Add support for dma-channel-mask so that only the specified channels
are used. This helps to reserve some channels for the firmware.
This was initially achieved by limiting the channel number to 31 in
the driver and adjusting the register address to skip channel0 which
was reserved for a firmware. Now, with this change, the driver can
align more to the actual hardware which has 32 channels.
Signed-off-by: Akhil R <[email protected]>
---
drivers/dma/tegra186-gpc-dma.c | 35 ++++++++++++++++++++++++++++------
1 file changed, 29 insertions(+), 6 deletions(-)
diff --git a/drivers/dma/tegra186-gpc-dma.c b/drivers/dma/tegra186-gpc-dma.c
index fa9bda4a2bc6..f69a800c4f80 100644
--- a/drivers/dma/tegra186-gpc-dma.c
+++ b/drivers/dma/tegra186-gpc-dma.c
@@ -161,7 +161,10 @@
#define TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT 5000 /* 5 msec */
/* Channel base address offset from GPCDMA base address */
-#define TEGRA_GPCDMA_CHANNEL_BASE_ADD_OFFSET 0x20000
+#define TEGRA_GPCDMA_CHANNEL_BASE_ADDR_OFFSET 0x10000
+
+/* Default channel mask reserving channel0 */
+#define TEGRA_GPCDMA_DEFAULT_CHANNEL_MASK 0xfffffffe
struct tegra_dma;
struct tegra_dma_channel;
@@ -246,6 +249,7 @@ struct tegra_dma {
const struct tegra_dma_chip_data *chip_data;
unsigned long sid_m2d_reserved;
unsigned long sid_d2m_reserved;
+ u32 chan_mask;
void __iomem *base_addr;
struct device *dev;
struct dma_device dma_dev;
@@ -1288,7 +1292,7 @@ static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
}
static const struct tegra_dma_chip_data tegra186_dma_chip_data = {
- .nr_channels = 31,
+ .nr_channels = 32,
.channel_reg_size = SZ_64K,
.max_dma_count = SZ_1G,
.hw_support_pause = false,
@@ -1296,7 +1300,7 @@ static const struct tegra_dma_chip_data tegra186_dma_chip_data = {
};
static const struct tegra_dma_chip_data tegra194_dma_chip_data = {
- .nr_channels = 31,
+ .nr_channels = 32,
.channel_reg_size = SZ_64K,
.max_dma_count = SZ_1G,
.hw_support_pause = true,
@@ -1304,7 +1308,7 @@ static const struct tegra_dma_chip_data tegra194_dma_chip_data = {
};
static const struct tegra_dma_chip_data tegra234_dma_chip_data = {
- .nr_channels = 31,
+ .nr_channels = 32,
.channel_reg_size = SZ_64K,
.max_dma_count = SZ_1G,
.hw_support_pause = true,
@@ -1380,15 +1384,28 @@ static int tegra_dma_probe(struct platform_device *pdev)
}
stream_id = iommu_spec->ids[0] & 0xffff;
+ ret = device_property_read_u32(&pdev->dev, "dma-channel-mask",
+ &tdma->chan_mask);
+ if (ret) {
+ dev_warn(&pdev->dev,
+ "Missing dma-channel-mask property, using default channel mask %#x\n",
+ TEGRA_GPCDMA_DEFAULT_CHANNEL_MASK);
+ tdma->chan_mask = TEGRA_GPCDMA_DEFAULT_CHANNEL_MASK;
+ }
+
INIT_LIST_HEAD(&tdma->dma_dev.channels);
for (i = 0; i < cdata->nr_channels; i++) {
struct tegra_dma_channel *tdc = &tdma->channels[i];
+ /* Check for channel mask */
+ if (!((1 << i) & tdma->chan_mask))
+ continue;
+
tdc->irq = platform_get_irq(pdev, i);
if (tdc->irq < 0)
return tdc->irq;
- tdc->chan_base_offset = TEGRA_GPCDMA_CHANNEL_BASE_ADD_OFFSET +
+ tdc->chan_base_offset = TEGRA_GPCDMA_CHANNEL_BASE_ADDR_OFFSET +
