linux-stable/include/linux/dma/sprd-dma.h
Eric Long a7e335deed dmaengine: sprd: Add wrap address support for link-list mode
The Spreadtrum Audio compress offload mode will use 2-stage DMA transfer
to save power. That means we can request 2 dma channels, one for source
channel, and another one for destination channel. Once the source channel's
transaction is done, it will trigger the destination channel's transaction
automatically by hardware signal.

In this case, the source channel will transfer data from IRAM buffer to
the DSP fifo to decoding/encoding, once IRAM buffer is empty by transferring
done, the destination channel will start to transfer data from DDR buffer
to IRAM buffer. Since the destination channel will use link-list mode to
fill the IRAM data, and IRAM buffer is allocated by 32K, and DDR buffer
is larger to 2M, that means we need lots of link-list nodes to do a cyclic
transfer, instead wasting lots of link-list memory, we can use wrap address
support to reduce link-list node number, which means when the transfer
address reaches the wrap address, the transfer address will jump to the
wrap_to address specified by wrap_to register, and only 2 link-list nodes
can do a cyclic transfer to transfer data from DDR to IRAM.

Thus this patch adds wrap address to support this case.

[Baolin Wang changes the commit message]
Signed-off-by: Eric Long <eric.long@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Link: https://lore.kernel.org/r/85a5484bc1f3dd53ce6f92700ad8b35f30a0b096.1571812029.git.baolin.wang@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-11-14 16:03:35 +05:30

