[PATCH] dmaengine: DW DMAC: split pdata to hardware properties and platform quirks
Andy Shevchenko
andriy.shevchenko at linux.intel.com
Thu Oct 20 03:48:21 PDT 2016
On Thu, 2016-09-15 at 16:14 +0300, Eugeniy Paltsev wrote:
> This patch is to address a proposal by Andy in this thread:
> http://www.spinics.net/lists/dmaengine/msg10754.html
> Split platform data to actual hardware properties, and platform
> quirks.
> Now we able to use quirks and hardware properties separately from
> different sources (pdata, device tree or autoconfig registers)
>
My comments below.
Sorry for delayed answer.
> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev at synopsys.com>
> ---
> drivers/dma/dw/core.c | 31 +++++++++++++++-----------
> drivers/dma/dw/platform.c | 42 +++++++++++++++++++++----
> -----------
> include/linux/platform_data/dma-dw.h | 20 +++++++++++------
> 3 files changed, 57 insertions(+), 36 deletions(-)
>
> diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
> index c2c0a61..9352735 100644
> --- a/drivers/dma/dw/core.c
> +++ b/drivers/dma/dw/core.c
> @@ -1451,10 +1451,25 @@ int dw_dma_probe(struct dw_dma_chip *chip)
>
> dw->regs = chip->regs;
> chip->dw = dw;
+ empty line.
> + /* Reassign the platform data pointer */
> + pdata = dw->pdata;
>
> pm_runtime_get_sync(chip->dev);
>
> - if (!chip->pdata) {
> + if ((!chip->pdata) ||
> + (chip->pdata && test_bit(QUIRKS_ONLY_USED, &chip->pdata-
I don't think you need atomic test / set of those bits.
> >quirks))) {
> +
> + /*
> + * Fill quirks with the default values in case of
> pdata absence
/*
* Multi-line comments should include full sentences
* (punctuation matters).
*/
> + */
> + if (!chip->pdata) {
> + set_bit(QUIRKS_IS_PRIVATE, &pdata->quirks);
> + set_bit(QUIRKS_IS_MEMCPY, &pdata->quirks);
> + set_bit(QUIRKS_IS_NOLLP, &pdata->quirks);
> + } else {
> + pdata->quirks = chip->pdata->quirks;
> + }
> +
> dw_params = dma_readl(dw, DW_PARAMS);
> dev_dbg(chip->dev, "DW_PARAMS: 0x%08x\n", dw_params);
>
> @@ -1464,9 +1479,6 @@ int dw_dma_probe(struct dw_dma_chip *chip)
> goto err_pdata;
> }
>
> - /* Reassign the platform data pointer */
> - pdata = dw->pdata;
> -
> /* Get hardware configuration parameters */
> pdata->nr_channels = (dw_params >> DW_PARAMS_NR_CHAN
> & 7) + 1;
> pdata->nr_masters = (dw_params >> DW_PARAMS_NR_MASTER
> & 3) + 1;
> @@ -1477,8 +1489,6 @@ int dw_dma_probe(struct dw_dma_chip *chip)
> pdata->block_size = dma_readl(dw, MAX_BLK_SIZE);
>
> /* Fill platform data with the default values */
> - pdata->is_private = true;
> - pdata->is_memcpy = true;
> pdata->chan_allocation_order =
> CHAN_ALLOCATION_ASCENDING;
> pdata->chan_priority = CHAN_PRIORITY_ASCENDING;
> } else if (chip->pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS)
> {
> @@ -1486,9 +1496,6 @@ int dw_dma_probe(struct dw_dma_chip *chip)
> goto err_pdata;
> } else {
> memcpy(dw->pdata, chip->pdata, sizeof(*dw->pdata));
> -
> - /* Reassign the platform data pointer */
> - pdata = dw->pdata;
> }
>
> dw->chan = devm_kcalloc(chip->dev, pdata->nr_channels,
> sizeof(*dw->chan),
> @@ -1569,7 +1576,7 @@ int dw_dma_probe(struct dw_dma_chip *chip)
> (dwc_params >> DWC_PARAMS_MBLK_EN &
> 0x1) == 0;
> } else {
> dwc->block_size = pdata->block_size;
> - dwc->nollp = pdata->is_nollp;
> + dwc->nollp = test_bit(QUIRKS_IS_NOLLP,
> &pdata->quirks);
Perhaps you need another patch which actually moves nollp to dwc->flags.
> }
> }
>
> @@ -1582,9 +1589,9 @@ int dw_dma_probe(struct dw_dma_chip *chip)
>
> /* Set capabilities */
> dma_cap_set(DMA_SLAVE, dw->dma.cap_mask);
> - if (pdata->is_private)
> + if (test_bit(QUIRKS_IS_PRIVATE, &pdata->quirks))
> dma_cap_set(DMA_PRIVATE, dw->dma.cap_mask);
> - if (pdata->is_memcpy)
> + if (test_bit(QUIRKS_IS_MEMCPY, &pdata->quirks))
> dma_cap_set(DMA_MEMCPY, dw->dma.cap_mask);
>
> dw->dma.dev = chip->dev;
> diff --git a/drivers/dma/dw/platform.c b/drivers/dma/dw/platform.c
> index 5bda0eb..308b977 100644
> --- a/drivers/dma/dw/platform.c
> +++ b/drivers/dma/dw/platform.c
> @@ -12,6 +12,7 @@
> * published by the Free Software Foundation.
