
+ "ioat1: initial descriptors per channel (default: 256)");
+/**
+ * ioat1_dma_alloc_chan_resources - returns the number of allocated descriptors
+ * @chan: the channel to be filled out
+ */
+static int ioat1_dma_alloc_chan_resources(struct dma_chan *c)
+{
+ struct ioat_dma_chan *ioat = to_ioat_chan(c);
+ struct ioat_chan_common *chan = &ioat->base;
+ struct ioat_desc_sw *desc;
+ u32 chanerr;
+ int i;
+ LIST_HEAD(tmp_list);
+
+ /* have we already been set up? */
+ if (!list_empty(&ioat->free_desc))
+ return ioat->desccount;
+
+ /* Setup register to interrupt and write completion status on error */
+ writew(IOAT_CHANCTRL_RUN, chan->reg_base + IOAT_CHANCTRL_OFFSET);
+
+ chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
+ if (chanerr) {
+ dev_err(to_dev(chan), "CHANERR = %x, clearing\n", chanerr);
+ writel(chanerr, chan->reg_base + IOAT_CHANERR_OFFSET);
+ }
+
+ /* Allocate descriptors */
+ for (i = 0; i < ioat_initial_desc_count; i++) {
+ desc = ioat_dma_alloc_descriptor(ioat, GFP_KERNEL);
+ if (!desc) {
+ dev_err(to_dev(chan), "Only %d initial descriptors\n", i);
+ break;
+ }
+ set_desc_id(desc, i);
+ list_add_tail(&desc->node, &tmp_list);
+ }
+ spin_lock_bh(&ioat->desc_lock);
+ ioat->desccount = i;
+ list_splice(&tmp_list, &ioat->free_desc);
+ spin_unlock_bh(&ioat->desc_lock);
+
+ /* allocate a completion writeback area */
+ /* doing 2 32bit writes to mmio since 1 64b write doesn't work */
+ chan->completion = pci_pool_alloc(chan->device->completion_pool,
+ GFP_KERNEL, &chan->completion_dma);
+ memset(chan->completion, 0, sizeof(*chan->completion));
+ writel(((u64) chan->completion_dma) & 0x00000000FFFFFFFF,
+ chan->reg_base + IOAT_CHANCMP_OFFSET_LOW);
+ writel(((u64) chan->completion_dma) >> 32,
+ chan->reg_base + IOAT_CHANCMP_OFFSET_HIGH);
+
+ set_bit(IOAT_RUN, &chan->state);
+ ioat1_dma_start_null_desc(ioat); /* give chain to dma device */
+ dev_dbg(to_dev(chan), "%s: allocated %d descriptors\n",
+ __func__, ioat->desccount);
+ return ioat->desccount;
+}
+
+void ioat_stop(struct ioat_chan_common *chan)
+{
+ struct ioatdma_device *device = chan->device;
+ struct pci_dev *pdev = device->pdev;
+ int chan_id = chan_num(chan);
+ struct msix_entry *msix;
+
+ /* 1/ stop irq from firing tasklets
+ * 2/ stop the tasklet from re-arming irqs
+ */
+ clear_bit(IOAT_RUN, &chan->state);
+
+ /* flush inflight interrupts */
+ switch (device->irq_mode) {
+ case IOAT_MSIX:
+ msix = &device->msix_entries[chan_id];
+ synchronize_irq(msix->vector);
+ break;
+ case IOAT_MSI:
+ case IOAT_INTX:
+ synchronize_irq(pdev->irq);
+ break;
+ default:
+ break;
+ }
+
+ /* flush inflight timers */
+ del_timer_sync(&chan->timer);
+
+ /* flush inflight tasklet runs */
+ tasklet_kill(&chan->cleanup_task);
+
+ /* final cleanup now that everything is quiesced and can't re-arm */
+ device->cleanup_fn((unsigned long) &chan->common);
+}
+
+/**
+ * ioat1_dma_free_chan_resources - release all the descriptors
+ * @chan: the channel to be cleaned
+ */
+static void ioat1_dma_free_chan_resources(struct dma_chan *c)
+{
+ struct ioat_dma_chan *ioat = to_ioat_chan(c);
+ struct ioat_chan_common *chan = &ioat->base;
+ struct ioatdma_device *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->desccount == 0)
+ return;
+
+ ioat_stop(chan);
+
+ /* Delay 100ms after reset to allow internal DMA logic to quiesce
+ * before removing DMA descriptor resources.
