Bcm2837

The SoC of the Raspberry Pi 3 Model B+ is the Broadcom BCM2837B0. More...

Functions
void	add_mailbox_tag (volatile uint32_t *buffer, uint32_t tag, uint32_t buflen, uint32_t len, uint32_t *data)
void	build_mailbox_request (volatile uint32_t *mailbuffer)
void	get_mac_mailbox (volatile uint32_t *mailbuffer)
void	bcm2837_mailbox_write (uint channel, uint value)
uint	bcm2837_mailbox_read (uint channel)
int	bcm2837_setpower (enum board_power_feature feature, bool on)
void	bcm2837_power_init (void)
unsigned int	mmu_section (unsigned int vadd, unsigned int padd, unsigned int flags)
void	mmu_init ()
void	led_init (void)
void	led_on (void)
void	led_off (void)
int	platforminit (void)
void *	setupStack (void *stackaddr, void *procaddr, void *retaddr, uint nargs, va_list ap)
void	CoreSetup (void)
void	createnullthread (void)

Detailed Description

The SoC of the Raspberry Pi 3 Model B+ is the Broadcom BCM2837B0.

While much of Embedded Xinu's port has been redesigned for the BCM2837B0 (bootloader, multicore capability, L1 cache, to name a few), there are remnants of the last port (BCM2835 Raspberry Pi 1) in this operating system as the entire wheel need not be reinvented.

Function Documentation

void add_mailbox_tag	(	volatile uint32_t *	buffer,
		uint32_t	tag,
		uint32_t	buflen,
		uint32_t	len,
		uint32_t *	data
	)

Add a tag to the mailbox buffer. This step must be done before a mailbox request is built.

Parameters

buffer	Mailbox buffer
tag	Tag to pass
buflen	Buffer length
len	Length of data to be sent
data	Data to be sent

uint bcm2837_mailbox_read

(

uint

channel

)

Read from the specified channel of the mailbox.

Parameters

channel

Mailbox channel to read from

Returns

Value read from the mailbox

void bcm2837_mailbox_write	(	uint	channel,
		uint	value
	)

Write to the specified channel of the mailbox.

Parameters

channel	Mailbox channel to write to
value	Value to write to the mailbox

void bcm2837_power_init

(

void

)

Resets BCM2837 power to default state (all devices powered off).

int bcm2837_setpower	(	enum board_power_feature	feature,
		bool	on
	)

Powers on or powers off BCM2837 hardware.

Parameters

feature	Device or hardware to power on or off.
on	::TRUE to power on; ::FALSE to power off.

Returns

::OK if successful; ::SYSERR otherwise.

void build_mailbox_request

(

volatile uint32_t *

mailbuffer

)

Ready the buffer by initializing proper lengths, slots.

Parameters

mailbuffer

Mailbox buffer

void createnullthread

(

void

)

Create a null thread (for testing purposes -> should be taken out)

void get_mac_mailbox

(

volatile uint32_t *

mailbuffer

)

Function for getting the MAC address using the corresponding MAC mailbox tag.

Parameters

mailbuffer

Mailbox buffer written with MAC address upon conclusion.

void led_init

(

void

)

This code is irrelevant to Embedded Xinu and is only used as a means of testing on the RPI 3 boards

Initialize GPIO pin 16 as an output

void led_off

(

void

)

Set GPIO pin 16 to OFF

void led_on

(

void

)

Set GPIO pin 16 to ON

void mmu_init

(

void

)

mmu_init() configures virtual address == physical address also configures memory to be cacheable, except for peripheral portion

unsigned int mmu_section	(	unsigned int	vadd,
		unsigned int	padd,
		unsigned int	flags
	)

Mark a section of memory as cacheable, given flags

Parameters

vadd	Virtual address
padd	Physical address
flags	Flag to mark the section

Returns

Zero

int platforminit

(

void

)

Initializes platform specific information for the Raspberry Pi hardware.

Returns

OK

void* setupStack	(	void *	stackaddr,
		void *	procaddr,
		void *	retaddr,
		uint	nargs,
		va_list	ap
	)

Set up the context record and arguments on the stack for a new thread (ARM version)

Parameters

stackaddr	Stack address
procaddr	Process address

Returns

Top of the stack