fsldma.c
/*
* Freescale MPC85xx, MPC83xx DMA Engine support
*
* Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
*
* Author:
* Zhang Wei <wei.zhang@freescale.com>, Jul 2007
* Ebony Zhu <ebony.zhu@freescale.com>, May 2007
*
* Description:
* DMA engine driver for Freescale MPC8540 DMA controller, which is
* also fit for MPC8560, MPC8555, MPC8548, MPC8641, and etc.
* The support for MPC8349 DMA contorller is also added.
*
* This 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.
*
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/dmaengine.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/dmapool.h>
#include <linux/of_platform.h>
#include "fsldma.h"
static void dma_init(struct fsl_dma_chan *fsl_chan)
{
/* Reset the channel */
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, 0, 32);
switch (fsl_chan->feature & FSL_DMA_IP_MASK) {
case FSL_DMA_IP_85XX:
/* Set the channel to below modes:
* EIE - Error interrupt enable
* EOSIE - End of segments interrupt enable (basic mode)
* EOLNIE - End of links interrupt enable
*/
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EIE
| FSL_DMA_MR_EOLNIE | FSL_DMA_MR_EOSIE, 32);
break;
case FSL_DMA_IP_83XX:
/* Set the channel to below modes:
* EOTIE - End-of-transfer interrupt enable
*/
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EOTIE,
32);
break;
}
}
static void set_sr(struct fsl_dma_chan *fsl_chan, u32 val)
{
DMA_OUT(fsl_chan, &fsl_chan->reg_base->sr, val, 32);
}
static u32 get_sr(struct fsl_dma_chan *fsl_chan)
{
return DMA_IN(fsl_chan, &fsl_chan->reg_base->sr, 32);
}
static void set_desc_cnt(struct fsl_dma_chan *fsl_chan,
struct fsl_dma_ld_hw *hw, u32 count)
{
hw->count = CPU_TO_DMA(fsl_chan, count, 32);
}
static void set_desc_src(struct fsl_dma_chan *fsl_chan,
struct fsl_dma_ld_hw *hw, dma_addr_t src)
{
u64 snoop_bits;
snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX)
? ((u64)FSL_DMA_SATR_SREADTYPE_SNOOP_READ << 32) : 0;
hw->src_addr = CPU_TO_DMA(fsl_chan, snoop_bits | src, 64);
}
static void set_desc_dest(struct fsl_dma_chan *fsl_chan,
struct fsl_dma_ld_hw *hw, dma_addr_t dest)
{
u64 snoop_bits;
snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX)
? ((u64)FSL_DMA_DATR_DWRITETYPE_SNOOP_WRITE << 32) : 0;
hw->dst_addr = CPU_TO_DMA(fsl_chan, snoop_bits | dest, 64);
}
static void set_desc_next(struct fsl_dma_chan *fsl_chan,
struct fsl_dma_ld_hw *hw, dma_addr_t next)
{
u64 snoop_bits;
snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX)
? FSL_DMA_SNEN : 0;
hw->next_ln_addr = CPU_TO_DMA(fsl_chan, snoop_bits | next, 64);
}
static void set_cdar(struct fsl_dma_chan *fsl_chan, dma_addr_t addr)
{
DMA_OUT(fsl_chan, &fsl_chan->reg_base->cdar, addr | FSL_DMA_SNEN, 64);
}
static dma_addr_t get_cdar(struct fsl_dma_chan *fsl_chan)
{
return DMA_IN(fsl_chan, &fsl_chan->reg_base->cdar, 64) & ~FSL_DMA_SNEN;
}
static void set_ndar(struct fsl_dma_chan *fsl_chan, dma_addr_t addr)
{
DMA_OUT(fsl_chan, &fsl_chan->reg_base->ndar, addr, 64);
}
static dma_addr_t get_ndar(struct fsl_dma_chan *fsl_chan)
{
return DMA_IN(fsl_chan, &fsl_chan->reg_base->ndar, 64);
}
static u32 get_bcr(struct fsl_dma_chan *fsl_chan)
{
return DMA_IN(fsl_chan, &fsl_chan->reg_base->bcr, 32);
}
static int dma_is_idle(struct fsl_dma_chan *fsl_chan)
{
u32 sr = get_sr(fsl_chan);
return (!(sr & FSL_DMA_SR_CB)) || (sr & FSL_DMA_SR_CH);
}
static void dma_start(struct fsl_dma_chan *fsl_chan)
{
u32 mr_set = 0;;
