--- /dev/null
+/*
+* Filename: dma.c
+*
+*
+* Authors: Joshua Morris <josh.h.morris@us.ibm.com>
+* Philip Kelleher <pjk1939@linux.vnet.ibm.com>
+*
+* (C) Copyright 2013 IBM Corporation
+*
+* This program is free software; you can redistribute it and/or
+* modify it under the terms of the GNU General Public License as
+* published by the Free Software Foundation; either version 2 of the
+* License, or (at your option) any later version.
+*
+* This program is distributed in the hope that it will be useful, but
+* WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+* General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with this program; if not, write to the Free Software Foundation,
+* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#include <linux/slab.h>
+#include "rsxx_priv.h"
+
+struct rsxx_dma {
+ struct list_head list;
+ u8 cmd;
+ unsigned int laddr; /* Logical address */
+ struct {
+ u32 off;
+ u32 cnt;
+ } sub_page;
+ dma_addr_t dma_addr;
+ struct page *page;
+ unsigned int pg_off; /* Page Offset */
+ rsxx_dma_cb cb;
+ void *cb_data;
+};
+
+/* This timeout is used to detect a stalled DMA channel */
+#define DMA_ACTIVITY_TIMEOUT msecs_to_jiffies(10000)
+
+struct hw_status {
+ u8 status;
+ u8 tag;
+ __le16 count;
+ __le32 _rsvd2;
+ __le64 _rsvd3;
+} __packed;
+
+enum rsxx_dma_status {
+ DMA_SW_ERR = 0x1,
+ DMA_HW_FAULT = 0x2,
+ DMA_CANCELLED = 0x4,
+};
+
+struct hw_cmd {
+ u8 command;
+ u8 tag;
+ u8 _rsvd;
+ u8 sub_page; /* Bit[0:2]: 512byte offset */
+ /* Bit[4:6]: 512byte count */
+ __le32 device_addr;
+ __le64 host_addr;
+} __packed;
+
+enum rsxx_hw_cmd {
+ HW_CMD_BLK_DISCARD = 0x70,
+ HW_CMD_BLK_WRITE = 0x80,
+ HW_CMD_BLK_READ = 0xC0,
+ HW_CMD_BLK_RECON_READ = 0xE0,
+};
+
+enum rsxx_hw_status {
+ HW_STATUS_CRC = 0x01,
+ HW_STATUS_HARD_ERR = 0x02,
+ HW_STATUS_SOFT_ERR = 0x04,
+ HW_STATUS_FAULT = 0x08,
+};
+
+static struct kmem_cache *rsxx_dma_pool;
+
+struct dma_tracker {
+ int next_tag;
+ struct rsxx_dma *dma;
+};
+
+#define DMA_TRACKER_LIST_SIZE8 (sizeof(struct dma_tracker_list) + \
+ (sizeof(struct dma_tracker) * RSXX_MAX_OUTSTANDING_CMDS))
+
+struct dma_tracker_list {
+ spinlock_t lock;
+ int head;
+ struct dma_tracker list[0];
+};
+
+
+/*----------------- Misc Utility Functions -------------------*/
+static unsigned int rsxx_addr8_to_laddr(u64 addr8, struct rsxx_cardinfo *card)
+{
+ unsigned long long tgt_addr8;
+
+ tgt_addr8 = ((addr8 >> card->_stripe.upper_shift) &
+ card->_stripe.upper_mask) |
+ ((addr8) & card->_stripe.lower_mask);
+ do_div(tgt_addr8, RSXX_HW_BLK_SIZE);
+ return tgt_addr8;
+}
+
+static unsigned int rsxx_get_dma_tgt(struct rsxx_cardinfo *card, u64 addr8)
+{
+ unsigned int tgt;
+
+ tgt = (addr8 >> card->_stripe.target_shift) & card->_stripe.target_mask;
+
+ return tgt;
+}
+
+void rsxx_dma_queue_reset(struct rsxx_cardinfo *card)
+{
+ /* Reset all DMA Command/Status Queues */
+ iowrite32(DMA_QUEUE_RESET, card->regmap + RESET);
+}
+
+static unsigned int get_dma_size(struct rsxx_dma *dma)
+{
+ if (dma->sub_page.cnt)
+ return dma->sub_page.cnt << 9;
+ else
+ return RSXX_HW_BLK_SIZE;
+}
+
+
+/*----------------- DMA Tracker -------------------*/
+static void set_tracker_dma(struct dma_tracker_list *trackers,
+ int tag,
+ struct rsxx_dma *dma)
+{
+ trackers->list[tag].dma = dma;
+}
+
