linux/drivers/dma/pch_dma.c
Lars-Peter Clausen cbb796ccd8 dmaengine: Use sg_dma_address instead of sg_phys
dmaengine drivers should always use sg_dma_address instead of sg_phys to get the
addresses for the transfer from a sg element.

To quote Russel King:
	sg_phys(sg) of course has nothing to do with DMA addresses. It's the
	physical address _to the CPU_ of the memory associated with the scatterlist
	entry. That may, or may not have the same value for the DMA engine,
	particularly if IOMMUs are involved.

	And if these drivers are used on ARM, they must be fixed, sooner rather
	than later.  There's patches in the works which will mean we will end up
	with IOMMU support in the DMA mapping later, which means everything I've
	said above will become reality.

The patch has been generated using the following coccinelle patch:
<smpl>
@@
struct scatterlist *sg;
@@
-sg_phys(sg)
+sg_dma_address(sg)
</smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-05-11 12:04:38 +05:30

1049 lines
26 KiB
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>
#include "dmaengine.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;
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 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 = dma_cookie_assign(txd);
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;
dma_cookie_init(chan);
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);
enum dma_status ret;
spin_lock_irq(&pd_chan->lock);
ret = dma_cookie_status(chan, cookie, txstate);
spin_unlock_irq(&pd_chan->lock);
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,
void *context)
{
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_dma_address(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;
dma_cookie_init(&pd_chan->chan);
pd_chan->membase = &regs->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");