Use DELAY_ENABLE macro for RK3328, RK3566/RK3568 and RK3588

[PATCH 1/3] net: stmmac: dwmac-rk: Use DELAY_ENABLE macro for RK3328

Posted by Jonas Karlman 11 months, 1 week ago

Support for Rockchip RK3328 GMAC and addition of the DELAY_ENABLE macro
was merged in the same merge window. This resulted in RK3328 not being
converted to use the new DELAY_ENABLE macro.

Change to use the DELAY_ENABLE macro to help disable MAC delay when
RGMII_ID/RXID/TXID is used.

Fixes: eaf70ad14cbb ("net: stmmac: dwmac-rk: Add handling for RGMII_ID/RXID/TXID")
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
index 003fa5cf42c3..297fa93e4a39 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
@@ -593,8 +593,7 @@ static void rk3328_set_to_rgmii(struct rk_priv_data *bsp_priv,
 	regmap_write(bsp_priv->grf, RK3328_GRF_MAC_CON1,
 		     RK3328_GMAC_PHY_INTF_SEL_RGMII |
 		     RK3328_GMAC_RMII_MODE_CLR |
-		     RK3328_GMAC_RXCLK_DLY_ENABLE |
-		     RK3328_GMAC_TXCLK_DLY_ENABLE);
+		     DELAY_ENABLE(RK3328, tx_delay, rx_delay));
 
 	regmap_write(bsp_priv->grf, RK3328_GRF_MAC_CON0,
 		     RK3328_GMAC_CLK_RX_DL_CFG(rx_delay) |
-- 
2.48.1

Re: [PATCH 1/3] net: stmmac: dwmac-rk: Use DELAY_ENABLE macro for RK3328

Posted by Andrew Lunn 11 months, 1 week ago

On Thu, Mar 06, 2025 at 08:38:52PM +0000, Jonas Karlman wrote:
> Support for Rockchip RK3328 GMAC and addition of the DELAY_ENABLE macro
> was merged in the same merge window. This resulted in RK3328 not being
> converted to use the new DELAY_ENABLE macro.
> 
> Change to use the DELAY_ENABLE macro to help disable MAC delay when
> RGMII_ID/RXID/TXID is used.
> 
> Fixes: eaf70ad14cbb ("net: stmmac: dwmac-rk: Add handling for RGMII_ID/RXID/TXID")

Please add a description of the broken behaviour. How would i know i
need this fix? What would i see?

We also need to be careful with backwards compatibility. Is there the
potential for double bugs cancelling each other out? A board which has
the wrong phy-mode in DT, but because of this bug, the wrong register
is written and it actually works because of reset defaults?

    Andrew

---
pw-bot: cr

Re: [PATCH 1/3] net: stmmac: dwmac-rk: Use DELAY_ENABLE macro for RK3328

Posted by Jonas Karlman 11 months, 1 week ago

Hi Andrew,

On 2025-03-06 23:25, Andrew Lunn wrote:
> On Thu, Mar 06, 2025 at 08:38:52PM +0000, Jonas Karlman wrote:
>> Support for Rockchip RK3328 GMAC and addition of the DELAY_ENABLE macro
>> was merged in the same merge window. This resulted in RK3328 not being
>> converted to use the new DELAY_ENABLE macro.
>>
>> Change to use the DELAY_ENABLE macro to help disable MAC delay when
>> RGMII_ID/RXID/TXID is used.
>>
>> Fixes: eaf70ad14cbb ("net: stmmac: dwmac-rk: Add handling for RGMII_ID/RXID/TXID")
> 
> Please add a description of the broken behaviour. How would i know i
> need this fix? What would i see?

Based on my layman testing I have not seen any real broken behaviour
with current enablement of a zero rx/tx MAC delay for RGMII_ID/RXID/TXID.

The driver ops is called with a rx/tx_delay=0 for RGMII_ID/RXID/TXID
modes, what the MAC does with enable=true and rx/tx_delay=0 is unclear
to me.

> 
> We also need to be careful with backwards compatibility. Is there the
> potential for double bugs cancelling each other out? A board which has
> the wrong phy-mode in DT, but because of this bug, the wrong register
> is written and it actually works because of reset defaults?

To my knowledge this should have very limited effect, however I am no
network expert and after doing very basic testing on several different
rk3328/rk3566/rk3568/rk3588 I could not see any real affect with/without
this change.

The use of Fixes-tag was more to have a reference to the commit that
first should have used the DELAY_ENABLE macro.