+ */
+ writeb(IOAT_CHANCMD_RESET,
+ chan->reg_base + IOAT_CHANCMD_OFFSET(chan->device->version));
+ mdelay(100);
+
+ spin_lock_bh(&ioat->desc_lock);
+ list_for_each_entry_safe(desc, _desc, &ioat->used_desc, node) {
+ dev_dbg(to_dev(chan), "%s: freeing %d from used list\n",
+ __func__, desc_id(desc));
+ dump_desc_dbg(ioat, desc);
+ in_use_descs++;
+ list_del(&desc->node);
+ pci_pool_free(ioatdma_device->dma_pool, desc->hw,
+ desc->txd.phys);
+ kfree(desc);
+ }
+ list_for_each_entry_safe(desc, _desc,
+ &ioat->free_desc, node) {
+ list_del(&desc->node);
+ pci_pool_free(ioatdma_device->dma_pool, desc->hw,
+ desc->txd.phys);
+ kfree(desc);
+ }
+ spin_unlock_bh(&ioat->desc_lock);
+
+ pci_pool_free(ioatdma_device->completion_pool,
+ chan->completion,
+ chan->completion_dma);
+
+ /* one is ok since we left it on there on purpose */
+ if (in_use_descs > 1)
+ dev_err(to_dev(chan), "Freeing %d in use descriptors!\n",
+ in_use_descs - 1);
+
+ chan->last_completion = 0;
+ chan->completion_dma = 0;
+ ioat->pending = 0;
+ ioat->desccount = 0;
+}
+
+/**
+ * ioat1_dma_get_next_descriptor - return the next available descriptor
+ * @ioat: 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)
+{
+ struct ioat_desc_sw *new;
+
+ if (!list_empty(&ioat->free_desc)) {
+ new = to_ioat_desc(ioat->free_desc.next);
+ list_del(&new->node);
+ } else {
+ /* try to get another desc */
+ new = ioat_dma_alloc_descriptor(ioat, GFP_ATOMIC);
+ if (!new) {
+ dev_err(to_dev(&ioat->base), "alloc failed\n");
+ return NULL;
+ }
+ }
+ dev_dbg(to_dev(&ioat->base), "%s: allocated: %d\n",
+ __func__, desc_id(new));
+ prefetch(new->hw);
+ return new;
+}
+
+static struct dma_async_tx_descriptor *
+ioat1_dma_prep_memcpy(struct dma_chan *c, dma_addr_t dma_dest,
+ dma_addr_t dma_src, size_t len, unsigned long flags)
+{
+ struct ioat_dma_chan *ioat = to_ioat_chan(c);
+ struct ioat_desc_sw *desc;
+ size_t copy;
+ LIST_HEAD(chain);
+ dma_addr_t src = dma_src;
+ dma_addr_t dest = dma_dest;
+ size_t total_len = len;
+ struct ioat_dma_descriptor *hw = NULL;
+ int tx_cnt = 0;
+
+ spin_lock_bh(&ioat->desc_lock);
+ desc = ioat1_dma_get_next_descriptor(ioat);
+ do {
+ if (!desc)
+ break;
+
+ tx_cnt++;
+ copy = min_t(size_t, len, ioat->xfercap);
+
+ hw = desc->hw;
+ hw->size = copy;
+ hw->ctl = 0;
+ hw->src_addr = src;
+ hw->dst_addr = dest;
+
+ list_add_tail(&desc->node, &chain);
+
+ len -= copy;
+ dest += copy;
+ src += copy;
+ if (len) {
+ struct ioat_desc_sw *next;
+
+ async_tx_ack(&desc->txd);
+ next = ioat1_dma_get_next_descriptor(ioat);
+ hw->next = next ? next->txd.phys : 0;
+ dump_desc_dbg(ioat, desc);
+ desc = next;
+ } else
+ hw->next = 0;
+ } while (len);
+
+ if (!desc) {
+ struct ioat_chan_common *chan = &ioat->base;
+
+ dev_err(to_dev(chan),
+ "chan%d - get_next_desc failed\n", chan_num(chan));
+ list_splice(&chain, &ioat->free_desc);
+ spin_unlock_bh(&ioat->desc_lock);
+ return NULL;
+ }
+ spin_unlock_bh(&ioat->desc_lock);
+
+ desc->txd.flags = flags;
+ desc->len = total_len;
