diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/dma/atmel-dma.txt | 2 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/powerpc/fsl/dma.txt | 138 | ||||
| -rw-r--r-- | Documentation/dmatest.txt | 72 |
3 files changed, 143 insertions, 69 deletions
diff --git a/Documentation/devicetree/bindings/dma/atmel-dma.txt b/Documentation/devicetree/bindings/dma/atmel-dma.txt index e1f343c7a34b..f69bcf5a6343 100644 --- a/Documentation/devicetree/bindings/dma/atmel-dma.txt +++ b/Documentation/devicetree/bindings/dma/atmel-dma.txt @@ -28,7 +28,7 @@ The three cells in order are: dependent: - bit 7-0: peripheral identifier for the hardware handshaking interface. The identifier can be different for tx and rx. - - bit 11-8: FIFO configuration. 0 for half FIFO, 1 for ALAP, 1 for ASAP. + - bit 11-8: FIFO configuration. 0 for half FIFO, 1 for ALAP, 2 for ASAP. Example: diff --git a/Documentation/devicetree/bindings/powerpc/fsl/dma.txt b/Documentation/devicetree/bindings/powerpc/fsl/dma.txt index 2a4b4bce6110..7fc1b010fa75 100644 --- a/Documentation/devicetree/bindings/powerpc/fsl/dma.txt +++ b/Documentation/devicetree/bindings/powerpc/fsl/dma.txt @@ -1,33 +1,30 @@ -* Freescale 83xx DMA Controller +* Freescale DMA Controllers -Freescale PowerPC 83xx have on chip general purpose DMA controllers. +** Freescale Elo DMA Controller + This is a little-endian 4-channel DMA controller, used in Freescale mpc83xx + series chips such as mpc8315, mpc8349, mpc8379 etc. Required properties: -- compatible : compatible list, contains 2 entries, first is - "fsl,CHIP-dma", where CHIP is the processor - (mpc8349, mpc8360, etc.) and the second is - "fsl,elo-dma" -- reg : <registers mapping for DMA general status reg> -- ranges : Should be defined as specified in 1) to describe the - DMA controller channels. +- compatible : must include "fsl,elo-dma" +- reg : DMA General Status Register, i.e. DGSR which contains + status for all the 4 DMA channels +- ranges : describes the mapping between the address space of the + DMA channels and the address space of the DMA controller - cell-index : controller index. 0 for controller @ 0x8100 -- interrupts : <interrupt mapping for DMA IRQ> +- interrupts : interrupt specifier for DMA IRQ - interrupt-parent : optional, if needed for interrupt mapping - - DMA channel nodes: - - compatible : compatible list, contains 2 entries, first is - "fsl,CHIP-dma-channel", where CHIP is the processor - (mpc8349, mpc8350, etc.) and the second is - "fsl,elo-dma-channel". However, see note below. - - reg : <registers mapping for channel> - - cell-index : dma channel index starts at 0. + - compatible : must include "fsl,elo-dma-channel" + However, see note below. + - reg : DMA channel specific registers + - cell-index : DMA channel index starts at 0. Optional properties: - - interrupts : <interrupt mapping for DMA channel IRQ> - (on 83xx this is expected to be identical to - the interrupts property of the parent node) + - interrupts : interrupt specifier for DMA channel IRQ + (on 83xx this is expected to be identical to + the interrupts property of the parent node) - interrupt-parent : optional, if needed for interrupt mapping Example: @@ -70,30 +67,27 @@ Example: }; }; -* Freescale 85xx/86xx DMA Controller - -Freescale PowerPC 85xx/86xx have on chip general purpose DMA controllers. +** Freescale EloPlus DMA Controller + This is a 4-channel DMA controller with extended addresses and chaining, + mainly used in Freescale mpc85xx/86xx, Pxxx and BSC series chips, such as + mpc8540, mpc8641 p4080, bsc9131 etc. Required properties: -- compatible : compatible list, contains 2 entries, first is - "fsl,CHIP-dma", where CHIP is the processor - (mpc8540, mpc8540, etc.) and the second is - "fsl,eloplus-dma" -- reg : <registers mapping for DMA general status reg> +- compatible : must include "fsl,eloplus-dma" +- reg : DMA General Status Register, i.e. DGSR which contains + status for all the 4 DMA channels - cell-index : controller index. 