diff mbox series

[v2,06/43] arm64: RME: Add wrappers for RMI calls

Message ID 20240412084309.1733783-7-steven.price@arm.com (mailing list archive)
State New, archived
Headers show
Series arm64: Support for Arm CCA in KVM | expand

Commit Message

Steven Price April 12, 2024, 8:42 a.m. UTC
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 | 509 ++++++++++++++++++++++++++++++
 1 file changed, 509 insertions(+)
 create mode 100644 arch/arm64/include/asm/rmi_cmds.h

Comments

Suzuki K Poulose April 16, 2024, 1:14 p.m. UTC | #1
Hi Steven

On 12/04/2024 09:42, 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.
> 

I have compared the parameters and output values to that of the RMM spec
and they match. There are some minor nits below.

> Signed-off-by: Steven Price <steven.price@arm.com>
> ---
>   arch/arm64/include/asm/rmi_cmds.h | 509 ++++++++++++++++++++++++++++++
>   1 file changed, 509 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..c21414127e8e
> --- /dev/null
> +++ b/arch/arm64/include/asm/rmi_cmds.h
> @@ -0,0 +1,509 @@
> +/* 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;
> +	int ripas;
> +};
> +

...

> +/**
> + * rmi_data_destroy() - Destroy a Data Granule
> + * @rd: PA of the RD
> + * @ipa: IPA at which the granule is mapped in the guest
> + * @data_out: PA of the granule which was destroyed
> + * @top_out: Top IPA of non-live RTT entries
> + *
> + * Transitions the granule to DESTROYED state, the address cannot be used by
> + * the guest for the lifetime of the Realm.
> + *
> + * Return: RMI return code
> + */
> +static inline int rmi_data_destroy(unsigned long rd, unsigned long ipa,
> +				   unsigned long *data_out,
> +				   unsigned long *top_out)
> +{
> +	struct arm_smccc_res res;
> +
> +	arm_smccc_1_1_invoke(SMC_RMI_DATA_DESTROY, rd, ipa, &res);
> +
> +	*data_out = res.a1;
> +	*top_out = res.a2;

minor nit: Do we need to be safer by checking the parameters before 
filling them in ? i.e.,

	if (ptr)
		*ptr = result_out;

This applies for others calls below.

> +
> +	return res.a0;
> +}

> +
> +/**
> + * rmi_realm_destroy() - Destroy a Realm
> + * @rd: PA of the RD
> + *
> + * Destroys a Realm, all objects belonging to the Realm must be destroyed first.
> + *
> + * Return: RMI return code
> + */
> +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;
> +}
> +
> +/**
> + * rmi_rec_aux_count() - Get number of auxiliary Granules required
> + * @rd: PA of the RD
> + * @aux_count: Number of pages written to this pointer
> + *
> + * A REC may require extra auxiliary pages to be delegateed for the RMM to

minor nit: "s/delegateed/delegated/"

...

> +/**
> + * rmi_rtt_read_entry() - Read an RTTE
> + * @rd: PA of the RD
> + * @ipa: IPA for which to read the RTTE
> + * @level: RTT level at which to read the RTTE
> + * @rtt: Output structure describing the RTTE
> + *
> + * Reads a RTTE (Realm Translation Table Entry).
> + *
> + * Return: RMI return code
> + */
> +static inline int rmi_rtt_read_entry(unsigned long rd, unsigned long ipa,
> +				     long level, struct rtt_entry *rtt)
> +{
> +	struct arm_smccc_1_2_regs regs = {
> +		SMC_RMI_RTT_READ_ENTRY,
> +		rd, ipa, level
> +	};
> +
> +	arm_smccc_1_2_smc(&regs, &regs);
> +
> +	rtt->walk_level = regs.a1;
> +	rtt->state = regs.a2 & 0xFF;

minor nit: We mask the state, but not the "ripas". Both of them are u8. 
For consistency, we should mask both or neither.

> +	rtt->desc = regs.a3;
> +	rtt->ripas = regs.a4;
> +
> +	return regs.a0;
> +}
> +

...

