Unit PlatformARM

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Description

Ultibo Platform Interface unit for ARM

Constants


ARM mode 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; Normal User Mode
ARM_MODE_FIQ = $11; FIQ Processing Fast Interrupts Mode
ARM_MODE_IRQ = $12; IRQ Processing Standard Interrupts Mode
ARM_MODE_SVC = $13; Supervisor Processing Software Interrupts Mode
ARM_MODE_MON = $16; Secure Monitor Mode (For Secure/Non Secure Switching)
ARM_MODE_MON = $16; Secure Monitor Mode (For Secure/Non Secure Switching)
ARM_MODE_ABT = $17; Abort Processing memory Faults Mode
ARM_MODE_HYP = $1A; Hypervisor Mode
ARM_MODE_UND = $1B; Undefined Processing Undefined Instructions Mode
ARM_MODE_SYS = $1F; System Running Priviledged Operating System Tasks Mode
 
ARM_MODE_BITS = $0000001F; Mask of the mode bits in the program status register


ARM interrupt disable 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; IRQs disabled when set to 1
ARM_F_BIT = $00000040; FIQs disabled when set to 1


ARM thumb and jazelle 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; Thumb mode enabled when set to 1
ARM_J_BIT = $01000000; Jazelle mode enabled when set to 1


ARM abort ARM_A_*
Bit 8 in the ARM program status register
 
ARM_A_BIT = $00000100; Data Abort masked when set to 1


ARM boot tag ATAG_*
ATAG_NONE = $00000000;  
ATAG_CORE = $54410001;  
ATAG_MEM = $54410002;  
ATAG_VIDEOTEXT = $54410003;  
ATAG_RAMDISK = $54410004;  
ATAG_INITRD2 = $54410005;  
ATAG_SERIAL = $54410006;  
ATAG_REVISION = $54410007;  
ATAG_VIDEOLFB = $54410008;  
ATAG_CMDLINE = $54410009;  
 
ARMTAGS_INITIAL = $FFFFFFFF;  


ARM machine type ARM_MACHINE_*
ARM_MACHINE_VERSATILE_PB = $00000183;  
ARM_MACHINE_BCM2708 = $00000C42;  
ARM_MACHINE_BCM2709 = $00000C42; BCM2709 uses the same Machine Type as BCM2708
ARM_MACHINE_BCM2710 = $00000C42; BCM2710 uses the same Machine Type as BCM2708
ARM_MACHINE_BCM2711 = $00000C42; 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; Bit 0 = read-only
PageSize:LongWord; Systems page size (usually 4k)
RootDev:LongWord; Root device number

ARM tag memory

PARMTagMemory = ^TARMTagMemory;

TARMTagMemory = record

Note: Description of memory region (ATAG_MEM)
Size:LongWord;  
Start:LongWord;  

ARM tag video text

PARMTagVideoText = ^TARMTagVideoText;

TARMTagVideoText = record

Note: Description of VGA text type displays (ATAG_VIDEOTEXT)
X:Byte; Width of display
Y:Byte; Height of display
Video_page:Word;  
Video_mode:Byte;  
Video_cols:Byte;  
Video_ega_bx:Word;  
Video_lines:Byte;  
Video_isvga:Byte;  
Video_points:Word;  

ARM tag ramdisk

PARMTagRamdisk = ^TARMTagRamdisk;

TARMTagRamdisk = record

Note: Description of how the ramdisk will be used by the kernel (ATAG_RAMDISK)
Flags:LongWord; Bit 0 = load, Bit 1 = prompt
Size:LongWord; Decompressed ramdisk size in _kilo_ bytes
Start:LongWord; Starting block of floppy-based RAM disk image

ARM tag initialize ramdisk

PARMTagInitRd2 = ^TARMTagInitRd2;

TARMTagInitRd2 = record

Note: Description of the physical location of the compressed ramdisk image (ATAG_INITRD2)
Start:LongWord; Physical start address
Size:LongWord; Size of compressed ramdisk image in bytes

ARM tag serial

PARMTagSerial = ^TARMTagSerial;

TARMTagSerial = record

Note: Board serial number (ATAG_SERIAL)
Low:LongWord;  
High:LongWord;  

ARM tag revision

PARMTagRevision = ^TARMTagRevision;

TARMTagRevision = record

Note: Board revision (ATAG_REVISION)
Revision:LongWord;  

ARM tag video framebuffer

PARMTagVideoFB = ^TARMTagVideoFB;

