linux/drivers/dma/coh901318.c
Linus Walleij 058276303d DMAENGINE: extend the control command to include an arg
This adds an argument to the DMAengine control function, so that
we can later provide control commands that need some external data
passed in through an argument akin to the ioctl() operation
prototype.

[dan.j.williams@intel.com: fix up some missed conversions]
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-05-17 16:30:42 -07:00

1452 lines
35 KiB
C

/*
* driver/dma/coh901318.c
*
* Copyright (C) 2007-2009 ST-Ericsson
* License terms: GNU General Public License (GPL) version 2
* DMA driver for COH 901 318
* Author: Per Friden <per.friden@stericsson.com>
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h> /* printk() */
#include <linux/fs.h> /* everything... */
#include <linux/slab.h> /* kmalloc() */
#include <linux/dmaengine.h>
#include <linux/platform_device.h>
#include <linux/device.h>
#include <linux/irqreturn.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/uaccess.h>
#include <linux/debugfs.h>
#include <mach/coh901318.h>
#include "coh901318_lli.h"
#define COHC_2_DEV(cohc) (&cohc->chan.dev->device)
#ifdef VERBOSE_DEBUG
#define COH_DBG(x) ({ if (1) x; 0; })
#else
#define COH_DBG(x) ({ if (0) x; 0; })
#endif
struct coh901318_desc {
struct dma_async_tx_descriptor desc;
struct list_head node;
struct scatterlist *sg;
unsigned int sg_len;
struct coh901318_lli *lli;
enum dma_data_direction dir;
unsigned long flags;
};
struct coh901318_base {
struct device *dev;
void __iomem *virtbase;
struct coh901318_pool pool;
struct powersave pm;
struct dma_device dma_slave;
struct dma_device dma_memcpy;
struct coh901318_chan *chans;
struct coh901318_platform *platform;
};
struct coh901318_chan {
spinlock_t lock;
int allocated;
int completed;
int id;
int stopped;
struct work_struct free_work;
struct dma_chan chan;
struct tasklet_struct tasklet;
struct list_head active;
struct list_head queue;
struct list_head free;
unsigned long nbr_active_done;
unsigned long busy;
struct coh901318_base *base;
};
static void coh901318_list_print(struct coh901318_chan *cohc,
struct coh901318_lli *lli)
{
struct coh901318_lli *l = lli;
int i = 0;
while (l) {
dev_vdbg(COHC_2_DEV(cohc), "i %d, lli %p, ctrl 0x%x, src 0x%x"
", dst 0x%x, link 0x%x virt_link_addr 0x%p\n",
i, l, l->control, l->src_addr, l->dst_addr,
l->link_addr, l->virt_link_addr);
i++;
l = l->virt_link_addr;
}
}
#ifdef CONFIG_DEBUG_FS
#define COH901318_DEBUGFS_ASSIGN(x, y) (x = y)
static struct coh901318_base *debugfs_dma_base;
static struct dentry *dma_dentry;
static int coh901318_debugfs_open(struct inode *inode, struct file *file)
{
file->private_data = inode->i_private;
return 0;
}
static int coh901318_debugfs_read(struct file *file, char __user *buf,
size_t count, loff_t *f_pos)
{
u64 started_channels = debugfs_dma_base->pm.started_channels;
int pool_count = debugfs_dma_base->pool.debugfs_pool_counter;
int i;
int ret = 0;
char *dev_buf;
char *tmp;
int dev_size;
dev_buf = kmalloc(4*1024, GFP_KERNEL);
if (dev_buf == NULL)
goto err_kmalloc;
tmp = dev_buf;
tmp += sprintf(tmp, "DMA -- enabled dma channels\n");
for (i = 0; i < debugfs_dma_base->platform->max_channels; i++)
if (started_channels & (1 << i))
tmp += sprintf(tmp, "channel %d\n", i);
tmp += sprintf(tmp, "Pool alloc nbr %d\n", pool_count);
dev_size = tmp - dev_buf;
/* No more to read if offset != 0 */
if (*f_pos > dev_size)
goto out;
if (count > dev_size - *f_pos)
count = dev_size - *f_pos;
if (copy_to_user(buf, dev_buf + *f_pos, count))
ret = -EINVAL;
ret = count;
*f_pos += count;
out:
kfree(dev_buf);
return ret;
err_kmalloc:
return 0;
}
static const struct file_operations coh901318_debugfs_status_operations = {
.owner = THIS_MODULE,
.open = coh901318_debugfs_open,
.read = coh901318_debugfs_read,
};
static int __init init_coh901318_debugfs(void)
{
dma_dentry = debugfs_create_dir("dma", NULL);
(void) debugfs_create_file("status",
S_IFREG | S_IRUGO,
dma_dentry, NULL,
&coh901318_debugfs_status_operations);
return 0;
}
static void __exit exit_coh901318_debugfs(void)
{
debugfs_remove_recursive(dma_dentry);
}
module_init(init_coh901318_debugfs);
module_exit(exit_coh901318_debugfs);
#else
#define COH901318_DEBUGFS_ASSIGN(x, y)
#endif /* CONFIG_DEBUG_FS */
static inline struct coh901318_chan *to_coh901318_chan(struct dma_chan *chan)
{
return container_of(chan, struct coh901318_chan, chan);
}
static inline dma_addr_t
cohc_dev_addr(struct coh901318_chan *cohc)
{
return cohc->base->platform->chan_conf[cohc->id].dev_addr;
}
static inline const struct coh901318_params *
cohc_chan_param(struct coh901318_chan *cohc)
{
return &cohc->base->platform->chan_conf[cohc->id].param;
}
static inline const struct coh_dma_channel *
cohc_chan_conf(struct coh901318_chan *cohc)
{
