[PATCH net-next v5 0/2] net: dsa: microchip: enable setting rmii reference

[PATCH net-next v5 0/2] net: dsa: microchip: enable setting rmii reference

[Ante Knezic]

KSZ88X3 devices can select between internal and external RMII reference clock.
This patch series introduces new device tree property for setting reference
clock to internal.

---
V5:
  - move rmii-clk-internal to be a port device tree property.
V4:
  - remove rmii_clk_internal from ksz_device, as its not needed any more
  - move rmii clk config as well as ksz8795_cpu_interface_select to 
    ksz8_config_cpu_port
V3: 
  - move ksz_cfg from global switch config to port config as suggested by Vladimir
    Oltean
  - reverse patch order as suggested by Vladimir Oltean
  - adapt dt schema as suggested by Conor Dooley
V2: 
  - don't rely on default register settings - enforce set/clear property as
    suggested by Andrew Lunn
  - enforce dt schema as suggested by Conor Dooley

Ante Knezic (2):
  dt-bindings: net: microchip,ksz: document microchip,rmii-clk-internal
  net: dsa: microchip: add property to select internal RMII reference
    clock

 .../devicetree/bindings/net/dsa/microchip,ksz.yaml | 38 ++++++++++++++-
 drivers/net/dsa/microchip/ksz8795.c                | 56 +++++++++++++++++++---
 drivers/net/dsa/microchip/ksz8795_reg.h            |  3 ++
 3 files changed, 90 insertions(+), 7 deletions(-)

-- 
2.11.0

[PATCH net-next v5 1/2] dt-bindings: net: microchip,ksz: document microchip,rmii-clk-internal

[Ante Knezic]

Add documentation for selecting reference rmii clock on KSZ88X3 devices
Signed-off-by: Ante Knezic <ante.knezic@helmholz.de>
---
 .../devicetree/bindings/net/dsa/microchip,ksz.yaml | 38 +++++++++++++++++++++-
 1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml b/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml
index b3029c64d0d5..3cebb9c9b1c8 100644
--- a/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml
+++ b/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml
@@ -11,7 +11,6 @@ maintainers:
   - Woojung Huh <Woojung.Huh@microchip.com>
 
 allOf:
-  - $ref: dsa.yaml#/$defs/ethernet-ports
   - $ref: /schemas/spi/spi-peripheral-props.yaml#
 
 properties:
@@ -78,6 +77,43 @@ required:
   - compatible
   - reg
 
+if:
+  not:
+    properties:
+      compatible:
+        enum:
+          - microchip,ksz8863
+          - microchip,ksz8873
+then:
+  $ref: dsa.yaml#/$defs/ethernet-ports
+else:
+  patternProperties:
+    "^(ethernet-)?ports$":
+      patternProperties:
+        "^(ethernet-)?port@[0-2]$":
+          $ref: dsa-port.yaml#
+          properties:
+            microchip,rmii-clk-internal:
+              $ref: /schemas/types.yaml#/definitions/flag
+              description:
+	        When ksz88x3 is acting as clock provier (via REFCLKO) it
+		can select between internal and external RMII reference
+		clock. Internal reference clock means that the clock for
+		the RMII of ksz88x3 is provided by the ksz88x3 internally
+		and the REFCLKI pin is unconnected. For the external
+		reference clock, the clock needs to be fed back to ksz88x3
+		via REFCLKI.
+		If microchip,rmii-clk-internal is set, ksz88x3 will provide
+		rmii reference clock internally, otherwise reference clock
+		should be provided externally.
+          if:
+            not:
+              required: [ ethernet ]
+          then:
+            properties:
+              microchip,rmii-clk-internal: false
+          unevaluatedProperties: false
+
 unevaluatedProperties: false
 
 examples:
-- 
2.11.0

Re: [PATCH net-next v5 1/2] dt-bindings: net: microchip,ksz: document microchip,rmii-clk-internal

[kernel test robot]

Hi Ante,

kernel test robot noticed the following build warnings:

