MPAMCFG_MBW_PROP, MPAM Memory Bandwidth Proportional Stride Partition Configuration Register

The MPAMCFG_MBW_PROP characteristics are:

Purpose

Controls the proportional stride of memory bandwidth that the PARTID selected by MPAMCFG_PART_SEL uses.

MPAMCFG_MBW_PROP_s controls the bandwidth proportional stride for the Secure PARTID selected by the Secure instance of MPAMCFG_PART_SEL. MPAMCFG_MBW_PROP_ns controls the bandwidth proportional stride for the Non-secure PARTID selected by the Non-secure instance of MPAMCFG_PART_SEL. MPAMCFG_MBW_PROP_rt controls the bandwidth proportional stride for the Root PARTID selected by the Root instance of MPAMCFG_PART_SEL. MPAMCFG_MBW_PROP_rl controls the bandwidth proportional stride for the Realm PARTID selected by the Realm instance of MPAMCFG_PART_SEL.

Proportional stride is a relative cost of bandwidth requested by one PARTID in relation to the costs of the bandwidths requested by each other PARTID also competing to use the bandwidth.

If MPAMF_IDR.HAS_RIS is 1, the control settings accessed are those of the resource instance currently selected by MPAMCFG_PART_SEL.RIS and the PARTID selected by MPAMCFG_PART_SEL.PARTID_SEL.

Configuration

The power domain of MPAMCFG_MBW_PROP is IMPLEMENTATION DEFINED.

This register is present only when FEAT_MPAM is implemented, MPAMF_IDR.HAS_MBW_PART == 1 and MPAMF_MBW_IDR.HAS_PROP == 1. Otherwise, direct accesses to MPAMCFG_MBW_PROP are RES0.

The power and reset domain of each MSC component is specific to that component.

Attributes

MPAMCFG_MBW_PROP is a 32-bit register.

Field descriptions

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
EN	RES0															STRIDEM1

EN, bit [31]

Enable proportional stride bandwidth partitioning.

EN	Meaning
0b0	The selected partition is not regulated by proportional stride bandwidth partitioning.
0b1	The selected partition has bandwidth usage regulated by proportional stride bandwidth partitioning as controlled by STRIDEM1.

Bits [30:16]

Reserved, RES0.

STRIDEM1, bits [15:0]

Memory bandwidth stride minus 1 allocated to the partition selected by MPAMCFG_PART_SEL. STRIDEM1 represents the normalized cost of bandwidth consumption by the partition.

The proportional stride partitioning control parameter is an unsigned integer representing the normalized cost to a partition for consuming bandwidth. Larger values have a larger cost and correspond to a lesser allocation of bandwidth while smaller values indicate a lesser cost and therefore a higher allocation of bandwidth.

The implemented width of STRIDEM1 is given in MPAMF_MBW_IDR.BWA_WD.

Accessing MPAMCFG_MBW_PROP

This register is within the MPAM feature page memory frames.

In a system that supports Secure, Non-secure, Root, and Realm memory maps, there must be MPAM feature pages in all four address maps:

MPAMCFG_MBW_PROP_s must only be accessible from the Secure MPAM feature page.
MPAMCFG_MBW_PROP_ns must only be accessible from the Non-secure MPAM feature page.
MPAMCFG_MBW_PROP_rt must only be accessible from the Root MPAM feature page.
MPAMCFG_MBW_PROP_rl must only be accessible from the Realm MPAM feature page.

MPAMCFG_MBW_PROP_s, MPAMCFG_MBW_PROP_ns, MPAMCFG_MBW_PROP_rt, and MPAMCFG_MBW_PROP_rl must be separate registers:

The Secure instance (MPAMCFG_MBW_PROP_s) accesses the memory proportional stride bandwidth partitioning used for Secure PARTIDs.
The Non-secure instance (MPAMCFG_MBW_PROP_ns) accesses the memory proportional stride bandwidth partitioning used for Non-secure PARTIDs.
The Root instance (MPAMCFG_MBW_PROP_rt) accesses the memory proportional stride bandwidth partitioning used for Root PARTIDs.
The Realm instance (MPAMCFG_MBW_PROP_rl) accesses the memory proportional stride bandwidth partitioning used for Realm PARTIDs.

When RIS is implemented, loads and stores to MPAMCFG_MBW_PROP access the memory proportional stride bandwidth partitioning configuration settings for the bandwidth resource instance selected by MPAMCFG_PART_SEL.RIS and the PARTID selected by MPAMCFG_PART_SEL.PARTID_SEL.

When RIS is not implemented, loads and stores to MPAMCFG_MBW_PROP access the memory proportional stride bandwidth partitioning configuration settings for the PARTID selected by MPAMCFG_PART_SEL.PARTID_SEL.

When PARTID narrowing is implemented, loads and stores to MPAMCFG_MBW_PROP access the memory proportional stride bandwidth partitioning configuration settings for the internal PARTID selected by MPAMCFG_PART_SEL.PARTID_SEL, and MPAMCFG_PART_SEL.INTERNAL must be 1.

When PARTID narrowing is not implemented, loads and stores to MPAMCFG_MBW_PROP access the memory proportional stride bandwidth partitioning configuration settings for the request PARTID selected by MPAMCFG_PART_SEL.PARTID_SEL, and MPAMCFG_PART_SEL.INTERNAL must be 0.

MPAMCFG_MBW_PROP can be accessed through the memory-mapped interfaces:

Component	Frame	Offset	Instance
MPAM	MPAMF_BASE_s	0x0500	MPAMCFG_MBW_PROP_s

Accesses on this interface are RW.

Component	Frame	Offset	Instance
MPAM	MPAMF_BASE_ns	0x0500	MPAMCFG_MBW_PROP_ns

Accesses on this interface are RW.

Component	Frame	Offset	Instance
MPAM	MPAMF_BASE_rt	0x0500	MPAMCFG_MBW_PROP_rt

When FEAT_RME is implemented, accesses on this interface are RW.

Component	Frame	Offset	Instance
MPAM	MPAMF_BASE_rl	0x0500	MPAMCFG_MBW_PROP_rl

When FEAT_RME is implemented, accesses on this interface are RW.

26/03/2024 09:49; 67c0ae5282a7629ba0ea0ba7267b43cd4f7939f6