return &cohc->base->platform->chan_conf[cohc->id];
}
static void enable_powersave(struct coh901318_chan *cohc)
{
unsigned long flags;
struct powersave *pm = &cohc->base->pm;
spin_lock_irqsave(&pm->lock, flags);
pm->started_channels &= ~(1ULL << cohc->id);
if (!pm->started_channels) {
/* DMA no longer intends to access memory */
cohc->base->platform->access_memory_state(cohc->base->dev,
false);
}
spin_unlock_irqrestore(&pm->lock, flags);
}
static void disable_powersave(struct coh901318_chan *cohc)
{
unsigned long flags;
struct powersave *pm = &cohc->base->pm;
spin_lock_irqsave(&pm->lock, flags);
if (!pm->started_channels) {
/* DMA intends to access memory */
cohc->base->platform->access_memory_state(cohc->base->dev,
true);
}
pm->started_channels |= (1ULL << cohc->id);
spin_unlock_irqrestore(&pm->lock, flags);
}
static inline int coh901318_set_ctrl(struct coh901318_chan *cohc, u32 control)
{
int channel = cohc->id;
void __iomem *virtbase = cohc->base->virtbase;
writel(control,
virtbase + COH901318_CX_CTRL +
COH901318_CX_CTRL_SPACING * channel);
return 0;
}
static inline int coh901318_set_conf(struct coh901318_chan *cohc, u32 conf)
{
int channel = cohc->id;
void __iomem *virtbase = cohc->base->virtbase;
writel(conf,
virtbase + COH901318_CX_CFG +
COH901318_CX_CFG_SPACING*channel);
return 0;
}
static int coh901318_start(struct coh901318_chan *cohc)
{
u32 val;
int channel = cohc->id;
void __iomem *virtbase = cohc->base->virtbase;
disable_powersave(cohc);
val = readl(virtbase + COH901318_CX_CFG +
COH901318_CX_CFG_SPACING * channel);
/* Enable channel */
val |= COH901318_CX_CFG_CH_ENABLE;
writel(val, virtbase + COH901318_CX_CFG +
COH901318_CX_CFG_SPACING * channel);
return 0;
}
static int coh901318_prep_linked_list(struct coh901318_chan *cohc,
struct coh901318_lli *lli)
{
int channel = cohc->id;
void __iomem *virtbase = cohc->base->virtbase;
BUG_ON(readl(virtbase + COH901318_CX_STAT +
COH901318_CX_STAT_SPACING*channel) &
COH901318_CX_STAT_ACTIVE);
writel(lli->src_addr,
virtbase + COH901318_CX_SRC_ADDR +
COH901318_CX_SRC_ADDR_SPACING * channel);
writel(lli->dst_addr, virtbase +
COH901318_CX_DST_ADDR +
COH901318_CX_DST_ADDR_SPACING * channel);
writel(lli->link_addr, virtbase + COH901318_CX_LNK_ADDR +
COH901318_CX_LNK_ADDR_SPACING * channel);
writel(lli->control, virtbase + COH901318_CX_CTRL +
COH901318_CX_CTRL_SPACING * channel);
return 0;
}
static dma_cookie_t
coh901318_assign_cookie(struct coh901318_chan *cohc,
struct coh901318_desc *cohd)
{
dma_cookie_t cookie = cohc->chan.cookie;
if (++cookie < 0)
cookie = 1;
cohc->chan.cookie = cookie;
cohd->desc.cookie = cookie;
return cookie;
}
static struct coh901318_desc *
coh901318_desc_get(struct coh901318_chan *cohc)
{
struct coh901318_desc *desc;
if (list_empty(&cohc->free)) {
/* alloc new desc because we're out of used ones
* TODO: alloc a pile of descs instead of just one,
* avoid many small allocations.
*/
desc = kzalloc(sizeof(struct coh901318_desc), GFP_NOWAIT);
if (desc == NULL)
goto out;
INIT_LIST_HEAD(&desc->node);
dma_async_tx_descriptor_init(&desc->desc, &cohc->chan);
} else {
/* Reuse an old desc. */
desc = list_first_entry(&cohc->free,
struct coh901318_desc,
node);
list_del(&desc->node);
/* Initialize it a bit so it's not insane */
desc->sg = NULL;
desc->sg_len = 0;
desc->desc.callback = NULL;
desc->desc.callback_param = NULL;
}
out:
return desc;
}
static void
coh901318_desc_free(struct coh901318_chan *cohc, struct coh901318_desc *cohd)
{
list_add_tail(&cohd->node, &cohc->free);
}
/* call with irq lock held */
static void
coh901318_desc_submit(struct coh901318_chan *cohc, struct coh901318_desc *desc)
{
list_add_tail(&desc->node, &cohc->active);
}
static struct coh901318_desc *
coh901318_first_active_get(struct coh901318_chan *cohc)
{
struct coh901318_desc *d;
if (list_empty(&cohc->active))
return NULL;
d = list_first_entry(&cohc->active,
struct coh901318_desc,
node);
return d;
}
static void
coh901318_desc_remove(struct coh901318_desc *cohd)
{
list_del(&cohd->node);
}
static void
coh901318_desc_queue(struct coh901318_chan *cohc, struct coh901318_desc *desc)
{
list_add_tail(&desc->node, &cohc->queue);
}
static struct coh901318_desc *
coh901318_first_queued(struct coh901318_chan *cohc)
{
struct coh901318_desc *d;
if (list_empty(&cohc->queue))
return NULL;
d = list_first_entry(&cohc->queue,
struct coh901318_desc,
node);
return d;
}
static inline u32 coh901318_get_bytes_in_lli(struct coh901318_lli *in_lli)
{
struct coh901318_lli *lli = in_lli;
u32 bytes = 0;
while (lli) {
bytes += lli->control & COH901318_CX_CTRL_TC_VALUE_MASK;
lli = lli->virt_link_addr;
}
return bytes;
}
/*
* Get the number of bytes left to transfer on this channel,
* it is unwise to call this before stopping the channel for
* absolute measures, but for a rough guess you can still call
* it.