0 for controller @ 0x21000, 1 for controller @ 0xc000 -- ranges : Should be defined as specified in 1) to describe the - DMA controller channels. +- ranges : describes the mapping between the address space of the + DMA channels and the address space of the DMA controller - DMA channel nodes: - - compatible : compatible list, contains 2 entries, first is - "fsl,CHIP-dma-channel", where CHIP is the processor - (mpc8540, mpc8560, etc.) and the second is - "fsl,eloplus-dma-channel". However, see note below. - - cell-index : dma channel index starts at 0. - - reg : <registers mapping for channel> - - interrupts : <interrupt mapping for DMA channel IRQ> + - compatible : must include "fsl,eloplus-dma-channel" + However, see note below. + - cell-index : DMA channel index starts at 0. + - reg : DMA channel specific registers + - interrupts : interrupt specifier for DMA channel IRQ - interrupt-parent : optional, if needed for interrupt mapping Example: @@ -134,6 +128,76 @@ Example: }; }; +** Freescale Elo3 DMA Controller + DMA controller which has same function as EloPlus except that Elo3 has 8 + channels while EloPlus has only 4, it is used in Freescale Txxx and Bxxx + series chips, such as t1040, t4240, b4860. + +Required properties: + +- compatible : must include "fsl,elo3-dma" +- reg : contains two entries for DMA General Status Registers, + i.e. DGSR0 which includes status for channel 1~4, and + DGSR1 for channel 5~8 +- ranges : describes the mapping between the address space of the + DMA channels and the address space of the DMA controller + +- DMA channel nodes: + - compatible : must include "fsl,eloplus-dma-channel" + - reg : DMA channel specific registers + - interrupts : interrupt specifier for DMA channel IRQ + - interrupt-parent : optional, if needed for interrupt mapping + +Example: +dma@100300 { + #address-cells = <1>; + #size-cells = <1>; + compatible = "fsl,elo3-dma"; + reg = <0x100300 0x4>, + <0x100600 0x4>; + ranges = <0x0 0x100100 0x500>; + dma-channel@0 { + compatible = "fsl,eloplus-dma-channel"; + reg = <0x0 0x80>; + interrupts = <28 2 0 0>; + }; + dma-channel@80 { + compatible = "fsl,eloplus-dma-channel"; + reg = <0x80 0x80>; + interrupts = <29 2 0 0>; + }; + dma-channel@100 { + compatible = "fsl,eloplus-dma-channel"; + reg = <0x100 0x80>; + interrupts = <30 2 0 0>; + }; + dma-channel@180 { + compatible = "fsl,eloplus-dma-channel"; + reg = <0x180 0x80>; + interrupts = <31 2 0 0>; + }; + dma-channel@300 { + compatible = "fsl,eloplus-dma-channel"; + reg = <0x300 0x80>; + interrupts = <76 2 0 0>; + }; + dma-channel@380 { + compatible = "fsl,eloplus-dma-channel"; + reg = <0x380 0x80>; + interrupts = <77 2 0 0>; + }; + dma-channel@400 { + compatible = "fsl,eloplus-dma-channel"; + reg = <0x400 0x80>; + interrupts = <78 2 0 0>; + }; + dma-channel@480 { + compatible = "fsl,eloplus-dma-channel"; + reg = <0x480 0x80>; + interrupts = <79 2 0 0>; + }; +}; + Note on DMA channel compatible properties: The compatible property must say "fsl,elo-dma-channel" or "fsl,eloplus-dma-channel" to be used by the Elo DMA driver (fsldma). Any DMA channel used by fsldma cannot be used by another diff --git a/Documentation/dmatest.txt b/Documentation/dmatest.txt index a2b5663eae26..dd77a81bdb80 100644 --- a/Documentation/dmatest.txt +++ b/Documentation/dmatest.txt @@ -15,39 +15,48 @@ be built as module or inside kernel. Let's consider those cases. Part 2 - When dmatest is built as a module... -After mounting debugfs and loading the module, the /sys/kernel/debug/dmatest -folder with nodes will be created. There are two important