MEMORY - MPU - Memory Protection Unit

MPU driver that allows the user to divide the memory space into different protection regions.

Modules
	Related Project(s)
	In this section you can find all the projects related to the MEMORY - MPU - Memory Protection Unit.

Data Structures
struct	mpu_entry_t

Macros
#define	CAST(to, from)

Enumerations
enum	eRegionSize {   MPU_REGION_SIZE_LOWLIMIT_FORBIDDEN = 10,   MPU_REGION_SIZE_4KB,   MPU_REGION_SIZE_8KB,   MPU_REGION_SIZE_16KB,   MPU_REGION_SIZE_32KB,   MPU_REGION_SIZE_64KB,   MPU_REGION_SIZE_128KB,   MPU_REGION_SIZE_256KB,   MPU_REGION_SIZE_512KB,   MPU_REGION_SIZE_1MB,   MPU_REGION_SIZE_2MB,   MPU_REGION_SIZE_4MB,   MPU_REGION_SIZE_8MB,   MPU_REGION_SIZE_16MB,   MPU_REGION_SIZE_32MB,   MPU_REGION_SIZE_64MB,   MPU_REGION_SIZE_128MB,   MPU_REGION_SIZE_256MB,   MPU_REGION_SIZE_512MB,   MPU_REGION_SIZE_1GB,   MPU_REGION_SIZE_2GB,   MPU_REGION_SIZE_4GB,   MPU_REGION_SIZE_HIGHLIMIT_FORBIDDEN }

Functions
void	disable_mpu (void)
	Disable the memory protection unit. MPU address checking is disabled, no exceptions will be generated by the MPU. More...
void	disable_mpu_entry (unsigned int region_number, unsigned int register_select)
void	enable_mpu (void)
	Enable the memory protection unit. MPU address checking is enabled. More...
bool	mpu_convert_kbsize_to_eregionsize (eRegionSize *peRegionSizeValue, U32 kBSizeValue)
	Converts an input region size expressed in kBytes to the corresponding eRegionSize type value. More...
void	select_subregion (unsigned int region_number, unsigned int pattern_select)
void	set_access_permissions (unsigned int region_number, unsigned int register_select, unsigned int right_access)
char	set_mpu_entry (const mpu_entry_t *mpu_entry, unsigned int region_number)
#define	MPU_APRA_ID   0
	MPU Access Permission Register A & B identifiers. More...
#define	MPU_APRB_ID   1
#define	MPU_PRIVR_UNPRIVNONE   AVR32_MPUAPRA_AP0_PRIV_R_UNPRIV_NONE
	MPU Access Permissions. More...
#define	MPU_PRIVRX_UNPRIVNONE   AVR32_MPUAPRA_AP0_PRIV_RX_UNPRIV_NONE
#define	MPU_PRIVRW_UNPRIVNONE   AVR32_MPUAPRA_AP0_PRIV_RW_UNPRIV_NONE
#define	MPU_PRIVRWX_UNPRIVNONE   AVR32_MPUAPRA_AP0_PRIV_RWX_UNPRIV_NONE
#define	MPU_PRIVR_UNPRIVR   AVR32_MPUAPRA_AP0_PRIV_R_UNPRIV_R
#define	MPU_PRIVRX_UNPRIVRX   AVR32_MPUAPRA_AP0_PRIV_RX_UNPRIV_RX
#define	MPU_PRIVRW_UNPRIVRW   AVR32_MPUAPRA_AP0_PRIV_RW_UNPRIV_RW
#define	MPU_PRIVRWX_UNPRIVRWX   AVR32_MPUAPRA_AP0_PRIV_RWX_UNPRIV_RWX
#define	MPU_PRIVRW_UNPRIVR   AVR32_MPUAPRA_AP0_PRIV_RW_UNPRIV_R
#define	MPU_PRIVRW_UNPRIVRX   AVR32_MPUAPRA_AP0_PRIV_RW_UNPRIV_RX
#define	MPU_PRIVNONE_UNPRIVNONE   AVR32_MPUAPRA_AP0_PRIV_NONE_UNPRIV_NONE
#define	MPU_SETUP_ENTRY_OK   0
	MPU entry set up function (set_mpu_entry) return codes. More...
#define	MPU_SETUP_ENTRY_INVALIDBASEADDR   1
#define	MPU_SETUP_ENTRY_INVALIDSIZE   2