*/
static u32 coh901318_get_bytes_left(struct dma_chan *chan)
{
struct coh901318_chan *cohc = to_coh901318_chan(chan);
struct coh901318_desc *cohd;
struct list_head *pos;
unsigned long flags;
u32 left = 0;
int i = 0;
spin_lock_irqsave(&cohc->lock, flags);
/*
* If there are many queued jobs, we iterate and add the
* size of them all. We take a special look on the first
* job though, since it is probably active.
*/
list_for_each(pos, &cohc->active) {
/*
* The first job in the list will be working on the
* hardware. The job can be stopped but still active,
* so that the transfer counter is somewhere inside
* the buffer.
*/
cohd = list_entry(pos, struct coh901318_desc, node);
if (i == 0) {
struct coh901318_lli *lli;
dma_addr_t ladd;
/* Read current transfer count value */
left = readl(cohc->base->virtbase +
COH901318_CX_CTRL +
COH901318_CX_CTRL_SPACING * cohc->id) &
COH901318_CX_CTRL_TC_VALUE_MASK;
/* See if the transfer is linked... */
ladd = readl(cohc->base->virtbase +
COH901318_CX_LNK_ADDR +
COH901318_CX_LNK_ADDR_SPACING *
cohc->id) &
~COH901318_CX_LNK_LINK_IMMEDIATE;
/* Single transaction */
if (!ladd)
continue;
/*
* Linked transaction, follow the lli, find the
* currently processing lli, and proceed to the next
*/
lli = cohd->lli;
while (lli && lli->link_addr != ladd)
lli = lli->virt_link_addr;
if (lli)
lli = lli->virt_link_addr;
/*
* Follow remaining lli links around to count the total
* number of bytes left
*/
left += coh901318_get_bytes_in_lli(lli);
} else {
left += coh901318_get_bytes_in_lli(cohd->lli);
}
i++;
}
/* Also count bytes in the queued jobs */
list_for_each(pos, &cohc->queue) {
cohd = list_entry(pos, struct coh901318_desc, node);
left += coh901318_get_bytes_in_lli(cohd->lli);
}
spin_unlock_irqrestore(&cohc->lock, flags);
return left;
}
/*
* Pauses a transfer without losing data. Enables power save.
* Use this function in conjunction with coh901318_resume.
*/
static void coh901318_pause(struct dma_chan *chan)
{
u32 val;
unsigned long flags;
struct coh901318_chan *cohc = to_coh901318_chan(chan);
int channel = cohc->id;
void __iomem *virtbase = cohc->base->virtbase;
spin_lock_irqsave(&cohc->lock, flags);
/* Disable channel in HW */
val = readl(virtbase + COH901318_CX_CFG +
COH901318_CX_CFG_SPACING * channel);
/* Stopping infinit transfer */
if ((val & COH901318_CX_CTRL_TC_ENABLE) == 0 &&
(val & COH901318_CX_CFG_CH_ENABLE))
cohc->stopped = 1;
val &= ~COH901318_CX_CFG_CH_ENABLE;
/* Enable twice, HW bug work around */
writel(val, virtbase + COH901318_CX_CFG +
COH901318_CX_CFG_SPACING * channel);
writel(val, virtbase + COH901318_CX_CFG +
COH901318_CX_CFG_SPACING * channel);
/* Spin-wait for it to actually go inactive */
while (readl(virtbase + COH901318_CX_STAT+COH901318_CX_STAT_SPACING *
channel) & COH901318_CX_STAT_ACTIVE)
cpu_relax();
/* Check if we stopped an active job */
if ((readl(virtbase + COH901318_CX_CTRL+COH901318_CX_CTRL_SPACING *
channel) & COH901318_CX_CTRL_TC_VALUE_MASK) > 0)
cohc->stopped = 1;
enable_powersave(cohc);
spin_unlock_irqrestore(&cohc->lock, flags);
}
/* Resumes a transfer that has been stopped via 300_dma_stop(..).
Power save is handled.
