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GICR_CLRLPIR

GICR_CLRLPIR, Clear LPI Pending Register

The GICR_CLRLPIR characteristics are:

Purpose

Clears the pending state of the specified LPI.

Configuration

A copy of this register is provided for each Redistributor.

Attributes

GICR_CLRLPIR is a 64-bit register.

Field descriptions

When GICR_TYPER.DirectLPI == 1:

63	62	61	60	59	58	57	56	55	54	53	52	51	50	49	48	47	46	45	44	43	42	41	40	39	38	37	36	35	34	33	32
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
RES0
pINTID

Bits [63:32]

Reserved, RES0.

pINTID, bits [31:0]

The INTID of the physical LPI.

Note

The size of this field is IMPLEMENTATION DEFINED, and is specified by the GICD_TYPER.IDbits field. Unimplemented bits are RES0.

When GICR_TYPER.DirectLPI == 0:

63	62	61	60	59	58	57	56	55	54	53	52	51	50	49	48	47	46	45	44	43	42	41	40	39	38	37	36	35	34	33	32
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
IMPLEMENTATION DEFINED
IMPLEMENTATION DEFINED

IMPLEMENTATION DEFINED, bits [63:0]

IMPLEMENTATION DEFINED.

Accessing GICR_CLRLPIR

When written with a 32-bit write the data is zero-extended to 64 bits.

This register is mandatory in an implementation that supports LPIs and does not include an ITS. The functionality of this register is IMPLEMENTATION DEFINED in an implementation that does include an ITS.

Writes to this register have no effect if any of the following apply:

GICR_CTLR.EnableLPIs == 0.
The pINTID value specifies an unimplemented LPI.
The pINTID value specifies an LPI that is not pending.

GICR_CLRLPIR can be accessed through the memory-mapped interfaces:

Component	Frame	Offset	Instance
GIC Redistributor	RD_base	0x0048	GICR_CLRLPIR

Accesses to this register are WO.

2026-03-12 12:23:09, 2025-09_rel_asl1