clk: imx: scu: add gpr clocks support

SCU clock protocol supports a few clocks based on GPR controller
registers including mux/divider/gate.
Add a generic clock register API to support them all.
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Signed-off-by: Abel Vesa <abel.vesa@nxp.com>

drivers/clk/imx/clk-scu.c

@@ -52,6 +52,22 @@ struct clk_scu {
 	u32 rate;
 };
 
+/*
+ * struct clk_gpr_scu - Description of one SCU GPR clock
+ * @hw: the common clk_hw
+ * @rsrc_id: resource ID of this SCU clock
+ * @gpr_id: GPR ID index to control the divider
+ */
+struct clk_gpr_scu {
+	struct clk_hw hw;
+	u16 rsrc_id;
+	u8 gpr_id;
+	u8 flags;
+	bool gate_invert;
+};
+
+#define to_clk_gpr_scu(_hw) container_of(_hw, struct clk_gpr_scu, hw)
+
 /*
  * struct imx_sc_msg_req_set_clock_rate - clock set rate protocol
  * @hdr: SCU protocol header
@@ -605,3 +621,173 @@ void imx_clk_scu_unregister(void)
 		}
 	}
 }
+
+static unsigned long clk_gpr_div_scu_recalc_rate(struct clk_hw *hw,
+						 unsigned long parent_rate)
+{
+	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
+	unsigned long rate = 0;
+	u32 val;
+	int err;
+
+	err = imx_sc_misc_get_control(ccm_ipc_handle, clk->rsrc_id,
+				      clk->gpr_id, &val);
+
+	rate  = val ? parent_rate / 2 : parent_rate;
+
+	return err ? 0 : rate;
+}
+
+static long clk_gpr_div_scu_round_rate(struct clk_hw *hw, unsigned long rate,
+				   unsigned long *prate)
+{
+	if (rate < *prate)
+		rate = *prate / 2;
+	else
+		rate = *prate;
+
+	return rate;
+}
+
+static int clk_gpr_div_scu_set_rate(struct clk_hw *hw, unsigned long rate,
+				    unsigned long parent_rate)
+{
+	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
+	uint32_t val;
+	int err;
+
+	val = (rate < parent_rate) ? 1 : 0;
+	err = imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
+				      clk->gpr_id, val);
+
+	return err ? -EINVAL : 0;
+}
+
+static const struct clk_ops clk_gpr_div_scu_ops = {
+	.recalc_rate = clk_gpr_div_scu_recalc_rate,
+	.round_rate = clk_gpr_div_scu_round_rate,
+	.set_rate = clk_gpr_div_scu_set_rate,
+};
+
+static u8 clk_gpr_mux_scu_get_parent(struct clk_hw *hw)
+{
+	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
+	u32 val = 0;
+
+	imx_sc_misc_get_control(ccm_ipc_handle, clk->rsrc_id,
+				clk->gpr_id, &val);
+
+	return (u8)val;
+}
+
+static int clk_gpr_mux_scu_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
+
+	return imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
+				       clk->gpr_id, index);
+}
+
+static const struct clk_ops clk_gpr_mux_scu_ops = {
+	.get_parent = clk_gpr_mux_scu_get_parent,
+	.set_parent = clk_gpr_mux_scu_set_parent,
+};
+
+static int clk_gpr_gate_scu_prepare(struct clk_hw *hw)
+{
+	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
+
+	return imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
+				       clk->gpr_id, !clk->gate_invert);
+}
+
+static void clk_gpr_gate_scu_unprepare(struct clk_hw *hw)
+{
+	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
+	int ret;
+
+	ret = imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
+				      clk->gpr_id, clk->gate_invert);
+	if (ret)
+		pr_err("%s: clk unprepare failed %d\n", clk_hw_get_name(hw),
+		       ret);
+}
+
+static int clk_gpr_gate_scu_is_prepared(struct clk_hw *hw)
+{
+	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
+	int ret;
+	u32 val;
+
+	ret = imx_sc_misc_get_control(ccm_ipc_handle, clk->rsrc_id,
+				      clk->gpr_id, &val);
+	if (ret)
+		return ret;
+
+	return clk->gate_invert ? !val : val;
+}
+
+static const struct clk_ops clk_gpr_gate_scu_ops = {
+	.prepare = clk_gpr_gate_scu_prepare,
+	.unprepare = clk_gpr_gate_scu_unprepare,
+	.is_prepared = clk_gpr_gate_scu_is_prepared,
+};
+
+struct clk_hw *__imx_clk_gpr_scu(const char *name, const char * const *parent_name,
+				 int num_parents, u32 rsrc_id, u8 gpr_id, u8 flags,
+				 bool invert)
+{
+	struct imx_scu_clk_node *clk_node;
+	struct clk_gpr_scu *clk;
+	struct clk_hw *hw;
+	struct clk_init_data init;
+	int ret;
+
+	if (rsrc_id >= IMX_SC_R_LAST || gpr_id >= IMX_SC_C_LAST)
+		return ERR_PTR(-EINVAL);
+
+	clk_node = kzalloc(sizeof(*clk_node), GFP_KERNEL);
+	if (!clk_node)
+		return ERR_PTR(-ENOMEM);
+
+	clk = kzalloc(sizeof(*clk), GFP_KERNEL);
+	if (!clk) {
+		kfree(clk_node);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	clk->rsrc_id = rsrc_id;
+	clk->gpr_id = gpr_id;
+	clk->flags = flags;
+	clk->gate_invert = invert;
+
+	if (flags & IMX_SCU_GPR_CLK_GATE)
+		init.ops = &clk_gpr_gate_scu_ops;
+
+	if (flags & IMX_SCU_GPR_CLK_DIV)
+		init.ops = &clk_gpr_div_scu_ops;
+
+	if (flags & IMX_SCU_GPR_CLK_MUX)
+		init.ops = &clk_gpr_mux_scu_ops;
+
+	init.flags = 0;
+	init.name = name;
+	init.parent_names = parent_name;
+	init.num_parents = num_parents;
+
+	clk->hw.init = &init;
+
+	hw = &clk->hw;
+	ret = clk_hw_register(NULL, hw);
+	if (ret) {
+		kfree(clk);
+		kfree(clk_node);
+		hw = ERR_PTR(ret);
+	} else {
+		clk_node->hw = hw;
+		clk_node->clk_type = gpr_id;
+		list_add_tail(&clk_node->node, &imx_scu_clks[rsrc_id]);
+	}
+
+	return hw;
+}

