Re: b53 tags on bpi-r1 (bcm53125)

[Florian Fainelli <f.fainelli@gmail.com>]

Hi Jochen,

On 11/21/2017 12:10 AM, Jochen Friedrich wrote:
> Hi Florian,
> 
> 
> i just tested the latest DSA patches for b53 on a bpi-r1 device (net:
> dsa: b53: Turn on Broadcom tags).
> 
> Unfortunately, the bcm53125 does not seem to handle the broadcom tags on
> CPU port although tuned on b53_brcm_hdr_setup(). The tag is still
> visible on a device connected to one of the switch ports.
> 
> I wonder if there is something else necessary to make the chip handle
> the tags or if the chip doesn't support broadcom tags after all. The
> documentation at
> https://sourceforge.net/p/ohvesw/svn/12/tree/document/bcm/53125U-DS02-R.pdf
> doesn't document register 3 in the management page, at all...

I am afraid U stands for unmanaged, which means we may not have any
possibility to enable Broadcom tags on that particular model. And you
are right, I also don't see any Broadcom HDR control register in the
datasheet, only the 53125M and S seem to have that, darn.

Does the following patch help at all (I don't really expect it to)?
Could you also provide me with two piieces of information that could
help detect such a switch model:

- what is the value of the revision register (should be printed along
with BCM53125 during boot)?
- what is the value of page 02, register 3 during b53_switch_detect()? A
managed switch should have this set to 0x3, whereas I would expect an
unmanaged switch to be 0x0

Thanks!

@@ -330,9 +331,9 @@ static void b53_set_forwarding(struct b53_device
*dev, int enable)
        b53_read8(dev, B53_CTRL_PAGE, B53_SWITCH_MODE, &mgmt);

        if (enable)
-               mgmt |= SM_SW_FWD_EN;
+               mgmt |= SM_SW_FWD_EN | SM_SW_FWD_MODE;
        else
-               mgmt &= ~SM_SW_FWD_EN;
+               mgmt &= ~(SM_SW_FWD_EN | SM_SW_FWD_MODE);

        b53_write8(dev, B53_CTRL_PAGE, B53_SWITCH_MODE, mgmt);


-- 
Florian