Received-SPF: softfail (google.com: domain of transitioning linux-kernel-owner@vger.kernel.org does not designate 23.128.96.19 as permitted sender) client-ip=23.128.96.19;
Message-ID: <4d7f39188b76d509909b0c6274ad2bd89723b8d4.camel@nxp.com>
Subject: Re: [PATCH] clk: imx: clk-fracn-gppll: Return rate in rate table
 properly in ->recalc_rate()
From:   Liu Ying <victor.liu@nxp.com>
To:     Peng Fan <peng.fan@nxp.com>,
        "linux-clk@vger.kernel.org" <linux-clk@vger.kernel.org>,
        "linux-arm-kernel@lists.infradead.org" 
        <linux-arm-kernel@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Cc:     Abel Vesa <abel.vesa@nxp.com>,
        Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        dl-linux-imx <linux-imx@nxp.com>
Date:   Tue, 31 May 2022 09:45:52 +0800
In-Reply-To: <DU0PR04MB94172EA72CC1D6DEFE03CEAD88DD9@DU0PR04MB9417.eurprd04.prod.outlook.com>
References: <20220529071156.2511568-1-victor.liu@nxp.com>
         <DU0PR04MB94172CDB8AE355ACB0AFF0CF88DD9@DU0PR04MB9417.eurprd04.prod.outlook.com>
         <DU0PR04MB94172EA72CC1D6DEFE03CEAD88DD9@DU0PR04MB9417.eurprd04.prod.outlook.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?bUlURmJvNjBwMzB4bHhSRitCQm5LSEl1bnpzMk1jOUF6MjBIa1M3K3dBTkFr?=
 =?utf-8?B?ZldrTVNQSVNtUDE0S0ZIem16SVpHbVRubVowQ2FUb2ViN1lxQjV6bG1ZYzZo?=
 =?utf-8?B?dWpNQWQ5S1h5T05FNExnQWsxTy9Gbzcxd2dBV0xKSUk1cFZtdkFOaWt2aGdP?=
 =?utf-8?B?MzdaTVEvd3Z1NVRqZFhFckdKRFpEdWtlUFM0b0pWUnFVdUcwTVVnYk4xaHZZ?=
 =?utf-8?B?WDdBcjA0MU9zQUVwTUNNYXZvbVgyazZRQmppbGpYcVYwbWszVmdFcTMzWkdK?=
 =?utf-8?B?K2hpWjJRb2Nndmh2b0RlVVk2RWlBb0ZPOS8wOHlxNjRVbXB3Yko4by9nY0Nr?=
 =?utf-8?B?ODkyYldLQW1BYVV6cERtOHN0ZmxoQ3lTc3FERFFValQ5T2QwSXhyMk5pdHFF?=
 =?utf-8?B?ODF2NWpHemdSTERtUXUzTDQ5eWxsTndGWjNUZFUwNGJMckJyRk0zZStQYUg2?=
 =?utf-8?B?THRZZXdLRWwzTTUrOWlDZ0g5SWJXUDh6cmtzWk5CaXRTR3NBd0hJem0yOTR2?=
 =?utf-8?B?a0djZEZseHdOZDVWaHR3bVJqN1RnQzVPTDQ1d1hVaTRicW14MktlUllxMEFa?=
 =?utf-8?B?YmZaSUZxQ2ZiUnlUVDhnL2lGcFNLOFJzdnVpSkhpYmg1WkR6K0tWdWFpYnNz?=
 =?utf-8?B?bjc4M1NqNUNSdHVvVmx1akYxNWNEZExMR2UrcmhzYkJ4QVBNNUNrVzJaUHIr?=
 =?utf-8?B?eGpId3pmT3ZEWno0cXNlZnBxRStlWjlFUWUzL0xOUmMrZTQxRWxFOWZUWVZB?=
 =?utf-8?B?bVYyQThseHI1MFpjTllGemNRa1NuUjk0Tm1NRk5RWU1KNzRZdXNzZ3hOcXNx?=
 =?utf-8?B?QStOaHU2NzZYRVo3d0JaWTdZUzFwVGd1bXhFMk9FUENTNTZaL0xid2hubWNS?=
 =?utf-8?B?ZTlFOVI0NXhvak54QWRKa0V2aTRCUjlaK3dsWWVQMzZWb1llT2EwSGZ3SldZ?=
 =?utf-8?B?NUlPbjFYeWhmazgvQXJKWnlyRXJMWHUvY25xTzRZdXFpNFNJVDFLc29JSmhW?=
 =?utf-8?B?VzAzUnVQY1ZpaUZnS2NibXo3TDhiL2xRS2RmOTlvUGp6aVdpd2h0TUg3a1Np?=
 =?utf-8?B?Rnd3VzAzQmxIdmEwVE9Jc3ZHZTVBOGNQc3FGVlo5NEJ2Rlk1ZXk5N3ZONVdP?=
 =?utf-8?B?R2RiZkNmcU04SEp0U0xXektwYWthQTZMbUdEQndFd042cFRqM0pTMlp5eHJR?=