+static struct rsxx_dma *get_tracker_dma(struct dma_tracker_list *trackers,
+ int tag)
+{
+ return trackers->list[tag].dma;
+}
+
+static int pop_tracker(struct dma_tracker_list *trackers)
+{
+ int tag;
+
+ spin_lock(&trackers->lock);
+ tag = trackers->head;
+ if (tag != -1) {
+ trackers->head = trackers->list[tag].next_tag;
+ trackers->list[tag].next_tag = -1;
+ }
+ spin_unlock(&trackers->lock);
+
+ return tag;
+}
+
+static void push_tracker(struct dma_tracker_list *trackers, int tag)
+{
+ spin_lock(&trackers->lock);
+ trackers->list[tag].next_tag = trackers->head;
+ trackers->head = tag;
+ trackers->list[tag].dma = NULL;
+ spin_unlock(&trackers->lock);
+}
+
+
+/*----------------- Interrupt Coalescing -------------*/
+/*
+ * Interrupt Coalescing Register Format:
+ * Interrupt Timer (64ns units) [15:0]
+ * Interrupt Count [24:16]
+ * Reserved [31:25]
+*/
+#define INTR_COAL_LATENCY_MASK (0x0000ffff)
+
+#define INTR_COAL_COUNT_SHIFT 16
+#define INTR_COAL_COUNT_BITS 9
+#define INTR_COAL_COUNT_MASK (((1 << INTR_COAL_COUNT_BITS) - 1) << \
+ INTR_COAL_COUNT_SHIFT)
+#define INTR_COAL_LATENCY_UNITS_NS 64
+
+
+static u32 dma_intr_coal_val(u32 mode, u32 count, u32 latency)
+{
+ u32 latency_units = latency / INTR_COAL_LATENCY_UNITS_NS;
+
+ if (mode == RSXX_INTR_COAL_DISABLED)
+ return 0;
+
+ return ((count << INTR_COAL_COUNT_SHIFT) & INTR_COAL_COUNT_MASK) |
+ (latency_units & INTR_COAL_LATENCY_MASK);
+
+}
+
+static void dma_intr_coal_auto_tune(struct rsxx_cardinfo *card)
+{
+ int i;
+ u32 q_depth = 0;
+ u32 intr_coal;
+
+ if (card->config.data.intr_coal.mode != RSXX_INTR_COAL_AUTO_TUNE ||
+ unlikely(card->eeh_state))
+ return;
+
+ for (i = 0; i < card->n_targets; i++)
+ q_depth += atomic_read(&card->ctrl[i].stats.hw_q_depth);
+
+ intr_coal = dma_intr_coal_val(card->config.data.intr_coal.mode,
+ q_depth / 2,
+ card->config.data.intr_coal.latency);
+ iowrite32(intr_coal, card->regmap + INTR_COAL);
+}
+
+/*----------------- RSXX DMA Handling -------------------*/
+static void rsxx_free_dma(struct rsxx_dma_ctrl *ctrl, struct rsxx_dma *dma)
+{
+ if (dma->cmd != HW_CMD_BLK_DISCARD) {
+ if (!pci_dma_mapping_error(ctrl->card->dev, dma->dma_addr)) {
+ pci_unmap_page(ctrl->card->dev, dma->dma_addr,
+ get_dma_size(dma),
+ dma->cmd == HW_CMD_BLK_WRITE ?
+ PCI_DMA_TODEVICE :
+ PCI_DMA_FROMDEVICE);
+ }
+ }
+
+ kmem_cache_free(rsxx_dma_pool, dma);
+}
+
+static void rsxx_complete_dma(struct rsxx_dma_ctrl *ctrl,
+ struct rsxx_dma *dma,
+ unsigned int status)
+{
+ if (status & DMA_SW_ERR)
+ ctrl->stats.dma_sw_err++;
+ if (status & DMA_HW_FAULT)
+ ctrl->stats.dma_hw_fault++;
+ if (status & DMA_CANCELLED)
+ ctrl->stats.dma_cancelled++;
+
+ if (dma->cb)
+ dma->cb(ctrl->card, dma->cb_data, status ? 1 : 0);
+
+ rsxx_free_dma(ctrl, dma);
+}
+
+int rsxx_cleanup_dma_queue(struct rsxx_dma_ctrl *ctrl,
+ struct list_head *q, unsigned int done)
+{
+ struct rsxx_dma *dma;
+ struct rsxx_dma *tmp;
+ int cnt = 0;
+
+ list_for_each_entry_safe(dma, tmp, q, list) {
+ list_del(&dma->list);
+ if (done & COMPLETE_DMA)
+ rsxx_complete_dma(ctrl, dma, DMA_CANCELLED);
+ else
+ rsxx_free_dma(ctrl, dma);
+ cnt++;
+ }
+
+ return cnt;
+}
+
+static void rsxx_requeue_dma(struct rsxx_dma_ctrl *ctrl,
+ struct rsxx_dma *dma)
+{
+ /*
+ * Requeued DMAs go to the front of the queue so they are issued
+ * first.
