linux-sg2042/drivers/dma/dw-edma/Kconfig

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dmaengine: Add Synopsys eDMA IP core driver Add Synopsys PCIe Endpoint eDMA IP core driver to kernel. This IP is generally distributed with Synopsys PCIe Endpoint IP (depends of the use and licensing agreement). This core driver, initializes and configures the eDMA IP using vma-helpers functions and dma-engine subsystem. This driver can be compile as built-in or external module in kernel. To enable this driver just select DW_EDMA option in kernel configuration, however it requires and selects automatically DMA_ENGINE and DMA_VIRTUAL_CHANNELS option too. In order to transfer data from point A to B as fast as possible this IP requires a dedicated memory space containing linked list of elements. All elements of this linked list are continuous and each one describes a data transfer (source and destination addresses, length and a control variable). For the sake of simplicity, lets assume a memory space for channel write 0 which allows about 42 elements. +---------+ | Desc #0 |-+ +---------+ | V +----------+ | Chunk #0 |-+ | CB = 1 | | +----------+ +-----+ +-----------+ +-----+ +----------+ +->| Burst #0 |->| ... |->| Burst #41 |->| llp | | +----------+ +-----+ +-----------+ +-----+ V +----------+ | Chunk #1 |-+ | CB = 0 | | +-----------+ +-----+ +-----------+ +-----+ +----------+ +->| Burst #42 |->| ... |->| Burst #83 |->| llp | | +-----------+ +-----+ +-----------+ +-----+ V +----------+ | Chunk #2 |-+ | CB = 1 | | +-----------+ +-----+ +------------+ +-----+ +----------+ +->| Burst #84 |->| ... |->| Burst #125 |->| llp | | +-----------+ +-----+ +------------+ +-----+ V +----------+ | Chunk #3 |-+ | CB = 0 | | +------------+ +-----+ +------------+ +-----+ +----------+ +->| Burst #126 |->| ... |->| Burst #129 |->| llp | +------------+ +-----+ +------------+ +-----+ Legend: - Linked list, also know as Chunk - Linked list element*, also know as Burst *CB*, also know as Change Bit, it's a control bit (and typically is toggled) that allows to easily identify and differentiate between the current linked list and the previous or the next one. - LLP, is a special element that indicates the end of the linked list element stream also informs that the next CB should be toggle On every last Burst of the Chunk (Burst #41, Burst #83, Burst #125 or even Burst #129) is set some flags on their control variable (RIE and LIE bits) that will trigger the send of "done" interruption. On the interruptions callback, is decided whether to recycle the linked list memory space by writing a new set of Bursts elements (if still exists Chunks to transfer) or is considered completed (if there is no Chunks available to transfer). On scatter-gather transfer mode, the client will submit a scatter-gather list of n (on this case 130) elements, that will be divide in multiple Chunks, each Chunk will have (on this case 42) a limited number of Bursts and after transferring all Bursts, an interrupt will be triggered, which will allow to recycle the all linked list dedicated memory again with the new information relative to the next Chunk and respective Burst associated and repeat the whole cycle again. On cyclic transfer mode, the client will submit a buffer pointer, length of it and number of repetitions, in this case each burst will correspond directly to each repetition. Each Burst can describes a data transfer from point A(source) to point B(destination) with a length that can be from 1 byte up to 4 GB. Since dedicated the memory space where the linked list will reside is limited, the whole n burst elements will be organized in several Chunks, that will be used later to recycle the dedicated memory space to initiate a new sequence of data transfers. The whole transfer is considered has completed when it was transferred all bursts. Currently this IP has a set well-known register map, which includes support for legacy and unroll modes. Legacy mode is version of this register map that has multiplexer register that allows to switch registers between all write and read channels and the unroll modes repeats all write and read channels registers with an offset between them. This register map is called v0. The IP team is creating a new register map more suitable to the latest PCIe features, that very likely will change the map register, which this version will be called v1. As soon as this new version is released by the IP team the support for this version in be included on this driver. According to the logic, patches 1, 2 and 3 should be squashed into 1 unique patch, but for the sake of simplicity of review, it was divided in this 3 patches files. Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> Cc: Vinod Koul <vkoul@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Joao Pinto <jpinto@synopsys.com> Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-06-04 21:29:22 +08:00
# SPDX-License-Identifier: GPL-2.0
config DW_EDMA
tristate "Synopsys DesignWare eDMA controller driver"
depends on PCI && PCI_MSI
dmaengine: Add Synopsys eDMA IP core driver Add Synopsys PCIe Endpoint eDMA IP core driver to kernel. This IP is generally distributed with Synopsys PCIe Endpoint IP (depends of the use and licensing agreement). This core driver, initializes and configures the eDMA IP using vma-helpers functions and dma-engine subsystem. This driver can be compile as built-in or external module in kernel. To enable this driver just select DW_EDMA option in kernel configuration, however it requires and selects automatically DMA_ENGINE and DMA_VIRTUAL_CHANNELS option too. In order to transfer data from point A to B as fast as possible this IP requires a dedicated memory space containing linked list of elements. All elements of this linked list are continuous and each one describes a data transfer (source and destination addresses, length and a control variable). For the sake of simplicity, lets assume a memory