i * cdata->channel_reg_size;
snprintf(tdc->name, sizeof(tdc->name), "gpcdma.%d", i);
tdc->tdma = tdma;
@@ -1450,7 +1467,7 @@ static int tegra_dma_probe(struct platform_device *pdev)
}
dev_info(&pdev->dev, "GPC DMA driver register %d channels\n",
- cdata->nr_channels);
+ hweight_long(tdma->chan_mask));
return 0;
}
@@ -1473,6 +1490,9 @@ static int __maybe_unused tegra_dma_pm_suspend(struct device *dev)
for (i = 0; i < tdma->chip_data->nr_channels; i++) {
struct tegra_dma_channel *tdc = &tdma->channels[i];
+ if (!((1 << i) & tdma->chan_mask))
+ continue;
+
if (tdc->dma_desc) {
dev_err(tdma->dev, "channel %u busy\n", i);
return -EBUSY;
@@ -1492,6 +1512,9 @@ static int __maybe_unused tegra_dma_pm_resume(struct device *dev)
for (i = 0; i < tdma->chip_data->nr_channels; i++) {
struct tegra_dma_channel *tdc = &tdma->channels[i];
+ if (!((1 << i) & tdma->chan_mask))
+ continue;
+
tegra_dma_program_sid(tdc, tdc->stream_id);
}
--
2.17.1
Hi Akhil,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on robh/for-next]
[also build test WARNING on vkoul-dmaengine/next linus/master v6.0-rc5 next-20220913]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Akhil-R/Tegra-GCPDMA-Add-dma-channel-mask-support/20220914-010611
base: https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
config: loongarch-allyesconfig (https://download.01.org/0day-ci/archive/20220914/[email protected]/config)
compiler: loongarch64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/b760183e9631ceaf2f36072fc4a7438c3d62887b
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Akhil-R/Tegra-GCPDMA-Add-dma-channel-mask-support/20220914-010611
git checkout b760183e9631ceaf2f36072fc4a7438c3d62887b
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=loongarch SHELL=/bin/bash drivers/
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <[email protected]>
All warnings (new ones prefixed by >>):
In file included from include/linux/device.h:15,
from include/linux/dmaengine.h:8,
from drivers/dma/tegra186-gpc-dma.c:9:
drivers/dma/tegra186-gpc-dma.c: In function 'tegra_dma_probe':
>> drivers/dma/tegra186-gpc-dma.c:1469:30: warning: format '%d' expects argument of type 'int', but argument 3 has type 'long unsigned int' [-Wformat=]
1469 | dev_info(&pdev->dev, "GPC DMA driver register %d channels\n",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/dev_printk.h:110:30: note: in definition of macro 'dev_printk_index_wrap'
110 | _p_func(dev, fmt, ##__VA_ARGS__); \
| ^~~
include/linux/dev_printk.h:150:58: note: in expansion of macro 'dev_fmt'
150 | dev_printk_index_wrap(_dev_info, KERN_INFO, dev, dev_fmt(fmt), ##__VA_ARGS__)
| ^~~~~~~
drivers/dma/tegra186-gpc-dma.c:1469:9: note: in expansion of macro 'dev_info'
1469 | dev_info(&pdev->dev, "GPC DMA driver register %d channels\n",
| ^~~~~~~~
drivers/dma/tegra186-gpc-dma.c:1469:56: note: format string is defined here
1469 | dev_info(&pdev->dev, "GPC DMA driver register %d channels\n",
| ~^
| |
| int
| %ld
vim +1469 drivers/dma/tegra186-gpc-dma.c
ee17028009d49f Akhil R 2022-02-25 1346
