On 31.03.2023 16:18, Arınç ÜNAL wrote:

On 31.03.2023 15:06, Arınç ÜNAL wrote:

quoted

On 31.03.2023 13:16, Daniel Golle wrote:

quoted

On Fri, Mar 31, 2023 at 08:50:28AM +0300, Arınç ÜNAL wrote:

quoted

On 30.03.2023 18:23, Daniel Golle wrote:

quoted

Add driver for the built-in Gigabit Ethernet switch which can be found
in the MediaTek MT7988 SoC.

The switch shares most of its design with MT7530 and MT7531, but has
it's registers mapped into the SoCs register space rather than being
connected externally or internally via MDIO.

Introduce a new platform driver to support that.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
   MAINTAINERS                   |   2 +
   drivers/net/dsa/Kconfig       |  12 ++++
   drivers/net/dsa/Makefile      |   1 +
   drivers/net/dsa/mt7530-mmio.c | 101 
++++++++++++++++++++++++++++++++++
   drivers/net/dsa/mt7530.c      |  86 ++++++++++++++++++++++++++++-
   drivers/net/dsa/mt7530.h      |  12 ++--
   6 files changed, 206 insertions(+), 8 deletions(-)
   create mode 100644 drivers/net/dsa/mt7530-mmio.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 14924aed15ca7..674673dbdfd8b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS

@@ -13174,9 +13174,11 @@ MEDIATEK SWITCH DRIVER

   M:    Sean Wang [off-list ref]
   M:    Landen Chao [off-list ref]
   M:    DENG Qingfang [off-list ref]
+M:    Daniel Golle [off-list ref]
   L:    netdev@vger.kernel.org
   S:    Maintained
   F:    drivers/net/dsa/mt7530-mdio.c
+F:    drivers/net/dsa/mt7530-mmio.c
   F:    drivers/net/dsa/mt7530.*
   F:    net/dsa/tag_mtk.c

diff --git a/drivers/net/dsa/Kconfig b/drivers/net/dsa/Kconfig
index c2551b13324c2..de4d86e37973f 100644
--- a/drivers/net/dsa/Kconfig
+++ b/drivers/net/dsa/Kconfig

@@ -52,6 +52,18 @@ config NET_DSA_MT7530

         Multi-chip module MT7530 in MT7621AT, MT7621DAT, MT7621ST and
         MT7623AI SoCs is supported as well.
+config NET_DSA_MT7988
+    tristate "MediaTek MT7988 built-in Ethernet switch support"
+    select NET_DSA_MT7530_COMMON
+    depends on HAS_IOMEM
+    help
+      This enables support for the built-in Ethernet switch found
+      in the MediaTek MT7988 SoC.
+      The switch is a similar design as MT7531, however, unlike
+      other MT7530 and MT7531 the switch registers are directly
+      mapped into the SoCs register space rather than being 
accessible
+      via MDIO.
+
   config NET_DSA_MV88E6060
       tristate "Marvell 88E6060 ethernet switch chip support"
       select NET_DSA_TAG_TRAILER

diff --git a/drivers/net/dsa/Makefile b/drivers/net/dsa/Makefile
index 71250d7dd41af..103a33e20de4b 100644
--- a/drivers/net/dsa/Makefile
+++ b/drivers/net/dsa/Makefile

@@ -8,6 +8,7 @@ endif

   obj-$(CONFIG_NET_DSA_LANTIQ_GSWIP) += lantiq_gswip.o
   obj-$(CONFIG_NET_DSA_MT7530_COMMON) += mt7530.o
   obj-$(CONFIG_NET_DSA_MT7530)    += mt7530-mdio.o
+obj-$(CONFIG_NET_DSA_MT7988)    += mt7530-mmio.o

I'm not fond of this way. Wouldn't it be better if we split the mdio 
and
mmio drivers to separate modules and kept switch hardware support on
mt7530.c?

You mean this in terms of Kconfig symbols?
Because the way you describe is basically what I'm doing here:
  * mt7530.c is the shared/common switch hardware driver
  * mt7530-mdio.c contains the MDIO accessors and MDIO device drivers 
for
    MT7530, MT7531, MT7621, MT7623, ...
  * mt7530-mmio.c contains the platform device driver for in-SoC 
switches
    which are accessed via MMIO, ie. MT7988 (and yes, this could be
    extended to also support MT7620A/N).

Ok great.

quoted

In early drafts I also named the Kconfig symbols
CONFIG_NET_DSA_MT7530 for mt7530.c (ie. the common part)
CONFIG_NET_DSA_MT7530_MDIO for the MDIO driver
CONFIG_NET_DSA_MT7530_MMIO for the MMIO driver

However, as existing kernel configurations expect 
CONFIG_NET_DSA_MT7530 to
select the MDIO driver, I decided it would be better to hide the 
symbol of
the common part and have CONFIG_NET_DSA_MT7530 select the MDIO driver 
like
it was before.

You can "imply NET_DSA_MT7530_MDIO" from NET_DSA_MT7530 so the MDIO 
driver is also enabled when NET_DSA_MT7530 is selected. For example, 
on Realtek, both MDIO and SMI drivers are enabled by default when 
either of the main drivers are selected.

config NET_DSA_MT7530
     tristate "MediaTek MT7530 and MT7531 Ethernet switch support"
     select NET_DSA_TAG_MTK
     select MEDIATEK_GE_PHY
     select PCS_MTK_LYNXI
     imply NET_DSA_MT7530_MDIO
     imply NET_DSA_MT7530_MMIO

The final kconfig should look like this:

config NET_DSA_MT7530
     tristate "MediaTek MT7530 and MT7531 Ethernet switch support"
     select NET_DSA_TAG_MTK
     select MEDIATEK_GE_PHY
     select PCS_MTK_LYNXI

Looks like PCS_MTK_LYNXI is used on NET_DSA_MT7530_MDIO instead now. I 
also see '#include <linux/pcs/pcs-mtk-lynxi.h>' on mt7530.c but don't 
see any functions called on it. Leftover?

     imply NET_DSA_MT7530_MDIO
     imply NET_DSA_MT7530_MMIO
     help
       This enables support for the MediaTek MT7530 and MT7531 Ethernet
       switch chips. Multi-chip module MT7530 in MT7621AT, MT7621DAT,
       MT7621ST and MT7623AI SoCs, and built-in switch in MT7688 SoC is
       supported.

config NET_DSA_MT7530_MDIO
     tristate "MediaTek MT7530 MDIO interface driver"

Should go here:

select PCS_MTK_LYNXI

Arınç