All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH v9 00/12] TPM IRQ fixes
@ 2022-11-10 15:25 Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 01/12] tpm, tpm_tis: Avoid cache incoherency in test for interrupts Lino Sanfilippo
                   ` (11 more replies)
  0 siblings, 12 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

This series enables IRQ support for the TPM TIS core. For this reason a
number of bugfixes around the interrupt handling are required (patches 1 to
4).

Patch 5 takes into account that according to the TPM Interface
Specification stsValid and commandRead interrupts might not be supported
by the hardware. For this reason the supported interrupts are first queried
and stored. Then wait_for_tpm_stat() is adjusted to not wait for status
changes that are not reported by interrupts.

Patch 6 moves the interrupt flag checks into an own function as suggested
by Jarkko.

Patch 7 Removes the possibility that tpm_tis_data->locality can be changed
at driver runtime so this variable can be read without the need to protect
it against concurrent modification. 

Patch 8 addresses the issue with concurrent locality handling:
Since the interrupt handler writes the interrupt status registers it needs
to hold the locality. However it runs concurrently to the thread which
triggered the interrupt (e.g. by reading or writing data to the TPM). So
it must take care when claiming and releasing the locality itself,
because it may race with the concurrent running thread which also claims
and releases the locality.
To avoid that both interrupt and concurrent running thread interfere with
each other a locality counter is used which guarantees that at any time
the locality is held as long as it is required by one of both execution
paths.

Patch 9 implements the request of a threaded interrupt handler. This is
needed since SPI uses a mutex for data transmission and since we access the
interrupt status register via SPI in the irq handler we need a sleepable
context.

Patch 10 makes sure that writes to the interrupt register are effective if
done in the interrupt handler.

Patch 11 makes sure that writes to the interrupt and INTERRUPT_VECTOR
and INTERRUPT_ENABLE registers are effective by holding the locality.

Patch 12 enables the test for interrupts by setting the required flag
before the test is executed.

Changes in v9:
- add a fix for an issue when interrupts are reenabled on resume (PATCH 11)
- improve the commit message for patch 8 as requested by Jarkko
- improved functions naming
- changed patch 12 (tpm, tpm_tis: Request threaded interrupt handler) to
  not delete the TPM_CHIP_FLAG_IRQ flag any more when tpm2_get_tpm_pt()
  fails. Due to this change the 'Tested-by' tag from Michael and the
  'Reviewed-by:' tag from Jarko has been removed

Changes in v8:
- tpm_tis_data->locality is not changed at runtime any more so that it can
be read without any protection against concurrent modification.
- add missing brackets as pointed out by Jason Andryuk

Changes in v7:
- moved interrupt flag checks into an own function as suggested by Jarkko
- added "Tested-by" tags for Tests from Michael Niewöhner
- fixed one comment

Changes in v6:
- set TPM_TIS_IRQ_TESTED in flag member of the tpm_tis_data struct instead
in an own bitfield 
- improve commit messages
- use int_mask instead of irqs_in_use as variable name
- use sts_mask instead of active_irqs as variable name
- squash patch 5 and 6
- prefix functions with tpm_tis_
- remove "fixes" tag

Changes in v5:
- improve commit message of patch 1 as requested by Jarko
- drop patch that makes locality handling simpler by only claiming it at
  driver startup and releasing it at driver shutdown (requested by Jarko)
- drop patch that moves the interrupt test from tpm_tis_send()
  to tmp_tis_probe_irq_single() as requested by Jarko
- add patch to make locality handling threadsafe so that it can also be
  done by the irq handler
- separate logical changes into own patches
- always request threaded interrupt handler

Changes in v4:
- only request threaded irq in case of SPI as requested by Jarko.
- reimplement patch 2 to limit locality handling changes to the TIS core.
- separate fixes from cleanups as requested by Jarko.
- rephrase commit messages 

Changes in v3:
- fixed compiler error reported by kernel test robot
- rephrased commit message as suggested by Jarko Sakkinen
- added Reviewed-by tag

Changes in v2:
- rebase against 5.12
- free irq on error path



Lino Sanfilippo (12):
  tpm, tpm_tis: Avoid cache incoherency in test for interrupts
  tpm, tpm_tis: Claim locality before writing TPM_INT_ENABLE register
  tpm, tpm_tis: Disable interrupts if tpm_tis_probe_irq() failed
  tpm, tmp_tis: Claim locality before writing interrupt registers
  tpm, tpm_tis: Only handle supported interrupts
  tpm, tpm_tis: Move interrupt mask checks into own function
  tpm, tpm_tis: do not check for the active locality in interrupt
    handler
  tpm, tpm: Implement usage counter for locality
  tpm, tpm_tis: Request threaded interrupt handler
  tpm, tpm_tis: Claim locality in interrupt handler
  tpm, tpm_tis: Claim locality when interrupts are reenabled on resume
  tpm, tpm_tis: Enable interrupt test

 drivers/char/tpm/tpm_tis.c      |   2 +-
 drivers/char/tpm/tpm_tis_core.c | 279 ++++++++++++++++++++------------
 drivers/char/tpm/tpm_tis_core.h |   5 +-
 3 files changed, 185 insertions(+), 101 deletions(-)


base-commit: 30a0b95b1335e12efef89dd78518ed3e4a71a763
-- 
2.36.1


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v9 01/12] tpm, tpm_tis: Avoid cache incoherency in test for interrupts
  2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
@ 2022-11-10 15:25 ` Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 02/12] tpm, tpm_tis: Claim locality before writing TPM_INT_ENABLE register Lino Sanfilippo
                   ` (10 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

The interrupt handler that sets the boolean variable irq_tested may run on
another CPU as the thread that checks irq_tested as part of the irq test in
tmp_tis_send().

