- 根目录:
- drivers
- dma
- pch_dma.c
/*
* Topcliff PCH DMA controller driver
* Copyright (c) 2010 Intel Corporation
* Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/pch_dma.h>
#define DRV_NAME "pch-dma"
#define DMA_CTL0_DISABLE 0x0
#define DMA_CTL0_SG 0x1
#define DMA_CTL0_ONESHOT 0x2
#define DMA_CTL0_MODE_MASK_BITS 0x3
#define DMA_CTL0_DIR_SHIFT_BITS 2
#define DMA_CTL0_BITS_PER_CH 4
#define DMA_CTL2_START_SHIFT_BITS 8
#define DMA_CTL2_IRQ_ENABLE_MASK ((1UL << DMA_CTL2_START_SHIFT_BITS) - 1)
#define DMA_STATUS_IDLE 0x0
#define DMA_STATUS_DESC_READ 0x1
#define DMA_STATUS_WAIT 0x2
#define DMA_STATUS_ACCESS 0x3
#define DMA_STATUS_BITS_PER_CH 2
#define DMA_STATUS_MASK_BITS 0x3
#define DMA_STATUS_SHIFT_BITS 16
#define DMA_STATUS_IRQ(x) (0x1 << (x))
#define DMA_STATUS0_ERR(x) (0x1 << ((x) + 8))
#define DMA_STATUS2_ERR(x) (0x1 << (x))
#define DMA_DESC_WIDTH_SHIFT_BITS 12
#define DMA_DESC_WIDTH_1_BYTE (0x3 << DMA_DESC_WIDTH_SHIFT_BITS)
#define DMA_DESC_WIDTH_2_BYTES (0x2 << DMA_DESC_WIDTH_SHIFT_BITS)
#define DMA_DESC_WIDTH_4_BYTES (0x0 << DMA_DESC_WIDTH_SHIFT_BITS)
#define DMA_DESC_MAX_COUNT_1_BYTE 0x3FF
#define DMA_DESC_MAX_COUNT_2_BYTES 0x3FF
#define DMA_DESC_MAX_COUNT_4_BYTES 0x7FF
#define DMA_DESC_END_WITHOUT_IRQ 0x0
#define DMA_DESC_END_WITH_IRQ 0x1
#define DMA_DESC_FOLLOW_WITHOUT_IRQ 0x2
#define DMA_DESC_FOLLOW_WITH_IRQ 0x3
#define MAX_CHAN_NR 12
#define DMA_MASK_CTL0_MODE 0x33333333
#define DMA_MASK_CTL2_MODE 0x00003333
static unsigned int init_nr_desc_per_channel = 64;
module_param(init_nr_desc_per_channel, uint, 0644);
MODULE_PARM_DESC(init_nr_desc_per_channel,
"initial descriptors per channel (default: 64)");
struct pch_dma_desc_regs {
u32 dev_addr;
u32 mem_addr;
u32 size;
u32 next;
};
struct pch_dma_regs {
u32 dma_ctl0;
u32 dma_ctl1;
u32 dma_ctl2;
u32 dma_ctl3;
u32 dma_sts0;
u32 dma_sts1;
u32 dma_sts2;
u32 reserved3;
struct pch_dma_desc_regs desc[MAX_CHAN_NR];
};
struct pch_dma_desc {
struct pch_dma_desc_regs regs;
struct dma_async_tx_descriptor txd;
struct list_head desc_node;
struct list_head tx_list;
};
struct pch_dma_chan {
struct dma_chan chan;
void __iomem *membase;
enum dma_transfer_direction dir;
struct tasklet_struct tasklet;
unsigned long err_status;
spinlock_t lock;
dma_cookie_t completed_cookie;
struct list_head active_list;
struct list_head queue;
struct list_head free_list;
unsigned int descs_allocated;
};
#define PDC_DEV_ADDR 0x00
#define PDC_MEM_ADDR 0x04
#define PDC_SIZE 0x08
#define PDC_NEXT 0x0C
#define channel_readl(pdc, name) \
readl((pdc)->membase + PDC_##name)
#define channel_writel(pdc, name, val) \
writel((val), (pdc)->membase + PDC_##name)
struct pch_dma {
struct dma_device dma;
void __iomem *membase;
struct pci_pool *pool;
struct pch_dma_regs regs;
struct pch_dma_desc_regs ch_regs[MAX_CHAN_NR];
struct pch_dma_chan channels[MAX_CHAN_NR];
};
#define PCH_DMA_CTL0 0x00
#define PCH_DMA_CTL1 0x04
#define PCH_DMA_CTL2 0x08
#define PCH_DMA_CTL3 0x0C
#define PCH_DMA_STS0 0x10
#define PCH_DMA_STS1 0x14
#define PCH_DMA_STS2 0x18
#define dma_readl(pd, name) \
readl((pd)->membase + PCH_DMA_##name)
#define dma_writel(pd, name, val) \
writel((val), (pd)->membase + PCH_DMA_##name)
static inline
