Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Mon, 8 Mar 2021 19:04:10 +0530
From:   Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
To:     Boris Brezillon <boris.brezillon@collabora.com>
Cc:     miquel.raynal@bootlin.com, richard@nod.at, vigneshr@ti.com,
        robh+dt@kernel.org, linux-arm-msm@vger.kernel.org,
        devicetree@vger.kernel.org, linux-mtd@lists.infradead.org,
        linux-kernel@vger.kernel.org, Daniele.Palmas@telit.com,
        bjorn.andersson@linaro.org
Subject: Re: [PATCH v4 3/3] mtd: rawnand: qcom: Add support for secure
 regions in NAND memory
Message-ID: <20210308133410.GD5457@thinkpad>
References: <20210308054447.28418-1-manivannan.sadhasivam@linaro.org>
 <20210308054447.28418-4-manivannan.sadhasivam@linaro.org>
 <20210308100247.4aba657c@collabora.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20210308100247.4aba657c@collabora.com>
Precedence: bulk

On Mon, Mar 08, 2021 at 10:02:47AM +0100, Boris Brezillon wrote:
> On Mon,  8 Mar 2021 11:14:47 +0530
> Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> wrote:
> 

[...]

> >  /* helper to configure address register values */
> > -static void set_address(struct qcom_nand_host *host, u16 column, int page)
> > +static int set_address(struct qcom_nand_host *host, u16 column, int page)
> >  {
> >  	struct nand_chip *chip = &host->chip;
> >  	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
> > +	u32 offs = page << chip->page_shift;
> > +	int i, j;
> > +
> > +	/* Skip touching the secure regions if present */
> > +	for (i = 0, j = 0; i < host->nr_sec_regions; i++, j += 2) {
> > +		if (offs >= host->sec_regions[j] &&
> > +		    (offs <= host->sec_regions[j] + host->sec_regions[j + 1]))
> > +			return -EIO;
> > +	}
> 
> Hm, not sure that's a good idea to make this check part of
> set_address(). Looks like set_address() can be used for ONFI page
> access too, and you definitely don't want to block those
> requests. I'd recommend having a separate helper that you can call from
> qcom_nandc_{read,write}_{oob,page,page_raw}().
> 

Right but I went for the code simplicity :/ Anyway, since you're favoring
towards moving this check into code, I'll incorporate your suggestion
accordingly.

Thanks,
Mani