* Re: [PATCH v2 0/5] add virt-dma support for imx-sdma
2018-06-08 13:44 [PATCH v2 0/5] add virt-dma support for imx-sdma Robin Gong
@ 2018-06-08 8:43 ` Sascha Hauer
2018-06-08 9:43 ` Robin Gong
2018-06-08 13:44 ` [PATCH v2 1/5] dmaengine: imx-sdma: add virt-dma support Robin Gong
` (4 subsequent siblings)
5 siblings, 1 reply; 9+ messages in thread
From: Sascha Hauer @ 2018-06-08 8:43 UTC (permalink / raw)
To: Robin Gong
Cc: vkoul, dan.j.williams, dmaengine, linux-kernel, linux-arm-kernel,
linux-imx
On Fri, Jun 08, 2018 at 09:44:45PM +0800, Robin Gong wrote:
> The legacy sdma driver has below limitations or drawbacks:
> 1. Hardcode the max BDs number as "PAGE_SIZE / sizeof(*)", and alloc
> one page size for one channel regardless of only few BDs needed
> most time. But in few cases, the max PAGE_SIZE maybe not enough.
> 2. One SDMA channel can't stop immediatley once channel disabled which
> means SDMA interrupt may come in after this channel terminated.There
> are some patches for this corner case such as commit "2746e2c389f9",
> but not cover non-cyclic.
>
> The common virt-dma overcomes the above limitations. It can alloc bd
> dynamically and free bd once this tx transfer done. No memory wasted or
> maximum limititation here, only depends on how many memory can be requested
> from kernel. For No.2, such issue can be workaround by checking if there
> is available descript("sdmac->desc") now once the unwanted interrupt
> coming. At last the common virt-dma is easier for sdma driver maintain.
>
> Change from v1:
> 1. split v1 patch into 5 patches.
> 2. remove some unnecessary condition check.
> 3. remove unneccessary 'pending' list.
>
> Robin Gong (5):
> dmaengine: imx-sdma: add virt-dma support
> Revert "dmaengine: imx-sdma: fix pagefault when channel is disabled
> during interrupt"
> dmaengine: imx-sdma: remove usless lock
> dmaengine: imx-sdma: remove the maximum limation for bd numbers
> dmaengine: imx-sdma: add sdma_transfer_init to decrease code overlap
>
> drivers/dma/Kconfig | 1 +
> drivers/dma/imx-sdma.c | 392 ++++++++++++++++++++++++++++---------------------
> 2 files changed, 227 insertions(+), 166 deletions(-)
Please put the attached patch in front of your series. It makes the
virt-dma support patch smaller and thus easier to review.
Sascha
--------------------------------8<----------------------------------
>From a70ccdf780cc6fcddd2d06c4a3eb0123d4aba443 Mon Sep 17 00:00:00 2001
From: Sascha Hauer <s.hauer@pengutronix.de>
Date: Fri, 8 Jun 2018 10:20:18 +0200
Subject: [PATCH 1/2] dmaengine: imx-sdma: factor out a struct sdma_desc from
struct sdma_channel
This is a preparation step to make the adding of virt-dma easier.
We create a struct sdma_desc, move some fields from struct sdma_channel
there and add a pointer from the former to the latter. For now we
allocate the data statically in struct sdma_channel, but with
virt-dma support it will be dynamically allocated.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
drivers/dma/imx-sdma.c | 137 +++++++++++++++++++++++++----------------
1 file changed, 83 insertions(+), 54 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index ccd03c3cedfe..556d08712f4a 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -295,6 +295,30 @@ struct sdma_context_data {
struct sdma_engine;
+/**
+ * struct sdma_desc - descriptor structor for one transfer
+ * @vd descriptor for virt dma
+ * @num_bd max NUM_BD. number of descriptors currently handling
+ * @buf_tail ID of the buffer that was processed
+ * @buf_ptail ID of the previous buffer that was processed
+ * @period_len period length, used in cyclic.
+ * @chn_real_count the real count updated from bd->mode.count
+ * @chn_count the transfer count setuped
+ * @sdmac sdma_channel pointer
+ * @bd pointer of alloced bd
+ */
+struct sdma_desc {
+ unsigned int num_bd;
+ dma_addr_t bd_phys;
+ unsigned int buf_tail;
+ unsigned int buf_ptail;
+ unsigned int period_len;
+ unsigned int chn_real_count;
+ unsigned int chn_count;
+ struct sdma_channel *sdmac;
+ struct sdma_buffer_descriptor *bd;
+};
+
/**
* struct sdma_channel - housekeeping for a SDMA channel
*
@@ -305,11 +329,10 @@ struct sdma_engine;
* @event_id0 aka dma request line
* @event_id1 for channels that use 2 events
* @word_size peripheral access size
- * @buf_tail ID of the buffer that was processed
- * @buf_ptail ID of the previous buffer that was processed
- * @num_bd max NUM_BD. number of descriptors currently handling
*/
struct sdma_channel {
+ struct sdma_desc *desc;
+ struct sdma_desc _desc;
struct sdma_engine *sdma;
unsigned int channel;
enum dma_transfer_direction direction;
@@ -317,12 +340,6 @@ struct sdma_channel {
unsigned int event_id0;
unsigned int event_id1;
enum dma_slave_buswidth word_size;
- unsigned int buf_tail;
- unsigned int buf_ptail;
- unsigned int num_bd;
- unsigned int period_len;
- struct sdma_buffer_descriptor *bd;
- dma_addr_t bd_phys;
unsigned int pc_from_device, pc_to_device;
unsigned int device_to_device;
unsigned long flags;
@@ -332,10 +349,8 @@ struct sdma_channel {
u32 shp_addr, per_addr;
struct dma_chan chan;
spinlock_t lock;
- struct dma_async_tx_descriptor desc;
+ struct dma_async_tx_descriptor txdesc;
enum dma_status status;
- unsigned int chn_count;
- unsigned int chn_real_count;
struct tasklet_struct tasklet;
struct imx_dma_data data;
bool enabled;
@@ -398,6 +413,8 @@ struct sdma_engine {
u32 spba_start_addr;
u32 spba_end_addr;
unsigned int irq;
+ dma_addr_t bd0_phys;
+ struct sdma_buffer_descriptor *bd0;
};
static struct sdma_driver_data sdma_imx31 = {
@@ -632,7 +649,7 @@ static int sdma_run_channel0(struct sdma_engine *sdma)
static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size,
u32 address)
{
- struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
+ struct sdma_buffer_descriptor *bd0 = sdma->bd0;
void *buf_virt;
dma_addr_t buf_phys;
int ret;
@@ -707,7 +724,9 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
* call callback function.
*/
while (1) {
- bd = &sdmac->bd[sdmac->buf_tail];
+ struct sdma_desc *desc = sdmac->desc;
+
+ bd = &desc->bd[desc->buf_tail];
if (bd->mode.status & BD_DONE)
break;
@@ -723,11 +742,11 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
* the number of bytes present in the current buffer descriptor.
*/
- sdmac->chn_real_count = bd->mode.count;
+ desc->chn_real_count = bd->mode.count;
bd->mode.status |= BD_DONE;
- bd->mode.count = sdmac->period_len;
- sdmac->buf_ptail = sdmac->buf_tail;
- sdmac->buf_tail = (sdmac->buf_tail + 1) % sdmac->num_bd;
+ bd->mode.count = desc->period_len;
+ desc->buf_ptail = desc->buf_tail;
+ desc->buf_tail = (desc->buf_tail + 1) % desc->num_bd;
/*
* The callback is called from the interrupt context in order
@@ -736,7 +755,7 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
* executed.
