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author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-10-25 16:43:18 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-10-25 16:43:18 +0300 |
commit | a41efc2a0f68cea26665ab9e6d991c9bf33b3f59 (patch) | |
tree | 4fb79cbd5ada8f501ba49234f0c84964de943112 /include/linux/dma/sprd-dma.h | |
parent | 36168d7123311d52e085c116f6c66e16f0b84615 (diff) | |
parent | 71f021cf6de822ac49a790509683fbb4a06ce4bf (diff) | |
download | linux-a41efc2a0f68cea26665ab9e6d991c9bf33b3f59.tar.xz |
Merge tag 'dmaengine-4.20-rc1' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine updates from Vinod Koul:
- Support for ColdFire mcf5441x edma controller
- Support for link list mode in sprd dma
- More users of managed dmaenginem_async_device_register API
- Cyclic mode support in owl dma driver
- DT updates for renesas drivers, dma-jz4780 updates and support for
JZ4770, JZ4740 and JZ4725B controllers
- Removal of deprecated dma_slave_config direction in dmaengine
drivers, few more users will be removed in next cycle and eventually
removed.
- Minor updates to idma64, ioat, pxa, ppc drivers
* tag 'dmaengine-4.20-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (66 commits)
dmaengine: ppc4xx: fix off-by-one build failure
dmaengine: owl: Fix warnings generated during build
dmaengine: fsl-edma: remove dma_slave_config direction usage
dmaengine: rcar-dmac: set scatter/gather max segment size
dmaengine: mmp_tdma: remove dma_slave_config direction usage
dmaengine: ep93xx_dma: remove dma_slave_config direction usage
dmaengine: k3dma: remove dma_slave_config direction usage
dmaengine: k3dma: dont use direction for memcpy
dmaengine: imx-dma: remove dma_slave_config direction usage
dmaengine: idma: remove dma_slave_config direction usage
dmaengine: hsu: remove dma_slave_config direction usage
dmaengine: dw: remove dma_slave_config direction usage
dmaengine: jz4740: remove dma_slave_config direction usage
dmaengine: coh901318: remove dma_slave_config direction usage
dmaengine: bcm2835: remove dma_slave_config direction usage
dmaengine: at_hdmac: remove dma_slave_config direction usage
dmaengine: owl: Add Slave and Cyclic mode support for Actions Semi Owl S900 SoC
dmaengine: ioat: fix prototype of ioat_enumerate_channels
dmaengine: stm32-dma: check whether length is aligned on FIFO threshold
dt-bindings: dmaengine: usb-dmac: Add binding for r8a7744
...
Diffstat (limited to 'include/linux/dma/sprd-dma.h')
-rw-r--r-- | include/linux/dma/sprd-dma.h | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/include/linux/dma/sprd-dma.h b/include/linux/dma/sprd-dma.h index b0115e340fbc..b42b80e52cc2 100644 --- a/include/linux/dma/sprd-dma.h +++ b/include/linux/dma/sprd-dma.h @@ -58,4 +58,73 @@ enum sprd_dma_int_type { 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 + * + * 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; +}; + #endif |