Unit PlatformARM
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Description
Ultibo Platform Interface unit for ARM
Constants
 ARM_MODE_* | Bits 4..0 in the ARM program status register | |
| See: A2.2 Processor Modes of the ARM Architecture Reference Manual and also A2.5.7 The mode bits | |
| See also: B1.3.1 ARM processor modes of the ARM Architecture Reference Manual (ARMv7-A and ARMv7-R edition) | |
 ARM_MODE_USR = $10;
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Normal User Mode | 
 ARM_MODE_FIQ = $11;
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FIQ Processing Fast Interrupts Mode | 
 ARM_MODE_IRQ = $12;
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IRQ Processing Standard Interrupts Mode | 
 ARM_MODE_SVC = $13;
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Supervisor Processing Software Interrupts Mode | 
 ARM_MODE_MON = $16;
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Secure Monitor Mode (For Secure/Non Secure Switching) | 
 ARM_MODE_MON = $16;
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Secure Monitor Mode (For Secure/Non Secure Switching) | 
 ARM_MODE_ABT = $17;
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Abort Processing memory Faults Mode | 
 ARM_MODE_HYP = $1A;
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Hypervisor Mode | 
 ARM_MODE_UND = $1B;
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Undefined Processing Undefined Instructions Mode | 
 ARM_MODE_SYS = $1F;
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System Running Priviledged Operating System Tasks Mode | 
 ARM_MODE_BITS = $0000001F;
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Mask of the mode bits in the program status register | 
 ARM_I_* | Bits 7 and 6 in the ARM program status register | |
| See: A2.5.6 "The interrupt disable bits" of the ARM Architecture Reference Manual | |
 ARM_I_BIT = $00000080;
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IRQs disabled when set to 1 | 
 ARM_F_BIT = $00000040;
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FIQs disabled when set to 1 | 
 ARM_*_BIT | Bits 24 and 5 in the ARM program status register | |
| See: A2.5.8 "The T and J bits" of the ARM Architecture Reference Manual | |
 ARM_T_BIT = $00000020;
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Thumb mode enabled when set to 1 | 
 ARM_J_BIT = $01000000;
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Jazelle mode enabled when set to 1 | 
 ARM_A_* | Bit 8 in the ARM program status register | |
 ARM_A_BIT = $00000100;
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Data Abort masked when set to 1 | 
 ATAG_*  ATAG_NONE = $00000000;
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|
 ATAG_CORE = $54410001;
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 ATAG_MEM = $54410002;
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 ATAG_VIDEOTEXT = $54410003;
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 ATAG_RAMDISK = $54410004;
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 ATAG_INITRD = $54410005;
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Deprecated | 
 ATAG_INITRD2 = $54420005;
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 ATAG_SERIAL = $54410006;
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 ATAG_REVISION = $54410007;
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 ATAG_VIDEOLFB = $54410008;
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 ATAG_CMDLINE = $54410009;
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 ARMTAGS_INITIAL = $FFFFFFFF;
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|
 DTB_*  DTB_SIGNATURE = $d00dfeed;
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See: https://github.com/devicetree-org/devicetree-specification/releases/download/v0.3/devicetree-specification-v0.3.pdf | 
 
 ARM_MACHINE_*  ARM_MACHINE_VERSATILE_PB = $00000183;
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|
 ARM_MACHINE_BCM2708 = $00000C42;
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 ARM_MACHINE_BCM2709 = $00000C42;
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BCM2709 uses the same Machine Type as BCM2708 | 
 ARM_MACHINE_BCM2710 = $00000C42;
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BCM2710 uses the same Machine Type as BCM2708 | 
 ARM_MACHINE_BCM2711 = $00000C42;
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BCM2711 uses the same Machine Type as BCM2708 | 
Type definitions
ARM boot tag header
PARMTagHeader = ^TARMTagHeader;
TARMTagHeader = record
| Note: ARM Boot Tag Structure Definitions | |
 Size:LongWord;
 | 
Size of tag, in words (32bit), including the header | 
 Tag:LongWord;
 | 
One of the ATAG_* values from above | 
ARM tag core
PARMTagCore = ^TARMTagCore;
TARMTagCore = record
| Note: Core parameters (ATAG_CORE) | |
 Flags:LongWord;
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Bit 0 = read-only | 
 PageSize:LongWord;
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Systems page size (usually 4k) | 
 RootDev:LongWord;
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Root device number | 
ARM tag memory
PARMTagMemory = ^TARMTagMemory;
TARMTagMemory = record
| Note: Description of memory region (ATAG_MEM) | |
 Size:LongWord;
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|
 Start:LongWord;
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|
ARM tag video text
PARMTagVideoText = ^TARMTagVideoText;
