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From:   Jayesh Choudhary <j-choudhary@ti.com>
To:     <vkoul@kernel.org>, <peter.ujfalusi@gmail.com>
CC:     <vaishnav.a@ti.com>, <dmaengine@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <j-choudhary@ti.com>
Subject: [PATCH] dmaengine: ti: k3-udma: Do conditional decrement of UDMA_CHAN_RT_PEER_BCNT_REG
Date:   Mon, 28 Nov 2022 14:20:05 +0530
Message-ID: <20221128085005.489964-1-j-choudhary@ti.com>
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PSIL_EP_NATIVE endpoints may not have PEER registers for BCNT and thus
udma_decrement_byte_counters() should not try to decrement these counters.
This fixes the issue of crypto IPERF testing where the client side (EVM)
hangs without transfer of packets to the server side, seen since this
function was added.

Fixes: 7c94dcfa8fcf ("dmaengine: ti: k3-udma: Reset UDMA_CHAN_RT byte counters to prevent overflow")
Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
---
 drivers/dma/ti/k3-udma.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c
index ce8b80bb34d7..4c62274e0b33 100644
--- a/drivers/dma/ti/k3-udma.c
+++ b/drivers/dma/ti/k3-udma.c
@@ -762,11 +762,12 @@ static void udma_decrement_byte_counters(struct udma_chan *uc, u32 val)
 	if (uc->desc->dir == DMA_DEV_TO_MEM) {
 		udma_rchanrt_write(uc, UDMA_CHAN_RT_BCNT_REG, val);
 		udma_rchanrt_write(uc, UDMA_CHAN_RT_SBCNT_REG, val);
-		udma_rchanrt_write(uc, UDMA_CHAN_RT_PEER_BCNT_REG, val);
+		if (uc->config.ep_type != PSIL_EP_NATIVE)
+			udma_rchanrt_write(uc, UDMA_CHAN_RT_PEER_BCNT_REG, val);
 	} else {
 		udma_tchanrt_write(uc, UDMA_CHAN_RT_BCNT_REG, val);
 		udma_tchanrt_write(uc, UDMA_CHAN_RT_SBCNT_REG, val);
-		if (!uc->bchan)
+		if (!uc->bchan && uc->config.ep_type != PSIL_EP_NATIVE)
 			udma_tchanrt_write(uc, UDMA_CHAN_RT_PEER_BCNT_REG, val);
 	}
 }
-- 
2.25.1