[PATCH v6 01/11] arm64: rsi: Add RSI definitions
Gavin Shan
gshan at redhat.com
Mon Oct 7 16:08:18 PDT 2024
On 10/5/24 12:42 AM, Steven Price wrote:
> From: Suzuki K Poulose <suzuki.poulose at arm.com>
>
> The RMM (Realm Management Monitor) provides functionality that can be
> accessed by a realm guest through SMC (Realm Services Interface) calls.
>
> The SMC definitions are based on DEN0137[1] version 1.0-rel0.
>
> [1] https://developer.arm.com/documentation/den0137/1-0rel0/
>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose at arm.com>
> Acked-by: Catalin Marinas <catalin.marinas at arm.com>
> Reviewed-by: Gavin Shan <gshan at redht.com>
> Signed-off-by: Steven Price <steven.price at arm.com>
> ---
[...]
> +
> +static inline unsigned long rsi_set_addr_range_state(phys_addr_t start,
> + phys_addr_t end,
> + enum ripas state,
> + unsigned long flags,
> + phys_addr_t *top)
> +{
> + struct arm_smccc_res res;
> +
> + arm_smccc_smc(SMC_RSI_IPA_STATE_SET, start, end, state,
> + flags, 0, 0, 0, &res);
> +
> + if (top)
> + *top = res.a1;
> +
> + if (res.a2 != RSI_ACCEPT)
> + return -EPERM;
> +
> + return res.a0;
> +}
> +
Similar to rsi_attestation_token_init(), the return value type needs to be 'long'
since '-EPERM' can be returned from the function.
> +/**
> + * rsi_attestation_token_init - Initialise the operation to retrieve an
> + * attestation token.
> + *
> + * @challenge: The challenge data to be used in the attestation token
> + * generation.
> + * @size: Size of the challenge data in bytes.
> + *
> + * Initialises the attestation token generation and returns an upper bound
> + * on the attestation token size that can be used to allocate an adequate
> + * buffer. The caller is expected to subsequently call
> + * rsi_attestation_token_continue() to retrieve the attestation token data on
> + * the same CPU.
> + *
> + * Returns:
> + * On success, returns the upper limit of the attestation report size.
> + * Otherwise, -EINVAL
> + */
> +static inline long
> +rsi_attestation_token_init(const u8 *challenge, unsigned long size)
> +{
> + struct arm_smccc_1_2_regs regs = { 0 };
> +
> + /* The challenge must be at least 32bytes and at most 64bytes */
> + if (!challenge || size < 32 || size > 64)
> + return -EINVAL;
> +
> + regs.a0 = SMC_RSI_ATTESTATION_TOKEN_INIT;
> + memcpy(®s.a1, challenge, size);
> + arm_smccc_1_2_smc(®s, ®s);
> +
> + if (regs.a0 == RSI_SUCCESS)
> + return regs.a1;
> +
> + return -EINVAL;
> +}
> +
> +/**
> + * rsi_attestation_token_continue - Continue the operation to retrieve an
> + * attestation token.
> + *
> + * @granule: {I}PA of the Granule to which the token will be written.
> + * @offset: Offset within Granule to start of buffer in bytes.
> + * @size: The size of the buffer.
> + * @len: The number of bytes written to the buffer.
> + *
> + * Retrieves up to a RSI_GRANULE_SIZE worth of token data per call. The caller
> + * is expected to call rsi_attestation_token_init() before calling this
> + * function to retrieve the attestation token.
> + *
> + * Return:
> + * * %RSI_SUCCESS - Attestation token retrieved successfully.
> + * * %RSI_INCOMPLETE - Token generation is not complete.
> + * * %RSI_ERROR_INPUT - A parameter was not valid.
> + * * %RSI_ERROR_STATE - Attestation not in progress.
> + */
> +static inline int rsi_attestation_token_continue(phys_addr_t granule,
> + unsigned long offset,
> + unsigned long size,
> + unsigned long *len)
> +{
> + struct arm_smccc_res res;
> +
> + arm_smccc_1_1_invoke(SMC_RSI_ATTESTATION_TOKEN_CONTINUE,
> + granule, offset, size, 0, &res);
> +
> + if (len)
> + *len = res.a1;
> + return res.a0;
> +}
> +
The return value type of this function needs to be 'unsigned long' even it's
converted to 'int' in arm_cca_attestation_continue(). In this way, the wrapper
functions has consistent return value type, which is 'unsigned long' or 'long'.
Thanks,
Gavin
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