David, On 28/11/18 17:42, David Lechner wrote: > On 11/27/18 9:15 AM, Roger Quadros wrote: >> >> On 26/11/18 23:14, David Lechner wrote: >>> On 11/22/18 5:38 AM, Roger Quadros wrote: >>>> From: Suman Anna <s-anna@xxxxxx> >>>> >>>> This patch adds the bindings for the Programmable Real-Time Unit >>>> and Industrial Communication Subsystem (PRU-ICSS) present on various >>>> TI SoCs. The IP is present on multiple TI SoC architecture families >>>> including the OMAP architecture SoCs such as AM33xx, AM437x and >>>> AM57xx; and on a Keystone 2 architecture based 66AK2G SoC. It is >>>> also present on the Davinci based OMAPL138 SoCs and K3 architecture >>>> based AM65x SoCs as well (not covered for now). Details have been >>>> added to include bindings for various core sub-modules like the PRU >>>> Cores, the PRUSS Interrupt Controller, and other sub-modules used >>>> for Industrial Communication purposes, covering the MDIO, MII_RT >>>> and the IEP sub-modules. The binding mostly uses standard DT >>>> properties. >>>> >>>> Signed-off-by: Suman Anna <s-anna@xxxxxx> >>>> Signed-off-by: Roger Quadros <rogerq@xxxxxx> >>>> --- >>>> .../devicetree/bindings/soc/ti/ti,pruss.txt | 360 +++++++++++++++++++++ >>>> 1 file changed, 360 insertions(+) >>>> create mode 100644 Documentation/devicetree/bindings/soc/ti/ti,pruss.txt >>>> >>>> diff --git a/Documentation/devicetree/bindings/soc/ti/ti,pruss.txt b/Documentation/devicetree/bindings/soc/ti/ti,pruss.txt >>>> new file mode 100644 >>>> index 0000000..24fedad >>>> --- /dev/null >>>> +++ b/Documentation/devicetree/bindings/soc/ti/ti,pruss.txt >>> >>> ... >>> >>>> + >>>> +PRU-ICSS SoC Bus Parent Node >>>> +============================= >>>> +This node represents the integration of the PRU-ICSS IP into a SoC, and is >>>> +required for all SoCs. The PRU-ICSS parent nodes need to be defined as child >>>> +nodes of this node. >>>> + >>>> +Required Properties: >>>> +-------------------- >>>> +- compatible : should be one of, >>>> + "ti,am3356-pruss-soc-bus" for AM335x family of SoCs >>>> + "ti,am4376-pruss-soc-bus" for AM437x family of SoCs >>>> + "ti,am5728-pruss-soc-bus" for AM57xx family of SoCs >>>> + "ti,k2g-pruss-soc-bus" for 66AK2G family of SoCs >>>> +- reg : address and size of the PRUSS CFG sub-module registers >>>> + dictating the interconnect configuration >>> >>> I haven't looked into Tony's suggestion of using ti-sysc yet, so this may be a >>> moot point, but how will this work with AM18xx that does not have a PRUSS CFG >>> register? It seems to me that reg here should be the address and size of the >>> entire PRUSS IP block and the CFG register should be a syscon node or something >>> like that. >> >> The reg property description is incorrect in the patch. It should have been >> >> reg : address of SYSCFG register. >> >> The SYSCFG register is used to enable and reset the module. >> >> But based on Tony's suggestion this wrapper driver will change to ti,sysc for >> OMAP like SoCs. >> >> For AM18xx it could be a simple wrapper driver that just populates the children? > > I suppose that could work. I will look into it (perhaps after seeing what you > come up with in v2). > >> >>> >>>> +- #address-cells : should be 1 >>>> +- #size-cells : should be 1 >>>> +- ranges : standard ranges definition >>>> + >>> >>> ... >>> >>>> + >>>> +PRUSS INTC Child Node >>>> +====================== >>>> +Each PRUSS has a single interrupt controller instance that is common to both >>>> +the PRU cores. Each interrupt controller can detect 64 input events which are >>>> +then mapped to 10 possible output interrupts through two levels of mapping. The >>>> +input events can be triggered by either the PRUs and/or various other PRUSS >>>> +internal and external peripherals. The first 2 output interrupts are fed >>>> +exclusively to the internal PRU cores, with the remaining 8 connected to >>>> +external interrupt controllers including the MPU. >>> >>> FYI, on AM18xx, there is a PRUSSEVTSEL bit in CFGCHIP3[3] (already a syscon node >>> in the device tree) that allows selecting one of two groups of 32 input events >>> out of this group of 64. This is perhaps getting out of the scope of this patch >>> series, but I just want to make sure we end up with something that can be easily >>> extended for this case. For example, I was thinking that this binding could be >>> modified so that #interrupt-cells could be 1 or 2. If it is 2, then the first >>> cell specifies the PRUSSEVTSEL value and the second value is the event number. >>> >> >> this is da850.dtsi correct? > > Yes. > >> >> As PRUSSEVTSEL is not SYSEVENT specific but applies to all the SYSEVENTs at a time. >> I don't think interrupt-cells is the right place to specify this. >> >> Can it be set in DT in the board file? But this can't change once booted so maybe restrictive. > > I guess the way I see this is that it is like specifying the bank and index for > a GPIO. If you only specify the system event number, then it is not clear which > event you mean - it could be one of two events. You have to also specify the > PRUSSEVTSEL value (one could call this the bank or group, I suppose) to fully > describe the system event. But this PRUSSEVTSEL is not present on most SoCs. I think it is only on the AM18xx and OMAP-L13x SoCs. How about modelling this as a linear map of 64 events and decode this internally in INTC driver. i.e. 0 to 31 set PRUSSEVTSEL to 0 and 32 to 63 set PRUSSEVTSEL to 1. If any interrupt map provides sysevents from both groups simultaneously then we complain and error out. This should keep the dt-binding and resource table format identical across all SoCs. > >> >> If runtime change is required it can only be done before a PRU boots. >> >> How about providing this info in the resource table and/or application DT node? > > This seems like this would make it easy to end up with a broken interrupts > if you accidentally try to use interrupts from both groups. Instead this > could be implemented in the irqchip driver such that the first interrupt > (system event) requested gets to select the group. If any interrupts from > the other group are requested later, they can just return an error. Any > interrupts in the same group as the first can be requested successfully. cheers, -roger -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
