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-rw-r--r--Documentation/devicetree/bindings/dma/atmel-dma.txt2
-rw-r--r--Documentation/devicetree/bindings/powerpc/fsl/dma.txt138
-rw-r--r--Documentation/dmatest.txt72
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.