Re: [PATCH 2/2] dma: Add Spreadtrum DMA controller driver

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




Hi Baolin,

On 18 July 2017 at 15:06, Baolin Wang <baolin.wang@xxxxxxxxxxxxxx> wrote:
> This patch adds the DMA controller driver for Spreadtrum SC9860 platform.

I guess this driver is not only for SC9860, instead it should work for
all most all Spreadtrum's platforms?

>
> Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxx>
> ---
>  drivers/dma/Kconfig          |    7 +
>  drivers/dma/Makefile         |    1 +
>  drivers/dma/sprd-dma.c       | 1451 ++++++++++++++++++++++++++++++++++++++++++
>  include/linux/dma/sprd-dma.h |  270 ++++++++
>  4 files changed, 1729 insertions(+)
>  create mode 100644 drivers/dma/sprd-dma.c
>  create mode 100644 include/linux/dma/sprd-dma.h
>
> diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
> index fa8f9c0..961f6ea 100644
> --- a/drivers/dma/Kconfig
> +++ b/drivers/dma/Kconfig
> @@ -477,6 +477,13 @@ config STM32_DMA
>           If you have a board based on such a MCU and wish to use DMA say Y
>           here.
>
> +config SPRD_DMA
> +       bool "Spreadtrum DMA support"
> +       depends on ARCH_SPRD
> +       select DMA_ENGINE
> +       help
> +         Enable support for the on-chip DMA controller on Spreadtrum platform.
> +
>  config S3C24XX_DMAC
>         bool "Samsung S3C24XX DMA support"
>         depends on ARCH_S3C24XX || COMPILE_TEST
> diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
> index d12ab29..0fee561 100644
> --- a/drivers/dma/Makefile
> +++ b/drivers/dma/Makefile
> @@ -58,6 +58,7 @@ obj-$(CONFIG_RENESAS_DMA) += sh/
>  obj-$(CONFIG_SIRF_DMA) += sirf-dma.o
>  obj-$(CONFIG_STE_DMA40) += ste_dma40.o ste_dma40_ll.o
>  obj-$(CONFIG_STM32_DMA) += stm32-dma.o
> +obj-$(CONFIG_SPRD_DMA) += sprd-dma.o
>  obj-$(CONFIG_S3C24XX_DMAC) += s3c24xx-dma.o
>  obj-$(CONFIG_TXX9_DMAC) += txx9dmac.o
>  obj-$(CONFIG_TEGRA20_APB_DMA) += tegra20-apb-dma.o
> diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
> new file mode 100644
> index 0000000..64eaef7
> --- /dev/null
> +++ b/drivers/dma/sprd-dma.c
> @@ -0,0 +1,1451 @@
> +/*
> + * Copyright (C) 2017 Spreadtrum Communications Inc.
> + *
> + * This software is licensed under the terms of the GNU General Public
> + * License version 2, as published by the Free Software Foundation, and
> + * may be copied, distributed, and modified under those terms.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +

In order to keep consistent with other Spreadtrum's drivers/ DT files
that had been upstreamed, I suggest to use SPDX-License-Identifier
tag.

Thanks,
Chunyan

> +#include <linux/clk.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/dma/sprd-dma.h>
> +#include <linux/errno.h>
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_dma.h>
> +#include <linux/of_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/slab.h>
> +
> +#include "dmaengine.h"
> +
> +#define SPRD_DMA_DESCRIPTORS           16
> +#define SPRD_DMA_CFG_COUNT             32
> +#define SPRD_DMA_CHN_REG_OFFSET                0x1000
> +#define SPRD_DMA_CHN_REG_LENGTH                0x40
> +#define SPRD_DMA_MEMCPY_MIN_SIZE       64
> +
> +/* DMA global registers definition */
> +#define DMA_GLB_PAUSE                  0x0
> +#define DMA_GLB_FRAG_WAIT              0x4
> +#define DMA_GLB_REQ_PEND0_EN           0x8
> +#define DMA_GLB_REQ_PEND1_EN           0xc
> +#define DMA_GLB_INT_RAW_STS            0x10
> +#define DMA_GLB_INT_MSK_STS            0x14
> +#define DMA_GLB_REQ_STS                        0x18
> +#define DMA_GLB_CHN_EN_STS             0x1c
> +#define DMA_GLB_DEBUG_STS              0x20
> +#define DMA_GLB_ARB_SEL_STS            0x24
> +#define DMA_GLB_CHN_START_CHN_CFG1     0x28
> +#define DMA_GLB_CHN_START_CHN_CFG2     0x2c
> +#define DMA_CHN_LLIST_OFFSET           0x10
> +#define DMA_GLB_REQ_CID(base, uid)     \
> +               ((unsigned long)(base) + 0x2000 + 0x4 * ((uid) - 1))
> +
> +/* DMA_GLB_CHN_START_CHN_CFG register definition */
> +#define SRC_CHN_OFFSET                 0
> +#define DST_CHN_OFFSET                 8
> +#define START_MODE_OFFSET              16
> +#define CHN_START_CHN                  BIT(24)
> +
> +/* DMA channel registers definition */
> +#define DMA_CHN_PAUSE                  0x0
> +#define DMA_CHN_REQ                    0x4
> +#define DMA_CHN_CFG                    0x8
> +#define DMA_CHN_INTC                   0xc
> +#define DMA_CHN_SRC_ADDR               0x10
> +#define DMA_CHN_DES_ADDR               0x14
> +#define DMA_CHN_FRG_LEN                        0x18
> +#define DMA_CHN_BLK_LEN                        0x1c
> +#define DMA_CHN_TRSC_LEN               0x20
> +#define DMA_CHN_TRSF_STEP              0x24
> +#define DMA_CHN_WARP_PTR               0x28
> +#define DMA_CHN_WARP_TO                        0x2c
> +#define DMA_CHN_LLIST_PTR              0x30
> +#define DMA_CHN_FRAG_STEP              0x34
> +#define DMA_CHN_SRC_BLK_STEP           0x38
> +#define DMA_CHN_DES_BLK_STEP           0x3c
> +
> +/* DMA_CHN_INTC register definition */
> +#define DMA_CHN_INT_MASK               GENMASK(4, 0)
> +#define DMA_CHN_INT_CLR_OFFSET         24
> +#define FRAG_INT_EN                    BIT(0)
> +#define BLK_INT_EN                     BIT(1)
> +#define TRANS_INT_EN                   BIT(2)
> +#define LIST_INT_EN                    BIT(3)
> +#define CFG_ERROR_INT_EN               BIT(4)
> +
> +/* DMA_CHN_CFG register definition */
> +#define DMA_CHN_EN                     BIT(0)
> +#define DMA_CHN_PRIORITY_OFFSET                12
> +#define LLIST_EN_OFFSET                        4
> +#define CHN_WAIT_BDONE                 24
> +#define DMA_DONOT_WAIT_BDONE           1
> +
> +/* DMA_CHN_REQ register definition */
> +#define DMA_CHN_REQ_EN                 BIT(0)
> +
> +/* DMA_CHN_PAUSE register definition */
> +#define DMA_CHN_PAUSE_EN               BIT(0)
> +#define DMA_CHN_PAUSE_STS              BIT(2)
> +#define DMA_CHN_PAUSE_CNT              0x2000
> +
> +/* DMA_CHN_WARP_* register definition */
> +#define DMA_CHN_ADDR_MASK              GENMASK(31, 28)
> +#define DMA_CHN_HIGH_ADDR_OFFSET       4
> +#define WRAP_DATA_MASK                 GENMASK(27, 0)
> +
> +/* DMA_CHN_INTC register definition */
> +#define FRAG_INT_STS                   BIT(8)
> +#define BLK_INT_STS                    BIT(9)
> +#define TRSC_INT_STS                   BIT(10)
> +#define LLIST_INT_STS                  BIT(11)
> +#define CFGERR_INT_STS                 BIT(12)
> +
> +/* DMA_CHN_FRG_LEN register definition */
> +#define SRC_DATAWIDTH_OFFSET           30
> +#define DES_DATAWIDTH_OFFSET           28
> +#define SWT_MODE_OFFSET                        26
> +#define REQ_MODE_OFFSET                        24
> +#define REQ_MODE_MASK                  0x3
> +#define ADDR_WRAP_SEL_OFFSET           23
> +#define ADDR_WRAP_EN_OFFSET            22
> +#define ADDR_FIX_SEL_OFFSET            21
> +#define ADDR_FIX_SEL_EN                        20
> +#define LLIST_END_OFFSET               19
> +#define BLK_LEN_REC_H_OFFSET           17
> +#define FRG_LEN_OFFSET                 0
> +#define FRG_LEN_MASK                   GENMASK(16, 0)
> +
> +/* DMA_CHN_BLK_LEN register definition */
> +#define BLK_LEN_MASK                   GENMASK(16, 0)
> +
> +/* DMA_CHN_TRSC_LEN register definition */
> +#define TRSC_LEN_MASK                  GENMASK(27, 0)
> +
> +/* DMA_CHN_TRSF_STEP register definition */
> +#define DEST_TRSF_STEP_OFFSET          16
> +#define SRC_TRSF_STEP_OFFSET           0
> +#define TRSF_STEP_MASK                 GENMASK(15, 0)
> +
> +/* DMA_CHN_FRAG_STEP register definition */
> +#define DEST_FRAG_STEP_OFFSET          16
> +#define SRC_FRAG_STEP_OFFSET           0
> +#define FRAG_STEP_MASK                 GENMASK(15, 0)
> +
> +/* DMA_CHN_SRC_BLK_STEP register definition */
> +#define PTR_HIGH_ADDR_MASK             GENMASK(31, 28)
> +#define PTR_HIGH_ADDR_OFFSET           4
> +
> +enum dma_config_type {
> +       SINGLE_CONFIG,
> +       LINKLIST_CONFIG,
> +};
> +
> +/* dma channel configuration */
> +struct sprd_dma_chn_config {
> +       u32 pause;
> +       u32 req;
> +       u32 cfg;
> +       u32 intc;
> +       u32 src_addr;
> +       u32 des_addr;
> +       u32 frg_len;
> +       u32 blk_len;
> +       u32 trsc_len;
> +       u32 trsf_step;
> +       u32 wrap_ptr;
> +       u32 wrap_to;
> +       u32 llist_ptr;
> +       u32 frg_step;
> +       u32 src_blk_step;
> +       u32 des_blk_step;
> +};
> +
> +/* dma request description */
> +struct sprd_dma_desc {