TARMTagVideoFB = record

Note: Description of the parameters for a linear framebuffer type display (ATAG_VIDEOLFB)
Lfb_width:Word;  
Lfb_height:Word;  
Lfb_depth:Word;  
Lfb_linelength:Word;  
Lfb_base:LongWord;  
Lfb_size:LongWord;  
Red_size:Byte;  
Red_pos:Byte;  
Green_size:Byte;  
Green_pos:Byte;  
Blue_size:Byte;  
Blue_pos:Byte;  
Rsvd_size:Byte;  
Rsvd_pos:Byte;  

ARM tag command

PARMTagCommand = ^TARMTagCommand;

TARMTagCommand = record

Note: Commandline for the kernel (ATAG_CMDLINE)
Cmdline:array[0..0] of Char; This is the minimum size

ARM boot tag

PARMTag = ^TARMTag;

TARMTag = record

Note: Format of ARM Boot Tag
Header:TARMTagHeader;  
case Integer of  
0:(Core:TARMTagCore);  
1:(Memory:TARMTagMemory);  
2:(VideoText:TARMTagVideoText);  
3:(Ramdisk:TARMTagRamdisk);  
4:(InitRd2:TARMTagInitRd2);  
5:(Serial:TARMTagSerial);  
6:(Revision:TARMTagRevision);  
7:(VideoFB:TARMTagVideoFB);  
8:(Command:TARMTagCommand)  

ARM wait

TARMWait = procedure;

ARM long wait

TARMLongWait = procedure;

ARM short wait

TARMShortWait = procedure;

ARM slow blink

TARMSlowBlink = procedure;

ARM fast blink

TARMFastBlink = procedure;


Public variables


ARM specific variables

ARMInitialized:Boolean;
ARMBootMode:LongWord = 0; The ARM Mode that the processor was in at boot time (Set by Startup)
ARMBootVectors:LongWord = 0; The Vector Base Address that was current at boot time (Set by Startup)
ARMTagsAddress:PtrUInt = ARMTAGS_INITIAL; Pointer to the ARM TAGS provided by the bootloader at startup (Set by Startup)
ARMMachineType:LongWord = 0; ARM Machine Type provided by the bootloader at startup (Set by Startup)
ARMSecureBoot:LongWord = 1; 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; 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; Number of ARM Tags found during parse

Tag none variables

TagNoneCount:LongWord; Number of ARM NONE Tags found during parse

Tag core

TagCoreCount:LongWord; Number of ARM CORE Tags found during parse
TagCoreFlags:LongWord;
TagCorePageSize:LongWord;
TagCoreRootDevice:LongWord;

Tag memory

TagMemoryCount:LongWord; Number of ARM MEM Tags found during parse
TagMemorySize:LongWord; Size of the last block reported by ARM Tags
TagMemoryStart:PtrUInt; Start of the last block reported by ARM Tags
TagMemoryLength:LongWord; Adjusted Size of the last block reported by ARM Tags
TagMemoryAddress:PtrUInt; Adjusted Address of the last block reported by ARM Tags

Tag video text

TagVideoTextCount:LongWord; Number of ARM VIDEOTEXT Tags found during parse

Tag ramdisk

TagRamdiskCount:LongWord; Number of ARM RAMDISK Tags found during parse

Tag initialize RD2

TagInitRd2Count:LongWord; Number of ARM INITRD2 Tags found during parse

Tag serial

TagSerialCount:LongWord; Number of ARM SERIAL Tags found during parse
TagSerialNoLow:LongWord;
TagSerialNoHigh:LongWord;

Tag revision

TagRevisionCount:LongWord; Number of ARM REVISION Tags found during parse
TagRevisionNo:LongWord;

Tag video framebuffer

TagVideoFBCount:LongWord; Number of ARM VIDEOLFB Tags found during parse

Tag command

TagCmdCount:LongWord; Number of ARM CMDLINE Tags found during parse
TagCommandSize:LongWord; Length of the command line in characters (Including null terminator)
TagCommandCount:LongInt; Count of parameters (space delimited) in the command line
TagCommandAddress:PChar; Pointer to the start of the command line

Wait handlers

ARMWaitHandler:TARMWait;
ARMLongWaitHandler:TARMLongWait;
ARMShortWaitHandler:TARMShortWait;

Blink handlers

ARMSlowBlinkHandler:TARMSlowBlink;
ARMFastBlinkHandler:TARMFastBlink;


