From:   Sai Krishna <saikrishnag@marvell.com>
To:     <davem@davemloft.net>, <edumazet@google.com>, <kuba@kernel.org>,
        <pabeni@redhat.com>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <sgoutham@marvell.com>,
        <gakula@marvell.com>
CC:     Sai Krishna <saikrishnag@marvell.com>
Subject: [net-next PATCH] octeontx2-af: Add NIX Errata workaround on CN10K silicon
Date:   Fri, 17 Feb 2023 11:21:12 +0530
Message-ID: <20230217055112.1248842-1-saikrishnag@marvell.com>
MIME-Version: 1.0
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Precedence: bulk

From: Geetha sowjanya <gakula@marvell.com>

This patch adds workaround for below 2 HW erratas

1. Due to improper clock gating, NIXRX may free the same
NPA buffer multiple times.. to avoid this, always enable
NIX RX conditional clock.

2. NIX FIFO does not get initialized on reset, if the SMQ
flush is triggered before the first packet is processed, it
will lead to undefined state. The workaround to perform SMQ
flush only if packet count is non-zero in MDQ.

Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: Sunil Kovvuri Goutham <sgoutham@marvell.com>
Signed-off-by: Sai Krishna <saikrishnag@marvell.com>
---
 .../net/ethernet/marvell/octeontx2/af/rvu.h    |  3 +++
 .../ethernet/marvell/octeontx2/af/rvu_cn10k.c  | 18 ++++++++++++++++++
 .../ethernet/marvell/octeontx2/af/rvu_nix.c    | 10 ++++++++++
 .../ethernet/marvell/octeontx2/af/rvu_reg.h    |  2 ++
 4 files changed, 33 insertions(+)

diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu.h b/drivers/net/ethernet/marvell/octeontx2/af/rvu.h
index 5eea2b6cf6bd..389663a13d1d 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu.h
+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu.h
@@ -888,6 +888,9 @@ int rvu_cpt_init(struct rvu *rvu);
 int rvu_set_channels_base(struct rvu *rvu);
 void rvu_program_channels(struct rvu *rvu);
 
+/* CN10K NIX */
+void rvu_nix_block_cn10k_init(struct rvu *rvu, struct nix_hw *nix_hw);
+
 /* CN10K RVU - LMT*/
 void rvu_reset_lmt_map_tbl(struct rvu *rvu, u16 pcifunc);
 
diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu_cn10k.c b/drivers/net/ethernet/marvell/octeontx2/af/rvu_cn10k.c
index 7dbbc115cde4..4ad9ff025c96 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu_cn10k.c
+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu_cn10k.c
@@ -538,3 +538,21 @@ void rvu_program_channels(struct rvu *rvu)
 	rvu_lbk_set_channels(rvu);
 	rvu_rpm_set_channels(rvu);
 }
+
+void rvu_nix_block_cn10k_init(struct rvu *rvu, struct nix_hw *nix_hw)
+{
+	int blkaddr = nix_hw->blkaddr;
+	u64 cfg;
+
+	/* Set AF vWQE timer interval to a LF configurable range of
+	 * 6.4us to 1.632ms.
+	 */
+	rvu_write64(rvu, blkaddr, NIX_AF_VWQE_TIMER, 0x3FULL);
+
+	/* Enable NIX RX stream and global conditional clock to
+	 * avoild multiple free of NPA buffers.
+	 */
+	cfg = rvu_read64(rvu, blkaddr, NIX_AF_CFG);
+	cfg |= BIT_ULL(1) | BIT_ULL(2);
+	rvu_write64(rvu, blkaddr, NIX_AF_CFG, cfg);
+}
diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu_nix.c b/drivers/net/ethernet/marvell/octeontx2/af/rvu_nix.c
index 89e94569e74c..26e639e57dae 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu_nix.c
+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu_nix.c
@@ -2058,6 +2058,13 @@ static int nix_smq_flush(struct rvu *rvu, int blkaddr,
 	int err, restore_tx_en = 0;
 	u64 cfg;
 
+	if (!is_rvu_otx2(rvu)) {
+		/* Skip SMQ flush if pkt count is zero */
+		cfg = rvu_read64(rvu, blkaddr, NIX_AF_MDQX_IN_MD_COUNT(smq));
+		if (!cfg)
+			return 0;
+	}
+
 	/* enable cgx tx if disabled */
 	if (is_pf_cgxmapped(rvu, pf)) {
 		rvu_get_cgx_lmac_id(rvu->pf2cgxlmac_map[pf], &cgx_id, &lmac_id);
@@ -4309,6 +4316,9 @@ static int rvu_nix_block_init(struct rvu *rvu, struct nix_hw *nix_hw)
 
 	rvu_write64(rvu, blkaddr, NIX_AF_SEB_CFG, cfg);
 
+	if (!is_rvu_otx2(rvu))
+		rvu_nix_block_cn10k_init(rvu, nix_hw);
+
 	if (is_block_implemented(hw, blkaddr)) {
 		err = nix_setup_txschq(rvu, nix_hw, blkaddr);
 		if (err)
diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu_reg.h b/drivers/net/ethernet/marvell/octeontx2/af/rvu_reg.h
index 5437bd20c719..1729b22580ce 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu_reg.h
+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu_reg.h
@@ -189,6 +189,7 @@
 #define NIX_AF_RX_CFG			(0x00D0)
 #define NIX_AF_AVG_DELAY		(0x00E0)
 #define NIX_AF_CINT_DELAY		(0x00F0)
+#define NIX_AF_VWQE_TIMER		(0x00F8)
 #define NIX_AF_RX_MCAST_BASE		(0x0100)
 #define NIX_AF_RX_MCAST_CFG		(0x0110)
 #define NIX_AF_RX_MCAST_BUF_BASE	(0x0120)
@@ -426,6 +427,7 @@
 #define NIX_AF_RX_NPC_MIRROR_DROP	(0x4730)
 #define NIX_AF_RX_ACTIVE_CYCLES_PCX(a)	(0x4800 | (a) << 16)
 #define NIX_AF_LINKX_CFG(a)		(0x4010 | (a) << 17)
+#define NIX_AF_MDQX_IN_MD_COUNT(a)	(0x14e0 | (a) << 16)
 
 #define NIX_PRIV_AF_INT_CFG		(0x8000000)
 #define NIX_PRIV_LFX_CFG		(0x8000010)
-- 
2.25.1