HSK Flash Facility implementation. More...

#include <Infineon/XC878.h>
#include "hsk_flash.h"
#include <string.h>
#include "../hsk_isr/hsk_isr.h"

Include dependency graph for hsk_flash.c:

Macros
#define	MOVCI .db 0xA5
	MOVC @(DPTR++),A instruction. More...

#define	DPL dpl
	DPTR low byte. More...

#define	DPH dph
	DPTR high byte. More...

#define	VAR_AT(type, name, addr) type __at(addr) name
	Create variable at a certain address, SDCC version. More...

#define	VAR_ASM(name) _##name
	Insert global variable address into inline assembler SDCC style. More...

#define	PAGE_RAM 2
	XC878-16FF code page that has the Boot ROM and XRAM mapped into it. More...

#define	PAGE_FLASH 0
	XC878-16FF code page that has the flash. More...

#define	ADDR_PFLASH 0x0000
	XC878-16FF start address of the P-Flash. More...

#define	LEN_PFLASH (60u << 10)
	XC878-16FF length of the P-Flash. More...

#define	BYTES_PAGE_PFLASH (1 << 9)
	XC878-16FF the number of bytes in a P-Flash page. More...

#define	BYTES_WORDLINE_PFLASH (1 << 6)
	XC878-16FF the number of bytes in a P-Flash wordline. More...

#define	ADDR_DFLASH 0xF000
	XC878-16FF start address of the D-Flash. More...

#define	LEN_DFLASH (4u << 10)
	XC878-16FF length of the D-Flash. More...

#define	BYTES_PAGE_DFLASH (1 << 6)
	XC878-16FF the number of bytes in a D-Flash page. More...

#define	BYTES_WORDLINE_DFLASH (1 << 5)
	XC878-16FF ld() of the number of bytes in a D-Flash wordline. More...

#define	ADDR_ROM 0xC000
	XC878-16FF start address of the Boot ROM. More...

#define	LEN_ROM (8u << 10)
	XC878-16FF length of the Boot ROM. More...

#define	ADDR_XRAM 0xF000
	XC878-16FF start address of the XRAM. More...

#define	LEN_XRAM (3u << 10)
	XC878-16FF length of the XRAM. More...

#define	BIT_PROG 0
	FCON/EECON Program Bit. More...

#define	BIT_ERASE 1
	FCON/EECON Erase Bit. More...

#define	BIT_MAS1 2
	FCON/EECON Mass Erase Bit. More...

#define	BIT_NVSTR 3
	FCON/EECON Non-Volatile Store Bit. More...

#define	BIT_YE 5
	FCON/EECON Y-Address Enable Bit. More...

#define	BIT_EEBSY 6
	EECON D-Flash Busy Bit. More...

#define	BIT_FTEN 5
	FCS Flash Timer Enable Bit. More...

#define	BIT_EEABORT 0
	FCS1 D-Flash Program/Erase Abort bit. More...

#define	BIT_OFVAL 0
	FTVAL Overflow Value bits. More...

#define	CNT_OFVAL 7
	OFVAL bit count. More...

#define	BIT_MODE 7
	FTVAL MODE bit. More...

#define	BIT_NMIFLASH 2
	NMICON Flash Timer NMI Enable bit. More...

#define	STATE_IDLE 0
	The state to use when nothing is to be done. More...

#define	STATE_REQUEST 1
	The state to use to kick off a write. More...

#define	STATE_DETECT 10
	The state that decides whether a delete or idle is appropriate. More...

#define	STATE_WRITE 20
	The state to use when starting to write to the D-Flash. More...

#define	STATE_DELETE 40
	The state to use when erasing D-Flash pages. More...

#define	STATE_RESET 60
	The state to use when mass erasing the D-Flash. More...

#define	FREE_LATEST 0
	The block indicated hsk_flash::latest is available for writing. More...

#define	FREE_BEHIND 1
	The block behind the block indicated by hsk_flash::latest is available for writing. More...

#define	FREE_NONE 2
	There is no block available for writing. More...

Functions
void	hsk_flash_isr_nmiflash (void)
	Flash delete/write state machine. More...

ubyte	hsk_flash_init (void *const ptr, const uword size, const ubyte version)
	Recovers a struct from a previous session and sets everything up for storage of changes. More...

bool	hsk_flash_write (void)
	Writes the current data to the D-Flash. More...

Variables
const ubyte	hsk_flash_dflash [(4u<< 10)]
	Bytewise access to the D-Flash area. More...

SFR	FCON = 0xD1
	P-Flash Control Register. More...

SFR	EECON = 0xD2
	D-Flash Control Register. More...

SFR	FCS = 0xD3
	Flash Control and Status Register. More...