+ */
+ spin_lock_bh(&ctrl->queue_lock);
+ ctrl->stats.sw_q_depth++;
+ list_add(&dma->list, &ctrl->queue);
+ spin_unlock_bh(&ctrl->queue_lock);
+}
+
+static void rsxx_handle_dma_error(struct rsxx_dma_ctrl *ctrl,
+ struct rsxx_dma *dma,
+ u8 hw_st)
+{
+ unsigned int status = 0;
+ int requeue_cmd = 0;
+
+ dev_dbg(CARD_TO_DEV(ctrl->card),
+ "Handling DMA error(cmd x%02x, laddr x%08x st:x%02x)\n",
+ dma->cmd, dma->laddr, hw_st);
+
+ if (hw_st & HW_STATUS_CRC)
+ ctrl->stats.crc_errors++;
+ if (hw_st & HW_STATUS_HARD_ERR)
+ ctrl->stats.hard_errors++;
+ if (hw_st & HW_STATUS_SOFT_ERR)
+ ctrl->stats.soft_errors++;
+
+ switch (dma->cmd) {
+ case HW_CMD_BLK_READ:
+ if (hw_st & (HW_STATUS_CRC | HW_STATUS_HARD_ERR)) {
+ if (ctrl->card->scrub_hard) {
+ dma->cmd = HW_CMD_BLK_RECON_READ;
+ requeue_cmd = 1;
+ ctrl->stats.reads_retried++;
+ } else {
+ status |= DMA_HW_FAULT;
+ ctrl->stats.reads_failed++;
+ }
+ } else if (hw_st & HW_STATUS_FAULT) {
+ status |= DMA_HW_FAULT;
+ ctrl->stats.reads_failed++;
+ }
+
+ break;
+ case HW_CMD_BLK_RECON_READ:
+ if (hw_st & (HW_STATUS_CRC | HW_STATUS_HARD_ERR)) {
+ /* Data could not be reconstructed. */
+ status |= DMA_HW_FAULT;
+ ctrl->stats.reads_failed++;
+ }
+
+ break;
+ case HW_CMD_BLK_WRITE:
+ status |= DMA_HW_FAULT;
+ ctrl->stats.writes_failed++;
+
+ break;
+ case HW_CMD_BLK_DISCARD:
+ status |= DMA_HW_FAULT;
+ ctrl->stats.discards_failed++;
+
+ break;
+ default:
+ dev_err(CARD_TO_DEV(ctrl->card),
+ "Unknown command in DMA!(cmd: x%02x "
+ "laddr x%08x st: x%02x\n",
+ dma->cmd, dma->laddr, hw_st);
+ status |= DMA_SW_ERR;
+
+ break;
+ }
+
+ if (requeue_cmd)
+ rsxx_requeue_dma(ctrl, dma);
+ else
+ rsxx_complete_dma(ctrl, dma, status);
+}
+
+static void dma_engine_stalled(unsigned long data)
+{
+ struct rsxx_dma_ctrl *ctrl = (struct rsxx_dma_ctrl *)data;
+ int cnt;
+
+ if (atomic_read(&ctrl->stats.hw_q_depth) == 0 ||
+ unlikely(ctrl->card->eeh_state))
+ return;
+
+ if (ctrl->cmd.idx != ioread32(ctrl->regmap + SW_CMD_IDX)) {
+ /*
+ * The dma engine was stalled because the SW_CMD_IDX write
+ * was lost. Issue it again to recover.
+ */
+ dev_warn(CARD_TO_DEV(ctrl->card),
+ "SW_CMD_IDX write was lost, re-writing...\n");
+ iowrite32(ctrl->cmd.idx, ctrl->regmap + SW_CMD_IDX);
+ mod_timer(&ctrl->activity_timer,
+ jiffies + DMA_ACTIVITY_TIMEOUT);
+ } else {
+ dev_warn(CARD_TO_DEV(ctrl->card),
+ "DMA channel %d has stalled, faulting interface.\n",
+ ctrl->id);
+ ctrl->card->dma_fault = 1;
+
+ /* Clean up the DMA queue */
+ spin_lock(&ctrl->queue_lock);
+ cnt = rsxx_cleanup_dma_queue(ctrl, &ctrl->queue, COMPLETE_DMA);
+ spin_unlock(&ctrl->queue_lock);
+
+ cnt += rsxx_dma_cancel(ctrl);
+
+ if (cnt)
+ dev_info(CARD_TO_DEV(ctrl->card),
+ "Freed %d queued DMAs on channel %d\n",
+ cnt, ctrl->id);
+ }
+}
+
+static void rsxx_issue_dmas(struct rsxx_dma_ctrl *ctrl)
+{
+ struct rsxx_dma *dma;
+ int tag;
+ int cmds_pending = 0;
+ struct hw_cmd *hw_cmd_buf;
+ int dir;
+
+ hw_cmd_buf = ctrl->cmd.buf;
+
+ if (unlikely(ctrl->card->halt) ||
+ unlikely(ctrl->card->eeh_state))
+ return;
+
+ while (1) {
+ spin_lock_bh(&ctrl->queue_lock);
+ if (list_empty(&ctrl->queue)) {
+ spin_unlock_bh(&ctrl->queue_lock);
+ break;
+ }
+ spin_unlock_bh(&ctrl->queue_lock);
+
+ tag = pop_tracker(ctrl->trackers);
+ if (tag == -1)
+ break;
+
+ spin_lock_bh(&ctrl->queue_lock);
+ dma = list_entry(ctrl->queue.next, struct rsxx_dma, list);
+ list_del(&dma->list);
+ ctrl->stats.sw_q_depth--;
+ spin_unlock_bh(&ctrl->queue_lock);
+
+ /*
+ * This will catch any DMAs that slipped in right before the
+ * fault, but was queued after all the other DMAs were
+ * cancelled.
