NAND connected with address lines based example

NAND connected with address lines based example

[Marcus Mikolaiczyk]

Dear list users,

I got a system where a Samsung NAND ist connect  via Adresslines (A0 ->
CLE, A1 -> ALE) using a chipselect from the processor. I looked through
the guide "MTD NAND Driver Programming Interface" and the sources to
adapt an existing driver. Now I stuck with a problem concerning the
board_hwcontrol function.
It's alwas there that CLE/ALE have a set and a clear command. But in my
setup the CLE/ALE setting is made through the access of the
addresslines. See the table:

        A1(ALE)   A0(CLE)  Beispieladresse    Funktion
-------------------------------------------------------------------------------
1         0         0       0xA8000000        read/write access on mem
2         0         1       0xA8000001        Command
3         1         0       0xA8000002        Addresssetting
4         1         1       0xA8000003        not valid

The base is A8000000 for example.
Now writing a Byte to 0xA8000001 (a NAND command) automatically sets ALE
=0 and CLE=1
Writing the addressparts is done through writing the 1st databyte Col1
to address 0xA8000002 and so on.
Concerning now the function board_hwcontrol there is the
...
switch(cmd) {
		case NAND_CTL_SETCLE: /* Write to addr 0xA8000001 */;break;
		case NAND_CTL_CLRCLE: /* do nothing */;break;
		case NAND_CTL_SETALE: /* Write to addr 0xA8000002 */;break;
		case NAND_CTL_CLRALE: /* do nothing */;break;
}
...
Am I right when these commands have to be empty in this case?
Where do I tell the system to use the address 0xA8000001 for commands
and 0xA8000002 for addresses?

Kind Regards

Marcus

Re: NAND connected with address lines based example

[William J Beksi]

Hi Marcus,

Marcus Mikolaiczyk wrote:
> Dear list users,
> 
> I got a system where a Samsung NAND ist connect  via Adresslines (A0 ->
> CLE, A1 -> ALE) using a chipselect from the processor. I looked through
> the guide "MTD NAND Driver Programming Interface" and the sources to
> adapt an existing driver. Now I stuck with a problem concerning the
> board_hwcontrol function.
> It's alwas there that CLE/ALE have a set and a clear command. But in my
> setup the CLE/ALE setting is made through the access of the
> addresslines. See the table:
> 
>         A1(ALE)   A0(CLE)  Beispieladresse    Funktion
> -------------------------------------------------------------------------------
> 1         0         0       0xA8000000        read/write access on mem
> 2         0         1       0xA8000001        Command
> 3         1         0       0xA8000002        Addresssetting
> 4         1         1       0xA8000003        not valid
> 
> The base is A8000000 for example.
> Now writing a Byte to 0xA8000001 (a NAND command) automatically sets ALE
> =0 and CLE=1
> Writing the addressparts is done through writing the 1st databyte Col1
> to address 0xA8000002 and so on.
> Concerning now the function board_hwcontrol there is the
> ...
> switch(cmd) {
> 		case NAND_CTL_SETCLE: /* Write to addr 0xA8000001 */;break;
> 		case NAND_CTL_CLRCLE: /* do nothing */;break;
> 		case NAND_CTL_SETALE: /* Write to addr 0xA8000002 */;break;
> 		case NAND_CTL_CLRALE: /* do nothing */;break;
> }
> ...
> Am I right when these commands have to be empty in this case?
> Where do I tell the system to use the address 0xA8000001 for commands
> and 0xA8000002 for addresses?

You can write your hardware control function like this:

switch(cmd) {
	case NAND_CTL_SETCLE: this->IO_ADDR_W = io_base_addr+1; break;
	case NAND_CTL_CLRCLE: this->IO_ADDR_W = io_base_addr; break;
	case NAND_CTL_SETALE: this->IO_ADDR_W = io_base_addr+2; break;	
	case NAND_CTL_CLRALE: this->IO_ADDR_W = io_base_addr; break;
}

Where io_base_addr = A8000000, your base address.

Hope this helps.
-- 
William J Beksi                          <wjbeksi@users.sourceforge.net>
GPG Key Fingerprint = ED4B 32C3 69E6 C2B7 705C  263F CB2F 3253 E7E1 DB3B

Re: NAND connected with address lines based example

[Pathompong Puengrostham]

Marcus Mikolaiczyk wrote:
> Dear list users,
> 
> I got a system where a Samsung NAND ist connect  via Adresslines (A0 ->
> CLE, A1 -> ALE) using a chipselect from the processor. I looked through
> the guide "MTD NAND Driver Programming Interface" and the sources to
> adapt an existing driver. Now I stuck with a problem concerning the
> board_hwcontrol function.
> It's alwas there that CLE/ALE have a set and a clear command. But in my
> setup the CLE/ALE setting is made through the access of the
> addresslines. See the table:
> 
>         A1(ALE)   A0(CLE)  Beispieladresse    Funktion
> -------------------------------------------------------------------------------
> 1         0         0       0xA8000000        read/write access on mem
> 2         0         1       0xA8000001        Command
> 3         1         0       0xA8000002        Addresssetting
> 4         1         1       0xA8000003        not valid
> 
> The base is A8000000 for example.
> Now writing a Byte to 0xA8000001 (a NAND command) automatically sets ALE
> =0 and CLE=1
> Writing the addressparts is done through writing the 1st databyte Col1
> to address 0xA8000002 and so on.
> Concerning now the function board_hwcontrol there is the
> ...
> switch(cmd) {
> 		case NAND_CTL_SETCLE: /* Write to addr 0xA8000001 */;break;
> 		case NAND_CTL_CLRCLE: /* do nothing */;break;
> 		case NAND_CTL_SETALE: /* Write to addr 0xA8000002 */;break;
> 		case NAND_CTL_CLRALE: /* do nothing */;break;
> }
> ...
> Am I right when these commands have to be empty in this case?
> Where do I tell the system to use the address 0xA8000001 for commands
> and 0xA8000002 for addresses?
> 
> Kind Regards
> 
> Marcus

You could do something like this I suppose.

struct nand_chip *this = mtd->priv;
switch(cmd) {
	case NAND_CTL_SETCLE: this->IO_ADDR_R = this->IO_ADDR_W = 0xA8000001; 
break;
	case NAND_CTL_CLRCLE: this->IO_ADDR_R = this->IO_ADDR_W = 0xA8000000; 
break;
}

That what I'd do.

Regards,
Pathompong Puengrostham

Re: NAND connected with address lines based example

[Marcus Mikolaiczyk]

Thanks to all

I'll thought of Williams idea too but was not sure, and try to implement
it asap (next few hours) and give a feedback.
>
> You can write your hardware control function like this:
>
> switch(cmd) {
>     case NAND_CTL_SETCLE: this->IO_ADDR_W = io_base_addr+1; break;
>     case NAND_CTL_CLRCLE: this->IO_ADDR_W = io_base_addr; break;
>     case NAND_CTL_SETALE: this->IO_ADDR_W = io_base_addr+2; break;
>     case NAND_CTL_CLRALE: this->IO_ADDR_W = io_base_addr; break;
> }
>
> Where io_base_addr = A8000000, your base address.
>
> Hope this helps.

Thanks so far.

Marcus

Re: NAND connected with address lines based example

[Thomas Gleixner]

On Thu, 2005-03-31 at 11:07 +0200, Marcus Mikolaiczyk wrote:
> Where do I tell the system to use the address 0xA8000001 for commands
> and 0xA8000002 for addresses?

http://www.linux-mtd.infradead.org/tech/mtdnand/x76.html

tglx