Re: [PATCH 01/17] dt-bindings: remoteproc: Add OMAP remoteproc bindings

[Rob Herring <robh@kernel.org>]

On Mon, Oct 28, 2019 at 02:42:22PM +0200, Tero Kristo wrote:
> From: Suman Anna <s-anna@ti.com>
> 
> Add the device tree bindings document for the IPU and DSP
> remote processor devices on OMAP4+ SoCs.
> 
> Cc: Rob Herring <robh@kernel.org>
> Cc: devicetree@vger.kernel.org
> Signed-off-by: Suman Anna <s-anna@ti.com>
> Signed-off-by: Tero Kristo <t-kristo@ti.com>
> ---
>  .../remoteproc/ti,omap-remoteproc.txt         | 205 ++++++++++++++++++
>  1 file changed, 205 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/remoteproc/ti,omap-remoteproc.txt
>

Looks to be in pretty good shape, but how about doing a schema.

> diff --git a/Documentation/devicetree/bindings/remoteproc/ti,omap-remoteproc.txt b/Documentation/devicetree/bindings/remoteproc/ti,omap-remoteproc.txt
> new file mode 100644
> index 000000000000..e2bcfcab21c1
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/remoteproc/ti,omap-remoteproc.txt
> @@ -0,0 +1,205 @@
> +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

ti,bootreg

> +			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

From the mboxes description, seemed like only one entry?

Need to define the values here.

> +
> +- 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.

These 2 are not standard names. Either need 'ti,' prefix or we should 
standardize them. There's been some discussion of an input capture 
binding and I was wondering if it should be more general to any 
timer function.

> +
> +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>;
> +		};
> +	};
> -- 
> 2.17.1
> 
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