[auto build test WARNING on net-next/main]

url:    https://github.com/intel-lab-lkp/linux/commits/Ante-Knezic/dt-bindings-net-microchip-ksz-document-microchip-rmii-clk-internal/20231125-000625
base:   net-next/main
patch link:    https://lore.kernel.org/r/0ea1db6b2f2e93c3531645f98888775a4d3165d4.1700841353.git.ante.knezic%40helmholz.de
patch subject: [PATCH net-next v5 1/2] dt-bindings: net: microchip,ksz: document microchip,rmii-clk-internal
compiler: loongarch64-linux-gcc (GCC) 13.2.0
reproduce: (https://download.01.org/0day-ci/archive/20231125/202311250528.gG5FVdW6-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202311250528.gG5FVdW6-lkp@intel.com/

dtcheck warnings: (new ones prefixed by >>)
>> Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml:99:1: [error] syntax error: found character '\t' that cannot start any token (syntax)
--
>> Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml:99:1: found character that cannot start any token
--
>> Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml: ignoring, error parsing file

vim +99 Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml

     8	
     9	maintainers:
    10	  - Marek Vasut <marex@denx.de>
    11	  - Woojung Huh <Woojung.Huh@microchip.com>
    12	
    13	allOf:
    14	  - $ref: /schemas/spi/spi-peripheral-props.yaml#
    15	
    16	properties:
    17	  # See Documentation/devicetree/bindings/net/dsa/dsa.yaml for a list of additional
    18	  # required and optional properties.
    19	  compatible:
    20	    enum:
    21	      - microchip,ksz8765
    22	      - microchip,ksz8794
    23	      - microchip,ksz8795
    24	      - microchip,ksz8863
    25	      - microchip,ksz8873
    26	      - microchip,ksz9477
    27	      - microchip,ksz9897
    28	      - microchip,ksz9896
    29	      - microchip,ksz9567
    30	      - microchip,ksz8565
    31	      - microchip,ksz9893
    32	      - microchip,ksz9563
    33	      - microchip,ksz8563
    34	
    35	  reset-gpios:
    36	    description:
    37	      Should be a gpio specifier for a reset line.
    38	    maxItems: 1
    39	
    40	  wakeup-source: true
    41	
    42	  microchip,synclko-125:
    43	    $ref: /schemas/types.yaml#/definitions/flag
    44	    description:
    45	      Set if the output SYNCLKO frequency should be set to 125MHz instead of 25MHz.
    46	
    47	  microchip,synclko-disable:
    48	    $ref: /schemas/types.yaml#/definitions/flag
    49	    description:
    50	      Set if the output SYNCLKO clock should be disabled. Do not mix with
    51	      microchip,synclko-125.
    52	
    53	  microchip,io-drive-strength-microamp:
    54	    description:
    55	      IO Pad Drive Strength
    56	    enum: [8000, 16000]
    57	    default: 16000
    58	
    59	  microchip,hi-drive-strength-microamp:
    60	    description:
    61	      High Speed Drive Strength. Controls drive strength of GMII / RGMII /
    62	      MII / RMII (except TX_CLK/REFCLKI, COL and CRS) and CLKO_25_125 lines.
    63	    enum: [2000, 4000, 8000, 12000, 16000, 20000, 24000, 28000]
    64	    default: 24000
    65	
    66	  microchip,lo-drive-strength-microamp:
    67	    description:
    68	      Low Speed Drive Strength. Controls drive strength of TX_CLK / REFCLKI,
    69	      COL, CRS, LEDs, PME_N, NTRP_N, SDO and SDI/SDA/MDIO lines.
    70	    enum: [2000, 4000, 8000, 12000, 16000, 20000, 24000, 28000]
    71	    default: 8000
    72	
    73	  interrupts:
    74	    maxItems: 1
    75	
    76	required:
    77	  - compatible
    78	  - reg
    79	
    80	if:
    81	  not:
    82	    properties:
    83	      compatible:
    84	        enum:
    85	          - microchip,ksz8863
    86	          - microchip,ksz8873
    87	then:
    88	  $ref: dsa.yaml#/$defs/ethernet-ports
    89	else:
    90	  patternProperties:
    91	    "^(ethernet-)?ports$":
    92	      patternProperties:
    93	        "^(ethernet-)?port@[0-2]$":
    94	          $ref: dsa-port.yaml#
    95	          properties:
    96	            microchip,rmii-clk-internal:
    97	              $ref: /schemas/types.yaml#/definitions/flag
    98	              description:
  > 99		        When ksz88x3 is acting as clock provier (via REFCLKO) it
   100			can select between internal and external RMII reference
   101			clock. Internal reference clock means that the clock for
   102			the RMII of ksz88x3 is provided by the ksz88x3 internally
   103			and the REFCLKI pin is unconnected. For the external
   104			reference clock, the clock needs to be fed back to ksz88x3
   105			via REFCLKI.
   106			If microchip,rmii-clk-internal is set, ksz88x3 will provide
   107			rmii reference clock internally, otherwise reference clock
   108			should be provided externally.
   109	          if:
   110	            not:
   111	              required: [ ethernet ]
   112	          then:
   113	            properties:
   114	              microchip,rmii-clk-internal: false
   115	          unevaluatedProperties: false
   116	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

