Hi Jarkko,
Thanks for the review.
On Sun, Oct 25, 2026 at 10:55:20PM +0200, Jarkko Sakkinen wrote:
> On Mon, Oct 26, 2026 at 01:48:54AM +0530, Arun Menon wrote:
> > From: Arun Menon <[email protected]>
> >
> > The current implementation handles different platform start methods
> > (ACPI, ARM SMC, and ARM FFA) directly within crb_send().
> > Move this logic into a new helper function, tpm_crb_start(). This is a
> > pure refactor with no functional changes intended.
> >
> > Signed-off-by: Arun Menon <[email protected]>
> > Reviewed-by: Jarkko Sakkinen <[email protected]>
> > ---
> > drivers/char/tpm/tpm_crb.c | 50 ++++++++++++++++++++------------------
> > 1 file changed, 27 insertions(+), 23 deletions(-)
> >
> > diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
> > index d76f9e30f036..9a2f512b4ae3 100644
> > --- a/drivers/char/tpm/tpm_crb.c
> > +++ b/drivers/char/tpm/tpm_crb.c
> > @@ -446,6 +446,32 @@ static int tpm_crb_smc_start(struct device *dev,
> > unsigned long func_id)
> > }
> > #endif
> >
> > +static int tpm_crb_start(struct tpm_chip *chip)
> > +{
> > + struct crb_priv *priv = dev_get_drvdata(&chip->dev);
> > + int rc = 0;
>
> After declarations thre should be empty line. checkpatch.pl should
> complain about this.
>
> > + /* The reason for the extra quirk is that the PTT in 4th Gen Core CPUs
>
> I probably did not spot this last time but:
>
> /*
> * ...
>
> https://docs.kernel.org/process/coding-style.html
I will amend the commit. Thanks.
>
> > + * report only ACPI start but in practice seems to require both
> > + * CRB start, hence invoking CRB start method if hid == MSFT0101.
> > + */
> > + if (priv->sm == ACPI_TPM2_COMMAND_BUFFER ||
> > + priv->sm == ACPI_TPM2_MEMORY_MAPPED ||
> > + !strcmp(priv->hid, "MSFT0101"))
> > + iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
> > + if (priv->sm == ACPI_TPM2_START_METHOD ||
> > + priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)
> > + rc = crb_do_acpi_start(chip);
> > + if (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) {
> > + iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
> > + rc = tpm_crb_smc_start(&chip->dev, priv->smc_func_id);
> > + }
> > + if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
> > + iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
> > + rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_COMMAND,
> > chip->locality);
> > + }
> > + return rc;
> > +}
> > +
> > static int crb_send(struct tpm_chip *chip, u8 *buf, size_t bufsiz, size_t
> > len)
> > {
> > struct crb_priv *priv = dev_get_drvdata(&chip->dev);
> > @@ -471,29 +497,7 @@ static int crb_send(struct tpm_chip *chip, u8 *buf,
> > size_t bufsiz, size_t len)
> > /* Make sure that cmd is populated before issuing start. */
> > wmb();
> >
> > - /* The reason for the extra quirk is that the PTT in 4th Gen Core CPUs
> > - * report only ACPI start but in practice seems to require both
> > - * CRB start, hence invoking CRB start method if hid == MSFT0101.
> > - */
> > - if (priv->sm == ACPI_TPM2_COMMAND_BUFFER ||
> > - priv->sm == ACPI_TPM2_MEMORY_MAPPED ||
> > - !strcmp(priv->hid, "MSFT0101"))
> > - iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
> > -
> > - if (priv->sm == ACPI_TPM2_START_METHOD ||
> > - priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)
> > - rc = crb_do_acpi_start(chip);
> > -
> > - if (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) {
> > - iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
> > - rc = tpm_crb_smc_start(&chip->dev, priv->smc_func_id);
> > - }
> > -
> > - if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
> > - iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
> > - rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_COMMAND,
> > chip->locality);
> > - }
> > -
> > + rc = tpm_crb_start(chip);
> > if (rc)
> > return rc;
> >
> > --
> > 2.54.0
> >
>
> Br, Jarkko
>
Regards,
Arun Menon
