From b747f8631c2400063d0b8c44ad89f96cf046eb42 Mon Sep 17 00:00:00 2001
From: Bjarki Arge Andreasen <bjarki.andreasen@nordicsemi.no>
Date: Wed, 27 Nov 2024 21:51:13 +0100
Subject: [PATCH] [nrf fromlist] soc: nordic: nrf54h20: restrict global hsfll
 freq

Introduce feature which restricts the minimum global hsfll
frequency. This feature is selected by default to preserve the
behavior of the global hsfll before the clock control driver for
it was introduced, which configured it as a fixed clock at 320MHz.

Upstream PR #: 81735

Signed-off-by: Bjarki Arge Andreasen <bjarki.andreasen@nordicsemi.no>
---
 soc/nordic/nrf54h/CMakeLists.txt |  1 +
 soc/nordic/nrf54h/Kconfig        | 33 ++++++++++++++++
 soc/nordic/nrf54h/global_hsfll.c | 64 ++++++++++++++++++++++++++++++++
 3 files changed, 98 insertions(+)
 create mode 100644 soc/nordic/nrf54h/global_hsfll.c

diff --git a/soc/nordic/nrf54h/CMakeLists.txt b/soc/nordic/nrf54h/CMakeLists.txt
index 10c59b04583..a630a85fe79 100644
--- a/soc/nordic/nrf54h/CMakeLists.txt
+++ b/soc/nordic/nrf54h/CMakeLists.txt
@@ -9,6 +9,7 @@ if(CONFIG_ARM)
 endif()
 
 zephyr_library_sources_ifdef(CONFIG_PM_S2RAM pm_s2ram.c)
+zephyr_library_sources_ifdef(CONFIG_SOC_NRF54H20_GLOBAL_HSFLL_RESTRICT_MIN_FREQ global_hsfll.c)
 
 zephyr_include_directories(.)
 
diff --git a/soc/nordic/nrf54h/Kconfig b/soc/nordic/nrf54h/Kconfig
index 888c483e591..74bd21dd02e 100644
--- a/soc/nordic/nrf54h/Kconfig
+++ b/soc/nordic/nrf54h/Kconfig
@@ -73,3 +73,36 @@ config SOC_NRF54H20_NO_MRAM_LATENCY
 	imply NRFS
 	imply NRFS_MRAM_SERVICE_ENABLED
 	default y if SOC_NRF54H20_CPUAPP
+
+config SOC_NRF54H20_GLOBAL_HSFLL_RESTRICT_MIN_FREQ
+	bool "Restrict minimum global HSFLL clock frequency"
+	select NRFS
+	select NRFS_GDFS_SERVICE_ENABLED
+	select CLOCK_CONTROL
+	default y if SOC_NRF54H20_CPUAPP
+
+if SOC_NRF54H20_GLOBAL_HSFLL_RESTRICT_MIN_FREQ
+
+choice SOC_NRF54H20_GLOBAL_HSFLL_MIN_FREQ_CHOICE
+	prompt "Minimum global HSFLL clock frequency in MHz"
+	default SOC_NRF54H20_GLOBAL_HSFLL_MIN_FREQ_320_MHZ
+
+config SOC_NRF54H20_GLOBAL_HSFLL_MIN_FREQ_64_MHZ
+	bool "Restrict minimum global HSFLL clock frequency to 64MHz"
+
+config SOC_NRF54H20_GLOBAL_HSFLL_MIN_FREQ_128_MHZ
+	bool "Restrict minimum global HSFLL clock frequency to 128MHz"
+
+config SOC_NRF54H20_GLOBAL_HSFLL_MIN_FREQ_256_MHZ
+	bool "Restrict minimum global HSFLL clock frequency to 256MHz"
+
+config SOC_NRF54H20_GLOBAL_HSFLL_MIN_FREQ_320_MHZ
+	bool "Restrict minimum global HSFLL clock frequency to 320MHz"
+
+endchoice
+
+config SOC_NRF54H20_GLOBAL_HSFLL_TIMEOUT_MS
+	int "Global HSFLL clock frequency timeout in milliseconds"
+	default 10000
+
+endif # SOC_NRF54H20_RESTRICT_GLOBAL_HSFLL_FREQ
diff --git a/soc/nordic/nrf54h/global_hsfll.c b/soc/nordic/nrf54h/global_hsfll.c
new file mode 100644
index 00000000000..ae155a7df4c
--- /dev/null
+++ b/soc/nordic/nrf54h/global_hsfll.c
@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/drivers/clock_control/nrf_clock_control.h>
+#include <zephyr/kernel.h>
+#include <zephyr/logging/log.h>
+
+LOG_MODULE_DECLARE(soc, CONFIG_SOC_LOG_LEVEL);
+
+#if CONFIG_SOC_NRF54H20_GLOBAL_HSFLL_MIN_FREQ_64_MHZ
+#define GLOBAL_HSFLL_MIN_FREQ_HZ 64000000
+#elif CONFIG_SOC_NRF54H20_GLOBAL_HSFLL_MIN_FREQ_128_MHZ
+#define GLOBAL_HSFLL_MIN_FREQ_HZ 128000000
+#elif CONFIG_SOC_NRF54H20_GLOBAL_HSFLL_MIN_FREQ_256_MHZ
+#define GLOBAL_HSFLL_MIN_FREQ_HZ 256000000
+#else
+#define GLOBAL_HSFLL_MIN_FREQ_HZ 320000000
+#endif
+
+#define GLOBAL_HSFLL_REQUEST_TIMEOUT_US \
+	(CONFIG_SOC_NRF54H20_GLOBAL_HSFLL_TIMEOUT_MS * USEC_PER_SEC)
+
+static struct onoff_client cli;
+static const struct device *global_hsfll = DEVICE_DT_GET(DT_NODELABEL(hsfll120));
+static const struct nrf_clock_spec spec = {
+	.frequency = GLOBAL_HSFLL_MIN_FREQ_HZ,
+};
+
+static int nordicsemi_nrf54h_global_hsfll_init(void)
+{
+	int ret;
+	int res;
+	bool completed;
+
+	sys_notify_init_spinwait(&cli.notify);
+
+	ret = nrf_clock_control_request(global_hsfll, &spec, &cli);
+	if (ret) {
+		return ret;
+	}
+
+	res = -EIO;
+	completed = WAIT_FOR(sys_notify_fetch_result(&cli.notify, &res) == 0,
+			     GLOBAL_HSFLL_REQUEST_TIMEOUT_US,
+			     k_msleep(1));
+
+	if (!completed) {
+		LOG_ERR("%s request timed out", "Restrict global HSFLL");
+		return -EIO;
+	}
+
+	if (res) {
+		LOG_ERR("%s request failed: (res=%i)", "Restrict global HSFLL", res);
+		return res;
+	}
+
+	LOG_INF("%s to %uHz", "Restrict global HSFLL", GLOBAL_HSFLL_MIN_FREQ_HZ);
+	return 0;
+}
+
+SYS_INIT(nordicsemi_nrf54h_global_hsfll_init, POST_KERNEL, 99);