*/
static void coh901318_resume(struct dma_chan *chan)
{
u32 val;
unsigned long flags;
struct coh901318_chan *cohc = to_coh901318_chan(chan);
int channel = cohc->id;
spin_lock_irqsave(&cohc->lock, flags);
disable_powersave(cohc);
if (cohc->stopped) {
/* Enable channel in HW */
val = readl(cohc->base->virtbase + COH901318_CX_CFG +
COH901318_CX_CFG_SPACING * channel);
val |= COH901318_CX_CFG_CH_ENABLE;
writel(val, cohc->base->virtbase + COH901318_CX_CFG +
COH901318_CX_CFG_SPACING*channel);
cohc->stopped = 0;
}
spin_unlock_irqrestore(&cohc->lock, flags);
}
bool coh901318_filter_id(struct dma_chan *chan, void *chan_id)
{
unsigned int ch_nr = (unsigned int) chan_id;
if (ch_nr == to_coh901318_chan(chan)->id)
return true;
return false;
}
EXPORT_SYMBOL(coh901318_filter_id);
/*
* DMA channel allocation
*/
static int coh901318_config(struct coh901318_chan *cohc,
struct coh901318_params *param)
{
unsigned long flags;
const struct coh901318_params *p;
int channel = cohc->id;
void __iomem *virtbase = cohc->base->virtbase;
spin_lock_irqsave(&cohc->lock, flags);
if (param)
p = param;
else
p = &cohc->base->platform->chan_conf[channel].param;
/* Clear any pending BE or TC interrupt */
if (channel < 32) {
writel(1 << channel, virtbase + COH901318_BE_INT_CLEAR1);
writel(1 << channel, virtbase + COH901318_TC_INT_CLEAR1);
} else {
writel(1 << (channel - 32), virtbase +
COH901318_BE_INT_CLEAR2);
writel(1 << (channel - 32), virtbase +
COH901318_TC_INT_CLEAR2);
}
coh901318_set_conf(cohc, p->config);
coh901318_set_ctrl(cohc, p->ctrl_lli_last);
spin_unlock_irqrestore(&cohc->lock, flags);
return 0;
}
/* must lock when calling this function
* start queued jobs, if any
* TODO: start all queued jobs in one go
*
* Returns descriptor if queued job is started otherwise NULL.
* If the queue is empty NULL is returned.
*/
static struct coh901318_desc *coh901318_queue_start(struct coh901318_chan *cohc)
{
struct coh901318_desc *cohd;
/*
* start queued jobs, if any
* TODO: transmit all queued jobs in one go
*/
cohd = coh901318_first_queued(cohc);
if (cohd != NULL) {
/* Remove from queue */
coh901318_desc_remove(cohd);
/* initiate DMA job */
cohc->busy = 1;
coh901318_desc_submit(cohc, cohd);
coh901318_prep_linked_list(cohc, cohd->lli);
/* start dma job on this channel */
coh901318_start(cohc);
}
return cohd;
}
/*
* This tasklet is called from the interrupt handler to
* handle each descriptor (DMA job) that is sent to a channel.
*/
static void dma_tasklet(unsigned long data)
{
struct coh901318_chan *cohc = (struct coh901318_chan *) data;
struct coh901318_desc *cohd_fin;
unsigned long flags;
dma_async_tx_callback callback;
void *callback_param;
dev_vdbg(COHC_2_DEV(cohc), "[%s] chan_id %d"
" nbr_active_done %ld\n", __func__,
cohc->id, cohc->nbr_active_done);
spin_lock_irqsave(&cohc->lock, flags);
/* get first active descriptor entry from list */
cohd_fin = coh901318_first_active_get(cohc);
if (cohd_fin == NULL)
goto err;
/* locate callback to client */
callback = cohd_fin->desc.callback;
callback_param = cohd_fin->desc.callback_param;
/* sign this job as completed on the channel */
cohc->completed = cohd_fin->desc.cookie;
/* release the lli allocation and remove the descriptor */
coh901318_lli_free(&cohc->base->pool, &cohd_fin->lli);
/* return desc to free-list */
coh901318_desc_remove(cohd_fin);
coh901318_desc_free(cohc, cohd_fin);
spin_unlock_irqrestore(&cohc->lock, flags);
/* Call the callback when we're done */
if (callback)
callback(callback_param);
spin_lock_irqsave(&cohc->lock, flags);
/*
* If another interrupt fired while the tasklet was scheduling,
* we don't get called twice, so we have this number of active
* counter that keep track of the number of IRQs expected to
* be handled for this channel. If there happen to be more than
* one IRQ to be ack:ed, we simply schedule this tasklet again.
*/
cohc->nbr_active_done--;
if (cohc->nbr_active_done) {
dev_dbg(COHC_2_DEV(cohc), "scheduling tasklet again, new IRQs "
"came in while we were scheduling this tasklet\n");
if (cohc_chan_conf(cohc)->priority_high)
tasklet_hi_schedule(&cohc->tasklet);
else
tasklet_schedule(&cohc->tasklet);
}
spin_unlock_irqrestore(&cohc->lock, flags);
return;
err:
spin_unlock_irqrestore(&cohc->lock, flags);
dev_err(COHC_2_DEV(cohc), "[%s] No active dma desc\n", __func__);
}
/* called from interrupt context */
static void dma_tc_handle(struct coh901318_chan *cohc)
{
/*
* If the channel is not allocated, then we shouldn't have
* any TC interrupts on it.
*/
if (!cohc->allocated) {
dev_err(COHC_2_DEV(cohc), "spurious interrupt from "
"unallocated channel\n");
return;
}
spin_lock(&cohc->lock);
/*
* When we reach this point, at least one queue item
* should have been moved over from cohc->queue to
* cohc->active and run to completion, that is why we're
* getting a terminal count interrupt is it not?
