On Sat, Nov 26, 2016 at 07:45:38AM -0500, Nayna Jain wrote:
> Physical TPMs use Open Firmware Device Tree bindings that are similar
> to the IBM Power virtual TPM to support event log. However, these
> properties store the values in different endianness for Physical
> and Virtual TPM.
>
> This patch fixes the endianness issue by doing appropriate conversion
> based on Physical or Virtual TPM.
>
> Signed-off-by: Nayna Jain <na...@linux.vnet.ibm.com>
> ---
> drivers/char/tpm/tpm_of.c | 27 +++++++++++++++++++++++----
> 1 file changed, 23 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm_of.c b/drivers/char/tpm/tpm_of.c
> index 7dee42d7..4b0d5e6 100644
> --- a/drivers/char/tpm/tpm_of.c
> +++ b/drivers/char/tpm/tpm_of.c
> @@ -27,6 +27,8 @@ int tpm_read_log_of(struct tpm_chip *chip)
> const u32 *sizep;
> const u64 *basep;
> struct tpm_bios_log *log;
> + u32 log_size;
> + u64 log_base;
Maybe just base and size?
>
> log = &chip->log;
> if (chip->dev.parent && chip->dev.parent->of_node)
> @@ -41,18 +43,35 @@ int tpm_read_log_of(struct tpm_chip *chip)
> if (sizep == NULL || basep == NULL)
> return -EIO;
>
> - if (*sizep == 0) {
> + /*
> + * 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) {
> + log_size = be32_to_cpup(sizep);
> + log_base = be64_to_cpup(basep);
> + } else {
> + log_size = *sizep;
> + log_base = *basep;
> + }
> +
> + if (log_size == 0) {
> dev_warn(&chip->dev, "%s: Event log area empty\n", __func__);
> return -EIO;
> }
>
> - log->bios_event_log = kmalloc(*sizep, GFP_KERNEL);
> + log->bios_event_log = kmalloc(log_size, GFP_KERNEL);
> if (!log->bios_event_log)
> return -ENOMEM;
>
> - log->bios_event_log_end = log->bios_event_log + *sizep;
> + log->bios_event_log_end = log->bios_event_log + log_size;
>
> - memcpy(log->bios_event_log, __va(*basep), *sizep);
> + memcpy(chip->log.bios_event_log, __va(log_base), log_size);
Why did you change the first parameter?
>
> return 0;
> }
> --
> 2.5.0
>
/Jarkko
