From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E33721F955 for ; Tue, 1 Aug 2023 09:25:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 664F0C433C8; Tue, 1 Aug 2023 09:25:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1690881902; bh=HYjfseIgSeINR8T61KEHTcbWwlSO+jxhNtFATCB3IPI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uKLX7wOmhsH3VUWNB/S3VgDfvsy+CQ9nlCYR8A8S3+zgS6xwyXAYZkiR4YtXqtauj k/kq94pbp6rvlcWy14i/yX5utKWRO/ANAM23XRO1rP0h1Xu572OXpH85TUYma185AO mSmfqpvqCxRmG1meKLEy/0Tx60NV8r2o0kCxyifo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Vincent Whitchurch , Simon Horman , Paolo Abeni , Sasha Levin Subject: [PATCH 5.15 070/155] net: stmmac: Apply redundant write work around on 4.xx too Date: Tue, 1 Aug 2023 11:19:42 +0200 Message-ID: <20230801091912.674610940@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230801091910.165050260@linuxfoundation.org> References: <20230801091910.165050260@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Vincent Whitchurch [ Upstream commit 284779dbf4e98753458708783af8c35630674a21 ] commit a3a57bf07de23fe1ff779e0fdf710aa581c3ff73 ("net: stmmac: work around sporadic tx issue on link-up") worked around a problem with TX sometimes not working after a link-up by avoiding a redundant write to MAC_CTRL_REG (aka GMAC_CONFIG), since the IP appeared to have problems with handling multiple writes to that register in some cases. That commit however only added the work around to dwmac_lib.c (apart from the common code in stmmac_main.c), but my systems with version 4.21a of the IP exhibit the same problem, so add the work around to dwmac4_lib.c too. Fixes: a3a57bf07de2 ("net: stmmac: work around sporadic tx issue on link-up") Signed-off-by: Vincent Whitchurch Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/20230721-stmmac-tx-workaround-v1-1-9411cbd5ee07@axis.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- drivers/net/ethernet/stmicro/stmmac/dwmac4_lib.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_lib.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_lib.c index 9292a1fab7d32..7011c08d2e012 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_lib.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_lib.c @@ -207,13 +207,15 @@ void stmmac_dwmac4_set_mac_addr(void __iomem *ioaddr, u8 addr[6], void stmmac_dwmac4_set_mac(void __iomem *ioaddr, bool enable) { u32 value = readl(ioaddr + GMAC_CONFIG); + u32 old_val = value; if (enable) value |= GMAC_CONFIG_RE | GMAC_CONFIG_TE; else value &= ~(GMAC_CONFIG_TE | GMAC_CONFIG_RE); - writel(value, ioaddr + GMAC_CONFIG); + if (value != old_val) + writel(value, ioaddr + GMAC_CONFIG); } void stmmac_dwmac4_get_mac_addr(void __iomem *ioaddr, unsigned char *addr, -- 2.39.2