> +/**
> + * rmi_rtt_get_phys() - Get the PA from a RTTE
> + * @rtt: The RTTE
> + *
> + * Return: the physical address from a RTT entry.
> + */
> +static inline phys_addr_t rmi_rtt_get_phys(struct rtt_entry *rtt)
> +{
> +	return rtt->desc & GENMASK(47, 12);
> +}

I guess this may need to change with the LPA2 support in RMM and must be
used in conjunction with the "realm" object to make the correct
conversion.


Suzuki


> +
> +#endif
Steven Price April 19, 2024, 11:18 a.m. UTC | #2
On 16/04/2024 14:14, Suzuki K Poulose wrote:
> Hi Steven
> 
> On 12/04/2024 09:42, 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.
>>
> 
> I have compared the parameters and output values to that of the RMM spec
> and they match. There are some minor nits below.
> 
>> Signed-off-by: Steven Price <steven.price@arm.com>
>> ---
>>   arch/arm64/include/asm/rmi_cmds.h | 509 ++++++++++++++++++++++++++++++
>>   1 file changed, 509 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..c21414127e8e
>> --- /dev/null
>> +++ b/arch/arm64/include/asm/rmi_cmds.h
>> @@ -0,0 +1,509 @@
>> +/* 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;
>> +    int ripas;
>> +};
>> +
> 
> ...
> 
>> +/**
>> + * rmi_data_destroy() - Destroy a Data Granule
>> + * @rd: PA of the RD
>> + * @ipa: IPA at which the granule is mapped in the guest
>> + * @data_out: PA of the granule which was destroyed
>> + * @top_out: Top IPA of non-live RTT entries
>> + *
>> + * Transitions the granule to DESTROYED state, the address cannot be
>> used by
>> + * the guest for the lifetime of the Realm.
>> + *
>> + * Return: RMI return code
>> + */
>> +static inline int rmi_data_destroy(unsigned long rd, unsigned long ipa,
>> +                   unsigned long *data_out,
>> +                   unsigned long *top_out)
>> +{
>> +    struct arm_smccc_res res;
>> +
>> +    arm_smccc_1_1_invoke(SMC_RMI_DATA_DESTROY, rd, ipa, &res);
>> +
>> +    *data_out = res.a1;
>> +    *top_out = res.a2;
> 
> minor nit: Do we need to be safer by checking the parameters before
> filling them in ? i.e.,
> 
>     if (ptr)
>         *ptr = result_out;
> 
> This applies for others calls below.

I had taken the approach of making all the out-parameters required (i.e.
non-NULL). But I guess I can switch over to allowing NULL - hopefully
the compiler will optimise these checks away, but there are some
situations where we are currently ignoring the extra out-parameters that
could be tidied up.

> 
>> +
>> +    return res.a0;
>> +}
> 
>> +
>> +/**
>> + * rmi_realm_destroy() - Destroy a Realm
>> + * @rd: PA of the RD
>> + *
>> + * Destroys a Realm, all objects belonging to the Realm must be
>> destroyed first.
>> + *
>> + * Return: RMI return code
>> + */
>> +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;
>> +}
>> +
>> +/**
>> + * rmi_rec_aux_count() - Get number of auxiliary Granules required
>> + * @rd: PA of the RD
>> + * @aux_count: Number of pages written to this pointer
>> + *
>> + * A REC may require extra auxiliary pages to be delegateed for the
>> RMM to
> 
> minor nit: "s/delegateed/delegated/"
> 
> ...
> 
>> +/**
>> + * rmi_rtt_read_entry() - Read an RTTE
>> + * @rd: PA of the RD
>> + * @ipa: IPA for which to read the RTTE
>> + * @level: RTT level at which to read the RTTE
>> + * @rtt: Output structure describing the RTTE
>> + *
>> + * Reads a RTTE (Realm Translation Table Entry).
>> + *
>> + * Return: RMI return code
>> + */
>> +static inline int rmi_rtt_read_entry(unsigned long rd, unsigned long
>> ipa,
>> +                     long level, struct rtt_entry *rtt)
>> +{
>> +    struct arm_smccc_1_2_regs regs = {
>> +        SMC_RMI_RTT_READ_ENTRY,
>> +        rd, ipa, level
>> +    };
>> +
>> +    arm_smccc_1_2_smc(&regs, &regs);
>> +
>> +    rtt->walk_level = regs.a1;
>> +    rtt->state = regs.a2 & 0xFF;
> 
> minor nit: We mask the state, but not the "ripas". Both of them are u8.
> For consistency, we should mask both or neither.