if (fsl_chan->feature & FSL_DMA_CHAN_PAUSE_EXT) {
DMA_OUT(fsl_chan, &fsl_chan->reg_base->bcr, 0, 32);
mr_set |= FSL_DMA_MR_EMP_EN;
} else
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
& ~FSL_DMA_MR_EMP_EN, 32);
if (fsl_chan->feature & FSL_DMA_CHAN_START_EXT)
mr_set |= FSL_DMA_MR_EMS_EN;
else
mr_set |= FSL_DMA_MR_CS;
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
| mr_set, 32);
}
static void dma_halt(struct fsl_dma_chan *fsl_chan)
{
int i;
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) | FSL_DMA_MR_CA,
32);
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) & ~(FSL_DMA_MR_CS
| FSL_DMA_MR_EMS_EN | FSL_DMA_MR_CA), 32);
for (i = 0; i < 100; i++) {
if (dma_is_idle(fsl_chan))
break;
udelay(10);
}
if (i >= 100 && !dma_is_idle(fsl_chan))
dev_err(fsl_chan->dev, "DMA halt timeout!\n");
}
static void set_ld_eol(struct fsl_dma_chan *fsl_chan,
struct fsl_desc_sw *desc)
{
desc->hw.next_ln_addr = CPU_TO_DMA(fsl_chan,
DMA_TO_CPU(fsl_chan, desc->hw.next_ln_addr, 64) | FSL_DMA_EOL,
64);
}
static void append_ld_queue(struct fsl_dma_chan *fsl_chan,
struct fsl_desc_sw *new_desc)
{
struct fsl_desc_sw *queue_tail = to_fsl_desc(fsl_chan->ld_queue.prev);
if (list_empty(&fsl_chan->ld_queue))
return;
/* Link to the new descriptor physical address and
* Enable End-of-segment interrupt for
* the last link descriptor.
* (the previous node's next link descriptor)
*
* For FSL_DMA_IP_83xx, the snoop enable bit need be set.
*/
queue_tail->hw.next_ln_addr = CPU_TO_DMA(fsl_chan,
new_desc->async_tx.phys | FSL_DMA_EOSIE |
(((fsl_chan->feature & FSL_DMA_IP_MASK)
== FSL_DMA_IP_83XX) ? FSL_DMA_SNEN : 0), 64);
}
/**
* fsl_chan_set_src_loop_size - Set source address hold transfer size
* @fsl_chan : Freescale DMA channel
* @size : Address loop size, 0 for disable loop
*
* The set source address hold transfer size. The source
* address hold or loop transfer size is when the DMA transfer
* data from source address (SA), if the loop size is 4, the DMA will
* read data from SA, SA + 1, SA + 2, SA + 3, then loop back to SA,
* SA + 1 ... and so on.
*/
static void fsl_chan_set_src_loop_size(struct fsl_dma_chan *fsl_chan, int size)
{
switch (size) {
case 0:
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) &
(~FSL_DMA_MR_SAHE), 32);
break;
case 1:
case 2:
case 4:
case 8:
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) |
FSL_DMA_MR_SAHE | (__ilog2(size) << 14),
32);
break;
}
}
/**
* fsl_chan_set_dest_loop_size - Set destination address hold transfer size
* @fsl_chan : Freescale DMA channel
* @size : Address loop size, 0 for disable loop
*
* The set destination address hold transfer size. The destination
* address hold or loop transfer size is when the DMA transfer
* data to destination address (TA), if the loop size is 4, the DMA will
* write data to TA, TA + 1, TA + 2, TA + 3, then loop back to TA,
* TA + 1 ... and so on.
*/
static void fsl_chan_set_dest_loop_size(struct fsl_dma_chan *fsl_chan, int size)
{
switch (size) {
case 0:
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) &
(~FSL_DMA_MR_DAHE), 32);
break;
case 1:
case 2:
case 4:
case 8:
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) |
FSL_DMA_MR_DAHE | (__ilog2(size) << 16),
32);
break;
}
}
/**
* fsl_chan_toggle_ext_pause - Toggle channel external pause status
* @fsl_chan : Freescale DMA channel
* @size : Pause control size, 0 for disable external pause control.
