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
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/* SPDX-License-Identifier: GPL-2.0 */
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/*
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* Copyright (c) 2018-2019 Synopsys, Inc. and/or its affiliates.
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* Synopsys DesignWare eDMA core driver
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*
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* Author: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
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*/
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#ifndef _DW_EDMA_H
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#define _DW_EDMA_H
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#include <linux/device.h>
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#include <linux/dmaengine.h>
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2022-05-24 23:21:53 +08:00
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#define EDMA_MAX_WR_CH 8
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#define EDMA_MAX_RD_CH 8
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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
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struct dw_edma;
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2022-05-24 23:21:53 +08:00
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struct dw_edma_region {
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phys_addr_t paddr;
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void __iomem *vaddr;
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size_t sz;
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};
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struct dw_edma_core_ops {
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int (*irq_vector)(struct device *dev, unsigned int nr);
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};
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enum dw_edma_map_format {
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EDMA_MF_EDMA_LEGACY = 0x0,
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EDMA_MF_EDMA_UNROLL = 0x1,
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EDMA_MF_HDMA_COMPAT = 0x5
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};
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2022-05-24 23:21:58 +08:00
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/**
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* enum dw_edma_chip_flags - Flags specific to an eDMA chip
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* @DW_EDMA_CHIP_LOCAL: eDMA is used locally by an endpoint
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*/
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enum dw_edma_chip_flags {
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DW_EDMA_CHIP_LOCAL = BIT(0),
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};
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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
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/**
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* struct dw_edma_chip - representation of DesignWare eDMA controller hardware
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* @dev: struct device of the eDMA controller
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* @id: instance ID
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2022-05-24 23:21:53 +08:00
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* @nr_irqs: total number of DMA IRQs
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* @ops DMA channel to IRQ number mapping
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2022-05-24 23:21:58 +08:00
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* @flags dw_edma_chip_flags
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2022-05-24 23:21:54 +08:00
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* @reg_base DMA register base address
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2022-05-24 23:21:55 +08:00
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* @ll_wr_cnt DMA write link list count
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* @ll_rd_cnt DMA read link list count
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2022-05-24 23:21:53 +08:00
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* @rg_region DMA register region
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* @ll_region_wr DMA descriptor link list memory for write channel
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* @ll_region_rd DMA descriptor link list memory for read channel
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* @dt_region_wr DMA data memory for write channel
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* @dt_region_rd DMA data memory for read channel
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* @mf DMA register map format
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* @dw: struct dw_edma that is filled by dw_edma_probe()
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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
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*/
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struct dw_edma_chip {
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struct device *dev;
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int id;
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2022-05-24 23:21:53 +08:00
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int nr_irqs;
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const struct dw_edma_core_ops *ops;
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2022-05-24 23:21:58 +08:00
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u32 flags;
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2022-05-24 23:21:53 +08:00
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2022-05-24 23:21:54 +08:00
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void __iomem *reg_base;
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2022-05-24 23:21:53 +08:00
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2022-05-24 23:21:55 +08:00
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u16 ll_wr_cnt;
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u16 ll_rd_cnt;
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2022-05-24 23:21:53 +08:00
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/* link list address */
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struct dw_edma_region ll_region_wr[EDMA_MAX_WR_CH];
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struct dw_edma_region ll_region_rd[EDMA_MAX_RD_CH];
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/* data region */
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struct dw_edma_region dt_region_wr[EDMA_MAX_WR_CH];
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struct dw_edma_region dt_region_rd[EDMA_MAX_RD_CH];
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enum dw_edma_map_format mf;
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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
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struct dw_edma *dw;
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};
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/* Export to the platform drivers */
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#if IS_ENABLED(CONFIG_DW_EDMA)
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int dw_edma_probe(struct dw_edma_chip *chip);
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int dw_edma_remove(struct dw_edma_chip *chip);
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#else
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static inline int dw_edma_probe(struct dw_edma_chip *chip)
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{
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return -ENODEV;
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}
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static inline int dw_edma_remove(struct dw_edma_chip *chip)
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{
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return 0;
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}
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#endif /* CONFIG_DW_EDMA */
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#endif /* _DW_EDMA_H */
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