Tony, > -----Original Message----- > From: Ghorai, Sukumar > Sent: Saturday, September 18, 2010 11:55 PM > To: 'Tony Lindgren' > Cc: 'linux-omap@xxxxxxxxxxxxxxx'; 'linux-mtd@xxxxxxxxxxxxxxxxxxx'; 'linux- > arm-kernel@xxxxxxxxxxxxxxxxxxx' > Subject: RE: [PATCH RESEND v4 1/4] omap3: nand: prefetch in irq mode > support > > Tony, > > > -----Original Message----- > > From: Tony Lindgren [mailto:tony@xxxxxxxxxxx] > > Sent: Friday, September 17, 2010 11:25 PM > > To: Ghorai, Sukumar > > Cc: linux-omap@xxxxxxxxxxxxxxx; linux-mtd@xxxxxxxxxxxxxxxxxxx; linux- > arm- > > kernel@xxxxxxxxxxxxxxxxxxx; Vimal Singh > > Subject: Re: [PATCH RESEND v4 1/4] omap3: nand: prefetch in irq mode > > support > > > > * Sukumar Ghorai <s-ghorai@xxxxxx> [100916 00:53]: > > > This patch enable prefetch-irq mode for NAND. > > > > > > --- a/drivers/mtd/nand/omap2.c > > > +++ b/drivers/mtd/nand/omap2.c > > > @@ -467,6 +485,152 @@ static void omap_write_buf_dma_pref(struct > > mtd_info *mtd, > > > omap_nand_dma_transfer(mtd, (u_char *) buf, len, 0x1); > > > } > > > > > > +/* > > > + * omap_nand_irq - GMPC irq handler > > > + * @this_irq: gpmc irq number > > > + * @dev: omap_nand_info structure pointer is passed here > > > + */ > > > +static irqreturn_t omap_nand_irq(int this_irq, void *dev) > > > +{ > > > + struct omap_nand_info *info = (struct omap_nand_info *) dev; > > > + u32 bytes; > > > + u32 irq_stat; > > > + > > > + irq_stat = gpmc_read_status(GPMC_GET_IRQ_STATUS); > > > + bytes = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT); > > > + bytes = bytes & 0xFFFC; /* io in multiple of 4 bytes */ > > > + if (info->iomode == OMAP_NAND_IO_WRITE) { /* checks for write io */ > > > + if (irq_stat & 0x2) > > > + goto done; > > > + > > > + if (info->buf_len & (info->buf_len < bytes)) > > > + bytes = info->buf_len; > > > + else if (!info->buf_len) > > > + bytes = 0; > > > + iowrite32_rep(info->nand.IO_ADDR_W, > > > + (u32 *)info->buf, bytes >> 2); > > > + info->buf = info->buf + bytes; > > > + info->buf_len -= bytes; > > > + > > > + } else { > > > + ioread32_rep(info->nand.IO_ADDR_R, > > > + (u32 *)info->buf, bytes >> 2); > > > + info->buf = info->buf + bytes; > > > + > > > + if (irq_stat & 0x2) > > > + goto done; > > > + } > > > + gpmc_cs_configure(info->gpmc_cs, GPMC_SET_IRQ_STATUS, irq_stat); > > > + irq_stat = gpmc_read_status(GPMC_GET_IRQ_STATUS); > > > + > > > + return IRQ_HANDLED; > > > + > > > +done: > > > + complete(&info->comp); > > > + /* disable irq */ > > > + gpmc_cs_configure(info->gpmc_cs, GPMC_ENABLE_IRQ, 0); > > > + > > > + /* clear status */ > > > + gpmc_cs_configure(info->gpmc_cs, GPMC_SET_IRQ_STATUS, irq_stat); > > > + irq_stat = gpmc_read_status(GPMC_GET_IRQ_STATUS); > > > + > > > + return IRQ_HANDLED; > > > +} > > > > This handler should be in gpmc.c as it may be needed for other GPMC > > connected devices on the same system. You can use chained irq handlers > > to allow all the drivers to use the interrupt then. > > [Ghorai] > You mean as this function used the gpmc-irq number in nand file, so > handler should move to gpmc.c file? > 1. For that we need to add one io-struct (to keep io buffer status) > in gpmc.c; > > 2. Also need help how to sync between gpmc.c/omap_nand_irq() and > omap2.c/omap_write_buf_irq_pref(), men how read/write function know that > work done in interrupt-context? Or you prefer to move the complete IO > function (omap_read/write_buf_irq_pref) to gpmc.c? > > 3. gpmc does not now about the read and write address that's > applicable for NAND. So how to pass the IO address from omap2.c to gpmc.c, > interrupt handler? > > > So, please let me know your suggestion again such that I can post this > time itself. Otherwise again it will miss from coming release, this was > posted/reviewed for last release too. And suggest to void repeating of > missing release window again. [Ghorai] Please reply with your 2nd suggestion. > > > > > Regards, > > > > Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
