From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 45A11275864 for ; Fri, 6 Feb 2026 15:03:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770390187; cv=none; b=ccBDtRYhzR2zcOfPXVuoH32YXAXWRNFaUJKZnokAQhbdlpnaMX3E+vgO0pFFNVIrjmv5sYbnT0XFYnzikgQ67GPNU/5pY+b7u1hWtvlwACzCN98FuRDfgpAs/wkpX87UQcQi8jGFx7hTCXNkkdxUhTiiDrBAPPLgIU3KXAi1gEI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770390187; c=relaxed/simple; bh=LB7QDEsMXgPCxCjTIXwHVncfd/5iivLKZH1PdJOqVjU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=rCIz8t97If3u58nwLaK0o0XPQYuTV5zgN+sb8cuhVVUhlD07GNWORWWMLmT5jyM86WrHCNFiL8BcoMz3cFU9oRWTGWXkq8wAfJISefQAzxewxjkmTrEmG1K9feOd1jMNzmX2K7jATk+IrxrGyb/DJZjgLbjfGyF2m39cm8rvSE4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=FTHh7HtV; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="FTHh7HtV" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1770390186; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1i6cAHTv7DBd9mv/VZP++loTThVeud67POkhWzDkRRM=; b=FTHh7HtVfq8LTb5KunxlFb9tZM0GsVF84Lg36VkvVt730koGdpTG3Co+jwcaN0/XFzbAS9 knWxB0gYBOrNm+3iIBbvEZOl4dLuSvw768C4v55DIkdiI1e3Xd0LvCept3w9/9V7/Nb7JM I9QUZjbplJ5CIq9hYvjaZULhP0T8uwc= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-527-jXqXJ1jDNOCmbzcpKl7krA-1; Fri, 06 Feb 2026 10:03:02 -0500 X-MC-Unique: jXqXJ1jDNOCmbzcpKl7krA-1 X-Mimecast-MFC-AGG-ID: jXqXJ1jDNOCmbzcpKl7krA_1770390181 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 5EB581955F21; Fri, 6 Feb 2026 15:03:01 +0000 (UTC) Received: from [10.44.34.88] (unknown [10.44.34.88]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 9B12A1800465; Fri, 6 Feb 2026 15:02:59 +0000 (UTC) Message-ID: Date: Fri, 6 Feb 2026 16:02:58 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net] dpll: zl3073x: Fix output pin phase adjustment sign To: Vadim Fedorenko , netdev@vger.kernel.org Cc: Prathosh Satish , Arkadiusz Kubalewski , Jiri Pirko , linux-kernel@vger.kernel.org References: <20260205181055.129768-1-ivecera@redhat.com> Content-Language: en-US From: Ivan Vecera In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 On 2/6/26 3:04 PM, Vadim Fedorenko wrote: > On 05/02/2026 18:10, Ivan Vecera wrote: >> The output pin phase adjustment functions incorrectly negate the phase >> compensation value. >> >> Per the ZL3073x datasheet, the output phase compensation register is >> simply a signed two's complement integer where: >>   - Positive values move the phase later in time >>   - Negative values move the phase earlier in time >> >> No negation is required. The erroneous negation caused phase adjustments >> to be applied in the wrong direction. >> >> Note that input pin phase adjustment correctly uses negation because the >> hardware has an inverted convention for input references (positive moves >> phase earlier, negative moves phase later). > > Is it common for DPLLs to act this way? I don't now if this is common for DPLLs but for ZL3073x family chips the datasheet says: ref_phase_offset_compensation: ============================== Phase offset compensation for references. The value is specified as a signed two's complement, in units of ps. A positive value moves the phase of any DPLL that locks to this reference earlier in time (more to the left on a scope). A negative value moves the phase of any DPLL that locks to this reference later in time (more to the right on a scope). output_phase_compensation: ========================== Output phase shift, expressed in 1/2 synth clock cycles. Two-complement signed integer. A positive value moves the phase of the output later in time (more to the right on a scope). A negative value moves the phase earlier in time (more to the left on a scope). So for input pins the value must be negated, while for output pins it is not. >> >> Fixes: 6287262f761e ("dpll: zl3073x: Add support to adjust phase") >> Signed-off-by: Ivan Vecera > > Anyways, with datasheet info being correctly read, the change LGTM > Reviewed-by: Vadim Fedorenko > Thanks, Ivan