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+OMAP4+ Remoteproc Devices
+=========================
+
+The OMAP family of SoCs usually have one or more slave processor sub-systems
+that are used to offload some of the processor-intensive tasks, or to manage
+other hardware accelerators, for achieving various system level goals.
+
+The processor cores in the sub-system are usually behind an IOMMU, and may
+contain additional sub-modules like Internal RAM and/or ROMs, L1 and/or L2
+caches, an Interrupt Controller, a Cache Controller etc.
+
+The OMAP SoCs usually have a DSP processor sub-system and/or an IPU processor
+sub-system. The DSP processor sub-system can contain any of the TI's C64x,
+C66x or C67x family of DSP cores as the main execution unit. The IPU processor
+sub-system usually contains either a Dual-Core Cortex-M3 or Dual-Core Cortex-M4
+processors.
+
+Remote Processor Node:
+======================
+Each remote processor sub-system is represented as a single DT node. Each node
+has a number of required or optional properties that enable the OS running on
+the host processor (MPU) to perform the device management of the remote
+processor and to communicate with the remote processor. The various properties
+can be classified as constant or variable. The constant properties are dictated
+by the SoC and does not change from one board to another having the same SoC.
+Examples of constant properties include 'iommus', 'reg'. The variable properties
+are dictated by the system integration aspects such as memory on the board, or
+configuration used within the corresponding firmware image. Examples of variable
+properties include 'mboxes', 'memory-region', 'timers', 'watchdog-timers' etc.
+
+Required properties:
+--------------------
+The following are the mandatory properties:
+
+- compatible: Should be one of the following,
+ "ti,omap4-dsp" for DSPs on OMAP4 SoCs
+ "ti,omap5-dsp" for DSPs on OMAP5 SoCs
+ "ti,dra7-dsp" for DSPs on DRA7xx/AM57xx SoCs
+ "ti,omap4-ipu" for IPUs on OMAP4 SoCs
+ "ti,omap5-ipu" for IPUs on OMAP5 SoCs
+ "ti,dra7-ipu" for IPUs on DRA7xx/AM57xx SoCs
+
+- iommus: phandles to OMAP IOMMU nodes, that need to be programmed
+ for this remote processor to access any external RAM memory or
+ other peripheral device address spaces. This property usually
+ has only a single phandle. Multiple phandles are used only in
+ cases where the sub-system has different ports for different
+ sub-modules within the processor sub-system (eg: DRA7 DSPs),
+ and need the same programming in both the MMUs.
+
+- mboxes: OMAP Mailbox specifier denoting the sub-mailbox, to be used for
+ communication with the remote processor. The specifier format is
+ as per the bindings,
+ Documentation/devicetree/bindings/mailbox/omap-mailbox.txt
+ This property should match with the sub-mailbox node used in
+ the firmware image.
+
+Optional properties:
+--------------------
+Some of these properties are mandatory on some SoCs, and some are optional
+depending on the configuration of the firmware image to be executed on the
+remote processor. The conditions are mentioned for each property.
+
+The following are the optional properties:
+- reg: Address space for any remoteproc memories present on
+ the SoC. Should contain an entry for each value in
+ 'reg-names'. These are mandatory for all DSP and IPU
+ processors that have them (OMAP4/OMAP5 DSPs do not have
+ any RAMs)
+
+- reg-names: Required names for each of the address spaces defined in
+ the 'reg' property. Should contain a string from among
+ the following names, each representing the corresponding
+ internal RAM memory region,
+ "l2ram" for L2 RAM,
+ "l1pram" for L1 Program RAM Memory/Cache,
+ "l1dram" for L1 Data RAM Memory/Cache,
+
+ All devices may not have all the above memories.
+
+- syscon-bootreg: Should be a pair of the phandle to the System Control
+ Configuration region that contains the boot address
+ register, and the register offset of the boot address
+ register within the System Control module. This property
+ is required for all the DSP instances on OMAP4, OMAP5
+ and DRA7xx SoCs.
