From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1C2C6606A320 for ; Tue, 10 Nov 2026 15:25:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=gHdYxxqO; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=NBgLUCYw DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Unsubscribe-Post: List-Owner; bh=ZxHsaK8/Nc8cB5gd1xWnchJme5sokD+PiLu0QduYwF0=; b=gHdYxxqOaEI/3p fUABl/lq7vJ5OJCQnUk+tYIFU5cj0Ow7tKlU7IRk2ncIPtHmPslQyuA7jm1wST9uJBpsY+kpNlAWS VWRHtfegT3WXTgvhPQN3Bq54BIB3f1oQfIlZNuSJLEebVyZ25+Z351Nj8dDsetpRnSW/2n05aQPkq I3p4/gzX51QUmRohaJB+1irxx0IvrWpm7LQ5uLRCpQfTS9raVHxRj94VENj+4dUOfl3buhLe+BlLq mjwf1HWdib+ZmLgTQj5ya8SanU63wTPf1ZQrRgh9VpjGG2bVNK5zsBxmmtDNTwp/e4k0tYGqvZ1T7 7ExsnxDUTKLCcttHbgbA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xQnij-00000004MI2-0CZG; Tue, 10 Nov 2026 15:25:13 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xQnif-00000004MGy-2PcQ for linux-arm-kernel@lists.infradead.org; Tue, 10 Nov 2026 15:25:10 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 514F01477; Tue, 10 Nov 2026 07:25:05 -0800 (PST) Received: from [10.2.197.99] (ewhatever.cambridge.arm.com [10.2.197.99]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9EB393F85F; Tue, 10 Nov 2026 07:25:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1794324308; bh=KyJGfKTqMKWcdpGq28AE4r7i+T5cmpj/njBVE62d1bE=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=NBgLUCYwVxUQk7+f5b/WN0ZoVuVFBcBpq3nkb/N8ILa0LarygzCPSmM+SmsZ+QfLY P9ODmXUjwKufv2M6yQernOgA9xob4TypGD4z0do69DKUlNNZCfmA1lLDP8htII36Ba MyO7xPuLNSymRfurSDCJhAFBi3R/JT2U0iGe7rZc= Message-ID: <83fe9c8a-c2d1-4859-b17c-9c350609d1ec@arm.com> Date: Tue, 10 Nov 2026 15:25:04 +0000 X-Archived-By: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 09/23] coresight: trbe: Clear TRBSR status at stop sites To: Leo Yan Cc: Mike Leach , James Clark , Alexander Shishkin , Anshuman Khandual , Tamas Petz , Tamas Zsoldos , Suyash Mahar , Amir Ayupov , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, coresight@lists.linaro.org References: <20261016-trbe_enable_disable_irq_handle_refactor-v2-0-3f57cf3199b1@arm.com> <20261016-trbe_enable_disable_irq_handle_refactor-v2-9-3f57cf3199b1@arm.com> <20261110084804.GZ9176@e132581.arm.com> Content-Language: en-US From: Suzuki K Poulose In-Reply-To: <20261110084804.GZ9176@e132581.arm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261110_072509_705636_1A04E402 X-CRM114-Status: GOOD ( 15.00 ) X-Spam-Score: -4.4 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-17.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On 10/11/2026 08:48, Leo Yan wrote: > On Mon, Nov 09, 2026 at 10:51:30PM +0000, Suzuki K Poulose wrote: >> On 16/10/2026 17:55, Leo Yan wrote: >>> TRBSR_EL1 records the status of the buffer that just stopped. Clearing >>> it in trbe_enable_hw() postpones cleanup until another run starts. If >>> AUX output cannot restart, for example when AUX space is exhausted, >>> that clear never executes. Clear the status in arm_trbe_disable() >>> after disabling TRBE instead. >>> >>> trbe_handle_overflow() can start the next run without calling >>> arm_trbe_disable(). Clear the stopped buffer's syndrome and status bits >>> while TRBE is disabled, before attempting the AUX restart. This also >>> leaves the status clean when the restart fails. >>> >>> Signed-off-by: Leo Yan >>> --- >>> drivers/hwtracing/coresight/coresight-trbe.c | 10 +++++++++- >>> 1 file changed, 9 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c >>> index 26e7554d6bdd31f8a55a8bc3a7b6d4c49b984b9b..dd9c9330bb0c739795f300dafc6ce34e72fbf280 100644 >>> --- a/drivers/hwtracing/coresight/coresight-trbe.c >>> +++ b/drivers/hwtracing/coresight/coresight-trbe.c >>> @@ -655,7 +655,6 @@ static void trbe_enable_hw(struct trbe_buf *buf) >>> WARN_ON(buf->trbe_hw_base < buf->trbe_base); >>> WARN_ON(buf->trbe_write < buf->trbe_hw_base); >>> WARN_ON(buf->trbe_write >= buf->trbe_limit); >>> - clr_trbe_status(); >> >> TRBSR_ELx is UNKNOWN at reset and if we don't clear it at probe time, we >> endup running the first session with unknown values. It is safer to >> clear this at enable_hw. > > This is incorrect. trbe_reset_local() is called locally on each CPU to > clear TRBSR_ELx, it has been guaranteed when the first session starts. > Ah, you're right. Ignore the noise Cheers Suzuki > Thanks, > Leo