Data in Huge Data Memory Space
[Utility Library]

Collaboration diagram for Data in Huge Data Memory Space:

Modules
	Hugemem implementation for 8-bit AVR.
Defines
#define	HUGEMEM_NULL   0
	Hugemem null pointer, similar to NULL, but works across different platforms.
Typedefs
typedef uint32_t	hugemem_ptr_t
	Type to use for pointers to huge memory.
Functions
hugemem_ptr_t	hugemem_alloc (struct physmem_pool *pool, phys_size_t size, unsigned int align_order)
	Allocate a region of huge memory.
static uint_fast8_t	hugemem_read8 (const hugemem_ptr_t from)
	Read 8-bit value stored at huge memory address from.
uint_fast16_t	hugemem_read16 (const hugemem_ptr_t from)
	Read 16-bit value stored at huge memory address from.
uint_fast32_t	hugemem_read32 (const hugemem_ptr_t from)
	Read 32-bit value stored at huge memory address from.
static void	hugemem_write8 (hugemem_ptr_t to, uint_fast8_t val)
	Write 8-bit value val to huge memory address to.
void	hugemem_write16 (hugemem_ptr_t to, uint_fast16_t val)
	Write 16-bit value val to huge memory address to.
void	hugemem_write32 (hugemem_ptr_t to, uint_fast32_t val)
	Write 32-bit value val to huge memory address to.
void	hugemem_read_block (void *to, const hugemem_ptr_t from, size_t size)
	Read size bytes from huge memory address from into buffer at address to.
void	hugemem_write_block (hugemem_ptr_t to, const void *from, size_t size)
	Write size bytes from buffer at address from to huge memory address to.

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Detailed Description

Due to shortcomings of the GCC compiler for 8-bit AVR, custom functions are needed for access to data beyond the 64 kB boundary, i.e., addresses that are larger than 16-bit.

The definition of huge memory space can differ between architectures, so the implementation is architecture specific.

This module supplies functions for copying a number of bytes between huge and 64 kB data memory space, and is needed solely for code compatibility across compilers.

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Define Documentation

#define HUGEMEM_NULL   0

Hugemem null pointer, similar to NULL, but works across different platforms.

Definition at line 66 of file hugemem.h.

Referenced by app_fonts_load(), hugemem_alloc(), and tank_loader().

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Typedef Documentation

hugemem_ptr_t

Type to use for pointers to huge memory.

Definition at line 64 of file hugemem.h.

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Function Documentation

hugemem_ptr_t hugemem_alloc	(	struct physmem_pool *	pool,
		phys_size_t	size,
		unsigned int	align_order
	)

Allocate a region of huge memory.

This function tries to allocate a block of huge memory from the given pool, at the highest possible address.

Parameters:

	pool	The huge memory pool to allocate from.
	size	The number of bytes to allocate.
	align_order	log2 of required alignment.

Returns:

A valid hugemem address, or HUGEMEM_NULL if there isn't sufficient memory available.

Precondition:

Not in interrupt context.

Definition at line 55 of file hugemem.c.

References HUGEMEM_NULL, physmem_alloc(), and PHYSMEM_ALLOC_ERR.

uint_fast16_t hugemem_read16

(

const hugemem_ptr_t

from

)

Read 16-bit value stored at huge memory address from.

Definition at line 44 of file arch_hugemem.c.

References CPU_REG.

uint_fast32_t hugemem_read32

(

const hugemem_ptr_t

from

)

Read 32-bit value stored at huge memory address from.

Definition at line 62 of file arch_hugemem.c.

References CPU_REG.

uint_fast8_t hugemem_read8

(

const hugemem_ptr_t

from

)

[inline, static]

Read 8-bit value stored at huge memory address from.

Definition at line 68 of file hugemem.h.

References CPU_REG.

Referenced by gfx_copy_hugemem_pixels_to_screen().

void hugemem_read_block	(	void *	to,
		const hugemem_ptr_t	from,
		size_t	size
	)

Read size bytes from huge memory address from into buffer at address to.

Definition at line 82 of file arch_hugemem.c.

References assert, and CPU_REG.

Referenced by app_files_load_worker(), app_fonts_load_worker(), and gfx_draw_char_hugemem().

void hugemem_write16	(	hugemem_ptr_t	to,
		uint_fast16_t	val
	)

Write 16-bit value val to huge memory address to.

Definition at line 104 of file arch_hugemem.c.

References CPU_REG.

void hugemem_write32	(	hugemem_ptr_t	to,
		uint_fast32_t	val
	)

Write 32-bit value val to huge memory address to.

Definition at line 118 of file arch_hugemem.c.

References CPU_REG.

void hugemem_write8	(	hugemem_ptr_t	to,
		uint_fast8_t	val
	)			[inline, static]

Write 8-bit value val to huge memory address to.

Definition at line 88 of file hugemem.h.

References CPU_REG.

void hugemem_write_block	(	hugemem_ptr_t	to,
		const void *	from,
		size_t	size
	)

Write size bytes from buffer at address from to huge memory address to.

Definition at line 134 of file arch_hugemem.c.

References assert, and CPU_REG.

Referenced by load_to_hugemem_worker().