struct pch_dma_desc *to_pd_desc(struct dma_async_tx_descriptor *txd)
{
return container_of(txd, struct pch_dma_desc, txd);
}
static inline struct pch_dma_chan *to_pd_chan(struct dma_chan *chan)
{
return container_of(chan, struct pch_dma_chan, chan);
}
static inline struct pch_dma *to_pd(struct dma_device *ddev)
{
return container_of(ddev, struct pch_dma, dma);
}
static inline struct device *chan2dev(struct dma_chan *chan)
{
return &chan->dev->device;
}
static inline struct device *chan2parent(struct dma_chan *chan)
{
return chan->dev->device.parent;
}
static inline
struct pch_dma_desc *pdc_first_active(struct pch_dma_chan *pd_chan)
{
return list_first_entry(&pd_chan->active_list,
struct pch_dma_desc, desc_node);
}
static inline
struct pch_dma_desc *pdc_first_queued(struct pch_dma_chan *pd_chan)
{
return list_first_entry(&pd_chan->queue,
struct pch_dma_desc, desc_node);
}
static void pdc_enable_irq(struct dma_chan *chan, int enable)
{
struct pch_dma *pd = to_pd(chan->device);
u32 val;
int pos;
if (chan->chan_id < 8)
pos = chan->chan_id;
else
pos = chan->chan_id + 8;
val = dma_readl(pd, CTL2);
if (enable)
val |= 0x1 << pos;
else
val &= ~(0x1 << pos);
dma_writel(pd, CTL2, val);
dev_dbg(chan2dev(chan), "pdc_enable_irq: chan %d -> %x\n",
chan->chan_id, val);
}
static void pdc_set_dir(struct dma_chan *chan)
{
struct pch_dma_chan *pd_chan = to_pd_chan(chan);
struct pch_dma *pd = to_pd(chan->device);
u32 val;
u32 mask_mode;
u32 mask_ctl;
if (chan->chan_id < 8) {
val = dma_readl(pd, CTL0);
mask_mode = DMA_CTL0_MODE_MASK_BITS <<
(DMA_CTL0_BITS_PER_CH * chan->chan_id);
mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
(DMA_CTL0_BITS_PER_CH * chan->chan_id));
val &= mask_mode;
if (pd_chan->dir == DMA_MEM_TO_DEV)
val |= 0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +
DMA_CTL0_DIR_SHIFT_BITS);
else
val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +
DMA_CTL0_DIR_SHIFT_BITS));
val |= mask_ctl;
dma_writel(pd, CTL0, val);
} else {
int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */
val = dma_readl(pd, CTL3);
mask_mode = DMA_CTL0_MODE_MASK_BITS <<
(DMA_CTL0_BITS_PER_CH * ch);
mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
(DMA_CTL0_BITS_PER_CH * ch));
val &= mask_mode;
if (pd_chan->dir == DMA_MEM_TO_DEV)
val |= 0x1 << (DMA_CTL0_BITS_PER_CH * ch +
DMA_CTL0_DIR_SHIFT_BITS);
else
val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * ch +
DMA_CTL0_DIR_SHIFT_BITS));
val |= mask_ctl;
dma_writel(pd, CTL3, val);
}
dev_dbg(chan2dev(chan), "pdc_set_dir: chan %d -> %x\n",
chan->chan_id, val);
}
static void pdc_set_mode(struct dma_chan *chan, u32 mode)
{
struct pch_dma *pd = to_pd(chan->device);
u32 val;
u32 mask_ctl;
u32 mask_dir;
if (chan->chan_id < 8) {
mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
(DMA_CTL0_BITS_PER_CH * chan->chan_id));
mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +\
DMA_CTL0_DIR_SHIFT_BITS);
val = dma_readl(pd, CTL0);
val &= mask_dir;
val |= mode << (DMA_CTL0_BITS_PER_CH * chan->chan_id);
val |= mask_ctl;
dma_writel(pd, CTL0, val);
} else {
int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */
mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