+ list_splice(&chain, &desc->tx_list);
+ hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT);
+ hw->ctl_f.compl_write = 1;
+ hw->tx_cnt = tx_cnt;
+ dump_desc_dbg(ioat, desc);
+
+ return &desc->txd;
+}
+
+static void ioat1_cleanup_event(unsigned long data)
+{
+ struct ioat_dma_chan *ioat = to_ioat_chan((void *) data);
+ struct ioat_chan_common *chan = &ioat->base;
+
+ ioat1_cleanup(ioat);
+ if (!test_bit(IOAT_RUN, &chan->state))
+ return;
+ writew(IOAT_CHANCTRL_RUN, ioat->base.reg_base + IOAT_CHANCTRL_OFFSET);
+}
+
+dma_addr_t ioat_get_current_completion(struct ioat_chan_common *chan)
+{
+ dma_addr_t phys_complete;
+ u64 completion;
+
+ completion = *chan->completion;
+ phys_complete = ioat_chansts_to_addr(completion);
+
+ dev_dbg(to_dev(chan), "%s: phys_complete: %#llx\n", __func__,
+ (unsigned long long) phys_complete);
+
+ if (is_ioat_halted(completion)) {
+ u32 chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
+ dev_err(to_dev(chan), "Channel halted, chanerr = %x\n",
+ chanerr);
+
+ /* TODO do something to salvage the situation */
+ }
+
+ return phys_complete;
+}
+
+bool ioat_cleanup_preamble(struct ioat_chan_common *chan,
+ dma_addr_t *phys_complete)
+{
+ *phys_complete = ioat_get_current_completion(chan);
+ if (*phys_complete == chan->last_completion)
+ return false;
+ clear_bit(IOAT_COMPLETION_ACK, &chan->state);
+ mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT);
+
+ return true;
+}
+
+static void __cleanup(struct ioat_dma_chan *ioat, dma_addr_t phys_complete)
+{
+ struct ioat_chan_common *chan = &ioat->base;
+ struct list_head *_desc, *n;
+ struct dma_async_tx_descriptor *tx;
+
+ dev_dbg(to_dev(chan), "%s: phys_complete: %llx\n",
+ __func__, (unsigned long long) phys_complete);
+ list_for_each_safe(_desc, n, &ioat->used_desc) {
+ struct ioat_desc_sw *desc;
+
+ prefetch(n);
+ desc = list_entry(_desc, typeof(*desc), node);
+ tx = &desc->txd;
+ /*
+ * 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.
+ */
+ dump_desc_dbg(ioat, desc);
+ if (tx->cookie) {
+ dma_cookie_complete(tx);
+ dma_descriptor_unmap(tx);
+ ioat->active -= desc->hw->tx_cnt;
+ if (tx->callback) {
+ tx->callback(tx->callback_param);
+ tx->callback = NULL;
+ }
+ }
+
+ if (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(tx))
+ list_move_tail(&desc->node, &ioat->free_desc);
+ } else {
+ /*
+ * last used desc. Do not remove, so we can
+ * append from it.
+ */
+
+ /* if nothing else is pending, cancel the
+ * completion timeout
+ */
+ if (n == &ioat->used_desc) {
+ dev_dbg(to_dev(chan),
+ "%s cancel completion timeout\n",
+ __func__);
+ clear_bit(IOAT_COMPLETION_PENDING, &chan->state);
+ }
+
+ /* TODO check status bits? */
+ break;
+ }
+ }
+
+ chan->last_completion = phys_complete;
+}
+
+/**
+ * ioat1_cleanup - cleanup up finished descriptors
+ * @chan: ioat channel to be cleaned up
+ *
+ * To prevent lock contention we defer cleanup when the locks are
+ * contended with a terminal timeout that forces cleanup and catches
+ * completion notification errors.
