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Diffstat (limited to 'drivers/char/tpm/eventlog/of.c')
-rw-r--r--drivers/char/tpm/eventlog/of.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/drivers/char/tpm/eventlog/of.c b/drivers/char/tpm/eventlog/of.c
new file mode 100644
index 000000000000..e1ec532298f0
--- /dev/null
+++ b/drivers/char/tpm/eventlog/of.c
@@ -0,0 +1,82 @@
+/*
+ * Copyright 2012 IBM Corporation
+ *
+ * Author: Ashley Lai <ashleydlai@gmail.com>
+ * Nayna Jain <nayna@linux.vnet.ibm.com>
+ *
+ * Maintained by: <tpmdd-devel@lists.sourceforge.net>
+ *
+ * Read the event log created by the firmware on PPC64
+ *
+ * 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 (at your option) any later version.
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/tpm_eventlog.h>
+
+#include "../tpm.h"
+
+int tpm_read_log_of(struct tpm_chip *chip)
+{
+ struct device_node *np;
+ const u32 *sizep;
+ const u64 *basep;
+ struct tpm_bios_log *log;
+ u32 size;
+ u64 base;
+
+ log = &chip->log;
+ if (chip->dev.parent && chip->dev.parent->of_node)
+ np = chip->dev.parent->of_node;
+ else
+ return -ENODEV;
+
+ if (of_property_read_bool(np, "powered-while-suspended"))
+ chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED;
+
+ sizep = of_get_property(np, "linux,sml-size", NULL);
+ basep = of_get_property(np, "linux,sml-base", NULL);
+ if (sizep == NULL && basep == NULL)
+ return -ENODEV;
+ if (sizep == NULL || basep == NULL)
+ return -EIO;
+
+ /*
+ * For both vtpm/tpm, firmware has log addr and log size in big
+ * endian format. But in case of vtpm, there is a method called
+ * sml-handover which is run during kernel init even before
+ * device tree is setup. This sml-handover function takes care
+ * of endianness and writes to sml-base and sml-size in little
+ * endian format. For this reason, vtpm doesn't need conversion
+ * but physical tpm needs the conversion.
+ */
+ if (of_property_match_string(np, "compatible", "IBM,vtpm") < 0) {
+ size = be32_to_cpup((__force __be32 *)sizep);
+ base = be64_to_cpup((__force __be64 *)basep);
+ } else {
+ size = *sizep;
+ base = *basep;
+ }
+
+ if (size == 0) {
+ dev_warn(&chip->dev, "%s: Event log area empty\n", __func__);
+ return -EIO;
+ }
+
+ log->bios_event_log = kmalloc(size, GFP_KERNEL);
+ if (!log->bios_event_log)
+ return -ENOMEM;
+
+ log->bios_event_log_end = log->bios_event_log + size;
+
+ memcpy(log->bios_event_log, __va(base), size);
+
+ if (chip->flags & TPM_CHIP_FLAG_TPM2)
+ return EFI_TCG2_EVENT_LOG_FORMAT_TCG_2;
+ return EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
+}