[PATCH v17 1/7] firmware: arm_rmm: Add SMC definitions for calling the RMM
Gavin Shan
gshan at redhat.com
Tue Sep 8 15:41:23 PDT 2026
On 9/8/26 8:37 PM, Suzuki K Poulose wrote:
> On 08/09/2026 07:19, Gavin Shan wrote:
>> On 9/7/26 7:59 PM, Suzuki K Poulose wrote:
>>> From: Steven Price <steven.price at arm.com>
>>>
>>> The RMM (Realm Management Monitor) provides functionality that can be
>>> accessed by SMC calls from the host.
>>>
>>> The SMC definitions are based on DEN0137[1] version 2.0-bet3
>>>
>>> [1] https://developer.arm.com/documentation/den0137/2-0bet3/
>>>
>>> Signed-off-by: Steven Price <steven.price at arm.com>
>>> Signed-off-by: Suzuki K Poulose <suzuki.poulose at arm.com>
>
> ...
>
>>> ---
>>> include/linux/arm-smccc-rmi.h | 494 ++++++++++++++++++++++++++++++++++
>>> 1 file changed, 494 insertions(+)
>>> create mode 100644 include/linux/arm-smccc-rmi.h
>>>
>>
>> Some nitpicks below, please pick up the commits that look reasonable :)
>>
>
>
>>> +
>>> +#define RMI_RETURN_STATUS_MASK (0xFFUL)
>>> +#define RMI_RETURN_INDEX_MASK (0xFFUL << 8)
>>> +#define RMI_RETURN_MEMREQ_MASK (0x3UL << 8)
>>> +#define RMI_RETURN_CAN_CANCEL_MASK (0x1UL << 10)
>>> +
>>> +#define RMI_RETURN_STATUS(ret) FIELD_GET(RMI_RETURN_STATUS_MASK, ret)
>>> +#define RMI_RETURN_INDEX(ret) FIELD_GET(RMI_RETURN_INDEX_MASK, ret)
>>> +#define RMI_RETURN_MEMREQ(ret) FIELD_GET(RMI_RETURN_MEMREQ_MASK, ret)
>>> +#define RMI_RETURN_CAN_CANCEL(ret) FIELD_GET(RMI_RETURN_CAN_CANCEL_MASK, ret)
>>> +
>>
>> If I'm correct enough, RMI_RETURN_{STATUS, INDEX, MEMREQ, CAN_CANEL} _MASK are used
>> for once in this header file. So we needn't explicitly expose them and combine their
>> definitions with users to fetch the corresponding fields, as below.
>>
>> #define RMI_RETURN_STATUS(ret) FIELD_GET(GENMASK(7, 0), ret)
>> #define RMI_RETURN_INDEX(ret) FIELD_GET(GENMASK(15, 8), ret)
>> #define RMI_RETURN_MEMREQ(ret) FIELD_GET(GENMASK(10, 8), ret)
>> #define RMI_RETURN_CAN_CANCEL(ret) FIELD_GEt(GENMASK(10, 10), ret)
>
> I belive the header files were generated from a tool (by Steven) and
> these would make it easier to compare with the generated header file for
> any deviation from the spec. So, I am a bit reluctant make these
> changes.
>
> That said, I am happy to convert the mask definitions to GENMASK() for
> consistency and readability. i.e., something like:
>
> diff --git a/include/linux/arm-smccc-rmi.h b/include/linux/arm-smccc-rmi.h
> index 3eb88caf40964..078197284415e 100644
> --- a/include/linux/arm-smccc-rmi.h
> +++ b/include/linux/arm-smccc-rmi.h
> @@ -139,10 +139,10 @@
> #define RMI_ABI_VERSION_GET_MINOR(version) ((version) & 0xFFFF)
> #define RMI_ABI_VERSION(major, minor) (((major) << 16) | (minor))
>
> -#define RMI_RETURN_STATUS_MASK (0xFFUL)
> -#define RMI_RETURN_INDEX_MASK (0xFFUL << 8)
> -#define RMI_RETURN_MEMREQ_MASK (0x3UL << 8)
> -#define RMI_RETURN_CAN_CANCEL_MASK (0x1UL << 10)
> +#define RMI_RETURN_STATUS_MASK GENMASK(7, 0)
> +#define RMI_RETURN_INDEX_MASK GENMASK(15, 8)
> +#define RMI_RETURN_MEMREQ_MASK GENMASK(10, 8)
> +#define RMI_RETURN_CAN_CANCEL_MASK BIT(10)
>
Ok.