+ */
+static void ioat1_cleanup(struct ioat_dma_chan *ioat)
+{
+ struct ioat_chan_common *chan = &ioat->base;
+ dma_addr_t phys_complete;
+
+ prefetch(chan->completion);
+
+ if (!spin_trylock_bh(&chan->cleanup_lock))
+ return;
+
+ if (!ioat_cleanup_preamble(chan, &phys_complete)) {
+ spin_unlock_bh(&chan->cleanup_lock);
+ return;
+ }
+
+ if (!spin_trylock_bh(&ioat->desc_lock)) {
+ spin_unlock_bh(&chan->cleanup_lock);
+ return;
+ }
+
+ __cleanup(ioat, phys_complete);
+
+ spin_unlock_bh(&ioat->desc_lock);
+ spin_unlock_bh(&chan->cleanup_lock);
+}
+
+static void ioat1_timer_event(unsigned long data)
+{
+ struct ioat_dma_chan *ioat = to_ioat_chan((void *) data);
+ struct ioat_chan_common *chan = &ioat->base;
+
+ dev_dbg(to_dev(chan), "%s: state: %lx\n", __func__, chan->state);
+
+ spin_lock_bh(&chan->cleanup_lock);
+ if (test_and_clear_bit(IOAT_RESET_PENDING, &chan->state)) {
+ struct ioat_desc_sw *desc;
+
+ spin_lock_bh(&ioat->desc_lock);
+
+ /* restart active descriptors */
+ desc = to_ioat_desc(ioat->used_desc.prev);
+ ioat_set_chainaddr(ioat, desc->txd.phys);
+ ioat_start(chan);
+
+ ioat->pending = 0;
+ set_bit(IOAT_COMPLETION_PENDING, &chan->state);
+ mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT);
+ spin_unlock_bh(&ioat->desc_lock);
+ } else if (test_bit(IOAT_COMPLETION_PENDING, &chan->state)) {
+ dma_addr_t phys_complete;
+
+ spin_lock_bh(&ioat->desc_lock);
+ /* if we haven't made progress and we have already
+ * acknowledged a pending completion once, then be more
+ * forceful with a restart
+ */
+ if (ioat_cleanup_preamble(chan, &phys_complete))
+ __cleanup(ioat, phys_complete);
+ else if (test_bit(IOAT_COMPLETION_ACK, &chan->state))
+ ioat1_reset_channel(ioat);
+ else {
+ u64 status = ioat_chansts(chan);
+
+ /* manually update the last completion address */
+ if (ioat_chansts_to_addr(status) != 0)
+ *chan->completion = status;
+
+ set_bit(IOAT_COMPLETION_ACK, &chan->state);
+ mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT);
+ }
+ spin_unlock_bh(&ioat->desc_lock);
+ }
+ spin_unlock_bh(&chan->cleanup_lock);
+}
+
+enum dma_status
+ioat_dma_tx_status(struct dma_chan *c, dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct ioat_chan_common *chan = to_chan_common(c);
+ struct ioatdma_device *device = chan->device;
+ enum dma_status ret;
+
+ ret = dma_cookie_status(c, cookie, txstate);
+ if (ret == DMA_COMPLETE)
+ return ret;
+
+ device->cleanup_fn((unsigned long) c);
+
+ return dma_cookie_status(c, cookie, txstate);
+}
+
+static void ioat1_dma_start_null_desc(struct ioat_dma_chan *ioat)
+{
+ struct ioat_chan_common *chan = &ioat->base;
+ struct ioat_desc_sw *desc;
+ struct ioat_dma_descriptor *hw;
+
+ spin_lock_bh(&ioat->desc_lock);
+
+ desc = ioat1_dma_get_next_descriptor(ioat);
+
+ if (!desc) {
+ dev_err(to_dev(chan),
+ "Unable to start null desc - get next desc failed\n");
+ spin_unlock_bh(&ioat->desc_lock);
+ return;
+ }
+
+ hw = desc->hw;
+ hw->ctl = 0;
+ hw->ctl_f.null = 1;
+ hw->ctl_f.int_en = 1;
+ hw->ctl_f.compl_write = 1;
+ /* set size to non-zero value (channel returns error when size is 0) */
+ hw->size = NULL_DESC_BUFFER_SIZE;
+ hw->src_addr = 0;
+ hw->dst_addr = 0;
+ async_tx_ack(&desc->txd);
+ hw->next = 0;
+ list_add_tail(&desc->node, &ioat->used_desc);
+ dump_desc_dbg(ioat, desc);
+