* The maximum is 1024.
*
* The Freescale DMA channel can be controlled by the external
* signal DREQ#. The pause control size is how many bytes are allowed
* to transfer before pausing the channel, after which a new assertion
* of DREQ# resumes channel operation.
*/
static void fsl_chan_toggle_ext_pause(struct fsl_dma_chan *fsl_chan, int size)
{
if (size > 1024)
return;
if (size) {
DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
| ((__ilog2(size) << 24) & 0x0f000000),
32);
fsl_chan->feature |= FSL_DMA_CHAN_PAUSE_EXT;
} else
fsl_chan->feature &= ~FSL_DMA_CHAN_PAUSE_EXT;
}
/**
* fsl_chan_toggle_ext_start - Toggle channel external start status
* @fsl_chan : Freescale DMA channel
* @enable : 0 is disabled, 1 is enabled.
*
* If enable the external start, the channel can be started by an
* external DMA start pin. So the dma_start() does not start the
* transfer immediately. The DMA channel will wait for the
* control pin asserted.
*/
static void fsl_chan_toggle_ext_start(struct fsl_dma_chan *fsl_chan, int enable)
{
if (enable)
fsl_chan->feature |= FSL_DMA_CHAN_START_EXT;
else
fsl_chan->feature &= ~FSL_DMA_CHAN_START_EXT;
}
static dma_cookie_t fsl_dma_tx_submit(struct dma_async_tx_descriptor *tx)
{
struct fsl_desc_sw *desc = tx_to_fsl_desc(tx);
struct fsl_dma_chan *fsl_chan = to_fsl_chan(tx->chan);
unsigned long flags;
dma_cookie_t cookie;
/* cookie increment and adding to ld_queue must be atomic */
spin_lock_irqsave(&fsl_chan->desc_lock, flags);
cookie = fsl_chan->common.cookie;
cookie++;
if (cookie < 0)
cookie = 1;
desc->async_tx.cookie = cookie;
fsl_chan->common.cookie = desc->async_tx.cookie;
append_ld_queue(fsl_chan, desc);
list_splice_init(&desc->async_tx.tx_list, fsl_chan->ld_queue.prev);
spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
return cookie;
}
/**
* fsl_dma_alloc_descriptor - Allocate descriptor from channel's DMA pool.
* @fsl_chan : Freescale DMA channel
*
* Return - The descriptor allocated. NULL for failed.
*/
static struct fsl_desc_sw *fsl_dma_alloc_descriptor(
struct fsl_dma_chan *fsl_chan)
{
dma_addr_t pdesc;
struct fsl_desc_sw *desc_sw;
desc_sw = dma_pool_alloc(fsl_chan->desc_pool, GFP_ATOMIC, &pdesc);
if (desc_sw) {
memset(desc_sw, 0, sizeof(struct fsl_desc_sw));
dma_async_tx_descriptor_init(&desc_sw->async_tx,
&fsl_chan->common);
desc_sw->async_tx.tx_submit = fsl_dma_tx_submit;
INIT_LIST_HEAD(&desc_sw->async_tx.tx_list);
desc_sw->async_tx.phys = pdesc;
}
return desc_sw;
}
/**
* fsl_dma_alloc_chan_resources - Allocate resources for DMA channel.
* @fsl_chan : Freescale DMA channel
*
* This function will create a dma pool for descriptor allocation.
*
* Return - The number of descriptors allocated.
*/
static int fsl_dma_alloc_chan_resources(struct dma_chan *chan)
{
struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
/* Has this channel already been allocated? */
if (fsl_chan->desc_pool)
return 1;
/* We need the descriptor to be aligned to 32bytes
* for meeting FSL DMA specification requirement.
*/
fsl_chan->desc_pool = dma_pool_create("fsl_dma_engine_desc_pool",
fsl_chan->dev, sizeof(struct fsl_desc_sw),
32, 0);
if (!fsl_chan->desc_pool) {
dev_err(fsl_chan->dev, "No memory for channel %d "
"descriptor dma pool.\n", fsl_chan->id);
return 0;
}
return 1;
}
/**
* fsl_dma_free_chan_resources - Free all resources of the channel.
