Re: [PATCH 1/9] mtd: sh_flctl: Add support for error IRQ

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Bastian,

Thanks for the patch.

On Friday 20 April 2012 11:13:42 Bastian Hecht wrote:
> When the data transfer between the controller and the NAND chip fails,
> we now get notified.
> 
> Signed-off-by: Bastian Hecht <hechtb@gmail.com>
> ---
>  drivers/mtd/nand/sh_flctl.c  |   31 +++++++++++++++++++++++++++++--
>  include/linux/mtd/sh_flctl.h |    7 +++++++
>  2 files changed, 36 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/mtd/nand/sh_flctl.c b/drivers/mtd/nand/sh_flctl.c
> index 2ee9a1b..3c27921 100644
> --- a/drivers/mtd/nand/sh_flctl.c
> +++ b/drivers/mtd/nand/sh_flctl.c
> @@ -24,6 +24,7 @@
>  #include <linux/module.h>
>  #include <linux/kernel.h>
>  #include <linux/delay.h>
> +#include <linux/interrupt.h>
>  #include <linux/io.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_runtime.h>
> @@ -69,7 +70,7 @@ static struct nand_bbt_descr flctl_4secc_largepage = {
>  static void empty_fifo(struct sh_flctl *flctl)
>  {
>  	writel(0x000c0000, FLINTDMACR(flctl));	/* FIFO Clear */

Shouldn't this write flctl->flintdmacr_base | 0x000c0000 ? If you change this 
line, you could also define and use the AC1CLR and AC0CLR bits.

> -	writel(0x00000000, FLINTDMACR(flctl));	/* Clear Error flags */
> +	writel(flctl->flintdmacr_base, FLINTDMACR(flctl));
>  }
> 
>  static void start_translation(struct sh_flctl *flctl)
> @@ -838,6 +839,14 @@ static int flctl_chip_init_tail(struct mtd_info *mtd)
>  	return 0;
>  }
> 
> +static irqreturn_t flctl_handle_flste(int irq, void *dev_id)
> +{
> +	struct sh_flctl *flctl = dev_id;
> +	dev_err(&flctl->pdev->dev, "flste irq: %x\n", readl(FLINTDMACR(flctl)));
> +

You should clear the interrupt flags here, otherwise endless interrupts will 
occur. I suppose this will be fixed in a later patch, but it's a good practice 
to avoid breaking git bisect.

> +	return IRQ_HANDLED;
> +}
> +
>  static int __devinit flctl_probe(struct platform_device *pdev)
>  {
>  	struct resource *res;
> @@ -846,6 +855,7 @@ static int __devinit flctl_probe(struct platform_device
> *pdev) struct nand_chip *nand;
>  	struct sh_flctl_platform_data *pdata;
>  	int ret = -ENXIO;
> +	int irq;
> 
>  	pdata = pdev->dev.platform_data;
>  	if (pdata == NULL) {
> @@ -871,14 +881,27 @@ static int __devinit flctl_probe(struct
> platform_device *pdev) goto err_iomap;
>  	}
> 
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0) {
> +		dev_err(&pdev->dev, "failed to get flste irq data\n");
> +		goto err_flste;
> +	}
> +
> +	ret = request_irq(irq, flctl_handle_flste, IRQF_SHARED, "flste", flctl);
> +	if (ret) {
> +		dev_err(&pdev->dev, "request interrupt failed.\n");
> +		goto err_flste;
> +	}
> +
>  	platform_set_drvdata(pdev, flctl);
>  	flctl_mtd = &flctl->mtd;
>  	nand = &flctl->chip;
>  	flctl_mtd->priv = nand;
>  	flctl->pdev = pdev;
> -	flctl->flcmncr_base = pdata->flcmncr_val;
>  	flctl->hwecc = pdata->has_hwecc;
>  	flctl->holden = pdata->use_holden;
> +	flctl->flcmncr_base = pdata->flcmncr_val;
> +	flctl->flintdmacr_base = flctl->hwecc ? (STERINTE | ECERB) : STERINTE;
> 
>  	nand->options = NAND_NO_AUTOINCR;
> 
> @@ -919,6 +942,9 @@ static int __devinit flctl_probe(struct platform_device
> *pdev)
> 
>  err_chip:
>  	pm_runtime_disable(&pdev->dev);
> +	free_irq(platform_get_irq(pdev, 0), flctl);
> +err_flste:
> +	iounmap(flctl->reg);

The missing iounmap() is a separate issue, you should split it to its own 
patch. It's also seems to be missing in flctl_remove() btw.

>  err_iomap:
>  	kfree(flctl);
>  	return ret;
> @@ -930,6 +956,7 @@ static int __devexit flctl_remove(struct platform_device
> *pdev)
> 
>  	nand_release(&flctl->mtd);
>  	pm_runtime_disable(&pdev->dev);
> +	free_irq(platform_get_irq(pdev, 0), flctl);
>  	kfree(flctl);
> 
>  	return 0;
> diff --git a/include/linux/mtd/sh_flctl.h b/include/linux/mtd/sh_flctl.h
> index a38e1fa..6832a90 100644
> --- a/include/linux/mtd/sh_flctl.h
> +++ b/include/linux/mtd/sh_flctl.h
> @@ -107,6 +107,12 @@
>  #define DOCMD2_E	(0x1 << 17)	/* 2nd cmd stage execute */
>  #define DOCMD1_E	(0x1 << 16)	/* 1st cmd stage execute */
> 
> +/* FLINTDMACR control bits */
> +#define ESTERINTE	(0x1 << 24)	/* ECC error interrupt enable */
> +#define ECERB		(0x1 << 9)	/* ECC error */
> +#define STERB		(0x1 << 8)	/* Status error */
> +#define STERINTE	(0x1 << 4)	/* Status error enable */
> +
>  /* FLTRCR control bits */
>  #define TRSTRT		(0x1 << 0)	/* translation start */
>  #define TREND		(0x1 << 1)	/* translation end */
> @@ -145,6 +151,7 @@ struct sh_flctl {
>  	uint32_t erase_ADRCNT;		/* bits of FLCMDCR in ERASE1 cmd */
>  	uint32_t rw_ADRCNT;	/* bits of FLCMDCR in READ WRITE cmd */
>  	uint32_t flcmncr_base;	/* base value of FLCMNCR */
> +	uint32_t flintdmacr_base;	/* irq enable bits */
> 
>  	int	hwecc_cant_correct[4];
-- 
Regards,

Laurent Pinchart