linux/drivers/dma/mxs-dma.c
Linus Torvalds 84a442b9a1 arm-soc: device tree conversions, part 2
These continue the device tree work from part 1, this set is for the
 tegra, mxs and imx platforms, all of which have dependencies on clock
 or pinctrl changes submitted earlier.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.11 (GNU/Linux)
 
 iQIcBAABAgAGBQJPuex7AAoJEIwa5zzehBx3xsQP/jkyt74MvuKUi8pi2zkeMIgn
 4XieyqcA0KZjJzfB22q3GIZjNIf/mEIGE4E/3bneVMPh/E2zaiohaXFExBmjNjml
 hhzWeZlFGPBjrZsfpIXJIIUhwSI7gX2rjYh4npJmdNhZmy8Y89XnpNJhN1kOwMuV
 oN23hPWoSVGbyDMQ0fmHx9GyOL8m7yap+joG13aljDa2OKpQg+pYvdwft+k1K9di
 8yPF+qA043UUR7dSsjmTbiCcjZy2eySdCmfOAkEG4inSgxNoM7GBs3MuwZo/veCD
 v5WssJqWDbLXtqKn5Uo2bvGWiEcf0xtwOAqhSpbaup3dQFJSWMEenBTtA9UlxFhk
 6gdY62O+7k6N0thkxXyLNGkgaGzexZAsK7dM6XSDB+PqD+OSNJS7dvmxZM8tuaRn
 rvCM1XWcNeN/dpnLbgwCR12efkwWtJoqqUZUUp/tFFaTo8HriqeAIYk7obnR8s9n
 S5x9LeueQGNgaxXJzVdh481YKG/1lqjG/a06HbVgYS4XQvtdA+4khalOefJv10tm
 Nkg8+4/8pMthWJfhhlfPUgWFXOXFF2AGPG4su2XwKuFXypO8599lzi7gUQaEZu2U
 7caqoWP69KsKvK5iAAmA4DQ2rcsgHd44NXx/8Jjes9ma8knlYjrf42dBH6AZMQBG
 69I9sJ1cyqusBwx72NPN
 =WeDQ
 -----END PGP SIGNATURE-----

Merge tag 'dt2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull arm-soc device tree conversions (part 2) from Olof Johansson:
 "These continue the device tree work from part 1, this set is for the
  tegra, mxs and imx platforms, all of which have dependencies on clock
  or pinctrl changes submitted earlier."

Fix up trivial conflicts due to nearby changes in
drivers/{gpio/gpio,i2c/busses/i2c}-mxs.c

* tag 'dt2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (73 commits)
  ARM: dt: tegra: invert status=disable vs status=okay
  ARM: dt: tegra: consistent basic property ordering
  ARM: dt: tegra: sort nodes based on bus order
  ARM: dt: tegra: remove duplicate device_type property
  ARM: dt: tegra: consistenly use lower-case for hex constants
  ARM: dt: tegra: format regs properties consistently
  ARM: dt: tegra: gpio comment cleanup
  ARM: dt: tegra: remove unnecessary unit addresses
  ARM: dt: tegra: whitespace cleanup
  ARM: dt: tegra cardhu: fix typo in SDHCI node name
  ARM: dt: tegra: cardhu: register core regulator tps62361
  ARM: dt: tegra30.dtsi: Add SMMU node
  ARM: dt: tegra20.dtsi: Add GART node
  ARM: dt: tegra30.dtsi: Add Memory Controller(MC) nodes
  ARM: dt: tegra20.dtsi: Add Memory Controller(MC) nodes
  ARM: dt: tegra: Add device tree support for AHB
  ARM: dts: enable audio support for imx28-evk
  ARM: dts: enable i2c device for imx28-evk
  i2c: mxs: add device tree probe support
  ARM: dts: enable mmc for imx28-evk
  ...
2012-05-26 12:57:47 -07:00

782 lines
20 KiB
C

/*
* Copyright 2011 Freescale Semiconductor, Inc. All Rights Reserved.
*
* Refer to drivers/dma/imx-sdma.c
*
* 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.