SFR	FEAL = 0xD4
	Flash Error Address Register Low. More...

SFR	FEAH = 0xD5
	Flash Error Address Register High. More...

SFR16	FEALH = 0xD4
	Flash Error Address Register Low and High (16 bits). More...

SFR	FTVAL = 0xD6
	Flash Timer Value Register. More...

SFR	FCS1 = 0xDD
	Flash Control and Status Register 1. More...

struct {
ubyte * ptr
	The pointer to the data structure to persist. More...

uword size
	The size of the data structure to persist. More...

uword wrap
	The useable amount of D-Flash. More...

uword oldest
	The offset of the oldest data in the D-Flash. More...

uword latest
	The offset of the latest data in the D-Flash. More...

ubyte free
	This byte indicates where free space can be found in the D-Flash. More...

ubyte ident
	The prefix/postfix to identify the data structure in the flash. More...

ubyte state
	The current state of the flash ISR state machine. More...

}	hsk_flash
	Holds the persistence configuration. More...

volatile ubyte *	hsk_flash_flashDptr
	A pointer to the flash target address. More...

volatile ubyte *	hsk_flash_xdataDptr
	A pointer to the xdata src address. More...

Detailed Description

HSK Flash Facility implementation.

This file implements the flash management functions defined in hsk_flash.h.

Author: kami

Flash Registers

All registers are in the mapped register are, i.e. RMAP=1 must be set to access them.

Flash Timer

Non-blocking flash reading/writing is controlled by a dedicated flash timer. Timings, especially flash writing, are so critical that all the flash delete/write procedures are implemented in a single state machine within hsk_flash_isr_nmiflash(), which is called by a non-maskable interrupt upon timer overflow.

DPTR Byte Order

Due to the Byte Order differences between SDCC and C51, the DPL and DPH macros are used to adjust DPTR assignments in inline assembler.

Macro Definition Documentation

#define ADDR_DFLASH 0xF000

XC878-16FF start address of the D-Flash.

#define ADDR_PFLASH 0x0000

XC878-16FF start address of the P-Flash.

#define ADDR_ROM 0xC000

XC878-16FF start address of the Boot ROM.

#define ADDR_XRAM 0xF000

XC878-16FF start address of the XRAM.

#define BIT_EEABORT 0

FCS1 D-Flash Program/Erase Abort bit.

#define BIT_EEBSY 6

EECON D-Flash Busy Bit.

#define BIT_ERASE 1

FCON/EECON Erase Bit.

#define BIT_FTEN 5

FCS Flash Timer Enable Bit.

#define BIT_MAS1 2

FCON/EECON Mass Erase Bit.

#define BIT_MODE 7

FTVAL MODE bit.

Controls the flash timer speed.

Mode	Value	Effect
Program	0	1 count per (24MHz) clock cycle
Erase	1	1 count per $CCLK/2^{12}$ clock cycles

#define BIT_NMIFLASH 2

NMICON Flash Timer NMI Enable bit.

#define BIT_NVSTR 3

FCON/EECON Non-Volatile Store Bit.

#define BIT_OFVAL 0

FTVAL Overflow Value bits.

#define BIT_PROG 0

FCON/EECON Program Bit.

#define BIT_YE 5

FCON/EECON Y-Address Enable Bit.

#define BYTES_PAGE_DFLASH (1 << 6)

XC878-16FF the number of bytes in a D-Flash page.

#define BYTES_PAGE_PFLASH (1 << 9)

XC878-16FF the number of bytes in a P-Flash page.

#define BYTES_WORDLINE_DFLASH (1 << 5)

XC878-16FF ld() of the number of bytes in a D-Flash wordline.

#define BYTES_WORDLINE_PFLASH (1 << 6)

XC878-16FF the number of bytes in a P-Flash wordline.

#define CNT_OFVAL 7

OFVAL bit count.

#define DPH dph

DPTR high byte.

See Also: DPTR Byte Order

#define DPL dpl

DPTR low byte.

See Also: DPTR Byte Order

#define FREE_BEHIND 1

The block behind the block indicated by hsk_flash::latest is available for writing.

#define FREE_LATEST 0

The block indicated hsk_flash::latest is available for writing.

#define FREE_NONE 2

There is no block available for writing.

#define LEN_DFLASH (4u << 10)

XC878-16FF length of the D-Flash.

#define LEN_PFLASH (60u << 10)

XC878-16FF length of the P-Flash.

#define LEN_ROM (8u << 10)

XC878-16FF length of the Boot ROM.

#define LEN_XRAM (3u << 10)

XC878-16FF length of the XRAM.

#define MOVCI .db 0xA5

MOVC @(DPTR++),A instruction.

