gddr_cal.c File Reference

#include "gddr_cal.h"
#include <errno.h>
#include <zephyr/device.h>
#include <zephyr/drivers/flash.h>
#include <zephyr/logging/log.h>
#include <zephyr/storage/flash_map.h>
#include <zephyr/sys/crc.h>
#include <zephyr/sys/util.h>

Include dependency graph for gddr_cal.c:

Functions
	LOG_MODULE_REGISTER (gddr_cal, CONFIG_TT_APP_LOG_LEVEL)
int	gddr_cal_read (gddr_cal_table_t *table)
	Read and validate the CA calibration table from flash.
int	gddr_cal_write (const gddr_cal_table_t *table)
	Write the CA calibration table to flash.

Function Documentation

gddr_cal_read()

int gddr_cal_read

(

gddr_cal_table_t *

table

)

Read and validate the CA calibration table from flash.

Reads both banks, prefers the one with the newer sequence number, and falls back to the other if it fails validation. Erased banks fail the magic check and are treated as absent, as are banks written by an older firmware whose table layout differed.

CONFIG_TT_BH_ARC_GDDR_CA_LATCH requires gddrcal_a and gddrcal_b in the devicetree; a build without those nodes is rejected at compile time.

Parameters

[out]

table

Destination table; only written on success.

Return values

0	on success.
-ENODEV	if the flash device is not ready.
-ENOENT	if neither bank holds a valid table.
-ENOSYS	if the latch Kconfig is off and the partitions are absent.

gddr_cal_write()

int gddr_cal_write

(

const gddr_cal_table_t *

table

)

Write the CA calibration table to flash.

Writes to whichever bank is not currently active, with a sequence number one greater than the active bank's, then reads the bank back and verifies it. The active bank is never erased, so a power loss at any point leaves the previous table intact and readable.

Parameters

[in]

table

Table to store.

Return values

0	on success, negative error code on failure.
-ENOSYS	if the latch Kconfig is off and the partitions are absent.

LOG_MODULE_REGISTER()

LOG_MODULE_REGISTER	(	gddr_cal	,
		CONFIG_TT_APP_LOG_LEVEL	)