|
@@ -0,0 +1,137 @@
|
|
|
|
+/*
|
|
|
|
+ * Copyright 2008 Analog Devices Inc.
|
|
|
|
+ *
|
|
|
|
+ * Licensed under the GPL-2 or later.
|
|
|
|
+ */
|
|
|
|
+
|
|
|
|
+#include <linux/cdev.h>
|
|
|
|
+#include <linux/device.h>
|
|
|
|
+#include <linux/errno.h>
|
|
|
|
+#include <linux/fs.h>
|
|
|
|
+#include <linux/kernel.h>
|
|
|
|
+#include <linux/module.h>
|
|
|
|
+#include <linux/platform_device.h>
|
|
|
|
+#include <linux/types.h>
|
|
|
|
+#include <linux/cpufreq.h>
|
|
|
|
+
|
|
|
|
+#include <asm/delay.h>
|
|
|
|
+#include <asm/dpmc.h>
|
|
|
|
+
|
|
|
|
+#define DRIVER_NAME "bfin dpmc"
|
|
|
|
+
|
|
|
|
+#define dprintk(msg...) \
|
|
|
|
+ cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, DRIVER_NAME, msg)
|
|
|
|
+
|
|
|
|
+struct bfin_dpmc_platform_data *pdata;
|
|
|
|
+
|
|
|
|
+/**
|
|
|
|
+ * bfin_set_vlev - Update VLEV field in VR_CTL Reg.
|
|
|
|
+ * Avoid BYPASS sequence
|
|
|
|
+ */
|
|
|
|
+static void bfin_set_vlev(unsigned int vlev)
|
|
|
|
+{
|
|
|
|
+ unsigned pll_lcnt;
|
|
|
|
+
|
|
|
|
+ pll_lcnt = bfin_read_PLL_LOCKCNT();
|
|
|
|
+
|
|
|
|
+ bfin_write_PLL_LOCKCNT(1);
|
|
|
|
+ bfin_write_VR_CTL((bfin_read_VR_CTL() & ~VLEV) | vlev);
|
|
|
|
+ bfin_write_PLL_LOCKCNT(pll_lcnt);
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+/**
|
|
|
|
+ * bfin_get_vlev - Get CPU specific VLEV from platform device data
|
|
|
|
+ */
|
|
|
|
+static unsigned int bfin_get_vlev(unsigned int freq)
|
|
|
|
+{
|
|
|
|
+ int i;
|
|
|
|
+
|
|
|
|
+ if (!pdata)
|
|
|
|
+ goto err_out;
|
|
|
|
+
|
|
|
|
+ freq >>= 16;
|
|
|
|
+
|
|
|
|
+ for (i = 0; i < pdata->tabsize; i++)
|
|
|
|
+ if (freq <= (pdata->tuple_tab[i] & 0xFFFF))
|
|
|
|
+ return pdata->tuple_tab[i] >> 16;
|
|
|
|
+
|
|
|
|
+err_out:
|
|
|
|
+ printk(KERN_WARNING "DPMC: No suitable CCLK VDDINT voltage pair found\n");
|
|
|
|
+ return VLEV_120;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+#ifdef CONFIG_CPU_FREQ
|
|
|
|
+static int
|
|
|
|
+vreg_cpufreq_notifier(struct notifier_block *nb, unsigned long val, void *data)
|
|
|
|
+{
|
|
|
|
+ struct cpufreq_freqs *freq = data;
|
|
|
|
+
|
|
|
|
+ if (val == CPUFREQ_PRECHANGE && freq->old < freq->new) {
|
|
|
|
+ bfin_set_vlev(bfin_get_vlev(freq->new));
|
|
|
|
+ udelay(pdata->vr_settling_time); /* Wait until Volatge settled */
|
|
|
|
+
|
|
|
|
+ } else if (val == CPUFREQ_POSTCHANGE && freq->old > freq->new)
|
|
|
|
+ bfin_set_vlev(bfin_get_vlev(freq->new));
|
|
|
|
+
|
|
|
|
+ return 0;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+static struct notifier_block vreg_cpufreq_notifier_block = {
|
|
|
|
+ .notifier_call = vreg_cpufreq_notifier
|
|
|
|
+};
|
|
|
|
+#endif /* CONFIG_CPU_FREQ */
|
|
|
|
+
|
|
|
|
+/**
|
|
|
|
+ * bfin_dpmc_probe -
|
|
|
|
+ *
|
|
|
|
+ */
|
|
|
|
+static int __devinit bfin_dpmc_probe(struct platform_device *pdev)
|
|
|
|
+{
|
|
|
|
+ if (pdev->dev.platform_data)
|
|
|
|
+ pdata = pdev->dev.platform_data;
|
|
|
|
+ else
|
|
|
|
+ return -EINVAL;
|
|
|
|
+
|
|
|
|
+ return cpufreq_register_notifier(&vreg_cpufreq_notifier_block,
|
|
|
|
+ CPUFREQ_TRANSITION_NOTIFIER);
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+/**
|
|
|
|
+ * bfin_dpmc_remove -
|
|
|
|
+ */
|
|
|
|
+static int __devexit bfin_dpmc_remove(struct platform_device *pdev)
|
|
|
|
+{
|
|
|
|
+ pdata = NULL;
|
|
|
|
+ return cpufreq_unregister_notifier(&vreg_cpufreq_notifier_block,
|
|
|
|
+ CPUFREQ_TRANSITION_NOTIFIER);
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+struct platform_driver bfin_dpmc_device_driver = {
|
|
|
|
+ .probe = bfin_dpmc_probe,
|
|
|
|
+ .remove = __devexit_p(bfin_dpmc_remove),
|
|
|
|
+ .driver = {
|
|
|
|
+ .name = DRIVER_NAME,
|
|
|
|
+ }
|
|
|
|
+};
|
|
|
|
+
|
|
|
|
+/**
|
|
|
|
+ * bfin_dpmc_init - Init driver
|
|
|
|
+ */
|
|
|
|
+static int __init bfin_dpmc_init(void)
|
|
|
|
+{
|
|
|
|
+ return platform_driver_register(&bfin_dpmc_device_driver);
|
|
|
|
+}
|
|
|
|
+module_init(bfin_dpmc_init);
|
|
|
|
+
|
|
|
|
+/**
|
|
|
|
+ * bfin_dpmc_exit - break down driver
|
|
|
|
+ */
|
|
|
|
+static void __exit bfin_dpmc_exit(void)
|
|
|
|
+{
|
|
|
|
+ platform_driver_unregister(&bfin_dpmc_device_driver);
|
|
|
|
+}
|
|
|
|
+module_exit(bfin_dpmc_exit);
|
|
|
|
+
|
|
|
|
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
|
|
|
|
+MODULE_DESCRIPTION("cpu power management driver for Blackfin");
|
|
|
|
+MODULE_LICENSE("GPL");
|