TARMTagVideoText = record
| Note: Description of VGA text type displays (ATAG_VIDEOTEXT) | |
 X:Byte;
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Width of display | 
 Y:Byte;
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Height of display | 
 Video_page:Word;
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 Video_mode:Byte;
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 Video_cols:Byte;
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 Video_ega_bx:Word;
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 Video_lines:Byte;
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 Video_isvga:Byte;
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 Video_points:Word;
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ARM tag ramdisk
PARMTagRamdisk = ^TARMTagRamdisk;
TARMTagRamdisk = record
| Note: Description of how the ramdisk will be used by the kernel (ATAG_RAMDISK) | |
 Flags:LongWord;
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Bit 0 = load, Bit 1 = prompt | 
 Size:LongWord;
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Decompressed ramdisk size in _kilo_ bytes | 
 Start:LongWord;
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Starting block of floppy-based RAM disk image | 
Tag initialize RD
 TagInitRdCount:LongWord;
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Number of ARM INITRD Tags found during parse (Deprecated) | 
Tag initialize RD2
 TagInitRd2Count:LongWord;
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Number of ARM INITRD2 Tags found during parse | 
 TagInitRd2Start:LongWord;
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 TagInitRd2Size:LongWord;
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ARM tag serial
PARMTagSerial = ^TARMTagSerial;
TARMTagSerial = record
| Note: Board serial number (ATAG_SERIAL) | |
 Low:LongWord;
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|
 High:LongWord;
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ARM tag revision
PARMTagRevision = ^TARMTagRevision;
TARMTagRevision = record
| Note: Board revision (ATAG_REVISION) | |
 Revision:LongWord;
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|
ARM tag video framebuffer
PARMTagVideoFB = ^TARMTagVideoFB;
TARMTagVideoFB = record
| Note: Description of the parameters for a linear framebuffer type display (ATAG_VIDEOLFB) | |
 Lfb_width:Word;
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 Lfb_height:Word;
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 Lfb_depth:Word;
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 Lfb_linelength:Word;
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 Lfb_base:LongWord;
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 Lfb_size:LongWord;
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 Red_size:Byte;
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 Red_pos:Byte;
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 Green_size:Byte;
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 Green_pos:Byte;
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 Blue_size:Byte;
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 Blue_pos:Byte;
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 Rsvd_size:Byte;
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 Rsvd_pos:Byte;
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ARM tag command
PARMTagCommand = ^TARMTagCommand;
TARMTagCommand = record
| Note: Commandline for the kernel (ATAG_CMDLINE) | |
 Cmdline:array[0..0] of AnsiChar;
 | 
This is the minimum size | 
ARM boot tag
PARMTag = ^TARMTag;
TARMTag = record
| Note: Format of ARM Boot Tag | |
 Header:TARMTagHeader;
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|
 case Integer of
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 0:(Core:TARMTagCore);
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 1:(Memory:TARMTagMemory);
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 2:(VideoText:TARMTagVideoText);
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 3:(Ramdisk:TARMTagRamdisk);
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 4:(InitRd2:TARMTagInitRd2);
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 5:(Serial:TARMTagSerial);
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 6:(Revision:TARMTagRevision);
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 7:(VideoFB:TARMTagVideoFB);
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 8:(Command:TARMTagCommand)
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Device tree blob header
PDTBHeader = ^TDTBHeader;
TDTBHeader = packed record
 Magic:LongWord;
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The value 0xd00dfeed (big-endian) | 
 TotalSize:LongWord;
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The total size in bytes of the devicetree data structure (big-endian) | 
 StructureOffset:LongWord;
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The offset in bytes of the structure block from the beginning of the header (big-endian) | 
 StringsOffset:LongWord;
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The offset in bytes of the strings block from the beginning of the header (big-endian) | 
 ReservationOffset:LongWord;
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The offset in bytes of the memory reservation block from the beginning of the header (big-endian) | 
 Version:LongWord;
