From 1d6133123fb2626499e0e0a9d62e39bcdc5e593b Mon Sep 17 00:00:00 2001

From: Marco Chiappero <marco.chiappero@intel.com>

Date: Wed, 17 Nov 2021 14:30:43 +0000

Subject: [PATCH] crypto: qat - handle retries due to collisions in

 adf_iov_putmsg()

Git-commit: 1d6133123fb2626499e0e0a9d62e39bcdc5e593b

Patch-mainline: v5.17-rc1

References: jsc#PED-1073

Rework __adf_iov_putmsg() to handle retries due to collisions

internally, removing the need for an external retry loop.

The functions __adf_iov_putmsg() and adf_iov_putmsg() have been merged

together maintaining the adf_iov_putmsg() name.

This will allow to use this function only for GEN2 devices, since

collision are peculiar of this generation and therefore should be

confined to the actual implementation of the transport/medium access.

Note that now adf_iov_putmsg() will retry to send a message only in case

of collisions and will now fail if an ACK is not received from the

remote function.

Signed-off-by: Marco Chiappero <marco.chiappero@intel.com>

Co-developed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>

Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Signed-off-by: Torsten Duwe <duwe@suse.de>

---

 drivers/crypto/qat/qat_common/adf_pf2vf_msg.c | 52 +++++++------------

 1 file changed, 19 insertions(+), 33 deletions(-)

diff --git a/drivers/crypto/qat/qat_common/adf_pf2vf_msg.c b/drivers/crypto/qat/qat_common/adf_pf2vf_msg.c

index 201744825e23a..d98e3639c9d28 100644

--- a/drivers/crypto/qat/qat_common/adf_pf2vf_msg.c

+++ b/drivers/crypto/qat/qat_common/adf_pf2vf_msg.c

@@ -14,7 +14,7 @@

 					 ADF_PFVF_MSG_ACK_MAX_RETRY + \

 					 ADF_PFVF_MSG_COLLISION_DETECT_DELAY)

-static int __adf_iov_putmsg(struct adf_accel_dev *accel_dev, u32 msg, u8 vf_nr)

+static int adf_iov_putmsg(struct adf_accel_dev *accel_dev, u32 msg, u8 vf_nr)

 {

 	struct adf_accel_pci *pci_info = &accel_dev->accel_pci_dev;

 	struct adf_hw_device_data *hw_data = accel_dev->hw_device;

@@ -24,8 +24,9 @@ static int __adf_iov_putmsg(struct adf_accel_dev *accel_dev, u32 msg, u8 vf_nr)

 	u32 local_in_use_mask, local_in_use_pattern;

 	u32 remote_in_use_mask, remote_in_use_pattern;

 	struct mutex *lock;	/* lock preventing concurrent acces of CSR */

+	unsigned int retries = ADF_PFVF_MSG_MAX_RETRIES;

 	u32 int_bit;

-	int ret = 0;

+	int ret;

 	if (accel_dev->is_vf) {

 		pf2vf_offset = hw_data->get_pf2vf_offset(0);

@@ -45,20 +46,22 @@ static int __adf_iov_putmsg(struct adf_accel_dev *accel_dev, u32 msg, u8 vf_nr)

 		int_bit = ADF_PF2VF_INT;

 	}

+	msg &= ~local_in_use_mask;

+	msg |= local_in_use_pattern;

+

 	mutex_lock(lock);

+start:

+	ret = 0;

+

 	/* Check if the PFVF CSR is in use by remote function */

 	val = ADF_CSR_RD(pmisc_bar_addr, pf2vf_offset);

 	if ((val & remote_in_use_mask) == remote_in_use_pattern) {

 		dev_dbg(&GET_DEV(accel_dev),

 			"PFVF CSR in use by remote function\n");

-		ret = -EBUSY;

-		goto out;

+		goto retry;

 	}

-	msg &= ~local_in_use_mask;

-	msg |= local_in_use_pattern;

-

 	/* Attempt to get ownership of the PFVF CSR */

 	ADF_CSR_WR(pmisc_bar_addr, pf2vf_offset, msg | int_bit);

@@ -77,8 +80,7 @@ static int __adf_iov_putmsg(struct adf_accel_dev *accel_dev, u32 msg, u8 vf_nr)

 	if (val != msg) {

 		dev_dbg(&GET_DEV(accel_dev),

 			"Collision - PFVF CSR overwritten by remote function\n");

-		ret = -EIO;

-		goto out;

+		goto retry;

 	}

 	/* Finished with the PFVF CSR; relinquish it and leave msg in CSR */

@@ -86,31 +88,15 @@ static int __adf_iov_putmsg(struct adf_accel_dev *accel_dev, u32 msg, u8 vf_nr)

 out:

 	mutex_unlock(lock);

 	return ret;

-}

-/**

- * adf_iov_putmsg() - send PFVF message

- * @accel_dev:  Pointer to acceleration device.

- * @msg:	Message to send

- * @vf_nr:	VF number to which the message will be sent if on PF, ignored

- *		otherwise

- *

- * Function sends a message through the PFVF channel

- *

- * Return: 0 on success, error code otherwise.

- */

-static int adf_iov_putmsg(struct adf_accel_dev *accel_dev, u32 msg, u8 vf_nr)

-{

-	u32 count = 0;

-	int ret;

-

-	do {

-		ret = __adf_iov_putmsg(accel_dev, msg, vf_nr);

-		if (ret)

-			msleep(ADF_PFVF_MSG_RETRY_DELAY);

-	} while (ret && (count++ < ADF_PFVF_MSG_MAX_RETRIES));

-

-	return ret;

+retry:

+	if (--retries) {

+		msleep(ADF_PFVF_MSG_RETRY_DELAY);

+		goto start;

+	} else {

+		ret = -EBUSY;

+		goto out;

+	}

 }

 /**

-- 

2.35.3