 =?utf-8?B?clZrbGhPbi9jYVNtbWZTV005Mnorcit6SjZWb05jbWNmR1pqeUkzeFhQQkZP?=
 =?utf-8?B?dXBSTCtWWXlkVTZhU0xkd1lyMENuZFpSS1NEYUR5V3lSRklGUC96ZldxTVds?=
 =?utf-8?B?S1U4RFYzSHdBY3h4ZS9RTFJTWVFTdCtZM0UvdzU2ZTg4dWtqaVQ3V1dUTHZw?=
 =?utf-8?B?NFdCWkFQTDdZK1oyWk4ybWQ4azJjRmpUSkl2Y0wxUytnZElKRUJGWWhBMmZh?=
 =?utf-8?B?VGxLbGlaQmM1ZXNLWGFYLy8yNHhVSG9RT0NqNlczRzQ4enQ1QVJlOURXcW9F?=
 =?utf-8?B?TWN0UGVoRVN2c1VHeDNxQmhNUk51L1lPYmd6djY4bkUycW8zdFE0YjllekJS?=
 =?utf-8?B?b1FXRXdpQW9Mc29wOXVqSERwQlFSOXhBUGlaR1FOaEpOSDhRSWtobTExYVJ2?=
 =?utf-8?B?eVUyOTN6N2VxV0pONzM5OUlOeVJaOEVtTS8vaEJwT0RTeFRUczdMR2VnVGdX?=
 =?utf-8?B?aG9lTHZ6ZWFmNkswc1RId0lJUFNVb0xkWGVVZW9XOWZya2RWNVp3K3pVYjdo?=
 =?utf-8?B?UWJyN1JkMlVaaWhBK20zVVEzWHYwTlh0K211QVFrcFdSS2VnNGFKRUMrYVph?=
 =?utf-8?B?WTdyNkpsVlVQdm05azdwb21HUUEyT3M2aGZqZHNvSDU0aldrVis2UVFqaUNF?=
 =?utf-8?B?bUhFei9FWlkrMjErWFpPZW5kcEhNNFdDS0VjanhoSXBzZmZ5T2l6eE1uU3ZF?=
 =?utf-8?B?TGNHbEdBZU9yOG5GQ2lXZnhYT3JWcURSSGQzM0FYVWlXeWpYU2RWV1FzcFRn?=
 =?utf-8?B?WFJ2ZHJNZ2RCbWFyV0JMdEZQYmN6bFFFMENEZktNUDBER3N5RHFnYjQ5cHFI?=
 =?utf-8?B?dU12bnN6Mk9OOGZwYTh6UGg4UHhQeGFjN0RDb1I3SmpCMS9STmZrZ3RnNk1V?=
 =?utf-8?B?SHM1aHk0c084TmpJVHhET2ozdnBRSFB1eVZPYUgvQ0xrV1RUNWthNVZBWXda?=
 =?utf-8?B?UEhqdllRVWRiUlNqRDRpY2swWEExZHZxbVNTOC90Uk1Zb2w2dGxCVXVFRWJQ?=
 =?utf-8?B?UWhKZy93dGFyQ3NSNlIwRmV2bHY0Wnp5MGlIdFBzZzJ2VVF2aFFocVpOR2Mx?=
 =?utf-8?B?bWFpbUdqMWdvZW44RmFpNmFBdC80L0NjeElveTBMV1VOYW8yRW9CQT09?=
X-OriginatorOrg: nxp.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 1fe57e83-a1fa-4f03-aecb-08da42a763a6
X-MS-Exchange-CrossTenant-AuthSource: AM7PR04MB7046.eurprd04.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 31 May 2022 01:46:32.8011
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: aVnFcbQMjQQCvIDpDKACUTx7DPY4oM2thnFNcGCov3JHATiqqXfKeqDj2ez0YePvqoyvUHAXKhXXd1Cf8SRIrQ==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB6PR04MB2949
X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED,
	DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,
	MAILING_LIST_MULTI,RDNS_NONE,SPF_HELO_NONE,T_SCC_BODY_TEXT_LINE
	autolearn=no autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
	lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Hi Peng,

On Mon, 2022-05-30 at 17:08 +0800, Peng Fan wrote:
> > Subject: RE: [PATCH] clk: imx: clk-fracn-gppll: Return rate in rate
> > table properly
> > in ->recalc_rate()
> > 
> > > Subject: [PATCH] clk: imx: clk-fracn-gppll: Return rate in rate
> > > table
> > > properly in
> > > ->recalc_rate()
> > > 
> > > The PLL parameters in rate table should be directly compared with
> > > those read from PLL registers instead of the cooked ones.
