Re: [PATCH RFC 1/5] optee: riscv: add RPMI TEE service group transport

[Amirreza Zarrabi]

Hi Trilok,

On 9/16/2026 3:30 PM, Trilok Soni wrote:
> On 9/12/2026 3:15 AM, Amirreza Zarrabi wrote:
>> Add an OP-TEE transport for RISC-V using the RPMI TEE service group over
>> the SBI MPXY mailbox framework.
>>
>> Request one mailbox channel per hart and use the channel corresponding to
>> the current CPU when issuing a TEE request. Probe the RPMI TEE service
>> group and required memory-sharing capabilities before registering the
>> transport.
>>
>> This provides the basic transport and discovery support needed by the
>> following patches.
>>
>> Signed-off-by: Amirreza Zarrabi <amirreza.zarrabi@xxxxxxxxxxxxxxxx>
>> ---
>>  drivers/tee/optee/Makefile                 |   1 +
>>  drivers/tee/optee/core.c                   |   8 +-
>>  drivers/tee/optee/optee_private.h          |  34 ++++
>>  drivers/tee/optee/optee_riscv.c            | 312 +++++++++++++++++++++++++++++
>>  drivers/tee/optee/optee_riscv.h            | 141 +++++++++++++
>>  include/linux/mailbox/riscv-rpmi-message.h |   1 +
>>  6 files changed, 495 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/tee/optee/Makefile b/drivers/tee/optee/Makefile
>> index ad7049c1c107..925b8ec7ef68 100644
>> --- a/drivers/tee/optee/Makefile
>> +++ b/drivers/tee/optee/Makefile
>> @@ -9,6 +9,7 @@ optee-objs += supp.o
>>  optee-objs += device.o
>>  optee-objs += smc_abi.o
>>  optee-objs += ffa_abi.o
>> +optee-$(CONFIG_RISCV_SBI_MPXY_MBOX) += optee_riscv.o
>>  
>>  # for tracing framework to find optee_trace.h
>>  CFLAGS_smc_abi.o := -I$(src)
>> diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
>> index a52c1f498b99..63f1725e646e 100644
>> --- a/drivers/tee/optee/core.c
>> +++ b/drivers/tee/optee/core.c
>> @@ -220,6 +220,7 @@ void optee_remove_common(struct optee *optee)
>>  
>>  static int smc_abi_rc;
>>  static int ffa_abi_rc;
>> +static int riscv_abi_rc;
>>  static bool intf_is_regged;
>>  
>>  static int __init optee_core_init(void)
>> @@ -245,9 +246,10 @@ static int __init optee_core_init(void)
>>  
>>  	smc_abi_rc = optee_smc_abi_register();
>>  	ffa_abi_rc = optee_ffa_abi_register();
>> +	riscv_abi_rc = optee_riscv_abi_register();
> 
> Isn't it growing rapidly now? We have two register calls for the ARM,
> one for the RISC-V. One more region specific ISA I am aware of and it
> may have op-tee support in future? It is time we fix this logic
> in the better way. 
>
> 
>>  
>> -	/* If both failed there's no point with this module */
>> -	if (smc_abi_rc && ffa_abi_rc) {
>> +	/* If all failed there's no point with this module */
>> +	if (smc_abi_rc && ffa_abi_rc && riscv_abi_rc) {
> 
> This is started looking ugly in my opinion. 
> 
>>  		if (IS_REACHABLE(CONFIG_RPMB)) {
>>  			rpmb_interface_unregister(&rpmb_class_intf);
>>  			intf_is_regged = false;
>> @@ -270,6 +272,8 @@ static void __exit optee_core_exit(void)
>>  		optee_smc_abi_unregister();
>>  	if (!ffa_abi_rc)
>>  		optee_ffa_abi_unregister();
>> +	if (!riscv_abi_rc)
>> +		optee_riscv_abi_unregister();
>>  }
>>  module_exit(optee_core_exit);
>>  
>> diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
>> index aefe1e6f5689..8d22d65e087b 100644
>> --- a/drivers/tee/optee/optee_private.h
>> +++ b/drivers/tee/optee/optee_private.h
>> @@ -171,6 +171,31 @@ struct optee_ffa {
>>  	struct work_struct notif_work;
>>  };
>>  
>> +/**
>> + * struct optee_riscv - RPMI TEE communication struct
> 
> do we need to name it optee_riscv? we don't use optee_arm anywhere in this
> code I believe. 
> 
> More later...
> 

The naming convention, and even the file structure, will change in v2.
This RFC currently mirrors the _internal_ FF-A implementation, which is neither
required nor ideal. We are moving away from that structure.

Best Regards,
Amir