Re: [PATCH 02/14] drivers: net: dsa: qca8k: tweak internal delay to oem spec

From: Florian Fainelli
Date: Thu Apr 22 2021 - 21:58:21 EST




On 4/22/2021 6:57 PM, Ansuel Smith wrote:
> On Thu, Apr 22, 2021 at 06:53:45PM -0700, Florian Fainelli wrote:
>>
>>
>> On 4/22/2021 6:47 PM, Ansuel Smith wrote:
>>> The original code had the internal dalay set to 1 for tx and 2 for rx.
>>> Apply the oem internal dalay to fix some switch communication error.
>>>
>>> Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx>
>>> ---
>>> drivers/net/dsa/qca8k.c | 6 ++++--
>>> drivers/net/dsa/qca8k.h | 9 ++++-----
>>> 2 files changed, 8 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
>>> index a6d35b825c0e..b8bfc7acf6f4 100644
>>> --- a/drivers/net/dsa/qca8k.c
>>> +++ b/drivers/net/dsa/qca8k.c
>>> @@ -849,8 +849,10 @@ qca8k_phylink_mac_config(struct dsa_switch *ds, int port, unsigned int mode,
>>> */
>>> qca8k_write(priv, reg,
>>> QCA8K_PORT_PAD_RGMII_EN |
>>> - QCA8K_PORT_PAD_RGMII_TX_DELAY(QCA8K_MAX_DELAY) |
>>> - QCA8K_PORT_PAD_RGMII_RX_DELAY(QCA8K_MAX_DELAY));
>>> + QCA8K_PORT_PAD_RGMII_TX_DELAY(1) |
>>> + QCA8K_PORT_PAD_RGMII_RX_DELAY(2) |
>>> + QCA8K_PORT_PAD_RGMII_TX_DELAY_EN |
>>> + QCA8K_PORT_PAD_RGMII_RX_DELAY_EN);
>>
>> There are standard properties in order to configure a specific RX and TX
>> delay:
>>
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/net/ethernet-controller.yaml#n125
>>
>> can you use that mechanism and parse that property, or if nothing else,
>> allow an user to override delays via device tree using these standard
>> properties?
>
> Since this is mac config, what would be the best way to parse these
> data? Parse them in the qca8k_setup and put them in the
> qca8k_priv?

Yes something like that would work.
--
Florian