> +       struct dma_async_tx_descriptor  desc;
> +       struct sprd_dma_chn_config      *chn_config;
> +       struct list_head                node;
> +       enum dma_flags                  dma_flags;
> +       int                             cycle;
> +};
> +
> +/* dma channel description */
> +struct sprd_dma_chn {
> +       struct dma_chan                 chan;
> +       struct list_head                free;
> +       struct list_head                prepared;
> +       struct list_head                queued;
> +       struct list_head                active;
> +       struct list_head                completed;
> +       void __iomem                    *chn_base;
> +       spinlock_t                      chn_lock;
> +       int                             chn_num;
> +       u32                             dev_id;
> +       void                            *dma_desc_configs;
> +       struct sprd_dma_cfg             dma_cfg[SPRD_DMA_CFG_COUNT];
> +       int                             cfg_count;
> +};
> +
> +/* SPRD dma device */
> +struct sprd_dma_dev {
> +       struct dma_device               dma_dev;
> +       void __iomem                    *glb_base;
> +       struct clk                      *clk;
> +       struct clk                      *ashb_clk;
> +       int                             irq;
> +       struct tasklet_struct           tasklet;
> +       struct kmem_cache               *dma_desc_node_cachep;
> +       u32                             total_chns;
> +       struct sprd_dma_chn             channels[0];
> +};
> +
> +static bool sprd_dma_filter_fn(struct dma_chan *chan, void *param);
> +static struct of_dma_filter_info sprd_dma_info = {
> +       .filter_fn = sprd_dma_filter_fn,
> +};
> +
> +static inline struct sprd_dma_chn *to_sprd_dma_chan(struct dma_chan *c)
> +{
> +       return container_of(c, struct sprd_dma_chn, chan);
> +}
> +
> +static inline struct sprd_dma_dev *to_sprd_dma_dev(struct dma_chan *c)
> +{
> +       struct sprd_dma_chn *mchan = to_sprd_dma_chan(c);
> +
> +       return container_of(mchan, struct sprd_dma_dev, channels[c->chan_id]);
> +}
> +
> +static inline struct sprd_dma_desc *
> +to_sprd_dma_desc(struct dma_async_tx_descriptor *tx)
> +{
> +       return container_of(tx, struct sprd_dma_desc, desc);
> +}
> +
> +static int sprd_dma_enable(struct sprd_dma_dev *sdev)
> +{
> +       int ret;
> +
> +       ret = clk_prepare_enable(sdev->clk);
> +       if (ret)
> +               return ret;
> +
> +       if (!IS_ERR(sdev->ashb_clk))
> +               ret = clk_prepare_enable(sdev->ashb_clk);
> +
> +       return ret;
> +}
> +
> +static void sprd_dma_disable(struct sprd_dma_dev *sdev)
> +{
> +       clk_disable_unprepare(sdev->clk);
> +
> +       if (!IS_ERR(sdev->ashb_clk))
> +               clk_disable_unprepare(sdev->ashb_clk);
> +}
> +
> +static void sprd_dma_set_uid(struct sprd_dma_chn *mchan)
> +{
> +       struct sprd_dma_dev *sdev = to_sprd_dma_dev(&mchan->chan);
> +       u32 dev_id = mchan->dev_id;
> +
> +       if (dev_id != DMA_SOFTWARE_UID)
> +               writel(mchan->chn_num + 1, (void __iomem *)DMA_GLB_REQ_CID(
> +                      sdev->glb_base, dev_id));
> +}
> +
> +static void sprd_dma_unset_uid(struct sprd_dma_chn *mchan)
> +{
> +       struct sprd_dma_dev *sdev = to_sprd_dma_dev(&mchan->chan);
> +       u32 dev_id = mchan->dev_id;
> +
> +       if (dev_id != DMA_SOFTWARE_UID)
> +               writel(0, (void __iomem *)DMA_GLB_REQ_CID(sdev->glb_base,
> +                      dev_id));
> +}
> +
> +static void sprd_dma_clear_int(struct sprd_dma_chn *mchan)
> +{
> +       u32 intc = readl(mchan->chn_base + DMA_CHN_INTC);
> +
> +       intc |= DMA_CHN_INT_MASK << DMA_CHN_INT_CLR_OFFSET;
> +       writel(intc, mchan->chn_base + DMA_CHN_INTC);
> +}
> +
> +static void sprd_dma_enable_chn(struct sprd_dma_chn *mchan)
> +{
> +       u32 cfg = readl(mchan->chn_base + DMA_CHN_CFG);
> +
> +       cfg |= DMA_CHN_EN;
> +       writel(cfg, mchan->chn_base + DMA_CHN_CFG);
> +}
> +
> +static void sprd_dma_disable_chn(struct sprd_dma_chn *mchan)
> +{
> +       u32 cfg = readl(mchan->chn_base + DMA_CHN_CFG);
> +
> +       cfg &= ~DMA_CHN_EN;
> +       writel(cfg, mchan->chn_base + DMA_CHN_CFG);
> +}
> +
> +static void sprd_dma_soft_request(struct sprd_dma_chn *mchan)
> +{
> +       u32 req = readl(mchan->chn_base + DMA_CHN_REQ);
> +
> +       req |= DMA_CHN_REQ_EN;
> +       writel(req, mchan->chn_base + DMA_CHN_REQ);
> +}
> +
> +static void sprd_dma_stop_and_disable(struct sprd_dma_chn *mchan)
> +{
> +       u32 cfg = readl(mchan->chn_base + DMA_CHN_CFG);
> +       u32 pause, timeout = DMA_CHN_PAUSE_CNT;
> +
> +       if (!(cfg & DMA_CHN_EN))
> +               return;
> +
> +       pause = readl(mchan->chn_base + DMA_CHN_PAUSE);
> +       pause |= DMA_CHN_PAUSE_EN;
> +       writel(pause, mchan->chn_base + DMA_CHN_PAUSE);
> +
> +       do {
> +               pause = readl(mchan->chn_base + DMA_CHN_PAUSE);
> +               if (pause & DMA_CHN_PAUSE_STS)
> +                       break;
> +
> +               cpu_relax();
> +       } while (--timeout > 0);
> +
> +       sprd_dma_disable_chn(mchan);
> +       writel(0, mchan->chn_base + DMA_CHN_PAUSE);
> +}
> +
> +static unsigned long sprd_dma_get_dst_addr(struct sprd_dma_chn *mchan)
> +{
> +       unsigned long addr;
> +
> +       addr = readl(mchan->chn_base + DMA_CHN_DES_ADDR);
> +       addr |= (readl(mchan->chn_base + DMA_CHN_WARP_TO) &
> +                DMA_CHN_ADDR_MASK) << DMA_CHN_HIGH_ADDR_OFFSET;
> +       return addr;
> +}
> +
> +static enum dma_int_type sprd_dma_get_int_type(struct sprd_dma_chn *mchan)
> +{
> +       u32 intc_reg = readl(mchan->chn_base + DMA_CHN_INTC);
> +
> +       if (intc_reg & CFGERR_INT_STS)
> +               return CONFIG_ERR;
> +       else if (intc_reg & LLIST_INT_STS)
> +               return LIST_DONE;
> +       else if (intc_reg & TRSC_INT_STS)
> +               return TRANS_DONE;
> +       else if (intc_reg & BLK_INT_STS)
> +               return BLK_DONE;
> +       else if (intc_reg & FRAG_INT_STS)
> +               return FRAG_DONE;
> +       else
> +               return NO_INT;
> +}
> +
> +static enum dma_request_mode sprd_dma_get_req_type(struct sprd_dma_chn *mchan)
> +{
> +       u32 frag_reg = readl(mchan->chn_base + DMA_CHN_FRG_LEN);
> +
> +       switch ((frag_reg >> REQ_MODE_OFFSET) & REQ_MODE_MASK) {
> +       case 0:
> +               return FRAG_REQ_MODE;
> +       case 1:
> +               return BLOCK_REQ_MODE;
> +       case 2:
> +               return TRANS_REQ_MODE;
> +       case 3:
> +               return LIST_REQ_MODE;
> +       default:
> +               return FRAG_REQ_MODE;
> +       }
> +}
> +
> +static int sprd_dma_chn_start_chn(struct sprd_dma_chn *mchan,
> +                                 struct sprd_dma_desc *mdesc)
> +{
> +       struct sprd_dma_dev *sdev = to_sprd_dma_dev(&mchan->chan);
> +       enum dma_flags flag = mdesc->dma_flags;
> +       int chn = mchan->chn_num + 1;
> +       unsigned int cfg_group1, cfg_group2, start_mode = 0;
> +
> +       if (!(flag & (DMA_GROUP1_SRC | DMA_GROUP2_SRC | DMA_GROUP1_DST |
> +                     DMA_GROUP2_DST)))
> +               return 0;
> +
> +       if (flag & (DMA_GROUP1_SRC | DMA_GROUP2_SRC)) {
> +               switch (flag & (DMA_MUTL_FRAG_DONE | DMA_MUTL_BLK_DONE |
> +                       DMA_MUTL_TRANS_DONE | DMA_MUTL_LIST_DONE)) {
> +               case DMA_MUTL_FRAG_DONE:
> +                       start_mode = 0;
> +                       break;
> +               case DMA_MUTL_BLK_DONE:
> +                       start_mode = 1;
> +                       break;
> +               case DMA_MUTL_TRANS_DONE:
> +                       start_mode = 2;
> +                       break;
> +               case DMA_MUTL_LIST_DONE:
> +                       start_mode = 3;
> +                       break;
> +               default:
> +                       dev_err(sdev->dma_dev.dev,
> +                               "chn stat chn mode incorrect\n");
> +                       return -EINVAL;
> +               }
> +       }
> +
> +       cfg_group1 = readl(sdev->glb_base + DMA_GLB_CHN_START_CHN_CFG1);
> +       cfg_group2 = readl(sdev->glb_base + DMA_GLB_CHN_START_CHN_CFG2);
> +
> +       switch (flag & (DMA_GROUP1_SRC | DMA_GROUP2_SRC |
> +               DMA_GROUP1_DST | DMA_GROUP2_DST)) {
> +       case DMA_GROUP1_SRC:
> +               cfg_group1 |= chn << SRC_CHN_OFFSET;
> +               cfg_group1 |= (1 << start_mode) << START_MODE_OFFSET;
