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 E27A2189BA5; Wed, 25 Sep 2024 12:43:18 +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=1727268199; cv=none; b=ngGKQobeS/pOl9kONVdps6rZDDVfTHTSqXh4NAmL9zY7AUidDgiie73BmyF4zZK4liL4rTKURWibx+wtyhwXBiLsIFmdH9Q6tmRm2DH5fnJG+dw12hxD+UXX0Uz5RNukWrBnnSy5tcDaG/wWSfYIDINXSQDc+/PH4g99FBUvvro= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727268199; c=relaxed/simple; bh=55DEg7P/EG6eoblczRYM9wqjNyVJh5awwba1Zdov68c=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Pd1Xb1f/FzexrPIR+vgC/KYu4jxy4UZ31SNMOgIUH6q/YXMfTolMqznS3HoVgizDGIza5xxxaR6O0mo0ezfk2iEa87Qmq3EllR2DX3whbFpxHlxKhZw+4HBgIpNCLpuNVWCA6xPk8rN+tJopxeTUvofDuDpzNSN8F9OEJONNjr8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TlfGlTkM; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TlfGlTkM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 57CC0C4CEC3; Wed, 25 Sep 2024 12:43:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1727268198; bh=55DEg7P/EG6eoblczRYM9wqjNyVJh5awwba1Zdov68c=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TlfGlTkMqanK0tCToFOxBbWlKErG/Lr1iUgou17ij9FKgnUlMIpyBkMkcRZ0gFARu 4sCBqXLddMEyLmij0JS7fMrh9MP5YM/zPfzX4vQbKmLcr+QF3Mu7I+Kso1DLP2KQFq rHGw6ViiKqpqN0QxELepFG4YfVhfOKkmXCOTM1/i6W8xyCYMkY2E0/x8XyHDpGEALz 3V1JVOWZODosDnMu76b7sud3yDnQ3t/hTs020j3mwjmlyUUGGrrtCSKdh2Kr5YGQuy 6drE0vy/DzpCtdnhzfsjCHlsjXuXTMG4vUm0kjbU3QGddaOEIE/yX1rab3D/ZGmFgU Jm9iWJRN/201Q== Date: Wed, 25 Sep 2024 20:43:10 +0800 From: Peter Chen To: Xu Yang Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, imx@lists.linux.dev, jun.li@nxp.com Subject: Re: [PATCH v2 2/3] usb: chipidea: udc: improve dTD link logic Message-ID: <20240925124310.GB417263@nchen-desktop> References: <20240920094056.2680590-1-xu.yang_2@nxp.com> <20240920094056.2680590-2-xu.yang_2@nxp.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240920094056.2680590-2-xu.yang_2@nxp.com> On 24-09-20 17:40:55, Xu Yang wrote: > Currently, ATDTW semaphore is used to safety link new dTD to dQH. But this > code has a bug when the endpoint is already in error before polling ATDTW > or just met error during polling ATDTW. In that cases, ATDTW will never > turn to 1 and the cpu will busy loop there. > > When the endpoint met error, ENDPTSTAT will be cleared by HW. Therefore, > ENDPTSTAT should also be considered during this process. In case of > endpoint error, the current dTD should not be pushed to the head of dQH > since some dTDs may be still not executed. Therefore, the link logic is > also improved accordingly. > > Fixes: 26c696c678c4 ("USB: Chipidea: rename struct ci13xxx variables from udc to ci") > Cc: stable@vger.kernel.org > Signed-off-by: Xu Yang The same comment, do not cc stable tree, not sure if it will affect others. Peter > > --- > Changes in v2: > - modify comments > - fix kernel test robot build warning by using cpu_to_le32 > - add fix tag and cc stable > --- > drivers/usb/chipidea/udc.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c > index e0092c735a75..c0b8745234c6 100644 > --- a/drivers/usb/chipidea/udc.c > +++ b/drivers/usb/chipidea/udc.c > @@ -752,10 +752,17 @@ static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq) > do { > hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW); > tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n)); > - } while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW)); > + } while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW) && tmp_stat); > hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0); > if (tmp_stat) > goto done; > + > + /* OP_ENDPTSTAT will be clear by HW when the endpoint met > + * err. This dTD don't push to dQH if current dTD point is > + * not the last one in previous request. > + */ > + if (hwep->qh.ptr->curr != cpu_to_le32(prevlastnode->dma)) > + goto done; > } > > /* QH configuration */ > -- > 2.34.1 >