ee17028009d49f Akhil R 2022-02-25 1347 static int tegra_dma_probe(struct platform_device *pdev)
ee17028009d49f Akhil R 2022-02-25 1348 {
ee17028009d49f Akhil R 2022-02-25 1349 const struct tegra_dma_chip_data *cdata = NULL;
ee17028009d49f Akhil R 2022-02-25 1350 struct iommu_fwspec *iommu_spec;
ee17028009d49f Akhil R 2022-02-25 1351 unsigned int stream_id, i;
ee17028009d49f Akhil R 2022-02-25 1352 struct tegra_dma *tdma;
ee17028009d49f Akhil R 2022-02-25 1353 int ret;
ee17028009d49f Akhil R 2022-02-25 1354
ee17028009d49f Akhil R 2022-02-25 1355 cdata = of_device_get_match_data(&pdev->dev);
ee17028009d49f Akhil R 2022-02-25 1356
ee17028009d49f Akhil R 2022-02-25 1357 tdma = devm_kzalloc(&pdev->dev,
ee17028009d49f Akhil R 2022-02-25 1358 struct_size(tdma, channels, cdata->nr_channels),
ee17028009d49f Akhil R 2022-02-25 1359 GFP_KERNEL);
ee17028009d49f Akhil R 2022-02-25 1360 if (!tdma)
ee17028009d49f Akhil R 2022-02-25 1361 return -ENOMEM;
ee17028009d49f Akhil R 2022-02-25 1362
ee17028009d49f Akhil R 2022-02-25 1363 tdma->dev = &pdev->dev;
ee17028009d49f Akhil R 2022-02-25 1364 tdma->chip_data = cdata;
ee17028009d49f Akhil R 2022-02-25 1365 platform_set_drvdata(pdev, tdma);
ee17028009d49f Akhil R 2022-02-25 1366
ee17028009d49f Akhil R 2022-02-25 1367 tdma->base_addr = devm_platform_ioremap_resource(pdev, 0);
ee17028009d49f Akhil R 2022-02-25 1368 if (IS_ERR(tdma->base_addr))
ee17028009d49f Akhil R 2022-02-25 1369 return PTR_ERR(tdma->base_addr);
ee17028009d49f Akhil R 2022-02-25 1370
ee17028009d49f Akhil R 2022-02-25 1371 tdma->rst = devm_reset_control_get_exclusive(&pdev->dev, "gpcdma");
ee17028009d49f Akhil R 2022-02-25 1372 if (IS_ERR(tdma->rst)) {
ee17028009d49f Akhil R 2022-02-25 1373 return dev_err_probe(&pdev->dev, PTR_ERR(tdma->rst),
ee17028009d49f Akhil R 2022-02-25 1374 "Missing controller reset\n");
ee17028009d49f Akhil R 2022-02-25 1375 }
ee17028009d49f Akhil R 2022-02-25 1376 reset_control_reset(tdma->rst);
ee17028009d49f Akhil R 2022-02-25 1377
ee17028009d49f Akhil R 2022-02-25 1378 tdma->dma_dev.dev = &pdev->dev;
ee17028009d49f Akhil R 2022-02-25 1379
ee17028009d49f Akhil R 2022-02-25 1380 iommu_spec = dev_iommu_fwspec_get(&pdev->dev);
ee17028009d49f Akhil R 2022-02-25 1381 if (!iommu_spec) {
ee17028009d49f Akhil R 2022-02-25 1382 dev_err(&pdev->dev, "Missing iommu stream-id\n");
ee17028009d49f Akhil R 2022-02-25 1383 return -EINVAL;
ee17028009d49f Akhil R 2022-02-25 1384 }
ee17028009d49f Akhil R 2022-02-25 1385 stream_id = iommu_spec->ids[0] & 0xffff;
ee17028009d49f Akhil R 2022-02-25 1386
b760183e9631ce Akhil R 2022-09-13 1387 ret = device_property_read_u32(&pdev->dev, "dma-channel-mask",
b760183e9631ce Akhil R 2022-09-13 1388 &tdma->chan_mask);
b760183e9631ce Akhil R 2022-09-13 1389 if (ret) {
b760183e9631ce Akhil R 2022-09-13 1390 dev_warn(&pdev->dev,
b760183e9631ce Akhil R 2022-09-13 1391 "Missing dma-channel-mask property, using default channel mask %#x\n",
b760183e9631ce Akhil R 2022-09-13 1392 TEGRA_GPCDMA_DEFAULT_CHANNEL_MASK);
b760183e9631ce Akhil R 2022-09-13 1393 tdma->chan_mask = TEGRA_GPCDMA_DEFAULT_CHANNEL_MASK;