+ */
+ if (unlikely(ctrl->card->dma_fault)) {
+ push_tracker(ctrl->trackers, tag);
+ rsxx_complete_dma(ctrl, dma, DMA_CANCELLED);
+ continue;
+ }
+
+ if (dma->cmd != HW_CMD_BLK_DISCARD) {
+ if (dma->cmd == HW_CMD_BLK_WRITE)
+ dir = PCI_DMA_TODEVICE;
+ else
+ dir = PCI_DMA_FROMDEVICE;
+
+ /*
+ * The function pci_map_page is placed here because we
+ * can only, by design, issue up to 255 commands to the
+ * hardware at one time per DMA channel. So the maximum
+ * amount of mapped memory would be 255 * 4 channels *
+ * 4096 Bytes which is less than 2GB, the limit of a x8
+ * Non-HWWD PCIe slot. This way the pci_map_page
+ * function should never fail because of a lack of
+ * mappable memory.
+ */
+ dma->dma_addr = pci_map_page(ctrl->card->dev, dma->page,
+ dma->pg_off, dma->sub_page.cnt << 9, dir);
+ if (pci_dma_mapping_error(ctrl->card->dev, dma->dma_addr)) {
+ push_tracker(ctrl->trackers, tag);
+ rsxx_complete_dma(ctrl, dma, DMA_CANCELLED);
+ continue;
+ }
+ }
+
+ set_tracker_dma(ctrl->trackers, tag, dma);
+ hw_cmd_buf[ctrl->cmd.idx].command = dma->cmd;
+ hw_cmd_buf[ctrl->cmd.idx].tag = tag;
+ hw_cmd_buf[ctrl->cmd.idx]._rsvd = 0;
+ hw_cmd_buf[ctrl->cmd.idx].sub_page =
+ ((dma->sub_page.cnt & 0x7) << 4) |
+ (dma->sub_page.off & 0x7);
+
+ hw_cmd_buf[ctrl->cmd.idx].device_addr =
+ cpu_to_le32(dma->laddr);
+
+ hw_cmd_buf[ctrl->cmd.idx].host_addr =
+ cpu_to_le64(dma->dma_addr);
+
+ dev_dbg(CARD_TO_DEV(ctrl->card),
+ "Issue DMA%d(laddr %d tag %d) to idx %d\n",
+ ctrl->id, dma->laddr, tag, ctrl->cmd.idx);
+
+ ctrl->cmd.idx = (ctrl->cmd.idx + 1) & RSXX_CS_IDX_MASK;
+ cmds_pending++;
+
+ if (dma->cmd == HW_CMD_BLK_WRITE)
+ ctrl->stats.writes_issued++;
+ else if (dma->cmd == HW_CMD_BLK_DISCARD)
+ ctrl->stats.discards_issued++;
+ else
+ ctrl->stats.reads_issued++;
+ }
+
+ /* Let HW know we've queued commands. */
+ if (cmds_pending) {
+ atomic_add(cmds_pending, &ctrl->stats.hw_q_depth);
+ mod_timer(&ctrl->activity_timer,
+ jiffies + DMA_ACTIVITY_TIMEOUT);
+
+ if (unlikely(ctrl->card->eeh_state)) {
+ del_timer_sync(&ctrl->activity_timer);
+ return;
+ }
+
+ iowrite32(ctrl->cmd.idx, ctrl->regmap + SW_CMD_IDX);
+ }
+}
+
+static void rsxx_dma_done(struct rsxx_dma_ctrl *ctrl)
+{
+ struct rsxx_dma *dma;
+ unsigned long flags;
+ u16 count;
+ u8 status;
+ u8 tag;
+ struct hw_status *hw_st_buf;
+
+ hw_st_buf = ctrl->status.buf;
+
+ if (unlikely(ctrl->card->halt) ||
+ unlikely(ctrl->card->dma_fault) ||
+ unlikely(ctrl->card->eeh_state))
+ return;
+
+ count = le16_to_cpu(hw_st_buf[ctrl->status.idx].count);
+
+ while (count == ctrl->e_cnt) {
+ /*
+ * The read memory-barrier is necessary to keep aggressive
+ * processors/optimizers (such as the PPC Apple G5) from
+ * reordering the following status-buffer tag & status read
+ * *before* the count read on subsequent iterations of the
+ * loop!
