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5 mmu test registers and operations, Mmu test registers and operations -8, Mmu test registers and operations – Epson ARM.POWERED ARM720T User Manual

Page 192

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11: Test Support

11-8

EPSON

ARM720T CORE CPU MANUAL

; Now read and check

MOV r8,#8
MOV r2,#0x10
MOV r1,#0

loop1

MCR p15,3,r1,c15,c3,0

; write C15.C to ‘0’

MCR p15,2,r2,c15,c11,2

; read RAM to C15.C

MRC p15,3,r5,c15,c3,0

; read C15.C to R4

ADD r2,r2,#0x04
CMP r5,r0
BNE TEST_FAIL
SUBS r8,r8,#1
BNE loop1
B TEST_PASS

11.5

MMU test registers and operations

The TLB is maintained using MCR and MRC instructions to CP15 registers c2, c3, c5, c6, c8,

and c10, defined by the ARM v4T programmer’s model.
The CP15 register c2 operations control the

Translation Table Base

(TTB). These operations

are:

write Translation Table Base Registers

read Translation Table Base Register.

The CP15 register c3 operations control the

Domain Access Control

(DAC) register. These

operations are:

write DAC registers

read DAC register.

The CP15 register c5 operations control the

Fault Status Register

(FSR). These operations are:

write FSR

read FSR.

The CP15 register c6 operations control the

Fault Address Register

(FAR). These operations

are:

write FAR

read FAR.

The CP15 register c8 operations control the TLB and are all write-only. These operations are:

invalidate TLB

invalidate single entry using MVA.

The CP15 register c10 operations control TLB lockdown. These operations are:

read victim, lockdown base and preserve bit

write victim, lockdown base and preserve bit.