From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8E699C433E0 for ; Fri, 12 Feb 2021 08:21:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5898A64E6C for ; Fri, 12 Feb 2021 08:21:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229653AbhBLIUq convert rfc822-to-8bit (ORCPT ); Fri, 12 Feb 2021 03:20:46 -0500 Received: from relay3-d.mail.gandi.net ([217.70.183.195]:35123 "EHLO relay3-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229469AbhBLIUh (ORCPT ); Fri, 12 Feb 2021 03:20:37 -0500 X-Originating-IP: 90.2.4.167 Received: from xps13 (aputeaux-654-1-105-167.w90-2.abo.wanadoo.fr [90.2.4.167]) (Authenticated sender: miquel.raynal@bootlin.com) by relay3-d.mail.gandi.net (Postfix) with ESMTPSA id 3D36A60010; Fri, 12 Feb 2021 08:19:46 +0000 (UTC) Date: Fri, 12 Feb 2021 09:19:45 +0100 From: Miquel Raynal To: mdalam@codeaurora.org Cc: Manivannan Sadhasivam , boris.brezillon@collabora.com, linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, vigneshr@ti.com, sricharan@codeaurora.org Subject: Re: [PATCH V4] mtd: rawnand: qcom: update last code word register Message-ID: <20210212091945.304c2530@xps13> In-Reply-To: References: <1611869959-5109-1-git-send-email-mdalam@codeaurora.org> <20210210090144.GE19226@work> <20210211150759.506f3463@xps13> Organization: Bootlin X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, mdalam@codeaurora.org wrote on Fri, 12 Feb 2021 01:00:47 +0530: > On 2021-02-11 19:37, Miquel Raynal wrote: > > Hello, > > > > Manivannan Sadhasivam wrote on Wed, > > 10 Feb 2021 14:31:44 +0530: > > > >> On Fri, Jan 29, 2021 at 03:09:19AM +0530, Md Sadre Alam wrote: > >> > From QPIC version 2.0 onwards new register got added to > >> > read last codeword. This change will add the READ_LOCATION_LAST_CW_n > >> > register. > >> > > >> > For first three code word READ_LOCATION_n register will be > >> > use.For last code word READ_LOCATION_LAST_CW_n register will be > >> > use. > > > > Sorry for the late notice, I think the patch is fine but if you don't > > mind I would like to propose a small change that should simplify your > > patch a lot, see below. > > > >> > > >> > Signed-off-by: Md Sadre Alam > >> >> Reviewed-by: Manivannan Sadhasivam > >> >> Thanks, > >> Mani > >> >> > --- > >> > [V4] > >> > * Modified condition for nandc_set_read_loc_last() in qcom_nandc_read_cw_raw(). > >> > * Added one additional argument "last_cw" to the function config_nand_cw_read() > >> > to handle last code word condition. > >> > * Changed total number of last code word register "NAND_READ_LOCATION_LAST_CW_0" to 4 > >> > while doing code word configuration. > >> > drivers/mtd/nand/raw/qcom_nandc.c | 110 +++++++++++++++++++++++++++++--------- > >> > 1 file changed, 84 insertions(+), 26 deletions(-) > >> > > >> > diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c > >> > index 667e4bf..9484be8 100644 > >> > --- a/drivers/mtd/nand/raw/qcom_nandc.c > >> > +++ b/drivers/mtd/nand/raw/qcom_nandc.c > >> > @@ -48,6 +48,10 @@ > >> > #define NAND_READ_LOCATION_1 0xf24 > >> > #define NAND_READ_LOCATION_2 0xf28 > >> > #define NAND_READ_LOCATION_3 0xf2c > >> > +#define NAND_READ_LOCATION_LAST_CW_0 0xf40 > >> > +#define NAND_READ_LOCATION_LAST_CW_1 0xf44 > >> > +#define NAND_READ_LOCATION_LAST_CW_2 0xf48 > >> > +#define NAND_READ_LOCATION_LAST_CW_3 0xf4c > >> > > >> > /* dummy register offsets, used by write_reg_dma */ > >> > #define NAND_DEV_CMD1_RESTORE 0xdead > >> > @@ -187,6 +191,12 @@ nandc_set_reg(nandc, NAND_READ_LOCATION_##reg, \ > >> > ((size) << READ_LOCATION_SIZE) | \ > >> > ((is_last) << READ_LOCATION_LAST)) > >> > > >> > +#define nandc_set_read_loc_last(nandc, reg, offset, size, is_last) \ > >> > +nandc_set_reg(nandc, NAND_READ_LOCATION_LAST_CW_##reg, \ > >> > + ((offset) << READ_LOCATION_OFFSET) | \ > >> > + ((size) << READ_LOCATION_SIZE) | \ > >> > + ((is_last) << READ_LOCATION_LAST)) > >> > + > > > > You could rename the macro nandc_set_read_loc() into > > nandc_set_read_loc_first() or anything else that make sense, then have > > a helper which does: > > > > nandc_set_read_loc() > > { > > if (condition for first) > > return nandc_set_read_loc_first(); > > else > > return nandc_set_read_loc_last(); > > } > > > > Yes this is more precise way & simplify the patch a lot. > But for this i have to change these two macro as a function. > > nandc_set_read_loc() & nandc_set_read_loc_last(). > > Since for last code word register we are using Token Pasting Operator##. > > So if i am implementing like the below. > > /* helper to configure location register values */ > static void nandc_set_read_loc(struct qcom_nand_controller *nandc, int reg, > int offset, int size, int is_last, bool last_cw) > { > if (last_cw) > return nandc_set_read_loc_last(nandc, reg, offset, size, is_last); > else > return nandc_set_read_loc_first(nandc, reg, offset, size, is_last); > } > > So here for macro expansion reg should be a value not a variable else it will be expended like > NAND_READ_LOCATION_LAST_CW_reg instead of NAND_READ_LOCATION_LAST_CW_0,1,2,3 etc. I know it involves a little bit more computation but I wonder if using funcs instead of macros here would not be nicer? Perhaps something like: loc = is_last ? NAND_READ_LOCATION /* 0xf20 */ : NAND_READ_LOCATION_LAST /* 0xf40 */; loc += reg * 2; > the call for nandc_set_read_loc() as nandc_set_read_loc(nandc, 0, read_loc, data_size1, 0, true); ---> for last code word. > nandc_set_read_loc(nandc, 0, read_loc, data_size1, 0, false); ---> for first three code wrod. I think it's best to forward 'cw' as a parameter and do the computation of is_last locally. > So is this ok for you to convert these two macro into function ? > > > And in the rest of your patch you won't have to touch anything else. > > > > Thanks, > > Miquèl Thanks, Miquèl