[PATCH net-next v5 2/2] net: dsa: microchip: add property to select internal RMII reference clock

[Ante Knezic]

Microchip KSZ8863/KSZ8873 have the ability to select between internal
and external RMII reference clock. By default, reference clock
needs to be provided via REFCLKI_3 pin. If required, device can be
setup to provide RMII clock internally so that REFCLKI_3 pin can be
left unconnected.
Add a new "microchip,rmii-clk-internal" property which will set
RMII clock reference to internal. If property is not set, reference
clock needs to be provided externally.

While at it, move the ksz8795_cpu_interface_select() to
ksz8_config_cpu_port() to get a cleaner call path for cpu port.

Signed-off-by: Ante Knezic <ante.knezic@helmholz.de>
---
 drivers/net/dsa/microchip/ksz8795.c     | 56 +++++++++++++++++++++++++++++----
 drivers/net/dsa/microchip/ksz8795_reg.h |  3 ++
 2 files changed, 53 insertions(+), 6 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz8795.c b/drivers/net/dsa/microchip/ksz8795.c
index 4bf4d67557dc..a749a4a970ec 100644
--- a/drivers/net/dsa/microchip/ksz8795.c
+++ b/drivers/net/dsa/microchip/ksz8795.c
@@ -1358,6 +1358,9 @@ static void ksz8795_cpu_interface_select(struct ksz_device *dev, int port)
 {
 	struct ksz_port *p = &dev->ports[port];
 
+	if (!ksz_is_ksz87xx(dev))
+		return;
+
 	if (!p->interface && dev->compat_interface) {
 		dev_warn(dev->dev,
 			 "Using legacy switch \"phy-mode\" property, because it is missing on port %d node. "
@@ -1391,18 +1394,55 @@ void ksz8_port_setup(struct ksz_device *dev, int port, bool cpu_port)
 	/* enable 802.1p priority */
 	ksz_port_cfg(dev, port, P_PRIO_CTRL, PORT_802_1P_ENABLE, true);
 
-	if (cpu_port) {
-		if (!ksz_is_ksz88x3(dev))
-			ksz8795_cpu_interface_select(dev, port);
-
+	if (cpu_port)
 		member = dsa_user_ports(ds);
-	} else {
+	else
 		member = BIT(dsa_upstream_port(ds, port));
-	}
 