* @fsl_chan : Freescale DMA channel
*/
static void fsl_dma_free_chan_resources(struct dma_chan *chan)
{
struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
struct fsl_desc_sw *desc, *_desc;
unsigned long flags;
dev_dbg(fsl_chan->dev, "Free all channel resources.\n");
spin_lock_irqsave(&fsl_chan->desc_lock, flags);
list_for_each_entry_safe(desc, _desc, &fsl_chan->ld_queue, node) {
#ifdef FSL_DMA_LD_DEBUG
dev_dbg(fsl_chan->dev,
"LD %p will be released.\n", desc);
#endif
list_del(&desc->node);
/* free link descriptor */
dma_pool_free(fsl_chan->desc_pool, desc, desc->async_tx.phys);
}
spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
dma_pool_destroy(fsl_chan->desc_pool);
fsl_chan->desc_pool = NULL;
}
static struct dma_async_tx_descriptor *
fsl_dma_prep_interrupt(struct dma_chan *chan, unsigned long flags)
{
struct fsl_dma_chan *fsl_chan;
struct fsl_desc_sw *new;
if (!chan)
return NULL;
fsl_chan = to_fsl_chan(chan);
new = fsl_dma_alloc_descriptor(fsl_chan);
if (!new) {
dev_err(fsl_chan->dev, "No free memory for link descriptor\n");
return NULL;
}
new->async_tx.cookie = -EBUSY;
new->async_tx.flags = flags;
/* Insert the link descriptor to the LD ring */
list_add_tail(&new->node, &new->async_tx.tx_list);
/* Set End-of-link to the last link descriptor of new list*/
set_ld_eol(fsl_chan, new);
return &new->async_tx;
}
static struct dma_async_tx_descriptor *fsl_dma_prep_memcpy(
struct dma_chan *chan, dma_addr_t dma_dest, dma_addr_t dma_src,
size_t len, unsigned long flags)
{
struct fsl_dma_chan *fsl_chan;
struct fsl_desc_sw *first = NULL, *prev = NULL, *new;
size_t copy;
LIST_HEAD(link_chain);
if (!chan)
return NULL;
if (!len)
return NULL;
fsl_chan = to_fsl_chan(chan);
do {
/* Allocate the link descriptor from DMA pool */
new = fsl_dma_alloc_descriptor(fsl_chan);
if (!new) {
dev_err(fsl_chan->dev,
"No free memory for link descriptor\n");
return NULL;
}
#ifdef FSL_DMA_LD_DEBUG
dev_dbg(fsl_chan->dev, "new link desc alloc %p\n", new);
#endif
copy = min(len, (size_t)FSL_DMA_BCR_MAX_CNT);
set_desc_cnt(fsl_chan, &new->hw, copy);
set_desc_src(fsl_chan, &new->hw, dma_src);
set_desc_dest(fsl_chan, &new->hw, dma_dest);
if (!first)
first = new;
else
set_desc_next(fsl_chan, &prev->hw, new->async_tx.phys);
new->async_tx.cookie = 0;
async_tx_ack(&new->async_tx);
prev = new;
len -= copy;
dma_src += copy;
dma_dest += copy;
/* Insert the link descriptor to the LD ring */
list_add_tail(&new->node, &first->async_tx.tx_list);
} while (len);
new->async_tx.flags = flags; /* client is in control of this ack */
new->async_tx.cookie = -EBUSY;
/* Set End-of-link to the last link descriptor of new list*/
set_ld_eol(fsl_chan, new);
return first ? &first->async_tx : NULL;
}
/**
* fsl_dma_update_completed_cookie - Update the completed cookie.
* @fsl_chan : Freescale DMA channel
*/
static void fsl_dma_update_completed_cookie(struct fsl_dma_chan *fsl_chan)
{
struct fsl_desc_sw *cur_desc, *desc;
dma_addr_t ld_phy;
ld_phy = get_cdar(fsl_chan) & FSL_DMA_NLDA_MASK;
if (ld_phy) {
cur_desc = NULL;
list_for_each_entry(desc, &fsl_chan->ld_queue, node)
if (desc->async_tx.phys == ld_phy) {
cur_desc = desc;
break;
}
if (cur_desc && cur_desc->async_tx.cookie) {
if (dma_is_idle(fsl_chan))
fsl_chan->completed_cookie =
cur_desc->async_tx.cookie;
else
fsl_chan->completed_cookie =
cur_desc->async_tx.cookie - 1;
}
}
}
/**
* fsl_chan_ld_cleanup - Clean up link descriptors
* @fsl_chan : Freescale DMA channel
*
* This function clean up the ld_queue of DMA channel.