* If you get this BUG() the most probable cause is that
* the individual nodes in the lli chain have IRQ enabled,
* so check your platform config for lli chain ctrl.
*/
BUG_ON(list_empty(&cohc->active));
cohc->nbr_active_done++;
/*
* This attempt to take a job from cohc->queue, put it
* into cohc->active and start it.
*/
if (coh901318_queue_start(cohc) == NULL)
cohc->busy = 0;
spin_unlock(&cohc->lock);
/*
* This tasklet will remove items from cohc->active
* and thus terminates them.
*/
if (cohc_chan_conf(cohc)->priority_high)
tasklet_hi_schedule(&cohc->tasklet);
else
tasklet_schedule(&cohc->tasklet);
}
static irqreturn_t dma_irq_handler(int irq, void *dev_id)
{
u32 status1;
u32 status2;
int i;
int ch;
struct coh901318_base *base = dev_id;
struct coh901318_chan *cohc;
void __iomem *virtbase = base->virtbase;
status1 = readl(virtbase + COH901318_INT_STATUS1);
status2 = readl(virtbase + COH901318_INT_STATUS2);
if (unlikely(status1 == 0 && status2 == 0)) {
dev_warn(base->dev, "spurious DMA IRQ from no channel!\n");
return IRQ_HANDLED;
}
/* TODO: consider handle IRQ in tasklet here to
* minimize interrupt latency */
/* Check the first 32 DMA channels for IRQ */
while (status1) {
/* Find first bit set, return as a number. */
i = ffs(status1) - 1;
ch = i;
cohc = &base->chans[ch];
spin_lock(&cohc->lock);
/* Mask off this bit */
status1 &= ~(1 << i);
/* Check the individual channel bits */
if (test_bit(i, virtbase + COH901318_BE_INT_STATUS1)) {
dev_crit(COHC_2_DEV(cohc),
"DMA bus error on channel %d!\n", ch);
BUG_ON(1);
/* Clear BE interrupt */
__set_bit(i, virtbase + COH901318_BE_INT_CLEAR1);
} else {
/* Caused by TC, really? */
if (unlikely(!test_bit(i, virtbase +
COH901318_TC_INT_STATUS1))) {
dev_warn(COHC_2_DEV(cohc),
"ignoring interrupt not caused by terminal count on channel %d\n", ch);
/* Clear TC interrupt */
BUG_ON(1);
__set_bit(i, virtbase + COH901318_TC_INT_CLEAR1);
} else {
/* Enable powersave if transfer has finished */
if (!(readl(virtbase + COH901318_CX_STAT +
COH901318_CX_STAT_SPACING*ch) &
COH901318_CX_STAT_ENABLED)) {
enable_powersave(cohc);
}
/* Must clear TC interrupt before calling
* dma_tc_handle
* in case tc_handle initate a new dma job
*/
__set_bit(i, virtbase + COH901318_TC_INT_CLEAR1);
dma_tc_handle(cohc);
}
}
spin_unlock(&cohc->lock);
}
/* Check the remaining 32 DMA channels for IRQ */
while (status2) {
/* Find first bit set, return as a number. */
i = ffs(status2) - 1;
ch = i + 32;
cohc = &base->chans[ch];
spin_lock(&cohc->lock);
/* Mask off this bit */
status2 &= ~(1 << i);
/* Check the individual channel bits */
if (test_bit(i, virtbase + COH901318_BE_INT_STATUS2)) {
dev_crit(COHC_2_DEV(cohc),
"DMA bus error on channel %d!\n", ch);
/* Clear BE interrupt */
BUG_ON(1);
__set_bit(i, virtbase + COH901318_BE_INT_CLEAR2);
} else {
/* Caused by TC, really? */
if (unlikely(!test_bit(i, virtbase +
COH901318_TC_INT_STATUS2))) {
dev_warn(COHC_2_DEV(cohc),
"ignoring interrupt not caused by terminal count on channel %d\n", ch);
/* Clear TC interrupt */
__set_bit(i, virtbase + COH901318_TC_INT_CLEAR2);
BUG_ON(1);
} else {
/* Enable powersave if transfer has finished */
if (!(readl(virtbase + COH901318_CX_STAT +
COH901318_CX_STAT_SPACING*ch) &
COH901318_CX_STAT_ENABLED)) {
enable_powersave(cohc);
}
/* Must clear TC interrupt before calling
* dma_tc_handle
* in case tc_handle initate a new dma job
*/
__set_bit(i, virtbase + COH901318_TC_INT_CLEAR2);
dma_tc_handle(cohc);
}
}
spin_unlock(&cohc->lock);
}
return IRQ_HANDLED;
}
static int coh901318_alloc_chan_resources(struct dma_chan *chan)
{
struct coh901318_chan *cohc = to_coh901318_chan(chan);
unsigned long flags;
dev_vdbg(COHC_2_DEV(cohc), "[%s] DMA channel %d\n",
__func__, cohc->id);
if (chan->client_count > 1)
return -EBUSY;
spin_lock_irqsave(&cohc->lock, flags);
coh901318_config(cohc, NULL);
cohc->allocated = 1;
cohc->completed = chan->cookie = 1;
spin_unlock_irqrestore(&cohc->lock, flags);