+ */
+ rmb();
+
+ status = hw_st_buf[ctrl->status.idx].status;
+ tag = hw_st_buf[ctrl->status.idx].tag;
+
+ dma = get_tracker_dma(ctrl->trackers, tag);
+ if (dma == NULL) {
+ spin_lock_irqsave(&ctrl->card->irq_lock, flags);
+ rsxx_disable_ier(ctrl->card, CR_INTR_DMA_ALL);
+ spin_unlock_irqrestore(&ctrl->card->irq_lock, flags);
+
+ dev_err(CARD_TO_DEV(ctrl->card),
+ "No tracker for tag %d "
+ "(idx %d id %d)\n",
+ tag, ctrl->status.idx, ctrl->id);
+ return;
+ }
+
+ dev_dbg(CARD_TO_DEV(ctrl->card),
+ "Completing DMA%d"
+ "(laddr x%x tag %d st: x%x cnt: x%04x) from idx %d.\n",
+ ctrl->id, dma->laddr, tag, status, count,
+ ctrl->status.idx);
+
+ atomic_dec(&ctrl->stats.hw_q_depth);
+
+ mod_timer(&ctrl->activity_timer,
+ jiffies + DMA_ACTIVITY_TIMEOUT);
+
+ if (status)
+ rsxx_handle_dma_error(ctrl, dma, status);
+ else
+ rsxx_complete_dma(ctrl, dma, 0);
+
+ push_tracker(ctrl->trackers, tag);
+
+ ctrl->status.idx = (ctrl->status.idx + 1) &
+ RSXX_CS_IDX_MASK;
+ ctrl->e_cnt++;
+
+ count = le16_to_cpu(hw_st_buf[ctrl->status.idx].count);
+ }
+
+ dma_intr_coal_auto_tune(ctrl->card);
+
+ if (atomic_read(&ctrl->stats.hw_q_depth) == 0)
+ del_timer_sync(&ctrl->activity_timer);
+
+ spin_lock_irqsave(&ctrl->card->irq_lock, flags);
+ rsxx_enable_ier(ctrl->card, CR_INTR_DMA(ctrl->id));
+ spin_unlock_irqrestore(&ctrl->card->irq_lock, flags);
+
+ spin_lock_bh(&ctrl->queue_lock);
+ if (ctrl->stats.sw_q_depth)
+ queue_work(ctrl->issue_wq, &ctrl->issue_dma_work);
+ spin_unlock_bh(&ctrl->queue_lock);
+}
+
+static void rsxx_schedule_issue(struct work_struct *work)
+{
+ struct rsxx_dma_ctrl *ctrl;
+
+ ctrl = container_of(work, struct rsxx_dma_ctrl, issue_dma_work);
+
+ mutex_lock(&ctrl->work_lock);
+ rsxx_issue_dmas(ctrl);
+ mutex_unlock(&ctrl->work_lock);
+}
+
+static void rsxx_schedule_done(struct work_struct *work)
+{
+ struct rsxx_dma_ctrl *ctrl;
+
+ ctrl = container_of(work, struct rsxx_dma_ctrl, dma_done_work);
+
+ mutex_lock(&ctrl->work_lock);
+ rsxx_dma_done(ctrl);
+ mutex_unlock(&ctrl->work_lock);
+}
+
+static int rsxx_queue_discard(struct rsxx_cardinfo *card,
+ struct list_head *q,
+ unsigned int laddr,
+ rsxx_dma_cb cb,
+ void *cb_data)
+{
+ struct rsxx_dma *dma;
+
+ dma = kmem_cache_alloc(rsxx_dma_pool, GFP_KERNEL);
+ if (!dma)
+ return -ENOMEM;
+
+ dma->cmd = HW_CMD_BLK_DISCARD;
+ dma->laddr = laddr;
+ dma->dma_addr = 0;
+ dma->sub_page.off = 0;
+ dma->sub_page.cnt = 0;
+ dma->page = NULL;
+ dma->pg_off = 0;
+ dma->cb = cb;
+ dma->cb_data = cb_data;
+
+ dev_dbg(CARD_TO_DEV(card), "Queuing[D] laddr %x\n", dma->laddr);
+
+ list_add_tail(&dma->list, q);
+
+ return 0;
+}
+
+static int rsxx_queue_dma(struct rsxx_cardinfo *card,
+ struct list_head *q,
+ int dir,
+ unsigned int dma_off,
+ unsigned int dma_len,
+ unsigned int laddr,
+ struct page *page,
+ unsigned int pg_off,
+ rsxx_dma_cb cb,
+ void *cb_data)
+{
+ struct rsxx_dma *dma;
+
+ dma = kmem_cache_alloc(rsxx_dma_pool, GFP_KERNEL);
+ if (!dma)
+ return -ENOMEM;
+
+ dma->cmd = dir ? HW_CMD_BLK_WRITE : HW_CMD_BLK_READ;
+ dma->laddr = laddr;
+ dma->sub_page.off = (dma_off >> 9);
+ dma->sub_page.cnt = (dma_len >> 9);
+ dma->page = page;
+ dma->pg_off = pg_off;
+ dma->cb = cb;
+ dma->cb_data = cb_data;
+
+ dev_dbg(CARD_TO_DEV(card),
+ "Queuing[%c] laddr %x off %d cnt %d page %p pg_off %d\n",
+ dir ? 'W' : 'R', dma->laddr, dma->sub_page.off,
+ dma->sub_page.cnt, dma->page, dma->pg_off);
+
+ /* Queue the DMA */
+ list_add_tail(&dma->list, q);
+
+ return 0;
+}
+
+int rsxx_dma_queue_bio(struct rsxx_cardinfo *card,
