[U-Boot] [PATCH 2/2 v3] arm: suen3, suen3_v1, mgcoge2_arm_p1a support

[Heiko Schocher <hs@denx.de>]

Hello Scott,

Scott Wood wrote:
> On Wed, Feb 03, 2010 at 04:52:05PM +0100, Heiko Schocher wrote:
>>>> +	if ((strcmp(argv[1], "off") == 0)) {
>>>> +		printf("SPI FLASH disabled, NAND enabled\n");
>>>> +		/* Multi-Purpose Pins Functionality configuration */
>>>> +		kwmpp_config[0] = MPP0_NF_IO2;
>>>> +		kwmpp_config[1] = MPP1_NF_IO3;
>>>> +		kwmpp_config[2] = MPP2_NF_IO4;
>>>> +		kwmpp_config[3] = MPP3_NF_IO5;
>>>> +
>>>> +		kirkwood_mpp_conf(kwmpp_config);
>>>> +		tmp = readl(KW_GPIO0_BASE);
>>>> +		writel(tmp | FLASH_GPIO_PIN , KW_GPIO0_BASE);
>>>> +
>>>> +		nand_init();
>>>> +	} else if ((strcmp(argv[1], "on") == 0)) {
>>>> +		printf("SPI FLASH enabled, NAND disabled\n");
>>>> +		/* Multi-Purpose Pins Functionality configuration */
>>>> +		kwmpp_config[0] = MPP0_SPI_SCn;
>>>> +		kwmpp_config[1] = MPP1_SPI_MOSI;
>>>> +		kwmpp_config[2] = MPP2_SPI_SCK;
>>>> +		kwmpp_config[3] = MPP3_SPI_MISO;
>>>> +
>>>> +		kirkwood_mpp_conf(kwmpp_config);
>>>> +		tmp = readl(KW_GPIO0_BASE);
>>>> +		writel(tmp & (~FLASH_GPIO_PIN) , KW_GPIO0_BASE);
>>>> +
>>>> +		nand_init();
>>> What do you need nand_init for disabled nand operation?
>> With it, the nand subsystem knows, that there is no longer
>> the nand availiable.
> 
> That's not how nand_init() is meant to be used.  It is meant to be called
> once on system init.  There is probably at least a memory leak here, e.g.
> chip->buffers.

Oh, Ok. How could/should this then be solved?

(Some weak function, maybe: int nand_available(void)?, that board specific
 code can overwrite, and this function is checked before a nand command
 is executed?)

In the First step, I don;t call nand_init() again, there is also a
 warning message, that NAND is disabled, so the user should know, that
 he don;t have longer access to it, is this Okay for you?

> Even as a hack, it looks like these boards use the kirkwood nand controller,
> and its board_nand_init() will unconditionally return 0, telling

Yep, but ...

> nand_init_chip that it does indeed have NAND available.  Or is there a patch
> somewhere changing that?

... nand_get_flash_type() returns -ENODEV, if no manufacturer or/and
id could be read from nand (And if using this u-boot command, the nand
is not longer visible, because the nand is disabled, and the pins are
used to access a SPI Flash) -> nand_scan_ident returns this error, and
so nand_scan ...

Actually, I get this message, when running this code:

No NAND device found!!!


Thanks for your comment.

bye
Heiko
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