> +               cfg_group1 |= CHN_START_CHN;
> +               writel(cfg_group1, sdev->glb_base + DMA_GLB_CHN_START_CHN_CFG1);
> +               break;
> +       case DMA_GROUP2_SRC:
> +               cfg_group2 |= chn << SRC_CHN_OFFSET;
> +               cfg_group2 |= (1 << start_mode) << START_MODE_OFFSET;
> +               cfg_group2 |= CHN_START_CHN;
> +               writel(cfg_group2, sdev->glb_base + DMA_GLB_CHN_START_CHN_CFG2);
> +               break;
> +       case DMA_GROUP1_DST:
> +               cfg_group1 |= chn << DST_CHN_OFFSET;
> +               cfg_group1 |= CHN_START_CHN;
> +               writel(cfg_group1, sdev->glb_base + DMA_GLB_CHN_START_CHN_CFG1);
> +               break;
> +       case DMA_GROUP2_DST:
> +               cfg_group2 |= chn << DST_CHN_OFFSET;
> +               cfg_group2 |= CHN_START_CHN;
> +               writel(cfg_group2, sdev->glb_base + DMA_GLB_CHN_START_CHN_CFG2);
> +               break;
> +       default:
> +               break;
> +       }
> +
> +       return 0;
> +}
> +
> +static int sprd_dma_set_chn_config(struct sprd_dma_chn *mchan,
> +                                  struct sprd_dma_desc *mdesc)
> +{
> +       struct sprd_dma_chn_config *cfg = mdesc->chn_config;
> +       int ret;
> +
> +       ret = sprd_dma_chn_start_chn(mchan, mdesc);
> +       if (ret)
> +               return ret;
> +
> +       writel(cfg->pause, mchan->chn_base + DMA_CHN_PAUSE);
> +       writel(cfg->cfg, mchan->chn_base + DMA_CHN_CFG);
> +       writel(cfg->intc, mchan->chn_base + DMA_CHN_INTC);
> +       writel(cfg->src_addr, mchan->chn_base + DMA_CHN_SRC_ADDR);
> +       writel(cfg->des_addr, mchan->chn_base + DMA_CHN_DES_ADDR);
> +       writel(cfg->frg_len, mchan->chn_base + DMA_CHN_FRG_LEN);
> +       writel(cfg->blk_len, mchan->chn_base + DMA_CHN_BLK_LEN);
> +       writel(cfg->trsc_len, mchan->chn_base + DMA_CHN_TRSC_LEN);
> +       writel(cfg->trsf_step, mchan->chn_base + DMA_CHN_TRSF_STEP);
> +       writel(cfg->wrap_ptr, mchan->chn_base + DMA_CHN_WARP_PTR);
> +       writel(cfg->wrap_to, mchan->chn_base + DMA_CHN_WARP_TO);
> +       writel(cfg->llist_ptr, mchan->chn_base + DMA_CHN_LLIST_PTR);
> +       writel(cfg->frg_step, mchan->chn_base + DMA_CHN_FRAG_STEP);
> +       writel(cfg->src_blk_step, mchan->chn_base + DMA_CHN_SRC_BLK_STEP);
> +       writel(cfg->des_blk_step, mchan->chn_base + DMA_CHN_DES_BLK_STEP);
> +       writel(cfg->req, mchan->chn_base + DMA_CHN_REQ);
> +
> +       return 0;
> +}
> +
> +static int sprd_dma_start(struct sprd_dma_chn *mchan)
> +{
> +       struct sprd_dma_desc *first;
> +       int ret;
> +
> +       if (list_empty(&mchan->active))
> +               return 0;
> +
> +       /*
> +        * Get the first DMA descriptor from active list, and copy the DMA
> +        * configuration from DMA descriptor to this DMA channel.
> +        */
> +       first = list_first_entry(&mchan->active, struct sprd_dma_desc, node);
> +       ret = sprd_dma_set_chn_config(mchan, first);
> +       if (ret)
> +               return ret;
> +
> +       sprd_dma_set_uid(mchan);
> +       sprd_dma_enable_chn(mchan);
> +
> +       if (mchan->dev_id == DMA_SOFTWARE_UID &&
> +           !(first->dma_flags & (DMA_GROUP1_DST | DMA_GROUP2_DST)))
> +               sprd_dma_soft_request(mchan);
> +
> +       return 0;
> +}
> +
> +static void sprd_dma_stop(struct sprd_dma_chn *mchan)
> +{
> +       sprd_dma_unset_uid(mchan);
> +       sprd_dma_stop_and_disable(mchan);
> +       sprd_dma_clear_int(mchan);
> +}
> +
> +static int sprd_dma_process_completed(struct sprd_dma_dev *sdev)
> +{
> +       struct sprd_dma_chn *mchan;
> +       struct sprd_dma_desc *mdesc;
> +       struct sprd_dma_desc *first;
> +       struct dma_async_tx_descriptor *desc;
> +       u32 dma_total_chns = sdev->total_chns;
> +       dma_cookie_t last_cookie = 0;
> +       unsigned long flags;
> +       LIST_HEAD(list);
> +       int i;
> +
> +       for (i = 0; i < dma_total_chns; i++) {
> +               mchan = &sdev->channels[i];
> +
> +               spin_lock_irqsave(&mchan->chn_lock, flags);
> +               if (!list_empty(&mchan->completed))
> +                       list_splice_tail_init(&mchan->completed, &list);
> +               spin_unlock_irqrestore(&mchan->chn_lock, flags);
> +
> +               if (list_empty(&list))
> +                       continue;
> +
> +               list_for_each_entry(mdesc, &list, node) {
> +                       desc = &mdesc->desc;
> +
> +                       if (desc->callback)
> +                               desc->callback(desc->callback_param);
> +
> +                       dma_run_dependencies(desc);
> +                       last_cookie = desc->cookie;
> +               }
> +
> +               spin_lock_irqsave(&mchan->chn_lock, flags);
> +               list_splice_tail_init(&list, &mchan->free);
> +
> +               /*
> +                * Check if there are pending DMA descriptor in queued list
> +                * need to be queued.
> +                */
> +               if (!list_empty(&mchan->queued)) {
> +                       list_for_each_entry(mdesc, &mchan->queued, node) {
> +                               /*
> +                                * If the DMA descriptor flag is set
> +                                * DMA_GROUP1_DST or DMA_GROUP1_DST flag, which
> +                                * means this DMA descriptor do not need to be
> +                                * activated and it will be invoked by another
> +                                * DMA descriptor which set DMA_GROUP1_SRC or
> +                                * DMA_GROUP2_SRC flag.
> +                                */
> +                               if (!(mdesc->dma_flags &
> +                                     (DMA_GROUP1_DST | DMA_GROUP2_DST)) &&
> +                                   list_empty(&mchan->active)) {
> +                                       first = list_first_entry(&mchan->queued,
> +                                               struct sprd_dma_desc, node);
> +                                       list_move_tail(&first->node,
> +                                                      &mchan->active);
> +                                       sprd_dma_start(mchan);
> +                                       break;
> +                               }
> +                       }
> +               } else {
> +                       mchan->chan.completed_cookie = last_cookie;
> +               }
> +
> +               spin_unlock_irqrestore(&mchan->chn_lock, flags);
> +       }
> +
> +       return 0;
> +}
> +
> +static void sprd_dma_tasklet(unsigned long data)
> +{
> +       struct sprd_dma_dev *sdev = (void *)data;
> +
> +       sprd_dma_process_completed(sdev);
> +}
> +
> +static bool sprd_dma_check_trans_done(struct sprd_dma_desc *mdesc,
> +                                     enum dma_int_type int_type,
> +                                     enum dma_request_mode req_mode)
> +{
> +       if (mdesc->cycle == 1)
> +               return false;
> +
> +       if ((unsigned int)int_type >= ((unsigned int)req_mode + 1))
> +               return true;
> +       else
> +               return false;
> +}
> +
> +static irqreturn_t dma_irq_handle(int irq, void *dev_id)
> +{
> +       struct sprd_dma_dev *sdev = (struct sprd_dma_dev *)dev_id;
> +       u32 irq_status = readl(sdev->glb_base + DMA_GLB_INT_MSK_STS);
> +       struct sprd_dma_chn *mchan;
> +       struct sprd_dma_desc *mdesc;
> +       struct dma_async_tx_descriptor *desc;
> +       enum dma_request_mode req_type;
> +       enum dma_int_type int_type;
> +       bool trans_done = false;
> +       u32 i;
> +
> +       while (irq_status) {
> +               i = __ffs(irq_status);
> +               irq_status &= (irq_status - 1);
> +               mchan = &sdev->channels[i];
> +
> +               spin_lock(&mchan->chn_lock);
> +               int_type = sprd_dma_get_int_type(mchan);
> +               req_type = sprd_dma_get_req_type(mchan);
> +               sprd_dma_clear_int(mchan);
> +
> +               if (!list_empty(&mchan->active)) {
> +                       mdesc = list_first_entry(&mchan->active,
> +                                                struct sprd_dma_desc, node);
> +                       /*
> +                        * Check if the dma request descriptor is done, if it
> +                        * is done we should move this descriptor into
> +                        * complete list to handle.