+ struct bio *bio,
+ atomic_t *n_dmas,
+ rsxx_dma_cb cb,
+ void *cb_data)
+{
+ struct list_head dma_list[RSXX_MAX_TARGETS];
+ struct bio_vec bvec;
+ struct bvec_iter iter;
+ unsigned long long addr8;
+ unsigned int laddr;
+ unsigned int bv_len;
+ unsigned int bv_off;
+ unsigned int dma_off;
+ unsigned int dma_len;
+ int dma_cnt[RSXX_MAX_TARGETS];
+ int tgt;
+ int st;
+ int i;
+
+ addr8 = bio->bi_iter.bi_sector << 9; /* sectors are 512 bytes */
+ atomic_set(n_dmas, 0);
+
+ for (i = 0; i < card->n_targets; i++) {
+ INIT_LIST_HEAD(&dma_list[i]);
+ dma_cnt[i] = 0;
+ }
+
+ if (bio->bi_rw & REQ_DISCARD) {
+ bv_len = bio->bi_iter.bi_size;
+
+ while (bv_len > 0) {
+ tgt = rsxx_get_dma_tgt(card, addr8);
+ laddr = rsxx_addr8_to_laddr(addr8, card);
+
+ st = rsxx_queue_discard(card, &dma_list[tgt], laddr,
+ cb, cb_data);
+ if (st)
+ goto bvec_err;
+
+ dma_cnt[tgt]++;
+ atomic_inc(n_dmas);
+ addr8 += RSXX_HW_BLK_SIZE;
+ bv_len -= RSXX_HW_BLK_SIZE;
+ }
+ } else {
+ bio_for_each_segment(bvec, bio, iter) {
+ bv_len = bvec.bv_len;
+ bv_off = bvec.bv_offset;
+
+ while (bv_len > 0) {
+ tgt = rsxx_get_dma_tgt(card, addr8);
+ laddr = rsxx_addr8_to_laddr(addr8, card);
+ dma_off = addr8 & RSXX_HW_BLK_MASK;
+ dma_len = min(bv_len,
+ RSXX_HW_BLK_SIZE - dma_off);
+
+ st = rsxx_queue_dma(card, &dma_list[tgt],
+ bio_data_dir(bio),
+ dma_off, dma_len,
+ laddr, bvec.bv_page,
+ bv_off, cb, cb_data);
+ if (st)
+ goto bvec_err;
+
+ dma_cnt[tgt]++;
+ atomic_inc(n_dmas);
+ addr8 += dma_len;
+ bv_off += dma_len;
+ bv_len -= dma_len;
+ }
+ }
+ }
+
+ for (i = 0; i < card->n_targets; i++) {
+ if (!list_empty(&dma_list[i])) {
+ spin_lock_bh(&card->ctrl[i].queue_lock);
+ card->ctrl[i].stats.sw_q_depth += dma_cnt[i];
+ list_splice_tail(&dma_list[i], &card->ctrl[i].queue);
+ spin_unlock_bh(&card->ctrl[i].queue_lock);
+
+ queue_work(card->ctrl[i].issue_wq,
+ &card->ctrl[i].issue_dma_work);
+ }
+ }
+
+ return 0;
+
+bvec_err:
+ for (i = 0; i < card->n_targets; i++)
+ rsxx_cleanup_dma_queue(&card->ctrl[i], &dma_list[i],
+ FREE_DMA);
+
+ return st;
+}
+
+
+/*----------------- DMA Engine Initialization & Setup -------------------*/
+int rsxx_hw_buffers_init(struct pci_dev *dev, struct rsxx_dma_ctrl *ctrl)
+{
+ ctrl->status.buf = pci_alloc_consistent(dev, STATUS_BUFFER_SIZE8,
+ &ctrl->status.dma_addr);
+ ctrl->cmd.buf = pci_alloc_consistent(dev, COMMAND_BUFFER_SIZE8,
+ &ctrl->cmd.dma_addr);
+ if (ctrl->status.buf == NULL || ctrl->cmd.buf == NULL)
+ return -ENOMEM;
+
+ memset(ctrl->status.buf, 0xac, STATUS_BUFFER_SIZE8);
+ iowrite32(lower_32_bits(ctrl->status.dma_addr),
+ ctrl->regmap + SB_ADD_LO);
+ iowrite32(upper_32_bits(ctrl->status.dma_addr),
+ ctrl->regmap + SB_ADD_HI);
+
+ memset(ctrl->cmd.buf, 0x83, COMMAND_BUFFER_SIZE8);
+ iowrite32(lower_32_bits(ctrl->cmd.dma_addr), ctrl->regmap + CB_ADD_LO);
+ iowrite32(upper_32_bits(ctrl->cmd.dma_addr), ctrl->regmap + CB_ADD_HI);
+
+ ctrl->status.idx = ioread32(ctrl->regmap + HW_STATUS_CNT);
+ if (ctrl->status.idx > RSXX_MAX_OUTSTANDING_CMDS) {
+ dev_crit(&dev->dev, "Failed reading status cnt x%x\n",
+ ctrl->status.idx);
+ return -EINVAL;
+ }
+ iowrite32(ctrl->status.idx, ctrl->regmap + HW_STATUS_CNT);
+ iowrite32(ctrl->status.idx, ctrl->regmap + SW_STATUS_CNT);
+
+ ctrl->cmd.idx = ioread32(ctrl->regmap + HW_CMD_IDX);
+ if (ctrl->cmd.idx > RSXX_MAX_OUTSTANDING_CMDS) {
+ dev_crit(&dev->dev, "Failed reading cmd cnt x%x\n",
+ ctrl->status.idx);
+ return -EINVAL;
+ }
+ iowrite32(ctrl->cmd.idx, ctrl->regmap + HW_CMD_IDX);