(DMA_CTL0_BITS_PER_CH * ch));
mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * ch +\
DMA_CTL0_DIR_SHIFT_BITS);
val = dma_readl(pd, CTL3);
val &= mask_dir;
val |= mode << (DMA_CTL0_BITS_PER_CH * ch);
val |= mask_ctl;
dma_writel(pd, CTL3, val);
}
dev_dbg(chan2dev(chan), "pdc_set_mode: chan %d -> %x\n",
chan->chan_id, val);
}
static u32 pdc_get_status0(struct pch_dma_chan *pd_chan)
{
struct pch_dma *pd = to_pd(pd_chan->chan.device);
u32 val;
val = dma_readl(pd, STS0);
return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +
DMA_STATUS_BITS_PER_CH * pd_chan->chan.chan_id));
}
static u32 pdc_get_status2(struct pch_dma_chan *pd_chan)
{
struct pch_dma *pd = to_pd(pd_chan->chan.device);
u32 val;
val = dma_readl(pd, STS2);
return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +
DMA_STATUS_BITS_PER_CH * (pd_chan->chan.chan_id - 8)));
}
static bool pdc_is_idle(struct pch_dma_chan *pd_chan)
{
u32 sts;
if (pd_chan->chan.chan_id < 8)
sts = pdc_get_status0(pd_chan);
else
sts = pdc_get_status2(pd_chan);
if (sts == DMA_STATUS_IDLE)
return true;
else
return false;
}
static void pdc_dostart(struct pch_dma_chan *pd_chan, struct pch_dma_desc* desc)
{
if (!pdc_is_idle(pd_chan)) {
dev_err(chan2dev(&pd_chan->chan),
"BUG: Attempt to start non-idle channel\n");
return;
}
dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> dev_addr: %x\n",
pd_chan->chan.chan_id, desc->regs.dev_addr);
dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> mem_addr: %x\n",
pd_chan->chan.chan_id, desc->regs.mem_addr);
dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> size: %x\n",
pd_chan->chan.chan_id, desc->regs.size);
dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> next: %x\n",
pd_chan->chan.chan_id, desc->regs.next);
if (list_empty(&desc->tx_list)) {
channel_writel(pd_chan, DEV_ADDR, desc->regs.dev_addr);
channel_writel(pd_chan, MEM_ADDR, desc->regs.mem_addr);
channel_writel(pd_chan, SIZE, desc->regs.size);
channel_writel(pd_chan, NEXT, desc->regs.next);
pdc_set_mode(&pd_chan->chan, DMA_CTL0_ONESHOT);
} else {
channel_writel(pd_chan, NEXT, desc->txd.phys);
pdc_set_mode(&pd_chan->chan, DMA_CTL0_SG);
}
}
static void pdc_chain_complete(struct pch_dma_chan *pd_chan,
struct pch_dma_desc *desc)
{
struct dma_async_tx_descriptor *txd = &desc->txd;
dma_async_tx_callback callback = txd->callback;
void *param = txd->callback_param;
list_splice_init(&desc->tx_list, &pd_chan->free_list);
list_move(&desc->desc_node, &pd_chan->free_list);
if (callback)
callback(param);
}
static void pdc_complete_all(struct pch_dma_chan *pd_chan)
{
struct pch_dma_desc *desc, *_d;
LIST_HEAD(list);
BUG_ON(!pdc_is_idle(pd_chan));
if (!list_empty(&pd_chan->queue))
pdc_dostart(pd_chan, pdc_first_queued(pd_chan));
list_splice_init(&pd_chan->active_list, &list);
list_splice_init(&pd_chan->queue, &pd_chan->active_list);
list_for_each_entry_safe(desc, _d, &list, desc_node)
pdc_chain_complete(pd_chan, desc);
}
static void pdc_handle_error(struct pch_dma_chan *pd_chan)
{
struct pch_dma_desc *bad_desc;
bad_desc = pdc_first_active(pd_chan);
list_del(&bad_desc->desc_node);
list_splice_init(&pd_chan->queue, pd_chan->active_list.prev);
if (!list_empty(&pd_chan->active_list))