*/
#include <linux/init.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/semaphore.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/dmaengine.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/fsl/mxs-dma.h>
#include <linux/stmp_device.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <asm/irq.h>
#include <mach/mxs.h>
#include "dmaengine.h"
/*
* NOTE: The term "PIO" throughout the mxs-dma implementation means
* PIO mode of mxs apbh-dma and apbx-dma. With this working mode,
* dma can program the controller registers of peripheral devices.
*/
#define dma_is_apbh(mxs_dma) ((mxs_dma)->type == MXS_DMA_APBH)
#define apbh_is_old(mxs_dma) ((mxs_dma)->dev_id == IMX23_DMA)
#define HW_APBHX_CTRL0 0x000
#define BM_APBH_CTRL0_APB_BURST8_EN (1 << 29)
#define BM_APBH_CTRL0_APB_BURST_EN (1 << 28)
#define BP_APBH_CTRL0_RESET_CHANNEL 16
#define HW_APBHX_CTRL1 0x010
#define HW_APBHX_CTRL2 0x020
#define HW_APBHX_CHANNEL_CTRL 0x030
#define BP_APBHX_CHANNEL_CTRL_RESET_CHANNEL 16
/*
* The offset of NXTCMDAR register is different per both dma type and version,
* while stride for each channel is all the same 0x70.
*/
#define HW_APBHX_CHn_NXTCMDAR(d, n) \
(((dma_is_apbh(d) && apbh_is_old(d)) ? 0x050 : 0x110) + (n) * 0x70)
#define HW_APBHX_CHn_SEMA(d, n) \
(((dma_is_apbh(d) && apbh_is_old(d)) ? 0x080 : 0x140) + (n) * 0x70)
/*
* ccw bits definitions
*
* COMMAND: 0..1 (2)
* CHAIN: 2 (1)
* IRQ: 3 (1)
* NAND_LOCK: 4 (1) - not implemented
* NAND_WAIT4READY: 5 (1) - not implemented
* DEC_SEM: 6 (1)
* WAIT4END: 7 (1)
* HALT_ON_TERMINATE: 8 (1)
* TERMINATE_FLUSH: 9 (1)
* RESERVED: 10..11 (2)
* PIO_NUM: 12..15 (4)
*/
#define BP_CCW_COMMAND 0
#define BM_CCW_COMMAND (3 << 0)
#define CCW_CHAIN (1 << 2)
#define CCW_IRQ (1 << 3)
#define CCW_DEC_SEM (1 << 6)
#define CCW_WAIT4END (1 << 7)
#define CCW_HALT_ON_TERM (1 << 8)
#define CCW_TERM_FLUSH (1 << 9)
#define BP_CCW_PIO_NUM 12
#define BM_CCW_PIO_NUM (0xf << 12)
#define BF_CCW(value, field) (((value) << BP_CCW_##field) & BM_CCW_##field)
#define MXS_DMA_CMD_NO_XFER 0
#define MXS_DMA_CMD_WRITE 1
#define MXS_DMA_CMD_READ 2
#define MXS_DMA_CMD_DMA_SENSE 3 /* not implemented */
struct mxs_dma_ccw {
u32 next;
u16 bits;
u16 xfer_bytes;
#define MAX_XFER_BYTES 0xff00
u32 bufaddr;
#define MXS_PIO_WORDS 16
u32 pio_words[MXS_PIO_WORDS];
};
#define NUM_CCW (int)(PAGE_SIZE / sizeof(struct mxs_dma_ccw))
struct mxs_dma_chan {
struct mxs_dma_engine *mxs_dma;
struct dma_chan chan;
struct dma_async_tx_descriptor desc;
struct tasklet_struct tasklet;
int chan_irq;
struct mxs_dma_ccw *ccw;
dma_addr_t ccw_phys;
int desc_count;
enum dma_status status;
unsigned int flags;
#define MXS_DMA_SG_LOOP (1 << 0)
};
#define MXS_DMA_CHANNELS 16
#define MXS_DMA_CHANNELS_MASK 0xffff
enum mxs_dma_devtype {
MXS_DMA_APBH,
MXS_DMA_APBX,
};
enum mxs_dma_id {
IMX23_DMA,
IMX28_DMA,
};
struct mxs_dma_engine {
enum mxs_dma_id dev_id;
enum mxs_dma_devtype type;
void __iomem *base;
struct clk *clk;
struct dma_device dma_device;
struct device_dma_parameters dma_parms;
struct mxs_dma_chan mxs_chans[MXS_DMA_CHANNELS];
};
struct mxs_dma_type {
enum mxs_dma_id id;
enum mxs_dma_devtype type;
};
static struct mxs_dma_type mxs_dma_types[] = {
{
.id = IMX23_DMA,
.type = MXS_DMA_APBH,
}, {
.id = IMX23_DMA,