*/
- dmaengine_desc_get_callback_invoke(&sdmac->desc, NULL);
+ dmaengine_desc_get_callback_invoke(&sdmac->txdesc, NULL);
if (error)
sdmac->status = old_status;
@@ -749,17 +768,17 @@ static void mxc_sdma_handle_channel_normal(unsigned long data)
struct sdma_buffer_descriptor *bd;
int i, error = 0;
- sdmac->chn_real_count = 0;
+ sdmac->desc->chn_real_count = 0;
/*
* non loop mode. Iterate over all descriptors, collect
* errors and call callback function
*/
- for (i = 0; i < sdmac->num_bd; i++) {
- bd = &sdmac->bd[i];
+ for (i = 0; i < sdmac->desc->num_bd; i++) {
+ bd = &sdmac->desc->bd[i];
if (bd->mode.status & (BD_DONE | BD_RROR))
error = -EIO;
- sdmac->chn_real_count += bd->mode.count;
+ sdmac->desc->chn_real_count += bd->mode.count;
}
if (error)
@@ -767,9 +786,9 @@ static void mxc_sdma_handle_channel_normal(unsigned long data)
else
sdmac->status = DMA_COMPLETE;
- dma_cookie_complete(&sdmac->desc);
+ dma_cookie_complete(&sdmac->txdesc);
- dmaengine_desc_get_callback_invoke(&sdmac->desc, NULL);
+ dmaengine_desc_get_callback_invoke(&sdmac->txdesc, NULL);
}
static irqreturn_t sdma_int_handler(int irq, void *dev_id)
@@ -897,7 +916,7 @@ static int sdma_load_context(struct sdma_channel *sdmac)
int channel = sdmac->channel;
int load_address;
struct sdma_context_data *context = sdma->context;
- struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
+ struct sdma_buffer_descriptor *bd0 = sdma->bd0;
int ret;
unsigned long flags;
@@ -1100,18 +1119,22 @@ static int sdma_set_channel_priority(struct sdma_channel *sdmac,
static int sdma_request_channel(struct sdma_channel *sdmac)
{
struct sdma_engine *sdma = sdmac->sdma;
+ struct sdma_desc *desc;
int channel = sdmac->channel;
int ret = -EBUSY;
- sdmac->bd = dma_zalloc_coherent(NULL, PAGE_SIZE, &sdmac->bd_phys,
+ sdmac->desc = &sdmac->_desc;
+ desc = sdmac->desc;
+
+ desc->bd = dma_zalloc_coherent(NULL, PAGE_SIZE, &desc->bd_phys,
GFP_KERNEL);
- if (!sdmac->bd) {
+ if (!desc->bd) {
ret = -ENOMEM;
goto out;
}
- sdma->channel_control[channel].base_bd_ptr = sdmac->bd_phys;
- sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
+ sdma->channel_control[channel].base_bd_ptr = desc->bd_phys;
+ sdma->channel_control[channel].current_bd_ptr = desc->bd_phys;
sdma_set_channel_priority(sdmac, MXC_SDMA_DEFAULT_PRIORITY);
return 0;
@@ -1176,10 +1199,10 @@ static int sdma_alloc_chan_resources(struct dma_chan *chan)
if (ret)
goto disable_clk_ahb;
- dma_async_tx_descriptor_init(&sdmac->desc, chan);
- sdmac->desc.tx_submit = sdma_tx_submit;
+ dma_async_tx_descriptor_init(&sdmac->txdesc, chan);
+ sdmac->txdesc.tx_submit = sdma_tx_submit;
/* txd.flags will be overwritten in prep funcs */
- sdmac->desc.flags = DMA_CTRL_ACK;
+ sdmac->txdesc.flags = DMA_CTRL_ACK;
return 0;
@@ -1194,6 +1217,7 @@ static void sdma_free_chan_resources(struct dma_chan *chan)
{
struct sdma_channel *sdmac = to_sdma_chan(chan);
struct sdma_engine *sdma = sdmac->sdma;
+ struct sdma_desc *desc = sdmac->desc;
sdma_disable_channel(chan);
@@ -1207,7 +1231,7 @@ static void sdma_free_chan_resources(struct dma_chan *chan)
sdma_set_channel_priority(sdmac, 0);
- dma_free_coherent(NULL, PAGE_SIZE, sdmac->bd, sdmac->bd_phys);
+ dma_free_coherent(NULL, PAGE_SIZE, desc->bd, desc->bd_phys);
clk_disable(sdma->clk_ipg);
clk_disable(sdma->clk_ahb);
@@ -1223,6 +1247,7 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
int ret, i, count;
int channel = sdmac->channel;
struct scatterlist *sg;
+ struct sdma_desc *desc = sdmac->desc;
if (sdmac->status == DMA_IN_PROGRESS)
return NULL;
@@ -1230,9 +1255,9 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
sdmac->flags = 0;
- sdmac->buf_tail = 0;
- sdmac->buf_ptail = 0;
- sdmac->chn_real_count = 0;
+ desc->buf_tail = 0;
+ desc->buf_ptail = 0;
+ desc->chn_real_count = 0;
dev_dbg(sdma->dev, "setting up %d entries for channel %d.\n",
sg_len, channel);
@@ -1249,9 +1274,9 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
goto err_out;
}
- sdmac->chn_count = 0;
+ desc->chn_count = 0;
for_each_sg(sgl, sg, sg_len, i) {
- struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
+ struct sdma_buffer_descriptor *bd = &desc->bd[i];
int param;
bd->buffer_addr = sg->dma_address;
@@ -1266,7 +1291,7 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
}
bd->mode.count = count;
- sdmac->chn_count += count;
+ desc->chn_count += count;
if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES) {
ret = -EINVAL;
@@ -1307,10 +1332,10 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
bd->mode.status = param;
}
- sdmac->num_bd = sg_len;
- sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
+ desc->num_bd = sg_len;
+ sdma->channel_control[channel].current_bd_ptr = desc->bd_phys;
- return &sdmac->desc;
+ return &sdmac->txdesc;
err_out:
sdmac->status = DMA_ERROR;
return NULL;
@@ -1326,6 +1351,7 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
int num_periods = buf_len / period_len;
int channel = sdmac->channel;
int ret, i = 0, buf = 0;
+ struct sdma_desc *desc = sdmac->desc;
dev_dbg(sdma->dev, "%s channel: %d\n", __func__, channel);
@@ -1334,10 +1360,10 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
sdmac->status = DMA_IN_PROGRESS;
- sdmac->buf_tail = 0;
- sdmac->buf_ptail = 0;
- sdmac->chn_real_count = 0;
- sdmac->period_len = period_len;
+ desc->buf_tail = 0;
+ desc->buf_ptail = 0;
+ desc->chn_real_count = 0;
+ desc->period_len = period_len;
sdmac->flags |= IMX_DMA_SG_LOOP;
sdmac->direction = direction;
@@ -1358,7 +1384,7 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
}
while (buf < buf_len) {
- struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
+ struct sdma_buffer_descriptor *bd = &desc->bd[i];
int param;
bd->buffer_addr = dma_addr;
@@ -1389,10 +1415,10 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
i++;
}
- sdmac->num_bd = num_periods;
- sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
+ desc->num_bd = num_periods;
+ sdma->channel_control[channel].current_bd_ptr = desc->bd_phys;
- return &sdmac->desc;
+ return &sdmac->txdesc;
err_out:
sdmac->status = DMA_ERROR;
return NULL;
@@ -1431,13 +1457,14 @@ static enum dma_status sdma_tx_status(struct dma_chan *chan,
struct dma_tx_state *txstate)
{
struct sdma_channel *sdmac = to_sdma_chan(chan);
+ struct sdma_desc *desc = sdmac->desc;
u32 residue;
if (sdmac->flags & IMX_DMA_SG_LOOP)
- residue = (sdmac->num_bd - sdmac->buf_ptail) *
- sdmac->period_len - sdmac->chn_real_count;
+ residue = (desc->num_bd - desc->buf_ptail) *
+ desc->period_len - desc->chn_real_count;
else
- residue = sdmac->chn_count - sdmac->chn_real_count;
+ residue = desc->chn_count - desc->chn_real_count;
dma_set_tx_state(txstate, chan->completed_cookie, chan->cookie,
residue);
@@ -1661,6 +1688,8 @@ static int sdma_init(struct sdma_engine *sdma)
if (ret)
goto err_dma_alloc;
+ sdma->bd0 = sdma->channel[0].desc->bd;
+
sdma_config_ownership(&sdma->channel[0], false, true, false);
/* Set Command Channel (Channel Zero) */
--
2.17.1
--
Pengutronix e.K. | |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
^ permalink raw reply related [flat|nested] 9+ messages in thread* RE: [PATCH v2 0/5] add virt-dma support for imx-sdma
2018-06-08 8:43 ` Sascha Hauer
@ 2018-06-08 9:43 ` Robin Gong
0 siblings, 0 replies; 9+ messages in thread
From: Robin Gong @ 2018-06-08 9:43 UTC (permalink / raw)
To: Sascha Hauer
Cc: vkoul, dan.j.williams, dmaengine, linux-kernel, linux-arm-kernel,
dl-linux-imx
Thanks Sacha, I'll intergrate it into v3.
-----Original Message-----
From: Sascha Hauer [mailto:s.hauer@pengutronix.de]
Sent: 2018年6月8日 16:43
To: Robin Gong <yibin.gong@nxp.com>
Cc: vkoul@kernel.org; dan.j.williams@intel.com; dmaengine@vger.kernel.org; linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org; dl-linux-imx <linux-imx@nxp.com>
Subject: Re: [PATCH v2 0/5] add virt-dma support for imx-sdma
On Fri, Jun 08, 2018 at 09:44:45PM +0800, Robin Gong wrote:
> The legacy sdma driver has below limitations or drawbacks:
> 1. Hardcode the max BDs number as "PAGE_SIZE / sizeof(*)", and alloc
> one page size for one channel regardless of only few BDs needed
> most time. But in few cases, the max PAGE_SIZE maybe not enough.
> 2. One SDMA channel can't stop immediatley once channel disabled which
> means SDMA interrupt may come in after this channel terminated.There
> are some patches for this corner case such as commit "2746e2c389f9",
> but not cover non-cyclic.
>
> The common virt-dma overcomes the above limitations. It can alloc bd
> dynamically and free bd once this tx transfer done. No memory wasted
> or maximum limititation here, only depends on how many memory can be
> requested from kernel. For No.2, such issue can be workaround by
> checking if there is available descript("sdmac->desc") now once the
> unwanted interrupt coming. At last the common virt-dma is easier for sdma driver maintain.
>
> Change from v1:
> 1. split v1 patch into 5 patches.
> 2. remove some unnecessary condition check.
> 3. remove unneccessary 'pending' list.
>
> Robin Gong (5):
> dmaengine: imx-sdma: add virt-dma support
> Revert "dmaengine: imx-sdma: fix pagefault when channel is disabled
> during interrupt"
> dmaengine: imx-sdma: remove usless lock
> dmaengine: imx-sdma: remove the maximum limation for bd numbers
> dmaengine: imx-sdma: add sdma_transfer_init to decrease code overlap
>
> drivers/dma/Kconfig | 1 +
> drivers/dma/imx-sdma.c | 392
> ++++++++++++++++++++++++++++---------------------
> 2 files changed, 227 insertions(+), 166 deletions(-)
Please put the attached patch in front of your series. It makes the virt-dma support patch smaller and thus easier to review.
Sascha
--------------------------------8<----------------------------------
From a70ccdf780cc6fcddd2d06c4a3eb0123d4aba443 Mon Sep 17 00:00:00 2001
From: Sascha Hauer <s.hauer@pengutronix.de>
Date: Fri, 8 Jun 2018 10:20:18 +0200
Subject: [PATCH 1/2] dmaengine: imx-sdma: factor out a struct sdma_desc from struct sdma_channel
This is a preparation step to make the adding of virt-dma easier.