Function declarations


Initialization functions 

procedure ARMInit;
Description: To be documented
Note None documented


ARM platform functions 

procedure ARMParseBootTags;
Description: Extract some information from the ARM boot tag list and use it to load the memory manager, some other information is stored in variables for future use
Note None documented 


procedure ARMParseCommandLine;
Description: Setup argc, argv and cmdline and process known command line options
Note None documented 


procedure ARMParseEnvironment;
Description: Setup envp and process known environment options
Note None documented 


function ARMGetSP:PtrUInt; assembler; nostackframe;
Description: Get the current stack pointer (SP)
Note None documented 


function ARMGetPC:PtrUInt; assembler; nostackframe;
Description: Get the current program counter (PC)
Note None documented 


function ARMGetIRQ:Boolean; assembler; nostackframe;
Description: Get Interrupts (IRQ) state
Return True is enabled, False if disabled (Returned in R0). 


procedure ARMEnableIRQ; assembler; nostackframe;
Description: Enable Interrupts (IRQ) unconditionally
Note None documented 


procedure ARMDisableIRQ; assembler; nostackframe;
Description: Disable Interrupts (IRQ) unconditionally
Note None documented 


function ARMSaveIRQ:TIRQMask; assembler; nostackframe;
Description: Disable Interrupts (IRQ) and return the previous state
Return IRQ state when called (Returned in R0) 


function ARMRestoreIRQ(IRQMask:TIRQMask):TIRQMask; assembler; nostackframe;
Description: Restore Interrupts (IRQ) to a previous state
IRQMask IRQ state to restore (Passed in R0)
Return IRQ state when called (Returned in R0) 


function ARMGetFIQ:Boolean; assembler; nostackframe;
Description: Get Fast Interrupts (FIQ) state
Return True is enabled, False if disabled (Returned in R0). 


procedure ARMEnableFIQ; assembler; nostackframe;
Description: Enable Fast Interrupts (FIQ) unconditionally
Note None documented 


procedure ARMDisableFIQ; assembler; nostackframe;
Description: Disable Fast Interrupts (FIQ) unconditionally
Note None documented 


function ARMSaveFIQ:TFIQMask; assembler; nostackframe;
Description: Disable Fast Interrupts (FIQ) and return the previous state
Return FIQ state when called (Returned in R0) 


function ARMRestoreFIQ(FIQMask:TFIQMask):TFIQMask; assembler; nostackframe;
Description: Restore Fast Interrupts (FIQ) to a previous state
FIQMask FIQ state to restore (Passed in R0)
Return FIQ state when called (Returned in R0) 


procedure ARMEnableIRQFIQ; assembler; nostackframe;
Description: Enable Interrupts and Fast Interrupts (IRQ/FIQ) unconditionally
Note None documented 


procedure ARMDisableIRQFIQ; assembler; nostackframe;
Description: Disable Interrupts and Fast Interrupts (IRQ/FIQ) unconditionally
Note None documented 


function ARMSaveIRQFIQ:TIRQFIQMask; assembler; nostackframe;
Description: Disable Interrupts and Fast Interrupts (IRQ/FIQ) and return the previous state
Return IRQ/FIQ state when called (Returned in R0) 


function ARMRestoreIRQFIQ(IRQFIQMask:TIRQFIQMask):TIRQFIQMask; assembler; nostackframe;
Description: Restore Interrupts and Fast Interrupts (IRQ/FIQ) to a previous state
IRQFIQMask IRQ/FIQ state to restore (Passed in R0)
Return IRQ/FIQ state when called (Returned in R0) 


function ARMGetAbort:Boolean; assembler; nostackframe;
Description: Get Abort state
Return True is enabled, False if disabled (Returned in R0). 


procedure ARMEnableAbort; assembler; nostackframe;
Description: Enable Aborts unconditionally
Note None documented 


procedure ARMDisableAbort; assembler; nostackframe;
Description: Disable Aborts unconditionally
Note None documented 


function ARMSaveAbort:TAbortMask; assembler; nostackframe;
Description: Disable Aborts and return the previous state
Return Abort state when called (Returned in R0) 


function ARMRestoreAbort(AbortMask:TAbortMask):TAbortMask; assembler; nostackframe;
Description: Restore Aborts to a previous state
AbortMask Abort state to restore (Passed in R0)
Return Abort state when called (Returned in R0)


ARM helper functions 

procedure ARMWait; inline;
Description: To be documented
Note None documented 


procedure ARMLongWait; inline;
Description: To be documented
Note None documented 


procedure ARMShortWait; inline;
Description: To be documented
Note None documented 


procedure ARMSlowBlink; inline;
Description: To be documented
Note None documented 


procedure ARMFastBlink; inline;
Description: To be documented
Note None documented 


function ARMModeToString(ARMMode:LongWord):String;
Description: To be documented
Note None documented


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