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.

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 MPAMF_IDR.HAS_MBW_PART == 1 and MPAMF_MBW_IDR.HAS_PROP == 1. Otherwise, direct accesses to MPAMCFG_MBW_PROP are RES0.

Attributes

MPAMCFG_MBW_PROP is a 32-bit register.

Field descriptions

The MPAMCFG_MBW_PROP bit assignments are:

EN, bit [31]

Enable proportional stride bandwidth partitioning.

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 the MPAMCFG_MBW_PROP

This register is within the MPAM feature page memory frames. In a system that supports Secure and Non-secure memory maps, there must be both Secure and Non-secure MPAM feature pages.

MPAMCFG_MBW_PROP_s must be accessible from the Secure MPAM feature page. MPAMCFG_MBW_PROP_ns must be accessible from the Non-secure MPAM feature page.

MPAMCFG_MBW_PROP_s and MPAMCFG_MBW_PROP_ns must be separate registers. The Secure instance (MPAMCFG_MBW_PROP_s) accesses the memory proportional stride bandwidth partitioning used for Secure PARTIDs, and the Non-secure instance (MPAMCFG_MBW_PROP_ns) accesses the memory proportional stride bandwidth partitioning used for Non-secure 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:

Accesses on this interface are RW.

Accesses on this interface are RW.