diff options
Diffstat (limited to 'drivers/dma/ioat/dma_v2.c')
| -rw-r--r-- | drivers/dma/ioat/dma_v2.c | 916 |
1 files changed, 916 insertions, 0 deletions
diff --git a/drivers/dma/ioat/dma_v2.c b/drivers/dma/ioat/dma_v2.c new file mode 100644 index 000000000..69c7dfcad --- /dev/null +++ b/drivers/dma/ioat/dma_v2.c @@ -0,0 +1,916 @@ +/* + * 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 (versions >= 2), which + * does asynchronous data movement and checksumming 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 "dma_v2.h" +#include "registers.h" +#include "hw.h" + +#include "../dmaengine.h" + +int ioat_ring_alloc_order = 8; +module_param(ioat_ring_alloc_order, int, 0644); +MODULE_PARM_DESC(ioat_ring_alloc_order, + "ioat2+: allocate 2^n descriptors per channel" + " (default: 8 max: 16)"); +static int ioat_ring_max_alloc_order = IOAT_MAX_ORDER; +module_param(ioat_ring_max_alloc_order, int, 0644); +MODULE_PARM_DESC(ioat_ring_max_alloc_order, + "ioat2+: upper limit for ring size (default: 16)"); + +void __ioat2_issue_pending(struct ioat2_dma_chan *ioat) +{ + struct ioat_chan_common *chan = &ioat->base; + + ioat->dmacount += ioat2_ring_pending(ioat); + ioat->issued = ioat->head; + writew(ioat->dmacount, chan->reg_base + IOAT_CHAN_DMACOUNT_OFFSET); + dev_dbg(to_dev(chan), + "%s: head: %#x tail: %#x issued: %#x count: %#x\n", + __func__, ioat->head, ioat->tail, ioat->issued, ioat->dmacount); +} + +void ioat2_issue_pending(struct dma_chan *c) +{ + struct ioat2_dma_chan *ioat = to_ioat2_chan(c); + + if (ioat2_ring_pending(ioat)) { + spin_lock_bh(&ioat->prep_lock); + __ioat2_issue_pending(ioat); + spin_unlock_bh(&ioat->prep_lock); + } +} + +/** + * ioat2_update_pending - log pending descriptors + * @ioat: ioat2+ channel + * + * Check if the number of unsubmitted descriptors has exceeded the + * watermark. Called with prep_lock held + */ +static void ioat2_update_pending(struct ioat2_dma_chan *ioat) +{ + if (ioat2_ring_pending(ioat) > ioat_pending_level) + __ioat2_issue_pending(ioat); +} + +static void __ioat2_start_null_desc(struct ioat2_dma_chan *ioat) +{ + struct ioat_ring_ent *desc; + struct ioat_dma_descriptor *hw; + + if (ioat2_ring_space(ioat) < 1) { + dev_err(to_dev(&ioat->base), + "Unable to start null desc - ring full\n"); + return; + } + + dev_dbg(to_dev(&ioat->base), "%s: head: %#x tail: %#x issued: %#x\n", + __func__, ioat->head, ioat->tail, ioat->issued); + desc = ioat2_get_ring_ent(ioat, ioat->head); + + 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); + ioat2_set_chainaddr(ioat, desc->txd.phys); + dump_desc_dbg(ioat, desc); + wmb(); + ioat->head += 1; + __ioat2_issue_pending(ioat); +} + +static void ioat2_start_null_desc(struct ioat2_dma_chan *ioat) +{ + spin_lock_bh(&ioat->prep_lock); + __ioat2_start_null_desc(ioat); + spin_unlock_bh(&ioat->prep_lock); +} + +static void __cleanup(struct ioat2_dma_chan *ioat, dma_addr_t phys_complete) +{ + struct ioat_chan_common *chan = &ioat->base; + struct dma_async_tx_descriptor *tx; + struct ioat_ring_ent *desc; + bool seen_current = false; + u16 active; + int idx = ioat->tail, i; + + dev_dbg(to_dev(chan), "%s: head: %#x tail: %#x issued: %#x\n", + __func__, ioat->head, ioat->tail, ioat->issued); + + active = ioat2_ring_active(ioat); + for (i = 0; i < active && !seen_current; i++) { + smp_read_barrier_depends(); + prefetch(ioat2_get_ring_ent(ioat, idx + i + 1)); + desc = ioat2_get_ring_ent(ioat, idx + i); + tx = &desc->txd; + dump_desc_dbg(ioat, desc); + if (tx->cookie) { + dma_descriptor_unmap(tx); + dma_cookie_complete(tx); + if (tx->callback) { + tx->callback(tx->callback_param); + tx->callback = NULL; + } + } + + if (tx->phys == phys_complete) + seen_current = true; + } + smp_mb(); /* finish all descriptor reads before incrementing tail */ + ioat->tail = idx + i; + BUG_ON(active && !seen_current); /* no active descs have written a completion? */ + + chan->last_completion = phys_complete; + if (active - i == 0) { + dev_dbg(to_dev(chan), "%s: cancel completion timeout\n", + __func__); + clear_bit(IOAT_COMPLETION_PENDING, &chan->state); + mod_timer(&chan->timer, jiffies + IDLE_TIMEOUT); + } +} + +/** + * ioat2_cleanup - clean finished descriptors (advance tail pointer) + * @chan: ioat channel to be cleaned up + */ +static void ioat2_cleanup(struct ioat2_dma_chan *ioat) +{ + struct ioat_chan_common *chan = &ioat->base; + dma_addr_t phys_complete; + + spin_lock_bh(&chan->cleanup_lock); + if (ioat_cleanup_preamble(chan, &phys_complete)) + __cleanup(ioat, phys_complete); + spin_unlock_bh(&chan->cleanup_lock); +} + +void ioat2_cleanup_event(unsigned long data) +{ + struct ioat2_dma_chan *ioat = to_ioat2_chan((void *) data); + struct ioat_chan_common *chan = &ioat->base; + + ioat2_cleanup(ioat); + if (!test_bit(IOAT_RUN, &chan->state)) + return; + writew(IOAT_CHANCTRL_RUN, ioat->base.reg_base + IOAT_CHANCTRL_OFFSET); +} + +void __ioat2_restart_chan(struct ioat2_dma_chan *ioat) +{ + struct ioat_chan_common *chan = &ioat->base; + + /* set the tail to be re-issued */ + ioat->issued = ioat->tail; + ioat->dmacount = 0; + set_bit(IOAT_COMPLETION_PENDING, &chan->state); + mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT); + + dev_dbg(to_dev(chan), + "%s: head: %#x tail: %#x issued: %#x count: %#x\n", + __func__, ioat->head, ioat->tail, ioat->issued, ioat->dmacount); + + if (ioat2_ring_pending(ioat)) { + struct ioat_ring_ent *desc; + + desc = ioat2_get_ring_ent(ioat, ioat->tail); + ioat2_set_chainaddr(ioat, desc->txd.phys); + __ioat2_issue_pending(ioat); + } else + __ioat2_start_null_desc(ioat); +} + +int ioat2_quiesce(struct ioat_chan_common *chan, unsigned long tmo) +{ + unsigned long end = jiffies + tmo; + int err = 0; + u32 status; + + status = ioat_chansts(chan); + if (is_ioat_active(status) || is_ioat_idle(status)) + ioat_suspend(chan); + while (is_ioat_active(status) || is_ioat_idle(status)) { + if (tmo && time_after(jiffies, end)) { + err = -ETIMEDOUT; + break; + } + status = ioat_chansts(chan); + cpu_relax(); + } + + return err; +} + +int ioat2_reset_sync(struct ioat_chan_common *chan, unsigned long tmo) +{ + unsigned long end = jiffies + tmo; + int err = 0; + + ioat_reset(chan); + while (ioat_reset_pending(chan)) { + if (end && time_after(jiffies, end)) { + err = -ETIMEDOUT; + break; + } + cpu_relax(); + } + + return err; +} + +static void ioat2_restart_channel(struct ioat2_dma_chan *ioat) +{ + struct ioat_chan_common *chan = &ioat->base; + dma_addr_t phys_complete; + + ioat2_quiesce(chan, 0); + if (ioat_cleanup_preamble(chan, &phys_complete)) + __cleanup(ioat, phys_complete); + + __ioat2_restart_chan(ioat); +} + +static void check_active(struct ioat2_dma_chan *ioat) +{ + struct ioat_chan_common *chan = &ioat->base; + + if (ioat2_ring_active(ioat)) { + mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT); + return; + } + + if (test_and_clear_bit(IOAT_CHAN_ACTIVE, &chan->state)) + mod_timer(&chan->timer, jiffies + IDLE_TIMEOUT); + else if (ioat->alloc_order > ioat_get_alloc_order()) { + /* if the ring is idle, empty, and oversized try to step + * down the size + */ + reshape_ring(ioat, ioat->alloc_order - 1); + + /* keep shrinking until we get back to our minimum + * default size + */ + if (ioat->alloc_order > ioat_get_alloc_order()) + mod_timer(&chan->timer, jiffies + IDLE_TIMEOUT); + } + +} + +void ioat2_timer_event(unsigned long data) +{ + struct ioat2_dma_chan *ioat = to_ioat2_chan((void *) data); + struct ioat_chan_common *chan = &ioat->base; + dma_addr_t phys_complete; + u64 status; + + status = ioat_chansts(chan); + + /* when halted due to errors check for channel + * programming errors before advancing the completion state + */ + if (is_ioat_halted(status)) { + u32 chanerr; + + chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET); + dev_err(to_dev(chan), "%s: Channel halted (%x)\n", + __func__, chanerr); + if (test_bit(IOAT_RUN, &chan->state)) + BUG_ON(is_ioat_bug(chanerr)); + else /* we never got off the ground */ + return; + } + + /* if we haven't made progress and we have already + * acknowledged a pending completion once, then be more + * forceful with a restart + */ + spin_lock_bh(&chan->cleanup_lock); + if (ioat_cleanup_preamble(chan, &phys_complete)) + __cleanup(ioat, phys_complete); + else if (test_bit(IOAT_COMPLETION_ACK, &chan->state)) { + spin_lock_bh(&ioat->prep_lock); + ioat2_restart_channel(ioat); + spin_unlock_bh(&ioat->prep_lock); + spin_unlock_bh(&chan->cleanup_lock); + return; + } else { + set_bit(IOAT_COMPLETION_ACK, &chan->state); + mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT); + } + + + if (ioat2_ring_active(ioat)) + mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT); + else { + spin_lock_bh(&ioat->prep_lock); + check_active(ioat); + spin_unlock_bh(&ioat->prep_lock); + } + spin_unlock_bh(&chan->cleanup_lock); +} + +static int ioat2_reset_hw(struct ioat_chan_common *chan) +{ + /* throw away whatever the channel was doing and get it initialized */ + u32 chanerr; + + ioat2_quiesce(chan, msecs_to_jiffies(100)); + + chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET); + writel(chanerr, chan->reg_base + IOAT_CHANERR_OFFSET); + + return ioat2_reset_sync(chan, msecs_to_jiffies(200)); +} + +/** + * ioat2_enumerate_channels - find and initialize the device's channels + * @device: the device to be enumerated + */ +int ioat2_enumerate_channels(struct ioatdma_device *device) +{ + struct ioat2_dma_chan *ioat; + struct device *dev = &device->pdev->dev; + struct dma_device *dma = &device->common; + u8 xfercap_log; + int i; + + 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_log = readb(device->reg_base + IOAT_XFERCAP_OFFSET); + xfercap_log &= 0x1f; /* bits [4:0] valid */ + if (xfercap_log == 0) + return 0; + dev_dbg(dev, "%s: xfercap = %d\n", __func__, 1 << xfercap_log); + + /* FIXME which i/oat version is i7300? */ +#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_log = xfercap_log; + spin_lock_init(&ioat->prep_lock); + if (device->reset_hw(&ioat->base)) { + i = 0; + break; + } + } + dma->chancnt = i; + return i; +} + +static dma_cookie_t ioat2_tx_submit_unlock(struct