Difference between revisions of "Unit BootRPi"
| (3 intermediate revisions by the same user not shown) | |||
| Line 13: | Line 13: | ||
CPU: ARM1176 (ARMv6) (1 @ 700MHz) | CPU: ARM1176 (ARMv6) (1 @ 700MHz) | ||
| − | Cache: L1 16KB / L2 128KB (Shared with GPU) | + | Cache: L1 16KB/L2 128KB (Shared with GPU) |
FPU: VFPV2 | FPU: VFPV2 | ||
| Line 23: | Line 23: | ||
USB: Synopsys DesignWare Hi-Speed USB 2.0 On-The-Go Controller (DWCOTG) | USB: Synopsys DesignWare Hi-Speed USB 2.0 On-The-Go Controller (DWCOTG) | ||
| − | LAN: SMSC LAN9512 (SMSC LAN9514 on Model B+ / No LAN on Model A/A+/Zero) (SMSC95XX) | + | LAN: SMSC LAN9512 (SMSC LAN9514 on Model B+/No LAN on Model A/A+/Zero) (SMSC95XX) |
SD/MMC: Arasan (BCM2708) | SD/MMC: Arasan (BCM2708) | ||
| Line 31: | Line 31: | ||
Bluetooth: (None) | Bluetooth: (None) | ||
| − | Other: GPIO / SPI / I2C / I2S / PL011 (UART) / PWM / SMI / Watchdog (PM) / Random (RNG) / Timer | + | Other: GPIO/SPI/I2C/I2S/PL011 (UART)/PWM/SMI/Watchdog (PM)/Random (RNG)/Timer |
| + | |||
'''Boot RPi''' | '''Boot RPi''' | ||
| Line 60: | Line 61: | ||
Unaligned Data Access - Disabled | Unaligned Data Access - Disabled | ||
| + | |||
Ultibo switches the processor to System mode for all operations and remains in the Secure world. | Ultibo switches the processor to System mode for all operations and remains in the Secure world. | ||
| Line 87: | Line 89: | ||
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;"> | <div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;"> | ||
| − | <pre style="border: 0; padding-bottom:0px;">procedure Startup; assembler; nostackframe; | + | <pre style="border: 0; padding-bottom:0px;">procedure Startup; assembler; nostackframe; public name '_START';</pre> |
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Entry point of Ultibo on Raspberry Pi, this will be the very first byte executed and will be loaded by the GPU at address 0x00008000</div> | <div style="font-size: 14px; padding-left: 12px;">'''Description:''' Entry point of Ultibo on Raspberry Pi, this will be the very first byte executed and will be loaded by the GPU at address 0x00008000</div> | ||
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;"> | <div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;"> | ||
{| class="wikitable" style="font-size: 14px; background: white;" | {| class="wikitable" style="font-size: 14px; background: white;" | ||
|- | |- | ||
| − | ! | + | ! Note |
| None documented | | None documented | ||
|- | |- | ||
| Line 104: | Line 106: | ||
{| class="wikitable" style="font-size: 14px; background: white;" | {| class="wikitable" style="font-size: 14px; background: white;" | ||
|- | |- | ||
| − | ! | + | ! Note |
| See A2.6 "Exceptions" of the ARM Architecture Reference Manual | | See A2.6 "Exceptions" of the ARM Architecture Reference Manual | ||
|- | |- | ||
| Line 116: | Line 118: | ||
{| class="wikitable" style="font-size: 14px; background: white;" | {| class="wikitable" style="font-size: 14px; background: white;" | ||
|- | |- | ||
| − | ! | + | ! Note |
| None documented | | None documented | ||
|- | |- | ||
Latest revision as of 01:19, 22 April 2022
Return to Unit Reference
Description
Ultibo Initialization code for Raspberry Pi unit
Raspberry Pi
SoC: Broadcom BCM2835
CPU: ARM1176 (ARMv6) (1 @ 700MHz)
Cache: L1 16KB/L2 128KB (Shared with GPU)
FPU: VFPV2
GPU: Broadcom VideoCore IV (VC4)
RAM: 512MB (256MB on Model A/A+)
USB: Synopsys DesignWare Hi-Speed USB 2.0 On-The-Go Controller (DWCOTG)
LAN: SMSC LAN9512 (SMSC LAN9514 on Model B+/No LAN on Model A/A+/Zero) (SMSC95XX)
SD/MMC: Arasan (BCM2708)
WiFi: (None)
Bluetooth: (None)
Other: GPIO/SPI/I2C/I2S/PL011 (UART)/PWM/SMI/Watchdog (PM)/Random (RNG)/Timer
Boot RPi
The boot loader on the Raspberry Pi will load this code at address 0x00008000 onwards and set the following registers before jumping to this code.
R0 - Zero
R1 - Machine Type (Raspberry Pi or BCM2708 = 0x0c42)
R2 - Address of the ARM Tags structure (Normally 0x0100)
On entry to this code the processor will be in the following state:
World - Secure
Mode - Supervisor (ARM_MODE_SVC)
MMU - Disabled
FPU - Disabled
L1 Data Cache - Disabled
L1 Instruction Cache - Disabled
Branch Predication - Disabled
Unaligned Data Access - Disabled
Ultibo switches the processor to System mode for all operations and remains in the Secure world.
The initialization process enables the MMU, FPU, L1 Cache and other performance optimizations.
Constants
None defined
Type definitions
None defined
Public variables
None defined
Function declarations
Boot functions
procedure Startup; assembler; nostackframe; public name '_START';
| Note | None documented |
|---|
procedure Vectors; assembler; nostackframe;
| Note | See A2.6 "Exceptions" of the ARM Architecture Reference Manual |
|---|
procedure StartupHandler; assembler; nostackframe;
| Note | None documented |
|---|
Return to Unit Reference