space for channel write 0 which allows about 42 elements. +---------+ | Desc #0 |-+ +---------+ | V +----------+ | Chunk #0 |-+ | CB = 1 | | +----------+ +-----+ +-----------+ +-----+ +----------+ +->| Burst #0 |->| ... |->| Burst #41 |->| llp | | +----------+ +-----+ +-----------+ +-----+ V +----------+ | Chunk #1 |-+ | CB = 0 | | +-----------+ +-----+ +-----------+ +-----+ +----------+ +->| Burst #42 |->| ... |->| Burst #83 |->| llp | | +-----------+ +-----+ +-----------+ +-----+ V +----------+ | Chunk #2 |-+ | CB = 1 | | +-----------+ +-----+ +------------+ +-----+ +----------+ +->| Burst #84 |->| ... |->| Burst #125 |->| llp | | +-----------+ +-----+ +------------+ +-----+ V +----------+ | Chunk #3 |-+ | CB = 0 | | +------------+ +-----+ +------------+ +-----+ +----------+ +->| Burst #126 |->| ... |->| Burst #129 |->| llp | +------------+ +-----+ +------------+ +-----+ Legend: - Linked list, also know as Chunk - Linked list element*, also know as Burst *CB*, also know as Change Bit, it's a control bit (and typically is toggled) that allows to easily identify and differentiate between the current linked list and the previous or the next one. - LLP, is a special element that indicates the end of the linked list element stream also informs that the next CB should be toggle On every last Burst of the Chunk (Burst #41, Burst #83, Burst #125 or even Burst #129) is set some flags on their control variable (RIE and LIE bits) that will trigger the send of "done" interruption. On the interruptions callback, is decided whether to recycle the linked list memory space by writing a new set of Bursts elements (if still exists Chunks to transfer) or is considered completed (if there is no Chunks available to transfer). On scatter-gather transfer mode, the client will submit a scatter-gather list of n (on this case 130) elements, that will be divide in multiple Chunks, each Chunk will have (on this case 42) a limited number of Bursts and after transferring all Bursts, an interrupt will be triggered, which will allow to recycle the all linked list dedicated memory again with the new information relative to the next Chunk and respective Burst associated and repeat the whole cycle again. On cyclic transfer mode, the client will submit a buffer pointer, length of it and number of repetitions, in this case each burst will correspond directly to each repetition. Each Burst can describes a data transfer from point A(source) to point B(destination) with a length that can be from 1 byte up to 4 GB. Since dedicated the memory space where the linked list will reside is limited, the whole n burst elements will be organized in several Chunks, that will be used later to recycle the dedicated memory space to initiate a new sequence of data transfers. The whole transfer is considered has completed when it was transferred all bursts. Currently this IP has a set well-known register map, which includes support for legacy and unroll modes. Legacy mode is version of this register map that has multiplexer register that allows to switch registers between all write and read channels and the unroll modes repeats all write and read channels registers with an offset between them. This register map is called v0. The IP team is creating a new register map more suitable to the latest PCIe features, that very likely will change the map register, which this version will be called v1. As soon as this new version is released by the IP team the support for this version in be included on this driver. According to the logic, patches 1, 2 and 3 should be squashed into 1 unique patch, but for the sake of simplicity of review, it was divided in this 3 patches files. Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> Cc: Vinod Koul <vkoul@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Joao Pinto <jpinto@synopsys.com> Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-06-04 21:29:22 +08:00
select DMA_ENGINE
select DMA_VIRTUAL_CHANNELS
help
Support the Synopsys DesignWare eDMA controller, normally
implemented on endpoints SoCs.
dmaengine: Add Synopsys eDMA IP PCIe glue-logic Synopsys eDMA IP is normally distributed along with Synopsys PCIe EndPoint IP (depends of the use and licensing agreement). This IP requires some basic configurations, such as: - eDMA registers BAR - eDMA registers offset - eDMA registers size - eDMA linked list memory BAR - eDMA linked list memory offset - eDMA linked list memory size - eDMA data memory BAR - eDMA data memory offset - eDMA data memory size - eDMA version - eDMA mode - IRQs available for eDMA As a working example, PCIe glue-logic will attach to a Synopsys PCIe EndPoint IP prototype kit (Vendor ID = 0x16c3, Device ID = 0xedda), which has built-in an eDMA IP with this default configuration: - eDMA registers BAR = 0 - eDMA registers offset = 0x00001000 (4 Kbytes) - eDMA registers size = 0x00002000 (8 Kbytes) - eDMA linked list memory BAR = 2 - eDMA linked list memory offset = 0x00000000 (0 Kbytes) - eDMA linked list memory size = 0x00800000 (8 Mbytes) - eDMA data memory BAR = 2 - eDMA data memory offset = 0x00800000 (8 Mbytes) - eDMA data memory size = 0x03800000 (56 Mbytes) - eDMA version = 0 - eDMA mode = EDMA_MODE_UNROLL - IRQs = 1 This driver can be compile as built-in or external module in kernel. To enable this driver just select DW_EDMA_PCIE option in kernel configuration, however it requires and selects automatically DW_EDMA option too. Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> Cc: Vinod Koul <vkoul@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Joao Pinto <jpinto@synopsys.com> Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-06-04 21:29:26 +08:00
config DW_EDMA_PCIE
tristate "Synopsys DesignWare eDMA PCIe driver"
depends on PCI && PCI_MSI
select DW_EDMA
help
Provides a glue-logic between the Synopsys DesignWare
eDMA controller and an endpoint PCIe device. This also serves
as a reference design to whom desires to use this IP.