diff options
Diffstat (limited to 'qemu/roms/ipxe/src/drivers/nvs/nvs.c')
-rw-r--r-- | qemu/roms/ipxe/src/drivers/nvs/nvs.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/drivers/nvs/nvs.c b/qemu/roms/ipxe/src/drivers/nvs/nvs.c new file mode 100644 index 000000000..ccb2145bd --- /dev/null +++ b/qemu/roms/ipxe/src/drivers/nvs/nvs.c @@ -0,0 +1,166 @@ +/* + * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +FILE_LICENCE ( GPL2_OR_LATER ); + +#include <stdint.h> +#include <string.h> +#include <errno.h> +#include <assert.h> +#include <ipxe/nvs.h> + +/** @file + * + * Non-volatile storage + * + */ + +/** + * Calculate length up to next block boundary + * + * @v nvs NVS device + * @v address Starting address + * @v max_len Maximum length + * @ret len Length to use, stopping at block boundaries + */ +static size_t nvs_frag_len ( struct nvs_device *nvs, unsigned int address, + size_t max_len ) { + size_t frag_len; + + /* If there are no block boundaries, return the maximum length */ + if ( ! nvs->block_size ) + return max_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 maximum length */ + if ( max_len < frag_len ) + return max_len; + + return frag_len; +} + +/** + * Read from non-volatile storage device + * + * @v nvs NVS device + * @v address Address from which to read + * @v data Data buffer + * @v len Length of data buffer + * @ret rc Return status code + */ +int nvs_read ( struct nvs_device *nvs, unsigned int address, + void *data, size_t len ) { + 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 length to read, stopping at block boundaries */ + frag_len = nvs_frag_len ( nvs, address, 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; +} + +/** + * Verify content of non-volatile storage device + * + * @v nvs NVS device + * @v address Address from which to read + * @v data Data to compare against + * @v len Length of data buffer + * @ret rc Return status code + */ +static int nvs_verify ( struct nvs_device *nvs, unsigned int address, + const void *data, size_t len ) { + 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; +} + +/** + * Write to non-volatile storage device + * + * @v nvs NVS device + * @v address Address to which to write + * @v data Data buffer + * @v len Length of data buffer + * @ret rc Return status code + */ +int nvs_write ( struct nvs_device *nvs, unsigned int address, + const void *data, size_t len ) { + 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 length to write, stopping at block boundaries */ + frag_len = nvs_frag_len ( nvs, address, 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; +} |