We create a struct sdma_desc, move some fields from struct sdma_channel there and add a pointer from the former to the latter. For now we allocate the data statically in struct sdma_channel, but with virt-dma support it will be dynamically allocated.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
drivers/dma/imx-sdma.c | 137 +++++++++++++++++++++++++----------------
1 file changed, 83 insertions(+), 54 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c index ccd03c3cedfe..556d08712f4a 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -295,6 +295,30 @@ struct sdma_context_data {
struct sdma_engine;
+/**
+ * struct sdma_desc - descriptor structor for one transfer
+ * @vd descriptor for virt dma
+ * @num_bd max NUM_BD. number of descriptors currently handling
+ * @buf_tail ID of the buffer that was processed
+ * @buf_ptail ID of the previous buffer that was processed
+ * @period_len period length, used in cyclic.
+ * @chn_real_count the real count updated from bd->mode.count
+ * @chn_count the transfer count setuped
+ * @sdmac sdma_channel pointer
+ * @bd pointer of alloced bd
+ */
+struct sdma_desc {
+ unsigned int num_bd;
+ dma_addr_t bd_phys;
+ unsigned int buf_tail;
+ unsigned int buf_ptail;
+ unsigned int period_len;
+ unsigned int chn_real_count;
+ unsigned int chn_count;
+ struct sdma_channel *sdmac;
+ struct sdma_buffer_descriptor *bd;
+};
+
/**
* struct sdma_channel - housekeeping for a SDMA channel
*
@@ -305,11 +329,10 @@ struct sdma_engine;
* @event_id0 aka dma request line
* @event_id1 for channels that use 2 events
* @word_size peripheral access size
- * @buf_tail ID of the buffer that was processed
- * @buf_ptail ID of the previous buffer that was processed
- * @num_bd max NUM_BD. number of descriptors currently handling
*/
struct sdma_channel {
+ struct sdma_desc *desc;
+ struct sdma_desc _desc;
struct sdma_engine *sdma;
unsigned int channel;
enum dma_transfer_direction direction;
@@ -317,12 +340,6 @@ struct sdma_channel {
unsigned int event_id0;
unsigned int event_id1;
enum dma_slave_buswidth word_size;
- unsigned int buf_tail;
- unsigned int buf_ptail;
- unsigned int num_bd;
- unsigned int period_len;
- struct sdma_buffer_descriptor *bd;
- dma_addr_t bd_phys;
unsigned int pc_from_device, pc_to_device;
unsigned int device_to_device;
unsigned long flags;
@@ -332,10 +349,8 @@ struct sdma_channel {
u32 shp_addr, per_addr;
struct dma_chan chan;
spinlock_t lock;
- struct dma_async_tx_descriptor desc;
+ struct dma_async_tx_descriptor txdesc;
enum dma_status status;
- unsigned int chn_count;
- unsigned int chn_real_count;
struct tasklet_struct tasklet;
struct imx_dma_data data;
bool enabled;
@@ -398,6 +413,8 @@ struct sdma_engine {
u32 spba_start_addr;
u32 spba_end_addr;
unsigned int irq;
+ dma_addr_t bd0_phys;
+ struct sdma_buffer_descriptor *bd0;
};
static struct sdma_driver_data sdma_imx31 = { @@ -632,7 +649,7 @@ static int sdma_run_channel0(struct sdma_engine *sdma) static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size,
u32 address)
{
- struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
+ struct sdma_buffer_descriptor *bd0 = sdma->bd0;
void *buf_virt;
dma_addr_t buf_phys;
int ret;
@@ -707,7 +724,9 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
* call callback function.
*/
while (1) {
- bd = &sdmac->bd[sdmac->buf_tail];
+ struct sdma_desc *desc = sdmac->desc;
+
+ bd = &desc->bd[desc->buf_tail];
if (bd->mode.status & BD_DONE)
break;
@@ -723,11 +742,11 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
* the number of bytes present in the current buffer descriptor.
*/
- sdmac->chn_real_count = bd->mode.count;
+ desc->chn_real_count = bd->mode.count;
bd->mode.status |= BD_DONE;
- bd->mode.count = sdmac->period_len;
- sdmac->buf_ptail = sdmac->buf_tail;
- sdmac->buf_tail = (sdmac->buf_tail + 1) % sdmac->num_bd;
+ bd->mode.count = desc->period_len;
+ desc->buf_ptail = desc->buf_tail;
+ desc->buf_tail = (desc->buf_tail + 1) % desc->num_bd;
/*
* The callback is called from the interrupt context in order @@ -736,7 +755,7 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
* executed.
*/
- dmaengine_desc_get_callback_invoke(&sdmac->desc, NULL);
+ dmaengine_desc_get_callback_invoke(&sdmac->txdesc, NULL);
if (error)
sdmac->status = old_status;
@@ -749,17 +768,17 @@ static void mxc_sdma_handle_channel_normal(unsigned long data)
struct sdma_buffer_descriptor *bd;
int i, error = 0;
- sdmac->chn_real_count = 0;
+ sdmac->desc->chn_real_count = 0;
/*
* non loop mode. Iterate over all descriptors, collect
* errors and call callback function
*/
- for (i = 0; i < sdmac->num_bd; i++) {
- bd = &sdmac->bd[i];
+ for (i = 0; i < sdmac->desc->num_bd; i++) {
+ bd = &sdmac->desc->bd[i];
if (bd->mode.status & (BD_DONE | BD_RROR))
error = -EIO;
- sdmac->chn_real_count += bd->mode.count;
+ sdmac->desc->chn_real_count += bd->mode.count;
}
if (error)
@@ -767,9 +786,9 @@ static void mxc_sdma_handle_channel_normal(unsigned long data)
else
sdmac->status = DMA_COMPLETE;
- dma_cookie_complete(&sdmac->desc);
+ dma_cookie_complete(&sdmac->txdesc);
- dmaengine_desc_get_callback_invoke(&sdmac->desc, NULL);
+ dmaengine_desc_get_callback_invoke(&sdmac->txdesc, NULL);
}
static irqreturn_t sdma_int_handler(int irq, void *dev_id) @@ -897,7 +916,7 @@ static int sdma_load_context(struct sdma_channel *sdmac)
int channel = sdmac->channel;
int load_address;
struct sdma_context_data *context = sdma->context;
- struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
+ struct sdma_buffer_descriptor *bd0 = sdma->bd0;
int ret;
unsigned long flags;
@@ -1100,18 +1119,22 @@ static int sdma_set_channel_priority(struct sdma_channel *sdmac, static int sdma_request_channel(struct sdma_channel *sdmac) {
struct sdma_engine *sdma = sdmac->sdma;
+ struct sdma_desc *desc;
int channel = sdmac->channel;
int ret = -EBUSY;
- sdmac->bd = dma_zalloc_coherent(NULL, PAGE_SIZE, &sdmac->bd_phys,
+ sdmac->desc = &sdmac->_desc;
+ desc = sdmac->desc;
+
+ desc->bd = dma_zalloc_coherent(NULL, PAGE_SIZE, &desc->bd_phys,
GFP_KERNEL);
- if (!sdmac->bd) {
+ if (!desc->bd) {
ret = -ENOMEM;
goto out;
}
- sdma->channel_control[channel].base_bd_ptr = sdmac->bd_phys;
- sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
+ sdma->channel_control[channel].base_bd_ptr = desc->bd_phys;
+ sdma->channel_control[channel].current_bd_ptr = desc->bd_phys;
sdma_set_channel_priority(sdmac, MXC_SDMA_DEFAULT_PRIORITY);
return 0;
@@ -1176,10 +1199,10 @@ static int sdma_alloc_chan_resources(struct dma_chan *chan)
if (ret)
goto disable_clk_ahb;
- dma_async_tx_descriptor_init(&sdmac->desc, chan);
- sdmac->desc.tx_submit = sdma_tx_submit;
+ dma_async_tx_descriptor_init(&sdmac->txdesc, chan);
+ sdmac->txdesc.tx_submit = sdma_tx_submit;
/* txd.flags will be overwritten in prep funcs */
- sdmac->desc.flags = DMA_CTRL_ACK;
+ sdmac->txdesc.flags = DMA_CTRL_ACK;
return 0;
@@ -1194,6 +1217,7 @@ static void sdma_free_chan_resources(struct dma_chan *chan) {
struct sdma_channel *sdmac = to_sdma_chan(chan);
struct sdma_engine *sdma = sdmac->sdma;
+ struct sdma_desc *desc = sdmac->desc;
sdma_disable_channel(chan);
@@ -1207,7 +1231,7 @@ static void sdma_free_chan_resources(struct dma_chan *chan)
sdma_set_channel_priority(sdmac, 0);
- dma_free_coherent(NULL, PAGE_SIZE, sdmac->bd, sdmac->bd_phys);
+ dma_free_coherent(NULL, PAGE_SIZE, desc->bd, desc->bd_phys);
clk_disable(sdma->clk_ipg);
clk_disable(sdma->clk_ahb);
@@ -1223,6 +1247,7 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
int ret, i, count;
int channel = sdmac->channel;
struct scatterlist *sg;
+ struct sdma_desc *desc = sdmac->desc;
if (sdmac->status == DMA_IN_PROGRESS)
return NULL;
@@ -1230,9 +1255,9 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
sdmac->flags = 0;
- sdmac->buf_tail = 0;
- sdmac->buf_ptail = 0;
- sdmac->chn_real_count = 0;
+ desc->buf_tail = 0;
+ desc->buf_ptail = 0;
+ desc->chn_real_count = 0;
dev_dbg(sdma->dev, "setting up %d entries for channel %d.\n",
sg_len, channel);
@@ -1249,9 +1274,9 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
goto err_out;
}
- sdmac->chn_count = 0;
+ desc->chn_count = 0;
for_each_sg(sgl, sg, sg_len, i) {
- struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
+ struct sdma_buffer_descriptor *bd = &desc->bd[i];
int param;
bd->buffer_addr = sg->dma_address;
@@ -1266,7 +1291,7 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
}
bd->mode.count = count;
- sdmac->chn_count += count;
+ desc->chn_count += count;
if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES) {
ret = -EINVAL;
@@ -1307,10 +1332,10 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
bd->mode.status = param;
}
- sdmac->num_bd = sg_len;
- sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
+ desc->num_bd = sg_len;
+ sdma->channel_control[channel].current_bd_ptr = desc->bd_phys;
- return &sdmac->desc;
+ return &sdmac->txdesc;
err_out:
sdmac->status = DMA_ERROR;
return NULL;
@@ -1326,6 +1351,7 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
int num_periods = buf_len / period_len;
int channel = sdmac->channel;
int ret, i = 0, buf = 0;
+ struct sdma_desc *desc = sdmac->desc;
dev_dbg(sdma->dev, "%s channel: %d\n", __func__, channel);
@@ -1334,10 +1360,10 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
