Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:18 as permitted sender) client-ip=2620:137:e000::1:18;
From:   Alex Elder <elder@linaro.org>
To:     davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
        pabeni@redhat.com
Cc:     mka@chromium.org, evgreen@chromium.org, bjorn.andersson@linaro.org,
        quic_cpratapa@quicinc.com, quic_avuyyuru@quicinc.com,
        quic_jponduru@quicinc.com, quic_subashab@quicinc.com,
        elder@kernel.org, netdev@vger.kernel.org,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH net-next 1/8] net: ipa: make endpoint HOLB drop configurable
Date:   Fri, 20 May 2022 13:55:26 -0500
Message-Id: <20220520185533.877920-2-elder@linaro.org>
In-Reply-To: <20220520185533.877920-1-elder@linaro.org>
References: <20220520185533.877920-1-elder@linaro.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Add a new Boolean flag for RX endpoints defining whether HOLB drop
is initially enabled or disabled for the endpoint.  All existing AP
endpoints should have HOLB drop disabled.

Signed-off-by: Alex Elder <elder@linaro.org>
---
 drivers/net/ipa/ipa_endpoint.c | 8 ++++++--
 drivers/net/ipa/ipa_endpoint.h | 2 ++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c
index 0f489723689c5..3ad97fbf6884e 100644
--- a/drivers/net/ipa/ipa_endpoint.c
+++ b/drivers/net/ipa/ipa_endpoint.c
@@ -1554,8 +1554,12 @@ static void ipa_endpoint_program(struct ipa_endpoint *endpoint)
 	ipa_endpoint_init_hdr_metadata_mask(endpoint);
 	ipa_endpoint_init_mode(endpoint);
 	ipa_endpoint_init_aggr(endpoint);
-	if (!endpoint->toward_ipa)
-		ipa_endpoint_init_hol_block_disable(endpoint);
+	if (!endpoint->toward_ipa) {
+		if (endpoint->config.rx.holb_drop)
+			ipa_endpoint_init_hol_block_enable(endpoint, 0);
+		else
+			ipa_endpoint_init_hol_block_disable(endpoint);
+	}
 	ipa_endpoint_init_deaggr(endpoint);
 	ipa_endpoint_init_rsrc_grp(endpoint);
 	ipa_endpoint_init_seq(endpoint);
diff --git a/drivers/net/ipa/ipa_endpoint.h b/drivers/net/ipa/ipa_endpoint.h
index 39a12c249f66d..3ab62fb892ec6 100644
--- a/drivers/net/ipa/ipa_endpoint.h
+++ b/drivers/net/ipa/ipa_endpoint.h
@@ -60,6 +60,7 @@ struct ipa_endpoint_tx {
  * @buffer_size:	requested receive buffer size (bytes)
  * @pad_align:		power-of-2 boundary to which packet payload is aligned
  * @aggr_close_eof:	whether aggregation closes on end-of-frame
+ * @holb_drop:		whether to drop packets to avoid head-of-line blocking
  *
  * With each packet it transfers, the IPA hardware can perform certain
  * transformations of its packet data.  One of these is adding pad bytes
@@ -74,6 +75,7 @@ struct ipa_endpoint_rx {
 	u32 buffer_size;
 	u32 pad_align;
 	bool aggr_close_eof;
+	bool holb_drop;
 };
 
 /**
-- 
2.32.0