Re: [PATCH v7 05/45] arm64: RME: Add wrappers for RMI calls

Gavin Shan
2025-03-03T03:42:51Z

On 2/14/25 2:13 AM, Steven Price wrote:
> The wrappers make the call sites easier to read and deal with the
> boiler plate of handling the error codes from the RMM.
>
> Signed-off-by: Steven Price <steven.price@arm.com>
> ---
> Changes from v5:
> * Further improve comments
> Changes from v4:
> * Improve comments
> Changes from v2:
> * Make output arguments optional.
> * Mask RIPAS value rmi_rtt_read_entry()
> * Drop unused rmi_rtt_get_phys()
> ---
> arch/arm64/include/asm/rmi_cmds.h | 508 ++++++++++++++++++++++++++++++
> 1 file changed, 508 insertions(+)
> create mode 100644 arch/arm64/include/asm/rmi_cmds.h
>

With the following nitpicks addressed:

Reviewed-by: Gavin Shan <gshan@redhat.com>

> diff --git a/arch/arm64/include/asm/rmi_cmds.h b/arch/arm64/include/asm/rmi_cmds.h
> new file mode 100644
> index 000000000000..043b7ff278ee
> --- /dev/null
> +++ b/arch/arm64/include/asm/rmi_cmds.h
> @@ -0,0 +1,508 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2023 ARM Ltd.
> + */
> +
> +#ifndef __ASM_RMI_CMDS_H
> +#define __ASM_RMI_CMDS_H
> +

[...]

> +
> +/**
> + * rmi_rec_aux_count() - Get number of auxiliary granules required
> + * @rd: PA of the RD
> + * @aux_count: Number of pages written to this pointer
^^^^^^^^^^^^^^^
Number of granules
> + *
> + * A REC may require extra auxiliary pages to be delegated for the RMM to
^^^^^
granules

> + * store metadata (not visible to the normal world) in. This function provides
> + * the number of pages that are required.
^^^^^
granules
> + *
> + * Return: RMI return code
> + */
> +static inline int rmi_rec_aux_count(unsigned long rd, unsigned long *aux_count)
> +{
> + struct arm_smccc_res res;
> +
> + arm_smccc_1_1_invoke(SMC_RMI_REC_AUX_COUNT, rd, &res);
> +
> + if (aux_count)
> + *aux_count = res.a1;
> + return res.a0;
> +}
> +
> +/**
> + * rmi_rec_create() - Create a REC
> + * @rd: PA of the RD
> + * @rec: PA of the target REC
> + * @params_ptr: PA of REC parameters
> + *
> + * Create a REC using the parameters specified in the struct rec_params pointed
> + * to by @params_ptr.
> + *
> + * Return: RMI return code
> + */
> +static inline int rmi_rec_create(unsigned long rd, unsigned long rec,
> + unsigned long params_ptr)
> +{
> + struct arm_smccc_res res;
> +
> + arm_smccc_1_1_invoke(SMC_RMI_REC_CREATE, rd, rec, params_ptr, &res);
> +
> + return res.a0;
> +}
> +

'params_ptr' may be renamed to 'params'.

[...]
> +#endif /* __ASM_RMI_CMDS_H */

Thanks,
Gavin