+++ /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 (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;
-}
Code Review / kvmfornfv.git / blobdiff