Since nothing guarantees cache coherency between CPUs for unsynchronized
accesses to boolean variables the testing thread might not perceive the
value change done in the interrupt handler.

Avoid this issue by setting the bit TPM_TIS_IRQ_TESTED in the flags field
of the tpm_tis_data struct and by accessing this field with the bit
manipulating functions that provide cache coherency.

Also convert all other existing sites to use the proper macros when
accessing this bitfield.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Michael Niewöhner <linux@mniewoehner.de>
---
 drivers/char/tpm/tpm_tis.c      |  2 +-
 drivers/char/tpm/tpm_tis_core.c | 21 +++++++++++----------
 drivers/char/tpm/tpm_tis_core.h |  2 +-
 3 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
index bcff6429e0b4..ce43412eb398 100644
--- a/drivers/char/tpm/tpm_tis.c
+++ b/drivers/char/tpm/tpm_tis.c
@@ -226,7 +226,7 @@ static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info)
 		irq = tpm_info->irq;
 
 	if (itpm || is_itpm(ACPI_COMPANION(dev)))
-		phy->priv.flags |= TPM_TIS_ITPM_WORKAROUND;
+		set_bit(TPM_TIS_ITPM_WORKAROUND, &phy->priv.flags);
 
 	return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg,
 				 ACPI_HANDLE(dev));
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 757623bacfd5..c0008efb95dc 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -351,7 +351,7 @@ static int tpm_tis_send_data(struct tpm_chip *chip, const u8 *buf, size_t len)
 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 	int rc, status, burstcnt;
 	size_t count = 0;
-	bool itpm = priv->flags & TPM_TIS_ITPM_WORKAROUND;
+	bool itpm = test_bit(TPM_TIS_ITPM_WORKAROUND, &priv->flags);
 
 	status = tpm_tis_status(chip);
 	if ((status & TPM_STS_COMMAND_READY) == 0) {
@@ -484,7 +484,8 @@ static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
 	int rc, irq;
 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 
-	if (!(chip->flags & TPM_CHIP_FLAG_IRQ) || priv->irq_tested)
+	if (!(chip->flags & TPM_CHIP_FLAG_IRQ) ||
+	     test_bit(TPM_TIS_IRQ_TESTED, &priv->flags))
 		return tpm_tis_send_main(chip, buf, len);
 
 	/* Verify receipt of the expected IRQ */
@@ -494,11 +495,11 @@ static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
 	rc = tpm_tis_send_main(chip, buf, len);
 	priv->irq = irq;
 	chip->flags |= TPM_CHIP_FLAG_IRQ;
-	if (!priv->irq_tested)
+	if (!test_bit(TPM_TIS_IRQ_TESTED, &priv->flags))
 		tpm_msleep(1);
-	if (!priv->irq_tested)
+	if (!test_bit(TPM_TIS_IRQ_TESTED, &priv->flags))
 		disable_interrupts(chip);
-	priv->irq_tested = true;
+	set_bit(TPM_TIS_IRQ_TESTED, &priv->flags);
 	return rc;
 }
 
@@ -641,7 +642,7 @@ static int probe_itpm(struct tpm_chip *chip)
 	size_t len = sizeof(cmd_getticks);
 	u16 vendor;
 
-	if (priv->flags & TPM_TIS_ITPM_WORKAROUND)
+	if (test_bit(TPM_TIS_ITPM_WORKAROUND, &priv->flags))
 		return 0;
 
 	rc = tpm_tis_read16(priv, TPM_DID_VID(0), &vendor);
@@ -661,13 +662,13 @@ static int probe_itpm(struct tpm_chip *chip)
 
 	tpm_tis_ready(chip);
 
-	priv->flags |= TPM_TIS_ITPM_WORKAROUND;
+	set_bit(TPM_TIS_ITPM_WORKAROUND, &priv->flags);
 
 	rc = tpm_tis_send_data(chip, cmd_getticks, len);
 	if (rc == 0)
 		dev_info(&chip->dev, "Detected an iTPM.\n");
 	else {
-		priv->flags &= ~TPM_TIS_ITPM_WORKAROUND;
+		clear_bit(TPM_TIS_ITPM_WORKAROUND, &priv->flags);
 		rc = -EFAULT;
 	}
 
@@ -707,7 +708,7 @@ static irqreturn_t tis_int_handler(int dummy, void *dev_id)
 	if (interrupt == 0)
 		return IRQ_NONE;
 
-	priv->irq_tested = true;
+	set_bit(TPM_TIS_IRQ_TESTED, &priv->flags);
 	if (interrupt & TPM_INTF_DATA_AVAIL_INT)
 		wake_up_interruptible(&priv->read_queue);
 	if (interrupt & TPM_INTF_LOCALITY_CHANGE_INT)
@@ -793,7 +794,7 @@ static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
 	if (rc < 0)
 		return rc;
 
-	priv->irq_tested = false;
+	clear_bit(TPM_TIS_IRQ_TESTED, &priv->flags);
 
 	/* Generate an interrupt by having the core call through to
 	 * tpm_tis_send
diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h
index 66a5a13cd1df..695a2516dce0 100644
--- a/drivers/char/tpm/tpm_tis_core.h
+++ b/drivers/char/tpm/tpm_tis_core.h
@@ -86,13 +86,13 @@ enum tis_defaults {
 enum tpm_tis_flags {
 	TPM_TIS_ITPM_WORKAROUND		= BIT(0),
 	TPM_TIS_INVALID_STATUS		= BIT(1),
+	TPM_TIS_IRQ_TESTED		= BIT(2),
 };
 
 struct tpm_tis_data {
 	u16 manufacturer_id;
 	int locality;
 	int irq;
-	bool irq_tested;
 	unsigned long flags;
 	void __iomem *ilb_base_addr;
 	u16 clkrun_enabled;
-- 
2.36.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v9 02/12] tpm, tpm_tis: Claim locality before writing TPM_INT_ENABLE register
  2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 01/12] tpm, tpm_tis: Avoid cache incoherency in test for interrupts Lino Sanfilippo
@ 2022-11-10 15:25 ` Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 03/12] tpm, tpm_tis: Disable interrupts if tpm_tis_probe_irq() failed Lino Sanfilippo
                   ` (9 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

