linux-zen-server/drivers/char/tpm/eventlog/of.c

109 lines
2.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* 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
*/
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_reserved_mem.h>
#include <linux/tpm_eventlog.h>
#include "../tpm.h"
#include "common.h"
static int tpm_read_log_memory_region(struct tpm_chip *chip)
{
struct device_node *node;
struct resource res;
int rc;
node = of_parse_phandle(chip->dev.parent->of_node, "memory-region", 0);
if (!node)
return -ENODEV;
rc = of_address_to_resource(node, 0, &res);
of_node_put(node);
if (rc)
return rc;
chip->log.bios_event_log = devm_memremap(&chip->dev, res.start, resource_size(&res),
MEMREMAP_WB);
if (IS_ERR(chip->log.bios_event_log))
return -ENOMEM;
chip->log.bios_event_log_end = chip->log.bios_event_log + resource_size(&res);
return chip->flags & TPM_CHIP_FLAG_TPM2 ? EFI_TCG2_EVENT_LOG_FORMAT_TCG_2 :
EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
}
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 tpm_read_log_memory_region(chip);
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 &&
of_property_match_string(np, "compatible", "IBM,vtpm20") < 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 = devm_kmemdup(&chip->dev, __va(base), size, GFP_KERNEL);
if (!log->bios_event_log)
return -ENOMEM;
log->bios_event_log_end = log->bios_event_log + 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;
}