+ ioat_set_chainaddr(ioat, desc->txd.phys);
+ ioat_start(chan);
+ spin_unlock_bh(&ioat->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
+ */
+int ioat_dma_self_test(struct ioatdma_device *device)
+{
+ int i;
+ u8 *src;
+ u8 *dest;
+ struct dma_device *dma = &device->common;
+ struct device *dev = &device->pdev->dev;
+ 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;
+ unsigned long flags;
+
+ 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(dma->channels.next, struct dma_chan,
+ device_node);
+ if (dma->device_alloc_chan_resources(dma_chan) < 1) {
+ dev_err(dev, "selftest cannot allocate chan resource\n");
+ err = -ENODEV;
+ goto out;
+ }
+
+ dma_src = dma_map_single(dev, src, IOAT_TEST_SIZE, DMA_TO_DEVICE);
+ if (dma_mapping_error(dev, dma_src)) {
+ dev_err(dev, "mapping src buffer failed\n");
+ goto free_resources;
+ }
+ dma_dest = dma_map_single(dev, dest, IOAT_TEST_SIZE, DMA_FROM_DEVICE);
+ if (dma_mapping_error(dev, dma_dest)) {
+ dev_err(dev, "mapping dest buffer failed\n");
+ goto unmap_src;
+ }
+ flags = DMA_PREP_INTERRUPT;
+ tx = device->common.device_prep_dma_memcpy(dma_chan, dma_dest, dma_src,
+ IOAT_TEST_SIZE, flags);
+ if (!tx) {
+ dev_err(dev, "Self-test prep failed, disabling\n");
+ err = -ENODEV;
+ goto unmap_dma;
+ }
+
+ 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(dev, "Self-test setup failed, disabling\n");
+ err = -ENODEV;
+ goto unmap_dma;
+ }
+ dma->device_issue_pending(dma_chan);
+
+ tmo = wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000));
+
+ if (tmo == 0 ||
+ dma->device_tx_status(dma_chan, cookie, NULL)
+ != DMA_COMPLETE) {
+ dev_err(dev, "Self-test copy timed out, disabling\n");
+ err = -ENODEV;
+ goto unmap_dma;
+ }
+ if (memcmp(src, dest, IOAT_TEST_SIZE)) {
+ dev_err(dev, "Self-test copy failed compare, disabling\n");
+ err = -ENODEV;
+ goto free_resources;
+ }
+
+unmap_dma:
+ dma_unmap_single(dev, dma_dest, IOAT_TEST_SIZE, DMA_FROM_DEVICE);
+unmap_src:
+ dma_unmap_single(dev, dma_src, IOAT_TEST_SIZE, DMA_TO_DEVICE);
+free_resources:
+ dma->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), msi, intx");
+
+/**
+ * ioat_dma_setup_interrupts - setup interrupt handler
+ * @device: ioat device
+ */
+int ioat_dma_setup_interrupts(struct ioatdma_device *device)
+{
+ struct ioat_chan_common *chan;
+ struct pci_dev *pdev = device->pdev;
+ struct device *dev = &pdev->dev;
+ struct msix_entry *msix;
+ int i, j, msixcnt;
+ int err = -EINVAL;
+ u8 intrctrl = 0;
+
+ if (!strcmp(ioat_interrupt_style, "msix"))
+ goto msix;
+ if (!strcmp(ioat_interrupt_style, "msi"))
+ goto msi;
+ if (!strcmp(ioat_interrupt_style, "intx"))
+ goto intx;
+ dev_err(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_exact(pdev, device->msix_entries, msixcnt);
+ if (err)
+ goto msi;
+
+ for (i = 0; i < msixcnt; i++) {
+ msix = &device->msix_entries[i];
+ chan = ioat_chan_by_index(device, i);
+ err = devm_request_irq(dev, msix->vector,
+ ioat_dma_do_interrupt_msix, 0,
+ "ioat-msix", chan);
+ if (err) {
+ for (j = 0; j < i; j++) {
+ msix = &device->msix_entries[j];
+ chan = ioat_chan_by_index(device, j);
+ devm_free_irq(dev, msix->vector, chan);
+ }
+ goto msi;
+ }
+ }
+ intrctrl |= IOAT_INTRCTRL_MSIX_VECTOR_CONTROL;
+ device->irq_mode = IOAT_MSIX;
+ goto done;
+
+msi:
+ err = pci_enable_msi(pdev);