sdmac->status = DMA_IN_PROGRESS;
- sdmac->buf_tail = 0;
- sdmac->buf_ptail = 0;
- sdmac->chn_real_count = 0;
- sdmac->period_len = period_len;
+ desc->buf_tail = 0;
+ desc->buf_ptail = 0;
+ desc->chn_real_count = 0;
+ desc->period_len = period_len;
sdmac->flags |= IMX_DMA_SG_LOOP;
sdmac->direction = direction;
@@ -1358,7 +1384,7 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
}
while (buf < buf_len) {
- struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
+ struct sdma_buffer_descriptor *bd = &desc->bd[i];
int param;
bd->buffer_addr = dma_addr;
@@ -1389,10 +1415,10 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
i++;
}
- sdmac->num_bd = num_periods;
- sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
+ desc->num_bd = num_periods;
+ sdma->channel_control[channel].current_bd_ptr = desc->bd_phys;
- return &sdmac->desc;
+ return &sdmac->txdesc;
err_out:
sdmac->status = DMA_ERROR;
return NULL;
@@ -1431,13 +1457,14 @@ static enum dma_status sdma_tx_status(struct dma_chan *chan,
struct dma_tx_state *txstate) {
struct sdma_channel *sdmac = to_sdma_chan(chan);
+ struct sdma_desc *desc = sdmac->desc;
u32 residue;
if (sdmac->flags & IMX_DMA_SG_LOOP)
- residue = (sdmac->num_bd - sdmac->buf_ptail) *
- sdmac->period_len - sdmac->chn_real_count;
+ residue = (desc->num_bd - desc->buf_ptail) *
+ desc->period_len - desc->chn_real_count;
else
- residue = sdmac->chn_count - sdmac->chn_real_count;
+ residue = desc->chn_count - desc->chn_real_count;
dma_set_tx_state(txstate, chan->completed_cookie, chan->cookie,
residue);
@@ -1661,6 +1688,8 @@ static int sdma_init(struct sdma_engine *sdma)
if (ret)
goto err_dma_alloc;
+ sdma->bd0 = sdma->channel[0].desc->bd;
+
sdma_config_ownership(&sdma->channel[0], false, true, false);
/* Set Command Channel (Channel Zero) */
--
2.17.1
--
Pengutronix e.K. | |
Industrial Linux Solutions | https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.pengutronix.de%2F&data=02%7C01%7Cyibin.gong%40nxp.com%7Cf4671adfeaa947506e2b08d5cd1be23d%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C636640442016947893&sdata=6FkizxBudOfDkWUrj28qYaycOz%2Br0bwf7DJJ8vZgaKg%3D&reserved=0 |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v2 1/5] dmaengine: imx-sdma: add virt-dma support
2018-06-08 13:44 [PATCH v2 0/5] add virt-dma support for imx-sdma Robin Gong
2018-06-08 8:43 ` Sascha Hauer
@ 2018-06-08 13:44 ` Robin Gong
2018-06-08 8:43 ` Sascha Hauer
2018-06-08 13:44 ` [PATCH v2 2/5] Revert "dmaengine: imx-sdma: fix pagefault when channel is disabled during interrupt" Robin Gong
` (3 subsequent siblings)
5 siblings, 1 reply; 9+ messages in thread
From: Robin Gong @ 2018-06-08 13:44 UTC (permalink / raw)
To: vkoul, s.hauer, dan.j.williams
Cc: dmaengine, linux-kernel, linux-arm-kernel, linux-imx
The legacy sdma driver has below limitations or drawbacks:
1. Hardcode the max BDs number as "PAGE_SIZE / sizeof(*)", and alloc
one page size for one channel regardless of only few BDs needed
most time. But in few cases, the max PAGE_SIZE maybe not enough.
2. One SDMA channel can't stop immediatley once channel disabled which
means SDMA interrupt may come in after this channel terminated.There
are some patches for this corner case such as commit "2746e2c389f9",
but not cover non-cyclic.
The common virt-dma overcomes the above limitations. It can alloc bd
dynamically and free bd once this tx transfer done. No memory wasted or
maximum limititation here, only depends on how many memory can be requested
from kernel. For No.2, such issue can be workaround by checking if there
is available descript("sdmac->desc") now once the unwanted interrupt
coming. At last the common virt-dma is easier for sdma driver maintain.
The main changes as below:
--new "sdma_desc" structure containing virt_dma_desc and some members
which moved from "sdma_channel" such as "num_bd","bd_phys","bd",etc,
since multi descriptors may exist on virtual dma framework
rather than only one as before.
--remove some members of "sdma_channel" structure since it's handled
by virtual dma common framework, such as "tasklet", "dma_chan",etc.
--add specific BD0 for channel0 since such bd descriptor is must and
basic for other dma channel, no need alloc/free as other channel,so
request it during probe.
--remove sdma_request_channel(),sdma_tx_submit(),etc.
--alloc/free bd descriptor added and code changes for virtual dma.
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
---
drivers/dma/Kconfig | 1 +
drivers/dma/imx-sdma.c | 332 ++++++++++++++++++++++++++++++++-----------------
2 files changed, 220 insertions(+), 113 deletions(-)
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index ca1680a..d4a4230 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -250,6 +250,7 @@ config IMX_SDMA
tristate "i.MX SDMA support"
depends on ARCH_MXC
select DMA_ENGINE
+ select DMA_VIRTUAL_CHANNELS
help
Support the i.MX SDMA engine. This engine is integrated into
Freescale i.MX25/31/35/51/53/6 chips.
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index ccd03c3..8d0c1fd 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -48,6 +48,7 @@
#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
#include "dmaengine.h"
+#include "virt-dma.h"
/* SDMA registers */
#define SDMA_H_C0PTR 0x000
@@ -296,6 +297,31 @@ struct sdma_context_data {
struct sdma_engine;
/**
+ * struct sdma_desc - descriptor structor for one transfer
+ * @vd descriptor for virt dma
+ * @num_bd max NUM_BD. number of descriptors currently handling
+ * @buf_tail ID of the buffer that was processed
+ * @buf_ptail ID of the previous buffer that was processed
+ * @period_len period length, used in cyclic.
+ * @chn_real_count the real count updated from bd->mode.count
+ * @chn_count the transfer count setuped
+ * @sdmac sdma_channel pointer
+ * @bd pointer of alloced bd
+ */
+struct sdma_desc {
+ struct virt_dma_desc vd;
+ unsigned int num_bd;
+ dma_addr_t bd_phys;
+ unsigned int buf_tail;
+ unsigned int buf_ptail;
+ unsigned int period_len;
+ unsigned int chn_real_count;
+ unsigned int chn_count;
+ struct sdma_channel *sdmac;
+ struct sdma_buffer_descriptor *bd;
+};
+
+/**
* struct sdma_channel - housekeeping for a SDMA channel
*
* @sdma pointer to the SDMA engine for this channel
@@ -305,11 +331,10 @@ struct sdma_engine;
* @event_id0 aka dma request line
* @event_id1 for channels that use 2 events
* @word_size peripheral access size
- * @buf_tail ID of the buffer that was processed
- * @buf_ptail ID of the previous buffer that was processed
- * @num_bd max NUM_BD. number of descriptors currently handling
*/
struct sdma_channel {
+ struct virt_dma_chan vc;
+ struct sdma_desc *desc;
struct sdma_engine *sdma;
unsigned int channel;
enum dma_transfer_direction direction;
@@ -317,12 +342,6 @@ struct sdma_channel {
unsigned int event_id0;
unsigned int event_id1;
enum dma_slave_buswidth word_size;
- unsigned int buf_tail;
- unsigned int buf_ptail;
- unsigned int num_bd;
- unsigned int period_len;
- struct sdma_buffer_descriptor *bd;
- dma_addr_t bd_phys;
unsigned int pc_from_device, pc_to_device;
unsigned int device_to_device;
unsigned long flags;
@@ -330,13 +349,10 @@ struct sdma_channel {
unsigned long event_mask[2];
unsigned long watermark_level;
u32 shp_addr, per_addr;
- struct dma_chan chan;
spinlock_t lock;
- struct dma_async_tx_descriptor desc;
enum dma_status status;
unsigned int chn_count;
unsigned int chn_real_count;
- struct tasklet_struct tasklet;
struct imx_dma_data data;
bool enabled;
};
@@ -398,6 +414,8 @@ struct sdma_engine {
u32 spba_start_addr;
u32 spba_end_addr;
unsigned int irq;
+ dma_addr_t bd0_phys;
+ struct sdma_buffer_descriptor *bd0;
};
static struct sdma_driver_data sdma_imx31 = {
@@ -632,7 +650,7 @@ static int sdma_run_channel0(struct sdma_engine *sdma)
static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size,
u32 address)
{
- struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
+ struct sdma_buffer_descriptor *bd0 = sdma->bd0;
void *buf_virt;
dma_addr_t buf_phys;
int ret;
@@ -688,6 +706,35 @@ static void sdma_event_disable(struct sdma_channel *sdmac, unsigned int event)
writel_relaxed(val, sdma->regs + chnenbl);
}
+static struct sdma_desc *to_sdma_desc(struct dma_async_tx_descriptor *t)
+{
+ return container_of(t, struct sdma_desc, vd.tx);
+}
+
+static void sdma_start_desc(struct sdma_channel *sdmac)
+{
+ struct virt_dma_desc *vd = vchan_next_desc(&sdmac->vc);
+ struct sdma_desc *desc;
+ struct sdma_engine *sdma = sdmac->sdma;
+ int channel = sdmac->channel;
+
+ if (!vd) {
+ sdmac->desc = NULL;
+ return;
+ }
+ sdmac->desc = desc = to_sdma_desc(&vd->tx);
+ /*
+ * Do not delete the node in desc_issued list in cyclic mode, otherwise
+ * the desc alloced will never be freed in vchan_dma_desc_free_list
+ */
+ if (!(sdmac->flags & IMX_DMA_SG_LOOP))
+ list_del(&vd->node);
+
+ sdma->channel_control[channel].base_bd_ptr = desc->bd_phys;
+ sdma->channel_control[channel].current_bd_ptr = desc->bd_phys;
+ sdma_enable_channel(sdma, sdmac->channel);
+}
+
static void sdma_update_channel_loop(struct sdma_channel *sdmac)
{
struct sdma_buffer_descriptor *bd;
@@ -706,8 +753,10 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
* loop mode. Iterate over descriptors, re-setup them and
* call callback function.
