[PATCH v2 4/4] tpm: Only enable supported irqs

From: Lino Sanfilippo
Date: Sun Apr 25 2021 - 19:49:14 EST


Do not set interrupts which are not supported by the hardware. Instead use
the information from the capability query and activate only the reported
interrupts.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@xxxxxx>
---
drivers/char/tpm/tpm_tis_core.c | 68 ++++++++++++++++++++++-------------------
drivers/char/tpm/tpm_tis_core.h | 1 +
2 files changed, 38 insertions(+), 31 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index e8ab218..7b00161 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -980,13 +980,47 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
if (rc)
goto out_err;

+ /* Figure out the capabilities */
+ rc = tpm_tis_read32(priv, TPM_INTF_CAPS(priv->locality), &intfcaps);
+ if (rc < 0)
+ goto out_err;
+
+ dev_dbg(dev, "TPM interface capabilities (0x%x):\n",
+ intfcaps);
+ if (intfcaps & TPM_INTF_BURST_COUNT_STATIC)
+ dev_dbg(dev, "\tBurst Count Static\n");
+ if (intfcaps & TPM_INTF_CMD_READY_INT) {
+ priv->supported_irqs |= TPM_INTF_CMD_READY_INT;
+ dev_dbg(dev, "\tCommand Ready Int Support\n");
+ }
+ if (intfcaps & TPM_INTF_INT_EDGE_FALLING)
+ dev_dbg(dev, "\tInterrupt Edge Falling\n");
+ if (intfcaps & TPM_INTF_INT_EDGE_RISING)
+ dev_dbg(dev, "\tInterrupt Edge Rising\n");
+ if (intfcaps & TPM_INTF_INT_LEVEL_LOW)
+ dev_dbg(dev, "\tInterrupt Level Low\n");
+ if (intfcaps & TPM_INTF_INT_LEVEL_HIGH)
+ dev_dbg(dev, "\tInterrupt Level High\n");
+ if (intfcaps & TPM_INTF_LOCALITY_CHANGE_INT) {
+ priv->supported_irqs |= TPM_INTF_LOCALITY_CHANGE_INT;
+ dev_dbg(dev, "\tLocality Change Int Support\n");
+ }
+ if (intfcaps & TPM_INTF_STS_VALID_INT) {
+ priv->supported_irqs |= TPM_INTF_STS_VALID_INT;
+ dev_dbg(dev, "\tSts Valid Int Support\n");
+ }
+ if (intfcaps & TPM_INTF_DATA_AVAIL_INT) {
+ priv->supported_irqs |= TPM_INTF_DATA_AVAIL_INT;
+ dev_dbg(dev, "\tData Avail Int Support\n");
+ }
+
/* Take control of the TPM's interrupt hardware and shut it off */
rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
if (rc < 0)
goto out_err;

- intmask |= TPM_INTF_CMD_READY_INT | TPM_INTF_LOCALITY_CHANGE_INT |
- TPM_INTF_DATA_AVAIL_INT | TPM_INTF_STS_VALID_INT;
+ intmask |= priv->supported_irqs;
+
intmask &= ~TPM_GLOBAL_INT_ENABLE;
tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);

@@ -1015,32 +1049,6 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
goto out_err;
}

- /* Figure out the capabilities */
- rc = tpm_tis_read32(priv, TPM_INTF_CAPS(priv->locality), &intfcaps);
- if (rc < 0)
- goto out_err;
-
- dev_dbg(dev, "TPM interface capabilities (0x%x):\n",
- intfcaps);
- if (intfcaps & TPM_INTF_BURST_COUNT_STATIC)
- dev_dbg(dev, "\tBurst Count Static\n");
- if (intfcaps & TPM_INTF_CMD_READY_INT)
- dev_dbg(dev, "\tCommand Ready Int Support\n");
- if (intfcaps & TPM_INTF_INT_EDGE_FALLING)
- dev_dbg(dev, "\tInterrupt Edge Falling\n");
- if (intfcaps & TPM_INTF_INT_EDGE_RISING)
- dev_dbg(dev, "\tInterrupt Edge Rising\n");
- if (intfcaps & TPM_INTF_INT_LEVEL_LOW)
- dev_dbg(dev, "\tInterrupt Level Low\n");
- if (intfcaps & TPM_INTF_INT_LEVEL_HIGH)
- dev_dbg(dev, "\tInterrupt Level High\n");
- if (intfcaps & TPM_INTF_LOCALITY_CHANGE_INT)
- dev_dbg(dev, "\tLocality Change Int Support\n");
- if (intfcaps & TPM_INTF_STS_VALID_INT)
- dev_dbg(dev, "\tSts Valid Int Support\n");
- if (intfcaps & TPM_INTF_DATA_AVAIL_INT)
- dev_dbg(dev, "\tData Avail Int Support\n");
-
/* INTERRUPT Setup */
init_waitqueue_head(&priv->read_queue);
init_waitqueue_head(&priv->int_queue);
@@ -1110,9 +1118,7 @@ static void tpm_tis_reenable_interrupts(struct tpm_chip *chip)
if (rc < 0)
goto out;

- intmask |= TPM_INTF_CMD_READY_INT
- | TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_DATA_AVAIL_INT
- | TPM_INTF_STS_VALID_INT | TPM_GLOBAL_INT_ENABLE;
+ intmask |= chip->supported_irqs | TPM_GLOBAL_INT_ENABLE;

tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);

diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h
index dc5f92b..8ff62213 100644
--- a/drivers/char/tpm/tpm_tis_core.h
+++ b/drivers/char/tpm/tpm_tis_core.h
@@ -89,6 +89,7 @@ struct tpm_tis_data {
u16 manufacturer_id;
int locality;
int irq;
+ unsigned int supported_irqs;
unsigned int flags;
void __iomem *ilb_base_addr;
u16 clkrun_enabled;
--
2.7.4