> +                        */
> +                       trans_done = sprd_dma_check_trans_done(mdesc, int_type,
> +                                                              req_type);
> +                       if (trans_done == true)
> +                               list_splice_tail_init(&mchan->active,
> +                                                     &mchan->completed);
> +                       /*
> +                        * If the cycle is 1, which means this DMA descriptor
> +                        * will always in active state until user free this DMA
> +                        * channel's resources. But user may need to be notified
> +                        * when transfer interrupt is generated.
> +                        */
> +                       if (mdesc->cycle == 1) {
> +                               desc = &mdesc->desc;
> +                               spin_unlock(&mchan->chn_lock);
> +                               if (desc->callback)
> +                                       desc->callback(desc->callback_param);
> +                               continue;
> +                       }
> +               }
> +               spin_unlock(&mchan->chn_lock);
> +       }
> +
> +       tasklet_schedule(&sdev->tasklet);
> +       return IRQ_HANDLED;
> +}
> +
> +static dma_cookie_t sprd_desc_submit(struct dma_async_tx_descriptor *tx)
> +{
> +       struct sprd_dma_chn *mchan = to_sprd_dma_chan(tx->chan);
> +       struct sprd_dma_desc *mdesc = to_sprd_dma_desc(tx);
> +       struct sprd_dma_desc *first;
> +       unsigned long flags;
> +       dma_cookie_t cookie;
> +       int ret;
> +
> +       spin_lock_irqsave(&mchan->chn_lock, flags);
> +       cookie = dma_cookie_assign(tx);
> +       list_move_tail(&mdesc->node, &mchan->queued);
> +
> +       /*
> +        * If we set DMA_GROUP1_DST or DMA_GROUP2_DST flags, which means we do
> +        * not need start this DMA transfer and it will be invoked by other DMA
> +        * transfer setting DMA_GROUP1_SRC or DMA_GROUP2_SRC flag.
> +        */
> +       if (mdesc->dma_flags & (DMA_GROUP1_DST | DMA_GROUP2_DST)) {
> +               ret = sprd_dma_set_chn_config(mchan, mdesc);
> +               if (ret) {
> +                       spin_unlock_irqrestore(&mchan->chn_lock, flags);
> +                       return ret;
> +               }
> +
> +               sprd_dma_enable_chn(mchan);
> +       } else if (list_empty(&mchan->active)) {
> +               first = list_first_entry(&mchan->queued, struct sprd_dma_desc,
> +                                        node);
> +               list_move_tail(&first->node, &mchan->active);
> +               ret = sprd_dma_start(mchan);
> +               if (ret)
> +                       cookie = ret;
> +       }
> +       spin_unlock_irqrestore(&mchan->chn_lock, flags);
> +
> +       return cookie;
> +}
> +
> +static int sprd_dma_alloc_chan_resources(struct dma_chan *chan)
> +{
> +       struct sprd_dma_chn *mchan = to_sprd_dma_chan(chan);
> +       struct sprd_dma_dev *sdev = to_sprd_dma_dev(chan);
> +       struct sprd_dma_desc *mdesc, *tmp;
> +       struct sprd_dma_chn_config *chn_configs;
> +       LIST_HEAD(descs);
> +       unsigned long flags;
> +       int ret, i;
> +
> +       ret = pm_runtime_get_sync(chan->device->dev);
> +       if (ret < 0) {
> +               dev_err(sdev->dma_dev.dev, "pm runtime get failed: %d\n", ret);
> +               return ret;
> +       }
> +
> +       chn_configs = devm_kzalloc(sdev->dma_dev.dev,
> +                              SPRD_DMA_DESCRIPTORS *
> +                              sizeof(struct sprd_dma_chn_config),
> +                              GFP_KERNEL);
> +       if (!chn_configs) {
> +               ret = -ENOMEM;
> +               goto err_alloc;
> +       }
> +
> +       for (i = 0; i < SPRD_DMA_DESCRIPTORS; i++) {
> +               mdesc = (struct sprd_dma_desc *)kmem_cache_zalloc(
> +                                       sdev->dma_desc_node_cachep,
> +                                       GFP_ATOMIC);
> +               if (!mdesc) {
> +                       ret = -ENOMEM;
> +                       goto err_cache_alloc;
> +               }
> +
> +               dma_async_tx_descriptor_init(&mdesc->desc, chan);
> +               mdesc->desc.flags = DMA_CTRL_ACK;
> +               mdesc->desc.tx_submit = sprd_desc_submit;
> +               mdesc->chn_config = &chn_configs[i];
> +               mdesc->cycle = 0;
> +               mdesc->dma_flags = 0;
> +               INIT_LIST_HEAD(&mdesc->node);
> +               list_add_tail(&mdesc->node, &descs);
> +       }
> +
> +       spin_lock_irqsave(&mchan->chn_lock, flags);
> +       list_splice_tail_init(&descs, &mchan->free);
> +       spin_unlock_irqrestore(&mchan->chn_lock, flags);
> +
> +       mchan->dma_desc_configs = chn_configs;
> +       mchan->dev_id = 0;
> +       mchan->cfg_count = 0;
> +       memset(mchan->dma_cfg, 0, sizeof(struct sprd_dma_cfg) *
> +              SPRD_DMA_CFG_COUNT);
> +
> +       return 0;
> +
> +err_cache_alloc:
> +       list_for_each_entry_safe(mdesc, tmp, &descs, node)
> +               kmem_cache_free(sdev->dma_desc_node_cachep, mdesc);
> +       devm_kfree(sdev->dma_dev.dev, chn_configs);
> +err_alloc:
> +       pm_runtime_put_sync(chan->device->dev);
> +       return ret;
> +}
> +
> +static void sprd_dma_free_chan_resources(struct dma_chan *chan)
> +{
> +       struct sprd_dma_chn *mchan = to_sprd_dma_chan(chan);
> +       struct sprd_dma_dev *sdev = to_sprd_dma_dev(chan);
> +       struct sprd_dma_desc *mdesc, *tmp;
> +       unsigned long flags;
> +       LIST_HEAD(descs);
> +
> +       spin_lock_irqsave(&mchan->chn_lock, flags);
> +       list_splice_tail_init(&mchan->prepared, &mchan->free);
> +       list_splice_tail_init(&mchan->queued, &mchan->free);
> +       list_splice_tail_init(&mchan->active, &mchan->free);
> +       list_splice_tail_init(&mchan->completed, &mchan->free);
> +       list_splice_tail_init(&mchan->free, &descs);
> +       spin_unlock_irqrestore(&mchan->chn_lock, flags);
> +
> +       list_for_each_entry_safe(mdesc, tmp, &descs, node)
> +               kmem_cache_free(sdev->dma_desc_node_cachep, mdesc);
> +       devm_kfree(sdev->dma_dev.dev, mchan->dma_desc_configs);
> +
> +       spin_lock_irqsave(&mchan->chn_lock, flags);
> +       sprd_dma_stop(mchan);
> +       spin_unlock_irqrestore(&mchan->chn_lock, flags);
> +
> +       pm_runtime_put_sync(chan->device->dev);
> +}
> +
> +static enum dma_status sprd_dma_tx_status(struct dma_chan *chan,
> +                                         dma_cookie_t cookie,
> +                                         struct dma_tx_state *txstate)
> +{
> +       struct sprd_dma_chn *mchan = to_sprd_dma_chan(chan);
> +       unsigned long flags;
> +       enum dma_status ret;
> +
> +       ret = dma_cookie_status(chan, cookie, txstate);
> +
> +       spin_lock_irqsave(&mchan->chn_lock, flags);
> +       txstate->residue = sprd_dma_get_dst_addr(mchan);
> +       spin_unlock_irqrestore(&mchan->chn_lock, flags);
> +
> +       return ret;
> +}
> +
> +static void sprd_dma_issue_pending(struct dma_chan *chan)
> +{
> +       /*
> +        * We are posting descriptors to the hardware as soon as
> +        * they are ready, so this function does nothing.
