Re: [PATCH net-next 05/13] net: dsa: sja1105: add a PHY interface type compatibility matrix

On Mon, May 24, 2021 at 07:23:09PM -0700, Florian Fainelli wrote:

On 5/24/2021 4:22 PM, Vladimir Oltean wrote:

quoted

From: Vladimir Oltean <vladimir.oltean@nxp.com>

On the SJA1105, all ports support the parallel "xMII" protocols (MII,
RMII, RGMII) except for port 4 on SJA1105R/S which supports only SGMII.
This was relatively easy to model, by special-casing the SGMII port.

On the SJA1110, certain ports can be pinmuxed between SGMII and xMII, or
between SGMII and an internal 100base-TX PHY. This creates problems,
because the driver's assumption so far was that if a port supports
SGMII, it uses SGMII.

We allow the device tree to tell us how the port pinmuxing is done, and
check that against a PHY interface type compatibility matrix for
plausibility.

The other big change is that instead of doing SGMII configuration based
on what the port supports, we do it based on what is the configured
phy_mode of the port.

The 2500base-x support added in this patch is not complete.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 drivers/net/dsa/sja1105/sja1105.h      |  5 +++
 drivers/net/dsa/sja1105/sja1105_main.c | 59 +++++++++++++-------------
 drivers/net/dsa/sja1105/sja1105_spi.c  | 20 +++++++++
 3 files changed, 55 insertions(+), 29 deletions(-)

diff --git a/drivers/net/dsa/sja1105/sja1105.h b/drivers/net/dsa/sja1105/sja1105.h
index d5c0217b1f65..a27841642693 100644
--- a/drivers/net/dsa/sja1105/sja1105.h
+++ b/drivers/net/dsa/sja1105/sja1105.h

@@ -111,6 +111,11 @@ struct sja1105_info {
 				enum packing_op op);
 	int (*clocking_setup)(struct sja1105_private *priv);
 	const char *name;
+	bool supports_mii[SJA1105_MAX_NUM_PORTS];
+	bool supports_rmii[SJA1105_MAX_NUM_PORTS];
+	bool supports_rgmii[SJA1105_MAX_NUM_PORTS];
+	bool supports_sgmii[SJA1105_MAX_NUM_PORTS];
+	bool supports_2500basex[SJA1105_MAX_NUM_PORTS];

If you used a bitmap you may be able to play some nice tricks with
ordering them in PHY_INTERFACE_MODE_* order and just increment a pointer
to the bitmap.

Since it looks like all of the chips support MII, RMII, and RGMII on all
ports, maybe you can specify only those that don't?

Still:

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>

Because the SJA1110 doesn't have public documentation, I am making a bit
of a compromise for SJA1105 in order to be very clear about which SJA1110
port supports which PHY interface type. With pointers to the beginning
and end of a phy_interface_t array for each switch type and port number,
it wouldn't be quite as clear, in fact it might end up quite a bit
messy.