>>
>>> +#define RMI_SUCCESS 0
>>> +#define RMI_ERROR_INPUT 1
>>> +#define RMI_ERROR_REALM 2
>>> +#define RMI_ERROR_REC 3
>>> +#define RMI_ERROR_RTT 4
>>> +#define RMI_ERROR_NOT_SUPPORTED 5
>>> +#define RMI_ERROR_DEVICE 6
>>> +#define RMI_ERROR_RTT_AUX 7
>>> +#define RMI_ERROR_PSMMU_ST 8
>>> +#define RMI_ERROR_DPT 9
>>> +#define RMI_BUSY 10
>>> +#define RMI_ERROR_GLOBAL 11
>>> +#define RMI_ERROR_TRACKING 12
>>> +#define RMI_INCOMPLETE 13
>>> +#define RMI_BLOCKED 14
>>> +#define RMI_ERROR_GPT 15
>>> +#define RMI_ERROR_GRANULE 16
>>> +
>>> +#define RMI_CONTINUE_KEEP_GOING 0
>>> +#define RMI_CONTINUE_STOP 1
>>> +
>>> +#define RMI_OP_MEM_REQ_NONE 0
>>> +#define RMI_OP_MEM_REQ_DONATE 1
>>> +#define RMI_OP_MEM_REQ_RECLAIM 2
>>> +
>>> +#define RMI_DONATE_SIZE_MASK 3UL
>>> +#define RMI_DONATE_COUNT_MASK GENMASK(15, 2)
>>> +#define RMI_DONATE_CONTIG_MASK BIT(16)
>>> +#define RMI_DONATE_STATE_MASK GENMASK(18, 17)
>>> +
>>> +#define RMI_DONATE_SIZE(req) FIELD_GET(RMI_DONATE_SIZE_MASK, req)
>>> +#define RMI_DONATE_COUNT(req) FIELD_GET(RMI_DONATE_COUNT_MASK, req)
>>> +#define RMI_DONATE_CONTIG(req) FIELD_GET(RMI_DONATE_CONTIG_MASK, req)
>>> +#define RMI_DONATE_STATE(req) FIELD_GET(RMI_DONATE_STATE_MASK, req)
>>> +
>>
>> As above, RMI_DONATE_{SIZE, COUNT, CONTIG, STATE}_MASK are used for once in this
>> header file. So their definitions can be dropped by modifying the followup macros,
>> as below. Some enhancements are also applicable: (a) Use 'BLOCK' to indicate the
>> unit encoded in the request. (b) The macros are put into order from MSB to LSB.
>>
>> #define RMI_DONATE_STATE(req) FIELD_GET(GENMASK(18, 17), req)
>> #define RMI_DONATE_CONTIG(req) FIELD_GET(GENMASK(16, 16), req)
>> #define RMI_DONATE_BLOCK_COUNT(req) FIELD_GET(GENMASK(15, 2), req)
>> #define RMI_DONATE_BLOCK_SIZE(req) FIELD_GET(GENMASK(1, 0), req)
>
> Same as above.
>
Please rename RMI_DONATE_{SIZE, COUNT} to RMI_DONATE_BLOCK_{SIZE, COUNT} if possible.
>>
>>> +#define RMI_OP_MEM_DELEGATED 0
>>> +#define RMI_OP_MEM_UNDELEGATED 1
>>> +#define RMI_OP_MEM_CONDITIONAL 2
>>> +
>>
>> B4.6.40 RmiOpMemContig type is missed here and they should be used in the c code.
>>
>> #define RMI_OP_MEM_NON_CONTIG 0
>> #define RMI_OP_MEM_CONTIG 1
>>
>> In the c code, we shall have:
>>
>> if (RMI_DONATE_CONTIG(req) == RMI_OP_MEM_CONTIG)) {
>> ...
>> } else {
>> ...
>> }
>>
>
> Does it make much sense though ? I prefer
>
> if (RMI_DONATE_CONTIG(req))
>
> to
>
>
> if (RMI_DONATE_CONTIG(req) == RMI_OP_MEM_CONTIG)) {
>
>
> than having a field for a single bit values. I am happy to change
> this if there is strong preference to the other.
>
The point is RMM-v2.0-bet3 expose RMI_OP_{MEM, MEM_NON}_CONTIG instead of true/false
to indicate if the requested memory blocks are physically contiguous or not. So the
expression 'if (RMI_DONATE_CONTIG(req) == RMI_OP_MEM_CONTIG)' is consistent to the
RMM-v2.0-bet3 spec.
>> Similarly, B4.6.39 RmiOpCanCancel type is missed here and they should be used in
>> the c code.
>>
>> #define RMI_OP_CANNOT_CANCEL 0
>> #define RMI_OP_CAN_CANCEL 1
>>
>> In the c code, we shall have:
>>
>> if (RMI_RETURN_CAN_CANCEL(ret) == RMI_OP_CAN_CANCEL) {
>> ...
>> } else {
>> ...
>> }
>>
>
> Same as above.
>
Please see above explanation.
