From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx01.omp.ru (mx01.omp.ru [90.154.21.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2EF15DF42; Mon, 1 Jan 2024 20:49:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=omp.ru Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=omp.ru Received: from [192.168.1.104] (178.176.77.76) by msexch01.omp.ru (10.188.4.12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.1258.12; Mon, 1 Jan 2024 23:49:07 +0300 Subject: Re: [PATCH net v2 1/1] net: ravb: Wait for operation mode to be applied To: claudiu beznea , , , , , , , CC: , , , Claudiu Beznea References: <20231222113552.2049088-1-claudiu.beznea.uj@bp.renesas.com> <20231222113552.2049088-2-claudiu.beznea.uj@bp.renesas.com> <98efc508-c431-2509-5799-96decc124136@omp.ru> <9ebf96fb-c07a-8269-e5cd-0e71110941dd@omp.ru> From: Sergey Shtylyov Organization: Open Mobile Platform Message-ID: Date: Mon, 1 Jan 2024 23:49:06 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-ClientProxiedBy: msexch01.omp.ru (10.188.4.12) To msexch01.omp.ru (10.188.4.12) X-KSE-ServerInfo: msexch01.omp.ru, 9 X-KSE-AntiSpam-Interceptor-Info: scan successful X-KSE-AntiSpam-Version: 6.1.0, Database issued on: 01/01/2024 20:37:31 X-KSE-AntiSpam-Status: KAS_STATUS_NOT_DETECTED X-KSE-AntiSpam-Method: none X-KSE-AntiSpam-Rate: 59 X-KSE-AntiSpam-Info: Lua profiles 182447 [Dec 31 2023] X-KSE-AntiSpam-Info: Version: 6.1.0.3 X-KSE-AntiSpam-Info: Envelope from: s.shtylyov@omp.ru X-KSE-AntiSpam-Info: LuaCore: 7 0.3.7 6d6bf5bd8eea7373134f756a2fd73e9456bb7d1a X-KSE-AntiSpam-Info: {rep_avail} X-KSE-AntiSpam-Info: {Tracking_from_domain_doesnt_match_to} X-KSE-AntiSpam-Info: {relay has no DNS name} X-KSE-AntiSpam-Info: {SMTP from is not routable} X-KSE-AntiSpam-Info: {Found in DNSBL: 178.176.77.76 in (user) b.barracudacentral.org} X-KSE-AntiSpam-Info: 127.0.0.199:7.1.2;d41d8cd98f00b204e9800998ecf8427e.com:7.1.1;omp.ru:7.1.1 X-KSE-AntiSpam-Info: ApMailHostAddress: 178.176.77.76 X-KSE-AntiSpam-Info: {DNS response errors} X-KSE-AntiSpam-Info: Rate: 59 X-KSE-AntiSpam-Info: Status: not_detected X-KSE-AntiSpam-Info: Method: none X-KSE-AntiSpam-Info: Auth:dmarc=temperror header.from=omp.ru;spf=temperror smtp.mailfrom=omp.ru;dkim=none X-KSE-Antiphishing-Info: Clean X-KSE-Antiphishing-ScanningType: Heuristic X-KSE-Antiphishing-Method: None X-KSE-Antiphishing-Bases: 01/01/2024 20:41:00 X-KSE-Antivirus-Interceptor-Info: scan successful X-KSE-Antivirus-Info: Clean, bases: 1/1/2024 5:15:00 PM X-KSE-Attachment-Filter-Triggered-Rules: Clean X-KSE-Attachment-Filter-Triggered-Filters: Clean X-KSE-BulkMessagesFiltering-Scan-Result: InTheLimit On 12/29/23 6:07 PM, claudiu beznea wrote: [...] >>>>> From: Claudiu Beznea >>>>> >>>>> CSR.OPS bits specify the current operating mode and (according to >>>>> documentation) they are updated by HW when the operating mode change >>>>> request is processed. To comply with this check CSR.OPS before proceeding. >>>>> >>>>> Commit introduces ravb_set_opmode() that does all the necessities for >>>>> setting the operating mode (set DMA.CCC and wait for CSR.OPS) and call it >>>>> where needed. This should comply with all the HW manuals requirements as >>>>> different manual variants specify that different modes need to be checked >>>>> in CSR.OPS when setting DMA.CCC. >>>>> >>>>> Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") >>>>> Signed-off-by: Claudiu Beznea >>>>> --- >>>>> drivers/net/ethernet/renesas/ravb_main.c | 52 ++++++++++++++---------- >>>>> 1 file changed, 31 insertions(+), 21 deletions(-) >>>>> >>>>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c >>>>> index 664eda4b5a11..ae99d035a3b6 100644 >>>>> --- a/drivers/net/ethernet/renesas/ravb_main.c >>>>> +++ b/drivers/net/ethernet/renesas/ravb_main.c >>>>> @@ -66,14 +66,15 @@ int ravb_wait(struct net_device *ndev, enum ravb_reg reg, u32 mask, u32 value) >>>>> return -ETIMEDOUT; >>>>> } >>>>> >>>>> -static int ravb_config(struct net_device *ndev) >>>>> +static int ravb_set_opmode(struct net_device *ndev, u32 opmode) >>>> >>>> Since you pass the complete CCC register value below, you should >>>> rather call the function ravb_set_ccc() and call the parameter opmode >>>> ccc. >>> >>> This will be confusing. E.g., if renaming it ravb_set_ccc() one would >>> expect to set any fields of CCC though this function but this is not true >>> as ravb_modify() in this function masks only CCC_OPC. The call of: >>> >>> error = ravb_set_opmode(ndev, CCC_OPC_CONFIG | CCC_GAC | CCC_CSEL_HPB); >>> >>> bellow is just to comply with datasheet requirements, previous code and at >>> the same time re-use this function. >> >> How about the following then (ugly... but does the job): >> >> /* Set operating mode */ >> if (opmode & ~CCC_OPC) >> ravb_write(ndev, opmode, CCC); >> else >> ravb_modify(ndev, CCC, CCC_OPC, opmode); >> >> Either that or just don't use ravb_set_opmode() when writing the whole >> 32-bit value below... > > This looks uglier to me... > > We have this discussion because of ccc_gac. For ccc_gac platforms we need > to set OPC, GAC, CSEL at the same time. This is how we can change the > operating mode to configuration mode in case we also need to configure GAC > (due to restrictions imposed by hardware). > > What I want to say is that setting GAC and CSEL along with CCC is part of > changing the operating mode to configuration mode for platforms supporting > GAC because of hardware limitations. After thinking about it once more, your description seems correct. But then we need something like this: static int ravb_set_opmode(struct net_device *ndev, u32 opmode) { u32 ccc_mask = CCC_OPC; u32 csr_ops = 1U << (opmode & CCC_OPC); int error; if (opmode & CCC_GAC) ccc_mask |= CCC_CSEL; /* Set operating mode */ ravb_modify(ndev, CCC, ccc_mask, opmode); /* Check if the operating mode is changed to the requested one */ error = ravb_wait(ndev, CSR, CSR_OPS, csr_ops); if (error) netdev_err(ndev, "failed to switch device to requested mode\n"); return error; } [...] MBR, Sergey