Re: [PATCH 2/3] m68k/q40: add data_swab option for pata_falcon to byte-swap disk data

[Sergei Shtylyov <sergei.shtylyov@gmail.com>]

Hello!

On 8/20/23 10:27 PM, Michael Schmitz wrote:
[...]

> thanks for reviewing - this has mostly been addressed in v2 or v3 (which I forgot to send to you, sorry). Damien asked for the patch title to be changed (now 'ata: pata_falcon: add data_swab option to byte-swap disk data) so you might have missed it on the list.

   I didn't want to repeat such request after him. :-)
   I'm subscribed to linux-ide thru my Gmail account, and I'm still not seeing
your further patch versions on the list... :-/

[...]

>>> Some users of pata_falcon on Q40 have IDE disks in default
>>> IDE little endian byte order, whereas legacy disks use
>>> host-native big-endian byte order as on the Atari Falcon.
>>>
>>> Add module parameter 'data_swab' to allow connecting drives
>>> with non-native data byte order. Drives selected by the
>>> data_swap bit mask will have their user data byte-swapped to
>>> host byte order, i.e. 'pata_falcon.data_swab=2' will byte-swap
>>> all user data on drive B, leaving data on drive A in native
>>> byte order. On Q40, drives on a second IDE interface may be
>>> added to the bit mask as bits 2 and 3.
>>>
>>> Default setting is no byte swapping, i.e. compatibility with
>>> the native Falcon or Q40 operating system disk format.
>>>
>>> Cc: William R Sowerbutts <will@sowerbutts.com>
>>> Cc: Finn Thain <fthain@linux-m68k.org>
>>> Cc: Geert Uytterhoeven <geert@linux-m68k.org>
>>> Signed-off-by: Michael Schmitz <schmitzmic@gmail.com>

[...]

>>> diff --git a/drivers/ata/pata_falcon.c b/drivers/ata/pata_falcon.c
>>> index 346259e3bbc8..90488f565d6f 100644
>>> --- a/drivers/ata/pata_falcon.c
>>> +++ b/drivers/ata/pata_falcon.c
>>> @@ -33,6 +33,16 @@
>>>   #define DRV_NAME "pata_falcon"
>>>   #define DRV_VERSION "0.1.0"
>>>   +static int pata_falcon_swap_mask;
>>> +
>>> +module_param_named(data_swab, pata_falcon_swap_mask, int, 0444);
>>> +MODULE_PARM_DESC(data_swab, "Data byte swap enable/disable bitmap (0x1==drive1, 0x2==drive2, 0x4==drive3, 0x8==drive4, default==0)");
>>     Hm, Greg KH keeps saying us that the module parameters belong to '90s. :-)

> What else can I use that would allow setting a driver parameter at boot time? This driver will be built-in pretty much all the time.

   I guess he means sysfs...

[...]

MBR, Sergey