+ iowrite32(ctrl->cmd.idx, ctrl->regmap + SW_CMD_IDX);
+
+ return 0;
+}
+
+static int rsxx_dma_ctrl_init(struct pci_dev *dev,
+ struct rsxx_dma_ctrl *ctrl)
+{
+ int i;
+ int st;
+
+ memset(&ctrl->stats, 0, sizeof(ctrl->stats));
+
+ ctrl->trackers = vmalloc(DMA_TRACKER_LIST_SIZE8);
+ if (!ctrl->trackers)
+ return -ENOMEM;
+
+ ctrl->trackers->head = 0;
+ for (i = 0; i < RSXX_MAX_OUTSTANDING_CMDS; i++) {
+ ctrl->trackers->list[i].next_tag = i + 1;
+ ctrl->trackers->list[i].dma = NULL;
+ }
+ ctrl->trackers->list[RSXX_MAX_OUTSTANDING_CMDS-1].next_tag = -1;
+ spin_lock_init(&ctrl->trackers->lock);
+
+ spin_lock_init(&ctrl->queue_lock);
+ mutex_init(&ctrl->work_lock);
+ INIT_LIST_HEAD(&ctrl->queue);
+
+ setup_timer(&ctrl->activity_timer, dma_engine_stalled,
+ (unsigned long)ctrl);
+
+ ctrl->issue_wq = alloc_ordered_workqueue(DRIVER_NAME"_issue", 0);
+ if (!ctrl->issue_wq)
+ return -ENOMEM;
+
+ ctrl->done_wq = alloc_ordered_workqueue(DRIVER_NAME"_done", 0);
+ if (!ctrl->done_wq)
+ return -ENOMEM;
+
+ INIT_WORK(&ctrl->issue_dma_work, rsxx_schedule_issue);
+ INIT_WORK(&ctrl->dma_done_work, rsxx_schedule_done);
+
+ st = rsxx_hw_buffers_init(dev, ctrl);
+ if (st)
+ return st;
+
+ return 0;
+}
+
+static int rsxx_dma_stripe_setup(struct rsxx_cardinfo *card,
+ unsigned int stripe_size8)
+{
+ if (!is_power_of_2(stripe_size8)) {
+ dev_err(CARD_TO_DEV(card),
+ "stripe_size is NOT a power of 2!\n");
+ return -EINVAL;
+ }
+
+ card->_stripe.lower_mask = stripe_size8 - 1;
+
+ card->_stripe.upper_mask = ~(card->_stripe.lower_mask);
+ card->_stripe.upper_shift = ffs(card->n_targets) - 1;
+
+ card->_stripe.target_mask = card->n_targets - 1;
+ card->_stripe.target_shift = ffs(stripe_size8) - 1;
+
+ dev_dbg(CARD_TO_DEV(card), "_stripe.lower_mask = x%016llx\n",
+ card->_stripe.lower_mask);
+ dev_dbg(CARD_TO_DEV(card), "_stripe.upper_shift = x%016llx\n",
+ card->_stripe.upper_shift);
+ dev_dbg(CARD_TO_DEV(card), "_stripe.upper_mask = x%016llx\n",
+ card->_stripe.upper_mask);
+ dev_dbg(CARD_TO_DEV(card), "_stripe.target_mask = x%016llx\n",
+ card->_stripe.target_mask);
+ dev_dbg(CARD_TO_DEV(card), "_stripe.target_shift = x%016llx\n",
+ card->_stripe.target_shift);
+
+ return 0;
+}
+
+int rsxx_dma_configure(struct rsxx_cardinfo *card)
+{
+ u32 intr_coal;
+
+ intr_coal = dma_intr_coal_val(card->config.data.intr_coal.mode,
+ card->config.data.intr_coal.count,
+ card->config.data.intr_coal.latency);
+ iowrite32(intr_coal, card->regmap + INTR_COAL);
+
+ return rsxx_dma_stripe_setup(card, card->config.data.stripe_size);
+}
+
+int rsxx_dma_setup(struct rsxx_cardinfo *card)
+{
+ unsigned long flags;
+ int st;
+ int i;
+
+ dev_info(CARD_TO_DEV(card),
+ "Initializing %d DMA targets\n",
+ card->n_targets);
+
+ /* Regmap is divided up into 4K chunks. One for each DMA channel */
+ for (i = 0; i < card->n_targets; i++)
+ card->ctrl[i].regmap = card->regmap + (i * 4096);
+
+ card->dma_fault = 0;
+
+ /* Reset the DMA queues */
+ rsxx_dma_queue_reset(card);
+
+ /************* Setup DMA Control *************/
+ for (i = 0; i < card->n_targets; i++) {
+ st = rsxx_dma_ctrl_init(card->dev, &card->ctrl[i]);
+ if (st)
+ goto failed_dma_setup;
+
+ card->ctrl[i].card = card;
+ card->ctrl[i].id = i;
+ }
+
+ card->scrub_hard = 1;
+
+ if (card->config_valid)
+ rsxx_dma_configure(card);
+
+ /* Enable the interrupts after all setup has completed. */
+ for (i = 0; i < card->n_targets; i++) {
+ spin_lock_irqsave(&card->irq_lock, flags);
+ rsxx_enable_ier_and_isr(card, CR_INTR_DMA(i));