In disable_interrupts() the TPM_GLOBAL_INT_ENABLE bit is unset in the
TPM_INT_ENABLE register to shut the interrupts off. However modifying the
register is only possible with a held locality. So claim the locality
before disable_interrupts() is called.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Michael Niewöhner <linux@mniewoehner.de>
---
 drivers/char/tpm/tpm_tis_core.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index c0008efb95dc..d2c9c9d76893 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -1098,7 +1098,11 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 				dev_err(&chip->dev, FW_BUG
 					"TPM interrupt not working, polling instead\n");
 
+				rc = request_locality(chip, 0);
+				if (rc < 0)
+					goto out_err;
 				disable_interrupts(chip);
+				release_locality(chip, 0);
 			}
 		} else {
 			tpm_tis_probe_irq(chip, intmask);
-- 
2.36.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v9 03/12] tpm, tpm_tis: Disable interrupts if tpm_tis_probe_irq() failed
  2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 01/12] tpm, tpm_tis: Avoid cache incoherency in test for interrupts Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 02/12] tpm, tpm_tis: Claim locality before writing TPM_INT_ENABLE register Lino Sanfilippo
@ 2022-11-10 15:25 ` Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 04/12] tpm, tmp_tis: Claim locality before writing interrupt registers Lino Sanfilippo
                   ` (8 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

Both functions tpm_tis_probe_irq_single() and tpm_tis_probe_irq() may setup
the interrupts and then return with an error. This case is indicated by a
missing TPM_CHIP_FLAG_IRQ flag in chip->flags.
Currently the interrupt setup is only undone if tpm_tis_probe_irq_single()
fails. Undo the setup also if tpm_tis_probe_irq() fails.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Michael Niewöhner <linux@mniewoehner.de>
---
 drivers/char/tpm/tpm_tis_core.c | 22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index d2c9c9d76893..603b82ca56da 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -1091,21 +1091,21 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 			goto out_err;
 		}
 
-		if (irq) {
+		if (irq)
 			tpm_tis_probe_irq_single(chip, intmask, IRQF_SHARED,
 						 irq);
-			if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) {
-				dev_err(&chip->dev, FW_BUG
+		else
+			tpm_tis_probe_irq(chip, intmask);
+
+		if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) {
+			dev_err(&chip->dev, FW_BUG
 					"TPM interrupt not working, polling instead\n");
 
-				rc = request_locality(chip, 0);
-				if (rc < 0)
-					goto out_err;
-				disable_interrupts(chip);
-				release_locality(chip, 0);
-			}
-		} else {
-			tpm_tis_probe_irq(chip, intmask);
+			rc = request_locality(chip, 0);
+			if (rc < 0)
+				goto out_err;
+			disable_interrupts(chip);
+			release_locality(chip, 0);
 		}
 	}
 
-- 
2.36.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v9 04/12] tpm, tmp_tis: Claim locality before writing interrupt registers
  2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
                   ` (2 preceding siblings ...)
  2022-11-10 15:25 ` [PATCH v9 03/12] tpm, tpm_tis: Disable interrupts if tpm_tis_probe_irq() failed Lino Sanfilippo
@ 2022-11-10 15:25 ` Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 05/12] tpm, tpm_tis: Only handle supported interrupts Lino Sanfilippo
                   ` (7 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

In tpm_tis_probe_single_irq() interrupt registers TPM_INT_VECTOR,
TPM_INT_STATUS and TPM_INT_ENABLE are modified to setup the interrupts.
Currently these modifications are done without holding a locality thus they
have no effect. Fix this by claiming the (default) locality before the
registers are written.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Michael Niewöhner <linux@mniewoehner.de>
---
 drivers/char/tpm/tpm_tis_core.c | 25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 603b82ca56da..52205a1fee9e 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -770,30 +770,45 @@ static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
 	}
 	priv->irq = irq;
 
+	rc = request_locality(chip, 0);
+	if (rc < 0)
+		return rc;
+
 	rc = tpm_tis_read8(priv, TPM_INT_VECTOR(priv->locality),
 			   &original_int_vec);
-	if (rc < 0)
+	if (rc < 0) {
+		release_locality(chip, priv->locality);
 		return rc;
+	}
 
 	rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), irq);
-	if (rc < 0)
+	if (rc < 0) {
+		release_locality(chip, priv->locality);
 		return rc;
+	}
 
 	rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &int_status);
-	if (rc < 0)
+	if (rc < 0) {
+		release_locality(chip, priv->locality);
 		return rc;
+	}
 
 	/* Clear all existing */
 	rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), int_status);
-	if (rc < 0)
+	if (rc < 0) {
+		release_locality(chip, priv->locality);
 		return rc;
+	}
 
 	/* Turn on */
 	rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality),
 			     intmask | TPM_GLOBAL_INT_ENABLE);
-	if (rc < 0)
+	if (rc < 0) {
+		release_locality(chip, priv->locality);
 		return rc;
+	}
 
+	release_locality(chip, priv->locality);
 	clear_bit(TPM_TIS_IRQ_TESTED, &priv->flags);
 
 	/* Generate an interrupt by having the core call through to
-- 
2.36.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v9 05/12] tpm, tpm_tis: Only handle supported interrupts
  2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
                   ` (3 preceding siblings ...)
  2022-11-10 15:25 ` [PATCH v9 04/12] tpm, tmp_tis: Claim locality before writing interrupt registers Lino Sanfilippo
@ 2022-11-10 15:25 ` Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 06/12] tpm, tpm_tis: Move interrupt mask checks into own function Lino Sanfilippo
                   ` (6 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

According to the TPM Interface Specification (TIS) support for "stsValid"
and "commandReady" interrupts is only optional.
This has to be taken into account when handling the interrupts in functions
like wait_for_tpm_stat(). To determine the supported interrupts use the
capability query.