* If 'in_intr' is set, the function will move the link descriptor to
* the recycle list. Otherwise, free it directly.
*/
static void fsl_chan_ld_cleanup(struct fsl_dma_chan *fsl_chan)
{
struct fsl_desc_sw *desc, *_desc;
unsigned long flags;
spin_lock_irqsave(&fsl_chan->desc_lock, flags);
dev_dbg(fsl_chan->dev, "chan completed_cookie = %d\n",
fsl_chan->completed_cookie);
list_for_each_entry_safe(desc, _desc, &fsl_chan->ld_queue, node) {
dma_async_tx_callback callback;
void *callback_param;
if (dma_async_is_complete(desc->async_tx.cookie,
fsl_chan->completed_cookie, fsl_chan->common.cookie)
== DMA_IN_PROGRESS)
break;
callback = desc->async_tx.callback;
callback_param = desc->async_tx.callback_param;
/* Remove from ld_queue list */
list_del(&desc->node);
dev_dbg(fsl_chan->dev, "link descriptor %p will be recycle.\n",
desc);
dma_pool_free(fsl_chan->desc_pool, desc, desc->async_tx.phys);
/* Run the link descriptor callback function */
if (callback) {
spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
dev_dbg(fsl_chan->dev, "link descriptor %p callback\n",
desc);
callback(callback_param);
spin_lock_irqsave(&fsl_chan->desc_lock, flags);
}
}
spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
}
/**
* fsl_chan_xfer_ld_queue - Transfer link descriptors in channel ld_queue.
* @fsl_chan : Freescale DMA channel
*/
static void fsl_chan_xfer_ld_queue(struct fsl_dma_chan *fsl_chan)
{
struct list_head *ld_node;
dma_addr_t next_dest_addr;
unsigned long flags;
if (!dma_is_idle(fsl_chan))
return;
dma_halt(fsl_chan);
/* If there are some link descriptors
* not transfered in queue. We need to start it.
*/
spin_lock_irqsave(&fsl_chan->desc_lock, flags);
/* Find the first un-transfer desciptor */
for (ld_node = fsl_chan->ld_queue.next;
(ld_node != &fsl_chan->ld_queue)
&& (dma_async_is_complete(
to_fsl_desc(ld_node)->async_tx.cookie,
fsl_chan->completed_cookie,
fsl_chan->common.cookie) == DMA_SUCCESS);
ld_node = ld_node->next);
spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
if (ld_node != &fsl_chan->ld_queue) {
/* Get the ld start address from ld_queue */
next_dest_addr = to_fsl_desc(ld_node)->async_tx.phys;
dev_dbg(fsl_chan->dev, "xfer LDs staring from %p\n",
(void *)next_dest_addr);
set_cdar(fsl_chan, next_dest_addr);
dma_start(fsl_chan);
} else {
set_cdar(fsl_chan, 0);
set_ndar(fsl_chan, 0);
}
}
/**
* fsl_dma_memcpy_issue_pending - Issue the DMA start command
* @fsl_chan : Freescale DMA channel
*/
static void fsl_dma_memcpy_issue_pending(struct dma_chan *chan)
{
struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
#ifdef FSL_DMA_LD_DEBUG
struct fsl_desc_sw *ld;
unsigned long flags;
spin_lock_irqsave(&fsl_chan->desc_lock, flags);
if (list_empty(&fsl_chan->ld_queue)) {
spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
return;
}
dev_dbg(fsl_chan->dev, "--memcpy issue--\n");
list_for_each_entry(ld, &fsl_chan->ld_queue, node) {
int i;
dev_dbg(fsl_chan->dev, "Ch %d, LD %08x\n",
fsl_chan->id, ld->async_tx.phys);
for (i = 0; i < 8; i++)
dev_dbg(fsl_chan->dev, "LD offset %d: %08x\n",
i, *(((u32 *)&ld->hw) + i));
}
dev_dbg(fsl_chan->dev, "----------------\n");
spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
#endif
fsl_chan_xfer_ld_queue(fsl_chan);
}
/**
* fsl_dma_is_complete - Determine the DMA status
* @fsl_chan : Freescale DMA channel
*/
static enum dma_status fsl_dma_is_complete(struct dma_chan *chan,
dma_cookie_t cookie,
dma_cookie_t *done,
dma_cookie_t *used)
{
struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
dma_cookie_t last_used;