> +        */
> +}
> +
> +static int sprd_dma_config(struct dma_chan *chan, struct sprd_dma_desc *mdesc,
> +                          struct sprd_dma_cfg *cfg_list,
> +                          struct sprd_dma_chn_config *chn_config,
> +                          enum dma_config_type type)
> +{
> +       struct sprd_dma_chn *mchan = to_sprd_dma_chan(chan);
> +       struct sprd_dma_dev *sdev = to_sprd_dma_dev(&mchan->chan);
> +       struct sprd_dma_cfg *cfg = cfg_list;
> +       struct sprd_dma_chn_config *dma_chn_config;
> +       static unsigned long first_link_p;
> +       unsigned long linklist_ptr = 0;
> +       u32 fix_mode = 0, fix_en = 0;
> +       u32 wrap_en = 0, wrap_mode = 0;
> +       u32 llist_en = 0, list_end = 0;
> +
> +       if (!IS_ALIGNED(cfg->src_step, 1 << cfg->datawidth)) {
> +               dev_err(sdev->dma_dev.dev, "source step is not aligned\n");
> +               return -EINVAL;
> +       }
> +
> +       if (!IS_ALIGNED(cfg->des_step, 1 << cfg->datawidth)) {
> +               dev_err(sdev->dma_dev.dev, "destination step is not aligned\n");
> +               return -EINVAL;
> +       }
> +
> +       if (type == SINGLE_CONFIG)
> +               dma_chn_config = mdesc->chn_config;
> +       else if (type == LINKLIST_CONFIG)
> +               dma_chn_config = chn_config;
> +       else {
> +               dev_err(sdev->dma_dev.dev,
> +                       "check configuration type failed %d\n", type);
> +               return -EINVAL;
> +       }
> +
> +       if (!mchan->dev_id)
> +               mchan->dev_id = cfg->dev_id;
> +
> +       dma_chn_config->pause = 0;
> +       dma_chn_config->req = 0;
> +
> +       if (cfg->link_cfg_p)
> +               llist_en = 1;
> +
> +       dma_chn_config->cfg = cfg->chn_pri << DMA_CHN_PRIORITY_OFFSET |
> +           llist_en << LLIST_EN_OFFSET |
> +           DMA_DONOT_WAIT_BDONE << CHN_WAIT_BDONE;
> +
> +       if (cfg->wrap_ptr && cfg->wrap_to) {
> +               wrap_en = 1;
> +               dma_chn_config->wrap_ptr = cfg->wrap_ptr & WRAP_DATA_MASK;
> +               dma_chn_config->wrap_to = cfg->wrap_to & WRAP_DATA_MASK;
> +       }
> +
> +       dma_chn_config->wrap_ptr |=
> +               (u32)((cfg->src_addr >> DMA_CHN_HIGH_ADDR_OFFSET) &
> +                     DMA_CHN_ADDR_MASK);
> +       dma_chn_config->wrap_to |=
> +               (u32)((cfg->des_addr >> DMA_CHN_HIGH_ADDR_OFFSET) &
> +                     DMA_CHN_ADDR_MASK);
> +
> +       dma_chn_config->src_addr = (u32)cfg->src_addr;
> +       dma_chn_config->des_addr = (u32)cfg->des_addr;
> +
> +       if ((cfg->src_step != 0 && cfg->des_step != 0) ||
> +           ((cfg->src_step | cfg->des_step) == 0)) {
> +               fix_en = 0;
> +       } else {
> +               fix_en = 1;
> +               if (cfg->src_step)
> +                       fix_mode = 1;
> +               else
> +                       fix_mode = 0;
> +       }
> +
> +       if (wrap_en == 1) {
> +               if (cfg->wrap_to == cfg->src_addr) {
> +                       wrap_mode = 0;
> +               } else if (cfg->wrap_to == cfg->des_addr) {
> +                       wrap_mode = 1;
> +               } else {
> +                       dev_err(sdev->dma_dev.dev,
> +                               "check wrap config failed\n");
> +                       return -EINVAL;
> +               }
> +       }
> +
> +       if (llist_en == 1 && cfg->is_end == DMA_END)
> +               list_end = 1;
> +
> +       dma_chn_config->frg_len = (cfg->datawidth << SRC_DATAWIDTH_OFFSET) |
> +               (cfg->datawidth << DES_DATAWIDTH_OFFSET) |
> +               (cfg->swt_mode << SWT_MODE_OFFSET) |
> +               (cfg->req_mode << REQ_MODE_OFFSET) |
> +               (wrap_mode << ADDR_WRAP_SEL_OFFSET) |
> +               (wrap_en << ADDR_WRAP_EN_OFFSET) |
> +               (fix_mode << ADDR_FIX_SEL_OFFSET) |
> +               (fix_en << ADDR_FIX_SEL_EN) |
> +               (list_end << LLIST_END_OFFSET) |
> +               (cfg->fragmens_len & FRG_LEN_MASK);
> +
> +       dma_chn_config->blk_len = cfg->block_len & BLK_LEN_MASK;
> +
> +       if (type == SINGLE_CONFIG) {
> +               dma_chn_config->intc &= ~DMA_CHN_INT_MASK;
> +               dma_chn_config->intc |= CFG_ERROR_INT_EN;
> +
> +               switch (cfg->irq_mode) {
> +               case NO_INT:
> +                       break;
> +               case FRAG_DONE:
> +                       dma_chn_config->intc |= FRAG_INT_EN;
> +                       break;
> +               case BLK_DONE:
> +                       dma_chn_config->intc |= BLK_INT_EN;
> +                       break;
> +               case BLOCK_FRAG_DONE:
> +                       dma_chn_config->intc |= BLK_INT_EN | FRAG_INT_EN;
> +                       break;
> +               case TRANS_DONE:
> +                       dma_chn_config->intc |= TRANS_INT_EN;
> +                       break;
> +               case TRANS_FRAG_DONE:
> +                       dma_chn_config->intc |= TRANS_INT_EN | FRAG_INT_EN;
> +                       break;
> +               case TRANS_BLOCK_DONE:
> +                       dma_chn_config->intc |= TRANS_INT_EN | BLK_INT_EN;
> +                       break;
> +               case LIST_DONE:
> +                       dma_chn_config->intc |= LIST_INT_EN;
> +                       break;
> +               case CONFIG_ERR:
> +                       dma_chn_config->intc |= CFG_ERROR_INT_EN;
> +                       break;
> +               default:
> +                       dev_err(sdev->dma_dev.dev, "irq mode failed\n");
> +                       return -EINVAL;
> +               }
> +       } else {
> +               dma_chn_config->intc = 0;
> +       }
> +
> +       if (cfg->transcation_len == 0)
> +               dma_chn_config->trsc_len = cfg->block_len & TRSC_LEN_MASK;
> +       else
> +               dma_chn_config->trsc_len = cfg->transcation_len &
> +                       TRSC_LEN_MASK;
> +
> +       dma_chn_config->trsf_step = (cfg->des_step & TRSF_STEP_MASK) <<
> +               DEST_TRSF_STEP_OFFSET |
> +               (cfg->src_step & TRSF_STEP_MASK) << SRC_TRSF_STEP_OFFSET;
> +
> +       dma_chn_config->frg_step = (cfg->dst_frag_step & FRAG_STEP_MASK)
> +               << DEST_FRAG_STEP_OFFSET |
> +               (cfg->src_frag_step & FRAG_STEP_MASK)
> +               << SRC_FRAG_STEP_OFFSET;
> +
> +       dma_chn_config->src_blk_step = cfg->src_blk_step;
> +       dma_chn_config->des_blk_step = cfg->dst_blk_step;
> +
> +       if (first_link_p == 0)
> +               first_link_p = cfg->link_cfg_p;
> +
> +       if (type == SINGLE_CONFIG) {
> +               linklist_ptr = first_link_p + DMA_CHN_LLIST_OFFSET;
> +               first_link_p = 0;
> +       } else if (type == LINKLIST_CONFIG) {
> +               if (cfg->is_end == DMA_LINK)
> +                       linklist_ptr = first_link_p + DMA_CHN_LLIST_OFFSET;
> +               else
> +                       linklist_ptr = cfg->link_cfg_p +
> +                               sizeof(struct sprd_dma_chn_config) +
> +                               DMA_CHN_LLIST_OFFSET;
> +       }
> +
> +       dma_chn_config->src_blk_step |=
> +               (u32)((linklist_ptr >> PTR_HIGH_ADDR_OFFSET) &
> +                     PTR_HIGH_ADDR_MASK);
> +       dma_chn_config->llist_ptr = (u32)linklist_ptr;
> +       return 0;
> +}
> +
> +static int sprd_dma_config_linklist(struct dma_chan *chan,
> +                                   struct sprd_dma_desc *mdesc,
> +                                   struct sprd_dma_cfg *cfg_list,
> +                                   u32 node_size)
> +{
> +       struct sprd_dma_dev *sdev = to_sprd_dma_dev(chan);
> +       struct sprd_dma_chn_config *chn_config_list_v;
> +       struct sprd_dma_cfg start_list;
> +       int ret, i;
> +
> +       chn_config_list_v = (struct sprd_dma_chn_config *)cfg_list[0].link_cfg_v;
> +
> +       for (i = 0; i < node_size; i++) {
> +               if (cfg_list[i].link_cfg_v == 0 || cfg_list[i].link_cfg_p == 0) {
> +                       dev_err(sdev->dma_dev.dev,
> +                               "no allocated memory for list node\n");
> +                       return -EINVAL;
> +               }
> +
> +               ret = sprd_dma_config(chan, NULL, cfg_list + i,
> +                                     chn_config_list_v + i,
> +                                     LINKLIST_CONFIG);
> +               if (ret < 0) {
> +                       dev_err(sdev->dma_dev.dev,
> +                               "linklist configuration failed\n");
> +                       return ret;
> +               }
> +       }
> +
> +       memset((void *)&start_list, 0, sizeof(struct sprd_dma_cfg));
> +       start_list.link_cfg_p = cfg_list[0].link_cfg_p;
> +       start_list.irq_mode = cfg_list[0].irq_mode;
> +       start_list.src_addr = cfg_list[0].src_addr;
> +       start_list.des_addr = cfg_list[0].des_addr;
> +
> +       if (cfg_list[node_size - 1].is_end == DMA_LINK)
> +               mdesc->cycle = 1;
> +
> +       return sprd_dma_config(chan, mdesc, &start_list, NULL, SINGLE_CONFIG);
> +}
> +
> +struct dma_async_tx_descriptor *sprd_dma_prep_dma_memcpy(struct dma_chan *chan,
> +                                                        dma_addr_t dest,
> +                                                        dma_addr_t src,
> +                                                        size_t len,
> +                                                        unsigned long flags)
> +{
> +       struct sprd_dma_dev *sdev = to_sprd_dma_dev(chan);
> +       struct sprd_dma_chn *mchan = to_sprd_dma_chan(chan);
> +       struct sprd_dma_desc *mdesc = NULL;
> +       struct sprd_dma_cfg dma_cfg;
> +       u32 datawidth, src_step, des_step;
> +       int cfg_count = mchan->cfg_count;
> +       unsigned long irq_flags;
> +       int ret;
> +
> +       /*
> +        * If user did not have configuration for DMA transfer, then we should
> +        * configure the DMA controller as default configuration.