b760183e9631ce Akhil R 2022-09-13 1394 }
b760183e9631ce Akhil R 2022-09-13 1395
ee17028009d49f Akhil R 2022-02-25 1396 INIT_LIST_HEAD(&tdma->dma_dev.channels);
ee17028009d49f Akhil R 2022-02-25 1397 for (i = 0; i < cdata->nr_channels; i++) {
ee17028009d49f Akhil R 2022-02-25 1398 struct tegra_dma_channel *tdc = &tdma->channels[i];
ee17028009d49f Akhil R 2022-02-25 1399
b760183e9631ce Akhil R 2022-09-13 1400 /* Check for channel mask */
b760183e9631ce Akhil R 2022-09-13 1401 if (!((1 << i) & tdma->chan_mask))
b760183e9631ce Akhil R 2022-09-13 1402 continue;
b760183e9631ce Akhil R 2022-09-13 1403
461cd3709f266d Akhil R 2022-05-05 1404 tdc->irq = platform_get_irq(pdev, i);
461cd3709f266d Akhil R 2022-05-05 1405 if (tdc->irq < 0)
461cd3709f266d Akhil R 2022-05-05 1406 return tdc->irq;
461cd3709f266d Akhil R 2022-05-05 1407
b760183e9631ce Akhil R 2022-09-13 1408 tdc->chan_base_offset = TEGRA_GPCDMA_CHANNEL_BASE_ADDR_OFFSET +
ee17028009d49f Akhil R 2022-02-25 1409 i * cdata->channel_reg_size;
ee17028009d49f Akhil R 2022-02-25 1410 snprintf(tdc->name, sizeof(tdc->name), "gpcdma.%d", i);
ee17028009d49f Akhil R 2022-02-25 1411 tdc->tdma = tdma;
ee17028009d49f Akhil R 2022-02-25 1412 tdc->id = i;
ee17028009d49f Akhil R 2022-02-25 1413 tdc->slave_id = -1;
ee17028009d49f Akhil R 2022-02-25 1414
ee17028009d49f Akhil R 2022-02-25 1415 vchan_init(&tdc->vc, &tdma->dma_dev);
ee17028009d49f Akhil R 2022-02-25 1416 tdc->vc.desc_free = tegra_dma_desc_free;
ee17028009d49f Akhil R 2022-02-25 1417
ee17028009d49f Akhil R 2022-02-25 1418 /* program stream-id for this channel */
ee17028009d49f Akhil R 2022-02-25 1419 tegra_dma_program_sid(tdc, stream_id);
ee17028009d49f Akhil R 2022-02-25 1420 tdc->stream_id = stream_id;
ee17028009d49f Akhil R 2022-02-25 1421 }
ee17028009d49f Akhil R 2022-02-25 1422
ee17028009d49f Akhil R 2022-02-25 1423 dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
ee17028009d49f Akhil R 2022-02-25 1424 dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
ee17028009d49f Akhil R 2022-02-25 1425 dma_cap_set(DMA_MEMCPY, tdma->dma_dev.cap_mask);
ee17028009d49f Akhil R 2022-02-25 1426 dma_cap_set(DMA_MEMSET, tdma->dma_dev.cap_mask);
ee17028009d49f Akhil R 2022-02-25 1427 dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask);
ee17028009d49f Akhil R 2022-02-25 1428
ee17028009d49f Akhil R 2022-02-25 1429 /*
ee17028009d49f Akhil R 2022-02-25 1430 * Only word aligned transfers are supported. Set the copy
ee17028009d49f Akhil R 2022-02-25 1431 * alignment shift.
ee17028009d49f Akhil R 2022-02-25 1432 */
ee17028009d49f Akhil R 2022-02-25 1433 tdma->dma_dev.copy_align = 2;
ee17028009d49f Akhil R 2022-02-25 1434 tdma->dma_dev.fill_align = 2;
ee17028009d49f Akhil R 2022-02-25 1435 tdma->dma_dev.device_alloc_chan_resources =
ee17028009d49f Akhil R 2022-02-25 1436 tegra_dma_alloc_chan_resources;
ee17028009d49f Akhil R 2022-02-25 1437 tdma->dma_dev.device_free_chan_resources =
ee17028009d49f Akhil R 2022-02-25 1438 tegra_dma_free_chan_resources;
ee17028009d49f Akhil R 2022-02-25 1439 tdma->dma_dev.device_prep_slave_sg = tegra_dma_prep_slave_sg;
