MTD partitions vs erase regions

MTD partitions vs erase regions

[Krzeminski, Marcin (Nokia - PL/Wroclaw)]

Hi Marek,

I am sending mtd partition and erase regions conflict that I had.
I admit I have no investigated it, since finally all is different.
This could make some problems with your idea of having erase sizes defined from DT.

Erase regions configuration:

nor->eraseregions[0].erasesize = 4096;
nor->eraseregions[0].numblocks = 8;
nor->eraseregions[0].offset = 0x0;

nor->eraseregions[1].erasesize = 32*1024;
nor->eraseregions[1].numblocks = 1;
nor->eraseregions[1].offset = 32*1024;

nor->eraseregions[2].erasesize = 64*1024;
nor->eraseregions[2].numblocks = div_u64_rem(mtd->size - 64*1024, info->sector_size, &rem);
nor->eraseregions[2].offset = 64*1024;

Device tree (mtd):

partition@0 {
label = "all";
reg = <0x00000000 0x08000000>;
};

partition@1 {
label = "small";
reg = <0x00000000 0x00008000>;
};

partition@2 {
label = "rest"; 
reg = <0x00008000 0x07FF8000>;
};

Logs from startup:

[    1.187722] 0x000000000000-0x000008000000 : "all"
[    1.188498] device: 'mtd0': device_add
[    1.189563] device: 'mtd0ro': device_add
[    1.192359] device: '31:0': device_add
[    1.192810] device: 'mtdblock0': device_add
[    1.194504] 0x000000000000-0x000000008000 : "small"
[    1.195144] device: 'mtd1': device_add
[    1.196667] device: 'mtd1ro': device_add
[    1.198268] device: '31:1': device_add
[    1.199016] device: 'mtdblock1': device_add
[    1.200922] 0x000000008000-0x000008000000 : "rest"
[    1.201222] mtd: partition "rest" doesn't start on an erase block boundary -- force read-only
[    1.201613] device: 'mtd2': device_add
[    1.202541] device: 'mtd2ro': device_add
[    1.204659] device: '31:2': device_add
[    1.206233] device: 'mtdblock2': device_add

Message is from here:
http://lxr.free-electrons.com/source/drivers/mtd/mtdpart.c?v=4.4#L526

Regards,
Marcin

Re: MTD partitions vs erase regions

[Marek Vasut]

On 10/27/2016 02:19 PM, Krzeminski, Marcin (Nokia - PL/Wroclaw) wrote:
> Hi Marek,

Hi,

> I am sending mtd partition and erase regions conflict that I had.
> I admit I have no investigated it, since finally all is different.
> This could make some problems with your idea of having erase sizes defined from DT.

Which flash is that ?

> Erase regions configuration:
> 
> nor->eraseregions[0].erasesize = 4096;
> nor->eraseregions[0].numblocks = 8;
> nor->eraseregions[0].offset = 0x0;
> 
> nor->eraseregions[1].erasesize = 32*1024;
> nor->eraseregions[1].numblocks = 1;
> nor->eraseregions[1].offset = 32*1024;
> 
> nor->eraseregions[2].erasesize = 64*1024;
> nor->eraseregions[2].numblocks = div_u64_rem(mtd->size - 64*1024, info->sector_size, &rem);
> nor->eraseregions[2].offset = 64*1024;
> 
> Device tree (mtd):
> 
> partition@0 {
> label = "all";
> reg = <0x00000000 0x08000000>;
> };
> 
> partition@1 {
> label = "small";
> reg = <0x00000000 0x00008000>;
> };
> 
> partition@2 {
> label = "rest"; 
> reg = <0x00008000 0x07FF8000>;
> };
> 
> Logs from startup:
> 
> [    1.187722] 0x000000000000-0x000008000000 : "all"
> [    1.188498] device: 'mtd0': device_add
> [    1.189563] device: 'mtd0ro': device_add
> [    1.192359] device: '31:0': device_add
> [    1.192810] device: 'mtdblock0': device_add
> [    1.194504] 0x000000000000-0x000000008000 : "small"
> [    1.195144] device: 'mtd1': device_add
> [    1.196667] device: 'mtd1ro': device_add
> [    1.198268] device: '31:1': device_add
> [    1.199016] device: 'mtdblock1': device_add
> [    1.200922] 0x000000008000-0x000008000000 : "rest"
> [    1.201222] mtd: partition "rest" doesn't start on an erase block boundary -- force read-only
> [    1.201613] device: 'mtd2': device_add
> [    1.202541] device: 'mtd2ro': device_add
> [    1.204659] device: '31:2': device_add
> [    1.206233] device: 'mtdblock2': device_add
> 
> Message is from here:
> http://lxr.free-electrons.com/source/drivers/mtd/mtdpart.c?v=4.4#L526
> 
> Regards,
> Marcin
> 