pdc_dostart(pd_chan, pdc_first_active(pd_chan));
dev_crit(chan2dev(&pd_chan->chan), "Bad descriptor submitted\n");
dev_crit(chan2dev(&pd_chan->chan), "descriptor cookie: %d\n",
bad_desc->txd.cookie);
pdc_chain_complete(pd_chan, bad_desc);
}
static void pdc_advance_work(struct pch_dma_chan *pd_chan)
{
if (list_empty(&pd_chan->active_list) ||
list_is_singular(&pd_chan->active_list)) {
pdc_complete_all(pd_chan);
} else {
pdc_chain_complete(pd_chan, pdc_first_active(pd_chan));
pdc_dostart(pd_chan, pdc_first_active(pd_chan));
}
}
static dma_cookie_t pdc_assign_cookie(struct pch_dma_chan *pd_chan,
struct pch_dma_desc *desc)
{
dma_cookie_t cookie = pd_chan->chan.cookie;
if (++cookie < 0)
cookie = 1;
pd_chan->chan.cookie = cookie;
desc->txd.cookie = cookie;
return cookie;
}
static dma_cookie_t pd_tx_submit(struct dma_async_tx_descriptor *txd)
{
struct pch_dma_desc *desc = to_pd_desc(txd);
struct pch_dma_chan *pd_chan = to_pd_chan(txd->chan);
dma_cookie_t cookie;
spin_lock(&pd_chan->lock);
cookie = pdc_assign_cookie(pd_chan, desc);
if (list_empty(&pd_chan->active_list)) {
list_add_tail(&desc->desc_node, &pd_chan->active_list);
pdc_dostart(pd_chan, desc);
} else {
list_add_tail(&desc->desc_node, &pd_chan->queue);
}
spin_unlock(&pd_chan->lock);
return 0;
}
static struct pch_dma_desc *pdc_alloc_desc(struct dma_chan *chan, gfp_t flags)
{
struct pch_dma_desc *desc = NULL;
struct pch_dma *pd = to_pd(chan->device);
dma_addr_t addr;
desc = pci_pool_alloc(pd->pool, flags, &addr);
if (desc) {
memset(desc, 0, sizeof(struct pch_dma_desc));
INIT_LIST_HEAD(&desc->tx_list);
dma_async_tx_descriptor_init(&desc->txd, chan);
desc->txd.tx_submit = pd_tx_submit;
desc->txd.flags = DMA_CTRL_ACK;
desc->txd.phys = addr;
}
return desc;
}
static struct pch_dma_desc *pdc_desc_get(struct pch_dma_chan *pd_chan)
{
struct pch_dma_desc *desc, *_d;
struct pch_dma_desc *ret = NULL;
int i = 0;
spin_lock(&pd_chan->lock);
list_for_each_entry_safe(desc, _d, &pd_chan->free_list, desc_node) {
i++;
if (async_tx_test_ack(&desc->txd)) {
list_del(&desc->desc_node);
ret = desc;
break;
}
dev_dbg(chan2dev(&pd_chan->chan), "desc %p not ACKed\n", desc);
}
spin_unlock(&pd_chan->lock);
dev_dbg(chan2dev(&pd_chan->chan), "scanned %d descriptors\n", i);
if (!ret) {
ret = pdc_alloc_desc(&pd_chan->chan, GFP_NOIO);
if (ret) {
spin_lock(&pd_chan->lock);
pd_chan->descs_allocated++;
spin_unlock(&pd_chan->lock);
} else {
dev_err(chan2dev(&pd_chan->chan),
"failed to alloc desc\n");
}
}
return ret;
}
static void pdc_desc_put(struct pch_dma_chan *pd_chan,
struct pch_dma_desc *desc)
{
if (desc) {
spin_lock(&pd_chan->lock);
list_splice_init(&desc->tx_list, &pd_chan->free_list);
list_add(&desc->desc_node, &pd_chan->free_list);
spin_unlock(&pd_chan->lock);
}
}
static int pd_alloc_chan_resources(struct dma_chan *chan)
{
struct pch_dma_chan *pd_chan = to_pd_chan(chan);
struct pch_dma_desc *desc;
LIST_HEAD(tmp_list);
int i;
if (!pdc_is_idle(pd_chan)) {
dev_dbg(chan2dev(chan), "DMA channel not idle ?\n");
return -EIO;
}
if (!list_empty(&pd_chan->free_list))
return pd_chan->descs_allocated;
for (i = 0; i < init_nr_desc_per_channel; i++) {
desc = pdc_alloc_desc(chan, GFP_KERNEL);
if (!desc) {