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The version of the devicetree data structure (big-endian) | 
 CompatibleVersion:LongWord;
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The lowest version of the devicetree data structure with which the version used is backwards compatible (big-endian) | 
 BootCPUID:LongWord;
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The physical ID of the system’s boot CPU (big-endian) | 
 StringsSize:LongWord;
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The length in bytes of the strings block section of the devicetree blob (big-endian) | 
 StructureSize:LongWord;
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The length in bytes of the structure block section of the devicetree blob (big-endian) | 
ARM wait
 TARMWait = procedure;
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ARM long wait
 TARMLongWait = procedure;
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ARM short wait
 TARMShortWait = procedure;
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ARM slow blink
 TARMSlowBlink = procedure;
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ARM fast blink
 TARMFastBlink = procedure;
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Public variables
ARM specific variables
 ARMInitialized:Boolean;
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 ARMBootMode:LongWord = 0;
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The ARM Mode that the processor was in at boot time (Set by Startup) | 
 ARMBootVectors:LongWord = 0;
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The Vector Base Address that was current at boot time (Set by Startup) | 
 ARMTagsAddress:PtrUInt = ARMTAGS_INITIAL;
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Pointer to the ARM TAGS provided by the bootloader at startup (Set by Startup) | 
 ARMMachineType:LongWord = 0;
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ARM Machine Type provided by the bootloader at startup (Set by Startup) | 
 ARMSecureBoot:LongWord = 1;
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If 1 then startup will attempt to switch back to secure world during boot process (If supported by the ARM boot stub) | 
 ARMEmulatorMode:LongWord = 0;
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If 1 then startup detected that the machine is running in an emulator (If applicable)
 Note: These variables must be initialized to remain in .data or else they are rewritten to zero with .bss  | 
ARM tags
 ARMTagsCount:LongWord;
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Number of ARM Tags found during parse | 
Tag none variables
 TagNoneCount:LongWord;
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Number of ARM NONE Tags found during parse | 
Tag core
 TagCoreCount:LongWord;
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Number of ARM CORE Tags found during parse | 
 TagCoreFlags:LongWord;
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 TagCorePageSize:LongWord;
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 TagCoreRootDevice:LongWord;
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Tag memory
 TagMemoryCount:LongWord;
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Number of ARM MEM Tags found during parse | 
 TagMemorySize:LongWord;
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Size of the last block reported by ARM Tags | 
 TagMemoryStart:PtrUInt;
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Start of the last block reported by ARM Tags | 
 TagMemoryLength:LongWord;
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Adjusted Size of the last block reported by ARM Tags | 
 TagMemoryAddress:PtrUInt;
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Adjusted Address of the last block reported by ARM Tags | 
Tag video text
 TagVideoTextCount:LongWord;
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Number of ARM VIDEOTEXT Tags found during parse | 
Tag ramdisk
 TagRamdiskCount:LongWord;
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Number of ARM RAMDISK Tags found during parse | 
Tag initialize RD2
 TagInitRd2Count:LongWord;
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Number of ARM INITRD2 Tags found during parse | 
Tag serial
 TagSerialCount:LongWord;
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Number of ARM SERIAL Tags found during parse | 
 TagSerialNoLow:LongWord;
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 TagSerialNoHigh:LongWord;
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Tag revision
 TagRevisionCount:LongWord;
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Number of ARM REVISION Tags found during parse | 
 TagRevisionNo:LongWord;
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Tag video framebuffer
 TagVideoFBCount:LongWord;
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Number of ARM VIDEOLFB Tags found during parse | 
Tag command
 TagCmdCount:LongWord;
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Number of ARM CMDLINE Tags found during parse | 
 TagCommandSize:LongWord;
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Length of the command line in characters (Including null terminator) | 
 TagCommandCount:LongInt;
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Count of parameters (space delimited) in the command line | 
 TagCommandAddress:PAnsiChar;
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Pointer to the start of the command line | 
