The current implementation handles different platform start methods
(ACPI, ARM SMC, and ARM FFA) directly within crb_send(), but it is
limited to triggering the CRB_START_INVOKE bit.
To support cmd/rsp chunking, the driver must be able to send other
control bits, like CRB_START_NEXT_CHUNK, using these same
platform-specific paths.
By moving this logic into a new helper function, crb_trigger_tpm(),
the driver can now send any required control bit across all supported
platforms. This prepares the driver for the upcoming chunking support.
No functional change is intended.
Signed-off-by: Arun Menon <armenon@redhat.com>
---
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 67c0061d4cab7..922bcf7a69ad5 100644
--- a/drivers/char/tpm/tpm_crb.c
+++ b/drivers/char/tpm/tpm_crb.c
@@ -445,6 +445,32 @@ static int tpm_crb_smc_start(struct device *dev, unsigned long func_id)
}
#endif
+static int crb_trigger_tpm(struct tpm_chip *chip, u32 start_cmd)
+{
+ struct crb_priv *priv = dev_get_drvdata(&chip->dev);
+ int rc = 0;
+ /* 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(start_cmd, &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(start_cmd, &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(start_cmd, &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);
@@ -470,29 +496,7 @@ 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 = crb_trigger_tpm(chip, CRB_START_INVOKE);
if (rc)
return rc;
--
2.53.0