#define CAST	(		to,
			from
	)

Value:

({                                     \
    typeof(from) __temp__ = from;        \
    to = *(typeof(to) *)&__temp__;       \
  })

#define MPU_APRA_ID   0

MPU Access Permission Register A & B identifiers.

Referenced by configure_memory_area().

#define MPU_APRB_ID   1

Referenced by configure_memory_area().

#define MPU_PRIVNONE_UNPRIVNONE   AVR32_MPUAPRA_AP0_PRIV_NONE_UNPRIV_NONE

#define MPU_PRIVR_UNPRIVNONE   AVR32_MPUAPRA_AP0_PRIV_R_UNPRIV_NONE

MPU Access Permissions.

Referenced by configure_memory_area().

#define MPU_PRIVR_UNPRIVR   AVR32_MPUAPRA_AP0_PRIV_R_UNPRIV_R

#define MPU_PRIVRW_UNPRIVNONE   AVR32_MPUAPRA_AP0_PRIV_RW_UNPRIV_NONE

Referenced by configure_memory_area().

#define MPU_PRIVRW_UNPRIVR   AVR32_MPUAPRA_AP0_PRIV_RW_UNPRIV_R

#define MPU_PRIVRW_UNPRIVRW   AVR32_MPUAPRA_AP0_PRIV_RW_UNPRIV_RW

#define MPU_PRIVRW_UNPRIVRX   AVR32_MPUAPRA_AP0_PRIV_RW_UNPRIV_RX

#define MPU_PRIVRWX_UNPRIVNONE   AVR32_MPUAPRA_AP0_PRIV_RWX_UNPRIV_NONE

#define MPU_PRIVRWX_UNPRIVRWX   AVR32_MPUAPRA_AP0_PRIV_RWX_UNPRIV_RWX

#define MPU_PRIVRX_UNPRIVNONE   AVR32_MPUAPRA_AP0_PRIV_RX_UNPRIV_NONE

#define MPU_PRIVRX_UNPRIVRX   AVR32_MPUAPRA_AP0_PRIV_RX_UNPRIV_RX

Referenced by configure_memory_area().

#define MPU_SETUP_ENTRY_INVALIDBASEADDR   1

Referenced by set_mpu_entry().

#define MPU_SETUP_ENTRY_INVALIDSIZE   2

Referenced by set_mpu_entry().

#define MPU_SETUP_ENTRY_OK   0

MPU entry set up function (set_mpu_entry) return codes.

Referenced by set_mpu_entry().

enum eRegionSize

Possible protected region sizes. Based on Table 5.1 in doc32002 "AVR32UC Technical Reference Manual Complete".

Enumerator
MPU_REGION_SIZE_LOWLIMIT_FORBIDDEN
MPU_REGION_SIZE_4KB
MPU_REGION_SIZE_8KB
MPU_REGION_SIZE_16KB
MPU_REGION_SIZE_32KB
MPU_REGION_SIZE_64KB
MPU_REGION_SIZE_128KB
MPU_REGION_SIZE_256KB
MPU_REGION_SIZE_512KB
MPU_REGION_SIZE_1MB
MPU_REGION_SIZE_2MB
MPU_REGION_SIZE_4MB
MPU_REGION_SIZE_8MB
MPU_REGION_SIZE_16MB
MPU_REGION_SIZE_32MB
MPU_REGION_SIZE_64MB
MPU_REGION_SIZE_128MB
MPU_REGION_SIZE_256MB
MPU_REGION_SIZE_512MB
MPU_REGION_SIZE_1GB
MPU_REGION_SIZE_2GB
MPU_REGION_SIZE_4GB
MPU_REGION_SIZE_HIGHLIMIT_FORBIDDEN

void disable_mpu

(

void

)

Disable the memory protection unit. MPU address checking is disabled, no exceptions will be generated by the MPU.

