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Date:   Wed, 19 Oct 2022 13:48:48 -0500
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Subject: Re: [PATCH Part2 v6 12/49] crypto: ccp: Add support to initialize the
 AMD-SP for SEV-SNP
Content-Language: en-US
From:   "Kalra, Ashish" <ashish.kalra@amd.com>
To:     Borislav Petkov <bp@alien8.de>
Cc:     x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        linux-coco@lists.linux.dev, linux-mm@kvack.org,
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Another follow up:

>>>   int sev_platform_init(int *error);
>>> +/**
>>> + * sev_snp_init - perform SEV SNP_INIT command
>>> + *
>>> + * @error: SEV command return code
>>> + *
>>> + * Returns:
>>> + * 0 if the SEV successfully processed the command
>>> + * -%ENODEV    if the SEV device is not available
>>> + * -%ENOTSUPP  if the SEV does not support SEV
>>> + * -%ETIMEDOUT if the SEV command timed out
>>> + * -%EIO       if the SEV returned a non-zero return code
>>
>> Something's weird with those args. I think it should be
>>
>>     %-ENODEV
>>
>> and so on...
>>
> 
> Yes, off course %-<errno>
> 

I see that other drivers are also using the same convention:

include/linux/regset.h:
..
/**
  * user_regset_set_fn - type of @set function in &struct user_regset
  * @target:     thread being examined
  * @regset:     regset being examined
  * @pos:        offset into the regset data to access, in bytes
  * @count:      amount of data to copy, in bytes
  * @kbuf:       if not %NULL, a kernel-space pointer to copy from
  * @ubuf:       if @kbuf is %NULL, a user-space pointer to copy from
  *
  * Store register values.  Return %0 on success; -%EIO or -%ENODEV
  * are usual failure returns.  The @pos and @count values are in
...

include/linux/psp-tee.h:
..
/**
  * psp_tee_process_cmd() - Process command in Trusted Execution Environment
  * @cmd_id:     TEE command ID (&enum tee_cmd_id)
  * @buf:        Command buffer for TEE processing. On success, is updated
  *              with the response
  * @len:        Length of command buffer in bytes
  * @status:     On success, holds the TEE command execution status
  *
  * This function submits a command to the Trusted OS for processing in the
  * TEE environment and waits for a response or until the command times out.
  *
  * Returns:
  * 0 if TEE successfully processed the command
  * -%ENODEV    if PSP device not available
  * -%EINVAL    if invalid input
  * -%ETIMEDOUT if TEE command timed out
  * -%EBUSY     if PSP device is not responsive
  */
...

Thanks,
Ashish