ee17028009d49f Akhil R 2022-02-25 1440 tdma->dma_dev.device_prep_dma_memcpy = tegra_dma_prep_dma_memcpy;
ee17028009d49f Akhil R 2022-02-25 1441 tdma->dma_dev.device_prep_dma_memset = tegra_dma_prep_dma_memset;
ee17028009d49f Akhil R 2022-02-25 1442 tdma->dma_dev.device_prep_dma_cyclic = tegra_dma_prep_dma_cyclic;
ee17028009d49f Akhil R 2022-02-25 1443 tdma->dma_dev.device_config = tegra_dma_slave_config;
ee17028009d49f Akhil R 2022-02-25 1444 tdma->dma_dev.device_terminate_all = tegra_dma_terminate_all;
ee17028009d49f Akhil R 2022-02-25 1445 tdma->dma_dev.device_tx_status = tegra_dma_tx_status;
ee17028009d49f Akhil R 2022-02-25 1446 tdma->dma_dev.device_issue_pending = tegra_dma_issue_pending;
ee17028009d49f Akhil R 2022-02-25 1447 tdma->dma_dev.device_pause = tegra_dma_device_pause;
ee17028009d49f Akhil R 2022-02-25 1448 tdma->dma_dev.device_resume = tegra_dma_device_resume;
ee17028009d49f Akhil R 2022-02-25 1449 tdma->dma_dev.device_synchronize = tegra_dma_chan_synchronize;
ee17028009d49f Akhil R 2022-02-25 1450 tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
ee17028009d49f Akhil R 2022-02-25 1451
ee17028009d49f Akhil R 2022-02-25 1452 ret = dma_async_device_register(&tdma->dma_dev);
ee17028009d49f Akhil R 2022-02-25 1453 if (ret < 0) {
ee17028009d49f Akhil R 2022-02-25 1454 dev_err_probe(&pdev->dev, ret,
ee17028009d49f Akhil R 2022-02-25 1455 "GPC DMA driver registration failed\n");
ee17028009d49f Akhil R 2022-02-25 1456 return ret;
ee17028009d49f Akhil R 2022-02-25 1457 }
ee17028009d49f Akhil R 2022-02-25 1458
ee17028009d49f Akhil R 2022-02-25 1459 ret = of_dma_controller_register(pdev->dev.of_node,
ee17028009d49f Akhil R 2022-02-25 1460 tegra_dma_of_xlate, tdma);
ee17028009d49f Akhil R 2022-02-25 1461 if (ret < 0) {
ee17028009d49f Akhil R 2022-02-25 1462 dev_err_probe(&pdev->dev, ret,
ee17028009d49f Akhil R 2022-02-25 1463 "GPC DMA OF registration failed\n");
ee17028009d49f Akhil R 2022-02-25 1464
ee17028009d49f Akhil R 2022-02-25 1465 dma_async_device_unregister(&tdma->dma_dev);
ee17028009d49f Akhil R 2022-02-25 1466 return ret;
ee17028009d49f Akhil R 2022-02-25 1467 }
ee17028009d49f Akhil R 2022-02-25 1468
ee17028009d49f Akhil R 2022-02-25 @1469 dev_info(&pdev->dev, "GPC DMA driver register %d channels\n",
b760183e9631ce Akhil R 2022-09-13 1470 hweight_long(tdma->chan_mask));
ee17028009d49f Akhil R 2022-02-25 1471
ee17028009d49f Akhil R 2022-02-25 1472 return 0;
ee17028009d49f Akhil R 2022-02-25 1473 }
ee17028009d49f Akhil R 2022-02-25 1474
--
0-DAY CI Kernel Test Service
https://01.org/lkp
On Tue, Sep 13, 2022 at 09:22:51PM +0530, Akhil R wrote:
> Add support for dma-channel-mask so that only the specified channels
> are used. This helps to reserve some channels for the firmware.
>
> This was initially achieved by limiting the channel number to 31 in
> the driver and adjusting the register address to skip channel0 which
> was reserved for a firmware. Now, with this change, the driver can
> align more to the actual hardware which has 32 channels.