> > > 
> > > Fixes: 1b26cb8a77a4 ("clk: imx: support fracn gppll")
> > > Cc: Abel Vesa <abel.vesa@nxp.com>
> > > Cc: Michael Turquette <mturquette@baylibre.com>
> > > Cc: Stephen Boyd <sboyd@kernel.org>
> > > Cc: Shawn Guo <shawnguo@kernel.org>
> > > Cc: Sascha Hauer <s.hauer@pengutronix.de>
> > > Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
> > > Cc: Fabio Estevam <festevam@gmail.com>
> > > Cc: NXP Linux Team <linux-imx@nxp.com>
> > > Cc: Peng Fan <peng.fan@nxp.com>
> > > Signed-off-by: Liu Ying <victor.liu@nxp.com>
> > 
> > Reviewed-by: Peng Fan <peng.fan@nxp.com>
> > 
> > > ---
> > >  drivers/clk/imx/clk-fracn-gppll.c | 24 +++++++++++++-----------
> > >  1 file changed, 13 insertions(+), 11 deletions(-)
> > > 
> > > diff --git a/drivers/clk/imx/clk-fracn-gppll.c
> > > b/drivers/clk/imx/clk-fracn-gppll.c
> > > index 71c102d950ab..762b07dd5a6d 100644
> > > --- a/drivers/clk/imx/clk-fracn-gppll.c
> > > +++ b/drivers/clk/imx/clk-fracn-gppll.c
> > > @@ -131,18 +131,7 @@ static unsigned long
> > > clk_fracn_gppll_recalc_rate(struct clk_hw *hw, unsigned lon
> > >  	mfi = FIELD_GET(PLL_MFI_MASK, pll_div);
> > > 
> > >  	rdiv = FIELD_GET(PLL_RDIV_MASK, pll_div);
> > > -	rdiv = rdiv + 1;
> > >  	odiv = FIELD_GET(PLL_ODIV_MASK, pll_div);
> > > -	switch (odiv) {
> > > -	case 0:
> > > -		odiv = 2;
> > > -		break;
> > > -	case 1:
> > > -		odiv = 3;
> > > -		break;
> > > -	default:
> > > -		break;
> > > -	}
> > > 
> > >  	/*
> > >  	 * Sometimes, the recalculated rate has deviation due to @@
> > > -160,6
> > > +149,19 @@ static unsigned long
> > > clk_fracn_gppll_recalc_rate(struct
> > > +clk_hw
> > > *hw, unsigned lon
> > >  	if (rate)
> > >  		return (unsigned long)rate;
> > > 
> > > +	rdiv = rdiv + 1;
> 
> After check more:
> According to doc, needs add a check here:
> if (!rdiv)
>  rdiv = rdiv + 1;

This new check is not something this patch tries to deal with.
Maybe, you may send a separate patch to add the check.

Regards,
Liu Ying

> 
> Regards,
> Peng.
> > > +
> > > +	switch (odiv) {
> > > +	case 0:
> > > +		odiv = 2;
> > > +		break;
> > > +	case 1:
> > > +		odiv = 3;
> > > +		break;
> > > +	default:
> > > +		break;
> > > +	}
> > > +
> > >  	/* Fvco = Fref * (MFI + MFN / MFD) */
> > >  	fvco = fvco * mfi * mfd + fvco * mfn;
> > >  	do_div(fvco, mfd * rdiv * odiv);
> > > --
> > > 2.25.1
> 
>