*/
- while (1) {
- bd = &sdmac->bd[sdmac->buf_tail];
+ while (sdmac->desc) {
+ struct sdma_desc *desc = sdmac->desc;
+
+ bd = &desc->bd[desc->buf_tail];
if (bd->mode.status & BD_DONE)
break;
@@ -723,11 +772,11 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
* the number of bytes present in the current buffer descriptor.
*/
- sdmac->chn_real_count = bd->mode.count;
+ desc->chn_real_count = bd->mode.count;
bd->mode.status |= BD_DONE;
- bd->mode.count = sdmac->period_len;
- sdmac->buf_ptail = sdmac->buf_tail;
- sdmac->buf_tail = (sdmac->buf_tail + 1) % sdmac->num_bd;
+ bd->mode.count = desc->period_len;
+ desc->buf_ptail = desc->buf_tail;
+ desc->buf_tail = (desc->buf_tail + 1) % desc->num_bd;
/*
* The callback is called from the interrupt context in order
@@ -736,40 +785,36 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
* executed.
*/
- dmaengine_desc_get_callback_invoke(&sdmac->desc, NULL);
+ dmaengine_desc_get_callback_invoke(&desc->vd.tx, NULL);
if (error)
sdmac->status = old_status;
}
}
-static void mxc_sdma_handle_channel_normal(unsigned long data)
+static void mxc_sdma_handle_channel_normal(struct sdma_channel *data)
{
struct sdma_channel *sdmac = (struct sdma_channel *) data;
struct sdma_buffer_descriptor *bd;
int i, error = 0;
- sdmac->chn_real_count = 0;
+ sdmac->desc->chn_real_count = 0;
/*
* non loop mode. Iterate over all descriptors, collect
* errors and call callback function
*/
- for (i = 0; i < sdmac->num_bd; i++) {
- bd = &sdmac->bd[i];
+ for (i = 0; i < sdmac->desc->num_bd; i++) {
+ bd = &sdmac->desc->bd[i];
if (bd->mode.status & (BD_DONE | BD_RROR))
error = -EIO;
- sdmac->chn_real_count += bd->mode.count;
+ sdmac->desc->chn_real_count += bd->mode.count;
}
if (error)
sdmac->status = DMA_ERROR;
else
sdmac->status = DMA_COMPLETE;
-
- dma_cookie_complete(&sdmac->desc);
-
- dmaengine_desc_get_callback_invoke(&sdmac->desc, NULL);
}
static irqreturn_t sdma_int_handler(int irq, void *dev_id)
@@ -785,13 +830,22 @@ static irqreturn_t sdma_int_handler(int irq, void *dev_id)
while (stat) {
int channel = fls(stat) - 1;
struct sdma_channel *sdmac = &sdma->channel[channel];
-
- if (sdmac->flags & IMX_DMA_SG_LOOP)
- sdma_update_channel_loop(sdmac);
- else
- tasklet_schedule(&sdmac->tasklet);
+ struct sdma_desc *desc;
+
+ spin_lock(&sdmac->vc.lock);
+ desc = sdmac->desc;
+ if (desc) {
+ if (sdmac->flags & IMX_DMA_SG_LOOP) {
+ sdma_update_channel_loop(sdmac);
+ } else {
+ mxc_sdma_handle_channel_normal(sdmac);
+ vchan_cookie_complete(&desc->vd);
+ sdma_start_desc(sdmac);
+ }
+ }
__clear_bit(channel, &stat);
+ spin_unlock(&sdmac->vc.lock);
}
return IRQ_HANDLED;
@@ -897,7 +951,7 @@ static int sdma_load_context(struct sdma_channel *sdmac)
int channel = sdmac->channel;
int load_address;
struct sdma_context_data *context = sdma->context;
- struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
+ struct sdma_buffer_descriptor *bd0 = sdma->bd0;
int ret;
unsigned long flags;
@@ -946,7 +1000,7 @@ static int sdma_load_context(struct sdma_channel *sdmac)
static struct sdma_channel *to_sdma_chan(struct dma_chan *chan)
{
- return container_of(chan, struct sdma_channel, chan);
+ return container_of(chan, struct sdma_channel, vc.chan);
}
static int sdma_disable_channel(struct dma_chan *chan)
@@ -968,7 +1022,16 @@ static int sdma_disable_channel(struct dma_chan *chan)
static int sdma_disable_channel_with_delay(struct dma_chan *chan)
{
+ struct sdma_channel *sdmac = to_sdma_chan(chan);
+ unsigned long flags;
+ LIST_HEAD(head);
+
sdma_disable_channel(chan);
+ spin_lock_irqsave(&sdmac->vc.lock, flags);
+ vchan_get_all_descriptors(&sdmac->vc, &head);
+ sdmac->desc = NULL;
+ spin_unlock_irqrestore(&sdmac->vc.lock, flags);
+ vchan_dma_desc_free_list(&sdmac->vc, &head);
/*
* According to NXP R&D team a delay of one BD SDMA cost time
@@ -1097,42 +1160,55 @@ static int sdma_set_channel_priority(struct sdma_channel *sdmac,
return 0;
}
-static int sdma_request_channel(struct sdma_channel *sdmac)
+static int sdma_request_channel0(struct sdma_engine *sdma)
{
- struct sdma_engine *sdma = sdmac->sdma;
- int channel = sdmac->channel;
- int ret = -EBUSY;
+ int ret = 0;
- sdmac->bd = dma_zalloc_coherent(NULL, PAGE_SIZE, &sdmac->bd_phys,
+ sdma->bd0 = dma_zalloc_coherent(NULL, PAGE_SIZE, &sdma->bd0_phys,
GFP_KERNEL);
- if (!sdmac->bd) {
+ if (!sdma->bd0) {
ret = -ENOMEM;
goto out;
}
- sdma->channel_control[channel].base_bd_ptr = sdmac->bd_phys;
- sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
+ sdma->channel_control[0].base_bd_ptr = sdma->bd0_phys;
+ sdma->channel_control[0].current_bd_ptr = sdma->bd0_phys;
- sdma_set_channel_priority(sdmac, MXC_SDMA_DEFAULT_PRIORITY);
+ sdma_set_channel_priority(&sdma->channel[0], MXC_SDMA_DEFAULT_PRIORITY);
return 0;
out:
-
return ret;
}
-static dma_cookie_t sdma_tx_submit(struct dma_async_tx_descriptor *tx)
+static int sdma_alloc_bd(struct sdma_desc *desc)
{
- unsigned long flags;
- struct sdma_channel *sdmac = to_sdma_chan(tx->chan);
- dma_cookie_t cookie;
+ u32 bd_size = desc->num_bd * sizeof(struct sdma_buffer_descriptor);
+ int ret = 0;
- spin_lock_irqsave(&sdmac->lock, flags);
+ desc->bd = dma_zalloc_coherent(NULL, bd_size, &desc->bd_phys,
+ GFP_KERNEL);
+ if (!desc->bd) {
+ ret = -ENOMEM;
+ goto out;
+ }
+out:
+
+ return ret;
+}
- cookie = dma_cookie_assign(tx);
+static void sdma_free_bd(struct sdma_desc *desc)
+{
+ u32 bd_size = desc->num_bd * sizeof(struct sdma_buffer_descriptor);
- spin_unlock_irqrestore(&sdmac->lock, flags);
+ dma_free_coherent(NULL, bd_size, desc->bd, desc->bd_phys);
+}
+
+static void sdma_desc_free(struct virt_dma_desc *vd)
+{
+ struct sdma_desc *desc = container_of(vd, struct sdma_desc, vd);
- return cookie;
+ sdma_free_bd(desc);
+ kfree(desc);
}
static int sdma_alloc_chan_resources(struct dma_chan *chan)
@@ -1168,19 +1244,10 @@ static int sdma_alloc_chan_resources(struct dma_chan *chan)
if (ret)
goto disable_clk_ipg;
- ret = sdma_request_channel(sdmac);
- if (ret)
- goto disable_clk_ahb;
-
ret = sdma_set_channel_priority(sdmac, prio);
if (ret)
goto disable_clk_ahb;
- dma_async_tx_descriptor_init(&sdmac->desc, chan);
- sdmac->desc.tx_submit = sdma_tx_submit;
- /* txd.flags will be overwritten in prep funcs */
- sdmac->desc.flags = DMA_CTRL_ACK;
-
return 0;
disable_clk_ahb:
@@ -1195,7 +1262,7 @@ static void sdma_free_chan_resources(struct dma_chan *chan)
struct sdma_channel *sdmac = to_sdma_chan(chan);
struct sdma_engine *sdma = sdmac->sdma;
- sdma_disable_channel(chan);
+ sdma_disable_channel_with_delay(chan);
if (sdmac->event_id0)
sdma_event_disable(sdmac, sdmac->event_id0);
@@ -1207,8 +1274,6 @@ static void sdma_free_chan_resources(struct dma_chan *chan)
sdma_set_channel_priority(sdmac, 0);
- dma_free_coherent(NULL, PAGE_SIZE, sdmac->bd, sdmac->bd_phys);
-
clk_disable(sdma->clk_ipg);
clk_disable(sdma->clk_ahb);
}
@@ -1223,6 +1288,7 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
int ret, i, count;
int channel = sdmac->channel;
struct scatterlist *sg;
+ struct sdma_desc *desc;
if (sdmac->status == DMA_IN_PROGRESS)
return NULL;
@@ -1230,9 +1296,20 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
sdmac->flags = 0;
- sdmac->buf_tail = 0;
- sdmac->buf_ptail = 0;
- sdmac->chn_real_count = 0;
+ desc = kzalloc((sizeof(*desc)), GFP_KERNEL);
+ if (!desc)
+ goto err_out;
+
+ desc->buf_tail = 0;
+ desc->buf_ptail = 0;
+ desc->sdmac = sdmac;
+ desc->num_bd = sg_len;
+ desc->chn_real_count = 0;
+
+ if (sdma_alloc_bd(desc)) {
+ kfree(desc);
+ goto err_out;
+ }
dev_dbg(sdma->dev, "setting up %d entries for channel %d.\n",
sg_len, channel);
@@ -1240,18 +1317,18 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
sdmac->direction = direction;
ret = sdma_load_context(sdmac);
if (ret)
- goto err_out;
+ goto err_bd_out;
if (sg_len > NUM_BD) {
dev_err(sdma->dev, "SDMA channel %d: maximum number of sg exceeded: %d > %d\n",
channel, sg_len, NUM_BD);
ret = -EINVAL;
- goto err_out;
+ goto err_bd_out;
}
- sdmac->chn_count = 0;
+ desc->chn_count = 0;
for_each_sg(sgl, sg, sg_len, i) {
- struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
+ struct sdma_buffer_descriptor *bd = &desc->bd[i];
int param;
bd->buffer_addr = sg->dma_address;
@@ -1262,33 +1339,33 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
dev_err(sdma->dev, "SDMA channel %d: maximum bytes for sg entry exceeded: %d > %d\n",
channel, count, 0xffff);
ret = -EINVAL;
- goto err_out;
+ goto err_bd_out;
}
bd->mode.count = count;
- sdmac->chn_count += count;
+ desc->chn_count += count;
if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES) {
ret = -EINVAL;
- goto err_out;
+ goto err_bd_out;
}
switch (sdmac->word_size) {
case DMA_SLAVE_BUSWIDTH_4_BYTES:
bd->mode.command = 0;
if (count & 3 || sg->dma_address & 3)
- return NULL;
+ goto err_bd_out;
break;
case DMA_SLAVE_BUSWIDTH_2_BYTES:
bd->mode.command = 2;
if (count & 1 || sg->dma_address & 1)
- return NULL;
+ goto err_bd_out;
break;
case DMA_SLAVE_BUSWIDTH_1_BYTE:
bd->mode.command = 1;
break;
default:
- return NULL;
+ goto err_bd_out;
}
param = BD_DONE | BD_EXTD | BD_CONT;
@@ -1307,10 +1384,10 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
bd->mode.status = param;
}
- sdmac->num_bd = sg_len;
- sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
-
- return &sdmac->desc;
+ return vchan_tx_prep(&sdmac->vc, &desc->vd, flags);
+err_bd_out:
+ sdma_free_bd(desc);
+ kfree(desc);
err_out:
sdmac->status = DMA_ERROR;
return NULL;
@@ -1326,6 +1403,7 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
int num_periods = buf_len / period_len;
int channel = sdmac->channel;
int ret, i = 0, buf = 0;
+ struct sdma_desc *desc;
dev_dbg(sdma->dev, "%s channel: %d\n", __func__, channel);
@@ -1334,31 +1412,43 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
sdmac->status = DMA_IN_PROGRESS;
- sdmac->buf_tail = 0;
- sdmac->buf_ptail = 0;
- sdmac->chn_real_count = 0;
- sdmac->period_len = period_len;
+ desc = kzalloc((sizeof(*desc)), GFP_KERNEL);
+ if (!desc)
+ goto err_out;
+
+ desc->buf_tail = 0;
+ desc->buf_ptail = 0;
+ desc->sdmac = sdmac;
+ desc->num_bd = num_periods;
+ desc->chn_real_count = 0;
+ desc->period_len = period_len;
sdmac->flags |= IMX_DMA_SG_LOOP;
sdmac->direction = direction;
+
+ if (sdma_alloc_bd(desc)) {
+ kfree(desc);
+ goto err_out;
+ }
+
ret = sdma_load_context(sdmac);
if (ret)
- goto err_out;
+ goto err_bd_out;
if (num_periods > NUM_BD) {
dev_err(sdma->dev, "SDMA channel %d: maximum number of sg exceeded: %d > %d\n",
channel, num_periods, NUM_BD);
- goto err_out;
+ goto err_bd_out;
}
if (period_len > 0xffff) {
dev_err(sdma->dev, "SDMA channel %d: maximum period size exceeded: %zu > %d\n",
channel, period_len, 0xffff);
- goto err_out;
+ goto err_bd_out;
}
while (buf < buf_len) {
- struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
+ struct sdma_buffer_descriptor *bd = &desc->bd[i];
int param;
bd->buffer_addr = dma_addr;
@@ -1366,7 +1456,7 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
bd->mode.count = period_len;
if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES)
- goto err_out;
+ goto err_bd_out;
if (sdmac->word_size == DMA_SLAVE_BUSWIDTH_4_BYTES)
bd->mode.command = 0;
else
@@ -1389,10 +1479,10 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
i++;
}
- sdmac->num_bd = num_periods;
- sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
-
- return &sdmac->desc;
+ return vchan_tx_prep(&sdmac->vc, &desc->vd, flags);
+err_bd_out:
+ sdma_free_bd(desc);
+ kfree(desc);
err_out:
sdmac->status = DMA_ERROR;
return NULL;
@@ -1432,12 +1522,30 @@ static enum dma_status sdma_tx_status(struct dma_chan *chan,
{
struct sdma_channel *sdmac = to_sdma_chan(chan);
u32 residue;
+ struct virt_dma_desc *vd;
+ struct sdma_desc *desc;
+ enum dma_status ret;
+ unsigned long flags;
- if (sdmac->flags & IMX_DMA_SG_LOOP)
- residue = (sdmac->num_bd - sdmac->buf_ptail) *
- sdmac->period_len - sdmac->chn_real_count;
- else
- residue = sdmac->chn_count - sdmac->chn_real_count;
+ ret = dma_cookie_status(chan, cookie, txstate);
+ if (ret == DMA_COMPLETE || !txstate)
+ return ret;
+
+ spin_lock_irqsave(&sdmac->vc.lock, flags);
+ vd = vchan_find_desc(&sdmac->vc, cookie);
+ if (vd) {
+ desc = to_sdma_desc(&vd->tx);
+ if (sdmac->flags & IMX_DMA_SG_LOOP)
+ residue = (desc->num_bd - desc->buf_ptail) *
+ desc->period_len - desc->chn_real_count;
+ else
+ residue = desc->chn_count - desc->chn_real_count;
+ } else if (sdmac->desc && sdmac->desc->vd.tx.cookie == cookie) {
+ residue = sdmac->desc->chn_count - sdmac->desc->chn_real_count;
+ } else {
+ residue = 0;
+ }
+ spin_unlock_irqrestore(&sdmac->vc.lock, flags);
dma_set_tx_state(txstate, chan->completed_cookie, chan->cookie,
residue);
@@ -1448,10 +1556,12 @@ static enum dma_status sdma_tx_status(struct dma_chan *chan,
static void sdma_issue_pending(struct dma_chan *chan)
{
struct sdma_channel *sdmac = to_sdma_chan(chan);
- struct sdma_engine *sdma = sdmac->sdma;
+ unsigned long flags;
- if (sdmac->status == DMA_IN_PROGRESS)
- sdma_enable_channel(sdma, sdmac->channel);
+ spin_lock_irqsave(&sdmac->vc.lock, flags);
+ if (vchan_issue_pending(&sdmac->vc) && !sdmac->desc)
+ sdma_start_desc(sdmac);
+ spin_unlock_irqrestore(&sdmac->vc.lock, flags);
}
#define SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V1 34
@@ -1657,7 +1767,7 @@ static int sdma_init(struct sdma_engine *sdma)
for (i = 0; i < MAX_DMA_CHANNELS; i++)
writel_relaxed(0, sdma->regs + SDMA_CHNPRI_0 + i * 4);
- ret = sdma_request_channel(&sdma->channel[0]);
+ ret = sdma_request_channel0(sdma);
if (ret)
goto err_dma_alloc;
@@ -1821,20 +1931,15 @@ static int sdma_probe(struct platform_device *pdev)
sdmac->sdma = sdma;
spin_lock_init(&sdmac->lock);
- sdmac->chan.device = &sdma->dma_device;
- dma_cookie_init(&sdmac->chan);
sdmac->channel = i;
-
- tasklet_init(&sdmac->tasklet, mxc_sdma_handle_channel_normal,
- (unsigned long) sdmac);
+ sdmac->vc.desc_free = sdma_desc_free;
/*
* Add the channel to the DMAC list. Do not add channel 0 though
* because we need it internally in the SDMA driver. This also means
* that channel 0 in dmaengine counting matches sdma channel 1.
*/
if (i)
- list_add_tail(&sdmac->chan.device_node,
- &sdma->dma_device.channels);
+ vchan_init(&sdmac->vc, &sdma->dma_device);
}
ret = sdma_init(sdma);
@@ -1939,7 +2044,8 @@ static int sdma_remove(struct platform_device *pdev)
for (i = 0; i < MAX_DMA_CHANNELS; i++) {
struct sdma_channel *sdmac = &sdma->channel[i];
- tasklet_kill(&sdmac->tasklet);
+ tasklet_kill(&sdmac->vc.task);
+ sdma_free_chan_resources(&sdmac->vc.chan);
}
platform_set_drvdata(pdev, NULL);
--
2.7.4
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [PATCH v2 1/5] dmaengine: imx-sdma: add virt-dma support
2018-06-08 13:44 ` [PATCH v2 1/5] dmaengine: imx-sdma: add virt-dma support Robin Gong
@ 2018-06-08 8:43 ` Sascha Hauer
0 siblings, 0 replies; 9+ messages in thread
From: Sascha Hauer @ 2018-06-08 8:43 UTC (permalink / raw)
To: Robin Gong
Cc: vkoul, dan.j.williams, dmaengine, linux-kernel, linux-arm-kernel,
linux-imx
On Fri, Jun 08, 2018 at 09:44:46PM +0800, Robin Gong wrote:
> The legacy sdma driver has below limitations or drawbacks:
> 1. Hardcode the max BDs number as "PAGE_SIZE / sizeof(*)", and alloc
> one page size for one channel regardless of only few BDs needed
> most time. But in few cases, the max PAGE_SIZE maybe not enough.
> 2. One SDMA channel can't stop immediatley once channel disabled which
> means SDMA interrupt may come in after this channel terminated.There
> are some patches for this corner case such as commit "2746e2c389f9",
> but not cover non-cyclic.
>
> The common virt-dma overcomes the above limitations. It can alloc bd
> dynamically and free bd once this tx transfer done. No memory wasted or
> maximum limititation here, only depends on how many memory can be requested
> from kernel. For No.2, such issue can be workaround by checking if there
> is available descript("sdmac->desc") now once the unwanted interrupt
> coming. At last the common virt-dma is easier for sdma driver maintain.
>
> The main changes as below:
> --new "sdma_desc" structure containing virt_dma_desc and some members
> which moved from "sdma_channel" such as "num_bd","bd_phys","bd",etc,
> since multi descriptors may exist on virtual dma framework
> rather than only one as before.
> --remove some members of "sdma_channel" structure since it's handled
> by virtual dma common framework, such as "tasklet", "dma_chan",etc.
> --add specific BD0 for channel0 since such bd descriptor is must and
> basic for other dma channel, no need alloc/free as other channel,so
> request it during probe.
> --remove sdma_request_channel(),sdma_tx_submit(),etc.
> --alloc/free bd descriptor added and code changes for virtual dma.
>
> Signed-off-by: Robin Gong <yibin.gong@nxp.com>
> ---
> drivers/dma/Kconfig | 1 +
> drivers/dma/imx-sdma.c | 332 ++++++++++++++++++++++++++++++++-----------------
> 2 files changed, 220 insertions(+), 113 deletions(-)
>
> diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
> index ca1680a..d4a4230 100644
> --- a/drivers/dma/Kconfig
> +++ b/drivers/dma/Kconfig
> @@ -250,6 +250,7 @@ config IMX_SDMA
> tristate "i.MX SDMA support"
> depends on ARCH_MXC
> select DMA_ENGINE
> + select DMA_VIRTUAL_CHANNELS
> help
> Support the i.MX SDMA engine. This engine is integrated into
> Freescale i.MX25/31/35/51/53/6 chips.
> diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
> index ccd03c3..8d0c1fd 100644
> --- a/drivers/dma/imx-sdma.c
> +++ b/drivers/dma/imx-sdma.c
> @@ -48,6 +48,7 @@
> #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
>
> #include "dmaengine.h"
> +#include "virt-dma.h"
>
> /* SDMA registers */
> #define SDMA_H_C0PTR 0x000
> @@ -296,6 +297,31 @@ struct sdma_context_data {
> struct sdma_engine;
>
> /**
> + * struct sdma_desc - descriptor structor for one transfer
> + * @vd descriptor for virt dma
> + * @num_bd max NUM_BD. number of descriptors currently handling
> + * @buf_tail ID of the buffer that was processed
> + * @buf_ptail ID of the previous buffer that was processed
> + * @period_len period length, used in cyclic.
> + * @chn_real_count the real count updated from bd->mode.count
> + * @chn_count the transfer count setuped
> + * @sdmac sdma_channel pointer
> + * @bd pointer of alloced bd
> + */
> +struct sdma_desc {
> + struct virt_dma_desc vd;
> + unsigned int num_bd;
> + dma_addr_t bd_phys;
> + unsigned int buf_tail;
> + unsigned int buf_ptail;
> + unsigned int period_len;
> + unsigned int chn_real_count;
> + unsigned int chn_count;
> + struct sdma_channel *sdmac;
> + struct sdma_buffer_descriptor *bd;
> +};
> +
> +/**
> * struct sdma_channel - housekeeping for a SDMA channel
> *
> * @sdma pointer to the SDMA engine for this channel
> @@ -305,11 +331,10 @@ struct sdma_engine;
> * @event_id0 aka dma request line
> * @event_id1 for channels that use 2 events
> * @word_size peripheral access size
> - * @buf_tail ID of the buffer that was processed
> - * @buf_ptail ID of the previous buffer that was processed
> - * @num_bd max NUM_BD. number of descriptors currently handling
> */
> struct sdma_channel {
> + struct virt_dma_chan vc;
> + struct sdma_desc *desc;
> struct sdma_engine *sdma;
> unsigned int channel;
> enum dma_transfer_direction direction;
> @@ -317,12 +342,6 @@ struct sdma_channel {
> unsigned int event_id0;
> unsigned int event_id1;
> enum dma_slave_buswidth word_size;
> - unsigned int buf_tail;
> - unsigned int buf_ptail;
> - unsigned int num_bd;
> - unsigned int period_len;
> - struct sdma_buffer_descriptor *bd;
> - dma_addr_t bd_phys;
> unsigned int pc_from_device, pc_to_device;
> unsigned int device_to_device;
> unsigned long flags;
> @@ -330,13 +349,10 @@ struct sdma_channel {
> unsigned long event_mask[2];
> unsigned long watermark_level;
> u32 shp_addr, per_addr;
> - struct dma_chan chan;
> spinlock_t lock;
> - struct dma_async_tx_descriptor desc;
> enum dma_status status;
> unsigned int chn_count;
> unsigned int chn_real_count;
These are no longer used here and should be removed.
Sascha
--
Pengutronix e.K. | |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v2 2/5] Revert "dmaengine: imx-sdma: fix pagefault when channel is disabled during interrupt"
2018-06-08 13:44 [PATCH v2 0/5] add virt-dma support for imx-sdma Robin Gong
2018-06-08 8:43 ` Sascha Hauer
2018-06-08 13:44 ` [PATCH v2 1/5] dmaengine: imx-sdma: add virt-dma support Robin Gong
@ 2018-06-08 13:44 ` Robin Gong
2018-06-08 13:44 ` [PATCH v2 3/5] dmaengine: imx-sdma: remove usless lock Robin Gong
` (2 subsequent siblings)
5 siblings, 0 replies; 9+ messages in thread
From: Robin Gong @ 2018-06-08 13:44 UTC (permalink / raw)
To: vkoul, s.hauer, dan.j.williams
Cc: dmaengine, linux-kernel, linux-arm-kernel, linux-imx
This reverts commit 2746e2c389f9d50043d21e2204270403efb9d62f.
Don't need this patch anymore,since we can easily check 'sdmac->desc' to avoid
handling dma interrupt after channel disabled if virt-dma used.
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
---
drivers/dma/imx-sdma.c | 21 ---------------------
1 file changed, 21 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 8d0c1fd..d93b58f 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -354,7 +354,6 @@ struct sdma_channel {
unsigned int chn_count;
unsigned int chn_real_count;
struct imx_dma_data data;
- bool enabled;
};
#define IMX_DMA_SG_LOOP BIT(0)
@@ -615,14 +614,7 @@ static int sdma_config_ownership(struct sdma_channel *sdmac,
static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
{
- unsigned long flags;
- struct sdma_channel *sdmac = &sdma->channel[channel];
-
writel(BIT(channel), sdma->regs + SDMA_H_START);
-
- spin_lock_irqsave(&sdmac->lock, flags);
- sdmac->enabled = true;
- spin_unlock_irqrestore(&sdmac->lock, flags);
}
/*
@@ -740,14 +732,6 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
struct sdma_buffer_descriptor *bd;
int error = 0;
enum dma_status old_status = sdmac->status;
- unsigned long flags;
-
- spin_lock_irqsave(&sdmac->lock, flags);
- if (!sdmac->enabled) {
- spin_unlock_irqrestore(&sdmac->lock, flags);
- return;
- }
- spin_unlock_irqrestore(&sdmac->lock, flags);
/*
* loop mode. Iterate over descriptors, re-setup them and
@@ -1008,15 +992,10 @@ static int sdma_disable_channel(struct dma_chan *chan)
struct sdma_channel *sdmac = to_sdma_chan(chan);
struct sdma_engine *sdma = sdmac->sdma;
int channel = sdmac->channel;
- unsigned long flags;
writel_relaxed(BIT(channel), sdma->regs + SDMA_H_STATSTOP);
sdmac->status = DMA_ERROR;
- spin_lock_irqsave(&sdmac->lock, flags);
- sdmac->enabled = false;
- spin_unlock_irqrestore(&sdmac->lock, flags);
-
return 0;
}
--
2.7.4
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH v2 3/5] dmaengine: imx-sdma: remove usless lock
2018-06-08 13:44 [PATCH v2 0/5] add virt-dma support for imx-sdma Robin Gong
` (2 preceding siblings ...)
