The Allwinner A20/A31 clock module controls the transmit clock source
and interface type of the GMAC ethernet controller. Model this as
a single clock for GMAC drivers to use.
Signed-off-by: Chen-Yu Tsai <wens@xxxxxxxx>
---
Documentation/devicetree/bindings/clock/sunxi.txt | 26 +++++++
drivers/clk/sunxi/clk-sunxi.c | 83 +++++++++++++++++++++++
2 files changed, 109 insertions(+)
diff --git a/Documentation/devicetree/bindings/clock/sunxi.txt b/Documentation/devicetree/bindings/clock/sunxi.txt
index 0cf679b..f43b4c0 100644
--- a/Documentation/devicetree/bindings/clock/sunxi.txt
+++ b/Documentation/devicetree/bindings/clock/sunxi.txt
@@ -37,6 +37,7 @@ Required properties:
"allwinner,sun6i-a31-apb2-gates-clk" - for the APB2 gates on A31
"allwinner,sun4i-mod0-clk" - for the module 0 family of clocks
"allwinner,sun7i-a20-out-clk" - for the external output clocks
+ "allwinner,sun7i-a20-gmac-clk" - for the GMAC clock module on A20/A31
Required properties for all clocks:
- reg : shall be the control register address for the clock.
@@ -50,6 +51,9 @@ Required properties for all clocks:
If the clock module only has one output, the name shall be the
module name.
+For "allwinner,sun7i-a20-gmac-clk", the parent clocks shall be fixed rate
+dummy clocks at 25 MHz and 125 MHz, respectively. See example.
+
Clock consumers should specify the desired clocks they use with a
"clocks" phandle cell. Consumers that are using a gated clock should
provide an additional ID in their clock property. This ID is the
@@ -96,3 +100,25 @@ mmc0_clk: clk@01c20088 {
clocks = <&osc24M>, <&pll6 1>, <&pll5 1>;
clock-output-names = "mmc0";
};
+
+mii_phy_tx_clk: clk@2 {
+ #clock-cells = <0>;
+ compatible = "fixed-clock";
+ clock-frequency = <25000000>;
+ clock-output-names = "mii_phy_tx";
+};
+
+gmac_int_tx_clk: clk@3 {
+ #clock-cells = <0>;
+ compatible = "fixed-clock";
+ clock-frequency = <125000000>;
+ clock-output-names = "gmac_int_tx";
+};
+
+gmac_clk: clk@01c20164 {
+ #clock-cells = <0>;
+ compatible = "allwinner,sun7i-a20-gmac-clk";
+ reg = <0x01c20164 0x4>;
+ clocks = <&mii_phy_tx_clk>, <&gmac_int_tx_clk>;
+ clock-output-names = "gmac";
+};
diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c
index 736fb60..0b361d2 100644
--- a/drivers/clk/sunxi/clk-sunxi.c
+++ b/drivers/clk/sunxi/clk-sunxi.c
@@ -379,6 +379,89 @@ static void sun7i_a20_get_out_factors(u32 *freq, u32 parent_rate,
/**
+ * sun7i_a20_gmac_clk_setup - Setup function for A20/A31 GMAC clock module
+ *
+ * This clock looks something like this
+ * ________________________
+ * MII TX clock from PHY >-----|___________ _________|----> to GMAC core
+ * GMAC Int. RGMII TX clk >----|___________\__/__gate---|----> to PHY
+ * Ext. 125MHz RGMII TX clk >--|__divider__/ |
+ * |________________________|
+ *
+ * The external 125 MHz reference is optional, i.e. GMAC can use its
+ * internal TX clock just fine. The A31 GMAC clock module does not have
+ * the divider controls for the external reference.
+ *
+ * To keep it simple, let the GMAC use either the MII TX clock for MII mode,
+ * and its internal TX clock for GMII and RGMII modes. The GMAC driver should
+ * select the appropriate source and gate/ungate the output to the PHY.
+ *
+ * Only the GMAC should use this clock. Altering the clock so that it doesn't
+ * match the GMAC's operation parameters will result in the GMAC not being
+ * able to send traffic out. The GMAC driver should set the clock rate and
+ * enable/disable this clock to configure the required state. The clock
+ * driver then responds by auto-reparenting the clock.
+ */
+
+#define SUN7I_A20_GMAC_GPIT 2
+#define SUN7I_A20_GMAC_MASK 0x3
+#define SUN7I_A20_GMAC_MAX_PARENTS 2
+
+static void __init sun7i_a20_gmac_clk_setup(struct device_node *node)
+{
+ struct clk *clk;
+ struct clk_mux *mux;
+ struct clk_gate *gate;
+ const char *clk_name = node->name;
+ const char *parents[SUN7I_A20_GMAC_MAX_PARENTS];
+ void *reg;
+ int i = 0;
+
+ /* allocate mux and gate clock structs */
+ mux = kzalloc(sizeof(struct clk_mux), GFP_KERNEL);
+ if (!mux)
+ return;
+ gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);
+ if (!gate) {
+ kfree(mux);
+ return;
+ }
+
+ reg = of_iomap(node, 0);
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+
+ while (i < SUN7I_A20_GMAC_MAX_PARENTS &&
+ (parents[i] = of_clk_get_parent_name(node, i)) != NULL)
+ i++;
+
+ /* set up gate and fixed rate properties */
+ gate->reg = reg;
+ gate->bit_idx = SUN7I_A20_GMAC_GPIT;
+ gate->lock = &clk_lock;
+ mux->reg = reg;
+ mux->mask = SUN7I_A20_GMAC_MASK;
+ mux->flags = CLK_MUX_INDEX_BIT;
+ mux->lock = &clk_lock;
+
+ clk = clk_register_composite(NULL, clk_name,
+ parents, i,
+ &mux->hw, &clk_mux_ops,
+ NULL, NULL,
+ &gate->hw, &clk_gate_ops,
+ 0);
+
+ if (!IS_ERR(clk)) {
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ clk_register_clkdev(clk, clk_name, NULL);
+ }
+}
+CLK_OF_DECLARE(sun7i_a20_gmac, "allwinner,sun7i-a20-gmac-clk",
+ sun7i_a20_gmac_clk_setup);
+
+
+
+/**
* sunxi_factors_clk_setup() - Setup function for factor clocks
*/
--
1.9.rc1
--
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