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charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: bp.renesas.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: TYCPR01MB5933.jpnprd01.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 19e4952e-84ed-414c-80d6-08da9f185030 X-MS-Exchange-CrossTenant-originalarrivaltime: 25 Sep 2022 17:06:39.9421 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 53d82571-da19-47e4-9cb4-625a166a4a2a X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: zZGVXUlJVeJv6IfrQntopdB4QHAjlPn9t21r6LqZQAMAcO7mGiPjCs1nJGLcV36HlvJ1J7oQKrXw1eFElbLKCxsysaUYpHtp0/9+r1GsGu4= X-MS-Exchange-Transport-CrossTenantHeadersStamped: TYYPR01MB7710 Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org Hi Wolfram, Thanks for the feedback. > Subject: Re: [PATCH v3] mmc: renesas_sdhi: Fix rounding errors >=20 > Hi, >=20 > > v2->v3: > > * Renamed the variable new_clock_margin->new_upper_limit in > renesas_sdhi_clk_ > > update() > > * Moved setting of new_upper_limit outside for loop. > > * Updated the comment section to mention the rounding errors and > merged with > > existing comment out side the for loop. > > * Updated commit description. >=20 > I really like the new variable names. >=20 > > + * To fix rounding errors, eg:- (533333333 Hz / 4 * 4 =3D 533333332 > Hz > > +< >=20 > (What is the '-' after 'eg:' for?) Regarding 'eg:-', I got this habit from school days. On exams, I usually write for eg:- to provide some examples. OK, Will remove '-' after 'eg:'. >=20 > > + * 533333333 Hz) add an upper limit of 1/1024 rate higher to the > clock > > + * rate. >=20 > I know Geert suggesgted this. I think, however, this description is > too short. It should be mentioned IMHO that this rounding error can > lead to the selection of a clock which is way off (the 400MHz one). I > liked this example from v2. Geert, what do you say? Yes, I can put back the real example from v2, if that is useful. 533MHz->400 MHz is a big jump due to this rounding error and it has impacted the performance. Waiting for Geert's feedback. Cheers, Biju