 	ksz8_cfg_port_member(dev, port, member);
 }
 
+static int ksz88x3_config_rmii_clk(struct ksz_device *dev, int cpu_port)
+{
+	struct device_node *ports, *port, *cpu_node;
+	bool rmii_clk_internal;
+
+	if (!ksz_is_ksz88x3(dev))
+		return 0;
+
+	cpu_node = NULL;
+
+	ports = of_get_child_by_name(dev->dev->of_node, "ports");
+	if (!ports)
+		ports = of_get_child_by_name(dev->dev->of_node,
+					     "ethernet-ports");
+	if (!ports)
+		return -ENODEV;
+
+	for_each_available_child_of_node(ports, port) {
+		u32 index;
+
+		if (of_property_read_u32(port, "reg", &index) < 0)
+			return -ENODEV;
+
+		if (index == cpu_port) {
+			cpu_node = port;
+			break;
+		}
+	}
+
+	if (!cpu_node)
+		return -ENODEV;
+
+	rmii_clk_internal = of_property_read_bool(cpu_node,
+						  "microchip,rmii-clk-internal");
+
+	ksz_cfg(dev, KSZ88X3_REG_FVID_AND_HOST_MODE,
+		KSZ88X3_PORT3_RMII_CLK_INTERNAL, rmii_clk_internal);
+
+	return 0;
+}
+
 void ksz8_config_cpu_port(struct dsa_switch *ds)
 {
 	struct ksz_device *dev = ds->priv;
@@ -1419,6 +1459,10 @@ void ksz8_config_cpu_port(struct dsa_switch *ds)
 
 	ksz8_port_setup(dev, dev->cpu_port, true);
 
+	ksz8795_cpu_interface_select(dev, dev->cpu_port);
+	if (ksz88x3_config_rmii_clk(dev, dev->cpu_port))
+		dev_err(dev->dev, "Failed to set rmii reference clock source mode");
+
 	for (i = 0; i < dev->phy_port_cnt; i++) {
 		ksz_port_stp_state_set(ds, i, BR_STATE_DISABLED);
 	}
diff --git a/drivers/net/dsa/microchip/ksz8795_reg.h b/drivers/net/dsa/microchip/ksz8795_reg.h
index 3c9dae53e4d8..beca974e0171 100644
--- a/drivers/net/dsa/microchip/ksz8795_reg.h
+++ b/drivers/net/dsa/microchip/ksz8795_reg.h
@@ -22,6 +22,9 @@
 #define KSZ8863_GLOBAL_SOFTWARE_RESET	BIT(4)
 #define KSZ8863_PCS_RESET		BIT(0)
 
+#define KSZ88X3_REG_FVID_AND_HOST_MODE  0xC6
+#define KSZ88X3_PORT3_RMII_CLK_INTERNAL BIT(3)
+
 #define REG_SW_CTRL_0			0x02
 
 #define SW_NEW_BACKOFF			BIT(7)
-- 
2.11.0

Re: [PATCH net-next v5 2/2] net: dsa: microchip: add property to select internal RMII reference clock

[Vladimir Oltean]

On Fri, Nov 24, 2023 at 05:01:48PM +0100, Ante Knezic wrote:
> +static int ksz88x3_config_rmii_clk(struct ksz_device *dev, int cpu_port)
> +{
> +	struct device_node *ports, *port, *cpu_node;
> +	bool rmii_clk_internal;
> +
> +	if (!ksz_is_ksz88x3(dev))
> +		return 0;
> +
> +	cpu_node = NULL;
> +
> +	ports = of_get_child_by_name(dev->dev->of_node, "ports");
> +	if (!ports)
> +		ports = of_get_child_by_name(dev->dev->of_node,
> +					     "ethernet-ports");
> +	if (!ports)
> +		return -ENODEV;
> +
> +	for_each_available_child_of_node(ports, port) {
> +		u32 index;
> +
> +		if (of_property_read_u32(port, "reg", &index) < 0)
> +			return -ENODEV;
> +
> +		if (index == cpu_port) {
> +			cpu_node = port;
> +			break;
> +		}
> +	}
> +
> +	if (!cpu_node)
> +		return -ENODEV;

Too much code. Assuming you have struct dsa_port *cpu_dp, you can access
cpu_dp->dn instead of re-parsing the device tree.

> +
> +	rmii_clk_internal = of_property_read_bool(cpu_node,
> +						  "microchip,rmii-clk-internal");
> +
> +	ksz_cfg(dev, KSZ88X3_REG_FVID_AND_HOST_MODE,
> +		KSZ88X3_PORT3_RMII_CLK_INTERNAL, rmii_clk_internal);
> +
> +	return 0;
> +}

Please wait for 24 hours before reposting, maybe you get more feedback.