> +        */
> +       if (cfg_count == 0) {
> +               if (IS_ALIGNED(len, 4)) {
> +                       datawidth = 2;
> +                       src_step = 4;
> +                       des_step = 4;
> +               } else if (IS_ALIGNED(len, 2)) {
> +                       datawidth = 1;
> +                       src_step = 2;
> +                       des_step = 2;
> +               } else {
> +                       datawidth = 0;
> +                       src_step = 1;
> +                       des_step = 1;
> +               }
> +
> +               memset(&dma_cfg, 0, sizeof(struct sprd_dma_cfg));
> +               dma_cfg.src_addr = src;
> +               dma_cfg.des_addr = dest;
> +               dma_cfg.datawidth = datawidth;
> +               dma_cfg.src_step = src_step;
> +               dma_cfg.des_step = src_step;
> +               dma_cfg.fragmens_len = SPRD_DMA_MEMCPY_MIN_SIZE;
> +               if (len <= BLK_LEN_MASK) {
> +                       dma_cfg.block_len = len;
> +                       dma_cfg.req_mode = BLOCK_REQ_MODE;
> +                       dma_cfg.irq_mode = BLK_DONE;
> +               } else {
> +                       dma_cfg.block_len = SPRD_DMA_MEMCPY_MIN_SIZE;
> +                       dma_cfg.transcation_len = len;
> +                       dma_cfg.req_mode = TRANS_REQ_MODE;
> +                       dma_cfg.irq_mode = TRANS_DONE;
> +               }
> +               cfg_count = 1;
> +       } else if (cfg_count == 1) {
> +               memcpy(&dma_cfg, mchan->dma_cfg, sizeof(struct sprd_dma_cfg));
> +       }
> +
> +       /* get one free DMA descriptor for this DMA transfer. */
> +       spin_lock_irqsave(&mchan->chn_lock, irq_flags);
> +       if (!list_empty(&mchan->free)) {
> +               mdesc = list_first_entry(&mchan->free,
> +                                        struct sprd_dma_desc, node);
> +               list_del(&mdesc->node);
> +       }
> +       spin_unlock_irqrestore(&mchan->chn_lock, irq_flags);
> +
> +       if (!mdesc) {
> +               dev_err(sdev->dma_dev.dev, "get free descriptor failed\n");
> +               sprd_dma_process_completed(sdev);
> +               goto out;
> +       }
> +
> +       mdesc->dma_flags = flags;
> +
> +       /*
> +        * Set the DMA configuration into channel register of this DMA
> +        * descriptor. If we have multiple configuration, which means
> +        * need enable the link-list function, then we should set these
> +        * configuration into link-list address.
> +        */
> +       if (cfg_count == 1)
> +               ret = sprd_dma_config(chan, mdesc, &dma_cfg, NULL,
> +                                     SINGLE_CONFIG);
> +       else
> +               ret = sprd_dma_config_linklist(chan, mdesc, mchan->dma_cfg,
> +                                              cfg_count);
> +
> +       if (ret < 0) {
> +               spin_lock_irqsave(&mchan->chn_lock, irq_flags);
> +               list_add_tail(&mdesc->node, &mchan->free);
> +               spin_unlock_irqrestore(&mchan->chn_lock, irq_flags);
> +               dev_err(sdev->dma_dev.dev, "DMA configuration is failed\n");
> +               goto out;
> +       }
> +
> +       if (!(flags & DMA_HARDWARE_REQ))
> +               mchan->dev_id = DMA_SOFTWARE_UID;
> +
> +       /* add the free descriptor to the prepared list. */
> +       spin_lock_irqsave(&mchan->chn_lock, irq_flags);
> +       list_add_tail(&mdesc->node, &mchan->prepared);
> +       spin_unlock_irqrestore(&mchan->chn_lock, irq_flags);
> +
> +       mchan->cfg_count = 0;
> +       memset(mchan->dma_cfg, 0, sizeof(struct sprd_dma_cfg) *
> +              SPRD_DMA_CFG_COUNT);
> +       return &mdesc->desc;
> +
> +out:
> +       mchan->cfg_count = 0;
> +       memset(mchan->dma_cfg, 0, sizeof(struct sprd_dma_cfg) *
> +              SPRD_DMA_CFG_COUNT);
> +       return NULL;
> +}
> +
> +static int sprd_dma_pause(struct dma_chan *chan)
> +{
> +       struct sprd_dma_chn *mchan =
> +                       container_of(chan, struct sprd_dma_chn, chan);
> +       unsigned long flags;
> +
> +       spin_lock_irqsave(&mchan->chn_lock, flags);
> +       sprd_dma_stop(mchan);
> +       spin_unlock_irqrestore(&mchan->chn_lock, flags);
> +
> +       return 0;
> +}
> +
> +static int sprd_dma_resume(struct dma_chan *chan)
> +{
> +       struct sprd_dma_chn *mchan =
> +                       container_of(chan, struct sprd_dma_chn, chan);
> +       unsigned long flags;
> +       int ret;
> +
> +       spin_lock_irqsave(&mchan->chn_lock, flags);
> +       ret = sprd_dma_start(mchan);
> +       spin_unlock_irqrestore(&mchan->chn_lock, flags);
> +
> +       return ret;
> +}
> +
> +static int sprd_terminate_all(struct dma_chan *chan)
> +{
> +       struct sprd_dma_chn *mchan = to_sprd_dma_chan(chan);
> +       unsigned long flags;
> +
> +       spin_lock_irqsave(&mchan->chn_lock, flags);
> +       list_splice_tail_init(&mchan->prepared, &mchan->free);
> +       list_splice_tail_init(&mchan->queued, &mchan->free);
> +       list_splice_tail_init(&mchan->active, &mchan->free);
> +       list_splice_tail_init(&mchan->completed, &mchan->free);
> +
> +       sprd_dma_stop(mchan);
> +       spin_unlock_irqrestore(&mchan->chn_lock, flags);
> +
> +       return 0;
> +}
> +
> +static int sprd_dma_slave_config(struct dma_chan *chan,
> +                                struct dma_slave_config *config)
> +{
> +       struct sprd_dma_chn *mchan = to_sprd_dma_chan(chan);
> +       struct sprd_dma_cfg *sprd_cfg = container_of(config,
> +                                                    struct sprd_dma_cfg,
> +                                                    config);
> +       int i = 0;
> +
> +       do {
> +               memcpy(&mchan->dma_cfg[i], sprd_cfg, sizeof(*sprd_cfg));
> +               sprd_cfg++;
> +       } while (mchan->dma_cfg[i++].is_end == DMA_NOT_END
> +                && i < (SPRD_DMA_CFG_COUNT - 1));
> +
> +       mchan->cfg_count = i;
> +       return 0;
> +}
> +
> +static bool sprd_dma_filter_fn(struct dma_chan *chan, void *param)
> +{
> +       struct sprd_dma_chn *mchan = to_sprd_dma_chan(chan);
> +       struct of_phandle_args *dma_spec = (struct of_phandle_args *)param;
> +       unsigned int req = (unsigned int)dma_spec->args[0];
> +
> +       if (chan->device->dev->of_node == dma_spec->np)
> +               return req == (mchan->chn_num + 1);
> +       else
> +               return false;
> +}
> +
> +static struct dma_chan *sprd_dma_simple_xlate(struct of_phandle_args *dma_spec,
> +                                             struct of_dma *of_dma)
> +{
> +       struct of_dma_filter_info *info = of_dma->of_dma_data;
> +       int count = dma_spec->args_count;
> +
> +       if (!info || !info->filter_fn)
> +               return NULL;
> +
> +       if (count != 1)
> +               return NULL;
> +
> +       return dma_request_channel(info->dma_cap, info->filter_fn, dma_spec);
> +}
> +
> +static int sprd_dma_probe(struct platform_device *pdev)
> +{
> +       struct device_node *np = pdev->dev.of_node;
> +       struct sprd_dma_dev *sdev;
> +       struct sprd_dma_chn *dma_chn;
> +       struct resource *res;
> +       u32 chn_count;
> +       int ret, i;
> +
> +       if (of_property_read_u32(np, "#dma-channels", &chn_count)) {
> +               dev_err(&pdev->dev, "get dma channels count failed\n");
> +               return -ENODEV;
> +       }
> +
> +       sdev = devm_kzalloc(&pdev->dev, (sizeof(*sdev) +