drivers/clk/imx/clk-scu.h

@@ -10,6 +10,10 @@
 #include <linux/firmware/imx/sci.h>
 #include <linux/of.h>
 
+#define IMX_SCU_GPR_CLK_GATE	BIT(0)
+#define IMX_SCU_GPR_CLK_DIV	BIT(1)
+#define IMX_SCU_GPR_CLK_MUX	BIT(2)
+
 extern struct list_head imx_scu_clks[];
 extern const struct dev_pm_ops imx_clk_lpcg_scu_pm_ops;
 
@@ -31,6 +35,10 @@ struct clk_hw *__imx_clk_lpcg_scu(struct device *dev, const char *name,
 				  void __iomem *reg, u8 bit_idx, bool hw_gate);
 void imx_clk_lpcg_scu_unregister(struct clk_hw *hw);
 
+struct clk_hw *__imx_clk_gpr_scu(const char *name, const char * const *parent_name,
+				 int num_parents, u32 rsrc_id, u8 gpr_id, u8 flags,
+				 bool invert);
+
 static inline struct clk_hw *imx_clk_scu(const char *name, u32 rsrc_id,
 					 u8 clk_type)
 {
@@ -58,4 +66,25 @@ static inline struct clk_hw *imx_clk_lpcg_scu(const char *name, const char *pare
 	return __imx_clk_lpcg_scu(NULL, name, parent_name, flags, reg,
 				  bit_idx, hw_gate);
 }
+
+static inline struct clk_hw *imx_clk_gate_gpr_scu(const char *name, const char *parent_name,
+						  u32 rsrc_id, u8 gpr_id, bool invert)
+{
+	return __imx_clk_gpr_scu(name, &parent_name, 1, rsrc_id, gpr_id,
+				 IMX_SCU_GPR_CLK_GATE, invert);
+}
+
+static inline struct clk_hw *imx_clk_divider_gpr_scu(const char *name, const char *parent_name,
+						     u32 rsrc_id, u8 gpr_id)
+{
+	return __imx_clk_gpr_scu(name, &parent_name, 1, rsrc_id, gpr_id,
+				 IMX_SCU_GPR_CLK_DIV, 0);
+}
+
+static inline struct clk_hw *imx_clk_mux_gpr_scu(const char *name, const char * const *parent_names,
+						 int num_parents, u32 rsrc_id, u8 gpr_id)
+{
+	return __imx_clk_gpr_scu(name, parent_names, num_parents, rsrc_id,
+				 gpr_id, IMX_SCU_GPR_CLK_MUX, 0);
+}
 #endif