From f849bcb746abeaafa63b4f02f1d8bb22703fc645 Mon Sep 17 00:00:00 2001
From: Lorenzo Bianconi <lorenzo@kernel.org>
Date: Tue, 3 Sep 2024 23:39:48 +0200
Subject: [PATCH 3/6] clk: en7523: introduce chip_scu regmap

Introduce chip_scu regmap pointer since EN7581 SoC will access chip-scu
memory area via a syscon node. Remove first memory region mapping
for EN7581 SoC. This patch does not introduce any backward incompatibility
since the dts for EN7581 SoC is not upstream yet.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 drivers/clk/clk-en7523.c | 81 ++++++++++++++++++++++++++++++----------
 1 file changed, 61 insertions(+), 20 deletions(-)

--- a/drivers/clk/clk-en7523.c
+++ b/drivers/clk/clk-en7523.c
@@ -3,8 +3,10 @@
 #include <linux/delay.h>
 #include <linux/clk-provider.h>
 #include <linux/io.h>
+#include <linux/mfd/syscon.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
+#include <linux/regmap.h>
 #include <linux/reset-controller.h>
 #include <dt-bindings/clock/en7523-clk.h>
 #include <dt-bindings/reset/airoha,en7581-reset.h>
@@ -247,15 +249,11 @@ static const u16 en7581_rst_map[] = {
 	[EN7581_XPON_MAC_RST]		= RST_NR_PER_BANK + 31,
 };
 
-static unsigned int en7523_get_base_rate(void __iomem *base, unsigned int i)
+static u32 en7523_get_base_rate(const struct en_clk_desc *desc, u32 val)
 {
-	const struct en_clk_desc *desc = &en7523_base_clks[i];
-	u32 val;
-
 	if (!desc->base_bits)
 		return desc->base_value;
 
-	val = readl(base + desc->base_reg);
 	val >>= desc->base_shift;
 	val &= (1 << desc->base_bits) - 1;
 
@@ -265,16 +263,11 @@ static unsigned int en7523_get_base_rate
 	return desc->base_values[val];
 }
 
-static u32 en7523_get_div(void __iomem *base, int i)
+static u32 en7523_get_div(const struct en_clk_desc *desc, u32 val)
 {
-	const struct en_clk_desc *desc = &en7523_base_clks[i];
-	u32 reg, val;
-
 	if (!desc->div_bits)
 		return 1;
 
-	reg = desc->div_reg ? desc->div_reg : desc->base_reg;
-	val = readl(base + reg);
 	val >>= desc->div_shift;
 	val &= (1 << desc->div_bits) - 1;
 
@@ -416,9 +409,12 @@ static void en7523_register_clocks(struc
 
 	for (i = 0; i < ARRAY_SIZE(en7523_base_clks); i++) {
 		const struct en_clk_desc *desc = &en7523_base_clks[i];
+		u32 reg = desc->div_reg ? desc->div_reg : desc->base_reg;
+		u32 val = readl(base + desc->base_reg);
 
-		rate = en7523_get_base_rate(base, i);
-		rate /= en7523_get_div(base, i);
+		rate = en7523_get_base_rate(desc, val);
+		val = readl(base + reg);
+		rate /= en7523_get_div(desc, val);
 
 		hw = clk_hw_register_fixed_rate(dev, desc->name, NULL, 0, rate);
 		if (IS_ERR(hw)) {
@@ -454,21 +450,66 @@ static int en7523_clk_hw_init(struct pla
 	return 0;
 }
 
+static void en7581_register_clocks(struct device *dev, struct clk_hw_onecell_data *clk_data,
+				   struct regmap *map, void __iomem *base)
+{
+	struct clk_hw *hw;
+	u32 rate;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(en7523_base_clks); i++) {
+		const struct en_clk_desc *desc = &en7523_base_clks[i];
+		u32 val, reg = desc->div_reg ? desc->div_reg : desc->base_reg;
+		int err;
+
+		err = regmap_read(map, desc->base_reg, &val);
+		if (err) {
+			pr_err("Failed reading fixed clk rate %s: %d\n",
+			       desc->name, err);
+			continue;
+		}
+		rate = en7523_get_base_rate(desc, val);
+
+		err = regmap_read(map, reg, &val);
+		if (err) {
+			pr_err("Failed reading fixed clk div %s: %d\n",
+			       desc->name, err);
+			continue;
+		}
+		rate /= en7523_get_div(desc, val);
+
+		hw = clk_hw_register_fixed_rate(dev, desc->name, NULL, 0, rate);
+		if (IS_ERR(hw)) {
+			pr_err("Failed to register clk %s: %ld\n",
+			       desc->name, PTR_ERR(hw));
+			continue;
+		}
+
+		clk_data->hws[desc->id] = hw;
+	}
+
+	hw = en7523_register_pcie_clk(dev, base);
+	clk_data->hws[EN7523_CLK_PCIE] = hw;
+
+	clk_data->num = EN7523_NUM_CLOCKS;
+}
+
 static int en7581_clk_hw_init(struct platform_device *pdev,
 			      struct clk_hw_onecell_data *clk_data)
 {
-	void __iomem *base, *np_base;
+	void __iomem *np_base;
+	struct regmap *map;
 	u32 val;
 
-	base = devm_platform_ioremap_resource(pdev, 0);
-	if (IS_ERR(base))
-		return PTR_ERR(base);
+	map = syscon_regmap_lookup_by_compatible("airoha,en7581-chip-scu");
+	if (IS_ERR(map))
+		return PTR_ERR(map);
 
-	np_base = devm_platform_ioremap_resource(pdev, 1);
+	np_base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(np_base))
 		return PTR_ERR(np_base);
 
-	en7523_register_clocks(&pdev->dev, clk_data, base, np_base);
+	en7581_register_clocks(&pdev->dev, clk_data, map, np_base);
 
 	val = readl(np_base + REG_NP_SCU_SSTR);
 	val &= ~(REG_PCIE_XSI0_SEL_MASK | REG_PCIE_XSI1_SEL_MASK);
@@ -545,7 +586,7 @@ static int en7523_reset_register(struct
 	if (!soc_data->reset.idx_map_nr)
 		return 0;
 
-	base = devm_platform_ioremap_resource(pdev, 2);
+	base = devm_platform_ioremap_resource(pdev, 1);
 	if (IS_ERR(base))
 		return PTR_ERR(base);