dev_warn(chan2dev(chan),
"Only allocated %d initial descriptors\n", i);
break;
}
list_add_tail(&desc->desc_node, &tmp_list);
}
spin_lock_irq(&pd_chan->lock);
list_splice(&tmp_list, &pd_chan->free_list);
pd_chan->descs_allocated = i;
pd_chan->completed_cookie = chan->cookie = 1;
spin_unlock_irq(&pd_chan->lock);
pdc_enable_irq(chan, 1);
return pd_chan->descs_allocated;
}
static void pd_free_chan_resources(struct dma_chan *chan)
{
struct pch_dma_chan *pd_chan = to_pd_chan(chan);
struct pch_dma *pd = to_pd(chan->device);
struct pch_dma_desc *desc, *_d;
LIST_HEAD(tmp_list);
BUG_ON(!pdc_is_idle(pd_chan));
BUG_ON(!list_empty(&pd_chan->active_list));
BUG_ON(!list_empty(&pd_chan->queue));
spin_lock_irq(&pd_chan->lock);
list_splice_init(&pd_chan->free_list, &tmp_list);
pd_chan->descs_allocated = 0;
spin_unlock_irq(&pd_chan->lock);
list_for_each_entry_safe(desc, _d, &tmp_list, desc_node)
pci_pool_free(pd->pool, desc, desc->txd.phys);
pdc_enable_irq(chan, 0);
}
static enum dma_status pd_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
struct dma_tx_state *txstate)
{
struct pch_dma_chan *pd_chan = to_pd_chan(chan);
dma_cookie_t last_used;
dma_cookie_t last_completed;
int ret;
spin_lock_irq(&pd_chan->lock);
last_completed = pd_chan->completed_cookie;
last_used = chan->cookie;
spin_unlock_irq(&pd_chan->lock);
ret = dma_async_is_complete(cookie, last_completed, last_used);
dma_set_tx_state(txstate, last_completed, last_used, 0);
return ret;
}
static void pd_issue_pending(struct dma_chan *chan)
{
struct pch_dma_chan *pd_chan = to_pd_chan(chan);
if (pdc_is_idle(pd_chan)) {
spin_lock(&pd_chan->lock);
pdc_advance_work(pd_chan);
spin_unlock(&pd_chan->lock);
}
}
static struct dma_async_tx_descriptor *pd_prep_slave_sg(struct dma_chan *chan,
struct scatterlist *sgl, unsigned int sg_len,
enum dma_transfer_direction direction, unsigned long flags)
{
struct pch_dma_chan *pd_chan = to_pd_chan(chan);
struct pch_dma_slave *pd_slave = chan->private;
struct pch_dma_desc *first = NULL;
struct pch_dma_desc *prev = NULL;
struct pch_dma_desc *desc = NULL;
struct scatterlist *sg;
dma_addr_t reg;
int i;
if (unlikely(!sg_len)) {
dev_info(chan2dev(chan), "prep_slave_sg: length is zero!\n");
return NULL;
}
if (direction == DMA_DEV_TO_MEM)
reg = pd_slave->rx_reg;
else if (direction == DMA_MEM_TO_DEV)
reg = pd_slave->tx_reg;
else
return NULL;
pd_chan->dir = direction;
pdc_set_dir(chan);
for_each_sg(sgl, sg, sg_len, i) {
desc = pdc_desc_get(pd_chan);
if (!desc)
goto err_desc_get;
desc->regs.dev_addr = reg;
desc->regs.mem_addr = sg_phys(sg);
desc->regs.size = sg_dma_len(sg);
desc->regs.next = DMA_DESC_FOLLOW_WITHOUT_IRQ;
switch (pd_slave->width) {
case PCH_DMA_WIDTH_1_BYTE:
if (desc->regs.size > DMA_DESC_MAX_COUNT_1_BYTE)
goto err_desc_get;
desc->regs.size |= DMA_DESC_WIDTH_1_BYTE;
break;
case PCH_DMA_WIDTH_2_BYTES:
if (desc->regs.size > DMA_DESC_MAX_COUNT_2_BYTES)
goto err_desc_get;
desc->regs.size |= DMA_DESC_WIDTH_2_BYTES;
break;
case PCH_DMA_WIDTH_4_BYTES:
if (desc->regs.size > DMA_DESC_MAX_COUNT_4_BYTES)
goto err_desc_get;
desc->regs.size |= DMA_DESC_WIDTH_4_BYTES;
break;
default:
goto err_desc_get;
}
if (!first) {
first = desc;
} else {