Also adjust wait_for_tpm_stat() to only wait for interrupt reported status
changes. After that process all the remaining status changes by polling
the status register.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Tested-by: Michael Niewöhner <linux@mniewoehner.de>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
---
 drivers/char/tpm/tpm_tis_core.c | 120 +++++++++++++++++++-------------
 drivers/char/tpm/tpm_tis_core.h |   1 +
 2 files changed, 73 insertions(+), 48 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 52205a1fee9e..d07debc3182c 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -53,41 +53,63 @@ static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask,
 	long rc;
 	u8 status;
 	bool canceled = false;
+	u8 sts_mask = 0;
+	int ret = 0;
 
 	/* check current status */
 	status = chip->ops->status(chip);
 	if ((status & mask) == mask)
 		return 0;
 
-	stop = jiffies + timeout;
+	/* check what status changes can be handled by irqs */
+	if (priv->int_mask & TPM_INTF_STS_VALID_INT)
+		sts_mask |= TPM_STS_VALID;
 
-	if (chip->flags & TPM_CHIP_FLAG_IRQ) {
+	if (priv->int_mask & TPM_INTF_DATA_AVAIL_INT)
+		sts_mask |= TPM_STS_DATA_AVAIL;
+
+	if (priv->int_mask & TPM_INTF_CMD_READY_INT)
+		sts_mask |= TPM_STS_COMMAND_READY;
+
+	sts_mask &= mask;
+
+	stop = jiffies + timeout;
+	/* process status changes with irq support */
+	if (sts_mask) {
+		ret = -ETIME;
 again:
 		timeout = stop - jiffies;
 		if ((long)timeout <= 0)
 			return -ETIME;
 		rc = wait_event_interruptible_timeout(*queue,
-			wait_for_tpm_stat_cond(chip, mask, check_cancel,
+			wait_for_tpm_stat_cond(chip, sts_mask, check_cancel,
 					       &canceled),
 			timeout);
 		if (rc > 0) {
 			if (canceled)
 				return -ECANCELED;
-			return 0;
+			ret = 0;
 		}
 		if (rc == -ERESTARTSYS && freezing(current)) {
 			clear_thread_flag(TIF_SIGPENDING);
 			goto again;
 		}
-	} else {
-		do {
-			usleep_range(priv->timeout_min,
-				     priv->timeout_max);
-			status = chip->ops->status(chip);
-			if ((status & mask) == mask)
-				return 0;
-		} while (time_before(jiffies, stop));
 	}
+
+	if (ret)
+		return ret;
+
+	mask &= ~sts_mask;
+	if (!mask) /* all done */
+		return 0;
+	/* process status changes without irq support */
+	do {
+		status = chip->ops->status(chip);
+		if ((status & mask) == mask)
+			return 0;
+		usleep_range(priv->timeout_min,
+			     priv->timeout_max);
+	} while (time_before(jiffies, stop));
 	return -ETIME;
 }
 
@@ -1021,8 +1043,40 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 	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;
+	/* 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) {
+		intmask |= 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) {
+		intmask |= TPM_INTF_LOCALITY_CHANGE_INT;
+		dev_dbg(dev, "\tLocality Change Int Support\n");
+	}
+	if (intfcaps & TPM_INTF_STS_VALID_INT) {
+		intmask |= TPM_INTF_STS_VALID_INT;
+		dev_dbg(dev, "\tSts Valid Int Support\n");
+	}
+	if (intfcaps & TPM_INTF_DATA_AVAIL_INT) {
+		intmask |= TPM_INTF_DATA_AVAIL_INT;
+		dev_dbg(dev, "\tData Avail Int Support\n");
+	}
+
 	intmask &= ~TPM_GLOBAL_INT_ENABLE;
 
 	rc = request_locality(chip, 0);
@@ -1056,32 +1110,6 @@ 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);
@@ -1112,7 +1140,9 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 		else
 			tpm_tis_probe_irq(chip, intmask);
 
-		if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) {
+		if (chip->flags & TPM_CHIP_FLAG_IRQ) {
+			priv->int_mask = intmask;
+		} else {
 			dev_err(&chip->dev, FW_BUG
 					"TPM interrupt not working, polling instead\n");
 
@@ -1159,13 +1189,7 @@ static void tpm_tis_reenable_interrupts(struct tpm_chip *chip)
 	if (rc < 0)
 		goto out;
 
-	rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
-	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 = priv->int_mask | 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 695a2516dce0..2deef11c88db 100644
--- a/drivers/char/tpm/tpm_tis_core.h
+++ b/drivers/char/tpm/tpm_tis_core.h
@@ -93,6 +93,7 @@ struct tpm_tis_data {
 	u16 manufacturer_id;
 	int locality;
 	int irq;
+	unsigned int int_mask;
 	unsigned long flags;
 	void __iomem *ilb_base_addr;
 	u16 clkrun_enabled;
-- 
2.36.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v9 06/12] tpm, tpm_tis: Move interrupt mask checks into own function
  2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
                   ` (4 preceding siblings ...)
  2022-11-10 15:25 ` [PATCH v9 05/12] tpm, tpm_tis: Only handle supported interrupts Lino Sanfilippo
@ 2022-11-10 15:25 ` Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 07/12] tpm, tpm_tis: do not check for the active locality in interrupt handler Lino Sanfilippo
                   ` (5 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