>>> +#define RMI_ADDR_TYPE_NONE 0
>>> +#define RMI_ADDR_TYPE_SINGLE 1
>>> +#define RMI_ADDR_TYPE_LIST 2
>>> +
>>> +#define RMI_ADDR_RANGE_SIZE_MASK GENMASK(1, 0)
>>> +#define RMI_ADDR_RANGE_COUNT_MASK GENMASK(PAGE_SHIFT - 1, 2)
>>> +#define RMI_ADDR_RANGE_ADDR_MASK (PAGE_MASK & GENMASK(51, 0))
>>> +#define RMI_ADDR_RANGE_STATE_MASK GENMASK(63, 62)
>>> +
>>> +#define RMI_ADDR_RANGE_SIZE(ar) (FIELD_GET(RMI_ADDR_RANGE_SIZE_MASK, \
>>> + (ar)))
>>> +#define RMI_ADDR_RANGE_COUNT(ar) (FIELD_GET(RMI_ADDR_RANGE_COUNT_MASK, \
>>> + (ar)))
>>> +#define RMI_ADDR_RANGE_ADDR(ar) ((ar) & RMI_ADDR_RANGE_ADDR_MASK)
>>> +#define RMI_ADDR_RANGE_STATE(ar) (FIELD_GET(RMI_ADDR_RANGE_STATE_MASK, \
>>> + (ar)))
>>> +
>>
>> I guess it wouldn't a bad idea to explictly indicate 'BLOCK' in the definitions, as
>> below. Some improvements are applicated either: (a) 'ar' is renamed to 'r'; (b) The
>> excessive parentheses are dropped to follow the patterns we already had; (c) For
>> RMI_ADDR_RANGE_ADDR(r), FIELD_GET() is used.
>>
>> #define RMI_ADDR_RANGE_BLOCK_SIZE_MASK GENMASK(1, 0)
>> #define RMI_ADDR_RANGE_BLOCK_COUNT_MASK GENMASK(PAGE_SHIFT - 1, 2)
>> #define RMI_ADDR_RANGE_ADDR_MASK (PAGE_MASK & GENMASK(51, 0))
>> #define RMI_ADDR_RANGE_STATE_MASK GENMASK(63, 62)
>>
>> #define RMI_ADDR_RANGE_BLOCK_SIZE(r) FIELD_GET(RMI_ADDR_RANGE_SIZE_MASK, r)
>> #define RMI_ADDR_RANGE_BLOCK_COUNT(r) FIELD_GET(RMI_ADDR_RANGE_COUNT_MASK, r)
>> #define RMI_ADDR_RANGE_ADDR(r) FIELD_GET(RMI_ADDR_RANGE_ADDR_MASK, r)
>> #define RMI_ADDR_RANGE_STATE(r) FIELD_GET(RMI_ADDR_RANGE_STATE_MASK, r)
>
> Ack
>
>>
>>> +enum rmi_ripas {
>>> + RMI_EMPTY = 0,
>>> + RMI_RAM = 1,
>>> + RMI_DESTROYED = 2,
>>> + RMI_DEV = 3,
>>> +};
>
>>> +#define RMI_FEATURE_REGISTER_1_RMI_GRAN_SZ_4KB BIT(0)
>>> +#define RMI_FEATURE_REGISTER_1_RMI_GRAN_SZ_16KB BIT(1)
>>> +#define RMI_FEATURE_REGISTER_1_RMI_GRAN_SZ_64KB BIT(2)
>>> +#define RMI_FEATURE_REGISTER_1_HASH_SHA_256 BIT(3)
>>> +#define RMI_FEATURE_REGISTER_1_HASH_SHA_384 BIT(4)
>>> +#define RMI_FEATURE_REGISTER_1_HASH_SHA_512 BIT(5)
>>> +#define RMI_FEATURE_REGISTER_1_MAX_RECS_ORDER GENMASK(9, 6)
>>> +#define RMI_FEATURE_REGISTER_1_L0GPTSZ GENMASK(13, 10)
>>> +#define RMI_FEATURE_REGISTER_1_PPS GENMASK(16, 14)
>>> +
>>> +#define RMI_FEATURE_REGISTER_2_DA BIT(0)
>>> +#define RMI_FEATURE_REGISTER_2_DA_COH BIT(1)
>>> +#define RMI_FEATURE_REGISTER_2_VSMMU BIT(2)
>>> +#define RMI_FEATURE_REGISTER_2_ATS BIT(3)
>>> +#define RMI_FEATURE_REGISTER_2_PDEV_MAX_VDEVS_ORDER GENMASK(7, 4)
>>> +#define RMI_FEATURE_REGISTER_2_VDEV_KROU BIT(8)
>>> +#define RMI_FEATURE_REGISTER_2_NON_TEE_STREAM BIT(9)
>>> +#define RMI_FEATURE_REGISTER_2_REALM_MAX_VDEVS_ORDER GENMASK(14, 10)
>>> +
>>> +#define RMI_FEATURE_REGISTER_3_MAX_NUM_AUX_PLANES GENMASK(3, 0)
>>> +#define RMI_FEATURE_REGISTER_3_RTT_PLANE GENMASK(5, 4)
>>> +#define RMI_FEATURE_REGISTER_3_RTT_S2AP_INDIRECT BIT(6)
>>> +
>>> +#define RMI_FEATURE_REGISTER_4_MEC_COUNT GENMASK(63, 0)
>>> +
>>
>> We would reorder those feature register definitions from MSB ro LSB :-)
>
> Ack
>
> Thanks for your review.
>
> Cheers
> Suzuki
>
Thanks,
Gavin
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