Good point - I'll mask ripas as well. I suspect this is a bug that crept
in when I was updating for the new RIPAS state.

>> +    rtt->desc = regs.a3;
>> +    rtt->ripas = regs.a4;
>> +
>> +    return regs.a0;
>> +}
>> +
> 
> ...
> 
>> +/**
>> + * rmi_rtt_get_phys() - Get the PA from a RTTE
>> + * @rtt: The RTTE
>> + *
>> + * Return: the physical address from a RTT entry.
>> + */
>> +static inline phys_addr_t rmi_rtt_get_phys(struct rtt_entry *rtt)
>> +{
>> +    return rtt->desc & GENMASK(47, 12);
>> +}
> 
> I guess this may need to change with the LPA2 support in RMM and must be
> used in conjunction with the "realm" object to make the correct
> conversion.

Actually this is currently unused, and there's a potential bug lurking
in realm_map_protected() where rtt->desc is assumed to be a valid
physical address. I'll move the function there and fix it up by also
taking a realm argument. I've tried to keep the realm structure out of
this file.

Thanks,

Steve
diff mbox series

Patch

diff --git a/arch/arm64/include/asm/rmi_cmds.h b/arch/arm64/include/asm/rmi_cmds.h
new file mode 100644
index 000000000000..c21414127e8e
--- /dev/null
+++ b/arch/arm64/include/asm/rmi_cmds.h
@@ -0,0 +1,509 @@ 
+/* 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;
+	int ripas;
+};
+
+/**
+ * rmi_data_create() - Create a Data Granule
+ * @rd: PA of the RD
+ * @data: PA of the target granule
+ * @ipa: IPA at which the granule will be mapped in the guest
+ * @src: PA of the source granule
+ * @flags: RMI_MEASURE_CONTENT if the contents should be measured
+ *
+ * Create a new Data Granule, copying contents from a Non-secure Granule.
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_data_create(unsigned long rd, unsigned long data,
+				  unsigned long ipa, unsigned long src,
+				  unsigned long flags)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_DATA_CREATE, rd, data, ipa, src,
+			     flags, &res);
+
+	return res.a0;
+}
+
+/**
+ * rmi_data_create_unknown() - Create a Data Granule with unknown contents
+ * @rd: PA of the RD
+ * @data: PA of the target granule
+ * @ipa: IPA at which the granule will be mapped in the guest
+ *
+ * Create a new Data Granule with unknown contents
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_data_create_unknown(unsigned long rd,
+					  unsigned long data,
+					  unsigned long ipa)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_DATA_CREATE_UNKNOWN, rd, data, ipa, &res);
+
+	return res.a0;
+}
+
+/**
+ * rmi_data_destroy() - Destroy a Data Granule
+ * @rd: PA of the RD
+ * @ipa: IPA at which the granule is mapped in the guest
+ * @data_out: PA of the granule which was destroyed
+ * @top_out: Top IPA of non-live RTT entries
+ *
+ * Transitions the granule to DESTROYED state, the address cannot be used by
+ * the guest for the lifetime of the Realm.
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_data_destroy(unsigned long rd, unsigned long ipa,
+				   unsigned long *data_out,
+				   unsigned long *top_out)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_DATA_DESTROY, rd, ipa, &res);
+
+	*data_out = res.a1;
+	*top_out = res.a2;
+
+	return res.a0;
+}
+
+/**
+ * rmi_features() - Read feature register
+ * @index: Feature register index
+ * @out: Feature register value is written to this pointer
+ *
+ * Return: RMI return code
+ */
+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;
+}
+
+/**
+ * rmi_granule_delegate() - Delegate a Granule
+ * @phys: PA of the Granule
+ *
+ * Delegate a Granule for use by the Realm World.
+ *
+ * Return: RMI return code
+ */
+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;
+}
+
+/**
+ * rmi_granule_undelegate() - Undelegate a Granule
+ * @phys: PA of the Granule
+ *
+ * Undelegate a Granule to allow use by the Normal World. Will fail if the
+ * Granule is in use.
