Re: [PATCH v6 03/23] RISC-V: Add defines for the SBI message proxy extension

[Atish Patra <atish.patra@linux.dev>]

On 6/18/25 5:13 AM, Anup Patel wrote:
> Add defines for the new SBI message proxy extension which is part
> of the SBI v3.0 specification.
>
> Co-developed-by: Rahul Pathak <rpathak@ventanamicro.com>
> Signed-off-by: Rahul Pathak <rpathak@ventanamicro.com>
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> ---
>   arch/riscv/include/asm/sbi.h | 63 ++++++++++++++++++++++++++++++++++++
>   include/linux/wordpart.h     |  8 +++++
>   2 files changed, 71 insertions(+)
>
> diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
> index 341e74238aa0..59a7285ff956 100644
> --- a/arch/riscv/include/asm/sbi.h
> +++ b/arch/riscv/include/asm/sbi.h
> @@ -10,6 +10,7 @@
>   #include <linux/types.h>
>   #include <linux/cpumask.h>
>   #include <linux/jump_label.h>
> +#include <linux/wordpart.h>
>   
>   #ifdef CONFIG_RISCV_SBI
>   enum sbi_ext_id {
> @@ -36,6 +37,7 @@ enum sbi_ext_id {
>   	SBI_EXT_STA = 0x535441,
>   	SBI_EXT_NACL = 0x4E41434C,
>   	SBI_EXT_FWFT = 0x46574654,
> +	SBI_EXT_MPXY = 0x4D505859,
>   
>   	/* Experimentals extensions must lie within this range */
>   	SBI_EXT_EXPERIMENTAL_START = 0x08000000,
> @@ -430,6 +432,67 @@ enum sbi_fwft_feature_t {
>   
>   #define SBI_FWFT_SET_FLAG_LOCK			BIT(0)
>   
> +enum sbi_ext_mpxy_fid {
> +	SBI_EXT_MPXY_GET_SHMEM_SIZE,
> +	SBI_EXT_MPXY_SET_SHMEM,
> +	SBI_EXT_MPXY_GET_CHANNEL_IDS,
> +	SBI_EXT_MPXY_READ_ATTRS,
> +	SBI_EXT_MPXY_WRITE_ATTRS,
> +	SBI_EXT_MPXY_SEND_MSG_WITH_RESP,
> +	SBI_EXT_MPXY_SEND_MSG_WITHOUT_RESP,
> +	SBI_EXT_MPXY_GET_NOTIFICATION_EVENTS
> +};
> +
> +enum sbi_mpxy_attribute_id {
> +	/* Standard channel attributes managed by MPXY framework */
> +	SBI_MPXY_ATTR_MSG_PROT_ID		= 0x00000000,
> +	SBI_MPXY_ATTR_MSG_PROT_VER		= 0x00000001,
> +	SBI_MPXY_ATTR_MSG_MAX_LEN		= 0x00000002,
> +	SBI_MPXY_ATTR_MSG_SEND_TIMEOUT		= 0x00000003,
> +	SBI_MPXY_ATTR_MSG_COMPLETION_TIMEOUT	= 0x00000004,
> +	SBI_MPXY_ATTR_CHANNEL_CAPABILITY	= 0x00000005,
> +	SBI_MPXY_ATTR_SSE_EVENT_ID		= 0x00000006,
> +	SBI_MPXY_ATTR_MSI_CONTROL		= 0x00000007,
> +	SBI_MPXY_ATTR_MSI_ADDR_LO		= 0x00000008,
> +	SBI_MPXY_ATTR_MSI_ADDR_HI		= 0x00000009,
> +	SBI_MPXY_ATTR_MSI_DATA			= 0x0000000A,
> +	SBI_MPXY_ATTR_EVENTS_STATE_CONTROL	= 0x0000000B,
> +	SBI_MPXY_ATTR_STD_ATTR_MAX_IDX,
> +	/*
> +	 * Message protocol specific attributes, managed by
> +	 * the message protocol specification.
> +	 */
> +	SBI_MPXY_ATTR_MSGPROTO_ATTR_START	= 0x80000000,
> +	SBI_MPXY_ATTR_MSGPROTO_ATTR_END		= 0xffffffff
> +};
> +
> +/* Possible values of MSG_PROT_ID attribute */
> +enum sbi_mpxy_msgproto_id {
> +	SBI_MPXY_MSGPROTO_RPMI_ID = 0x0
> +};
> +
> +/* RPMI message protocol specific MPXY attributes */
> +enum sbi_mpxy_rpmi_attribute_id {
> +	SBI_MPXY_RPMI_ATTR_SERVICEGROUP_ID = SBI_MPXY_ATTR_MSGPROTO_ATTR_START,
> +	SBReviewed-by: Atish Patra <atishp@rivosinc.com>I_MPXY_RPMI_ATTR_SERVICEGROUP_VERSION,
> +	SBI_MPXY_RPMI_ATTR_IMPL_ID,
> +	SBI_MPXY_RPMI_ATTR_IMPL_VERSION,
> +	SBI_MPXY_RPMI_ATTR_MAX_ID
> +};
> +
> +/* Encoding of MSG_PROT_VER attribute */
> +#define SBI_MPXY_MSG_PROT_VER_MAJOR(__ver)	upper_16_bits(__ver)
> +#define SBI_MPXY_MSG_PROT_VER_MINOR(__ver)	lower_16_bits(__ver)
> +#define SBI_MPXY_MSG_PROT_MKVER(__maj, __min)	make_u32_from_two_u16(__maj, __min)
> +
> +/* Capabilities available through CHANNEL_CAPABILITY attribute */
> +#define SBI_MPXY_CHAN_CAP_MSI			BIT(0)
> +#define SBI_MPXY_CHAN_CAP_SSE			BIT(1)
> +#define SBI_MPXY_CHAN_CAP_EVENTS_STATE		BIT(2)
> +#define SBI_MPXY_CHAN_CAP_SEND_WITH_RESP	BIT(3)
> +#define SBI_MPXY_CHAN_CAP_SEND_WITHOUT_RESP	BIT(4)
> +#define SBI_MPXY_CHAN_CAP_GET_NOTIFICATIONS	BIT(5)
> +
>   /* SBI spec version fields */
>   #define SBI_SPEC_VERSION_DEFAULT	0x1
>   #define SBI_SPEC_VERSION_MAJOR_SHIFT	24
> diff --git a/include/linux/wordpart.h b/include/linux/wordpart.h
> index 5a7b97bb7c95..ed8717730037 100644
> --- a/include/linux/wordpart.h
> +++ b/include/linux/wordpart.h
> @@ -31,6 +31,14 @@
>    */
>   #define lower_16_bits(n) ((u16)((n) & 0xffff))
>   
> +/**
> + * make_u32_from_two_u16 - return u32 number by combining
> + * two u16 numbers.
> + * @hi: upper 16 bit number
> + * @lo: lower 16 bit number
> + */
> +#define make_u32_from_two_u16(hi, lo)	(((u32)(hi) << 16) | (u32)(lo))
> +
>   /**
>    * REPEAT_BYTE - repeat the value @x multiple times as an unsigned long value
>    * @x: value to repeat
LGTM.
Reviewed-by: Atish Patra <atishp@rivosinc.com>