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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/arm/mach-s3c/mach-osiris-dvs.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm/mach-s3c/mach-osiris-dvs.c')
-rw-r--r--arch/arm/mach-s3c/mach-osiris-dvs.c178
1 files changed, 178 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c/mach-osiris-dvs.c b/arch/arm/mach-s3c/mach-osiris-dvs.c
new file mode 100644
index 000000000..2e283aeda
--- /dev/null
+++ b/arch/arm/mach-s3c/mach-osiris-dvs.c
@@ -0,0 +1,178 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (c) 2009 Simtec Electronics
+// http://armlinux.simtec.co.uk/
+// Ben Dooks <ben@simtec.co.uk>
+//
+// Simtec Osiris Dynamic Voltage Scaling support.
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/cpufreq.h>
+#include <linux/gpio.h>
+
+#include <linux/mfd/tps65010.h>
+
+#include <linux/soc/samsung/s3c-cpu-freq.h>
+#include "gpio-samsung.h"
+
+#define OSIRIS_GPIO_DVS S3C2410_GPB(5)
+
+static bool dvs_en;
+
+static void osiris_dvs_tps_setdvs(bool on)
+{
+ unsigned vregs1 = 0, vdcdc2 = 0;
+
+ if (!on) {
+ vdcdc2 = TPS_VCORE_DISCH | TPS_LP_COREOFF;
+ vregs1 = TPS_LDO1_OFF; /* turn off in low-power mode */
+ }
+
+ dvs_en = on;
+ vdcdc2 |= TPS_VCORE_1_3V | TPS_VCORE_LP_1_0V;
+ vregs1 |= TPS_LDO2_ENABLE | TPS_LDO1_ENABLE;
+
+ tps65010_config_vregs1(vregs1);
+ tps65010_config_vdcdc2(vdcdc2);
+}
+
+static bool is_dvs(struct s3c_freq *f)
+{
+ /* at the moment, we assume ARMCLK = HCLK => DVS */
+ return f->armclk == f->hclk;
+}
+
+/* keep track of current state */
+static bool cur_dvs = false;
+
+static int osiris_dvs_notify(struct notifier_block *nb,
+ unsigned long val, void *data)
+{
+ struct cpufreq_freqs *cf = data;
+ struct s3c_cpufreq_freqs *freqs = to_s3c_cpufreq(cf);
+ bool old_dvs = is_dvs(&freqs->old);
+ bool new_dvs = is_dvs(&freqs->new);
+ int ret = 0;
+
+ if (!dvs_en)
+ return 0;
+
+ printk(KERN_DEBUG "%s: old %ld,%ld new %ld,%ld\n", __func__,
+ freqs->old.armclk, freqs->old.hclk,
+ freqs->new.armclk, freqs->new.hclk);
+
+ switch (val) {
+ case CPUFREQ_PRECHANGE:
+ if ((old_dvs && !new_dvs) ||
+ (cur_dvs && !new_dvs)) {
+ pr_debug("%s: exiting dvs\n", __func__);
+ cur_dvs = false;
+ gpio_set_value(OSIRIS_GPIO_DVS, 1);
+ }
+ break;
+ case CPUFREQ_POSTCHANGE:
+ if ((!old_dvs && new_dvs) ||
+ (!cur_dvs && new_dvs)) {
+ pr_debug("entering dvs\n");
+ cur_dvs = true;
+ gpio_set_value(OSIRIS_GPIO_DVS, 0);
+ }
+ break;
+ }
+
+ return ret;
+}
+
+static struct notifier_block osiris_dvs_nb = {
+ .notifier_call = osiris_dvs_notify,
+};
+
+static int osiris_dvs_probe(struct platform_device *pdev)
+{
+ int ret;
+
+ dev_info(&pdev->dev, "initialising\n");
+
+ ret = gpio_request(OSIRIS_GPIO_DVS, "osiris-dvs");
+ if (ret) {
+ dev_err(&pdev->dev, "cannot claim gpio\n");
+ goto err_nogpio;
+ }
+
+ /* start with dvs disabled */
+ gpio_direction_output(OSIRIS_GPIO_DVS, 1);
+
+ ret = cpufreq_register_notifier(&osiris_dvs_nb,
+ CPUFREQ_TRANSITION_NOTIFIER);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register with cpufreq\n");
+ goto err_nofreq;
+ }
+
+ osiris_dvs_tps_setdvs(true);
+
+ return 0;
+
+err_nofreq:
+ gpio_free(OSIRIS_GPIO_DVS);
+
+err_nogpio:
+ return ret;
+}
+
+static int osiris_dvs_remove(struct platform_device *pdev)
+{
+ dev_info(&pdev->dev, "exiting\n");
+
+ /* disable any current dvs */
+ gpio_set_value(OSIRIS_GPIO_DVS, 1);
+ osiris_dvs_tps_setdvs(false);
+
+ cpufreq_unregister_notifier(&osiris_dvs_nb,
+ CPUFREQ_TRANSITION_NOTIFIER);
+
+ gpio_free(OSIRIS_GPIO_DVS);
+
+ return 0;
+}
+
+/* the CONFIG_PM block is so small, it isn't worth actually compiling it
+ * out if the configuration isn't set. */
+
+static int osiris_dvs_suspend(struct device *dev)
+{
+ gpio_set_value(OSIRIS_GPIO_DVS, 1);
+ osiris_dvs_tps_setdvs(false);
+ cur_dvs = false;
+
+ return 0;
+}
+
+static int osiris_dvs_resume(struct device *dev)
+{
+ osiris_dvs_tps_setdvs(true);
+ return 0;
+}
+
+static const struct dev_pm_ops osiris_dvs_pm = {
+ .suspend = osiris_dvs_suspend,
+ .resume = osiris_dvs_resume,
+};
+
+static struct platform_driver osiris_dvs_driver = {
+ .probe = osiris_dvs_probe,
+ .remove = osiris_dvs_remove,
+ .driver = {
+ .name = "osiris-dvs",
+ .pm = &osiris_dvs_pm,
+ },
+};
+
+module_platform_driver(osiris_dvs_driver);
+
+MODULE_DESCRIPTION("Simtec OSIRIS DVS support");
+MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:osiris-dvs");