2018-06-08 13:44 ` [PATCH v2 2/5] Revert "dmaengine: imx-sdma: fix pagefault when channel is disabled during interrupt" Robin Gong
@ 2018-06-08 13:44 ` Robin Gong
2018-06-08 13:44 ` [PATCH v2 4/5] dmaengine: imx-sdma: remove the maximum limation for bd numbers Robin Gong
2018-06-08 13:44 ` [PATCH v2 5/5] dmaengine: imx-sdma: add sdma_transfer_init to decrease code overlap Robin Gong
5 siblings, 0 replies; 9+ messages in thread
From: Robin Gong @ 2018-06-08 13:44 UTC (permalink / raw)
To: vkoul, s.hauer, dan.j.williams
Cc: dmaengine, linux-kernel, linux-arm-kernel, linux-imx
No need anymore for 'lock' now since virtual dma will provide
the common lock instead.
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
---
drivers/dma/imx-sdma.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index d93b58f..6faec89 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -349,7 +349,6 @@ struct sdma_channel {
unsigned long event_mask[2];
unsigned long watermark_level;
u32 shp_addr, per_addr;
- spinlock_t lock;
enum dma_status status;
unsigned int chn_count;
unsigned int chn_real_count;
@@ -1908,7 +1907,6 @@ static int sdma_probe(struct platform_device *pdev)
struct sdma_channel *sdmac = &sdma->channel[i];
sdmac->sdma = sdma;
- spin_lock_init(&sdmac->lock);
sdmac->channel = i;
sdmac->vc.desc_free = sdma_desc_free;
--
2.7.4
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH v2 4/5] dmaengine: imx-sdma: remove the maximum limation for bd numbers
2018-06-08 13:44 [PATCH v2 0/5] add virt-dma support for imx-sdma Robin Gong
` (3 preceding siblings ...)
2018-06-08 13:44 ` [PATCH v2 3/5] dmaengine: imx-sdma: remove usless lock Robin Gong
@ 2018-06-08 13:44 ` Robin Gong
2018-06-08 13:44 ` [PATCH v2 5/5] dmaengine: imx-sdma: add sdma_transfer_init to decrease code overlap Robin Gong
5 siblings, 0 replies; 9+ messages in thread
From: Robin Gong @ 2018-06-08 13:44 UTC (permalink / raw)
To: vkoul, s.hauer, dan.j.williams
Cc: dmaengine, linux-kernel, linux-arm-kernel, linux-imx
No this limitation now after virtual dma used since bd is allocated
dynamically instead of static.
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
---
drivers/dma/imx-sdma.c | 14 --------------
1 file changed, 14 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 6faec89..afaee72 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -292,7 +292,6 @@ struct sdma_context_data {
u32 scratch7;
} __attribute__ ((packed));
-#define NUM_BD (int)(PAGE_SIZE / sizeof(struct sdma_buffer_descriptor))
struct sdma_engine;
@@ -1297,13 +1296,6 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
if (ret)
goto err_bd_out;
- if (sg_len > NUM_BD) {
- dev_err(sdma->dev, "SDMA channel %d: maximum number of sg exceeded: %d > %d\n",
- channel, sg_len, NUM_BD);
- ret = -EINVAL;
- goto err_bd_out;
- }
-
desc->chn_count = 0;
for_each_sg(sgl, sg, sg_len, i) {
struct sdma_buffer_descriptor *bd = &desc->bd[i];
@@ -1413,12 +1405,6 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
if (ret)
goto err_bd_out;
- if (num_periods > NUM_BD) {
- dev_err(sdma->dev, "SDMA channel %d: maximum number of sg exceeded: %d > %d\n",
- channel, num_periods, NUM_BD);
- goto err_bd_out;
- }
-
if (period_len > 0xffff) {
dev_err(sdma->dev, "SDMA channel %d: maximum period size exceeded: %zu > %d\n",
channel, period_len, 0xffff);
--
2.7.4
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH v2 5/5] dmaengine: imx-sdma: add sdma_transfer_init to decrease code overlap
2018-06-08 13:44 [PATCH v2 0/5] add virt-dma support for imx-sdma Robin Gong
` (4 preceding siblings ...)
2018-06-08 13:44 ` [PATCH v2 4/5] dmaengine: imx-sdma: remove the maximum limation for bd numbers Robin Gong
@ 2018-06-08 13:44 ` Robin Gong
5 siblings, 0 replies; 9+ messages in thread
From: Robin Gong @ 2018-06-08 13:44 UTC (permalink / raw)
To: vkoul, s.hauer, dan.j.williams
Cc: dmaengine, linux-kernel, linux-arm-kernel, linux-imx
There are lot of codes overlap between prep_sg and prep_cyclic function.
Add sdma_transfer_init() function to elimated the code overlap.
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
---
drivers/dma/imx-sdma.c | 83 ++++++++++++++++++++++----------------------------
1 file changed, 37 insertions(+), 46 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index afaee72..25de89e 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -1255,6 +1255,40 @@ static void sdma_free_chan_resources(struct dma_chan *chan)
clk_disable(sdma->clk_ahb);
}
+static struct sdma_desc *sdma_transfer_init(struct sdma_channel *sdmac,
+ enum dma_transfer_direction direction, u32 bds)
+{
+ struct sdma_desc *desc;
+
+ desc = kzalloc((sizeof(*desc)), GFP_KERNEL);
+ if (!desc)
+ goto err_out;
+
+ sdmac->status = DMA_IN_PROGRESS;
+ sdmac->direction = direction;
+ sdmac->flags = 0;
+
+ desc->chn_count = 0;
+ desc->chn_real_count = 0;
+ desc->buf_tail = 0;
+ desc->buf_ptail = 0;
+ desc->sdmac = sdmac;
+ desc->num_bd = bds;
+
+ if (sdma_alloc_bd(desc))
+ goto err_desc_out;
+
+ if (sdma_load_context(sdmac))
+ goto err_desc_out;
+
+ return desc;
+
+err_desc_out:
+ kfree(desc);
+err_out:
+ return NULL;
+}
+
static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
struct dma_chan *chan, struct scatterlist *sgl,
unsigned int sg_len, enum dma_transfer_direction direction,
@@ -1267,36 +1301,13 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
struct scatterlist *sg;
struct sdma_desc *desc;
- if (sdmac->status == DMA_IN_PROGRESS)
- return NULL;
- sdmac->status = DMA_IN_PROGRESS;
-
- sdmac->flags = 0;
-
- desc = kzalloc((sizeof(*desc)), GFP_KERNEL);
+ desc = sdma_transfer_init(sdmac, direction, sg_len);
if (!desc)
goto err_out;
- desc->buf_tail = 0;
- desc->buf_ptail = 0;
- desc->sdmac = sdmac;
- desc->num_bd = sg_len;
- desc->chn_real_count = 0;
-
- if (sdma_alloc_bd(desc)) {
- kfree(desc);
- goto err_out;
- }
-
dev_dbg(sdma->dev, "setting up %d entries for channel %d.\n",
sg_len, channel);
- sdmac->direction = direction;
- ret = sdma_load_context(sdmac);
- if (ret)
- goto err_bd_out;
-
- desc->chn_count = 0;
for_each_sg(sgl, sg, sg_len, i) {
struct sdma_buffer_descriptor *bd = &desc->bd[i];
int param;
@@ -1372,38 +1383,18 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
struct sdma_engine *sdma = sdmac->sdma;
int num_periods = buf_len / period_len;
int channel = sdmac->channel;
- int ret, i = 0, buf = 0;
+ int i = 0, buf = 0;
struct sdma_desc *desc;
dev_dbg(sdma->dev, "%s channel: %d\n", __func__, channel);
- if (sdmac->status == DMA_IN_PROGRESS)
- return NULL;
- sdmac->status = DMA_IN_PROGRESS;
-
- desc = kzalloc((sizeof(*desc)), GFP_KERNEL);
+ desc = sdma_transfer_init(sdmac, direction, num_periods);
if (!desc)
goto err_out;
-
- desc->buf_tail = 0;
- desc->buf_ptail = 0;
- desc->sdmac = sdmac;
- desc->num_bd = num_periods;
- desc->chn_real_count = 0;
desc->period_len = period_len;
sdmac->flags |= IMX_DMA_SG_LOOP;
- sdmac->direction = direction;
-
- if (sdma_alloc_bd(desc)) {
- kfree(desc);
- goto err_out;
- }
-
- ret = sdma_load_context(sdmac);
- if (ret)
- goto err_bd_out;
if (period_len > 0xffff) {
dev_err(sdma->dev, "SDMA channel %d: maximum period size exceeded: %zu > %d\n",
--
2.7.4
^ permalink raw reply related [flat|nested] 9+ messages in thread