[Skiboot] [PATCH v2 7/9] prd: Implement generic HBRT - FSP interface

[Vasant Hegde]

On 05/06/2019 03:19 PM, Jeremy Kerr wrote:
> Hi Vasant,
> 
>> Also introduces new opal_msg type (OPAL_MSG_PRD2) to pass bigger prd
>> message
>> to kernel.
>>    - if (prd_msg > OPAL_MSG_FIXED_PARAMS_SIZE)
>> 	use OPAL_MSG_PRD2
> 
> Why make it conditional? Can't we use the PRD2 interface for small
> messages too?

.. So that it can work with old kernel as well. Hence I added this check.

> 
>> +struct prd_fw_mbox_msg {
>> +	__be32	msgq;		/* ex: MBOX::FSP_VPD_MSGQ */
>> +	__be32	msg_type;	/* ex: VPD_MSG_TYPE:VPD_WRITE_PROC */
>> +	struct {
>> +		__be32	async:1;
>> +		__be32	pseudosync:1;
>> +		__be32	unused:30;
>> +	};
> 
> Are you expecting all compilers to lay these bitfields out in a
> consistent format?

This is hostboot defined structure. This is directly passed by HBRT to FSP.
We are not using it. Just for completeness purpose I have defined this structure.

-Vasant