-- 
Best regards,
Marek Vasut

RE: MTD partitions vs erase regions

[Krzeminski, Marcin (Nokia - PL/Wroclaw)]

Marek,

> -----Original Message-----
> From: Marek Vasut [mailto:marex@denx.de]
> Sent: Friday, October 28, 2016 2:15 AM
> To: Krzeminski, Marcin (Nokia - PL/Wroclaw)
> <marcin.krzeminski@nokia.com>
> Cc: linux-mtd@lists.infradead.org
> Subject: Re: MTD partitions vs erase regions
> 
> On 10/27/2016 02:19 PM, Krzeminski, Marcin (Nokia - PL/Wroclaw) wrote:
> > Hi Marek,
> 
> Hi,
> 
> > I am sending mtd partition and erase regions conflict that I had.
> > I admit I have no investigated it, since finally all is different.
> > This could make some problems with your idea of having erase sizes
> defined from DT.
> 
> Which flash is that ?

Sorry - forgot to mention: MT25Q00 (64KiB erase size).
CONFIG_MTD_SPI_NOR_USE_4K_SECTORS is disabled.

Regards,
Marcin
> 
> > Erase regions configuration:
> >
> > nor->eraseregions[0].erasesize = 4096; eraseregions[0].numblocks = 8;
> > nor->eraseregions[0].offset = 0x0;
> >
> > nor->eraseregions[1].erasesize = 32*1024; eraseregions[1].numblocks =
> > nor->1; eraseregions[1].offset = 32*1024;
> >
> > nor->eraseregions[2].erasesize = 64*1024; eraseregions[2].numblocks =
> > nor->div_u64_rem(mtd->size - 64*1024, info->sector_size, &rem);
> > nor->eraseregions[2].offset = 64*1024;
> >
> > Device tree (mtd):
> >
> > partition@0 {
> > label = "all";
> > reg = <0x00000000 0x08000000>;
> > };
> >
> > partition@1 {
> > label = "small";
> > reg = <0x00000000 0x00008000>;
> > };
> >
> > partition@2 {
> > label = "rest";
> > reg = <0x00008000 0x07FF8000>;
> > };
> >
> > Logs from startup:
> >
> > [    1.187722] 0x000000000000-0x000008000000 : "all"
> > [    1.188498] device: 'mtd0': device_add
> > [    1.189563] device: 'mtd0ro': device_add
> > [    1.192359] device: '31:0': device_add
> > [    1.192810] device: 'mtdblock0': device_add
> > [    1.194504] 0x000000000000-0x000000008000 : "small"
> > [    1.195144] device: 'mtd1': device_add
> > [    1.196667] device: 'mtd1ro': device_add
> > [    1.198268] device: '31:1': device_add
> > [    1.199016] device: 'mtdblock1': device_add
> > [    1.200922] 0x000000008000-0x000008000000 : "rest"
> > [    1.201222] mtd: partition "rest" doesn't start on an erase block boundary
> -- force read-only
> > [    1.201613] device: 'mtd2': device_add
> > [    1.202541] device: 'mtd2ro': device_add
> > [    1.204659] device: '31:2': device_add
> > [    1.206233] device: 'mtdblock2': device_add
> >
> > Message is from here:
> > http://lxr.free-electrons.com/source/drivers/mtd/mtdpart.c?v=4.4#L526
> >
> > Regards,
> > Marcin
> >
> 
> 
> --
> Best regards,
> Marek Vasut

Re: MTD partitions vs erase regions

[Marek Vasut]

On 10/28/2016 06:50 AM, Krzeminski, Marcin (Nokia - PL/Wroclaw) wrote:
> Marek,
> 
>> -----Original Message-----
>> From: Marek Vasut [mailto:marex@denx.de]
>> Sent: Friday, October 28, 2016 2:15 AM
>> To: Krzeminski, Marcin (Nokia - PL/Wroclaw)
>> <marcin.krzeminski@nokia.com>
>> Cc: linux-mtd@lists.infradead.org
>> Subject: Re: MTD partitions vs erase regions
>>
>> On 10/27/2016 02:19 PM, Krzeminski, Marcin (Nokia - PL/Wroclaw) wrote:
>>> Hi Marek,
>>
>> Hi,
>>
>>> I am sending mtd partition and erase regions conflict that I had.
>>> I admit I have no investigated it, since finally all is different.
>>> This could make some problems with your idea of having erase sizes
>> defined from DT.
>>
>> Which flash is that ?
> 
> Sorry - forgot to mention: MT25Q00 (64KiB erase size).
> CONFIG_MTD_SPI_NOR_USE_4K_SECTORS is disabled.

I think this is expected then, the subsystem is not ready for device
with variable eraseblock length.

-- 
Best regards,
Marek Vasut