prev->regs.next |= desc->txd.phys;
list_add_tail(&desc->desc_node, &first->tx_list);
}
prev = desc;
}
if (flags & DMA_PREP_INTERRUPT)
desc->regs.next = DMA_DESC_END_WITH_IRQ;
else
desc->regs.next = DMA_DESC_END_WITHOUT_IRQ;
first->txd.cookie = -EBUSY;
desc->txd.flags = flags;
return &first->txd;
err_desc_get:
dev_err(chan2dev(chan), "failed to get desc or wrong parameters\n");
pdc_desc_put(pd_chan, first);
return NULL;
}
static int pd_device_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
unsigned long arg)
{
struct pch_dma_chan *pd_chan = to_pd_chan(chan);
struct pch_dma_desc *desc, *_d;
LIST_HEAD(list);
if (cmd != DMA_TERMINATE_ALL)
return -ENXIO;
spin_lock_irq(&pd_chan->lock);
pdc_set_mode(&pd_chan->chan, DMA_CTL0_DISABLE);
list_splice_init(&pd_chan->active_list, &list);
list_splice_init(&pd_chan->queue, &list);
list_for_each_entry_safe(desc, _d, &list, desc_node)
pdc_chain_complete(pd_chan, desc);
spin_unlock_irq(&pd_chan->lock);
return 0;
}
static void pdc_tasklet(unsigned long data)
{
struct pch_dma_chan *pd_chan = (struct pch_dma_chan *)data;
unsigned long flags;
if (!pdc_is_idle(pd_chan)) {
dev_err(chan2dev(&pd_chan->chan),
"BUG: handle non-idle channel in tasklet\n");
return;
}
spin_lock_irqsave(&pd_chan->lock, flags);
if (test_and_clear_bit(0, &pd_chan->err_status))
pdc_handle_error(pd_chan);
else
pdc_advance_work(pd_chan);
spin_unlock_irqrestore(&pd_chan->lock, flags);
}
static irqreturn_t pd_irq(int irq, void *devid)
{
struct pch_dma *pd = (struct pch_dma *)devid;
struct pch_dma_chan *pd_chan;
u32 sts0;
u32 sts2;
int i;
int ret0 = IRQ_NONE;
int ret2 = IRQ_NONE;
sts0 = dma_readl(pd, STS0);
sts2 = dma_readl(pd, STS2);
dev_dbg(pd->dma.dev, "pd_irq sts0: %x\n", sts0);
for (i = 0; i < pd->dma.chancnt; i++) {
pd_chan = &pd->channels[i];
if (i < 8) {
if (sts0 & DMA_STATUS_IRQ(i)) {
if (sts0 & DMA_STATUS0_ERR(i))
set_bit(0, &pd_chan->err_status);
tasklet_schedule(&pd_chan->tasklet);
ret0 = IRQ_HANDLED;
}
} else {
if (sts2 & DMA_STATUS_IRQ(i - 8)) {
if (sts2 & DMA_STATUS2_ERR(i))
set_bit(0, &pd_chan->err_status);
tasklet_schedule(&pd_chan->tasklet);
ret2 = IRQ_HANDLED;
}
}
}
/* clear interrupt bits in status register */
if (ret0)
dma_writel(pd, STS0, sts0);
if (ret2)
dma_writel(pd, STS2, sts2);
return ret0 | ret2;
}
#ifdef CONFIG_PM
static void pch_dma_save_regs(struct pch_dma *pd)
{
struct pch_dma_chan *pd_chan;
struct dma_chan *chan, *_c;
int i = 0;
pd->regs.dma_ctl0 = dma_readl(pd, CTL0);
pd->regs.dma_ctl1 = dma_readl(pd, CTL1);
pd->regs.dma_ctl2 = dma_readl(pd, CTL2);
pd->regs.dma_ctl3 = dma_readl(pd, CTL3);
list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
pd_chan = to_pd_chan(chan);
pd->ch_regs[i].dev_addr = channel_readl(pd_chan, DEV_ADDR);
pd->ch_regs[i].mem_addr = channel_readl(pd_chan, MEM_ADDR);
pd->ch_regs[i].size = channel_readl(pd_chan, SIZE);
pd->ch_regs[i].next = channel_readl(pd_chan, NEXT);
i++;
}
}
static void pch_dma_restore_regs(struct pch_dma *pd)
{
struct pch_dma_chan *pd_chan;
struct dma_chan *chan, *_c;
int i = 0;
dma_writel(pd, CTL0, pd->regs.dma_ctl0);
dma_writel(pd, CTL1, pd->regs.dma_ctl1);
dma_writel(pd, CTL2, pd->regs.dma_ctl2);
dma_writel(pd, CTL3, pd->regs.dma_ctl3);
