openwrt/target/linux/ramips/patches-5.15/005-v6.5-08-mips-ralink-get-cpu-rate-from-new-driver-code.patch

From ad38c17b0c26ae2108b50ac1eb0281a2e1ce08e9 Mon Sep 17 00:00:00 2001
From: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Date: Mon, 19 Jun 2023 06:09:40 +0200
Subject: [PATCH 8/9] mips: ralink: get cpu rate from new driver code

At very early stage on boot, there is a need to set 'mips_hpt_frequency'.
This timer frequency is a half of the CPU frequency. To get clocks properly
set we need to call to 'of_clk_init()' and properly get cpu clock frequency
afterwards. Depending on the SoC, CPU clock index and compatible differs, so
use them to get the proper clock frm the clock provider. Hence, adapt code
to be aligned with new clock driver.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
---
 arch/mips/ralink/clk.c | 61 ++++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 52 insertions(+), 9 deletions(-)

--- a/arch/mips/ralink/clk.c
+++ b/arch/mips/ralink/clk.c
@@ -11,29 +11,72 @@
 #include <linux/clkdev.h>
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
+#include <asm/mach-ralink/ralink_regs.h>
 
 #include <asm/time.h>
 
 #include "common.h"
 
-void ralink_clk_add(const char *dev, unsigned long rate)
+static const char *clk_cpu(int *idx)
 {
-	struct clk *clk = clk_register_fixed_rate(NULL, dev, NULL, 0, rate);
-
-	if (!clk)
-		panic("failed to add clock");
-
-	clkdev_create(clk, NULL, "%s", dev);
+	switch (ralink_soc) {
+	case RT2880_SOC:
+		*idx = 0;
+		return "ralink,rt2880-sysc";
+	case RT3883_SOC:
+		*idx = 0;
+		return "ralink,rt3883-sysc";
+	case RT305X_SOC_RT3050:
+		*idx = 0;
+		return "ralink,rt3050-sysc";
+	case RT305X_SOC_RT3052:
+		*idx = 0;
+		return "ralink,rt3052-sysc";
+	case RT305X_SOC_RT3350:
+		*idx = 1;
+		return "ralink,rt3350-sysc";
+	case RT305X_SOC_RT3352:
+		*idx = 1;
+		return "ralink,rt3352-sysc";
+	case RT305X_SOC_RT5350:
+		*idx = 1;
+		return "ralink,rt5350-sysc";
+	case MT762X_SOC_MT7620A:
+		*idx = 2;
+		return "ralink,mt7620-sysc";
+	case MT762X_SOC_MT7620N:
+		*idx = 2;
+		return "ralink,mt7620-sysc";
+	case MT762X_SOC_MT7628AN:
+		*idx = 1;
+		return "ralink,mt7628-sysc";
+	case MT762X_SOC_MT7688:
+		*idx = 1;
+		return "ralink,mt7688-sysc";
+	default:
+		*idx = -1;
+		return "invalid";
+	}
 }
 
 void __init plat_time_init(void)
 {
+	struct of_phandle_args clkspec;
+	const char *compatible;
 	struct clk *clk;
+	int cpu_clk_idx;
 
 	ralink_of_remap();
 
-	ralink_clk_init();
-	clk = clk_get_sys("cpu", NULL);
+	compatible = clk_cpu(&cpu_clk_idx);
+	if (cpu_clk_idx == -1)
+		panic("unable to get CPU clock index");
+
+	of_clk_init(NULL);
+	clkspec.np = of_find_compatible_node(NULL, NULL, compatible);
+	clkspec.args_count = 1;
+	clkspec.args[0] = cpu_clk_idx;
+	clk = of_clk_get_from_provider(&clkspec);
 	if (IS_ERR(clk))
 		panic("unable to get CPU clock, err=%ld", PTR_ERR(clk));
 	pr_info("CPU Clock: %ldMHz\n", clk_get_rate(clk) / 1000000);