dma_cookie_t last_complete;
fsl_chan_ld_cleanup(fsl_chan);
last_used = chan->cookie;
last_complete = fsl_chan->completed_cookie;
if (done)
*done = last_complete;
if (used)
*used = last_used;
return dma_async_is_complete(cookie, last_complete, last_used);
}
static irqreturn_t fsl_dma_chan_do_interrupt(int irq, void *data)
{
struct fsl_dma_chan *fsl_chan = (struct fsl_dma_chan *)data;
u32 stat;
int update_cookie = 0;
int xfer_ld_q = 0;
stat = get_sr(fsl_chan);
dev_dbg(fsl_chan->dev, "event: channel %d, stat = 0x%x\n",
fsl_chan->id, stat);
set_sr(fsl_chan, stat); /* Clear the event register */
stat &= ~(FSL_DMA_SR_CB | FSL_DMA_SR_CH);
if (!stat)
return IRQ_NONE;
if (stat & FSL_DMA_SR_TE)
dev_err(fsl_chan->dev, "Transfer Error!\n");
/* Programming Error
* The DMA_INTERRUPT async_tx is a NULL transfer, which will
* triger a PE interrupt.
*/
if (stat & FSL_DMA_SR_PE) {
dev_dbg(fsl_chan->dev, "event: Programming Error INT\n");
if (get_bcr(fsl_chan) == 0) {
/* BCR register is 0, this is a DMA_INTERRUPT async_tx.
* Now, update the completed cookie, and continue the
* next uncompleted transfer.
*/
update_cookie = 1;
xfer_ld_q = 1;
}
stat &= ~FSL_DMA_SR_PE;
}
/* If the link descriptor segment transfer finishes,
* we will recycle the used descriptor.
*/
if (stat & FSL_DMA_SR_EOSI) {
dev_dbg(fsl_chan->dev, "event: End-of-segments INT\n");
dev_dbg(fsl_chan->dev, "event: clndar %p, nlndar %p\n",
(void *)get_cdar(fsl_chan), (void *)get_ndar(fsl_chan));
stat &= ~FSL_DMA_SR_EOSI;
update_cookie = 1;
}
/* For MPC8349, EOCDI event need to update cookie
* and start the next transfer if it exist.
*/
if (stat & FSL_DMA_SR_EOCDI) {
dev_dbg(fsl_chan->dev, "event: End-of-Chain link INT\n");
stat &= ~FSL_DMA_SR_EOCDI;
update_cookie = 1;
xfer_ld_q = 1;
}
/* If it current transfer is the end-of-transfer,
* we should clear the Channel Start bit for
* prepare next transfer.
*/
if (stat & FSL_DMA_SR_EOLNI) {
dev_dbg(fsl_chan->dev, "event: End-of-link INT\n");
stat &= ~FSL_DMA_SR_EOLNI;
xfer_ld_q = 1;
}
if (update_cookie)
fsl_dma_update_completed_cookie(fsl_chan);
if (xfer_ld_q)
fsl_chan_xfer_ld_queue(fsl_chan);
if (stat)
dev_dbg(fsl_chan->dev, "event: unhandled sr 0x%02x\n",
stat);
dev_dbg(fsl_chan->dev, "event: Exit\n");
tasklet_schedule(&fsl_chan->tasklet);
return IRQ_HANDLED;
}
static irqreturn_t fsl_dma_do_interrupt(int irq, void *data)
{
struct fsl_dma_device *fdev = (struct fsl_dma_device *)data;
u32 gsr;
int ch_nr;
gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->reg_base)
: in_le32(fdev->reg_base);
ch_nr = (32 - ffs(gsr)) / 8;
return fdev->chan[ch_nr] ? fsl_dma_chan_do_interrupt(irq,
fdev->chan[ch_nr]) : IRQ_NONE;
}
static void dma_do_tasklet(unsigned long data)
{
struct fsl_dma_chan *fsl_chan = (struct fsl_dma_chan *)data;
fsl_chan_ld_cleanup(fsl_chan);
}
static int __devinit fsl_dma_chan_probe(struct fsl_dma_device *fdev,
struct device_node *node, u32 feature, const char *compatible)
{
struct fsl_dma_chan *new_fsl_chan;
int err;
/* alloc channel */
new_fsl_chan = kzalloc(sizeof(struct fsl_dma_chan), GFP_KERNEL);
if (!new_fsl_chan) {
dev_err(fdev->dev, "No free memory for allocating "
"dma channels!\n");
return -ENOMEM;
}
/* get dma channel register base */
err = of_address_to_resource(node, 0, &new_fsl_chan->reg);
if (err) {
dev_err(fdev->dev, "Can't get %s property 'reg'\n",
node->full_name);
goto err_no_reg;
}
new_fsl_chan->feature = feature;
if (!fdev->feature)
fdev->feature = new_fsl_chan->feature;
/* If the DMA device's feature is different than its channels',
* report the bug.