.type = MXS_DMA_APBX,
}, {
.id = IMX28_DMA,
.type = MXS_DMA_APBH,
}, {
.id = IMX28_DMA,
.type = MXS_DMA_APBX,
}
};
static struct platform_device_id mxs_dma_ids[] = {
{
.name = "imx23-dma-apbh",
.driver_data = (kernel_ulong_t) &mxs_dma_types[0],
}, {
.name = "imx23-dma-apbx",
.driver_data = (kernel_ulong_t) &mxs_dma_types[1],
}, {
.name = "imx28-dma-apbh",
.driver_data = (kernel_ulong_t) &mxs_dma_types[2],
}, {
.name = "imx28-dma-apbx",
.driver_data = (kernel_ulong_t) &mxs_dma_types[3],
}, {
/* end of list */
}
};
static const struct of_device_id mxs_dma_dt_ids[] = {
{ .compatible = "fsl,imx23-dma-apbh", .data = &mxs_dma_ids[0], },
{ .compatible = "fsl,imx23-dma-apbx", .data = &mxs_dma_ids[1], },
{ .compatible = "fsl,imx28-dma-apbh", .data = &mxs_dma_ids[2], },
{ .compatible = "fsl,imx28-dma-apbx", .data = &mxs_dma_ids[3], },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, mxs_dma_dt_ids);
static struct mxs_dma_chan *to_mxs_dma_chan(struct dma_chan *chan)
{
return container_of(chan, struct mxs_dma_chan, chan);
}
int mxs_dma_is_apbh(struct dma_chan *chan)
{
struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
return dma_is_apbh(mxs_dma);
}
int mxs_dma_is_apbx(struct dma_chan *chan)
{
struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
return !dma_is_apbh(mxs_dma);
}
static void mxs_dma_reset_chan(struct mxs_dma_chan *mxs_chan)
{
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
int chan_id = mxs_chan->chan.chan_id;
if (dma_is_apbh(mxs_dma) && apbh_is_old(mxs_dma))
writel(1 << (chan_id + BP_APBH_CTRL0_RESET_CHANNEL),
mxs_dma->base + HW_APBHX_CTRL0 + STMP_OFFSET_REG_SET);
else
writel(1 << (chan_id + BP_APBHX_CHANNEL_CTRL_RESET_CHANNEL),
mxs_dma->base + HW_APBHX_CHANNEL_CTRL + STMP_OFFSET_REG_SET);
}
static void mxs_dma_enable_chan(struct mxs_dma_chan *mxs_chan)
{
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
int chan_id = mxs_chan->chan.chan_id;
/* set cmd_addr up */
writel(mxs_chan->ccw_phys,
mxs_dma->base + HW_APBHX_CHn_NXTCMDAR(mxs_dma, chan_id));
/* write 1 to SEMA to kick off the channel */
writel(1, mxs_dma->base + HW_APBHX_CHn_SEMA(mxs_dma, chan_id));
}
static void mxs_dma_disable_chan(struct mxs_dma_chan *mxs_chan)
{
mxs_chan->status = DMA_SUCCESS;
}
static void mxs_dma_pause_chan(struct mxs_dma_chan *mxs_chan)
{
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
int chan_id = mxs_chan->chan.chan_id;
/* freeze the channel */
if (dma_is_apbh(mxs_dma) && apbh_is_old(mxs_dma))
writel(1 << chan_id,
mxs_dma->base + HW_APBHX_CTRL0 + STMP_OFFSET_REG_SET);
else
writel(1 << chan_id,
mxs_dma->base + HW_APBHX_CHANNEL_CTRL + STMP_OFFSET_REG_SET);
mxs_chan->status = DMA_PAUSED;
}
static void mxs_dma_resume_chan(struct mxs_dma_chan *mxs_chan)
{
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
int chan_id = mxs_chan->chan.chan_id;
/* unfreeze the channel */
if (dma_is_apbh(mxs_dma) && apbh_is_old(mxs_dma))
writel(1 << chan_id,
mxs_dma->base + HW_APBHX_CTRL0 + STMP_OFFSET_REG_CLR);
else
writel(1 << chan_id,
mxs_dma->base + HW_APBHX_CHANNEL_CTRL + STMP_OFFSET_REG_CLR);
mxs_chan->status = DMA_IN_PROGRESS;
}
static dma_cookie_t mxs_dma_tx_submit(struct dma_async_tx_descriptor *tx)
{
return dma_cookie_assign(tx);
}
static void mxs_dma_tasklet(unsigned long data)