+ *
+ * Return: RMI return code
+ */
+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;
+}
+
+/**
+ * rmi_psci_complete() - Complete pending PSCI command
+ * @calling_rec: PA of the calling REC
+ * @target_rec: PA of the target REC
+ * @status: Status of the PSCI request
+ *
+ * Completes a pending PSCI command which was called with an MPIDR argument, by
+ * providing the corresponding REC.
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_psci_complete(unsigned long calling_rec,
+				    unsigned long target_rec,
+				    unsigned long status)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_PSCI_COMPLETE, calling_rec, target_rec,
+			     status, &res);
+
+	return res.a0;
+}
+
+/**
+ * rmi_realm_activate() - Active a Realm
+ * @rd: PA of the RD
+ *
+ * Mark a Realm as Active signalling that creation is complete and allowing
+ * execution of the Realm.
+ *
+ * Return: RMI return code
+ */
+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;
+}
+
+/**
+ * rmi_realm_create() - Create a Realm
+ * @rd: PA of the RD
+ * @params_ptr: PA of Realm parameters
+ *
+ * Create a new Realm using the given parameters.
+ *
+ * Return: RMI return code
+ */
+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;
+}
+
+/**
+ * rmi_realm_destroy() - Destroy a Realm
+ * @rd: PA of the RD
+ *
+ * Destroys a Realm, all objects belonging to the Realm must be destroyed first.
+ *
+ * Return: RMI return code
+ */
+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;
+}
+
+/**
+ * rmi_rec_aux_count() - Get number of auxiliary Granules required
+ * @rd: PA of the RD
+ * @aux_count: Number of pages written to this pointer
+ *
+ * A REC may require extra auxiliary pages to be delegateed for the RMM to
+ * store metadata (not visible to the normal world) in. This function provides
+ * the number of pages that are required.
+ *
+ * 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);
+
+	*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;
+}
+
+/**
+ * rmi_rec_destroy() - Destroy a REC
+ * @rec: PA of the target REC
+ *
+ * Destroys a REC. The REC must not be running.
+ *
+ * Return: RMI return code
+ */
+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;
+}
+
+/**
+ * rmi_rec_enter() - Enter a REC
+ * @rec: PA of the target REC
+ * @run_ptr: PA of RecRun structure
+ *
+ * Starts (or continues) execution within a REC.
+ *
+ * Return: RMI return code
+ */
+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;
+}
+
+/**
+ * rmi_rtt_create() - Creates an RTT
+ * @rd: PA of the RD
+ * @rtt: PA of the target RTT
+ * @ipa: Base of the IPA range described by the RTT
+ * @level: Depth of the RTT within the tree
+ *
+ * Creates an RTT (Realm Translation Table) at the specified address and level
+ * within the realm.
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_rtt_create(unsigned long rd, unsigned long rtt,
+				 unsigned long ipa, long level)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_RTT_CREATE, rd, rtt, ipa, level, &res);
+
+	return res.a0;
+}
+
+/**
+ * rmi_rtt_destroy() - Destroy an RTT
+ * @rd: PA of the RD
+ * @ipa: Base of the IPA range described by the RTT
+ * @level: Depth of the RTT within the tree
+ * @out_rtt: Pointer to write the PA of the RTT which was destroyed
+ * @out_top: Pointer to write the top IPA of non-live RTT entries
+ *
+ * Destroys an RTT. The RTT must be empty.
+ *
+ * Return: RMI return code.
+ */
+static inline int rmi_rtt_destroy(unsigned long rd,
+				  unsigned long ipa,
+				  long level,
+				  unsigned long *out_rtt,
+				  unsigned long *out_top)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_RTT_DESTROY, rd, ipa, level, &res);
+
+	*out_rtt = res.a1;
+	*out_top = res.a2;
+
+	return res.a0;
+}
+
+/**
+ * rmi_rtt_fold() - Fold an RTT
+ * @rd: PA of the RD