Wait handlers
 ARMWaitHandler:TARMWait;
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 ARMLongWaitHandler:TARMLongWait;
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 ARMShortWaitHandler:TARMShortWait;
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Blink handlers
 ARMSlowBlinkHandler:TARMSlowBlink;
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 ARMFastBlinkHandler:TARMFastBlink;
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Function declarations
Initialization functions
procedure ARMInit;
| Note | None documented | 
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ARM platform functions
procedure ARMParseBootTags;
| Note | None documented | 
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function ExtractCommandLine(Value:PAnsiChar):Boolean;
| Note | None documented | 
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function ExtractMemoryBlock(Address,Size:LongWord):Boolean;
| Note | None documented | 
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function ExtractInitialRamdisk(Address,Size:LongWord):Boolean;
| Note | None documented | 
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procedure ARMParseCommandLine;
| Note | None documented | 
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procedure ARMParseEnvironment;
| Note | None documented | 
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function ARMGetSP:PtrUInt; assembler; nostackframe;
| Note | None documented | 
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function ARMGetPC:PtrUInt; assembler; nostackframe;
| Note | None documented | 
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function ARMGetIRQ:Boolean; assembler; nostackframe;
| Return | True is enabled, False if disabled (Returned in R0). | 
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procedure ARMEnableIRQ; assembler; nostackframe;
| Note | None documented | 
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procedure ARMDisableIRQ; assembler; nostackframe;
| Note | None documented | 
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function ARMSaveIRQ:TIRQMask; assembler; nostackframe;
| Return | IRQ state when called (Returned in R0) | 
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function ARMRestoreIRQ(IRQMask:TIRQMask):TIRQMask; assembler; nostackframe;
| IRQMask | IRQ state to restore (Passed in R0) | 
|---|---|
| Return | IRQ state when called (Returned in R0) | 
function ARMGetFIQ:Boolean; assembler; nostackframe;
| Return | True is enabled, False if disabled (Returned in R0). | 
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procedure ARMEnableFIQ; assembler; nostackframe;
| Note | None documented | 
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procedure ARMDisableFIQ; assembler; nostackframe;
| Note | None documented | 
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function ARMSaveFIQ:TFIQMask; assembler; nostackframe;
| Return | FIQ state when called (Returned in R0) | 
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function ARMRestoreFIQ(FIQMask:TFIQMask):TFIQMask; assembler; nostackframe;
| FIQMask | FIQ state to restore (Passed in R0) | 
|---|---|
| Return | FIQ state when called (Returned in R0) | 
procedure ARMEnableIRQFIQ; assembler; nostackframe;
| Note | None documented | 
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procedure ARMDisableIRQFIQ; assembler; nostackframe;
| Note | None documented | 
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function ARMSaveIRQFIQ:TIRQFIQMask; assembler; nostackframe;
| Return | IRQ/FIQ state when called (Returned in R0) | 
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function ARMRestoreIRQFIQ(IRQFIQMask:TIRQFIQMask):TIRQFIQMask; assembler; nostackframe;
| IRQFIQMask | IRQ/FIQ state to restore (Passed in R0) | 
|---|---|
| Return | IRQ/FIQ state when called (Returned in R0) | 
function ARMGetAbort:Boolean; assembler; nostackframe;
| Return | True is enabled, False if disabled (Returned in R0). | 
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procedure ARMEnableAbort; assembler; nostackframe;
| Note | None documented | 
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procedure ARMDisableAbort; assembler; nostackframe;
| Note | None documented | 
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function ARMSaveAbort:TAbortMask; assembler; nostackframe;
| Return | Abort state when called (Returned in R0) | 
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function ARMRestoreAbort(AbortMask:TAbortMask):TAbortMask; assembler; nostackframe;
| AbortMask | Abort state to restore (Passed in R0) | 
|---|---|
| Return | Abort state when called (Returned in R0) | 
ARM helper functions
procedure ARMWait; inline;
| Note | None documented | 
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procedure ARMLongWait; inline;
| Note | None documented | 
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procedure ARMShortWait; inline;
| Note | None documented | 
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procedure ARMSlowBlink; inline;
| Note | None documented | 
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procedure ARMFastBlink; inline;
| Note | None documented | 
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function ARMModeToString(ARMMode:LongWord):String;
| Note | None documented | 
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