files located. First -is the 'run' node that controls run and stop phases of the test, and the second -one, 'results', is used to get the test case results. - -Note that in this case test will not run on load automatically. - Example of usage: + % modprobe dmatest channel=dma0chan0 timeout=2000 iterations=1 run=1 + +...or: + % modprobe dmatest % echo dma0chan0 > /sys/module/dmatest/parameters/channel % echo 2000 > /sys/module/dmatest/parameters/timeout % echo 1 > /sys/module/dmatest/parameters/iterations - % echo 1 > /sys/kernel/debug/dmatest/run + % echo 1 > /sys/module/dmatest/parameters/run + +...or on the kernel command line: + + dmatest.channel=dma0chan0 dmatest.timeout=2000 dmatest.iterations=1 dmatest.run=1 Hint: available channel list could be extracted by running the following command: % ls -1 /sys/class/dma/ -After a while you will start to get messages about current status or error like -in the original code. +Once started a message like "dmatest: Started 1 threads using dma0chan0" is +emitted. After that only test failure messages are reported until the test +stops. Note that running a new test will not stop any in progress test. -The following command should return actual state of the test. - % cat /sys/kernel/debug/dmatest/run - -To wait for test done the user may perform a busy loop that checks the state. - - % while [ $(cat /sys/kernel/debug/dmatest/run) = "Y" ] - > do - > echo -n "." - > sleep 1 - > done - > echo +The following command returns the state of the test. + % cat /sys/module/dmatest/parameters/run + +To wait for test completion userpace can poll 'run' until it is false, or use +the wait parameter. Specifying 'wait=1' when loading the module causes module +initialization to pause until a test run has completed, while reading +/sys/module/dmatest/parameters/wait waits for any running test to complete +before returning. For example, the following scripts wait for 42 tests +to complete before exiting. Note that if 'iterations' is set to 'infinite' then +waiting is disabled. + +Example: + % modprobe dmatest run=1 iterations=42 wait=1 + % modprobe -r dmatest +...or: + % modprobe dmatest run=1 iterations=42 + % cat /sys/module/dmatest/parameters/wait + % modprobe -r dmatest Part 3 - When built-in in the kernel... @@ -62,21 +71,22 @@ case. You always could check them at run-time by running Part 4 - Gathering the test results -The module provides a storage for the test results in the memory. The gathered -data could be used after test is done. +Test results are printed to the kernel log buffer with the format: -The special file 'results' in the debugfs represents gathered data of the in -progress test. The messages collected are printed to the kernel log as well. +"dmatest: result <channel>: <test id>: '<error msg>' with src_off=<val> dst_off=<val> len=<val> (<err code>)" Example of output: - % cat /sys/kernel/debug/dmatest/results - dma0chan0-copy0: #1: No errors with src_off=0x7bf dst_off=0x8ad len=0x3fea (0) + % dmesg | tail -n 1 + dmatest: result dma0chan0-copy0: #1: No errors with src_off=0x7bf dst_off=0x8ad len=0x3fea (0) The message format is unified across the different types of errors. A number in the parens represents additional information, e.g. error code, error counter, -or status. +or status. A test thread also emits a summary line at completion listing the +number of tests executed, number that failed, and a result code. -Comparison between buffers is stored to the dedicated structure. +Example: + % dmesg | tail -n 1 + dmatest: dma0chan0-copy0: summary 1 test, 0 failures 1000 iops 100000 KB/s (0) -Note that the verify result is now accessible only via file 'results' in the -debugfs. +The details of a data miscompare error are also emitted, but do not follow the +above format. |