dma_async_tx_descriptor *tx) +{ + struct dma_chan *c = tx->chan; + struct ioat2_dma_chan *ioat = to_ioat2_chan(c); + struct ioat_chan_common *chan = &ioat->base; + dma_cookie_t cookie; + + cookie = dma_cookie_assign(tx); + dev_dbg(to_dev(&ioat->base), "%s: cookie: %d\n", __func__, cookie); + + if (!test_and_set_bit(IOAT_CHAN_ACTIVE, &chan->state)) + mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT); + + /* make descriptor updates visible before advancing ioat->head, + * this is purposefully not smp_wmb() since we are also + * publishing the descriptor updates to a dma device + */ + wmb(); + + ioat->head += ioat->produce; + + ioat2_update_pending(ioat); + spin_unlock_bh(&ioat->prep_lock); + + return cookie; +} + +static struct ioat_ring_ent *ioat2_alloc_ring_ent(struct dma_chan *chan, gfp_t flags) +{ + struct ioat_dma_descriptor *hw; + struct ioat_ring_ent *desc; + struct ioatdma_device *dma; + dma_addr_t phys; + + dma = to_ioatdma_device(chan->device); + hw = pci_pool_alloc(dma->dma_pool, flags, &phys); + if (!hw) + return NULL; + memset(hw, 0, sizeof(*hw)); + + desc = kmem_cache_zalloc(ioat2_cache, flags); + if (!desc) { + pci_pool_free(dma->dma_pool, hw, phys); + return NULL; + } + + dma_async_tx_descriptor_init(&desc->txd, chan); + desc->txd.tx_submit = ioat2_tx_submit_unlock; + desc->hw = hw; + desc->txd.phys = phys; + return desc; +} + +static void ioat2_free_ring_ent(struct ioat_ring_ent *desc, struct dma_chan *chan) +{ + struct ioatdma_device *dma; + + dma = to_ioatdma_device(chan->device); + pci_pool_free(dma->dma_pool, desc->hw, desc->txd.phys); + kmem_cache_free(ioat2_cache, desc); +} + +static struct ioat_ring_ent **ioat2_alloc_ring(struct dma_chan *c, int order, gfp_t flags) +{ + struct ioat_ring_ent **ring; + int descs = 1 << order; + int i; + + if (order > ioat_get_max_alloc_order()) + return NULL; + + /* allocate the array to hold the software ring */ + ring = kcalloc(descs, sizeof(*ring), flags); + if (!ring) + return NULL; + for (i = 0; i < descs; i++) { + ring[i] = ioat2_alloc_ring_ent(c, flags); + if (!ring[i]) { + while (i--) + ioat2_free_ring_ent(ring[i], c); + kfree(ring); + return NULL; + } + set_desc_id(ring[i], i); + } + + /* link descs */ + for (i = 0; i < descs-1; i++) { + struct ioat_ring_ent *next = ring[i+1]; + struct ioat_dma_descriptor *hw = ring[i]->hw; + + hw->next = next->txd.phys; + } + ring[i]->hw->next = ring[0]->txd.phys; + + return ring; +} + +void ioat2_free_chan_resources(struct dma_chan *c); + +/* ioat2_alloc_chan_resources - allocate/initialize ioat2 descriptor ring + * @chan: channel to be initialized + */ +int ioat2_alloc_chan_resources(struct dma_chan *c) +{ + struct ioat2_dma_chan *ioat = to_ioat2_chan(c); + struct ioat_chan_common *chan = &ioat->base; + struct ioat_ring_ent **ring; + u64 status; + int order; + int i = 0; + + /* have we already been set up? */ + if (ioat->ring) + return 1 << ioat->alloc_order; + + /* Setup register to interrupt and write completion status on error */ + writew(IOAT_CHANCTRL_RUN, chan->reg_base + IOAT_CHANCTRL_OFFSET); + + /* 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); + if (!chan->completion) + return -ENOMEM; + + 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); + + order = ioat_get_alloc_order(); + ring = ioat2_alloc_ring(c, order, GFP_KERNEL); + if (!ring) + return -ENOMEM; + + spin_lock_bh(&chan->cleanup_lock); + spin_lock_bh(&ioat->prep_lock); + ioat->ring = ring; + ioat->head = 0; + ioat->issued = 0; + ioat->tail = 0; + ioat->alloc_order = order; + set_bit(IOAT_RUN, &chan->state); + spin_unlock_bh(&ioat->prep_lock); + spin_unlock_bh(&chan->cleanup_lock); + + ioat2_start_null_desc(ioat); + + /* check that we got off the ground */ + do { + udelay(1); + status = ioat_chansts(chan); + } while (i++ < 20 && !is_ioat_active(status) && !is_ioat_idle(status)); + + if (is_ioat_active(status) || is_ioat_idle(status)) { + return 1 << ioat->alloc_order; + } else { + u32 chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET); + + dev_WARN(to_dev(chan), + "failed to start channel chanerr: %#x\n", chanerr); + ioat2_free_chan_resources(c); + return -EFAULT; + } +} + +bool reshape_ring(struct ioat2_dma_chan *ioat, int order) +{ + /* reshape differs from normal ring allocation in that we want + * to allocate a new software ring while only + * extending/truncating the hardware ring + */ + struct ioat_chan_common *chan = &ioat->base; + struct dma_chan *c = &chan->common; + const u32 curr_size = ioat2_ring_size(ioat); + const u16 active = ioat2_ring_active(ioat); + const u32 new_size = 1 << order; + struct ioat_ring_ent **ring; + u16 i; + + if (order > ioat_get_max_alloc_order()) + return false; + + /* double check that we have at least 1 free descriptor */ + if (active == curr_size) + return false; + + /* when shrinking, verify that we can hold the current active + * set in the new ring + */ + if (active >= new_size) + return false; + + /* allocate the array to hold the software ring */ + ring = kcalloc(new_size, sizeof(*ring), GFP_NOWAIT); + if (!ring) + return false; + + /* allocate/trim descriptors as needed */ + if (new_size > curr_size) { + /* copy current descriptors to the new ring */ + for (i = 0; i < curr_size; i++) { + u16 curr_idx = (ioat->tail+i) & (curr_size-1); + u16 new_idx = (ioat->tail+i) & (new_size-1); + + ring[new_idx] = ioat->ring[curr_idx]; + set_desc_id(ring[new_idx], new_idx); + } + + /* add new descriptors to the ring */ + for (i = curr_size; i < new_size; i++) { + u16 new_idx = (ioat->tail+i) & (new_size-1); + + ring[new_idx] = ioat2_alloc_ring_ent(c, GFP_NOWAIT); + if (!ring[new_idx]) { + while (i--) { + u16 new_idx = (ioat->tail+i) & (new_size-1); + + ioat2_free_ring_ent(ring[new_idx], c); + } + kfree(ring); + return false; + } + set_desc_id(ring[new_idx], new_idx); + } + + /* hw link new descriptors */ + for (i = curr_size-1; i < new_size; i++) { + u16 new_idx = (ioat->tail+i) & (new_size-1); + struct ioat_ring_ent *next = ring[(new_idx+1) & (new_size-1)]; + struct ioat_dma_descriptor *hw = ring[new_idx]->hw; + + hw->next = next->txd.phys; + } + } else { + struct ioat_dma_descriptor *hw; + struct ioat_ring_ent *next; + + /* copy current descriptors to the new ring, dropping the + * removed descriptors + */ + for (i = 0; i < new_size; i++) { + u16 curr_idx = (ioat->tail+i) & (curr_size-1); + u16 new_idx = (ioat->tail+i) & (new_size-1); + + ring[new_idx] = ioat->ring[curr_idx]; + set_desc_id(ring[new_idx], new_idx); + } + + /* free deleted descriptors */ + for (i = new_size; i < curr_size; i++) { + struct ioat_ring_ent *ent; + + ent = ioat2_get_ring_ent(ioat, ioat->tail+i); + ioat2_free_ring_ent(ent, c); + } + + /* fix up hardware ring */ + hw = ring[(ioat->tail+new_size-1) & (new_size-1)]->hw; + next = ring[(ioat->tail+new_size) & (new_size-1)]; + hw->next = next->txd.phys; + } + + dev_dbg(to_dev(chan), "%s: allocated %d descriptors\n", + __func__, new_size); + + kfree(ioat->ring); + ioat->ring = ring; + ioat->alloc_order = order; + + return true; +} + +/** + * ioat2_check_space_lock - verify space and grab ring producer lock + * @ioat: ioat2,3 channel (ring) to operate on + * @num_descs: allocation length + */ +int ioat2_check_space_lock(struct ioat2_dma_chan *ioat, int num_descs) +{ + struct ioat_chan_common *chan = &ioat->base; + bool retry; + + retry: + spin_lock_bh(&ioat->prep_lock); + /* never allow the last descriptor to be consumed, we need at + * least one free at all times to allow for on-the-fly ring + * resizing. + */ + if (likely(ioat2_ring_space(ioat) > num_descs)) { + dev_dbg(to_dev(chan), "%s: num_descs: %d (%x:%x:%x)\n", + __func__, num_descs, ioat->head, ioat->tail, ioat->issued); + ioat->produce = num_descs; + return 0; /* with ioat->prep_lock held */ + } + retry = test_and_set_bit(IOAT_RESHAPE_PENDING, &chan->state); + spin_unlock_bh(&ioat->prep_lock); + + /* is another cpu already trying to expand the ring? */ + if (retry) + goto retry; + + spin_lock_bh(&chan->cleanup_lock); + spin_lock_bh(&ioat->prep_lock); + retry = reshape_ring(ioat, ioat->alloc_order + 1); + clear_bit(IOAT_RESHAPE_PENDING, &chan->state); + spin_unlock_bh(&ioat->prep_lock); + spin_unlock_bh(&chan->cleanup_lock); + + /* if we were able to expand the ring retry the allocation */ + if (retry) + goto retry; + + if (printk_ratelimit()) + dev_dbg(to_dev(chan), "%s: ring full! num_descs: %d (%x:%x:%x)\n", + __func__, num_descs, ioat->head, ioat->tail, ioat->issued); + + /* progress reclaim in the allocation failure case we may be + * called under bh_disabled so we need to trigger the timer + * event directly + */ + if (time_is_before_jiffies(chan->timer.expires) + && timer_pending(&chan->timer)) { + struct ioatdma_device *device = chan->device; + + mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT); + device->timer_fn((unsigned long) &chan->common); + } + + return -ENOMEM; +} + +struct dma_async_tx_descriptor * +ioat2_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest, + dma_addr_t dma_src, size_t len, unsigned long flags) +{ + struct ioat2_dma_chan *ioat = to_ioat2_chan(c); + struct ioat_dma_descriptor *hw; + struct ioat_ring_ent *desc; + dma_addr_t dst = dma_dest; + dma_addr_t src = dma_src; + size_t total_len = len; + int num_descs, idx, i; + + num_descs = ioat2_xferlen_to_descs(ioat, len); + if (likely(num_descs) && ioat2_check_space_lock(ioat, num_descs) == 0) + idx = ioat->head; + else + return NULL; + i = 0; + do { + size_t copy = min_t(size_t, len, 1 << ioat->xfercap_log); + + desc = ioat2_get_ring_ent(ioat, idx + i); + hw = desc->hw; + + hw->size = copy; + hw->ctl = 0; + hw->src_addr = src; + hw->dst_addr = dst; + + len -= copy; + dst += copy; + src += copy; + dump_desc_dbg(ioat, desc); + } while (++i < num_descs); + + desc->txd.flags = flags; + desc->len = total_len; + hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT); + hw->ctl_f.fence = !!(flags & DMA_PREP_FENCE); + hw->ctl_f.compl_write = 1; + dump_desc_dbg(ioat, desc); + /* we leave the channel locked to ensure in order submission */ + + return &desc->txd; +} + +/** + * ioat2_free_chan_resources - release all the descriptors + * @chan: the channel to be cleaned + */ +void ioat2_free_chan_resources(struct dma_chan *c) +{ + struct ioat2_dma_chan *ioat = to_ioat2_chan(c); + struct ioat_chan_common *chan = &ioat->base; + struct ioatdma_device *device = chan->device; + struct ioat_ring_ent *desc; + const u16 total_descs = 1 << ioat->alloc_order; + int descs; + int i; + + /* Before freeing channel resources first check + * if they have been previously allocated for this channel. + */ + if (!ioat->ring) + return; + + ioat_stop(chan); + device->reset_hw(chan); + + spin_lock_bh(&chan->cleanup_lock); + spin_lock_bh(&ioat->prep_lock); + descs = ioat2_ring_space(ioat); + dev_dbg(to_dev(chan), "freeing %d idle descriptors\n", descs); + for (i = 0; i < descs; i++) { + desc = ioat2_get_ring_ent(ioat, ioat->head + i); + ioat2_free_ring_ent(desc, c); + } + + if (descs < total_descs) + dev_err(to_dev(chan), "Freeing %d in use descriptors!\n", + total_descs - descs); + + for (i = 0; i < total_descs - descs; i++) { + desc = ioat2_get_ring_ent(ioat, ioat->tail + i); + dump_desc_dbg(ioat, desc); + ioat2_free_ring_ent(desc, c); + } + + kfree(ioat->ring); + ioat->ring = NULL; + ioat->alloc_order = 0; + pci_pool_free(device->completion_pool, chan->completion, + chan->completion_dma); + spin_unlock_bh(&ioat->prep_lock); + spin_unlock_bh(&chan->cleanup_lock); + + chan->last_completion = 0; + chan->completion_dma = 0; + ioat->dmacount = 0; +} + +static ssize_t ring_size_show(struct dma_chan *c, char *page) +{ + struct ioat2_dma_chan *ioat = to_ioat2_chan(c); + + return sprintf(page, "%d\n", (1 << ioat->alloc_order) & ~1); +} +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 ioat2_dma_chan *ioat = to_ioat2_chan(c); + + /* ...taken outside the lock, no need to be precise */ + return sprintf(page, "%d\n", ioat2_ring_active(ioat)); +} +static struct ioat_sysfs_entry ring_active_attr = __ATTR_RO(ring_active); + +static struct attribute *ioat2_attrs[] = { + &ring_size_attr.attr, + &ring_active_attr.attr, + &ioat_cap_attr.attr, + &ioat_version_attr.attr, + NULL, +}; + +struct kobj_type ioat2_ktype = { + .sysfs_ops = &ioat_sysfs_ops, + .default_attrs = ioat2_attrs, +}; + +int ioat2_dma_probe(struct ioatdma_device *device, int dca) +{ + struct pci_dev *pdev = device->pdev; + struct dma_device *dma; + struct dma_chan *c; + struct ioat_chan_common *chan; + int err; + + device->enumerate_channels = ioat2_enumerate_channels; + device->reset_hw = ioat2_reset_hw; + device->cleanup_fn = ioat2_cleanup_event; + device->timer_fn = ioat2_timer_event; + device->self_test = ioat_dma_self_test; + dma = &device->common; + dma->device_prep_dma_memcpy = ioat2_dma_prep_memcpy_lock; + dma->device_issue_pending = ioat2_issue_pending; + dma->device_alloc_chan_resources = ioat2_alloc_chan_resources; + dma->device_free_chan_resources = ioat2_free_chan_resources; + dma->device_tx_status = ioat_dma_tx_status; + + err = ioat_probe(device); + if (err) + return err; + + list_for_each_entry(c, &dma->channels, device_node) { + chan = to_chan_common(c); + writel(IOAT_DCACTRL_CMPL_WRITE_ENABLE | IOAT_DMA_DCA_ANY_CPU, + chan->reg_base + IOAT_DCACTRL_OFFSET); + } + + err = ioat_register(device); + if (err) + return err; + + ioat_kobject_add(device, &ioat2_ktype); + + if (dca) + device->dca = ioat2_dca_init(pdev, device->reg_base); + + return err; +} |