list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
pd_chan = to_pd_chan(chan);
channel_writel(pd_chan, DEV_ADDR, pd->ch_regs[i].dev_addr);
channel_writel(pd_chan, MEM_ADDR, pd->ch_regs[i].mem_addr);
channel_writel(pd_chan, SIZE, pd->ch_regs[i].size);
channel_writel(pd_chan, NEXT, pd->ch_regs[i].next);
i++;
}
}
static int pch_dma_suspend(struct pci_dev *pdev, pm_message_t state)
{
struct pch_dma *pd = pci_get_drvdata(pdev);
if (pd)
pch_dma_save_regs(pd);
pci_save_state(pdev);
pci_disable_device(pdev);
pci_set_power_state(pdev, pci_choose_state(pdev, state));
return 0;
}
static int pch_dma_resume(struct pci_dev *pdev)
{
struct pch_dma *pd = pci_get_drvdata(pdev);
int err;
pci_set_power_state(pdev, PCI_D0);
pci_restore_state(pdev);
err = pci_enable_device(pdev);
if (err) {
dev_dbg(&pdev->dev, "failed to enable device\n");
return err;
}
if (pd)
pch_dma_restore_regs(pd);
return 0;
}
#endif
static int __devinit pch_dma_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
struct pch_dma *pd;
struct pch_dma_regs *regs;
unsigned int nr_channels;
int err;
int i;
nr_channels = id->driver_data;
pd = kzalloc(sizeof(*pd), GFP_KERNEL);
if (!pd)
return -ENOMEM;
pci_set_drvdata(pdev, pd);
err = pci_enable_device(pdev);
if (err) {
dev_err(&pdev->dev, "Cannot enable PCI device\n");
goto err_free_mem;
}
if (!(pci_resource_flags(pdev, 1) & IORESOURCE_MEM)) {
dev_err(&pdev->dev, "Cannot find proper base address\n");
goto err_disable_pdev;
}
err = pci_request_regions(pdev, DRV_NAME);
if (err) {
dev_err(&pdev->dev, "Cannot obtain PCI resources\n");
goto err_disable_pdev;
}
err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
if (err) {
dev_err(&pdev->dev, "Cannot set proper DMA config\n");
goto err_free_res;
}
regs = pd->membase = pci_iomap(pdev, 1, 0);
if (!pd->membase) {
dev_err(&pdev->dev, "Cannot map MMIO registers\n");
err = -ENOMEM;
goto err_free_res;
}
pci_set_master(pdev);
err = request_irq(pdev->irq, pd_irq, IRQF_SHARED, DRV_NAME, pd);
if (err) {
dev_err(&pdev->dev, "Failed to request IRQ\n");
goto err_iounmap;
}
pd->pool = pci_pool_create("pch_dma_desc_pool", pdev,
sizeof(struct pch_dma_desc), 4, 0);
if (!pd->pool) {
dev_err(&pdev->dev, "Failed to alloc DMA descriptors\n");
err = -ENOMEM;
goto err_free_irq;
}
pd->dma.dev = &pdev->dev;
INIT_LIST_HEAD(&pd->dma.channels);
for (i = 0; i < nr_channels; i++) {
struct pch_dma_chan *pd_chan = &pd->channels[i];
pd_chan->chan.device = &pd->dma;
pd_chan->chan.cookie = 1;
pd_chan->membase = ®s->desc[i];
spin_lock_init(&pd_chan->lock);
INIT_LIST_HEAD(&pd_chan->active_list);
INIT_LIST_HEAD(&pd_chan->queue);
INIT_LIST_HEAD(&pd_chan->free_list);
tasklet_init(&pd_chan->tasklet, pdc_tasklet,
(unsigned long)pd_chan);
list_add_tail(&pd_chan->chan.device_node, &pd->dma.channels);
}
dma_cap_zero(pd->dma.cap_mask);
dma_cap_set(DMA_PRIVATE, pd->dma.cap_mask);
dma_cap_set(DMA_SLAVE, pd->dma.cap_mask);
pd->dma.device_alloc_chan_resources = pd_alloc_chan_resources;
pd->dma.device_free_chan_resources = pd_free_chan_resources;
pd->dma.device_tx_status = pd_tx_status;
pd->dma.device_issue_pending = pd_issue_pending;
pd->dma.device_prep_slave_sg = pd_prep_slave_sg;
pd->dma.device_control = pd_device_control;