return 1;
}
static void
coh901318_free_chan_resources(struct dma_chan *chan)
{
struct coh901318_chan *cohc = to_coh901318_chan(chan);
int channel = cohc->id;
unsigned long flags;
spin_lock_irqsave(&cohc->lock, flags);
/* Disable HW */
writel(0x00000000U, cohc->base->virtbase + COH901318_CX_CFG +
COH901318_CX_CFG_SPACING*channel);
writel(0x00000000U, cohc->base->virtbase + COH901318_CX_CTRL +
COH901318_CX_CTRL_SPACING*channel);
cohc->allocated = 0;
spin_unlock_irqrestore(&cohc->lock, flags);
chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
}
static dma_cookie_t
coh901318_tx_submit(struct dma_async_tx_descriptor *tx)
{
struct coh901318_desc *cohd = container_of(tx, struct coh901318_desc,
desc);
struct coh901318_chan *cohc = to_coh901318_chan(tx->chan);
unsigned long flags;
spin_lock_irqsave(&cohc->lock, flags);
tx->cookie = coh901318_assign_cookie(cohc, cohd);
coh901318_desc_queue(cohc, cohd);
spin_unlock_irqrestore(&cohc->lock, flags);
return tx->cookie;
}
static struct dma_async_tx_descriptor *
coh901318_prep_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
size_t size, unsigned long flags)
{
struct coh901318_lli *lli;
struct coh901318_desc *cohd;
unsigned long flg;
struct coh901318_chan *cohc = to_coh901318_chan(chan);
int lli_len;
u32 ctrl_last = cohc_chan_param(cohc)->ctrl_lli_last;
int ret;
spin_lock_irqsave(&cohc->lock, flg);
dev_vdbg(COHC_2_DEV(cohc),
"[%s] channel %d src 0x%x dest 0x%x size %d\n",
__func__, cohc->id, src, dest, size);
if (flags & DMA_PREP_INTERRUPT)
/* Trigger interrupt after last lli */
ctrl_last |= COH901318_CX_CTRL_TC_IRQ_ENABLE;
lli_len = size >> MAX_DMA_PACKET_SIZE_SHIFT;
if ((lli_len << MAX_DMA_PACKET_SIZE_SHIFT) < size)
lli_len++;
lli = coh901318_lli_alloc(&cohc->base->pool, lli_len);
if (lli == NULL)
goto err;
ret = coh901318_lli_fill_memcpy(
&cohc->base->pool, lli, src, size, dest,
cohc_chan_param(cohc)->ctrl_lli_chained,
ctrl_last);
if (ret)
goto err;
COH_DBG(coh901318_list_print(cohc, lli));
/* Pick a descriptor to handle this transfer */
cohd = coh901318_desc_get(cohc);
cohd->lli = lli;
cohd->flags = flags;
cohd->desc.tx_submit = coh901318_tx_submit;
spin_unlock_irqrestore(&cohc->lock, flg);
return &cohd->desc;
err:
spin_unlock_irqrestore(&cohc->lock, flg);
return NULL;
}
static struct dma_async_tx_descriptor *
coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
unsigned int sg_len, enum dma_data_direction direction,
unsigned long flags)
{
struct coh901318_chan *cohc = to_coh901318_chan(chan);
struct coh901318_lli *lli;
struct coh901318_desc *cohd;
const struct coh901318_params *params;
struct scatterlist *sg;
int len = 0;
int size;
int i;
u32 ctrl_chained = cohc_chan_param(cohc)->ctrl_lli_chained;
u32 ctrl = cohc_chan_param(cohc)->ctrl_lli;
u32 ctrl_last = cohc_chan_param(cohc)->ctrl_lli_last;
u32 config;
unsigned long flg;
int ret;
if (!sgl)
goto out;
if (sgl->length == 0)
goto out;
spin_lock_irqsave(&cohc->lock, flg);
dev_vdbg(COHC_2_DEV(cohc), "[%s] sg_len %d dir %d\n",
__func__, sg_len, direction);
if (flags & DMA_PREP_INTERRUPT)
/* Trigger interrupt after last lli */
ctrl_last |= COH901318_CX_CTRL_TC_IRQ_ENABLE;
params = cohc_chan_param(cohc);
config = params->config;
if (direction == DMA_TO_DEVICE) {
u32 tx_flags = COH901318_CX_CTRL_PRDD_SOURCE |
COH901318_CX_CTRL_SRC_ADDR_INC_ENABLE;
config |= COH901318_CX_CFG_RM_MEMORY_TO_PRIMARY;
ctrl_chained |= tx_flags;
ctrl_last |= tx_flags;
ctrl |= tx_flags;
} else if (direction == DMA_FROM_DEVICE) {
u32 rx_flags = COH901318_CX_CTRL_PRDD_DEST |
COH901318_CX_CTRL_DST_ADDR_INC_ENABLE;
config |= COH901318_CX_CFG_RM_PRIMARY_TO_MEMORY;
ctrl_chained |= rx_flags;
ctrl_last |= rx_flags;
ctrl |= rx_flags;
} else
goto err_direction;
coh901318_set_conf(cohc, config);
/* The dma only supports transmitting packages up to
* MAX_DMA_PACKET_SIZE. Calculate to total number of
* dma elemts required to send the entire sg list
*/
for_each_sg(sgl, sg, sg_len, i) {
