nvs.c File Reference

Non-volatile storage. More...

#include <stdint.h>
#include <string.h>
#include <errno.h>
#include <assert.h>
#include <gpxe/nvs.h>

Go to the source code of this file.

Functions
	FILE_LICENCE (GPL2_OR_LATER)
int	nvs_read (struct nvs_device *nvs, unsigned int address, void *data, size_t len)
	Read from non-volatile storage device.
static int	nvs_verify (struct nvs_device *nvs, unsigned int address, const void *data, size_t len)
	Verify content of non-volatile storage device.
int	nvs_write (struct nvs_device *nvs, unsigned int address, const void *data, size_t len)
	Write to non-volatile storage device.

---

Detailed Description

Non-volatile storage.

Definition in file nvs.c.

---

Function Documentation

FILE_LICENCE

(

GPL2_OR_LATER

)

int nvs_read	(	struct nvs_device *	nvs,
		unsigned int	address,
		void *	data,
		size_t	len
	)

Read from non-volatile storage device.

Parameters:

	nvs	NVS device
	address	Address from which to read
	data	Data buffer
	len	Length of data buffer

Return values:

rc

Return status code

Definition at line 42 of file nvs.c.

References assert, nvs_device::block_size, nvs_device::read, and nvs_device::word_len_log2.

Referenced by a3c90x_internal_ReadEepromContents(), falcon_probe_nvram(), ifec_pci_probe(), natsemi_probe(), nvo_load(), nvs_verify(), rtl818x_probe(), and rtl_probe().

                                        {
        size_t frag_len;
        int rc;

        /* We don't even attempt to handle buffer lengths that aren't
         * an integral number of words.
         */
        assert ( ( len & ( ( 1 << nvs->word_len_log2 ) - 1 ) ) == 0 );

        while ( len ) {

                /* Calculate space remaining up to next block boundary */
                frag_len = ( ( nvs->block_size -
                               ( address & ( nvs->block_size - 1 ) ) )
                             << nvs->word_len_log2 );

                /* Limit to space remaining in buffer */
                if ( frag_len > len )
                        frag_len = len;

                /* Read this portion of the buffer from the device */
                if ( ( rc = nvs->read ( nvs, address, data, frag_len ) ) != 0 )
                        return rc;

                /* Update parameters */
                data += frag_len;
                address += ( frag_len >> nvs->word_len_log2 );
                len -= frag_len;
        }

        return 0;
}

static int nvs_verify	(	struct nvs_device *	nvs,
		unsigned int	address,
		const void *	data,
		size_t	len
	)			[static]

Verify content of non-volatile storage device.

Parameters:

	nvs	NVS device
	address	Address from which to read
	data	Data to compare against
	len	Length of data buffer

Return values:

rc

Return status code

Definition at line 85 of file nvs.c.

References DBG, EIO, memcmp(), and nvs_read().

Referenced by nvs_write().

                                                       {
        uint8_t read_data[len];
        int rc;

        /* Read data into temporary buffer */
        if ( ( rc = nvs_read ( nvs, address, read_data, len ) ) != 0 )
                return rc;

        /* Compare data */
        if ( memcmp ( data, read_data, len ) != 0 ) {
                DBG ( "NVS %p verification failed at %#04x+%zd\n",
                      nvs, address, len );
                return -EIO;
        }

        return 0;
}

int nvs_write	(	struct nvs_device *	nvs,
		unsigned int	address,
		const void *	data,
		size_t	len
	)

Write to non-volatile storage device.

Parameters:

	nvs	NVS device
	address	Address to which to write
	data	Data buffer
	len	Length of data buffer

Return values:

rc

Return status code

Definition at line 113 of file nvs.c.

References assert, nvs_device::block_size, nvs_verify(), nvs_device::word_len_log2, and nvs_device::write.

Referenced by nvo_save().

                                               {
        size_t frag_len;
        int rc;

        /* We don't even attempt to handle buffer lengths that aren't
         * an integral number of words.
         */
        assert ( ( len & ( ( 1 << nvs->word_len_log2 ) - 1 ) ) == 0 );

        while ( len ) {

                /* Calculate space remaining up to next block boundary */
                frag_len = ( ( nvs->block_size -
                               ( address & ( nvs->block_size - 1 ) ) )
                             << nvs->word_len_log2 );

                /* Limit to space remaining in buffer */
                if ( frag_len > len )
                        frag_len = len;

                /* Write this portion of the buffer to the device */
                if ( ( rc = nvs->write ( nvs, address, data, frag_len ) ) != 0)
                        return rc;

                /* Read back and verify data */
                if ( ( rc = nvs_verify ( nvs, address, data, frag_len ) ) != 0)
                        return rc;

                /* Update parameters */
                data += frag_len;
                address += ( frag_len >> nvs->word_len_log2 );
                len -= frag_len;
        }

        return 0;
}