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Diffstat (limited to 'src/drivers/spi/cbfs_spi.c')
-rw-r--r--src/drivers/spi/cbfs_spi.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/src/drivers/spi/cbfs_spi.c b/src/drivers/spi/cbfs_spi.c
new file mode 100644
index 0000000000..bbe9125dd5
--- /dev/null
+++ b/src/drivers/spi/cbfs_spi.c
@@ -0,0 +1,80 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2014 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.
+ */
+
+/*
+ * This file provides a common CBFS wrapper for SPI storage. SPI driver
+ * context is expanded with the buffer descriptor used to store data read from
+ * SPI.
+ */
+
+#include <boot_device.h>
+#include <spi_flash.h>
+#include <symbols.h>
+#include <cbmem.h>
+
+static struct spi_flash *spi_flash_info;
+
+static ssize_t spi_readat(const struct region_device *rd, void *b,
+ size_t offset, size_t size)
+{
+ if (spi_flash_info->read(spi_flash_info, offset, size, b))
+ return -1;
+ return size;
+}
+
+static const struct region_device_ops spi_ops = {
+ .mmap = mmap_helper_rdev_mmap,
+ .munmap = mmap_helper_rdev_munmap,
+ .readat = spi_readat,
+};
+
+static struct mmap_helper_region_device mdev =
+ MMAP_HELPER_REGION_INIT(&spi_ops, 0, CONFIG_ROM_SIZE);
+
+static void switch_to_postram_cache(int unused)
+{
+ /*
+ * Call boot_device_init() to ensure spi_flash is initialized before
+ * backing mdev with postram cache. This prevents the mdev backing from
+ * being overwritten if spi_flash was not accessed before dram was up.
+ */
+ boot_device_init();
+ if (_preram_cbfs_cache != _postram_cbfs_cache)
+ mmap_helper_device_init(&mdev, _postram_cbfs_cache,
+ _postram_cbfs_cache_size);
+}
+ROMSTAGE_CBMEM_INIT_HOOK(switch_to_postram_cache);
+
+void boot_device_init(void)
+{
+ int bus = CONFIG_BOOT_DEVICE_SPI_FLASH_BUS;
+ int cs = 0;
+
+ if (spi_flash_info != NULL)
+ return;
+
+ spi_flash_info = spi_flash_probe(bus, cs);
+
+ mmap_helper_device_init(&mdev, _cbfs_cache, _cbfs_cache_size);
+}
+
+/* Return the CBFS boot device. */
+const struct region_device *boot_device_ro(void)
+{
+ if (spi_flash_info == NULL)
+ return NULL;
+
+ return &mdev.rdev;
+}