190 lines
8.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _SPRD_DMA_H_
#define _SPRD_DMA_H_
#define SPRD_DMA_REQ_SHIFT 8
#define SPRD_DMA_TRG_MODE_SHIFT 16
#define SPRD_DMA_CHN_MODE_SHIFT 24
#define SPRD_DMA_FLAGS(chn_mode, trg_mode, req_mode, int_type) \
((chn_mode) << SPRD_DMA_CHN_MODE_SHIFT | \
(trg_mode) << SPRD_DMA_TRG_MODE_SHIFT | \
(req_mode) << SPRD_DMA_REQ_SHIFT | (int_type))
/*
* The Spreadtrum DMA controller supports channel 2-stage tansfer, that means
* we can request 2 dma channels, one for source channel, and another one for
* destination channel. Each channel is independent, and has its own
* configurations. Once the source channel's transaction is done, it will
* trigger the destination channel's transaction automatically by hardware
* signal.
*
* To support 2-stage tansfer, we must configure the channel mode and trigger
* mode as below definition.
*/
/*
* enum sprd_dma_chn_mode: define the DMA channel mode for 2-stage transfer
* @SPRD_DMA_CHN_MODE_NONE: No channel mode setting which means channel doesn't
* support the 2-stage transfer.
* @SPRD_DMA_SRC_CHN0: Channel used as source channel 0.
* @SPRD_DMA_SRC_CHN1: Channel used as source channel 1.
* @SPRD_DMA_DST_CHN0: Channel used as destination channel 0.
* @SPRD_DMA_DST_CHN1: Channel used as destination channel 1.
*
* Now the DMA controller can supports 2 groups 2-stage transfer.
*/
enum sprd_dma_chn_mode {
SPRD_DMA_CHN_MODE_NONE,
SPRD_DMA_SRC_CHN0,
SPRD_DMA_SRC_CHN1,
SPRD_DMA_DST_CHN0,
SPRD_DMA_DST_CHN1,
};
/*
* enum sprd_dma_trg_mode: define the DMA channel trigger mode for 2-stage
* transfer
* @SPRD_DMA_NO_TRG: No trigger setting.
* @SPRD_DMA_FRAG_DONE_TRG: Trigger the transaction of destination channel
* automatically once the source channel's fragment request is done.
* @SPRD_DMA_BLOCK_DONE_TRG: Trigger the transaction of destination channel
* automatically once the source channel's block request is done.
* @SPRD_DMA_TRANS_DONE_TRG: Trigger the transaction of destination channel
* automatically once the source channel's transfer request is done.
* @SPRD_DMA_LIST_DONE_TRG: Trigger the transaction of destination channel
* automatically once the source channel's link-list request is done.
*/
enum sprd_dma_trg_mode {
SPRD_DMA_NO_TRG,
SPRD_DMA_FRAG_DONE_TRG,
SPRD_DMA_BLOCK_DONE_TRG,
SPRD_DMA_TRANS_DONE_TRG,
SPRD_DMA_LIST_DONE_TRG,
};
/*
* enum sprd_dma_req_mode: define the DMA request mode
* @SPRD_DMA_FRAG_REQ: fragment request mode
* @SPRD_DMA_BLK_REQ: block request mode
* @SPRD_DMA_TRANS_REQ: transaction request mode
* @SPRD_DMA_LIST_REQ: 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 sprd_dma_req_mode {
SPRD_DMA_FRAG_REQ,
SPRD_DMA_BLK_REQ,
SPRD_DMA_TRANS_REQ,
SPRD_DMA_LIST_REQ,
};
/*
* enum sprd_dma_int_type: define the DMA interrupt type
* @SPRD_DMA_NO_INT: do not need generate DMA interrupts.
* @SPRD_DMA_FRAG_INT: fragment done interrupt when one fragment request
* is done.
* @SPRD_DMA_BLK_INT: block done interrupt when one block request is done.
* @SPRD_DMA_BLK_FRAG_INT: block and fragment interrupt when one fragment
* or one block request is done.
* @SPRD_DMA_TRANS_INT: tansaction done interrupt when one transaction
* request is done.
* @SPRD_DMA_TRANS_FRAG_INT: transaction and fragment interrupt when one
* transaction request or fragment request is done.
* @SPRD_DMA_TRANS_BLK_INT: transaction and block interrupt when one
* transaction request or block request is done.
* @SPRD_DMA_LIST_INT: link-list done interrupt when one link-list request
* is done.
* @SPRD_DMA_CFGERR_INT: configure error interrupt when configuration is
* incorrect.
*/
enum sprd_dma_int_type {
SPRD_DMA_NO_INT,
SPRD_DMA_FRAG_INT,
SPRD_DMA_BLK_INT,
SPRD_DMA_BLK_FRAG_INT,
SPRD_DMA_TRANS_INT,
SPRD_DMA_TRANS_FRAG_INT,
SPRD_DMA_TRANS_BLK_INT,
SPRD_DMA_LIST_INT,
SPRD_DMA_CFGERR_INT,
};
/*
* struct sprd_dma_linklist - DMA link-list address structure
* @virt_addr: link-list virtual address to configure link-list node
* @phy_addr: link-list physical address to link DMA transfer
* @wrap_addr: the wrap address for link-list mode, which means once the
* transfer address reaches the wrap address, the next transfer address
* will jump to the address specified by wrap_to register.
*
* The Spreadtrum DMA controller supports the link-list mode, that means slaves
* can supply several groups configurations (each configuration represents one
* DMA transfer) saved in memory, and DMA controller will link these groups
* configurations by writing the physical address of each configuration into the
* link-list register.
*
* Just as shown below, the link-list pointer register will be pointed to the
* physical address of 'configuration 1', and the 'configuration 1' link-list
* pointer will be pointed to 'configuration 2', and so on.
* Once trigger the DMA transfer, the DMA controller will load 'configuration
* 1' to its registers automatically, after 'configuration 1' transaction is
* done, DMA controller will load 'configuration 2' automatically, until all
* DMA transactions are done.
*
* Note: The last link-list pointer should point to the physical address
* of 'configuration 1', which can avoid DMA controller loads incorrect
* configuration when the last configuration transaction is done.
*
* DMA controller linklist memory
* ====================== -----------------------
*| | | configuration 1 |<---
*| DMA controller | ------->| | |
*| | | | | |
*| | | | | |
*| | | | | |
*| linklist pointer reg |---- ----| linklist pointer | |
* ====================== | ----------------------- |
* | |
* | ----------------------- |
* | | configuration 2 | |
* --->| | |
* | | |
* | | |
* | | |
* ----| linklist pointer | |
* | ----------------------- |
* | |
* | ----------------------- |
* | | configuration 3 | |
* --->| | |
* | | |
* | . | |
* . |
* . |
* . |
* | . |
* | ----------------------- |
* | | configuration n | |
* --->| | |
* | | |
* | | |
* | | |
* | linklist pointer |----
* -----------------------
*
* To support the link-list mode, DMA slaves should allocate one segment memory
* from always-on IRAM or dma coherent memory to store these groups of DMA
* configuration, and pass the virtual and physical address to DMA controller.
*/
struct sprd_dma_linklist {
unsigned long virt_addr;
phys_addr_t phy_addr;
phys_addr_t wrap_addr;
};
#endif