> */
>
> +#include <linux/bitops.h>
> #include <linux/module.h>
> #include <linux/device.h>
> #include <linux/clk.h>
> @@ -111,41 +112,48 @@ dw_dma_parse_dt(struct platform_device *pdev)
> return NULL;
> }
>
> - if (of_property_read_u32(np, "dma-masters", &nr_masters))
> - return NULL;
> - if (nr_masters < 1 || nr_masters > DW_DMA_MAX_NR_MASTERS)
> - return NULL;
> -
> - if (of_property_read_u32(np, "dma-channels", &nr_channels))
> - return NULL;
> -
> pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
> if (!pdata)
> return NULL;
>
> + set_bit(QUIRKS_ONLY_USED, &pdata->quirks);
> +
> + if (of_property_read_bool(np, "is-private"))
> + set_bit(QUIRKS_IS_PRIVATE, &pdata->quirks);
> +
> + if (of_property_read_bool(np, "is-memcpy"))
> + set_bit(QUIRKS_IS_MEMCPY, &pdata->quirks);
> +
> + if (of_property_read_bool(np, "is-nollp"))
> + set_bit(QUIRKS_IS_NOLLP, &pdata->quirks);
I would suggest to convert to unified device property API first.
> +
> + if (of_property_read_u32(np, "dma-masters", &nr_masters))
> + return pdata;
> + if (nr_masters < 1 || nr_masters > DW_DMA_MAX_NR_MASTERS)
> + return pdata;
> +
> pdata->nr_masters = nr_masters;
> - pdata->nr_channels = nr_channels;
>
> - if (of_property_read_bool(np, "is_private"))
> - pdata->is_private = true;
> + if (of_property_read_u32(np, "dma-channels", &nr_channels))
> + return pdata;
>
> - if (!of_property_read_u32(np, "chan_allocation_order", &tmp))
> + pdata->nr_channels = nr_channels;
> +
> + if (!of_property_read_u32(np, "chan-allocation-order", &tmp))
> pdata->chan_allocation_order = (unsigned char)tmp;
>
> - if (!of_property_read_u32(np, "chan_priority", &tmp))
> + if (!of_property_read_u32(np, "chan-priority", &tmp))
> pdata->chan_priority = tmp;
>
> - if (!of_property_read_u32(np, "block_size", &tmp))
> + if (!of_property_read_u32(np, "block-size", &tmp))
> pdata->block_size = tmp;
>
> if (!of_property_read_u32_array(np, "data-width", arr,
> nr_masters)) {
> for (tmp = 0; tmp < nr_masters; tmp++)
> pdata->data_width[tmp] = arr[tmp];
> - } else if (!of_property_read_u32_array(np, "data_width", arr,
> nr_masters)) {
> - for (tmp = 0; tmp < nr_masters; tmp++)
> - pdata->data_width[tmp] = BIT(arr[tmp] &
> 0x07);
> }
>
> + clear_bit(QUIRKS_ONLY_USED, &pdata->quirks);
> return pdata;
> }
> #else
> diff --git a/include/linux/platform_data/dma-dw.h
> b/include/linux/platform_data/dma-dw.h
> index 5f0e11e..9cd8199 100644
> --- a/include/linux/platform_data/dma-dw.h
> +++ b/include/linux/platform_data/dma-dw.h
> @@ -37,10 +37,7 @@ struct dw_dma_slave {
> /**
> * struct dw_dma_platform_data - Controller configuration parameters
> * @nr_channels: Number of channels supported by hardware (max 8)
> - * @is_private: The device channels should be marked as private and
> not for
> - * by the general purpose DMA channel allocator.
> - * @is_memcpy: The device channels do support memory-to-memory
> transfers.
> - * @is_nollp: The device channels does not support multi block
> transfers.
> + * @quirks: Bit field with platform quirks
> * @chan_allocation_order: Allocate channels starting from 0 or 7
> * @chan_priority: Set channel priority increasing from 0 to 7 or 7
> to 0.
> * @block_size: Maximum block size supported by the controller
> @@ -50,9 +47,18 @@ struct dw_dma_slave {
> */
> struct dw_dma_platform_data {
> unsigned int nr_channels;
> - bool is_private;
> - bool is_memcpy;
> - bool is_nollp;
> +/* Only use quirks from platform data structure */
> +#define QUIRKS_ONLY_USED 0
> +/*
> + * The device channels should be marked as private and not for
> + * by the general purpose DMA channel allocator.
> + */
> +#define QUIRKS_IS_PRIVATE 1
> +/* The device channels do support memory-to-memory transfers. */
> +#define QUIRKS_IS_MEMCPY 2
> +/* The device channels do not support multi block transfers. */
> +#define QUIRKS_IS_NOLLP 3
You may move descriptions to above struct description field. It will be
consolidated and moreover visible in kernel-doc processed documents.
> + unsigned long quirks;
> #define CHAN_ALLOCATION_ASCENDING 0 /* zero to seven */
> #define CHAN_ALLOCATION_DESCENDING 1 /* seven to zero
> */
> unsigned char chan_allocation_order;
--
Andy Shevchenko <andriy.shevchenko at linux.intel.com>
Intel Finland Oy
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