clk: stm32mp1: Add parent_data to ETHRX clock

Pass parent_data to ETHRX clock with new fw_name = "ETH_RX_CLK/ETH_REF_CLK".
By default, this change has no impact on the operation of the clock driver.
However, due to the fw_name, it permits DT to override ETHRX clock parent,
which might be needed in case the ETHRX clock are supplied by external clock
source.

Example of MCO2 supplying clock to ETH_RX_CLK via external pad-to-pad wire:
&rcc {
clocks = <&rcc CK_MCO2>;
clock-names = "ETH_RX_CLK/ETH_REF_CLK";
};

Note that while this patch permits to implement this rare usecase, the issue
with ethernet RX and TX input clock modeling on MP1 is far more complex and
requires more core plumbing.

[1] STM32MP1 Reference Manual RM0436 Rev 3, Page 574,
Figure 83. Peripheral clock distribution for Ethernet
https://www.st.com/resource/en/reference_manual/dm00327659-stm32mp157-advanced-armbased-32bit-mpus-stmicroelectronics.pdf

Signed-off-by: Marek Vasut <[e-mail]>
Cc: Alexandre Torgue <[e-mail]>
Cc: Christophe Roullier <[e-mail]>
Cc: Gabriel Fernandez <[e-mail]>
Cc: Patrice Chotard <[e-mail]>
Cc: Patrick Delaunay <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Link: https://lore.kernel.org/r/[e-mail]
Tested-by: Johann Neuhauser <[e-mail]>
Acked-by: Gabriel Fernandez <[e-mail]>
Signed-off-by: Stephen Boyd <[e-mail]>

drivers/clk/clk-stm32mp1.c

···
 	"pll4_p", "pll3_q"
 };
 
+const struct clk_parent_data ethrx_src[] = {
+	{ .name = "ethck_k", .fw_name = "ETH_RX_CLK/ETH_REF_CLK" },
+};
+
 static const char * const rng_src[] = {
 	"ck_csi", "pll4_r", "ck_lse", "ck_lsi"
 };
···
 	const char *name;
 	const char *parent_name;
 	const char * const *parent_names;
+	const struct clk_parent_data *parent_data;
 	int num_parents;
 	unsigned long flags;
 	void *cfg;
···
 clk_stm32_register_gate_ops(struct device *dev,
 			    const char *name,
 			    const char *parent_name,
+			    const struct clk_parent_data *parent_data,
 			    unsigned long flags,
 			    void __iomem *base,
 			    const struct stm32_gate_cfg *cfg,
···
 	int ret;
 
 	init.name = name;
-	init.parent_names = &parent_name;
+	if (parent_name)
+		init.parent_names = &parent_name;
+	if (parent_data)
+		init.parent_data = parent_data;
 	init.num_parents = 1;
 	init.flags = flags;
 
···
 static struct clk_hw *
 clk_stm32_register_composite(struct device *dev,
 			     const char *name, const char * const *parent_names,
+			     const struct clk_parent_data *parent_data,
 			     int num_parents, void __iomem *base,
 			     const struct stm32_composite_cfg *cfg,
 			     unsigned long flags, spinlock_t *lock)
···
 	return clk_stm32_register_gate_ops(dev,
 				    cfg->name,
 				    cfg->parent_name,
+				    cfg->parent_data,
 				    cfg->flags,
 				    base,
 				    cfg->cfg,
···
 			      const struct clock_config *cfg)
 {
 	return clk_stm32_register_composite(dev, cfg->name, cfg->parent_names,
-					    cfg->num_parents, base, cfg->cfg,
-					    cfg->flags, lock);
+					    cfg->parent_data, cfg->num_parents,
+					    base, cfg->cfg, cfg->flags, lock);
 }
 
 #define GATE(_id, _name, _parent, _flags, _offset, _bit_idx, _gate_flags)\
···
 	.func		= _clk_stm32_register_gate,\
 }
 
+#define STM32_GATE_PDATA(_id, _name, _parent, _flags, _gate)\
+{\
+	.id		= _id,\
+	.name		= _name,\
+	.parent_data	= _parent,\
+	.flags		= _flags,\
+	.cfg		= (struct stm32_gate_cfg *) {_gate},\
+	.func		= _clk_stm32_register_gate,\
+}
+
 #define _STM32_GATE(_gate_offset, _gate_bit_idx, _gate_flags, _mgate, _ops)\
 	(&(struct stm32_gate_cfg) {\
 		&(struct gate_cfg) {\
···
 
 #define MGATE_MP1(_id, _name, _parent, _flags, _mgate)\
 	STM32_GATE(_id, _name, _parent, _flags,\
+		   _STM32_MGATE(_mgate))
+
+#define MGATE_MP1_PDATA(_id, _name, _parent, _flags, _mgate)\
+	STM32_GATE_PDATA(_id, _name, _parent, _flags,\
 		   _STM32_MGATE(_mgate))
 
 #define _STM32_DIV(_div_offset, _div_shift, _div_width,\
···
 
 #define PCLK(_id, _name, _parent, _flags, _mgate)\
 	MGATE_MP1(_id, _name, _parent, _flags, _mgate)
+
+#define PCLK_PDATA(_id, _name, _parent, _flags, _mgate)\
+	MGATE_MP1_PDATA(_id, _name, _parent, _flags, _mgate)
 
 #define KCLK(_id, _name, _parents, _flags, _mgate, _mmux)\
 	     COMPOSITE(_id, _name, _parents, CLK_OPS_PARENT_ENABLE |\
···
 	PCLK(MDMA, "mdma", "ck_axi", 0, G_MDMA),
 	PCLK(GPU, "gpu", "ck_axi", 0, G_GPU),
 	PCLK(ETHTX, "ethtx", "ck_axi", 0, G_ETHTX),
-	PCLK(ETHRX, "ethrx", "ck_axi", 0, G_ETHRX),
+	PCLK_PDATA(ETHRX, "ethrx", ethrx_src, 0, G_ETHRX),
 	PCLK(ETHMAC, "ethmac", "ck_axi", 0, G_ETHMAC),
 	PCLK(FMC, "fmc", "ck_axi", CLK_IGNORE_UNUSED, G_FMC),
 	PCLK(QSPI, "qspi", "ck_axi", CLK_IGNORE_UNUSED, G_QSPI),