unsigned int factor;
size = sg_dma_len(sg);
if (size <= MAX_DMA_PACKET_SIZE) {
len++;
continue;
}
factor = size >> MAX_DMA_PACKET_SIZE_SHIFT;
if ((factor << MAX_DMA_PACKET_SIZE_SHIFT) < size)
factor++;
len += factor;
}
pr_debug("Allocate %d lli:s for this transfer\n", len);
lli = coh901318_lli_alloc(&cohc->base->pool, len);
if (lli == NULL)
goto err_dma_alloc;
/* initiate allocated lli list */
ret = coh901318_lli_fill_sg(&cohc->base->pool, lli, sgl, sg_len,
cohc_dev_addr(cohc),
ctrl_chained,
ctrl,
ctrl_last,
direction, COH901318_CX_CTRL_TC_IRQ_ENABLE);
if (ret)
goto err_lli_fill;
COH_DBG(coh901318_list_print(cohc, lli));
/* Pick a descriptor to handle this transfer */
cohd = coh901318_desc_get(cohc);
cohd->dir = direction;
cohd->flags = flags;
cohd->desc.tx_submit = coh901318_tx_submit;
cohd->lli = lli;
spin_unlock_irqrestore(&cohc->lock, flg);
return &cohd->desc;
err_lli_fill:
err_dma_alloc:
err_direction:
spin_unlock_irqrestore(&cohc->lock, flg);
out:
return NULL;
}
static enum dma_status
coh901318_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
struct dma_tx_state *txstate)
{
struct coh901318_chan *cohc = to_coh901318_chan(chan);
dma_cookie_t last_used;
dma_cookie_t last_complete;
int ret;
last_complete = cohc->completed;
last_used = chan->cookie;
ret = dma_async_is_complete(cookie, last_complete, last_used);
dma_set_tx_state(txstate, last_complete, last_used,
coh901318_get_bytes_left(chan));
if (ret == DMA_IN_PROGRESS && cohc->stopped)
ret = DMA_PAUSED;
return ret;
}
static void
coh901318_issue_pending(struct dma_chan *chan)
{
struct coh901318_chan *cohc = to_coh901318_chan(chan);
unsigned long flags;
spin_lock_irqsave(&cohc->lock, flags);
/*
* Busy means that pending jobs are already being processed,
* and then there is no point in starting the queue: the
* terminal count interrupt on the channel will take the next
* job on the queue and execute it anyway.
*/
if (!cohc->busy)
coh901318_queue_start(cohc);
spin_unlock_irqrestore(&cohc->lock, flags);
}
static int
coh901318_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
unsigned long arg)
{
unsigned long flags;
struct coh901318_chan *cohc = to_coh901318_chan(chan);
struct coh901318_desc *cohd;
void __iomem *virtbase = cohc->base->virtbase;
if (cmd == DMA_PAUSE) {
coh901318_pause(chan);
return 0;
}
if (cmd == DMA_RESUME) {
coh901318_resume(chan);
return 0;
}
if (cmd != DMA_TERMINATE_ALL)
return -ENXIO;
/* The remainder of this function terminates the transfer */
coh901318_pause(chan);
spin_lock_irqsave(&cohc->lock, flags);
/* Clear any pending BE or TC interrupt */
if (cohc->id < 32) {
writel(1 << cohc->id, virtbase + COH901318_BE_INT_CLEAR1);
writel(1 << cohc->id, virtbase + COH901318_TC_INT_CLEAR1);
} else {
writel(1 << (cohc->id - 32), virtbase +
COH901318_BE_INT_CLEAR2);
writel(1 << (cohc->id - 32), virtbase +
COH901318_TC_INT_CLEAR2);
}
enable_powersave(cohc);
while ((cohd = coh901318_first_active_get(cohc))) {
/* release the lli allocation*/
coh901318_lli_free(&cohc->base->pool, &cohd->lli);
/* return desc to free-list */
coh901318_desc_remove(cohd);
coh901318_desc_free(cohc, cohd);
}
while ((cohd = coh901318_first_queued(cohc))) {
/* release the lli allocation*/
coh901318_lli_free(&cohc->base->pool, &cohd->lli);
/* return desc to free-list */
coh901318_desc_remove(cohd);
coh901318_desc_free(cohc, cohd);
}
cohc->nbr_active_done = 0;
cohc->busy = 0;
spin_unlock_irqrestore(&cohc->lock, flags);
return 0;
}
void coh901318_base_init(struct dma_device *dma, const int *pick_chans,
struct coh901318_base *base)
{
int chans_i;
int i = 0;
struct coh901318_chan *cohc;
INIT_LIST_HEAD(&dma->channels);
for (chans_i = 0; pick_chans[chans_i] != -1; chans_i += 2) {
for (i = pick_chans[chans_i]; i <= pick_chans[chans_i+1]; i++) {
cohc = &base->chans[i];
cohc->base = base;
cohc->chan.device = dma;
cohc->id = i;
/* TODO: do we really need this lock if only one
* client is connected to each channel?