>
> Signed-off-by: Akhil R <[email protected]>
> ---
> drivers/dma/tegra186-gpc-dma.c | 35 ++++++++++++++++++++++++++++------
> 1 file changed, 29 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/dma/tegra186-gpc-dma.c b/drivers/dma/tegra186-gpc-dma.c
> index fa9bda4a2bc6..f69a800c4f80 100644
> --- a/drivers/dma/tegra186-gpc-dma.c
> +++ b/drivers/dma/tegra186-gpc-dma.c
> @@ -161,7 +161,10 @@
> #define TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT 5000 /* 5 msec */
>
> /* Channel base address offset from GPCDMA base address */
> -#define TEGRA_GPCDMA_CHANNEL_BASE_ADD_OFFSET 0x20000
> +#define TEGRA_GPCDMA_CHANNEL_BASE_ADDR_OFFSET 0x10000
> +
> +/* Default channel mask reserving channel0 */
> +#define TEGRA_GPCDMA_DEFAULT_CHANNEL_MASK 0xfffffffe
>
> struct tegra_dma;
> struct tegra_dma_channel;
> @@ -246,6 +249,7 @@ struct tegra_dma {
> const struct tegra_dma_chip_data *chip_data;
> unsigned long sid_m2d_reserved;
> unsigned long sid_d2m_reserved;
> + u32 chan_mask;
> void __iomem *base_addr;
> struct device *dev;
> struct dma_device dma_dev;
> @@ -1288,7 +1292,7 @@ static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
> }
>
> static const struct tegra_dma_chip_data tegra186_dma_chip_data = {
> - .nr_channels = 31,
> + .nr_channels = 32,
> .channel_reg_size = SZ_64K,
> .max_dma_count = SZ_1G,
> .hw_support_pause = false,
> @@ -1296,7 +1300,7 @@ static const struct tegra_dma_chip_data tegra186_dma_chip_data = {
> };
>
> static const struct tegra_dma_chip_data tegra194_dma_chip_data = {
> - .nr_channels = 31,
> + .nr_channels = 32,
> .channel_reg_size = SZ_64K,
> .max_dma_count = SZ_1G,
> .hw_support_pause = true,
> @@ -1304,7 +1308,7 @@ static const struct tegra_dma_chip_data tegra194_dma_chip_data = {
> };
>
> static const struct tegra_dma_chip_data tegra234_dma_chip_data = {
> - .nr_channels = 31,
> + .nr_channels = 32,
> .channel_reg_size = SZ_64K,
> .max_dma_count = SZ_1G,
> .hw_support_pause = true,
> @@ -1380,15 +1384,28 @@ static int tegra_dma_probe(struct platform_device *pdev)
> }
> stream_id = iommu_spec->ids[0] & 0xffff;
>
> + ret = device_property_read_u32(&pdev->dev, "dma-channel-mask",
> + &tdma->chan_mask);
> + if (ret) {
> + dev_warn(&pdev->dev,
> + "Missing dma-channel-mask property, using default channel mask %#x\n",
> + TEGRA_GPCDMA_DEFAULT_CHANNEL_MASK);
> + tdma->chan_mask = TEGRA_GPCDMA_DEFAULT_CHANNEL_MASK;
> + }
> +
> INIT_LIST_HEAD(&tdma->dma_dev.channels);
> for (i = 0; i < cdata->nr_channels; i++) {
> struct tegra_dma_channel *tdc = &tdma->channels[i];
>
> + /* Check for channel mask */
> + if (!((1 << i) & tdma->chan_mask))
It's more idiomatic to reverse the operands and use the BIT macro, which
checkpatch should've warned about:
if (!(tdma->chan_mask & BIT(i)))
There's a few other occurrences of that below.
Thierry
> + continue;
> +
> tdc->irq = platform_get_irq(pdev, i);
> if (tdc->irq < 0)
> return tdc->irq;
>
> - tdc->chan_base_offset = TEGRA_GPCDMA_CHANNEL_BASE_ADD_OFFSET +
> + tdc->chan_base_offset = TEGRA_GPCDMA_CHANNEL_BASE_ADDR_OFFSET +
> i * cdata->channel_reg_size;
> snprintf(tdc->name, sizeof(tdc->name), "gpcdma.%d", i);
> tdc->tdma = tdma;
> @@ -1450,7 +1467,7 @@ static int tegra_dma_probe(struct platform_device *pdev)
> }
>
> dev_info(&pdev->dev, "GPC DMA driver register %d channels\n",
> - cdata->nr_channels);
> + hweight_long(tdma->chan_mask));
>
> return 0;
> }
> @@ -1473,6 +1490,9 @@ static int __maybe_unused tegra_dma_pm_suspend(struct device *dev)
> for (i = 0; i < tdma->chip_data->nr_channels; i++) {
> struct tegra_dma_channel *tdc = &tdma->channels[i];
>
> + if (!((1 << i) & tdma->chan_mask))
> + continue;
> +
> if (tdc->dma_desc) {
> dev_err(tdma->dev, "channel %u busy\n", i);
> return -EBUSY;
> @@ -1492,6 +1512,9 @@ static int __maybe_unused tegra_dma_pm_resume(struct device *dev)
> for (i = 0; i < tdma->chip_data->nr_channels; i++) {
> struct tegra_dma_channel *tdc = &tdma->channels[i];
>
> + if (!((1 << i) & tdma->chan_mask))
> + continue;
> +
> tegra_dma_program_sid(tdc, tdc->stream_id);
> }
>
> --
> 2.17.1
>