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 27CB01474CC; Tue, 12 Aug 2025 18:52:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755024734; cv=none; b=T2yhoMv5wf1RL8R/M+jwx5NL2XIdWbQoo6w8qA9AHdaISfOlShcoQG8fWcq7ZBlV8NgeG9SrwIrSiihNWnr2kzuQUCkNhBT+6gHA+o/JsP+eomG/jVgOdE2E3VB6Hf4FAWOC/GrQfK9k0Z8txiZJDJesBBYlI/hoCbTYXln/kPw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755024734; c=relaxed/simple; bh=0IokeVgNMoUn1DNxw+1rt3mKXIQ9Qjn7x30rlOCj9Bo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DOCMz2ChTVQnWMBLolEF0EycXDsR+4PnhpkAGPbdEP59c/EVLAzf3oEKpiklbn3YdcF41orSiTSBMlNTkWm5M86A8htcXA2EHtMcOjlddmB03Wvc5ToQ7kOtqT6QadTXZsbAjLbL5DMSmgamk5WJiN2DIuQi6G/SoO9bBkBs7og= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=tySQVlRA; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="tySQVlRA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 90A78C4CEF0; Tue, 12 Aug 2025 18:52:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1755024734; bh=0IokeVgNMoUn1DNxw+1rt3mKXIQ9Qjn7x30rlOCj9Bo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tySQVlRA3OcnhXJQ3id5CWYFK3QfHLzuPDffx+Q7Jv9T7Iy/bZ6vUpVK+HF7huvat EraLkw3do5vCNlKhuix1S+MmcAQfrGum1+xv6O0mbsS9ru7YyxBD9d/doWfcSGdByW +CDdH604wyVpF/mLAnnhBgfgRwjUDeWoV/6VCbQE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Stanley Chu , Alexandre Belloni , Sasha Levin Subject: [PATCH 6.16 462/627] i3c: master: svc: Fix npcm845 FIFO_EMPTY quirk Date: Tue, 12 Aug 2025 19:32:37 +0200 Message-ID: <20250812173439.401028636@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250812173419.303046420@linuxfoundation.org> References: <20250812173419.303046420@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stanley Chu [ Upstream commit bc4a09d8e79cadccdd505f47b01903a80bc666e7 ] In a private write transfer, the driver pre-fills the FIFO to work around the FIFO_EMPTY quirk. However, if an IBIWON event occurs, the hardware emits a NACK and the driver initiates a retry. During the retry, driver attempts to pre-fill the FIFO again if there is remaining data, but since the FIFO is already full, this leads to data loss. Check available space in FIFO to prevent overflow. Fixes: 4008a74e0f9b ("i3c: master: svc: Fix npcm845 FIFO empty issue") Signed-off-by: Stanley Chu Link: https://lore.kernel.org/r/20250730003719.1825593-1-yschu@nuvoton.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin --- drivers/i3c/master/svc-i3c-master.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c index 7e1a7cb94b43..ece563353895 100644 --- a/drivers/i3c/master/svc-i3c-master.c +++ b/drivers/i3c/master/svc-i3c-master.c @@ -104,6 +104,7 @@ #define SVC_I3C_MDATACTRL_TXTRIG_FIFO_NOT_FULL GENMASK(5, 4) #define SVC_I3C_MDATACTRL_RXTRIG_FIFO_NOT_EMPTY 0 #define SVC_I3C_MDATACTRL_RXCOUNT(x) FIELD_GET(GENMASK(28, 24), (x)) +#define SVC_I3C_MDATACTRL_TXCOUNT(x) FIELD_GET(GENMASK(20, 16), (x)) #define SVC_I3C_MDATACTRL_TXFULL BIT(30) #define SVC_I3C_MDATACTRL_RXEMPTY BIT(31) @@ -1304,14 +1305,19 @@ static int svc_i3c_master_xfer(struct svc_i3c_master *master, * FIFO start filling as soon as possible after EmitStartAddr. */ if (svc_has_quirk(master, SVC_I3C_QUIRK_FIFO_EMPTY) && !rnw && xfer_len) { - u32 end = xfer_len > SVC_I3C_FIFO_SIZE ? 0 : SVC_I3C_MWDATAB_END; - u32 len = min_t(u32, xfer_len, SVC_I3C_FIFO_SIZE); - - writesb(master->regs + SVC_I3C_MWDATAB1, out, len - 1); - /* Mark END bit if this is the last byte */ - writel(out[len - 1] | end, master->regs + SVC_I3C_MWDATAB); - xfer_len -= len; - out += len; + u32 space, end, len; + + reg = readl(master->regs + SVC_I3C_MDATACTRL); + space = SVC_I3C_FIFO_SIZE - SVC_I3C_MDATACTRL_TXCOUNT(reg); + if (space) { + end = xfer_len > space ? 0 : SVC_I3C_MWDATAB_END; + len = min_t(u32, xfer_len, space); + writesb(master->regs + SVC_I3C_MWDATAB1, out, len - 1); + /* Mark END bit if this is the last byte */ + writel(out[len - 1] | end, master->regs + SVC_I3C_MWDATAB); + xfer_len -= len; + out += len; + } } ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg, -- 2.39.5