Clean up wait_for_tpm_stat() by moving multiple similar interrupt mask
checks into an own function.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Suggested-by: Jarkko Sakkinen <jarkko@kernel.org>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
---
 drivers/char/tpm/tpm_tis_core.c | 29 ++++++++++++++++++-----------
 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index d07debc3182c..181c291b0bb8 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -44,6 +44,20 @@ static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
 	return false;
 }
 
+static u8 tpm_tis_filter_sts_mask(u8 int_mask, u8 sts_mask)
+{
+	if (!(int_mask & TPM_INTF_STS_VALID_INT))
+		sts_mask &= ~TPM_STS_VALID;
+
+	if (!(int_mask & TPM_INTF_DATA_AVAIL_INT))
+		sts_mask &= ~TPM_STS_DATA_AVAIL;
+
+	if (!(int_mask & TPM_INTF_CMD_READY_INT))
+		sts_mask &= ~TPM_STS_COMMAND_READY;
+
+	return sts_mask;
+}
+
 static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask,
 		unsigned long timeout, wait_queue_head_t *queue,
 		bool check_cancel)
@@ -53,7 +67,7 @@ static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask,
 	long rc;
 	u8 status;
 	bool canceled = false;
-	u8 sts_mask = 0;
+	u8 sts_mask;
 	int ret = 0;
 
 	/* check current status */
@@ -61,17 +75,10 @@ static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask,
 	if ((status & mask) == mask)
 		return 0;
 
+	sts_mask = mask & (TPM_STS_VALID | TPM_STS_DATA_AVAIL |
+			   TPM_STS_COMMAND_READY);
 	/* check what status changes can be handled by irqs */
-	if (priv->int_mask & TPM_INTF_STS_VALID_INT)
-		sts_mask |= TPM_STS_VALID;
-
-	if (priv->int_mask & TPM_INTF_DATA_AVAIL_INT)
-		sts_mask |= TPM_STS_DATA_AVAIL;
-
-	if (priv->int_mask & TPM_INTF_CMD_READY_INT)
-		sts_mask |= TPM_STS_COMMAND_READY;
-
-	sts_mask &= mask;
+	sts_mask = tpm_tis_filter_sts_mask(priv->int_mask, sts_mask);
 
 	stop = jiffies + timeout;
 	/* process status changes with irq support */
-- 
2.36.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v9 07/12] tpm, tpm_tis: do not check for the active locality in interrupt handler
  2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
                   ` (5 preceding siblings ...)
  2022-11-10 15:25 ` [PATCH v9 06/12] tpm, tpm_tis: Move interrupt mask checks into own function Lino Sanfilippo
@ 2022-11-10 15:25 ` Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 08/12] tpm, tpm: Implement usage counter for locality Lino Sanfilippo
                   ` (4 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

After driver initialization tpm_tis_data->locality may only be modified in
case of a LOCALITY CHANGE interrupt. In this case the interrupt handler
iterates over all localities only to assign the active one to
tpm_tis_data->locality.

However this information is never used any more, so the assignment is not
needed.
Furthermore without the assignment tpm_tis_data->locality cannot change any
more at driver runtime, and thus no protection against concurrent
modification is required when the variable is read at other places.

So remove this iteration entirely.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
---
 drivers/char/tpm/tpm_tis_core.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 181c291b0bb8..4336f7ea8c2b 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -728,7 +728,7 @@ static irqreturn_t tis_int_handler(int dummy, void *dev_id)
 	struct tpm_chip *chip = dev_id;
 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 	u32 interrupt;
-	int i, rc;
+	int rc;
 
 	rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
 	if (rc < 0)
@@ -740,10 +740,7 @@ static irqreturn_t tis_int_handler(int dummy, void *dev_id)
 	set_bit(TPM_TIS_IRQ_TESTED, &priv->flags);
 	if (interrupt & TPM_INTF_DATA_AVAIL_INT)
 		wake_up_interruptible(&priv->read_queue);
-	if (interrupt & TPM_INTF_LOCALITY_CHANGE_INT)
-		for (i = 0; i < 5; i++)
-			if (check_locality(chip, i))
-				break;
+
 	if (interrupt &
 	    (TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_STS_VALID_INT |
 	     TPM_INTF_CMD_READY_INT))
-- 
2.36.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v9 08/12] tpm, tpm: Implement usage counter for locality
  2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
                   ` (6 preceding siblings ...)
  2022-11-10 15:25 ` [PATCH v9 07/12] tpm, tpm_tis: do not check for the active locality in interrupt handler Lino Sanfilippo
@ 2022-11-10 15:25 ` Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 09/12] tpm, tpm_tis: Request threaded interrupt handler Lino Sanfilippo
                   ` (3 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

Implement a usage counter for the (default) locality used by the TPM TIS
driver:
Request the locality from the TPM if it has not been claimed yet, otherwise
only increment the counter. Also release the locality if the counter is 0
otherwise only decrement the counter. Since in case of SPI the register
accesses are locked by means of the SPI bus mutex use a sleepable lock
(i.e. also a mutex) to ensure thread-safety of the counter which may be
accessed by both a userspace thread and the interrupt handler.