+ spin_unlock_irqrestore(&card->irq_lock, flags);
+ }
+
+ return 0;
+
+failed_dma_setup:
+ for (i = 0; i < card->n_targets; i++) {
+ struct rsxx_dma_ctrl *ctrl = &card->ctrl[i];
+
+ if (ctrl->issue_wq) {
+ destroy_workqueue(ctrl->issue_wq);
+ ctrl->issue_wq = NULL;
+ }
+
+ if (ctrl->done_wq) {
+ destroy_workqueue(ctrl->done_wq);
+ ctrl->done_wq = NULL;
+ }
+
+ if (ctrl->trackers)
+ vfree(ctrl->trackers);
+
+ if (ctrl->status.buf)
+ pci_free_consistent(card->dev, STATUS_BUFFER_SIZE8,
+ ctrl->status.buf,
+ ctrl->status.dma_addr);
+ if (ctrl->cmd.buf)
+ pci_free_consistent(card->dev, COMMAND_BUFFER_SIZE8,
+ ctrl->cmd.buf, ctrl->cmd.dma_addr);
+ }
+
+ return st;
+}
+
+int rsxx_dma_cancel(struct rsxx_dma_ctrl *ctrl)
+{
+ struct rsxx_dma *dma;
+ int i;
+ int cnt = 0;
+
+ /* Clean up issued DMAs */
+ for (i = 0; i < RSXX_MAX_OUTSTANDING_CMDS; i++) {
+ dma = get_tracker_dma(ctrl->trackers, i);
+ if (dma) {
+ atomic_dec(&ctrl->stats.hw_q_depth);
+ rsxx_complete_dma(ctrl, dma, DMA_CANCELLED);
+ push_tracker(ctrl->trackers, i);
+ cnt++;
+ }
+ }
+
+ return cnt;
+}
+
+void rsxx_dma_destroy(struct rsxx_cardinfo *card)
+{
+ struct rsxx_dma_ctrl *ctrl;
+ int i;
+
+ for (i = 0; i < card->n_targets; i++) {
+ ctrl = &card->ctrl[i];
+
+ if (ctrl->issue_wq) {
+ destroy_workqueue(ctrl->issue_wq);
+ ctrl->issue_wq = NULL;
+ }
+
+ if (ctrl->done_wq) {
+ destroy_workqueue(ctrl->done_wq);
+ ctrl->done_wq = NULL;
+ }
+
+ if (timer_pending(&ctrl->activity_timer))
+ del_timer_sync(&ctrl->activity_timer);
+
+ /* Clean up the DMA queue */
+ spin_lock_bh(&ctrl->queue_lock);
+ rsxx_cleanup_dma_queue(ctrl, &ctrl->queue, COMPLETE_DMA);
+ spin_unlock_bh(&ctrl->queue_lock);
+
+ rsxx_dma_cancel(ctrl);
+
+ vfree(ctrl->trackers);
+
+ pci_free_consistent(card->dev, STATUS_BUFFER_SIZE8,
+ ctrl->status.buf, ctrl->status.dma_addr);
+ pci_free_consistent(card->dev, COMMAND_BUFFER_SIZE8,
+ ctrl->cmd.buf, ctrl->cmd.dma_addr);
+ }
+}
+
+int rsxx_eeh_save_issued_dmas(struct rsxx_cardinfo *card)
+{
+ int i;
+ int j;
+ int cnt;
+ struct rsxx_dma *dma;
+ struct list_head *issued_dmas;
+
+ issued_dmas = kzalloc(sizeof(*issued_dmas) * card->n_targets,
+ GFP_KERNEL);
+ if (!issued_dmas)
+ return -ENOMEM;
+
+ for (i = 0; i < card->n_targets; i++) {
+ INIT_LIST_HEAD(&issued_dmas[i]);
+ cnt = 0;
+ for (j = 0; j < RSXX_MAX_OUTSTANDING_CMDS; j++) {
+ dma = get_tracker_dma(card->ctrl[i].trackers, j);
+ if (dma == NULL)
+ continue;
+
+ if (dma->cmd == HW_CMD_BLK_WRITE)
+ card->ctrl[i].stats.writes_issued--;
+ else if (dma->cmd == HW_CMD_BLK_DISCARD)
+ card->ctrl[i].stats.discards_issued--;
+ else
+ card->ctrl[i].stats.reads_issued--;
+
+ if (dma->cmd != HW_CMD_BLK_DISCARD) {
+ pci_unmap_page(card->dev, dma->dma_addr,
+ get_dma_size(dma),
+ dma->cmd == HW_CMD_BLK_WRITE ?
+ PCI_DMA_TODEVICE :
+ PCI_DMA_FROMDEVICE);
+ }
+
+ list_add_tail(&dma->list, &issued_dmas[i]);
+ push_tracker(card->ctrl[i].trackers, j);
+ cnt++;
+ }
+
+ spin_lock_bh(&card->ctrl[i].queue_lock);
+ list_splice(&issued_dmas[i], &card->ctrl[i].queue);
+
+ atomic_sub(cnt, &card->ctrl[i].stats.hw_q_depth);
+ card->ctrl[i].stats.sw_q_depth += cnt;
+ card->ctrl[i].e_cnt = 0;
+ spin_unlock_bh(&card->ctrl[i].queue_lock);
+ }
+
+ kfree(issued_dmas);
+
+ return 0;
+}
+
+int rsxx_dma_init(void)
+{
+ rsxx_dma_pool = KMEM_CACHE(rsxx_dma, SLAB_HWCACHE_ALIGN);
+ if (!rsxx_dma_pool)
+ return -ENOMEM;
+
+ return 0;
+}
+
+
+void rsxx_dma_cleanup(void)
+{
+ kmem_cache_destroy(rsxx_dma_pool);
+}
+
Code Review / kvmfornfv.git / blobdiff