> +                           (sizeof(struct sprd_dma_chn) * chn_count)),
> +                           GFP_KERNEL);
> +       if (!sdev)
> +               return -ENOMEM;
> +
> +       sdev->clk = devm_clk_get(&pdev->dev, "enable");
> +       if (IS_ERR(sdev->clk)) {
> +               dev_err(&pdev->dev, "get enable clock failed\n");
> +               return PTR_ERR(sdev->clk);
> +       }
> +
> +       /* ashb clock is optional for AGCP DMA */
> +       sdev->ashb_clk = devm_clk_get(&pdev->dev, "ashb_eb");
> +       if (IS_ERR(sdev->ashb_clk))
> +               dev_warn(&pdev->dev, "get ashb eb clock failed\n");
> +
> +       sdev->irq = platform_get_irq(pdev, 0);
> +       if (sdev->irq > 0) {
> +               ret = devm_request_irq(&pdev->dev, sdev->irq, dma_irq_handle,
> +                                      0, "sprd_dma", (void *)sdev);
> +               if (ret < 0) {
> +                       dev_err(&pdev->dev, "request dma irq failed\n");
> +                       return ret;
> +               }
> +
> +               tasklet_init(&sdev->tasklet, sprd_dma_tasklet,
> +                            (unsigned long)sdev);
> +       } else {
> +               dev_warn(&pdev->dev, "no interrupts for the DMA controller\n");
> +       }
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +       sdev->glb_base = devm_ioremap_nocache(&pdev->dev, res->start,
> +                                             resource_size(res));
> +       if (!sdev->glb_base)
> +               return -ENOMEM;
> +
> +       dma_cap_set(DMA_MEMCPY, sdev->dma_dev.cap_mask);
> +       sdev->total_chns = chn_count;
> +       sdev->dma_dev.chancnt = chn_count;
> +       INIT_LIST_HEAD(&sdev->dma_dev.channels);
> +       INIT_LIST_HEAD(&sdev->dma_dev.global_node);
> +       sdev->dma_dev.dev = &pdev->dev;
> +       sdev->dma_dev.device_alloc_chan_resources = sprd_dma_alloc_chan_resources;
> +       sdev->dma_dev.device_free_chan_resources = sprd_dma_free_chan_resources;
> +       sdev->dma_dev.device_tx_status = sprd_dma_tx_status;
> +       sdev->dma_dev.device_issue_pending = sprd_dma_issue_pending;
> +       sdev->dma_dev.device_prep_dma_memcpy = sprd_dma_prep_dma_memcpy;
> +       sdev->dma_dev.device_config = sprd_dma_slave_config;
> +       sdev->dma_dev.device_pause = sprd_dma_pause;
> +       sdev->dma_dev.device_resume = sprd_dma_resume;
> +       sdev->dma_dev.device_terminate_all = sprd_terminate_all;
> +
> +       for (i = 0; i < chn_count; i++) {
> +               dma_chn = &sdev->channels[i];
> +               dma_chn->chan.device = &sdev->dma_dev;
> +               dma_cookie_init(&dma_chn->chan);
> +               list_add_tail(&dma_chn->chan.device_node,
> +                             &sdev->dma_dev.channels);
> +
> +               dma_chn->chn_num = i;
> +               /* get each channel's registers base address. */
> +               dma_chn->chn_base = (void __iomem *)
> +                       ((unsigned long)sdev->glb_base +
> +                        SPRD_DMA_CHN_REG_OFFSET +
> +                        SPRD_DMA_CHN_REG_LENGTH * i);
> +
> +               spin_lock_init(&dma_chn->chn_lock);
> +               INIT_LIST_HEAD(&dma_chn->free);
> +               INIT_LIST_HEAD(&dma_chn->prepared);
> +               INIT_LIST_HEAD(&dma_chn->queued);
> +               INIT_LIST_HEAD(&dma_chn->active);
> +               INIT_LIST_HEAD(&dma_chn->completed);
> +       }
> +
> +       sdev->dma_desc_node_cachep = kmem_cache_create("dma_desc_node",
> +                                               sizeof(struct sprd_dma_desc), 0,
> +                                               SLAB_HWCACHE_ALIGN, NULL);
> +       if (!sdev->dma_desc_node_cachep) {
> +               dev_err(&pdev->dev, "allocate memory cache failed\n");
> +               return -ENOMEM;
> +       }
> +
> +       platform_set_drvdata(pdev, sdev);
> +       ret = sprd_dma_enable(sdev);
> +       if (ret)
> +               goto err_enable;
> +
> +       pm_runtime_set_active(&pdev->dev);
> +       pm_runtime_enable(&pdev->dev);
> +
> +       ret = pm_runtime_get_sync(&pdev->dev);
> +       if (ret < 0)
> +               goto err_rpm;
> +
> +       ret = dma_async_device_register(&sdev->dma_dev);
> +       if (ret < 0) {
> +               dev_err(&pdev->dev, "register dma device failed:%d\n", ret);
> +               goto err_register;
> +       }
> +
> +       sprd_dma_info.dma_cap = sdev->dma_dev.cap_mask;
> +       ret = of_dma_controller_register(np, sprd_dma_simple_xlate,
> +                                        &sprd_dma_info);
> +       if (ret) {
> +               dev_err(&pdev->dev, "failed to register of DMA controller\n");
> +               goto err_of_register;
> +       }
> +
> +       pm_runtime_put_sync(&pdev->dev);
> +       return 0;
> +
> +err_of_register:
> +       dma_async_device_unregister(&sdev->dma_dev);
> +err_register:
> +       pm_runtime_put_noidle(&pdev->dev);
> +       pm_runtime_disable(&pdev->dev);
> +err_rpm:
> +       sprd_dma_disable(sdev);
> +err_enable:
> +       kmem_cache_destroy(sdev->dma_desc_node_cachep);
> +       return ret;
> +}
> +
> +static int sprd_dma_remove(struct platform_device *pdev)
> +{
> +       struct sprd_dma_dev *sdev = platform_get_drvdata(pdev);
> +       int ret;
> +
> +       ret = pm_runtime_get_sync(&pdev->dev);
> +       if (ret < 0)
> +               return ret;
> +
> +       kmem_cache_destroy(sdev->dma_desc_node_cachep);
> +       dma_async_device_unregister(&sdev->dma_dev);
> +       sprd_dma_disable(sdev);
> +
> +       pm_runtime_put_noidle(&pdev->dev);
> +       pm_runtime_disable(&pdev->dev);
> +       return 0;
> +}
> +
> +static const struct of_device_id sprd_dma_match[] = {
> +       { .compatible = "sprd,sc9860-dma", },
> +       {},
> +};
> +
> +static int __maybe_unused sprd_dma_runtime_suspend(struct device *dev)
> +{
> +       struct sprd_dma_dev *sdev = dev_get_drvdata(dev);
> +
> +       sprd_dma_disable(sdev);
> +       return 0;
> +}
> +
> +static int __maybe_unused sprd_dma_runtime_resume(struct device *dev)
> +{
> +       struct sprd_dma_dev *sdev = dev_get_drvdata(dev);
> +
> +       return sprd_dma_enable(sdev);
> +}
> +
> +static const struct dev_pm_ops sprd_dma_pm_ops = {
> +       SET_RUNTIME_PM_OPS(sprd_dma_runtime_suspend,
> +                          sprd_dma_runtime_resume,
> +                          NULL)
> +};
> +
> +static struct platform_driver sprd_dma_driver = {
> +       .probe = sprd_dma_probe,
> +       .remove = sprd_dma_remove,
> +       .driver = {
> +               .name = "sprd-dma",
> +               .owner = THIS_MODULE,
> +               .of_match_table = sprd_dma_match,
> +               .pm = &sprd_dma_pm_ops,
> +       },
> +};
> +
> +static int __init sprd_dma_init(void)
> +{
> +       return platform_driver_register(&sprd_dma_driver);
> +}
> +arch_initcall_sync(sprd_dma_init);
> +
> +static void __exit sprd_dma_exit(void)
> +{
> +       platform_driver_unregister(&sprd_dma_driver);
> +}
> +module_exit(sprd_dma_exit);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("DMA driver for Spreadtrum");
> +MODULE_AUTHOR("Baolin Wang <baolin.wang@xxxxxxxxxxxxxx>");
> +MODULE_AUTHOR("Eric Long <eric.long@xxxxxxxxxxxxxx>");
> diff --git a/include/linux/dma/sprd-dma.h b/include/linux/dma/sprd-dma.h
> new file mode 100644
> index 0000000..40a8b1c
> --- /dev/null
> +++ b/include/linux/dma/sprd-dma.h
> @@ -0,0 +1,270 @@
> +/*
> + * Copyright (C) 2017 Spreadtrum Communications Inc.