By doing this refactor the names of the amended functions to use a more
appropriate prefix.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Tested-by: Michael Niewöhner <linux@mniewoehner.de>
---
 drivers/char/tpm/tpm_tis_core.c | 75 ++++++++++++++++++++++-----------
 drivers/char/tpm/tpm_tis_core.h |  2 +
 2 files changed, 53 insertions(+), 24 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 4336f7ea8c2b..ecde684a8f80 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -165,16 +165,27 @@ static bool check_locality(struct tpm_chip *chip, int l)
 	return false;
 }
 
-static int release_locality(struct tpm_chip *chip, int l)
+static int __tpm_tis_relinquish_locality(struct tpm_tis_data *priv, int l)
+{
+	tpm_tis_write8(priv, TPM_ACCESS(l), TPM_ACCESS_ACTIVE_LOCALITY);
+
+	return 0;
+}
+
+static int tpm_tis_relinquish_locality(struct tpm_chip *chip, int l)
 {
 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 
-	tpm_tis_write8(priv, TPM_ACCESS(l), TPM_ACCESS_ACTIVE_LOCALITY);
+	mutex_lock(&priv->locality_count_mutex);
+	priv->locality_count--;
+	if (priv->locality_count == 0)
+		__tpm_tis_relinquish_locality(priv, l);
+	mutex_unlock(&priv->locality_count_mutex);
 
 	return 0;
 }
 
-static int request_locality(struct tpm_chip *chip, int l)
+static int __tpm_tis_request_locality(struct tpm_chip *chip, int l)
 {
 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 	unsigned long stop, timeout;
@@ -215,6 +226,20 @@ static int request_locality(struct tpm_chip *chip, int l)
 	return -1;
 }
 
+static int tpm_tis_request_locality(struct tpm_chip *chip, int l)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	int ret = 0;
+
+	mutex_lock(&priv->locality_count_mutex);
+	if (priv->locality_count == 0)
+		ret = __tpm_tis_request_locality(chip, l);
+	if (!ret)
+		priv->locality_count++;
+	mutex_unlock(&priv->locality_count_mutex);
+	return ret;
+}
+
 static u8 tpm_tis_status(struct tpm_chip *chip)
 {
 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
@@ -682,7 +707,7 @@ static int probe_itpm(struct tpm_chip *chip)
 	if (vendor != TPM_VID_INTEL)
 		return 0;
 
-	if (request_locality(chip, 0) != 0)
+	if (tpm_tis_request_locality(chip, 0) != 0)
 		return -EBUSY;
 
 	rc = tpm_tis_send_data(chip, cmd_getticks, len);
@@ -703,7 +728,7 @@ static int probe_itpm(struct tpm_chip *chip)
 
 out:
 	tpm_tis_ready(chip);
-	release_locality(chip, priv->locality);
+	tpm_tis_relinquish_locality(chip, priv->locality);
 
 	return rc;
 }
@@ -762,7 +787,7 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
 	cap_t cap;
 	int ret;
 
-	ret = request_locality(chip, 0);
+	ret = tpm_tis_request_locality(chip, 0);
 	if (ret < 0)
 		return ret;
 
@@ -771,7 +796,7 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
 	else
 		ret = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc, 0);
 
-	release_locality(chip, 0);
+	tpm_tis_relinquish_locality(chip, 0);
 
 	return ret;
 }
@@ -796,33 +821,33 @@ static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
 	}
 	priv->irq = irq;
 
-	rc = request_locality(chip, 0);
+	rc = tpm_tis_request_locality(chip, 0);
 	if (rc < 0)
 		return rc;
 
 	rc = tpm_tis_read8(priv, TPM_INT_VECTOR(priv->locality),
 			   &original_int_vec);
 	if (rc < 0) {
-		release_locality(chip, priv->locality);
+		tpm_tis_relinquish_locality(chip, priv->locality);
 		return rc;
 	}
 
 	rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), irq);
 	if (rc < 0) {
-		release_locality(chip, priv->locality);
+		tpm_tis_relinquish_locality(chip, priv->locality);
 		return rc;
 	}
 
 	rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &int_status);
 	if (rc < 0) {
-		release_locality(chip, priv->locality);
+		tpm_tis_relinquish_locality(chip, priv->locality);
 		return rc;
 	}
 
 	/* Clear all existing */
 	rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), int_status);
 	if (rc < 0) {
-		release_locality(chip, priv->locality);
+		tpm_tis_relinquish_locality(chip, priv->locality);
 		return rc;
 	}
 
@@ -830,11 +855,11 @@ static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
 	rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality),
 			     intmask | TPM_GLOBAL_INT_ENABLE);
 	if (rc < 0) {
-		release_locality(chip, priv->locality);
+		tpm_tis_relinquish_locality(chip, priv->locality);
 		return rc;
 	}
 
-	release_locality(chip, priv->locality);
+	tpm_tis_relinquish_locality(chip, priv->locality);
 	clear_bit(TPM_TIS_IRQ_TESTED, &priv->flags);
 
 	/* Generate an interrupt by having the core call through to
@@ -970,8 +995,8 @@ static const struct tpm_class_ops tpm_tis = {
 	.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 	.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 	.req_canceled = tpm_tis_req_canceled,
-	.request_locality = request_locality,
-	.relinquish_locality = release_locality,
+	.request_locality = tpm_tis_request_locality,
+	.relinquish_locality = tpm_tis_relinquish_locality,
 	.clk_enable = tpm_tis_clkrun_enable,
 };
 
@@ -1005,6 +1030,8 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 	priv->timeout_min = TPM_TIMEOUT_USECS_MIN;
 	priv->timeout_max = TPM_TIMEOUT_USECS_MAX;
 	priv->phy_ops = phy_ops;
+	priv->locality_count = 0;
+	mutex_init(&priv->locality_count_mutex);
 
 	dev_set_drvdata(&chip->dev, priv);
 
@@ -1083,14 +1110,14 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 
 	intmask &= ~TPM_GLOBAL_INT_ENABLE;
 
-	rc = request_locality(chip, 0);
+	rc = tpm_tis_request_locality(chip, 0);
 	if (rc < 0) {
 		rc = -ENODEV;
 		goto out_err;
 	}
 
 	tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
-	release_locality(chip, 0);
+	tpm_tis_relinquish_locality(chip, 0);
 
 	rc = tpm_chip_start(chip);
 	if (rc)
@@ -1124,13 +1151,13 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 		 * proper timeouts for the driver.
 		 */
 
-		rc = request_locality(chip, 0);
+		rc = tpm_tis_request_locality(chip, 0);
 		if (rc < 0)
 			goto out_err;
 
 		rc = tpm_get_timeouts(chip);
 