{
struct mxs_dma_chan *mxs_chan = (struct mxs_dma_chan *) data;
if (mxs_chan->desc.callback)
mxs_chan->desc.callback(mxs_chan->desc.callback_param);
}
static irqreturn_t mxs_dma_int_handler(int irq, void *dev_id)
{
struct mxs_dma_engine *mxs_dma = dev_id;
u32 stat1, stat2;
/* completion status */
stat1 = readl(mxs_dma->base + HW_APBHX_CTRL1);
stat1 &= MXS_DMA_CHANNELS_MASK;
writel(stat1, mxs_dma->base + HW_APBHX_CTRL1 + STMP_OFFSET_REG_CLR);
/* error status */
stat2 = readl(mxs_dma->base + HW_APBHX_CTRL2);
writel(stat2, mxs_dma->base + HW_APBHX_CTRL2 + STMP_OFFSET_REG_CLR);
/*
* When both completion and error of termination bits set at the
* same time, we do not take it as an error. IOW, it only becomes
* an error we need to handle here in case of either it's (1) a bus
* error or (2) a termination error with no completion.
*/
stat2 = ((stat2 >> MXS_DMA_CHANNELS) & stat2) | /* (1) */
(~(stat2 >> MXS_DMA_CHANNELS) & stat2 & ~stat1); /* (2) */
/* combine error and completion status for checking */
stat1 = (stat2 << MXS_DMA_CHANNELS) | stat1;
while (stat1) {
int channel = fls(stat1) - 1;
struct mxs_dma_chan *mxs_chan =
&mxs_dma->mxs_chans[channel % MXS_DMA_CHANNELS];
if (channel >= MXS_DMA_CHANNELS) {
dev_dbg(mxs_dma->dma_device.dev,
"%s: error in channel %d\n", __func__,
channel - MXS_DMA_CHANNELS);
mxs_chan->status = DMA_ERROR;
mxs_dma_reset_chan(mxs_chan);
} else {
if (mxs_chan->flags & MXS_DMA_SG_LOOP)
mxs_chan->status = DMA_IN_PROGRESS;
else
mxs_chan->status = DMA_SUCCESS;
}
stat1 &= ~(1 << channel);
if (mxs_chan->status == DMA_SUCCESS)
dma_cookie_complete(&mxs_chan->desc);
/* schedule tasklet on this channel */
tasklet_schedule(&mxs_chan->tasklet);
}
return IRQ_HANDLED;
}
static int mxs_dma_alloc_chan_resources(struct dma_chan *chan)
{
struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
struct mxs_dma_data *data = chan->private;
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
int ret;
if (!data)
return -EINVAL;
mxs_chan->chan_irq = data->chan_irq;
mxs_chan->ccw = dma_alloc_coherent(mxs_dma->dma_device.dev, PAGE_SIZE,
&mxs_chan->ccw_phys, GFP_KERNEL);
if (!mxs_chan->ccw) {
ret = -ENOMEM;
goto err_alloc;
}
memset(mxs_chan->ccw, 0, PAGE_SIZE);
if (mxs_chan->chan_irq != NO_IRQ) {
ret = request_irq(mxs_chan->chan_irq, mxs_dma_int_handler,
0, "mxs-dma", mxs_dma);
if (ret)
goto err_irq;
}
ret = clk_prepare_enable(mxs_dma->clk);
if (ret)
goto err_clk;
mxs_dma_reset_chan(mxs_chan);
dma_async_tx_descriptor_init(&mxs_chan->desc, chan);
mxs_chan->desc.tx_submit = mxs_dma_tx_submit;
/* the descriptor is ready */
async_tx_ack(&mxs_chan->desc);
return 0;
err_clk:
free_irq(mxs_chan->chan_irq, mxs_dma);
err_irq:
dma_free_coherent(mxs_dma->dma_device.dev, PAGE_SIZE,
mxs_chan->ccw, mxs_chan->ccw_phys);
err_alloc:
return ret;
}
static void mxs_dma_free_chan_resources(struct dma_chan *chan)
{
struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
mxs_dma_disable_chan(mxs_chan);
free_irq(mxs_chan->chan_irq, mxs_dma);
dma_free_coherent(mxs_dma->dma_device.dev, PAGE_SIZE,
mxs_chan->ccw, mxs_chan->ccw_phys);
clk_disable_unprepare(mxs_dma->clk);
}
/*
* How to use the flags for ->device_prep_slave_sg() :
* [1] If there is only one DMA command in the DMA chain, the code should be:
* ......