*/
WARN_ON(fdev->feature != new_fsl_chan->feature);
new_fsl_chan->dev = fdev->dev;
new_fsl_chan->reg_base = ioremap(new_fsl_chan->reg.start,
new_fsl_chan->reg.end - new_fsl_chan->reg.start + 1);
new_fsl_chan->id = ((new_fsl_chan->reg.start - 0x100) & 0xfff) >> 7;
if (new_fsl_chan->id > FSL_DMA_MAX_CHANS_PER_DEVICE) {
dev_err(fdev->dev, "There is no %d channel!\n",
new_fsl_chan->id);
err = -EINVAL;
goto err_no_chan;
}
fdev->chan[new_fsl_chan->id] = new_fsl_chan;
tasklet_init(&new_fsl_chan->tasklet, dma_do_tasklet,
(unsigned long)new_fsl_chan);
/* Init the channel */
dma_init(new_fsl_chan);
/* Clear cdar registers */
set_cdar(new_fsl_chan, 0);
switch (new_fsl_chan->feature & FSL_DMA_IP_MASK) {
case FSL_DMA_IP_85XX:
new_fsl_chan->toggle_ext_start = fsl_chan_toggle_ext_start;
new_fsl_chan->toggle_ext_pause = fsl_chan_toggle_ext_pause;
case FSL_DMA_IP_83XX:
new_fsl_chan->set_src_loop_size = fsl_chan_set_src_loop_size;
new_fsl_chan->set_dest_loop_size = fsl_chan_set_dest_loop_size;
}
spin_lock_init(&new_fsl_chan->desc_lock);
INIT_LIST_HEAD(&new_fsl_chan->ld_queue);
new_fsl_chan->common.device = &fdev->common;
/* Add the channel to DMA device channel list */
list_add_tail(&new_fsl_chan->common.device_node,
&fdev->common.channels);
fdev->common.chancnt++;
new_fsl_chan->irq = irq_of_parse_and_map(node, 0);
if (new_fsl_chan->irq != NO_IRQ) {
err = request_irq(new_fsl_chan->irq,
&fsl_dma_chan_do_interrupt, IRQF_SHARED,
"fsldma-channel", new_fsl_chan);
if (err) {
dev_err(fdev->dev, "DMA channel %s request_irq error "
"with return %d\n", node->full_name, err);
goto err_no_irq;
}
}
dev_info(fdev->dev, "#%d (%s), irq %d\n", new_fsl_chan->id,
compatible,
new_fsl_chan->irq != NO_IRQ ? new_fsl_chan->irq : fdev->irq);
return 0;
err_no_irq:
list_del(&new_fsl_chan->common.device_node);
err_no_chan:
iounmap(new_fsl_chan->reg_base);
err_no_reg:
kfree(new_fsl_chan);
return err;
}
static void fsl_dma_chan_remove(struct fsl_dma_chan *fchan)
{
if (fchan->irq != NO_IRQ)
free_irq(fchan->irq, fchan);
list_del(&fchan->common.device_node);
iounmap(fchan->reg_base);
kfree(fchan);
}
static int __devinit of_fsl_dma_probe(struct of_device *dev,
const struct of_device_id *match)
{
int err;
struct fsl_dma_device *fdev;
struct device_node *child;
fdev = kzalloc(sizeof(struct fsl_dma_device), GFP_KERNEL);
if (!fdev) {
dev_err(&dev->dev, "No enough memory for 'priv'\n");
return -ENOMEM;
}
fdev->dev = &dev->dev;
INIT_LIST_HEAD(&fdev->common.channels);
/* get DMA controller register base */
err = of_address_to_resource(dev->node, 0, &fdev->reg);
if (err) {
dev_err(&dev->dev, "Can't get %s property 'reg'\n",
dev->node->full_name);
goto err_no_reg;
}
dev_info(&dev->dev, "Probe the Freescale DMA driver for %s "
"controller at %p...\n",
match->compatible, (void *)fdev->reg.start);
