- 根目录:
- drivers
- block
- rsxx
- dma.c
/*
* 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);
}