/* * 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 #include #include #include #include #include #include #include #include #include "dma.h" #include "registers.h" #include "hw.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_bit(bit, &attnstatus, BITS_PER_LONG) { chan = ioat_chan_by_index(instance, bit); 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; tasklet_schedule(&chan->cleanup_task); return IRQ_HANDLED; } static void ioat1_cleanup_tasklet(unsigned long data); /* common channel initialization */ void ioat_init_channel(struct ioatdma_device *device, struct ioat_chan_common *chan, int idx, work_func_t work_fn, void (*tasklet)(unsigned long), unsigned long tasklet_data) { struct dma_device *dma = &device->common; chan->device = device; chan->reg_base = device->reg_base + (0x80 * (idx + 1)); INIT_DELAYED_WORK(&chan->work, work_fn); spin_lock_init(&chan->cleanup_lock); chan->common.device = dma; list_add_tail(&chan->common.device_node, &dma->channels); device->idx[idx] = chan; tasklet_init(&chan->cleanup_task, tasklet, tasklet_data); tasklet_disable(&chan->cleanup_task); } static void ioat1_reset_part2(struct work_struct *work); /** * 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); xfercap_scale = readb(device->reg_base + IOAT_XFERCAP_OFFSET); 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, ioat1_reset_part2, ioat1_cleanup_tasklet, (unsigned long) ioat); 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_part2 - reinit the channel after a reset */ static void ioat1_reset_part2(struct work_struct *work) { struct ioat_chan_common *chan; struct ioat_dma_chan *ioat; struct ioat_desc_sw *desc; int dmacount; bool start_null = false; chan = container_of(work, struct ioat_chan_common, work.work); ioat = container_of(chan, struct ioat_dma_chan, base); spin_lock_bh(&chan->cleanup_lock); spin_lock_bh(&ioat->desc_lock); chan->completion_virt->low = 0; chan->completion_virt->high = 0; ioat->pending = 0; /* count the descriptors waiting */ dmacount = 0; if (ioat->used_desc.prev) { desc = to_ioat_desc(ioat->used_desc.prev); do { dmacount++; desc = to_ioat_desc(desc->node.next); } while (&desc->node != ioat->used_desc.next); } if (dmacount) { /* * write the new starting descriptor address * this puts channel engine into ARMED state */ desc = to_ioat_desc(ioat->used_desc.prev); writel(((u64) desc->txd.phys) & 0x00000000FFFFFFFF, chan->reg_base + IOAT1_CHAINADDR_OFFSET_LOW); writel(((u64) desc->txd.phys) >> 32, chan->reg_base + IOAT1_CHAINADDR_OFFSET_HIGH); writeb(IOAT_CHANCMD_START, chan->reg_base + IOAT_CHANCMD_OFFSET(chan->device->version)); } else start_null = true; spin_unlock_bh(&ioat->desc_lock); spin_unlock_bh(&chan->cleanup_lock); dev_err(to_dev(chan), "chan%d reset - %d descs waiting, %d total desc\n", chan_num(chan), dmacount, ioat->desccount); if (start_null) ioat1_dma_start_null_desc(ioat); } /** * 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; if (!ioat->used_desc.prev) return; dev_dbg(to_dev(chan), "%s\n", __func__); chanerr = readl(reg_base + IOAT_CHANERR_OFFSET); chansts = (chan->completion_virt->low & IOAT_CHANSTS_DMA_TRANSFER_STATUS); if (chanerr) { dev_err(to_dev(chan), "chan%d, CHANSTS = 0x%08x CHANERR = 0x%04x, clearing\n", chan_num(chan), chansts, chanerr); writel(chanerr, 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->desc_lock); ioat->pending = INT_MIN; writeb(IOAT_CHANCMD_RESET, reg_base + IOAT_CHANCMD_OFFSET(chan->device->version)); spin_unlock_bh(&ioat->desc_lock); /* schedule the 2nd half instead of sleeping a long time */ schedule_delayed_work(&chan->work, RESET_DELAY); } /** * ioat1_chan_watchdog - watch for stuck channels */ static void ioat1_chan_watchdog(struct work_struct *work) { struct ioatdma_device *device = container_of(work, struct ioatdma_device, work.work); struct ioat_dma_chan *ioat; struct ioat_chan_common *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++) { chan = ioat_chan_by_index(device, i); ioat = container_of(chan, struct ioat_dma_chan, base); if (/* have we started processing anything yet */ chan->last_completion /* have we completed any since last watchdog cycle? */ && (chan->last_completion == chan->watchdog_completion) /* has TCP stuck on one cookie since last watchdog? */ && (chan->watchdog_tcp_cookie == chan->watchdog_last_tcp_cookie) && (chan->watchdog_tcp_cookie != chan->completed_cookie) /* is there something in the chain to be processed? */ /* CB1 chain always has at least the last one processed */ && (ioat->used_desc.prev != ioat->used_desc.next) && ioat->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(chan->reg_base + IOAT_CHANSTS_OFFSET_LOW(chan->device->version)); completion_hw.high = readl(chan->reg_base + IOAT_CHANSTS_OFFSET_HIGH(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 != chan->watchdog_completion) && (compl_desc_addr_hw != chan->last_compl_desc_addr_hw)) { chan->last_compl_desc_addr_hw = compl_desc_addr_hw; chan->completion_virt->low = completion_hw.low; chan->completion_virt->high = completion_hw.high; } else { ioat1_reset_channel(ioat); chan->watchdog_completion = 0; chan->last_compl_desc_addr_hw = 0; } } else { chan->last_compl_desc_addr_hw = 0; chan->watchdog_completion = chan->last_completion; } chan->watchdog_last_tcp_cookie = chan->watchdog_tcp_cookie; } schedule_delayed_work(&device->work, WATCHDOG_DELAY); } 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_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 = c->cookie; cookie++; if (cookie < 0) cookie = 1; c->cookie = cookie; tx->cookie = cookie; 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(tx->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(&tx->tx_list, &ioat->used_desc); dump_desc_dbg(ioat, chain_tail); dump_desc_dbg(ioat, first); ioat->pending += desc->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)); 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; u16 chanctrl; 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 */ chanctrl = IOAT_CHANCTRL_ERR_INT_EN | IOAT_CHANCTRL_ANY_ERR_ABORT_EN | IOAT_CHANCTRL_ERR_COMPLETION_EN; writew(chanctrl, chan->reg_base + IOAT_CHANCTRL_OFFSET); chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET); if (chanerr) { dev_err(to_dev(chan), "CHANERR = %x, clearing\n", chanerr); writel(chanerr, chan->reg_base + IOAT_CHANERR_OFFSET); } /* Allocate 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_virt = pci_pool_alloc(chan->device->completion_pool, GFP_KERNEL, &chan->completion_addr); memset(chan->completion_virt, 0, sizeof(*chan->completion_virt)); writel(((u64) chan->completion_addr) & 0x00000000FFFFFFFF, chan->reg_base + IOAT_CHANCMP_OFFSET_LOW); writel(((u64) chan->completion_addr) >> 32, chan->reg_base + IOAT_CHANCMP_OFFSET_HIGH); tasklet_enable(&chan->cleanup_task); 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; } /** * 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; tasklet_disable(&chan->cleanup_task); ioat1_cleanup(ioat); /* Delay 100ms after reset to allow internal DMA logic to quiesce * before removing DMA descriptor resources. */ writeb(IOAT_CHANCMD_RESET, chan->reg_base + IOAT_CHANCMD_OFFSET(chan->device->version)); mdelay(100); spin_lock_bh(&ioat->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_virt, chan->completion_addr); /* 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 = chan->completion_addr = 0; chan->watchdog_completion = 0; chan->last_compl_desc_addr_hw = 0; chan->watchdog_tcp_cookie = chan->watchdog_last_tcp_cookie = 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->tx_cnt = tx_cnt; desc->len = total_len; list_splice(&chain, &desc->txd.tx_list); hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT); hw->ctl_f.compl_write = 1; dump_desc_dbg(ioat, desc); return &desc->txd; } static void ioat1_cleanup_tasklet(unsigned long data) { struct ioat_dma_chan *chan = (void *)data; ioat1_cleanup(chan); writew(IOAT_CHANCTRL_INT_DISABLE, chan->base.reg_base + IOAT_CHANCTRL_OFFSET); } static void ioat_unmap(struct pci_dev *pdev, dma_addr_t addr, size_t len, int direction, enum dma_ctrl_flags flags, bool dst) { if ((dst && (flags & DMA_COMPL_DEST_UNMAP_SINGLE)) || (!dst && (flags & DMA_COMPL_SRC_UNMAP_SINGLE))) pci_unmap_single(pdev, addr, len, direction); else pci_unmap_page(pdev, addr, len, direction); } void ioat_dma_unmap(struct ioat_chan_common *chan, enum dma_ctrl_flags flags, size_t len, struct ioat_dma_descriptor *hw) { struct pci_dev *pdev = chan->device->pdev; size_t offset = len - hw->size; if (!(flags & DMA_COMPL_SKIP_DEST_UNMAP)) ioat_unmap(pdev, hw->dst_addr - offset, len, PCI_DMA_FROMDEVICE, flags, 1); if (!(flags & DMA_COMPL_SKIP_SRC_UNMAP)) ioat_unmap(pdev, hw->src_addr - offset, len, PCI_DMA_TODEVICE, flags, 0); } unsigned long ioat_get_current_completion(struct ioat_chan_common *chan) { unsigned long phys_complete; /* 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 dev_dbg(to_dev(chan), "%s: phys_complete: %#llx\n", __func__, (unsigned long long) phys_complete); if ((chan->completion_virt->full & IOAT_CHANSTS_DMA_TRANSFER_STATUS) == IOAT_CHANSTS_DMA_TRANSFER_STATUS_HALTED) { dev_err(to_dev(chan), "Channel halted, chanerr = %x\n", readl(chan->reg_base + IOAT_CHANERR_OFFSET)); /* TODO do something to salvage the situation */ } return phys_complete; } /** * ioat1_cleanup - cleanup up finished descriptors * @chan: ioat channel to be cleaned up */ static void ioat1_cleanup(struct ioat_dma_chan *ioat) { struct ioat_chan_common *chan = &ioat->base; unsigned long phys_complete; struct ioat_desc_sw *desc, *_desc; dma_cookie_t cookie = 0; struct dma_async_tx_descriptor *tx; prefetch(chan->completion_virt); if (!spin_trylock_bh(&chan->cleanup_lock)) return; phys_complete = ioat_get_current_completion(chan); if (phys_complete == chan->last_completion) { spin_unlock_bh(&chan->cleanup_lock); /* * perhaps we're stuck so hard that the watchdog can't go off? * try to catch it after 2 seconds */ if (time_after(jiffies, chan->last_completion_time + HZ*WATCHDOG_DELAY)) { ioat1_chan_watchdog(&(chan->device->work.work)); chan->last_completion_time = jiffies; } return; } chan->last_completion_time = jiffies; cookie = 0; if (!spin_trylock_bh(&ioat->desc_lock)) { spin_unlock_bh(&chan->cleanup_lock); return; } dev_dbg(to_dev(chan), "%s: phys_complete: %lx\n", __func__, phys_complete); list_for_each_entry_safe(desc, _desc, &ioat->used_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) { cookie = tx->cookie; ioat_dma_unmap(chan, tx->flags, desc->len, desc->hw); 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 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 */ tx->cookie = 0; /* TODO check status bits? */ break; } } spin_unlock_bh(&ioat->desc_lock); chan->last_completion = phys_complete; if (cookie != 0) chan->completed_cookie = cookie; spin_unlock_bh(&chan->cleanup_lock); } static enum dma_status ioat1_dma_is_complete(struct dma_chan *c, dma_cookie_t cookie, dma_cookie_t *done, dma_cookie_t *used) { struct ioat_dma_chan *ioat = to_ioat_chan(c); if (ioat_is_complete(c, cookie, done, used) == DMA_SUCCESS) return DMA_SUCCESS; ioat1_cleanup(ioat); return ioat_is_complete(c, cookie, done, used); } 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); writel(((u64) desc->txd.phys) & 0x00000000FFFFFFFF, chan->reg_base + IOAT1_CHAINADDR_OFFSET_LOW); writel(((u64) desc->txd.phys) >> 32, chan->reg_base + IOAT1_CHAINADDR_OFFSET_HIGH); writeb(IOAT_CHANCMD_START, chan->reg_base + IOAT_CHANCMD_OFFSET(chan->device->version)); 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 */ static 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); dma_dest = dma_map_single(dev, dest, IOAT_TEST_SIZE, DMA_FROM_DEVICE); flags = DMA_COMPL_SRC_UNMAP_SINGLE | DMA_COMPL_DEST_UNMAP_SINGLE | 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 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(dev, "Self-test setup failed, disabling\n"); err = -ENODEV; goto free_resources; } dma->device_issue_pending(dma_chan); tmo = wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)); if (tmo == 0 || dma->device_is_tx_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) { dev_err(dev, "Self-test copy timed out, disabling\n"); err = -ENODEV; goto free_resources; } if (memcmp(src, dest, IOAT_TEST_SIZE)) { dev_err(dev, "Self-test copy failed compare, disabling\n"); err = -ENODEV; goto free_resources; } 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), " "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_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, "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(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(pdev, device->msix_entries, msixcnt); if (err < 0) goto msi; if (err > 0) goto msix_single_vector; 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 msix_single_vector; } } intrctrl |= IOAT_INTRCTRL_MSIX_VECTOR_CONTROL; goto done; msix_single_vector: msix = &device->msix_entries[0]; msix->entry = 0; err = pci_enable_msix(pdev, device->msix_entries, 1); if (err) goto msi; err = devm_request_irq(dev, msix->vector, ioat_dma_do_interrupt, 0, "ioat-msix", device); if (err) { pci_disable_msix(pdev); goto msi; } 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; } 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; 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); dev_err(dev, "no usable interrupts\n"); return err; } 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; dev_err(dev, "Intel(R) I/OAT DMA Engine found," " %d channels, device version 0x%02x, driver version %s\n", dma->chancnt, device->version, IOAT_DMA_VERSION); if (!dma->chancnt) { dev_err(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; 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); } 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; 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_is_tx_complete = ioat1_dma_is_complete; err = ioat_probe(device); if (err) return err; ioat_set_tcp_copy_break(4096); err = ioat_register(device); if (err) return err; if (dca) device->dca = ioat_dca_init(pdev, device->reg_base); INIT_DELAYED_WORK(&device->work, ioat1_chan_watchdog); schedule_delayed_work(&device->work, WATCHDOG_DELAY); return err; } void ioat_dma_remove(struct ioatdma_device *device) { struct dma_device *dma = &device->common; if (device->version != IOAT_VER_3_0) cancel_delayed_work(&device->work); ioat_disable_interrupts(device); dma_async_device_unregister(dma); pci_pool_destroy(device->dma_pool); pci_pool_destroy(device->completion_pool); INIT_LIST_HEAD(&dma->channels); }