*/
spin_lock_init(&cohc->lock);
cohc->nbr_active_done = 0;
cohc->busy = 0;
INIT_LIST_HEAD(&cohc->free);
INIT_LIST_HEAD(&cohc->active);
INIT_LIST_HEAD(&cohc->queue);
tasklet_init(&cohc->tasklet, dma_tasklet,
(unsigned long) cohc);
list_add_tail(&cohc->chan.device_node,
&dma->channels);
}
}
}
static int __init coh901318_probe(struct platform_device *pdev)
{
int err = 0;
struct coh901318_platform *pdata;
struct coh901318_base *base;
int irq;
struct resource *io;
io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!io)
goto err_get_resource;
/* Map DMA controller registers to virtual memory */
if (request_mem_region(io->start,
resource_size(io),
pdev->dev.driver->name) == NULL) {
err = -EBUSY;
goto err_request_mem;
}
pdata = pdev->dev.platform_data;
if (!pdata)
goto err_no_platformdata;
base = kmalloc(ALIGN(sizeof(struct coh901318_base), 4) +
pdata->max_channels *
sizeof(struct coh901318_chan),
GFP_KERNEL);
if (!base)
goto err_alloc_coh_dma_channels;
base->chans = ((void *)base) + ALIGN(sizeof(struct coh901318_base), 4);
base->virtbase = ioremap(io->start, resource_size(io));
if (!base->virtbase) {
err = -ENOMEM;
goto err_no_ioremap;
}
base->dev = &pdev->dev;
base->platform = pdata;
spin_lock_init(&base->pm.lock);
base->pm.started_channels = 0;
COH901318_DEBUGFS_ASSIGN(debugfs_dma_base, base);
platform_set_drvdata(pdev, base);
irq = platform_get_irq(pdev, 0);
if (irq < 0)
goto err_no_irq;
err = request_irq(irq, dma_irq_handler, IRQF_DISABLED,
"coh901318", base);
if (err) {
dev_crit(&pdev->dev,
"Cannot allocate IRQ for DMA controller!\n");
goto err_request_irq;
}
err = coh901318_pool_create(&base->pool, &pdev->dev,
sizeof(struct coh901318_lli),
32);
if (err)
goto err_pool_create;
/* init channels for device transfers */
coh901318_base_init(&base->dma_slave, base->platform->chans_slave,
base);
dma_cap_zero(base->dma_slave.cap_mask);
dma_cap_set(DMA_SLAVE, base->dma_slave.cap_mask);
base->dma_slave.device_alloc_chan_resources = coh901318_alloc_chan_resources;
base->dma_slave.device_free_chan_resources = coh901318_free_chan_resources;
base->dma_slave.device_prep_slave_sg = coh901318_prep_slave_sg;
base->dma_slave.device_tx_status = coh901318_tx_status;
base->dma_slave.device_issue_pending = coh901318_issue_pending;
base->dma_slave.device_control = coh901318_control;
base->dma_slave.dev = &pdev->dev;
err = dma_async_device_register(&base->dma_slave);
if (err)
goto err_register_slave;
/* init channels for memcpy */
coh901318_base_init(&base->dma_memcpy, base->platform->chans_memcpy,
base);
dma_cap_zero(base->dma_memcpy.cap_mask);
dma_cap_set(DMA_MEMCPY, base->dma_memcpy.cap_mask);
base->dma_memcpy.device_alloc_chan_resources = coh901318_alloc_chan_resources;
base->dma_memcpy.device_free_chan_resources = coh901318_free_chan_resources;
base->dma_memcpy.device_prep_dma_memcpy = coh901318_prep_memcpy;
base->dma_memcpy.device_tx_status = coh901318_tx_status;
base->dma_memcpy.device_issue_pending = coh901318_issue_pending;
base->dma_memcpy.device_control = coh901318_control;
base->dma_memcpy.dev = &pdev->dev;
/*
* This controller can only access address at even 32bit boundaries,
* i.e. 2^2
*/
base->dma_memcpy.copy_align = 2;
err = dma_async_device_register(&base->dma_memcpy);
if (err)
goto err_register_memcpy;
dev_info(&pdev->dev, "Initialized COH901318 DMA on virtual base 0x%08x\n",
(u32) base->virtbase);
return err;
err_register_memcpy:
dma_async_device_unregister(&base->dma_slave);
err_register_slave:
coh901318_pool_destroy(&base->pool);
err_pool_create:
free_irq(platform_get_irq(pdev, 0), base);
err_request_irq:
err_no_irq:
iounmap(base->virtbase);
err_no_ioremap:
kfree(base);
err_alloc_coh_dma_channels:
err_no_platformdata:
release_mem_region(pdev->resource->start,
resource_size(pdev->resource));
err_request_mem:
err_get_resource:
return err;
}
static int __exit coh901318_remove(struct platform_device *pdev)
{
struct coh901318_base *base = platform_get_drvdata(pdev);
dma_async_device_unregister(&base->dma_memcpy);
dma_async_device_unregister(&base->dma_slave);
coh901318_pool_destroy(&base->pool);
free_irq(platform_get_irq(pdev, 0), base);
iounmap(base->virtbase);
kfree(base);
release_mem_region(pdev->resource->start,
resource_size(pdev->resource));
return 0;
}
static struct platform_driver coh901318_driver = {
.remove = __exit_p(coh901318_remove),
.driver = {
.name = "coh901318",
},
};
int __init coh901318_init(void)
{
return platform_driver_probe(&coh901318_driver, coh901318_probe);
}
subsys_initcall(coh901318_init);
void __exit coh901318_exit(void)
{
platform_driver_unregister(&coh901318_driver);
}
module_exit(coh901318_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Per Friden");