Control of the MPU control register MPUCR: disable MPUCR

References Set_system_register.

Referenced by handle_exception().

void disable_mpu_entry	(	unsigned int	region_number,
		unsigned int	register_select
	)

Disable a MPU entry

Parameters

region_number,:	MPU entry region number (0..7).
register_select,:	register A: '0' – B: '1'

References Set_system_register.

void enable_mpu

(

void

)

Enable the memory protection unit. MPU address checking is enabled.

Control of the MPU control register MPUCR: enable MPUCR

References Set_system_register.

Referenced by configure_memory_area().

bool mpu_convert_kbsize_to_eregionsize	(	eRegionSize *	peRegionSizeValue,
		U32	kBSizeValue
	)

Converts an input region size expressed in kBytes to the corresponding eRegionSize type value.

Parameters

kBSizeValue,:	input region size expressed in kBytes
peRegionSizeValue,:	output region size in the eRegionSize type

Returns

bool true if the conversion succeeded false if the conversion failed (the input is not a possible protected region size).

References clz, MPU_REGION_SIZE_HIGHLIMIT_FORBIDDEN, and MPU_REGION_SIZE_LOWLIMIT_FORBIDDEN.

Referenced by configure_memory_area().

void select_subregion	(	unsigned int	region_number,
		unsigned int	pattern_select
	)

Setup a Subregion

Parameters

region_number,:	MPU entry region number (0..7).
pattern_select,:	bit-field for the 16 subregions: register A: '0' – B: '1'

References Set_system_register.

Referenced by configure_memory_area().

void set_access_permissions	(	unsigned int	region_number,
		unsigned int	register_select,
		unsigned int	right_access
	)

Setup a register A and B

Parameters

region_number,:	MPU entry region number (0..7).
register_select,:	register A: '0' – B: '1'
right_access,:	R/W/X see doc32002.pdf (Table 5-3. Access permissions implied by the APn bits)

References Get_system_register, and Set_system_register.

Referenced by configure_memory_area().

char set_mpu_entry	(	const mpu_entry_t *	mpu_entry,
		unsigned int	region_number
	)

Setup a MPU entry

Parameters

mpu_entry,:	pointer to mpu_entry_t with the MPU settings (base address, size, validity, access permission) .
region_number,:	MPU entry region number (0..7).

Returns

int MPU_SETUP_ENTRY_OK if the setup succeeded MPU_SETUP_ENTRY_INVALIDBASEADDR if the setup failed because the input base address is not aligned to the size of the region. MPU_SETUP_ENTRY_INVALIDSIZE if the setup failed because the input size is not a power of 2 or is less than 4kB or is bigger than 4GB.

Setup a MPU entry

Parameters

mpu_entry,:	pointer to mpu_entry_t with the MPU settings (base address, size, validity).
region_number,:	MPU entry region number (0..7).

Returns

int MPU_SETUP_ENTRY_OK if the setup succeeded MPU_SETUP_ENTRY_INVALIDBASEADDR if the setup failed because the input base address is not aligned to the size of the region. MPU_SETUP_ENTRY_INVALIDSIZE if the setup failed because the input size is not one of the type eRegionSize.

References mpu_entry_t::addr, MPU_REGION_SIZE_HIGHLIMIT_FORBIDDEN, MPU_REGION_SIZE_LOWLIMIT_FORBIDDEN, MPU_SETUP_ENTRY_INVALIDBASEADDR, MPU_SETUP_ENTRY_INVALIDSIZE, MPU_SETUP_ENTRY_OK, Set_system_register, mpu_entry_t::size, Test_align, and mpu_entry_t::valid.

Referenced by configure_memory_area().