* ->device_prep_slave_sg(DMA_CTRL_ACK);
* ......
* [2] If there are two DMA commands in the DMA chain, the code should be
* ......
* ->device_prep_slave_sg(0);
* ......
* ->device_prep_slave_sg(DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
* ......
* [3] If there are more than two DMA commands in the DMA chain, the code
* should be:
* ......
* ->device_prep_slave_sg(0); // First
* ......
* ->device_prep_slave_sg(DMA_PREP_INTERRUPT [| DMA_CTRL_ACK]);
* ......
* ->device_prep_slave_sg(DMA_PREP_INTERRUPT | DMA_CTRL_ACK); // Last
* ......
*/
static struct dma_async_tx_descriptor *mxs_dma_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 mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
struct mxs_dma_ccw *ccw;
struct scatterlist *sg;
int i, j;
u32 *pio;
bool append = flags & DMA_PREP_INTERRUPT;
int idx = append ? mxs_chan->desc_count : 0;
if (mxs_chan->status == DMA_IN_PROGRESS && !append)
return NULL;
if (sg_len + (append ? idx : 0) > NUM_CCW) {
dev_err(mxs_dma->dma_device.dev,
"maximum number of sg exceeded: %d > %d\n",
sg_len, NUM_CCW);
goto err_out;
}
mxs_chan->status = DMA_IN_PROGRESS;
mxs_chan->flags = 0;
/*
* If the sg is prepared with append flag set, the sg
* will be appended to the last prepared sg.
*/
if (append) {
BUG_ON(idx < 1);
ccw = &mxs_chan->ccw[idx - 1];
ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * idx;
ccw->bits |= CCW_CHAIN;
ccw->bits &= ~CCW_IRQ;
ccw->bits &= ~CCW_DEC_SEM;
} else {
idx = 0;
}
if (direction == DMA_TRANS_NONE) {
ccw = &mxs_chan->ccw[idx++];
pio = (u32 *) sgl;
for (j = 0; j < sg_len;)
ccw->pio_words[j++] = *pio++;
ccw->bits = 0;
ccw->bits |= CCW_IRQ;
ccw->bits |= CCW_DEC_SEM;
if (flags & DMA_CTRL_ACK)
ccw->bits |= CCW_WAIT4END;
ccw->bits |= CCW_HALT_ON_TERM;
ccw->bits |= CCW_TERM_FLUSH;
ccw->bits |= BF_CCW(sg_len, PIO_NUM);
ccw->bits |= BF_CCW(MXS_DMA_CMD_NO_XFER, COMMAND);
} else {
for_each_sg(sgl, sg, sg_len, i) {
if (sg_dma_len(sg) > MAX_XFER_BYTES) {
dev_err(mxs_dma->dma_device.dev, "maximum bytes for sg entry exceeded: %d > %d\n",
sg_dma_len(sg), MAX_XFER_BYTES);
goto err_out;
}
ccw = &mxs_chan->ccw[idx++];
ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * idx;
ccw->bufaddr = sg->dma_address;
ccw->xfer_bytes = sg_dma_len(sg);
ccw->bits = 0;
ccw->bits |= CCW_CHAIN;
ccw->bits |= CCW_HALT_ON_TERM;
ccw->bits |= CCW_TERM_FLUSH;
ccw->bits |= BF_CCW(direction == DMA_DEV_TO_MEM ?
MXS_DMA_CMD_WRITE : MXS_DMA_CMD_READ,
COMMAND);
if (i + 1 == sg_len) {
ccw->bits &= ~CCW_CHAIN;
ccw->bits |= CCW_IRQ;
ccw->bits |= CCW_DEC_SEM;
if (flags & DMA_CTRL_ACK)
ccw->bits |= CCW_WAIT4END;
}
}
}
mxs_chan->desc_count = idx;
return &mxs_chan->desc;
err_out:
mxs_chan->status = DMA_ERROR;
return NULL;
}
static struct dma_async_tx_descriptor *mxs_dma_prep_dma_cyclic(
struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
size_t period_len, enum dma_transfer_direction direction,
void *context)
{
struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
int num_periods = buf_len / period_len;
int i = 0, buf = 0;
if (mxs_chan->status == DMA_IN_PROGRESS)
return NULL;
mxs_chan->status = DMA_IN_PROGRESS;
mxs_chan->flags |= MXS_DMA_SG_LOOP;
if (num_periods > NUM_CCW) {
dev_err(mxs_dma->dma_device.dev,
"maximum number of sg exceeded: %d > %d\n",
num_periods, NUM_CCW);
goto err_out;
}
if (period_len > MAX_XFER_BYTES) {
dev_err(mxs_dma->dma_device.dev,
"maximum period size exceeded: %d > %d\n",
period_len, MAX_XFER_BYTES);
goto err_out;
}
while (buf < buf_len) {
struct mxs_dma_ccw *ccw = &mxs_chan->ccw[i];
if (i + 1 == num_periods)
ccw->next = mxs_chan->ccw_phys;
else
ccw->next = mxs_chan->ccw_phys + sizeof(*ccw) * (i + 1);
ccw->bufaddr = dma_addr;
ccw->xfer_bytes = period_len;
ccw->bits = 0;
ccw->bits |= CCW_CHAIN;
ccw->bits |= CCW_IRQ;
ccw->bits |= CCW_HALT_ON_TERM;
ccw->bits |= CCW_TERM_FLUSH;
ccw->bits |= BF_CCW(direction == DMA_DEV_TO_MEM ?
MXS_DMA_CMD_WRITE : MXS_DMA_CMD_READ, COMMAND);
dma_addr += period_len;
buf += period_len;
i++;
}
mxs_chan->desc_count = i;
return &mxs_chan->desc;
err_out:
mxs_chan->status = DMA_ERROR;
return NULL;
}
static int mxs_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
unsigned long arg)
{
struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
int ret = 0;
switch (cmd) {
case DMA_TERMINATE_ALL:
mxs_dma_reset_chan(mxs_chan);
mxs_dma_disable_chan(mxs_chan);
break;
case DMA_PAUSE:
mxs_dma_pause_chan(mxs_chan);
break;
case DMA_RESUME:
mxs_dma_resume_chan(mxs_chan);
break;
default:
ret = -ENOSYS;
}
return ret;
}
static enum dma_status mxs_dma_tx_status(struct dma_chan *chan,
dma_cookie_t cookie, struct dma_tx_state *txstate)
{
struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
dma_cookie_t last_used;
last_used = chan->cookie;
dma_set_tx_state(txstate, chan->completed_cookie, last_used, 0);
return mxs_chan->status;
}
static void mxs_dma_issue_pending(struct dma_chan *chan)
{
struct mxs_dma_chan *mxs_chan = to_mxs_dma_chan(chan);
mxs_dma_enable_chan(mxs_chan);
}
static int __init mxs_dma_init(struct mxs_dma_engine *mxs_dma)
{
int ret;
ret = clk_prepare_enable(mxs_dma->clk);
if (ret)
return ret;
ret = stmp_reset_block(mxs_dma->base);
if (ret)
goto err_out;
/* enable apbh burst */
if (dma_is_apbh(mxs_dma)) {
writel(BM_APBH_CTRL0_APB_BURST_EN,
mxs_dma->base + HW_APBHX_CTRL0 + STMP_OFFSET_REG_SET);
writel(BM_APBH_CTRL0_APB_BURST8_EN,
mxs_dma->base + HW_APBHX_CTRL0 + STMP_OFFSET_REG_SET);
}
/* enable irq for all the channels */
writel(MXS_DMA_CHANNELS_MASK << MXS_DMA_CHANNELS,
mxs_dma->base + HW_APBHX_CTRL1 + STMP_OFFSET_REG_SET);
err_out:
clk_disable_unprepare(mxs_dma->clk);
return ret;
}
static int __init mxs_dma_probe(struct platform_device *pdev)
{
const struct platform_device_id *id_entry;
const struct of_device_id *of_id;
const struct mxs_dma_type *dma_type;
struct mxs_dma_engine *mxs_dma;
struct resource *iores;
int ret, i;
mxs_dma = kzalloc(sizeof(*mxs_dma), GFP_KERNEL);
if (!mxs_dma)
return -ENOMEM;
of_id = of_match_device(mxs_dma_dt_ids, &pdev->dev);
if (of_id)
id_entry = of_id->data;
else
id_entry = platform_get_device_id(pdev);
dma_type = (struct mxs_dma_type *)id_entry->driver_data;
mxs_dma->type = dma_type->type;
mxs_dma->dev_id = dma_type->id;
iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!request_mem_region(iores->start, resource_size(iores),
pdev->name)) {
ret = -EBUSY;
goto err_request_region;
}
mxs_dma->base = ioremap(iores->start, resource_size(iores));
if (!mxs_dma->base) {
ret = -ENOMEM;
goto err_ioremap;
}
mxs_dma->clk = clk_get(&pdev->dev, NULL);
if (IS_ERR(mxs_dma->clk)) {
ret = PTR_ERR(mxs_dma->clk);
goto err_clk;
}
dma_cap_set(DMA_SLAVE, mxs_dma->dma_device.cap_mask);
dma_cap_set(DMA_CYCLIC, mxs_dma->dma_device.cap_mask);
INIT_LIST_HEAD(&mxs_dma->dma_device.channels);
/* Initialize channel parameters */
for (i = 0; i < MXS_DMA_CHANNELS; i++) {
struct mxs_dma_chan *mxs_chan = &mxs_dma->mxs_chans[i];
mxs_chan->mxs_dma = mxs_dma;
mxs_chan->chan.device = &mxs_dma->dma_device;
dma_cookie_init(&mxs_chan->chan);
tasklet_init(&mxs_chan->tasklet, mxs_dma_tasklet,
(unsigned long) mxs_chan);
/* Add the channel to mxs_chan list */
list_add_tail(&mxs_chan->chan.device_node,
&mxs_dma->dma_device.channels);
}
ret = mxs_dma_init(mxs_dma);
if (ret)
goto err_init;
mxs_dma->dma_device.dev = &pdev->dev;
/* mxs_dma gets 65535 bytes maximum sg size */
mxs_dma->dma_device.dev->dma_parms = &mxs_dma->dma_parms;
dma_set_max_seg_size(mxs_dma->dma_device.dev, MAX_XFER_BYTES);
mxs_dma->dma_device.device_alloc_chan_resources = mxs_dma_alloc_chan_resources;
mxs_dma->dma_device.device_free_chan_resources = mxs_dma_free_chan_resources;
mxs_dma->dma_device.device_tx_status = mxs_dma_tx_status;
mxs_dma->dma_device.device_prep_slave_sg = mxs_dma_prep_slave_sg;
mxs_dma->dma_device.device_prep_dma_cyclic = mxs_dma_prep_dma_cyclic;
mxs_dma->dma_device.device_control = mxs_dma_control;
mxs_dma->dma_device.device_issue_pending = mxs_dma_issue_pending;
ret = dma_async_device_register(&mxs_dma->dma_device);
if (ret) {
dev_err(mxs_dma->dma_device.dev, "unable to register\n");
goto err_init;
}
dev_info(mxs_dma->dma_device.dev, "initialized\n");
return 0;
err_init:
clk_put(mxs_dma->clk);
err_clk:
iounmap(mxs_dma->base);
err_ioremap:
release_mem_region(iores->start, resource_size(iores));
err_request_region:
kfree(mxs_dma);
return ret;
}
static struct platform_driver mxs_dma_driver = {
.driver = {
.name = "mxs-dma",
.of_match_table = mxs_dma_dt_ids,
},
.id_table = mxs_dma_ids,
};
static int __init mxs_dma_module_init(void)
{
return platform_driver_probe(&mxs_dma_driver, mxs_dma_probe);
}
subsys_initcall(mxs_dma_module_init);