+ if (err)
+ goto intx;
+
+ err = devm_request_irq(dev, pdev->irq, ioat_dma_do_interrupt, 0,
+ "ioat-msi", device);
+ if (err) {
+ pci_disable_msi(pdev);
+ goto intx;
+ }
+ device->irq_mode = IOAT_MSI;
+ goto done;
+
+intx:
+ err = devm_request_irq(dev, pdev->irq, ioat_dma_do_interrupt,
+ IRQF_SHARED, "ioat-intx", device);
+ if (err)
+ goto err_no_irq;
+
+ device->irq_mode = IOAT_INTX;
+done:
+ if (device->intr_quirk)
+ device->intr_quirk(device);
+ 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);
+ device->irq_mode = IOAT_NOIRQ;
+ dev_err(dev, "no usable interrupts\n");
+ return err;
+}
+EXPORT_SYMBOL(ioat_dma_setup_interrupts);
+
+static void ioat_disable_interrupts(struct ioatdma_device *device)
+{
+ /* Disable all interrupt generation */
+ writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
+}
+
+int ioat_probe(struct ioatdma_device *device)
+{
+ int err = -ENODEV;
+ struct dma_device *dma = &device->common;
+ struct pci_dev *pdev = device->pdev;
+ struct device *dev = &pdev->dev;
+
+ /* 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->enumerate_channels(device);
+
+ dma_cap_set(DMA_MEMCPY, dma->cap_mask);
+ dma->dev = &pdev->dev;
+
+ if (!dma->chancnt) {
+ dev_err(dev, "channel enumeration error\n");
+ goto err_setup_interrupts;
+ }
+
+ err = ioat_dma_setup_interrupts(device);
+ if (err)
+ goto err_setup_interrupts;
+
+ err = device->self_test(device);
+ if (err)
+ goto err_self_test;
+
+ return 0;
+
+err_self_test:
+ ioat_disable_interrupts(device);
+err_setup_interrupts:
+ pci_pool_destroy(device->completion_pool);
+err_completion_pool:
+ pci_pool_destroy(device->dma_pool);
+err_dma_pool:
+ return err;
+}
+
+int ioat_register(struct ioatdma_device *device)
+{
+ int err = dma_async_device_register(&device->common);
+
+ if (err) {
+ ioat_disable_interrupts(device);
+ pci_pool_destroy(device->completion_pool);
+ pci_pool_destroy(device->dma_pool);
+ }
+
+ return err;
+}
+
+/* ioat1_intr_quirk - fix up dma ctrl register to enable / disable msi */
+static void ioat1_intr_quirk(struct ioatdma_device *device)
+{
+ struct pci_dev *pdev = device->pdev;
+ u32 dmactrl;
+
+ pci_read_config_dword(pdev, IOAT_PCI_DMACTRL_OFFSET, &dmactrl);
+ if (pdev->msi_enabled)
+ dmactrl |= IOAT_PCI_DMACTRL_MSI_EN;
+ else
+ dmactrl &= ~IOAT_PCI_DMACTRL_MSI_EN;
+ pci_write_config_dword(pdev, IOAT_PCI_DMACTRL_OFFSET, dmactrl);
+}
+
+static ssize_t ring_size_show(struct dma_chan *c, char *page)
+{
+ struct ioat_dma_chan *ioat = to_ioat_chan(c);
+
+ return sprintf(page, "%d\n", ioat->desccount);
+}
+static struct ioat_sysfs_entry ring_size_attr = __ATTR_RO(ring_size);
+
+static ssize_t ring_active_show(struct dma_chan *c, char *page)
+{
+ struct ioat_dma_chan *ioat = to_ioat_chan(c);
+
+ return sprintf(page, "%d\n", ioat->active);
+}
+static struct ioat_sysfs_entry ring_active_attr = __ATTR_RO(ring_active);
+
+static ssize_t cap_show(struct dma_chan *c, char *page)
+{
+ struct dma_device *dma = c->device;
+
+ return sprintf(page, "copy%s%s%s%s%s\n",
+ dma_has_cap(DMA_PQ, dma->cap_mask) ? " pq" : "",
+ dma_has_cap(DMA_PQ_VAL, dma->cap_mask) ? " pq_val" : "",
+ dma_has_cap(DMA_XOR, dma->cap_mask) ? " xor" : "",
+ dma_has_cap(DMA_XOR_VAL, dma->cap_mask) ? " xor_val" : "",
+ dma_has_cap(DMA_INTERRUPT, dma->cap_mask) ? " intr" : "");
+
+}
