summaryrefslogtreecommitdiff
path: root/Documentation/devicetree/bindings/soc/ti/keystone-navigator-dma.txt
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/devicetree/bindings/soc/ti/keystone-navigator-dma.txt')
-rw-r--r--Documentation/devicetree/bindings/soc/ti/keystone-navigator-dma.txt111
1 files changed, 111 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/soc/ti/keystone-navigator-dma.txt b/Documentation/devicetree/bindings/soc/ti/keystone-navigator-dma.txt
new file mode 100644
index 000000000000..337c4ea5c57b
--- /dev/null
+++ b/Documentation/devicetree/bindings/soc/ti/keystone-navigator-dma.txt
@@ -0,0 +1,111 @@
+Keystone Navigator DMA Controller
+
+This document explains the device tree bindings for the packet dma
+on keystone devices. The Keystone Navigator DMA driver sets up the dma
+channels and flows for the QMSS(Queue Manager SubSystem) who triggers
+the actual data movements across clients using destination queues. Every
+client modules like NETCP(Network Coprocessor), SRIO(Serial Rapid IO),
+CRYPTO Engines etc has its own instance of dma hardware. QMSS has also
+an internal packet DMA module which is used as an infrastructure DMA
+with zero copy.
+
+Navigator DMA cloud layout:
+ ------------------
+ | Navigator DMAs |
+ ------------------
+ |
+ |-> DMA instance #0
+ |
+ |-> DMA instance #1
+ .
+ .
+ |
+ |-> DMA instance #n
+
+Navigator DMA properties:
+Required properties:
+ - compatible: Should be "ti,keystone-navigator-dma"
+ - clocks: phandle to dma instances clocks. The clock handles can be as
+ many as the dma instances. The order should be maintained as per
+ the dma instances.
+ - ti,navigator-cloud-address: Should contain base address for the multi-core
+ navigator cloud and number of addresses depends on SOC integration
+ configuration.. Navigator cloud global address needs to be programmed
+ into DMA and the DMA uses it as the physical addresses to reach queue
+ managers. Note that these addresses though points to queue managers,
+ they are relevant only from DMA perspective. The QMSS may not choose to
+ use them since it has a different address space view to reach all
+ its components.
+
+DMA instance properties:
+Required properties:
+ - reg: Should contain register location and length of the following dma
+ register regions. Register regions should be specified in the following
+ order.
+ - Global control register region (global).
+ - Tx DMA channel configuration register region (txchan).
+ - Rx DMA channel configuration register region (rxchan).
+ - Tx DMA channel Scheduler configuration register region (txsched).
+ - Rx DMA flow configuration register region (rxflow).
+
+Optional properties:
+ - reg-names: Names for the register regions.
+ - ti,enable-all: Enable all DMA channels vs clients opening specific channels
+ what they need. This property is useful for the userspace fast path
+ case where the linux drivers enables the channels used by userland
+ stack.
+ - ti,loop-back: To loopback Tx streaming I/F to Rx streaming I/F. Used for
+ infrastructure transfers.
+ - ti,rx-retry-timeout: Number of dma cycles to wait before retry on buffer
+ starvation.
+
+Example:
+
+ knav_dmas: knav_dmas@0 {
+ compatible = "ti,keystone-navigator-dma";
+ clocks = <&papllclk>, <&clkxge>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+ ti,navigator-cloud-address = <0x23a80000 0x23a90000
+ 0x23aa0000 0x23ab0000>;
+
+ dma_gbe: dma_gbe@0 {
+ reg = <0x2004000 0x100>,
+ <0x2004400 0x120>,
+ <0x2004800 0x300>,
+ <0x2004c00 0x120>,
+ <0x2005000 0x400>;
+ reg-names = "global", "txchan", "rxchan",
+ "txsched", "rxflow";
+ };
+
+ dma_xgbe: dma_xgbe@0 {
+ reg = <0x2fa1000 0x100>,
+ <0x2fa1400 0x200>,
+ <0x2fa1800 0x200>,
+ <0x2fa1c00 0x200>,
+ <0x2fa2000 0x400>;
+ reg-names = "global", "txchan", "rxchan",
+ "txsched", "rxflow";
+ };
+ };
+
+Navigator DMA client:
+Required properties:
+ - ti,navigator-dmas: List of one or more DMA specifiers, each consisting of
+ - A phandle pointing to DMA instance node
+ - A DMA channel number as a phandle arg.
+ - ti,navigator-dma-names: Contains dma channel name for each DMA specifier in
+ the 'ti,navigator-dmas' property.
+
+Example:
+
+ netcp: netcp@2090000 {
+ ..
+ ti,navigator-dmas = <&dma_gbe 22>,
+ <&dma_gbe 23>,
+ <&dma_gbe 8>;
+ ti,navigator-dma-names = "netrx0", "netrx1", "nettx";
+ ..
+ };