tpm/tpm_crb: Access locality for only CRB_START method

PATCH Superseded Jiandi An 2 participants 2 messages Aug 7, 2017 – Aug 8, 2017 TPM device driver

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Jiandi An

author

2017-08-07 02:54 UTC #0 lore raw

PATCH 1/1 tpm/tpm_crb: Access locality for only CRB_START method

For ARM64, the locality is handled by Trust Zone in FW. The layout does not have crb_regs_head. It is hitting the following line.
dev_warn(dev, FW_BUG "Bad ACPI memory layout");

Current code excludes CRB_FL_ACPI_START and when CRB_FL_CRB_SMC_START is added around the same time locality support is added, it should also be excluded. Change the if condition to be only for CRB_FL_CRB_START.

For goIdle and cmdReady where code was excluding CRB_FL_ACPI_START only (do nothing for ACPI start method), CRB_FL_CRB_SMC_START was also excluded as ARM64 SMC start method does not have TPM_CRB_CTRL_REQ.
Change the if condition to be only for CRB_FL_CRB_START in crb_go_idle() and crb_cmd_ready().

Signed-off-by Jiandi An <[email protected]>

---
 drivers/char/tpm/tpm_crb.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

drivers/char/tpm/tpm_crb.c +6 -6

index 8f0a98d..d583c50 100644
@@ -128,14 +128,14 @@ struct tpm2_crb_smc {
  * Anyhow, we do not wait here as a consequent CMD_READY request
  * will be handled correctly even if idle was not completed.
  *
- * The function does nothing for devices with ACPI-start method.
+ * The function does nothing for devices with ACPI-start method
+ * and SMC-start method.
  *
  * Return: 0 always
  */
 static int __maybe_unused crb_go_idle(struct device *dev, struct crb_priv *priv)
 {
-	if ((priv->flags & CRB_FL_ACPI_START) ||
-	    (priv->flags & CRB_FL_CRB_SMC_START))
+	if (!(priv->flags & CRB_FL_CRB_START))
 		return 0;
 
 	iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->regs_t->ctrl_req);

@@ -174,14 +174,14 @@ static bool crb_wait_for_reg_32(u32 __iomem *reg, u32 mask, u32 value,
  * The device should respond within TIMEOUT_C.
  *
  * The function does nothing for devices with ACPI-start method
+ * and SMC-start method.
  *
  * Return: 0 on success -ETIME on timeout;
  */
 static int __maybe_unused crb_cmd_ready(struct device *dev,
 					struct crb_priv *priv)
 {
-	if ((priv->flags & CRB_FL_ACPI_START) ||
-	    (priv->flags & CRB_FL_CRB_SMC_START))
+	if (!(priv->flags & CRB_FL_CRB_START))
 		return 0;
 
 	iowrite32(CRB_CTRL_REQ_CMD_READY, &priv->regs_t->ctrl_req);

@@ -458,7 +458,7 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
 	 * the control area, as one nice sane region except for some older
 	 * stuff that puts the control area outside the ACPI IO region.
 	 */
-	if (!(priv->flags & CRB_FL_ACPI_START)) {
+	if (priv->flags & CRB_FL_CRB_START) {
 		if (buf->control_address == io_res.start +
 		    sizeof(*priv->regs_h))
 			priv->regs_h = priv->iobase;

Signature · 3 lines

Jiandi An
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

Jason Gunthorpe

2017-08-08 22:36 UTC #1 lore raw

drivers/char/tpm/tpm_crb.c struct tpm2_crb_smc { · line 138

Quoted 5 lines · Jiandi An

static int __maybe_unused crb_go_idle(struct device *dev, struct crb_priv *priv) {
drivers/char/tpm/tpm_crb.c +1 -2
-	if ((priv->flags & CRB_FL_ACPI_START) ||
-	    (priv->flags & CRB_FL_CRB_SMC_START))
+	if (!(priv->flags & CRB_FL_CRB_START))

I think it would be better to have these list the cases where go_idle is known to be required. Less brittle that way..

if ((priv->flags & (CRB_FL_ACPI_START | CRB_FL_CRB_START)) == 0)
return 0

drivers/char/tpm/tpm_crb.c static int crb_map_io(struct acpi_device *device, struct crb_priv *priv, · line 461

Quoted 2 lines

drivers/char/tpm/tpm_crb.c +1 -1

-	if (!(priv->flags & CRB_FL_ACPI_START)) {
+	if (priv->flags & CRB_FL_CRB_START) {

Eg like this now makes more sense, assumming CRB_START is the right test :)

Jason