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From:   Oded Gabbay <ogabbay@kernel.org>
To:     linux-kernel@vger.kernel.org
Cc:     Ofir Bitton <obitton@habana.ai>
Subject: [PATCH 7/9] habanalabs/gaudi: allow device acquire while in debug mode
Date:   Wed, 28 Dec 2022 18:07:21 +0200
Message-Id: <20221228160723.387-7-ogabbay@kernel.org>
In-Reply-To: <20221228160723.387-1-ogabbay@kernel.org>
References: <20221228160723.387-1-ogabbay@kernel.org>
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From: Ofir Bitton <obitton@habana.ai>

During device acquire, the driver is using a QMAN for clearing some
registers. In order to avoid internal races, the driver verifies
the device is idle before submitting the register clear job.

This check introduces an issue, as debug mode will cause the device
to be non-idle which will lead to device acquire failure.

In order to overcome this issue we can entirely remove the idle
check as the driver is using the QMAN only when there is no active
context.

Signed-off-by: Ofir Bitton <obitton@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
---
 drivers/accel/habanalabs/gaudi/gaudi.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/drivers/accel/habanalabs/gaudi/gaudi.c b/drivers/accel/habanalabs/gaudi/gaudi.c
index 13f9e6c0cd90..733916f38752 100644
--- a/drivers/accel/habanalabs/gaudi/gaudi.c
+++ b/drivers/accel/habanalabs/gaudi/gaudi.c
@@ -6434,12 +6434,6 @@ static int gaudi_send_job_on_qman0(struct hl_device *hdev,
 	else
 		timeout = HL_DEVICE_TIMEOUT_USEC;
 
-	if (!hdev->asic_funcs->is_device_idle(hdev, NULL, 0, NULL)) {
-		dev_err_ratelimited(hdev->dev,
-			"Can't send driver job on QMAN0 because the device is not idle\n");
-		return -EBUSY;
-	}
-
 	fence_ptr = hl_asic_dma_pool_zalloc(hdev, 4, GFP_KERNEL, &fence_dma_addr);
 	if (!fence_ptr) {
 		dev_err(hdev->dev,
-- 
2.34.1