[U-Boot] [PATCH 5/7] S3C24XX: Add NAND Flash driver
Marek Vasut
marex at denx.de
Thu Sep 13 01:45:07 CEST 2012
Dear José Miguel Gonçalves,
> Hi Marek,
>
> On 09/12/2012 10:11 PM, Marek Vasut wrote:
> > Dear José Miguel Gonçalves,
> >
> >> +
> >> +/*
> >> + * Hardware specific access to control-lines function
> >> + */
> >> +static void s3c_nand_hwcontrol(struct mtd_info *mtd, int cmd, unsigned
> >> int ctrl) +{
> >> + s3c24xx_nand *const nand = s3c24xx_get_base_nand();
> >> + struct nand_chip *this = mtd->priv;
> >> +
> >> + if (ctrl & NAND_CTRL_CHANGE) {
> >> + if (ctrl & NAND_CLE)
> >> + this->IO_ADDR_W = (void __iomem *)&nand->nfcmmd;
> >> + else if (ctrl & NAND_ALE)
> >> + this->IO_ADDR_W = (void __iomem *)&nand->nfaddr;
> >> + else
> >> + this->IO_ADDR_W = (void __iomem *)&nand->nfdata;
> >
> > Do you need this cast ?
>
> Without it gcc gives me a warning:
>
> s3c24xx_nand.c:90:20: warning: assignment discards `volatile' qualifier
> from pointer target type [enabled by default]
Not that you need to do the assignment into the structure .... use local
variable, no ?
> > +/*
> > + * Board-specific NAND initialization.
> > + */
> > +int board_nand_init(struct nand_chip *nand)
> > +{
> > + static int chip_n = 0;
> > + s3c24xx_nand *const nand_reg = s3c24xx_get_base_nand();
> > + u_long nfconf, nfcont;
> > +
> > + if (chip_n == 0) {
> > + /* Extend NAND timings to the maximum */
> > + nfconf = readl(&nand_reg->nfconf);
> > + nfconf |= 0x7770;
> > Magic
> >
> >> + writel(nfconf, &nand_reg->nfconf);
> >> +
> >> + /* Disable chip selects and soft lock, enable controller */
> >> + nfcont = readl(&nand_reg->nfcont);
> >> + nfcont &= ~NFCONT_WP;
> >> + nfcont |= NFCONT_NCE1 | NFCONT_NCE0 | NFCONT_ENABLE;
> >> + writel(nfcont, &nand_reg->nfcont);
> >
> > use clrsetbits_le32()
>
> I will do that and also define some macros for the magic values.
>
> Regards,
> José Gonçalves
Best regards,
Marek Vasut
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