#define PAGE_FLASH 0

XC878-16FF code page that has the flash.

#define PAGE_RAM 2

XC878-16FF code page that has the Boot ROM and XRAM mapped into it.

#define STATE_DELETE 40

The state to use when erasing D-Flash pages.

#define STATE_DETECT 10

The state that decides whether a delete or idle is appropriate.

#define STATE_IDLE 0

The state to use when nothing is to be done.

#define STATE_REQUEST 1

The state to use to kick off a write.

#define STATE_RESET 60

The state to use when mass erasing the D-Flash.

#define STATE_WRITE 20

The state to use when starting to write to the D-Flash.

#define VAR_ASM ( name ) _##name

Insert global variable address into inline assembler SDCC style.

#define VAR_AT	(	type,
		name,
		addr
	)	type __at(addr) name

Create variable at a certain address, SDCC version.

Function Documentation

ubyte hsk_flash_init	(	void *const	ptr,
		const uword	size,
		const ubyte	version
	)

Recovers a struct from a previous session and sets everything up for storage of changes.

There are two modes of recovery. After a fresh boot the data can be recovered from flash, if previously stored there. After a simple reset the data can still be found in XRAM and recovery can be sped up.

If recovery fails entirely all members of the struct will be set to 0.

Parameters

version	Version number of the persisted data structure, used to prevent initilization with incompatible data
ptr	A pointer to the xdata struct/array to persist
size	The size of the data structure to persist

Return values

FLASH_PWR_FIRST	No valid data was recovered
FLASH_PWR_RESET	Continue operation after a reset
FLASH_PWR_ON	Data restore from the D-Flash succeeded

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void hsk_flash_isr_nmiflash ( void )

private

Flash delete/write state machine.

Every named state is the root of a state machine that performs a specific task.

See Also: Section 4.4 Flash Memory - Operating Modes from the XC8787 reference manual: XC878_um_v1_1.pdf

STATE_IDLE is a sleeping state that turns off the state machine. This state is a dead end, the state machine has to be reactivated externally to resume operation.

STATE_REQUEST implements the procedure called "Abort Operation" from the XC878 UM 1.1.

After completing the abort STATE_WRITE is entered.

STATE_DETECT checks whether there is a page that should be deleted.

It either goes into STATE_DELETE or STATE_IDLE.

STATE_WRITE implements the procedure called "Program Operation" from the XC878 UM 1.1.

The next address to write is expected in hsk_flash_flashDptr. The next address to read from XRAM is expected in hsk_flash_xdataDptr.

STATE_DELETE implements the procedure called "Erase Operation" from the XC878 UM 1.1.

STATE_RESET implements the procedure called "Mass Erase Operation" from the XC878 UM 1.1.

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bool hsk_flash_write ( void )

Writes the current data to the D-Flash.

Ongoing writes are interrupted. Ongoing deletes are interrupted unless there is insufficient space left to write the data.

Return values

1	The D-Flash write is on the way
0	Not enough free D-Flash space to write, try again later

Variable Documentation

SFR EECON = 0xD2

D-Flash Control Register.

SFR FCON = 0xD1

P-Flash Control Register.

SFR FCS = 0xD3

Flash Control and Status Register.

SFR FCS1 = 0xDD

Flash Control and Status Register 1.

SFR FEAH = 0xD5

Flash Error Address Register High.

SFR FEAL = 0xD4

Flash Error Address Register Low.

SFR16 FEALH = 0xD4

Flash Error Address Register Low and High (16 bits).

ubyte free

This byte indicates where free space can be found in the D-Flash.

Available values are:

SFR FTVAL = 0xD6

Flash Timer Value Register.

hsk_flash

Holds the persistence configuration.

const ubyte hsk_flash_dflash[(4u<< 10)]

Bytewise access to the D-Flash area.

volatile ubyte* hsk_flash_flashDptr

A pointer to the flash target address.

Not in a struct for easier inline assembler access.

volatile ubyte* hsk_flash_xdataDptr

A pointer to the xdata src address.

Not in a struct for easier inline assembler access.

ubyte ident

The prefix/postfix to identify the data structure in the flash.

It consist of the last 6 bits of the version and two alternating bits to make sure the value can neither become 0x00 nor 0xff.

Pre-/postfixing the ident ensures that the data was completely written.

uword latest

The offset of the latest data in the D-Flash.

uword oldest

The offset of the oldest data in the D-Flash.

ubyte* ptr

The pointer to the data structure to persist.

uword size

The size of the data structure to persist.

ubyte state

The current state of the flash ISR state machine.

uword wrap

The useable amount of D-Flash.

Macros

Functions

Variables