+ * @ipa: Base of the IPA range described by the RTT
+ * @level: Depth of the RTT within the tree
+ * @out_rtt: Pointer to write the PA of the RTT which was destroyed
+ *
+ * Folds an RTT. If all entries with the RTT are 'homogeneous' the RTT can be
+ * folded into the parent and the RTT destroyed.
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_rtt_fold(unsigned long rd, unsigned long ipa,
+			       long level, unsigned long *out_rtt)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_RTT_FOLD, rd, ipa, level, &res);
+
+	*out_rtt = res.a1;
+
+	return res.a0;
+}
+
+/**
+ * rmi_rtt_init_ripas() - Set RIPAS for new Realm
+ * @rd: PA of the RD
+ * @base: Base of target IPA region
+ * @top: Top of target IPA region
+ * @out_top: Top IPA of range whose RIPAS was modified
+ *
+ * Sets the RIPAS of a target IPA range to RAM, for a Realm in the NEW state.
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_rtt_init_ripas(unsigned long rd, unsigned long base,
+				     unsigned long top, unsigned long *out_top)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_RTT_INIT_RIPAS, rd, base, top, &res);
+
+	*out_top = res.a1;
+
+	return res.a0;
+}
+
+/**
+ * rmi_rtt_map_unprotected() - Map NS pages into a Realm
+ * @rd: PA of the RD
+ * @ipa: Base IPA of the mapping
+ * @level: Depth within the RTT tree
+ * @desc: RTTE descriptor
+ *
+ * Create a mapping from an Unprotected IPA to a Non-secure PA.
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_rtt_map_unprotected(unsigned long rd,
+					  unsigned long ipa,
+					  long level,
+					  unsigned long desc)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_RTT_MAP_UNPROTECTED, rd, ipa, level,
+			     desc, &res);
+
+	return res.a0;
+}
+
+/**
+ * rmi_rtt_read_entry() - Read an RTTE
+ * @rd: PA of the RD
+ * @ipa: IPA for which to read the RTTE
+ * @level: RTT level at which to read the RTTE
+ * @rtt: Output structure describing the RTTE
+ *
+ * Reads a RTTE (Realm Translation Table Entry).
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_rtt_read_entry(unsigned long rd, unsigned long ipa,
+				     long level, struct rtt_entry *rtt)
+{
+	struct arm_smccc_1_2_regs regs = {
+		SMC_RMI_RTT_READ_ENTRY,
+		rd, ipa, 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;
+
+	return regs.a0;
+}
+
+/**
+ * rmi_rtt_set_ripas() - Set RIPAS for an running realm
+ * @rd: PA of the RD
+ * @rec: PA of the REC making the request
+ * @base: Base of target IPA region
+ * @top: Top of target IPA region
+ * @out_top: Pointer to write top IPA of range whose RIPAS was modified
+ *
+ * Completes a request made by the Realm to change the RIPAS of a target IPA
+ * range.
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_rtt_set_ripas(unsigned long rd, unsigned long rec,
+				    unsigned long base, unsigned long top,
+				    unsigned long *out_top)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_RTT_SET_RIPAS, rd, rec, base, top, &res);
+
+	*out_top = res.a1;
+
+	return res.a0;
+}
+
+/**
+ * rmi_rtt_unmap_unprotected() - Remove a NS mapping
+ * @rd: PA of the RD
+ * @ipa: Base IPA of the mapping
+ * @level: Depth within the RTT tree
+ * @out_top: Pointer to write top IPA of non-live RTT entries
+ *
+ * Removes a mapping at an Unprotected IPA.
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_rtt_unmap_unprotected(unsigned long rd,
+					    unsigned long ipa,
+					    long level,
+					    unsigned long *out_top)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_RTT_UNMAP_UNPROTECTED, rd, ipa,
+			     level, &res);
+
+	*out_top = res.a1;
+
+	return res.a0;
+}
+
+/**
+ * rmi_rtt_get_phys() - Get the PA from a RTTE
+ * @rtt: The RTTE
+ *
+ * Return: the physical address from a RTT entry.
+ */
+static inline phys_addr_t rmi_rtt_get_phys(struct rtt_entry *rtt)
+{
+	return rtt->desc & GENMASK(47, 12);
+}
+
+#endif