-		release_locality(chip, 0);
+		tpm_tis_relinquish_locality(chip, 0);
 
 		if (rc) {
 			dev_err(dev, "Could not get TPM timeouts and durations\n");
@@ -1150,11 +1177,11 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 			dev_err(&chip->dev, FW_BUG
 					"TPM interrupt not working, polling instead\n");
 
-			rc = request_locality(chip, 0);
+			rc = tpm_tis_request_locality(chip, 0);
 			if (rc < 0)
 				goto out_err;
 			disable_interrupts(chip);
-			release_locality(chip, 0);
+			tpm_tis_relinquish_locality(chip, 0);
 		}
 	}
 
@@ -1221,13 +1248,13 @@ int tpm_tis_resume(struct device *dev)
 	 * an error code but for unknown reason it isn't handled.
 	 */
 	if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
-		ret = request_locality(chip, 0);
+		ret = tpm_tis_request_locality(chip, 0);
 		if (ret < 0)
 			return ret;
 
 		tpm1_do_selftest(chip);
 
-		release_locality(chip, 0);
+		tpm_tis_relinquish_locality(chip, 0);
 	}
 
 	return 0;
diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h
index 2deef11c88db..13bdcf38e56f 100644
--- a/drivers/char/tpm/tpm_tis_core.h
+++ b/drivers/char/tpm/tpm_tis_core.h
@@ -91,6 +91,8 @@ enum tpm_tis_flags {
 
 struct tpm_tis_data {
 	u16 manufacturer_id;
+	struct mutex locality_count_mutex;
+	unsigned int locality_count;
 	int locality;
 	int irq;
 	unsigned int int_mask;
-- 
2.36.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v9 09/12] tpm, tpm_tis: Request threaded interrupt handler
  2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
                   ` (7 preceding siblings ...)
  2022-11-10 15:25 ` [PATCH v9 08/12] tpm, tpm: Implement usage counter for locality Lino Sanfilippo
@ 2022-11-10 15:25 ` Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 10/12] tpm, tpm_tis: Claim locality in " Lino Sanfilippo
                   ` (2 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

The TIS interrupt handler at least has to read and write the interrupt
status register. In case of SPI both operations result in a call to
tpm_tis_spi_transfer() which uses the bus_lock_mutex of the spi device
and thus must only be called from a sleepable context.

To ensure this request a threaded interrupt handler.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Tested-by: Michael Niewöhner <linux@mniewoehner.de>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
---
 drivers/char/tpm/tpm_tis_core.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index ecde684a8f80..ced8eae3e4d5 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -813,8 +813,11 @@ static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
 	int rc;
 	u32 int_status;
 
-	if (devm_request_irq(chip->dev.parent, irq, tis_int_handler, flags,
-			     dev_name(&chip->dev), chip) != 0) {
+
+	rc = devm_request_threaded_irq(chip->dev.parent, irq, NULL,
+				       tis_int_handler, IRQF_ONESHOT | flags,
+				       dev_name(&chip->dev), chip);
+	if (rc) {
 		dev_info(&chip->dev, "Unable to request irq: %d for probe\n",
 			 irq);
 		return -1;
-- 
2.36.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v9 10/12] tpm, tpm_tis: Claim locality in interrupt handler
  2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
                   ` (8 preceding siblings ...)
  2022-11-10 15:25 ` [PATCH v9 09/12] tpm, tpm_tis: Request threaded interrupt handler Lino Sanfilippo
@ 2022-11-10 15:25 ` Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 11/12] tpm, tpm_tis: Claim locality when interrupts are reenabled on resume Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 12/12] tpm, tpm_tis: Enable interrupt test Lino Sanfilippo
  11 siblings, 0 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

Writing the TPM_INT_STATUS register in the interrupt handler to clear the
interrupts only has effect if a locality is held. Since this is not
guaranteed at the time the interrupt is fired, claim the locality
explicitly in the handler.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Michael Niewöhner <linux@mniewoehner.de>
---
 drivers/char/tpm/tpm_tis_core.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index ced8eae3e4d5..a0a1b1a3ddc6 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -772,7 +772,9 @@ static irqreturn_t tis_int_handler(int dummy, void *dev_id)
 		wake_up_interruptible(&priv->int_queue);
 
 	/* Clear interrupts handled with TPM_EOI */
+	tpm_tis_request_locality(chip, 0);
 	rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), interrupt);
+	tpm_tis_relinquish_locality(chip, 0);
 	if (rc < 0)
 		return IRQ_NONE;
 
-- 
2.36.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v9 11/12] tpm, tpm_tis: Claim locality when interrupts are reenabled on resume
  2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
                   ` (9 preceding siblings ...)
  2022-11-10 15:25 ` [PATCH v9 10/12] tpm, tpm_tis: Claim locality in " Lino Sanfilippo
@ 2022-11-10 15:25 ` Lino Sanfilippo
  2022-11-10 15:25 ` [PATCH v9 12/12] tpm, tpm_tis: Enable interrupt test Lino Sanfilippo
  11 siblings, 0 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

In tpm_tis_resume() make sure that the locality has been claimed when
tpm_tis_reenable_interrupts() is called. Otherwise the writings to the
register might not have any effect.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
---
 drivers/char/tpm/tpm_tis_core.c | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index a0a1b1a3ddc6..469a1db95941 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -1241,28 +1241,27 @@ int tpm_tis_resume(struct device *dev)
 	struct tpm_chip *chip = dev_get_drvdata(dev);
 	int ret;
 
+	ret = tpm_tis_request_locality(chip, 0);
+	if (ret < 0)
+		return ret;
+
 	if (chip->flags & TPM_CHIP_FLAG_IRQ)
 		tpm_tis_reenable_interrupts(chip);
 
 	ret = tpm_pm_resume(dev);
 	if (ret)
-		return ret;
+		goto out;
 
