[RFC][PATCH] bcmai: introduce AI driver

Rafał Miłecki zajec5 at gmail.com
Fri Apr 8 13:27:11 EDT 2011

2011/4/8 Arend van Spriel <arend at broadcom.com>:
> On Fri, 08 Apr 2011 18:56:13 +0200, Rafał Miłecki <zajec5 at gmail.com> wrote:
>> 2011/4/6 Arend van Spriel <arend at broadcom.com>:
>>> 3. Device identification
>>> The cores are identified by manufacturer, core id and revision in your
>>> patch. I would not use the revision because 4 out of 5 times a revision
>>> change does indicate a hardware change but no change in programming
>>> interface. The enumeration data does contain a more selective field
>>> indicating the core class (4 bits following the core identifier). I
>>> suggest
>>> to replace the revision field by this class field.
>> Could you say something more about *class*, please? For my BCM43224 it
>> seems to be 0x0. WIll check BCM4313 in a moment.
> In principal the manufacturer id is unique (defined/assigned by JEDEC
> www.jedec.org) and the chip id and chip class are defined by the
> manufacturer. So I can only indicate what classes Broadcom uses in
> combination with the manufacturer id BRCM, ARM and MIPS.
> /* Component Classes */
> #define CC_SIM                  0
> #define CC_EROM                 1
> #define CC_CORESIGHT            9
> #define CC_VERIF                0xb
> #define CC_OPTIMO               0xd
> #define CC_GEN                  0xe
> #define CC_PRIMECELL            0xf
> Looking at this it seems strange that you see a class value of 0x0. It may
> be rarely used or for non-production chips only (for simulation, chip
> bringup) which may require additional (debug) functions. So question is
> whether you will need it, but it is specified by ARM and it is up to
> manufacturers to use it. So I it is better to be safe than sorry and have
> this in the device id.

OK, thanks. I'm compiling kernel with patch V2 right now. Of course
class included.


More information about the linux-arm-kernel mailing list