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Diffstat (limited to 'qemu/roms/ipxe/src/drivers/nvs/nvs.c')
-rw-r--r--qemu/roms/ipxe/src/drivers/nvs/nvs.c166
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;
+}