 	/*
 	 * TPM 1.2 requires self-test on resume. This function actually returns
 	 * an error code but for unknown reason it isn't handled.
 	 */
-	if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
-		ret = tpm_tis_request_locality(chip, 0);
-		if (ret < 0)
-			return ret;
-
+	if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
 		tpm1_do_selftest(chip);
+out:
+	tpm_tis_relinquish_locality(chip, 0);
 
-		tpm_tis_relinquish_locality(chip, 0);
-	}
-
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(tpm_tis_resume);
 #endif
-- 
2.36.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v9 12/12] tpm, tpm_tis: Enable interrupt test
  2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
                   ` (10 preceding siblings ...)
  2022-11-10 15:25 ` [PATCH v9 11/12] tpm, tpm_tis: Claim locality when interrupts are reenabled on resume Lino Sanfilippo
@ 2022-11-10 15:25 ` Lino Sanfilippo
  2022-11-14 13:35   ` Lino Sanfilippo
  11 siblings, 1 reply; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-10 15:25 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, LinoSanfilippo, lukas, p.rosenberger

From: Lino Sanfilippo <l.sanfilippo@kunbus.com>

The test for interrupts in tpm_tis_send() is skipped if the flag
TPM_CHIP_FLAG_IRQ is not set. Since the current code never sets the flag
initially the test is never executed.

Fix this by setting the flag in tpm_tis_gen_interrupt() right after
interrupts have been enabled and before the test is executed.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
---
 drivers/char/tpm/tpm_tis_core.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 469a1db95941..1f78582264eb 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -793,6 +793,8 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
 	if (ret < 0)
 		return ret;
 
+	chip->flags |= TPM_CHIP_FLAG_IRQ;
+
 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
 		ret = tpm2_get_tpm_pt(chip, 0x100, &cap2, desc);
 	else
-- 
2.36.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Re: [PATCH v9 12/12] tpm, tpm_tis: Enable interrupt test
  2022-11-10 15:25 ` [PATCH v9 12/12] tpm, tpm_tis: Enable interrupt test Lino Sanfilippo
@ 2022-11-14 13:35   ` Lino Sanfilippo
  0 siblings, 0 replies; 14+ messages in thread
From: Lino Sanfilippo @ 2022-11-14 13:35 UTC (permalink / raw)
  To: peterhuewe, jarkko, jgg
  Cc: stefanb, linux, linux-integrity, linux-kernel, jandryuk, pmenzel,
	l.sanfilippo, lukas, p.rosenberger



On 10.11.22 16:25, Lino Sanfilippo wrote:
> From: Lino Sanfilippo <l.sanfilippo@kunbus.com>
>
> The test for interrupts in tpm_tis_send() is skipped if the flag
> TPM_CHIP_FLAG_IRQ is not set. Since the current code never sets the flag
> initially the test is never executed.
>
> Fix this by setting the flag in tpm_tis_gen_interrupt() right after
> interrupts have been enabled and before the test is executed.
>
> Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
> ---
>  drivers/char/tpm/tpm_tis_core.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
> index 469a1db95941..1f78582264eb 100644
> --- a/drivers/char/tpm/tpm_tis_core.c
> +++ b/drivers/char/tpm/tpm_tis_core.c
> @@ -793,6 +793,8 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
>  	if (ret < 0)
>  		return ret;
>
> +	chip->flags |= TPM_CHIP_FLAG_IRQ;
> +
>  	if (chip->flags & TPM_CHIP_FLAG_TPM2)
>  		ret = tpm2_get_tpm_pt(chip, 0x100, &cap2, desc);
>  	else

Please ignore this patch. I will send another version in a v10 of this series.

Regards,
Lino

^ permalink raw reply	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2022-11-14 13:36 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-11-10 15:25 [PATCH v9 00/12] TPM IRQ fixes Lino Sanfilippo
2022-11-10 15:25 ` [PATCH v9 01/12] tpm, tpm_tis: Avoid cache incoherency in test for interrupts Lino Sanfilippo
2022-11-10 15:25 ` [PATCH v9 02/12] tpm, tpm_tis: Claim locality before writing TPM_INT_ENABLE register Lino Sanfilippo
2022-11-10 15:25 ` [PATCH v9 03/12] tpm, tpm_tis: Disable interrupts if tpm_tis_probe_irq() failed Lino Sanfilippo
2022-11-10 15:25 ` [PATCH v9 04/12] tpm, tmp_tis: Claim locality before writing interrupt registers Lino Sanfilippo
2022-11-10 15:25 ` [PATCH v9 05/12] tpm, tpm_tis: Only handle supported interrupts Lino Sanfilippo
2022-11-10 15:25 ` [PATCH v9 06/12] tpm, tpm_tis: Move interrupt mask checks into own function Lino Sanfilippo
2022-11-10 15:25 ` [PATCH v9 07/12] tpm, tpm_tis: do not check for the active locality in interrupt handler Lino Sanfilippo
2022-11-10 15:25 ` [PATCH v9 08/12] tpm, tpm: Implement usage counter for locality Lino Sanfilippo
2022-11-10 15:25 ` [PATCH v9 09/12] tpm, tpm_tis: Request threaded interrupt handler Lino Sanfilippo
2022-11-10 15:25 ` [PATCH v9 10/12] tpm, tpm_tis: Claim locality in " Lino Sanfilippo
2022-11-10 15:25 ` [PATCH v9 11/12] tpm, tpm_tis: Claim locality when interrupts are reenabled on resume Lino Sanfilippo
2022-11-10 15:25 ` [PATCH v9 12/12] tpm, tpm_tis: Enable interrupt test Lino Sanfilippo
2022-11-14 13:35   ` Lino Sanfilippo

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.