err = dma_async_device_register(&pd->dma);
if (err) {
dev_err(&pdev->dev, "Failed to register DMA device\n");
goto err_free_pool;
}
return 0;
err_free_pool:
pci_pool_destroy(pd->pool);
err_free_irq:
free_irq(pdev->irq, pd);
err_iounmap:
pci_iounmap(pdev, pd->membase);
err_free_res:
pci_release_regions(pdev);
err_disable_pdev:
pci_disable_device(pdev);
err_free_mem:
return err;
}
static void __devexit pch_dma_remove(struct pci_dev *pdev)
{
struct pch_dma *pd = pci_get_drvdata(pdev);
struct pch_dma_chan *pd_chan;
struct dma_chan *chan, *_c;
if (pd) {
dma_async_device_unregister(&pd->dma);
list_for_each_entry_safe(chan, _c, &pd->dma.channels,
device_node) {
pd_chan = to_pd_chan(chan);
tasklet_disable(&pd_chan->tasklet);
tasklet_kill(&pd_chan->tasklet);
}
pci_pool_destroy(pd->pool);
free_irq(pdev->irq, pd);
pci_iounmap(pdev, pd->membase);
pci_release_regions(pdev);
pci_disable_device(pdev);
kfree(pd);
}
}
/* PCI Device ID of DMA device */
#define PCI_VENDOR_ID_ROHM 0x10DB
#define PCI_DEVICE_ID_EG20T_PCH_DMA_8CH 0x8810
#define PCI_DEVICE_ID_EG20T_PCH_DMA_4CH 0x8815
#define PCI_DEVICE_ID_ML7213_DMA1_8CH 0x8026
#define PCI_DEVICE_ID_ML7213_DMA2_8CH 0x802B
#define PCI_DEVICE_ID_ML7213_DMA3_4CH 0x8034
#define PCI_DEVICE_ID_ML7213_DMA4_12CH 0x8032
#define PCI_DEVICE_ID_ML7223_DMA1_4CH 0x800B
#define PCI_DEVICE_ID_ML7223_DMA2_4CH 0x800E
#define PCI_DEVICE_ID_ML7223_DMA3_4CH 0x8017
#define PCI_DEVICE_ID_ML7223_DMA4_4CH 0x803B
#define PCI_DEVICE_ID_ML7831_DMA1_8CH 0x8810
#define PCI_DEVICE_ID_ML7831_DMA2_4CH 0x8815
DEFINE_PCI_DEVICE_TABLE(pch_dma_id_table) = {
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_8CH), 8 },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_4CH), 4 },
{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA1_8CH), 8}, /* UART Video */
{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA2_8CH), 8}, /* PCMIF SPI */
{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA3_4CH), 4}, /* FPGA */
{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA4_12CH), 12}, /* I2S */
{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA1_4CH), 4}, /* UART */
{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA2_4CH), 4}, /* Video SPI */
{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA3_4CH), 4}, /* Security */
{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA4_4CH), 4}, /* FPGA */
{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA1_8CH), 8}, /* UART */
{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA2_4CH), 4}, /* SPI */
{ 0, },
};
static struct pci_driver pch_dma_driver = {
.name = DRV_NAME,
.id_table = pch_dma_id_table,
.probe = pch_dma_probe,
.remove = __devexit_p(pch_dma_remove),
#ifdef CONFIG_PM
.suspend = pch_dma_suspend,
.resume = pch_dma_resume,
#endif
};
static int __init pch_dma_init(void)
{
return pci_register_driver(&pch_dma_driver);
}
static void __exit pch_dma_exit(void)
{
pci_unregister_driver(&pch_dma_driver);
}
module_init(pch_dma_init);
module_exit(pch_dma_exit);
MODULE_DESCRIPTION("Intel EG20T PCH / LAPIS Semicon ML7213/ML7223/ML7831 IOH "
"DMA controller driver");
MODULE_AUTHOR("Yong Wang <yong.y.wang@intel.com>");
MODULE_LICENSE("GPL v2");