> + *
> + * This software is licensed under the terms of the GNU General Public
> + * License version 2, as published by the Free Software Foundation, and
> + * may be copied, distributed, and modified under those terms.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#ifndef __SPRD_DMA_H
> +#define __SPRD_DMA_H
> +#include <linux/dmaengine.h>
> +
> +/* DMA request ID definition */
> +#define DMA_SOFTWARE_UID       0
> +#define DMA_SIM_RX             1
> +#define DMA_SIM_TX             2
> +#define DMA_IIS0_RX            3
> +#define DMA_IIS0_TX            4
> +#define DMA_IIS1_RX            5
> +#define DMA_IIS1_TX            6
> +#define DMA_IIS2_RX            7
> +#define DMA_IIS2_TX            8
> +#define DMA_IIS3_RX            9
> +#define DMA_IIS3_TX            10
> +#define DMA_SPI0_RX            11
> +#define DMA_SPI0_TX            12
> +#define DMA_SPI1_RX            13
> +#define DMA_SPI1_TX            14
> +#define DMA_SPI2_RX            15
> +#define DMA_SPI2_TX            16
> +#define DMA_UART0_RX           17
> +#define DMA_UART0_TX           18
> +#define DMA_UART1_RX           19
> +#define DMA_UART1_TX           20
> +#define DMA_UART2_RX           21
> +#define DMA_UART2_TX           22
> +#define DMA_UART3_RX           23
> +#define DMA_UART3_TX           24
> +#define DMA_UART4_RX           25
> +#define DMA_UART4_TX           26
> +#define DMA_DRM_CPT            27
> +#define DMA_DRM_RAW            28
> +#define DMA_VB_DA0             29
> +#define DMA_VB_DA1             30
> +#define DMA_VB_AD0             31
> +#define DMA_VB_AD1             32
> +#define DMA_VB_AD2             33
> +#define DMA_VB_AD3             34
> +#define DMA_GPS                        35
> +#define DMA_SDIO0_RD           36
> +#define DMA_SDIO0_WR           37
> +#define DMA_SDIO1_RD           38
> +#define DMA_SDIO1_WR           39
> +#define DMA_SDIO2_RD           40
> +#define DMA_SDIO2_WR           41
> +#define DMA_EMMC_RD            42
> +#define DMA_EMMC_WR            43
> +
> +/*
> + * enum dma_datawidth: define the DMA transfer data width
> + * @BYTE_WIDTH: 1 byte width
> + * @SHORT_WIDTH: 2 bytes width
> + * @WORD_WIDTH: 4 bytes width
> + * @DWORD_WIDTH: 8 bytes width
> + */
> +enum dma_datawidth {
> +       BYTE_WIDTH,
> +       SHORT_WIDTH,
> +       WORD_WIDTH,
> +       DWORD_WIDTH,
> +};
> +
> +/*
> + * enum dma_request_mode: define the DMA request mode
> + * @FRAG_REQ_MODE: fragment request mode
> + * @BLOCK_REQ_MODE: block request mode
> + * @TRANS_REQ_MODE: transaction request mode
> + * @LIST_REQ_MODE: link-list request mode
> + *
> + * We have 4 types request mode: fragment mode, block mode, transaction mode
> + * and linklist mode. One transaction can contain several blocks, one block can
> + * contain several fragments. Link-list mode means we can save several DMA
> + * configuration into one reserved memory, then DMA can fetch each DMA
> + * configuration automatically to start transfer.
> + */
> +enum dma_request_mode {
> +       FRAG_REQ_MODE,
> +       BLOCK_REQ_MODE,
> +       TRANS_REQ_MODE,
> +       LIST_REQ_MODE,
> +};
> +
> +/*
> + * enum dma_int_type: define the DMA interrupt type
> + * @NO_INT: do not need generate DMA interrupt.
> + * @FRAG_DONE: fragment done interrupt when one fragment request is done.
> + * @BLK_DONE: block done interrupt when one block request is done.
> + * @TRANS_DONE: tansaction done interrupt when one transaction request is done.
> + * @LIST_DONE: link-list done interrupt when one link-list request is done.
> + * @CONFIG_ERR: configure error interrupt when configuration is incorrect
> + * @BLOCK_FRAG_DONE: block and fragment interrupt when one fragment or block
> + * request is done.
> + * @TRANS_FRAG_DONE: transaction and fragment interrupt when one transaction
> + * request or fragment request is done.
> + * @TRANS_BLOCK_DONE: transaction and block interrupt when one transaction
> + * request or block request is done.
> + */
> +enum dma_int_type {
> +       NO_INT,
> +       FRAG_DONE,
> +       BLK_DONE,
> +       TRANS_DONE,
> +       LIST_DONE,
> +       CONFIG_ERR,
> +       BLOCK_FRAG_DONE,
> +       TRANS_FRAG_DONE,
> +       TRANS_BLOCK_DONE,
> +};
> +
> +/*
> + * enum dma_pri_level: define the DMA channel priority level
> + * @DMA_PRI_0: level 0
> + * @DMA_PRI_1: level 1
> + * @DMA_PRI_2: level 2
> + * @DMA_PRI_3: level 3
> + *
> + * When there are several DMA channels need to start, the DMA controller's
> + * arbitration will choose the high priority channel to start firstly.
> + */
> +enum dma_pri_level {
> +       DMA_PRI_0,
> +       DMA_PRI_1,
> +       DMA_PRI_2,
> +       DMA_PRI_3,
> +};
> +
> +/*
> + * enum dma_switch_mode: define the DMA transfer format
> + * @DATA_ABCD: ABCD to ABCD
> + * @DATA_DCBA: ABCD to DCBA
> + * @DATA_BADC: ABCD to BADC
> + * @DATA_CDAB: ABCD to CDAB
> + */
> +enum dma_switch_mode {
> +       DATA_ABCD,
> +       DATA_DCBA,
> +       DATA_BADC,
> +       DATA_CDAB,
> +};
> +
> +/*
> + * enum dma_end_type: define the DMA configuration end type
> + * @DMA_NOT_END: DMA configuration is not end
> + * @DMA_END: DMA configuration is end but not one link-list cycle configuration
> + * @DMA_LINK: DMA configuration is end but it is one link-list cycle
> + * configuration
> + *
> + * Since DMA contrller can support link-list transfer mode, that means user can
> + * supply several DMA configuration and each configuration can be pointed by
> + * previous link pointer register, then DMA controller will start to transfer
> + * for each DMA configuration automatically. DMA_END and DMA_LINK flag can
> + * indicate these several configuration is end, but DMA_LINK can also indicate
> + * these listed configuration is one cycle. For example if we have 4 group DMA
> + * configuration and we set DMA_LINK, which means it will start to transfer from
> + * cfg0--->cfg1--->cfg2--->cfg3, then back to cfg0 as one cycle.
> + */
> +enum dma_end_type {
> +       DMA_NOT_END,
> +       DMA_END,
> +       DMA_LINK,
> +};
> +
> +/*
> + * enum dma_flags: define the DMA flags
> + * @DMA_HARDWARE_REQ: hardware request channel to start transfer by hardware id.
> + * @DMA_SOFTWARE_REQ: software request channel to start transfer.
> + * @DMA_GROUP1_SRC: indicate this is source channel of group 1 which can be
> + * start another channel.
> + * @DMA_GROUP1_DST: indicate this is destination channel of group 1 which will
> + * be started by source channel.
> + * @DMA_GROUP2_SRC: indicate this is source channel of group 2 which can be
> + * start another channel.
> + * @DMA_GROUP2_DST: indicate this is destination channel of group 2 which will
> + * be started by source channel.
> + * @DMA_MUTL_FRAG_DONE: when fragment is done of source channel which will
> + * start another destination channel.
> + * @DMA_MUTL_BLK_DONE: when block is done of source channel which will start
> + * another destination channel.
> + * @DMA_MUTL_TRANS_DONE: when transaction is done of source channel which will
> + * start another destination channel.
> + * @DMA_MUTL_LIST_DONE: when link-list is done of source channel which will
> + * start another destination channel.
> + *
> + * Since DMA controller can support 2 stage transfer which means when one
> + * channel transfer is done, then it can start another channel's transfer
> + * automatically by interrupt type.
> + */
> +enum dma_flags {
> +       DMA_HARDWARE_REQ = BIT(0),
> +       DMA_SOFTWARE_REQ = BIT(1),
> +       DMA_GROUP1_SRC = BIT(2),
> +       DMA_GROUP1_DST = BIT(3),
> +       DMA_GROUP2_SRC = BIT(4),
> +       DMA_GROUP2_DST = BIT(5),
> +       DMA_MUTL_FRAG_DONE = BIT(6),
> +       DMA_MUTL_BLK_DONE = BIT(7),
> +       DMA_MUTL_TRANS_DONE = BIT(8),
> +       DMA_MUTL_LIST_DONE = BIT(9),
> +};
> +
> +/*
> + * struct sprd_dma_cfg: DMA configuration for users
> + * @config: salve config structure
> + * @chn_pri: the channel priority
> + * @datawidth: the data width
> + * @req_mode: the request mode
> + * @irq_mode: the interrupt mode
> + * @swt_mode: the switch mode
> + * @link_cfg_v: point to the virtual memory address to save link-list DMA
> + * configuration
> + * @link_cfg_p: point to the physical memory address to save link-list DMA
> + * configuration
> + * @src_addr: the source address
> + * @des_addr: the destination address
> + * @fragmens_len: one fragment request length
> + * @block_len; one block request length
> + * @transcation_len: one transaction request length
> + * @src_step: source side transfer step
> + * @des_step: destination side transfer step
> + * @src_frag_step: source fragment transfer step
> + * @dst_frag_step: destination fragment transfer step
> + * @src_blk_step: source block transfer step
> + * @dst_blk_step: destination block transfer step
> + * @wrap_ptr: wrap jump pointer address
> + * @wrap_to: wrap jump to address
> + * @dev_id: hardware device id to start DMA transfer
> + * @is_end: DMA configuration end type
> + */
> +struct sprd_dma_cfg {
> +       struct dma_slave_config config;
> +       enum dma_pri_level chn_pri;
> +       enum dma_datawidth datawidth;
> +       enum dma_request_mode req_mode;
> +       enum dma_int_type irq_mode;
> +       enum dma_switch_mode swt_mode;
> +       unsigned long link_cfg_v;
> +       unsigned long link_cfg_p;
> +       unsigned long src_addr;
> +       unsigned long des_addr;
> +       u32 fragmens_len;
> +       u32 block_len;
> +       u32 transcation_len;
> +       u32 src_step;
> +       u32 des_step;
> +       u32 src_frag_step;
> +       u32 dst_frag_step;
> +       u32 src_blk_step;
> +       u32 dst_blk_step;
> +       u32 wrap_ptr;
> +       u32 wrap_to;
> +       u32 dev_id;
> +       enum dma_end_type is_end;
> +};
> +
> +#endif
> --
> 1.7.9.5
>
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux