https://github.com/torvalds/linux
Tip revision: d1db0eea852497762cab43b905b879dfcd3b8987 authored by Linus Torvalds on 28 April 2014, 02:29:27 UTC
Linux 3.15-rc3
Linux 3.15-rc3
Tip revision: d1db0ee
mmp_tdma.c
/*
* Driver For Marvell Two-channel DMA Engine
*
* Copyright: Marvell International Ltd.
*
* The code contained herein is licensed under the GNU General Public
* License. You may obtain a copy of the GNU General Public License
* Version 2 or later at the following locations:
*
*/
#include <linux/err.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/dmaengine.h>
#include <linux/platform_device.h>
#include <linux/device.h>
#include <mach/regs-icu.h>
#include <linux/platform_data/dma-mmp_tdma.h>
#include <linux/of_device.h>
#include <linux/of_dma.h>
#include "dmaengine.h"
/*
* Two-Channel DMA registers
*/
#define TDBCR 0x00 /* Byte Count */
#define TDSAR 0x10 /* Src Addr */
#define TDDAR 0x20 /* Dst Addr */
#define TDNDPR 0x30 /* Next Desc */
#define TDCR 0x40 /* Control */
#define TDCP 0x60 /* Priority*/
#define TDCDPR 0x70 /* Current Desc */
#define TDIMR 0x80 /* Int Mask */
#define TDISR 0xa0 /* Int Status */
/* Two-Channel DMA Control Register */
#define TDCR_SSZ_8_BITS (0x0 << 22) /* Sample Size */
#define TDCR_SSZ_12_BITS (0x1 << 22)
#define TDCR_SSZ_16_BITS (0x2 << 22)
#define TDCR_SSZ_20_BITS (0x3 << 22)
#define TDCR_SSZ_24_BITS (0x4 << 22)
#define TDCR_SSZ_32_BITS (0x5 << 22)
#define TDCR_SSZ_SHIFT (0x1 << 22)
#define TDCR_SSZ_MASK (0x7 << 22)
#define TDCR_SSPMOD (0x1 << 21) /* SSP MOD */
#define TDCR_ABR (0x1 << 20) /* Channel Abort */
#define TDCR_CDE (0x1 << 17) /* Close Desc Enable */
#define TDCR_PACKMOD (0x1 << 16) /* Pack Mode (ADMA Only) */
#define TDCR_CHANACT (0x1 << 14) /* Channel Active */
#define TDCR_FETCHND (0x1 << 13) /* Fetch Next Desc */
#define TDCR_CHANEN (0x1 << 12) /* Channel Enable */
#define TDCR_INTMODE (0x1 << 10) /* Interrupt Mode */
#define TDCR_CHAINMOD (0x1 << 9) /* Chain Mode */
#define TDCR_BURSTSZ_MSK (0x7 << 6) /* Burst Size */
#define TDCR_BURSTSZ_4B (0x0 << 6)
#define TDCR_BURSTSZ_8B (0x1 << 6)
#define TDCR_BURSTSZ_16B (0x3 << 6)
#define TDCR_BURSTSZ_32B (0x6 << 6)
#define TDCR_BURSTSZ_64B (0x7 << 6)
#define TDCR_BURSTSZ_SQU_1B (0x5 << 6)
#define TDCR_BURSTSZ_SQU_2B (0x6 << 6)
#define TDCR_BURSTSZ_SQU_4B (0x0 << 6)
#define TDCR_BURSTSZ_SQU_8B (0x1 << 6)
#define TDCR_BURSTSZ_SQU_16B (0x3 << 6)
#define TDCR_BURSTSZ_SQU_32B (0x7 << 6)
#define TDCR_BURSTSZ_128B (0x5 << 6)
#define TDCR_DSTDIR_MSK (0x3 << 4) /* Dst Direction */
#define TDCR_DSTDIR_ADDR_HOLD (0x2 << 4) /* Dst Addr Hold */
#define TDCR_DSTDIR_ADDR_INC (0x0 << 4) /* Dst Addr Increment */
#define TDCR_SRCDIR_MSK (0x3 << 2) /* Src Direction */
#define TDCR_SRCDIR_ADDR_HOLD (0x2 << 2) /* Src Addr Hold */
#define TDCR_SRCDIR_ADDR_INC (0x0 << 2) /* Src Addr Increment */
#define TDCR_DSTDESCCONT (0x1 << 1)
#define TDCR_SRCDESTCONT (0x1 << 0)
/* Two-Channel DMA Int Mask Register */
#define TDIMR_COMP (0x1 << 0)
/* Two-Channel DMA Int Status Register */
#define TDISR_COMP (0x1 << 0)
/*
* Two-Channel DMA Descriptor Struct
* NOTE: desc's buf must be aligned to 16 bytes.
*/
struct mmp_tdma_desc {
u32 byte_cnt;
u32 src_addr;
u32 dst_addr;
u32 nxt_desc;
};
enum mmp_tdma_type {
MMP_AUD_TDMA = 0,
PXA910_SQU,
};
#define TDMA_ALIGNMENT 3
#define TDMA_MAX_XFER_BYTES SZ_64K
struct mmp_tdma_chan {
struct device *dev;
struct dma_chan chan;
struct dma_async_tx_descriptor desc;
struct tasklet_struct tasklet;
struct mmp_tdma_desc *desc_arr;
phys_addr_t desc_arr_phys;
int desc_num;
enum dma_transfer_direction dir;
dma_addr_t dev_addr;
u32 burst_sz;
enum dma_slave_buswidth buswidth;
enum dma_status status;
int idx;
enum mmp_tdma_type type;
int irq;
void __iomem *reg_base;
size_t buf_len;
size_t period_len;
size_t pos;
struct gen_pool *pool;
};
#define TDMA_CHANNEL_NUM 2
struct mmp_tdma_device {
struct device *dev;
void __iomem *base;
struct dma_device device;
struct mmp_tdma_chan *tdmac[TDMA_CHANNEL_NUM];
};
#define to_mmp_tdma_chan(dchan) container_of(dchan, struct mmp_tdma_chan, chan)
static void mmp_tdma_chan_set_desc(struct mmp_tdma_chan *tdmac, dma_addr_t phys)
{
writel(phys, tdmac->reg_base + TDNDPR);
writel(readl(tdmac->reg_base + TDCR) | TDCR_FETCHND,
tdmac->reg_base + TDCR);
}
static void mmp_tdma_enable_chan(struct mmp_tdma_chan *tdmac)
{
/* enable irq */
writel(TDIMR_COMP, tdmac->reg_base + TDIMR);
/* enable dma chan */
writel(readl(tdmac->reg_base + TDCR) | TDCR_CHANEN,
tdmac->reg_base + TDCR);
tdmac->status = DMA_IN_PROGRESS;
}
static void mmp_tdma_disable_chan(struct mmp_tdma_chan *tdmac)
{
writel(readl(tdmac->reg_base + TDCR) & ~TDCR_CHANEN,
tdmac->reg_base + TDCR);
/* disable irq */
writel(0, tdmac->reg_base + TDIMR);
tdmac->status = DMA_COMPLETE;
}
static void mmp_tdma_resume_chan(struct mmp_tdma_chan *tdmac)
{
writel(readl(tdmac->reg_base + TDCR) | TDCR_CHANEN,
tdmac->reg_base + TDCR);
tdmac->status = DMA_IN_PROGRESS;
}
static void mmp_tdma_pause_chan(struct mmp_tdma_chan *tdmac)
{
writel(readl(tdmac->reg_base + TDCR) & ~TDCR_CHANEN,
tdmac->reg_base + TDCR);
tdmac->status = DMA_PAUSED;
}
static int mmp_tdma_config_chan(struct mmp_tdma_chan *tdmac)
{
unsigned int tdcr = 0;
mmp_tdma_disable_chan(tdmac);
if (tdmac->dir == DMA_MEM_TO_DEV)
tdcr = TDCR_DSTDIR_ADDR_HOLD | TDCR_SRCDIR_ADDR_INC;
else if (tdmac->dir == DMA_DEV_TO_MEM)
tdcr = TDCR_SRCDIR_ADDR_HOLD | TDCR_DSTDIR_ADDR_INC;
if (tdmac->type == MMP_AUD_TDMA) {
tdcr |= TDCR_PACKMOD;
switch (tdmac->burst_sz) {
case 4:
tdcr |= TDCR_BURSTSZ_4B;
break;
case 8:
tdcr |= TDCR_BURSTSZ_8B;
break;
case 16:
tdcr |= TDCR_BURSTSZ_16B;
break;
case 32:
tdcr |= TDCR_BURSTSZ_32B;
break;
case 64:
tdcr |= TDCR_BURSTSZ_64B;
break;
case 128:
tdcr |= TDCR_BURSTSZ_128B;
break;
default:
dev_err(tdmac->dev, "mmp_tdma: unknown burst size.\n");
return -EINVAL;
}
switch (tdmac->buswidth) {
case DMA_SLAVE_BUSWIDTH_1_BYTE:
tdcr |= TDCR_SSZ_8_BITS;
break;
case DMA_SLAVE_BUSWIDTH_2_BYTES:
tdcr |= TDCR_SSZ_16_BITS;
break;
case DMA_SLAVE_BUSWIDTH_4_BYTES:
tdcr |= TDCR_SSZ_32_BITS;
break;
default:
dev_err(tdmac->dev, "mmp_tdma: unknown bus size.\n");
return -EINVAL;
}
} else if (tdmac->type == PXA910_SQU) {
tdcr |= TDCR_SSPMOD;
switch (tdmac->burst_sz) {
case 1:
tdcr |= TDCR_BURSTSZ_SQU_1B;
break;
case 2:
tdcr |= TDCR_BURSTSZ_SQU_2B;
break;
case 4:
tdcr |= TDCR_BURSTSZ_SQU_4B;
break;
case 8:
tdcr |= TDCR_BURSTSZ_SQU_8B;
break;
case 16:
tdcr |= TDCR_BURSTSZ_SQU_16B;
break;
case 32:
tdcr |= TDCR_BURSTSZ_SQU_32B;
break;
default:
dev_err(tdmac->dev, "mmp_tdma: unknown burst size.\n");
return -EINVAL;
}
}
writel(tdcr, tdmac->reg_base + TDCR);
return 0;
}
static int mmp_tdma_clear_chan_irq(struct mmp_tdma_chan *tdmac)
{
u32 reg = readl(tdmac->reg_base + TDISR);
if (reg & TDISR_COMP) {
/* clear irq */
reg &= ~TDISR_COMP;
writel(reg, tdmac->reg_base + TDISR);
return 0;
}
return -EAGAIN;
}
static irqreturn_t mmp_tdma_chan_handler(int irq, void *dev_id)
{
struct mmp_tdma_chan *tdmac = dev_id;
if (mmp_tdma_clear_chan_irq(tdmac) == 0) {
tdmac->pos = (tdmac->pos + tdmac->period_len) % tdmac->buf_len;
tasklet_schedule(&tdmac->tasklet);
return IRQ_HANDLED;
} else
return IRQ_NONE;
}
static irqreturn_t mmp_tdma_int_handler(int irq, void *dev_id)
{
struct mmp_tdma_device *tdev = dev_id;
int i, ret;
int irq_num = 0;
for (i = 0; i < TDMA_CHANNEL_NUM; i++) {
struct mmp_tdma_chan *tdmac = tdev->tdmac[i];
ret = mmp_tdma_chan_handler(irq, tdmac);
if (ret == IRQ_HANDLED)
irq_num++;
}
if (irq_num)
return IRQ_HANDLED;
else
return IRQ_NONE;
}
static void dma_do_tasklet(unsigned long data)
{
struct mmp_tdma_chan *tdmac = (struct mmp_tdma_chan *)data;
if (tdmac->desc.callback)
tdmac->desc.callback(tdmac->desc.callback_param);
}
static void mmp_tdma_free_descriptor(struct mmp_tdma_chan *tdmac)
{
struct gen_pool *gpool;
int size = tdmac->desc_num * sizeof(struct mmp_tdma_desc);
gpool = tdmac->pool;
if (tdmac->desc_arr)
gen_pool_free(gpool, (unsigned long)tdmac->desc_arr,
size);
tdmac->desc_arr = NULL;
return;
}
static dma_cookie_t mmp_tdma_tx_submit(struct dma_async_tx_descriptor *tx)
{
struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(tx->chan);
mmp_tdma_chan_set_desc(tdmac, tdmac->desc_arr_phys);
return 0;
}
static int mmp_tdma_alloc_chan_resources(struct dma_chan *chan)
{
struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
int ret;
dma_async_tx_descriptor_init(&tdmac->desc, chan);
tdmac->desc.tx_submit = mmp_tdma_tx_submit;
if (tdmac->irq) {
ret = devm_request_irq(tdmac->dev, tdmac->irq,
mmp_tdma_chan_handler, 0, "tdma", tdmac);
if (ret)
return ret;
}
return 1;
}
static void mmp_tdma_free_chan_resources(struct dma_chan *chan)
{
struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
if (tdmac->irq)
devm_free_irq(tdmac->dev, tdmac->irq, tdmac);
mmp_tdma_free_descriptor(tdmac);
return;
}
struct mmp_tdma_desc *mmp_tdma_alloc_descriptor(struct mmp_tdma_chan *tdmac)
{
struct gen_pool *gpool;
int size = tdmac->desc_num * sizeof(struct mmp_tdma_desc);
gpool = tdmac->pool;
if (!gpool)
return NULL;
tdmac->desc_arr = gen_pool_dma_alloc(gpool, size, &tdmac->desc_arr_phys);
return tdmac->desc_arr;
}
static struct dma_async_tx_descriptor *mmp_tdma_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,
unsigned long flags, void *context)
{
struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
struct mmp_tdma_desc *desc;
int num_periods = buf_len / period_len;
int i = 0, buf = 0;
if (tdmac->status != DMA_COMPLETE)
return NULL;
if (period_len > TDMA_MAX_XFER_BYTES) {
dev_err(tdmac->dev,
"maximum period size exceeded: %d > %d\n",
period_len, TDMA_MAX_XFER_BYTES);
goto err_out;
}
tdmac->status = DMA_IN_PROGRESS;
tdmac->desc_num = num_periods;
desc = mmp_tdma_alloc_descriptor(tdmac);
if (!desc)
goto err_out;
while (buf < buf_len) {
desc = &tdmac->desc_arr[i];
if (i + 1 == num_periods)
desc->nxt_desc = tdmac->desc_arr_phys;
else
desc->nxt_desc = tdmac->desc_arr_phys +
sizeof(*desc) * (i + 1);
if (direction == DMA_MEM_TO_DEV) {
desc->src_addr = dma_addr;
desc->dst_addr = tdmac->dev_addr;
} else {
desc->src_addr = tdmac->dev_addr;
desc->dst_addr = dma_addr;
}
desc->byte_cnt = period_len;
dma_addr += period_len;
buf += period_len;
i++;
}
tdmac->buf_len = buf_len;
tdmac->period_len = period_len;
tdmac->pos = 0;
return &tdmac->desc;
err_out:
tdmac->status = DMA_ERROR;
return NULL;
}
static int mmp_tdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
unsigned long arg)
{
struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
struct dma_slave_config *dmaengine_cfg = (void *)arg;
int ret = 0;
switch (cmd) {
case DMA_TERMINATE_ALL:
mmp_tdma_disable_chan(tdmac);
break;
case DMA_PAUSE:
mmp_tdma_pause_chan(tdmac);
break;
case DMA_RESUME:
mmp_tdma_resume_chan(tdmac);
break;
case DMA_SLAVE_CONFIG:
if (dmaengine_cfg->direction == DMA_DEV_TO_MEM) {
tdmac->dev_addr = dmaengine_cfg->src_addr;
tdmac->burst_sz = dmaengine_cfg->src_maxburst;
tdmac->buswidth = dmaengine_cfg->src_addr_width;
} else {
tdmac->dev_addr = dmaengine_cfg->dst_addr;
tdmac->burst_sz = dmaengine_cfg->dst_maxburst;
tdmac->buswidth = dmaengine_cfg->dst_addr_width;
}
tdmac->dir = dmaengine_cfg->direction;
return mmp_tdma_config_chan(tdmac);
default:
ret = -ENOSYS;
}
return ret;
}
static enum dma_status mmp_tdma_tx_status(struct dma_chan *chan,
dma_cookie_t cookie, struct dma_tx_state *txstate)
{
struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
dma_set_tx_state(txstate, chan->completed_cookie, chan->cookie,
tdmac->buf_len - tdmac->pos);
return tdmac->status;
}
static void mmp_tdma_issue_pending(struct dma_chan *chan)
{
struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
mmp_tdma_enable_chan(tdmac);
}
static int mmp_tdma_remove(struct platform_device *pdev)
{
struct mmp_tdma_device *tdev = platform_get_drvdata(pdev);
dma_async_device_unregister(&tdev->device);
return 0;
}
static int mmp_tdma_chan_init(struct mmp_tdma_device *tdev,
int idx, int irq,
int type, struct gen_pool *pool)
{
struct mmp_tdma_chan *tdmac;
if (idx >= TDMA_CHANNEL_NUM) {
dev_err(tdev->dev, "too many channels for device!\n");
return -EINVAL;
}
/* alloc channel */
tdmac = devm_kzalloc(tdev->dev, sizeof(*tdmac), GFP_KERNEL);
if (!tdmac) {
dev_err(tdev->dev, "no free memory for DMA channels!\n");
return -ENOMEM;
}
if (irq)
tdmac->irq = irq;
tdmac->dev = tdev->dev;
tdmac->chan.device = &tdev->device;
tdmac->idx = idx;
tdmac->type = type;
tdmac->reg_base = tdev->base + idx * 4;
tdmac->pool = pool;
tdmac->status = DMA_COMPLETE;
tdev->tdmac[tdmac->idx] = tdmac;
tasklet_init(&tdmac->tasklet, dma_do_tasklet, (unsigned long)tdmac);
/* add the channel to tdma_chan list */
list_add_tail(&tdmac->chan.device_node,
&tdev->device.channels);
return 0;
}
struct mmp_tdma_filter_param {
struct device_node *of_node;
unsigned int chan_id;
};
static bool mmp_tdma_filter_fn(struct dma_chan *chan, void *fn_param)
{
struct mmp_tdma_filter_param *param = fn_param;
struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
struct dma_device *pdma_device = tdmac->chan.device;
if (pdma_device->dev->of_node != param->of_node)
return false;
if (chan->chan_id != param->chan_id)
return false;
return true;
}
struct dma_chan *mmp_tdma_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma)
{
struct mmp_tdma_device *tdev = ofdma->of_dma_data;
dma_cap_mask_t mask = tdev->device.cap_mask;
struct mmp_tdma_filter_param param;
if (dma_spec->args_count != 1)
return NULL;
param.of_node = ofdma->of_node;
param.chan_id = dma_spec->args[0];
if (param.chan_id >= TDMA_CHANNEL_NUM)
return NULL;
return dma_request_channel(mask, mmp_tdma_filter_fn, ¶m);
}
static struct of_device_id mmp_tdma_dt_ids[] = {
{ .compatible = "marvell,adma-1.0", .data = (void *)MMP_AUD_TDMA},
{ .compatible = "marvell,pxa910-squ", .data = (void *)PXA910_SQU},
{}
};
MODULE_DEVICE_TABLE(of, mmp_tdma_dt_ids);
static int mmp_tdma_probe(struct platform_device *pdev)
{
enum mmp_tdma_type type;
const struct of_device_id *of_id;
struct mmp_tdma_device *tdev;
struct resource *iores;
int i, ret;
int irq = 0, irq_num = 0;
int chan_num = TDMA_CHANNEL_NUM;
struct gen_pool *pool;
of_id = of_match_device(mmp_tdma_dt_ids, &pdev->dev);
if (of_id)
type = (enum mmp_tdma_type) of_id->data;
else
type = platform_get_device_id(pdev)->driver_data;
/* always have couple channels */
tdev = devm_kzalloc(&pdev->dev, sizeof(*tdev), GFP_KERNEL);
if (!tdev)
return -ENOMEM;
tdev->dev = &pdev->dev;
for (i = 0; i < chan_num; i++) {
if (platform_get_irq(pdev, i) > 0)
irq_num++;
}
iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
tdev->base = devm_ioremap_resource(&pdev->dev, iores);
if (IS_ERR(tdev->base))
return PTR_ERR(tdev->base);
INIT_LIST_HEAD(&tdev->device.channels);
if (pdev->dev.of_node)
pool = of_get_named_gen_pool(pdev->dev.of_node, "asram", 0);
else
pool = sram_get_gpool("asram");
if (!pool) {
dev_err(&pdev->dev, "asram pool not available\n");
return -ENOMEM;
}
if (irq_num != chan_num) {
irq = platform_get_irq(pdev, 0);
ret = devm_request_irq(&pdev->dev, irq,
mmp_tdma_int_handler, 0, "tdma", tdev);
if (ret)
return ret;
}
/* initialize channel parameters */
for (i = 0; i < chan_num; i++) {
irq = (irq_num != chan_num) ? 0 : platform_get_irq(pdev, i);
ret = mmp_tdma_chan_init(tdev, i, irq, type, pool);
if (ret)
return ret;
}
dma_cap_set(DMA_SLAVE, tdev->device.cap_mask);
dma_cap_set(DMA_CYCLIC, tdev->device.cap_mask);
tdev->device.dev = &pdev->dev;
tdev->device.device_alloc_chan_resources =
mmp_tdma_alloc_chan_resources;
tdev->device.device_free_chan_resources =
mmp_tdma_free_chan_resources;
tdev->device.device_prep_dma_cyclic = mmp_tdma_prep_dma_cyclic;
tdev->device.device_tx_status = mmp_tdma_tx_status;
tdev->device.device_issue_pending = mmp_tdma_issue_pending;
tdev->device.device_control = mmp_tdma_control;
tdev->device.copy_align = TDMA_ALIGNMENT;
dma_set_mask(&pdev->dev, DMA_BIT_MASK(64));
platform_set_drvdata(pdev, tdev);
ret = dma_async_device_register(&tdev->device);
if (ret) {
dev_err(tdev->device.dev, "unable to register\n");
return ret;
}
if (pdev->dev.of_node) {
ret = of_dma_controller_register(pdev->dev.of_node,
mmp_tdma_xlate, tdev);
if (ret) {
dev_err(tdev->device.dev,
"failed to register controller\n");
dma_async_device_unregister(&tdev->device);
}
}
dev_info(tdev->device.dev, "initialized\n");
return 0;
}
static const struct platform_device_id mmp_tdma_id_table[] = {
{ "mmp-adma", MMP_AUD_TDMA },
{ "pxa910-squ", PXA910_SQU },
{ },
};
static struct platform_driver mmp_tdma_driver = {
.driver = {
.name = "mmp-tdma",
.owner = THIS_MODULE,
.of_match_table = mmp_tdma_dt_ids,
},
.id_table = mmp_tdma_id_table,
.probe = mmp_tdma_probe,
.remove = mmp_tdma_remove,
};
module_platform_driver(mmp_tdma_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MMP Two-Channel DMA Driver");
MODULE_ALIAS("platform:mmp-tdma");
MODULE_AUTHOR("Leo Yan <leoy@marvell.com>");
MODULE_AUTHOR("Zhangfei Gao <zhangfei.gao@marvell.com>");