From patchwork Tue Sep 5 23:26:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arkadiusz Kubalewski X-Patchwork-Id: 13375178 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 D9013101F7 for ; Tue, 5 Sep 2023 23:28:54 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 84B259E; Tue, 5 Sep 2023 16:28:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1693956533; x=1725492533; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=F2CQJwTeN0GzfUnZLBPf8lFc7IkGO9Ewx87bLeroNy4=; b=Ltzwv8dQf7NScRtw+KGFww88CwqZ+zvwguLYeoXwGxOHKTm293M2fpTV /wLHU6BUNi98itSQs6HxknEaMPQR/cYGgGt1BJS942R8JX8PssOukVVeA n81jo0ewh6YdnB48Kjh545UKodYPm0mByo2SMQuJMj4EhuEKFPMTyY9Z3 SD/hecwRg7gcevolpbl5hQ4H46SsxX4OBcOdcEhDz3h0YS3nhQCfFb6Fm Gc3LnwFLn9tQdcTGzM6b1soO6ORA3p8fOJvF6GYL7n4uniNiznDzNT9zQ PTje6HX7mZaRVhpZgWNgfI3soC6hZSfP2kY3Gqa9yWlU5GYRhC8C/2uWd Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10824"; a="379643898" X-IronPort-AV: E=Sophos;i="6.02,230,1688454000"; d="scan'208";a="379643898" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Sep 2023 16:28:53 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10824"; a="744448402" X-IronPort-AV: E=Sophos;i="6.02,230,1688454000"; d="scan'208";a="744448402" Received: from amlin-018-114.igk.intel.com ([10.102.18.114]) by fmsmga007.fm.intel.com with ESMTP; 05 Sep 2023 16:28:50 -0700 From: Arkadiusz Kubalewski To: kuba@kernel.org, jiri@resnulli.us, jonathan.lemon@gmail.com, pabeni@redhat.com, vadim.fedorenko@linux.dev Cc: linux-arm-kernel@lists.infradead.org, poros@redhat.com, mschmidt@redhat.com, netdev@vger.kernel.org, linux-clk@vger.kernel.org, bvanassche@acm.org, intel-wired-lan@lists.osuosl.org, Arkadiusz Kubalewski Subject: [PATCH net-next 1/4] dpll: docs: add support for pin signal phase offset/adjust Date: Wed, 6 Sep 2023 01:26:07 +0200 Message-Id: <20230905232610.1403647-2-arkadiusz.kubalewski@intel.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20230905232610.1403647-1-arkadiusz.kubalewski@intel.com> References: <20230905232610.1403647-1-arkadiusz.kubalewski@intel.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, RCVD_IN_DNSWL_BLOCKED,RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: kuba@kernel.org Add documentation on: - measurment of phase of signal between pin and dpll - adjustment of pin signal phase Signed-off-by: Arkadiusz Kubalewski --- Documentation/driver-api/dpll.rst | 53 ++++++++++++++++++++++++++++++- 1 file changed, 52 insertions(+), 1 deletion(-) diff --git a/Documentation/driver-api/dpll.rst b/Documentation/driver-api/dpll.rst index bb52f1b8c0be..59634a3513bd 100644 --- a/Documentation/driver-api/dpll.rst +++ b/Documentation/driver-api/dpll.rst @@ -173,6 +173,47 @@ in order to configure active input of a MUX-type pin, the user needs to request desired pin state of the child pin on the parent pin, as described in the ``MUX-type pins`` chapter. +Phase offset measurement and adjustment +======================================== + +Device may provide ability to measure a phase difference between signals +on a pin and its parent dpll device. If pin-dpll phase offset measurement +is supported, it shall be provided with ``DPLL_A_PIN_PHASE_OFFSET`` +attribute for each parent dpll device. + +Device may also provide ability to adjust a signal phase on a pin. +If pin phase adjustment is supported, minimal and maximal values that pin +handle shall be provide to the user on ``DPLL_CMD_PIN_GET`` respond +with ``DPLL_A_PIN_PHASE_ADJUST_MIN`` and ``DPLL_A_PIN_PHASE_ADJUST_MAX`` +attributes. Configured phase adjust value is provided with +``DPLL_A_PIN_PHASE_ADJUST`` attribute of a pin, and value change can be +requested with the same attribute with ``DPLL_CMD_PIN_SET`` command. + + =============================== ====================================== + ``DPLL_A_PIN_ID`` configured pin id + ``DPLL_A_PIN_PHASE_ADJUST_MIN`` attr minimum value of phase adjustment + ``DPLL_A_PIN_PHASE_ADJUST_MAX`` attr maximum value of phase adjustment + ``DPLL_A_PIN_PHASE_ADJUST`` attr configured value of phase + adjustment on parent dpll device + ``DPLL_A_PIN_PARENT_DEVICE`` nested attribute for requesting + configuration on given parent dpll + device + ``DPLL_A_PIN_PARENT_ID`` parent dpll device id + ``DPLL_A_PIN_PHASE_OFFSET`` attr measured phase difference + between a pin and parent dpll device + =============================== ====================================== + +All phase related values are provided in pico seconds, which represents +time differnece between signals phase. The negative value means that +phase of signal on pin is earlier in time than dpll's signal. Positive +value means that phase of signal on pin is later in time than signal of +a dpll. + +Phase adjust (also min and max) values are integers, but measured phase +offset values are fractional with 3-digit decimal places and shell be +divided with ``DPLL_PIN_PHASE_OFFSET_DIVIDER`` to get integer part and +modulo divided to get fractional part. + Configuration commands group ============================ @@ -263,6 +304,12 @@ according to attribute purpose. frequencies ``DPLL_A_PIN_ANY_FREQUENCY_MIN`` attr minimum value of frequency ``DPLL_A_PIN_ANY_FREQUENCY_MAX`` attr maximum value of frequency + ``DPLL_A_PIN_PHASE_ADJUST_MIN`` attr minimum value of phase + adjustment + ``DPLL_A_PIN_PHASE_ADJUST_MAX`` attr maximum value of phase + adjustment + ``DPLL_A_PIN_PHASE_ADJUST`` attr configured value of phase + adjustment on parent device ``DPLL_A_PIN_PARENT_DEVICE`` nested attr for each parent device the pin is connected with ``DPLL_A_PIN_PARENT_ID`` attr parent dpll device id @@ -270,8 +317,10 @@ according to attribute purpose. dpll device ``DPLL_A_PIN_STATE`` attr state of pin on the parent dpll device - ``DPLL_A_PIN_DIRECTION`` attr direction of a pin on the + ``DPLL_A_PIN_DIRECTION`` attr direction of a pin on the parent dpll device + ``DPLL_A_PIN_PHASE_OFFSET`` attr measured phase difference + between a pin and parent dpll ``DPLL_A_PIN_PARENT_PIN`` nested attr for each parent pin the pin is connected with ``DPLL_A_PIN_PARENT_ID`` attr parent pin id @@ -284,6 +333,8 @@ according to attribute purpose. ``DPLL_CMD_PIN_SET`` command to set pins configuration ``DPLL_A_PIN_ID`` attr unique a pin ID ``DPLL_A_PIN_FREQUENCY`` attr requested frequency of a pin + ``DPLL_A_PIN_PHASE_ADJUST`` attr requested value of phase + adjustment on parent device ``DPLL_A_PIN_PARENT_DEVICE`` nested attr for each parent dpll device configuration request ``DPLL_A_PIN_PARENT_ID`` attr parent dpll device id