[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20201219194831.5mjlmjfbcpggrh45@skbuf>
Date: Sat, 19 Dec 2020 21:48:31 +0200
From: Vladimir Oltean <olteanv@...il.com>
To: Florian Fainelli <f.fainelli@...il.com>
Cc: Andrew Lunn <andrew@...n.ch>, DENG Qingfang <dqfext@...il.com>,
netdev@...r.kernel.org, linux-mediatek@...ts.infradead.org,
Sean Wang <sean.wang@...iatek.com>,
Landen Chao <Landen.Chao@...iatek.com>,
Vivien Didelot <vivien.didelot@...il.com>,
"David S . Miller" <davem@...emloft.net>,
Jakub Kicinski <kuba@...nel.org>,
Matthias Brugger <matthias.bgg@...il.com>,
Russell King <linux@...linux.org.uk>,
Greg Ungerer <gerg@...nel.org>,
Rene van Dorst <opensource@...rst.com>,
John Crispin <john@...ozen.org>
Subject: Re: [RFC PATCH net-next] net: dsa: mt7530: rename MT7621 compatible
Hi Andrew, Florian,
On Sat, Dec 19, 2020 at 09:07:13AM -0800, Florian Fainelli wrote:
> On 12/19/2020 8:26 AM, Andrew Lunn wrote:
> >> --- a/drivers/net/dsa/mt7530.c
> >> +++ b/drivers/net/dsa/mt7530.c
> >> @@ -2688,7 +2688,7 @@ static const struct mt753x_info mt753x_table[] = {
> >> };
> >>
> >> static const struct of_device_id mt7530_of_match[] = {
> >> - { .compatible = "mediatek,mt7621", .data = &mt753x_table[ID_MT7621], },
> >> + { .compatible = "mediatek,mt7621-gsw", .data = &mt753x_table[ID_MT7621], },
> >> { .compatible = "mediatek,mt7530", .data = &mt753x_table[ID_MT7530], },
> >> { .compatible = "mediatek,mt7531", .data = &mt753x_table[ID_MT7531], },
> >> { /* sentinel */ },
> >
> > This will break backwards compatibility with existing DT blobs. You
> > need to keep the old "mediatek,mt7621", but please add a comment that
> > it is deprecated.
>
> Besides, adding -gsw would make it inconsistent with the existing
> matching compatible strings. While it's not ideal to have the same
> top-level SoC compatible and having another sub-node within that SoC's
> DTS have the same compatible, given this would be break backwards
> compatibility, cannot you stay with what is defined today?
The MT7621 device tree is in staging. I suppose that some amount of
breaking changes could be tolerated?
But Qingfang, I'm confused when looking at drivers/staging/mt7621-dts/mt7621.dtsi.
/ethernet@...00000/mdio-bus {
switch0: switch0@0 {
compatible = "mediatek,mt7621";
#address-cells = <1>;
#size-cells = <0>;
reg = <0>;
mediatek,mcm;
resets = <&rstctrl 2>;
reset-names = "mcm";
ports {
#address-cells = <1>;
#size-cells = <0>;
reg = <0>;
port@0 {
status = "off";
reg = <0>;
label = "lan0";
};
port@1 {
status = "off";
reg = <1>;
label = "lan1";
};
port@2 {
status = "off";
reg = <2>;
label = "lan2";
};
port@3 {
status = "off";
reg = <3>;
label = "lan3";
};
port@4 {
status = "off";
reg = <4>;
label = "lan4";
};
port@6 {
reg = <6>;
label = "cpu";
ethernet = <&gmac0>;
phy-mode = "trgmii";
fixed-link {
speed = <1000>;
full-duplex;
};
};
};
};
};
/ {
gsw: gsw@...10000 {
compatible = "mediatek,mt7621-gsw";
reg = <0x1e110000 0x8000>;
interrupt-parent = <&gic>;
interrupts = <GIC_SHARED 23 IRQ_TYPE_LEVEL_HIGH>;
};
};
What is the platform device at the memory address 1e110000?
There is no driver for it. The documentation only has me even more
confused:
Mediatek Gigabit Switch
=======================
The mediatek gigabit switch can be found on Mediatek SoCs (mt7620, mt7621).
Required properties:
- compatible: Should be "mediatek,mt7620-gsw" or "mediatek,mt7621-gsw"
- reg: Address and length of the register set for the device
- interrupts: Should contain the gigabit switches interrupt
- resets: Should contain the gigabit switches resets
- reset-names: Should contain the reset names "gsw"
Example:
gsw@...10000 {
compatible = "ralink,mt7620-gsw"; <- notice how even the example is bad and inconsistent
reg = <0x10110000 8000>;
resets = <&rstctrl 23>;
reset-names = "gsw";
interrupt-parent = <&intc>;
interrupts = <17>;
};
Does the MT7621 contain two Ethernet switches, one accessed over MMIO
and another over MDIO? Or is it the same switch? I don't understand.
What is the relationship between the new compatible that you're
proposing, Qingfang, and the existing device tree bindings?
Powered by blists - more mailing lists