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Diffstat (limited to 'src/soc/intel/baytrail/nvm.c')
-rw-r--r--src/soc/intel/baytrail/nvm.c83
1 files changed, 83 insertions, 0 deletions
diff --git a/src/soc/intel/baytrail/nvm.c b/src/soc/intel/baytrail/nvm.c
new file mode 100644
index 0000000000..dccc8014dc
--- /dev/null
+++ b/src/soc/intel/baytrail/nvm.c
@@ -0,0 +1,83 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2013 Google Inc.
+ *
+ * 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; version 2 of the License.
+ *
+ * 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 St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+#include <stddef.h>
+#include <console/console.h>
+#include <string.h>
+#include <spi-generic.h>
+#include <spi_flash.h>
+#include <baytrail/nvm.h>
+
+/* This module assumes the flash is memory mapped just below 4GiB in the
+ * address space for reading. Also this module assumes an area it erased
+ * when all bytes read as all 0xff's. */
+
+static struct spi_flash *flash;
+
+static int nvm_init(void)
+{
+ if (flash != NULL)
+ return 0;
+
+ spi_init();
+ flash = spi_flash_probe(0, 0, 1000000, SPI_MODE_3);
+ if (!flash) {
+ printk(BIOS_DEBUG, "Could not find SPI device\n");
+ return -1;
+ }
+
+ return 0;
+}
+
+/* Convert memory mapped pointer to flash offset. */
+static inline uint32_t to_flash_offset(void *p)
+{
+ return CONFIG_ROM_SIZE + (uintptr_t)p;
+}
+
+int nvm_is_erased(const void *start, size_t size)
+{
+ const char *cur = start;
+
+ while (size > 0) {
+ if (*cur != 0xff)
+ return 0;
+ cur++;
+ size--;
+ }
+ return 1;
+}
+
+int nvm_erase(void *start, size_t size)
+{
+ if (nvm_init() < 0)
+ return -1;
+ flash->erase(flash, to_flash_offset(start), size);
+ return 0;
+}
+
+/* Write data to NVM. Returns 0 on success < 0 on error. */
+int nvm_write(void *start, const void *data, size_t size)
+{
+ if (nvm_init() < 0)
+ return -1;
+ flash->write(flash, to_flash_offset(start), size, data);
+ return 0;
+}