Date:   Mon, 13 Feb 2023 18:43:34 +0200
From:   Zhi Wang <zhi.wang.linux@gmail.com>
To:     Steven Price <steven.price@arm.com>
Cc:     kvm@vger.kernel.org, kvmarm@lists.linux.dev,
        Catalin Marinas <catalin.marinas@arm.com>,
        Marc Zyngier <maz@kernel.org>, Will Deacon <will@kernel.org>,
        James Morse <james.morse@arm.com>,
        Oliver Upton <oliver.upton@linux.dev>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Zenghui Yu <yuzenghui@huawei.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Joey Gouly <joey.gouly@arm.com>,
        Alexandru Elisei <alexandru.elisei@arm.com>,
        Christoffer Dall <christoffer.dall@arm.com>,
        Fuad Tabba <tabba@google.com>, linux-coco@lists.linux.dev
Subject: Re: [RFC PATCH 03/28] arm64: RME: Add wrappers for RMI calls
Message-ID: <20230213184334.00007111@gmail.com>
In-Reply-To: <20230127112932.38045-4-steven.price@arm.com>
References: <20230127112248.136810-1-suzuki.poulose@arm.com>
        <20230127112932.38045-1-steven.price@arm.com>
        <20230127112932.38045-4-steven.price@arm.com>
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On Fri, 27 Jan 2023 11:29:07 +0000
Steven Price <steven.price@arm.com> 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>
> ---
>  arch/arm64/include/asm/rmi_cmds.h | 259 ++++++++++++++++++++++++++++++
>  1 file changed, 259 insertions(+)
>  create mode 100644 arch/arm64/include/asm/rmi_cmds.h
> 
> diff --git a/arch/arm64/include/asm/rmi_cmds.h b/arch/arm64/include/asm/rmi_cmds.h
> new file mode 100644
> index 000000000000..d5468ee46f35
> --- /dev/null
> +++ b/arch/arm64/include/asm/rmi_cmds.h
> @@ -0,0 +1,259 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2023 ARM Ltd.
> + */
> +
> +#ifndef __ASM_RMI_CMDS_H
> +#define __ASM_RMI_CMDS_H
> +
> +#include <linux/arm-smccc.h>
> +
> +#include <asm/rmi_smc.h>
> +
> +struct rtt_entry {
> +	unsigned long walk_level;
> +	unsigned long desc;
> +	int state;
> +	bool ripas;
> +};
> +

It would be nice to have some information of the follwoing wrappers. E.g.
meaning of the return value. They will be quite helpful in the later patch
review.

> +static inline int rmi_data_create(unsigned long data, unsigned long rd,
> +				  unsigned long map_addr, unsigned long src,
> +				  unsigned long flags)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_DATA_CREATE, data, rd, map_addr, src,
> +			     flags, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_data_create_unknown(unsigned long data,
> +					  unsigned long rd,
> +					  unsigned long map_addr)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_DATA_CREATE_UNKNOWN, data, rd, map_addr,
> +			     &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_data_destroy(unsigned long rd, unsigned long map_addr)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_DATA_DESTROY, rd, map_addr, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_features(unsigned long index, unsigned long *out)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_FEATURES, index, &res);
> +
> +	*out = res.a1;
> +	return res.a0;
> +}
> +
> +static inline int rmi_granule_delegate(unsigned long phys)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_GRANULE_DELEGATE, phys, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_granule_undelegate(unsigned long phys)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_GRANULE_UNDELEGATE, phys, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_psci_complete(unsigned long calling_rec,
> +				    unsigned long target_rec)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_PSCI_COMPLETE, calling_rec, target_rec,
> +			     &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_realm_activate(unsigned long rd)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_REALM_ACTIVATE, rd, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_realm_create(unsigned long rd, unsigned long params_ptr)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_REALM_CREATE, rd, params_ptr, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_realm_destroy(unsigned long rd)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_REALM_DESTROY, rd, &res);
> +
> +	return res.a0;
> +}
> +
> +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);
> +
> +	*aux_count = res.a1;
> +	return res.a0;
> +}
> +
> +static inline int rmi_rec_create(unsigned long rec, unsigned long rd,
> +				 unsigned long params_ptr)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_REC_CREATE, rec, rd, params_ptr, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_rec_destroy(unsigned long rec)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_REC_DESTROY, rec, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_rec_enter(unsigned long rec, unsigned long run_ptr)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_REC_ENTER, rec, run_ptr, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_rtt_create(unsigned long rtt, unsigned long rd,
> +				 unsigned long map_addr, unsigned long level)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_RTT_CREATE, rtt, rd, map_addr, level,
> +			     &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_rtt_destroy(unsigned long rtt, unsigned long rd,
> +				  unsigned long map_addr, unsigned long level)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_RTT_DESTROY, rtt, rd, map_addr, level,
> +			     &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_rtt_fold(unsigned long rtt, unsigned long rd,
> +			       unsigned long map_addr, unsigned long level)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_RTT_FOLD, rtt, rd, map_addr, level, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_rtt_init_ripas(unsigned long rd, unsigned long map_addr,
> +				     unsigned long level)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_RTT_INIT_RIPAS, rd, map_addr, level, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_rtt_map_unprotected(unsigned long rd,
> +					  unsigned long map_addr,
> +					  unsigned long level,
> +					  unsigned long desc)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_RTT_MAP_UNPROTECTED, rd, map_addr, level,
> +			     desc, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_rtt_read_entry(unsigned long rd, unsigned long map_addr,
> +				     unsigned long level, struct rtt_entry *rtt)
> +{
> +	struct arm_smccc_1_2_regs regs = {
> +		SMC_RMI_RTT_READ_ENTRY,
> +		rd, map_addr, level
> +	};
> +
> +	arm_smccc_1_2_smc(&regs, &regs);
> +
> +	rtt->walk_level = regs.a1;
> +	rtt->state = regs.a2 & 0xFF;
> +	rtt->desc = regs.a3;
> +	rtt->ripas = regs.a4 & 1;
> +
> +	return regs.a0;
> +}
> +
> +static inline int rmi_rtt_set_ripas(unsigned long rd, unsigned long rec,
> +				    unsigned long map_addr, unsigned long level,
> +				    unsigned long ripas)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_RTT_SET_RIPAS, rd, rec, map_addr, level,
> +			     ripas, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline int rmi_rtt_unmap_unprotected(unsigned long rd,
> +					    unsigned long map_addr,
> +					    unsigned long level)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_RTT_UNMAP_UNPROTECTED, rd, map_addr,
> +			     level, &res);
> +
> +	return res.a0;
> +}
> +
> +static inline phys_addr_t rmi_rtt_get_phys(struct rtt_entry *rtt)
> +{
> +	return rtt->desc & GENMASK(47, 12);
> +}
> +
> +#endif