audk/MdePkg/Library/BaseIoLibIntrinsic/Arm/ArmVirtMmio.asm

146 lines
3.6 KiB
NASM

;
; Copyright (c) 2014-2018, Linaro Limited. All rights reserved.
;
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
AREA IoLibMmio, CODE, READONLY
EXPORT MmioRead8Internal
EXPORT MmioWrite8Internal
EXPORT MmioRead16Internal
EXPORT MmioWrite16Internal
EXPORT MmioRead32Internal
EXPORT MmioWrite32Internal
EXPORT MmioRead64Internal
EXPORT MmioWrite64Internal
;
; Reads an 8-bit MMIO register.
;
; Reads the 8-bit MMIO register specified by Address. The 8-bit read value is
; returned. This function must guarantee that all MMIO read and write
; operations are serialized.
;
; @param Address The MMIO register to read.
;
; @return The value read.
;
MmioRead8Internal
ldrb r0, [r0]
dmb
bx lr
;
; Writes an 8-bit MMIO register.
;
; Writes the 8-bit MMIO register specified by Address with the value specified
; by Value and returns Value. This function must guarantee that all MMIO read
; and write operations are serialized.
;
; @param Address The MMIO register to write.
; @param Value The value to write to the MMIO register.
;
MmioWrite8Internal
dmb st
strb r1, [r0]
bx lr
;
; Reads a 16-bit MMIO register.
;
; Reads the 16-bit MMIO register specified by Address. The 16-bit read value is
; returned. This function must guarantee that all MMIO read and write
; operations are serialized.
;
; @param Address The MMIO register to read.
;
; @return The value read.
;
MmioRead16Internal
ldrh r0, [r0]
dmb
bx lr
;
; Writes a 16-bit MMIO register.
;
; Writes the 16-bit MMIO register specified by Address with the value specified
; by Value and returns Value. This function must guarantee that all MMIO read
; and write operations are serialized.
;
; @param Address The MMIO register to write.
; @param Value The value to write to the MMIO register.
;
MmioWrite16Internal
dmb st
strh r1, [r0]
bx lr
;
; Reads a 32-bit MMIO register.
;
; Reads the 32-bit MMIO register specified by Address. The 32-bit read value is
; returned. This function must guarantee that all MMIO read and write
; operations are serialized.
;
; @param Address The MMIO register to read.
;
; @return The value read.
;
MmioRead32Internal
ldr r0, [r0]
dmb
bx lr
;
; Writes a 32-bit MMIO register.
;
; Writes the 32-bit MMIO register specified by Address with the value specified
; by Value and returns Value. This function must guarantee that all MMIO read
; and write operations are serialized.
;
; @param Address The MMIO register to write.
; @param Value The value to write to the MMIO register.
;
MmioWrite32Internal
dmb st
str r1, [r0]
bx lr
;
; Reads a 64-bit MMIO register.
;
; Reads the 64-bit MMIO register specified by Address. The 64-bit read value is
; returned. This function must guarantee that all MMIO read and write
; operations are serialized.
;
; @param Address The MMIO register to read.
;
; @return The value read.
;
MmioRead64Internal
ldr r1, [r0, #4]
ldr r0, [r0]
dmb
bx lr
;
; Writes a 64-bit MMIO register.
;
; Writes the 64-bit MMIO register specified by Address with the value specified
; by Value and returns Value. This function must guarantee that all MMIO read
; and write operations are serialized.
;
; @param Address The MMIO register to write.
; @param Value The value to write to the MMIO register.
;
MmioWrite64Internal
dmb st
str r2, [r0]
str r3, [r0, #4]
bx lr
END