fdev->reg_base = ioremap(fdev->reg.start, fdev->reg.end
- fdev->reg.start + 1);
dma_cap_set(DMA_MEMCPY, fdev->common.cap_mask);
dma_cap_set(DMA_INTERRUPT, fdev->common.cap_mask);
fdev->common.device_alloc_chan_resources = fsl_dma_alloc_chan_resources;
fdev->common.device_free_chan_resources = fsl_dma_free_chan_resources;
fdev->common.device_prep_dma_interrupt = fsl_dma_prep_interrupt;
fdev->common.device_prep_dma_memcpy = fsl_dma_prep_memcpy;
fdev->common.device_is_tx_complete = fsl_dma_is_complete;
fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending;
fdev->common.dev = &dev->dev;
fdev->irq = irq_of_parse_and_map(dev->node, 0);
if (fdev->irq != NO_IRQ) {
err = request_irq(fdev->irq, &fsl_dma_do_interrupt, IRQF_SHARED,
"fsldma-device", fdev);
if (err) {
dev_err(&dev->dev, "DMA device request_irq error "
"with return %d\n", err);
goto err;
}
}
dev_set_drvdata(&(dev->dev), fdev);
/* We cannot use of_platform_bus_probe() because there is no
* of_platform_bus_remove. Instead, we manually instantiate every DMA
* channel object.
*/
for_each_child_of_node(dev->node, child) {
if (of_device_is_compatible(child, "fsl,eloplus-dma-channel"))
fsl_dma_chan_probe(fdev, child,
FSL_DMA_IP_85XX | FSL_DMA_BIG_ENDIAN,
"fsl,eloplus-dma-channel");
if (of_device_is_compatible(child, "fsl,elo-dma-channel"))
fsl_dma_chan_probe(fdev, child,
FSL_DMA_IP_83XX | FSL_DMA_LITTLE_ENDIAN,
"fsl,elo-dma-channel");
}
dma_async_device_register(&fdev->common);
return 0;
err:
iounmap(fdev->reg_base);
err_no_reg:
kfree(fdev);
return err;
}
static int of_fsl_dma_remove(struct of_device *of_dev)
{
struct fsl_dma_device *fdev;
unsigned int i;
fdev = dev_get_drvdata(&of_dev->dev);
dma_async_device_unregister(&fdev->common);
for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++)
if (fdev->chan[i])
fsl_dma_chan_remove(fdev->chan[i]);
if (fdev->irq != NO_IRQ)
free_irq(fdev->irq, fdev);
iounmap(fdev->reg_base);
kfree(fdev);
dev_set_drvdata(&of_dev->dev, NULL);
return 0;
}
static struct of_device_id of_fsl_dma_ids[] = {
{ .compatible = "fsl,eloplus-dma", },
{ .compatible = "fsl,elo-dma", },
{}
};
static struct of_platform_driver of_fsl_dma_driver = {
.name = "fsl-elo-dma",
.match_table = of_fsl_dma_ids,
.probe = of_fsl_dma_probe,
.remove = of_fsl_dma_remove,
};
static __init int of_fsl_dma_init(void)
{
int ret;
pr_info("Freescale Elo / Elo Plus DMA driver\n");
ret = of_register_platform_driver(&of_fsl_dma_driver);
if (ret)
pr_err("fsldma: failed to register platform driver\n");
return ret;
}
static void __exit of_fsl_dma_exit(void)
{
of_unregister_platform_driver(&of_fsl_dma_driver);
}
subsys_initcall(of_fsl_dma_init);
module_exit(of_fsl_dma_exit);
MODULE_DESCRIPTION("Freescale Elo / Elo Plus DMA driver");
MODULE_LICENSE("GPL");