+
+- memory-region: phandle to the reserved memory node to be associated
+ with the remoteproc device. The reserved memory node
+ can be a CMA memory node, and should be defined as
+ per the bindings,
+ Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
+
+- mbox-names: Optional names for the OMAP mailbox specifiers mentioned
+ in the 'mboxes' property, one per specifier value
+
+- timers: One or more phandles to OMAP DMTimer nodes, that serve
+ as System/Tick timers for the OS running on the remote
+ processors. This will usually be a single timer if the
+ processor sub-system is running in SMP mode, or one per
+ core in the processor sub-system. This can also be used
+ to reserve specific timers to be dedicated to the
+ remote processors.
+
+ This property is mandatory on remote processors requiring
+ external tick wakeup, and to support Power Management
+ features. The timers to be used should match with the
+ timers used in the firmware image.
+
+- watchdog-timers: One or more phandles to OMAP DMTimer nodes, used to
+ serve as Watchdog timers for the processor cores. This
+ will usually be one per executing processor core, even
+ if the processor sub-system is running a SMP OS.
+
+ The timers to be used should match with the watchdog
+ timers used in the firmware image.
+
+Example:
+--------
+
+1. OMAP4 DSP
+ /* DSP Reserved Memory node */
+ reserved-memory {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+
+ dsp_memory_region: dsp-memory@98000000 {
+ compatible = "shared-dma-pool";
+ reg = <0x98000000 0x800000>;
+ reusable;
+ };
+ };
+
+ /* DSP node */
+ ocp {
+ dsp: dsp {
+ compatible = "ti,omap4-dsp";
+ syscon-bootreg = <&scm_conf 0x304>;
+ iommus = <&mmu_dsp>;
+ mboxes = <&mailbox &mbox_dsp>;
+ memory-region = <&dsp_memory_region>;
+ timers = <&timer5>;
+ watchdog-timers = <&timer6>;
+ };
+ };
+
+2. OMAP5 IPU
+ /* IPU Reserved Memory node */
+ reserved-memory {
+ #address-cells = <2>;
+ #size-cells = <2>;
+ ranges;
+
+ ipu_memory_region: ipu-memory@95800000 {
+ compatible = "shared-dma-pool";
+ reg = <0 0x95800000 0 0x3800000>;
+ reusable;
+ };
+ };
+
+ /* IPU node */
+ ocp {
+ ipu: ipu@55020000 {
+ compatible = "ti,omap5-ipu";
+ reg = <0x55020000 0x10000>;
+ reg-names = "l2ram";
+ iommus = <&mmu_ipu>;
+ mboxes = <&mailbox &mbox_ipu>;
+ memory-region = <&ipu_memory_region>;
+ timers = <&timer3>, <&timer4>;
+ watchdog-timers = <&timer9>, <&timer11>;
+ };
+ };
+
+3. DRA7xx/AM57xx DSP
+ /* DSP1 Reserved Memory node */
+ reserved-memory {
+ #address-cells = <2>;
+ #size-cells = <2>;
+ ranges;
+
+ dsp1_memory_region: dsp1-memory@99000000 {
+ compatible = "shared-dma-pool";
+ reg = <0x0 0x99000000 0x0 0x4000000>;
+ reusable;
+ };
+ };
+
+ /* DSP1 node */
+ ocp {
+ dsp1: dsp@40800000 {
+ compatible = "ti,dra7-dsp";
+ reg = <0x40800000 0x48000>,
+ <0x40e00000 0x8000>,
+ <0x40f00000 0x8000>;
+ reg-names = "l2ram", "l1pram", "l1dram";
+ syscon-bootreg = <&scm_conf 0x55c>;
+ iommus = <&mmu0_dsp1>, <&mmu1_dsp1>;
+ mboxes = <&mailbox5 &mbox_dsp1_ipc3x>;
+ memory-region = <&dsp1_memory_region>;
+ timers = <&timer5>;
+ watchdog-timers = <&timer10>;
+ };
+ };