Regards,
Jonas

> 
>     Andrew
> 
> ---
> pw-bot: cr
> 
> _______________________________________________
> Linux-rockchip mailing list
> Linux-rockchip@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-rockchip

Re: [PATCH 1/3] net: stmmac: dwmac-rk: Use DELAY_ENABLE macro for RK3328

Posted by Andrew Lunn 11 months, 1 week ago

On Fri, Mar 07, 2025 at 12:28:42AM +0100, Jonas Karlman wrote:
> Hi Andrew,
> 
> On 2025-03-06 23:25, Andrew Lunn wrote:
> > On Thu, Mar 06, 2025 at 08:38:52PM +0000, Jonas Karlman wrote:
> >> Support for Rockchip RK3328 GMAC and addition of the DELAY_ENABLE macro
> >> was merged in the same merge window. This resulted in RK3328 not being
> >> converted to use the new DELAY_ENABLE macro.
> >>
> >> Change to use the DELAY_ENABLE macro to help disable MAC delay when
> >> RGMII_ID/RXID/TXID is used.
> >>
> >> Fixes: eaf70ad14cbb ("net: stmmac: dwmac-rk: Add handling for RGMII_ID/RXID/TXID")
> > 
> > Please add a description of the broken behaviour. How would i know i
> > need this fix? What would i see?
> 
> Based on my layman testing I have not seen any real broken behaviour
> with current enablement of a zero rx/tx MAC delay for RGMII_ID/RXID/TXID.
> 
> The driver ops is called with a rx/tx_delay=0 for RGMII_ID/RXID/TXID
> modes, what the MAC does with enable=true and rx/tx_delay=0 is unclear
> to me.
> 
> > 
> > We also need to be careful with backwards compatibility. Is there the
> > potential for double bugs cancelling each other out? A board which has
> > the wrong phy-mode in DT, but because of this bug, the wrong register
> > is written and it actually works because of reset defaults?
> 
> To my knowledge this should have very limited effect, however I am no
> network expert and after doing very basic testing on several different
> rk3328/rk3566/rk3568/rk3588 I could not see any real affect with/without
> this change.
> 
> The use of Fixes-tag was more to have a reference to the commit that
> first should have used the DELAY_ENABLE macro.

https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html

  It must either fix a real bug that bothers people or just add a device ID.

It does not sound like this meets the stable requirements. Plus there
is the potential for breakage. So i suggest you drop the Fixes: tag
and we merge this via net-next.

Please take a look at:

https://www.kernel.org/doc/html/latest/process/maintainer-netdev.html

    Andrew

---
pw-bot: cr

Re: [PATCH 1/3] net: stmmac: dwmac-rk: Use DELAY_ENABLE macro for RK3328

Posted by Dragan Simic 11 months, 1 week ago

Hello Jonas,

On 2025-03-06 21:38, Jonas Karlman wrote:
> Support for Rockchip RK3328 GMAC and addition of the DELAY_ENABLE macro
> was merged in the same merge window. This resulted in RK3328 not being
> converted to use the new DELAY_ENABLE macro.
> 
> Change to use the DELAY_ENABLE macro to help disable MAC delay when
> RGMII_ID/RXID/TXID is used.
> 
> Fixes: eaf70ad14cbb ("net: stmmac: dwmac-rk: Add handling for
> RGMII_ID/RXID/TXID")
> Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
> ---
>  drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> index 003fa5cf42c3..297fa93e4a39 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> @@ -593,8 +593,7 @@ static void rk3328_set_to_rgmii(struct
> rk_priv_data *bsp_priv,
>  	regmap_write(bsp_priv->grf, RK3328_GRF_MAC_CON1,
>  		     RK3328_GMAC_PHY_INTF_SEL_RGMII |
>  		     RK3328_GMAC_RMII_MODE_CLR |
> -		     RK3328_GMAC_RXCLK_DLY_ENABLE |
> -		     RK3328_GMAC_TXCLK_DLY_ENABLE);
> +		     DELAY_ENABLE(RK3328, tx_delay, rx_delay));
> 
>  	regmap_write(bsp_priv->grf, RK3328_GRF_MAC_CON0,
>  		     RK3328_GMAC_CLK_RX_DL_CFG(rx_delay) |

Thanks for this patch...  It's looking good to me, and good job
spotting this issue!  Please, feel free to include:

Reviewed-by: Dragan Simic <dsimic@manjaro.org>