+struct ioat_sysfs_entry ioat_cap_attr = __ATTR_RO(cap);
+
+static ssize_t version_show(struct dma_chan *c, char *page)
+{
+ struct dma_device *dma = c->device;
+ struct ioatdma_device *device = to_ioatdma_device(dma);
+
+ return sprintf(page, "%d.%d\n",
+ device->version >> 4, device->version & 0xf);
+}
+struct ioat_sysfs_entry ioat_version_attr = __ATTR_RO(version);
+
+static struct attribute *ioat1_attrs[] = {
+ &ring_size_attr.attr,
+ &ring_active_attr.attr,
+ &ioat_cap_attr.attr,
+ &ioat_version_attr.attr,
+ NULL,
+};
+
+static ssize_t
+ioat_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
+{
+ struct ioat_sysfs_entry *entry;
+ struct ioat_chan_common *chan;
+
+ entry = container_of(attr, struct ioat_sysfs_entry, attr);
+ chan = container_of(kobj, struct ioat_chan_common, kobj);
+
+ if (!entry->show)
+ return -EIO;
+ return entry->show(&chan->common, page);
+}
+
+const struct sysfs_ops ioat_sysfs_ops = {
+ .show = ioat_attr_show,
+};
+
+static struct kobj_type ioat1_ktype = {
+ .sysfs_ops = &ioat_sysfs_ops,
+ .default_attrs = ioat1_attrs,
+};
+
+void ioat_kobject_add(struct ioatdma_device *device, struct kobj_type *type)
+{
+ struct dma_device *dma = &device->common;
+ struct dma_chan *c;
+
+ list_for_each_entry(c, &dma->channels, device_node) {
+ struct ioat_chan_common *chan = to_chan_common(c);
+ struct kobject *parent = &c->dev->device.kobj;
+ int err;
+
+ err = kobject_init_and_add(&chan->kobj, type, parent, "quickdata");
+ if (err) {
+ dev_warn(to_dev(chan),
+ "sysfs init error (%d), continuing...\n", err);
+ kobject_put(&chan->kobj);
+ set_bit(IOAT_KOBJ_INIT_FAIL, &chan->state);
+ }
+ }
+}
+
+void ioat_kobject_del(struct ioatdma_device *device)
+{
+ struct dma_device *dma = &device->common;
+ struct dma_chan *c;
+
+ list_for_each_entry(c, &dma->channels, device_node) {
+ struct ioat_chan_common *chan = to_chan_common(c);
+
+ if (!test_bit(IOAT_KOBJ_INIT_FAIL, &chan->state)) {
+ kobject_del(&chan->kobj);
+ kobject_put(&chan->kobj);
+ }
+ }
+}
+
+int ioat1_dma_probe(struct ioatdma_device *device, int dca)
+{
+ struct pci_dev *pdev = device->pdev;
+ struct dma_device *dma;
+ int err;
+
+ device->intr_quirk = ioat1_intr_quirk;
+ device->enumerate_channels = ioat1_enumerate_channels;
+ device->self_test = ioat_dma_self_test;
+ device->timer_fn = ioat1_timer_event;
+ device->cleanup_fn = ioat1_cleanup_event;
+ dma = &device->common;
+ dma->device_prep_dma_memcpy = ioat1_dma_prep_memcpy;
+ dma->device_issue_pending = ioat1_dma_memcpy_issue_pending;
+ dma->device_alloc_chan_resources = ioat1_dma_alloc_chan_resources;
+ dma->device_free_chan_resources = ioat1_dma_free_chan_resources;
+ dma->device_tx_status = ioat_dma_tx_status;
+
+ err = ioat_probe(device);
+ if (err)
+ return err;
+ err = ioat_register(device);
+ if (err)
+ return err;
+ ioat_kobject_add(device, &ioat1_ktype);
+
+ if (dca)
+ device->dca = ioat_dca_init(pdev, device->reg_base);
+
+ return err;
+}
+
+void ioat_dma_remove(struct ioatdma_device *device)
+{
+ struct dma_device *dma = &device->common;
+
+ ioat_disable_interrupts(device);
+
+ ioat_kobject_del(device);
+
+ dma_async_device_unregister(dma);
+
+ pci_pool_destroy(device->dma_pool);
+ pci_pool_destroy(device->completion_pool);
+
+ INIT_LIST_HEAD(&dma->channels);
+}
Code Review / kvmfornfv.git / blobdiff