/*
 * test module to check whether the TSC-based delay routine continues
 * to work properly after cpufreq transitions. Needs ACPI to work
 * properly.
 *
 * Based partly on the Power Management Timer (PMTMR) code to be found
 * in arch/i386/kernel/timers/timer_pm.c on recent 2.6. kernels, especially
 * code written by John Stultz. The read_pmtmr function was copied verbatim
 * from that file.
 *
 * (C) 2004 Dominik Brodowski
 *
 * To use:
 * 1.) pass clock=tsc to the kernel on your bootloader
 * 2.) modprobe this module (it'll fail)
 * 3.) change CPU frequency
 * 4.) modprobe this module again
 * 5.) if the third value, "diff_pmtmr", changes between 2. and 4., the
 *     TSC-based delay routine on the Linux kernel does not correctly
 *     handle the cpufreq transition. Please report this to
 *     linux-pm@vger.kernel.org
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/acpi.h>
#include <asm/io.h>

static int pm_tmr_ioport = 0;

/*helper function to safely read acpi pm timesource*/
static u32 read_pmtmr(void)
{
	u32 v1=0,v2=0,v3=0;
	/* It has been reported that because of various broken
	 * chipsets (ICH4, PIIX4 and PIIX4E) where the ACPI PM time
	 * source is not latched, so you must read it multiple
	 * times to insure a safe value is read.
	 */
	do {
		v1 = inl(pm_tmr_ioport);
		v2 = inl(pm_tmr_ioport);
		v3 = inl(pm_tmr_ioport);
	} while ((v1 > v2 && v1 < v3) || (v2 > v3 && v2 < v1)
		 || (v3 > v1 && v3 < v2));

	/* mask the output to 24 bits */
	return (v2 & 0xFFFFFF);
}

static int __init cpufreq_test_tsc(void)
{
	u32 now, then, diff;
	u64 now_tsc, then_tsc, diff_tsc;
	int i;

	/* the following code snipped is copied from arch/x86/kernel/acpi/boot.c
	   of Linux v2.6.25. */

	/* detect the location of the ACPI PM Timer */
	if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID) {
		/* FADT rev. 2 */
		if (acpi_gbl_FADT.xpm_timer_block.space_id !=
		    ACPI_ADR_SPACE_SYSTEM_IO)
			return 0;

		pm_tmr_ioport = acpi_gbl_FADT.xpm_timer_block.address;
		/*
		 * "X" fields are optional extensions to the original V1.0
		 * fields, so we must selectively expand V1.0 fields if the
		 * corresponding X field is zero.
	 	 */
		if (!pm_tmr_ioport)
			pm_tmr_ioport = acpi_gbl_FADT.pm_timer_block;
	} else {
		/* FADT rev. 1 */
		pm_tmr_ioport = acpi_gbl_FADT.pm_timer_block;
	}

	printk(KERN_DEBUG "start--> \n");
	then = read_pmtmr();
	then_tsc = rdtsc();
	for (i=0;i<20;i++) {
		mdelay(100);
		now = read_pmtmr();
		now_tsc = rdtsc();
		diff = (now - then) & 0xFFFFFF;
		diff_tsc = now_tsc - then_tsc;
		printk(KERN_DEBUG "t1: %08u t2: %08u diff_pmtmr: %08u diff_tsc: %016llu\n", then, now, diff, diff_tsc);
		then = now;
		then_tsc = now_tsc;
	}
	printk(KERN_DEBUG "<-- end \n");
	return -ENODEV;
}

static void __exit cpufreq_none(void)
{
	return;
}

module_init(cpufreq_test_tsc)
module_exit(cpufreq_none)


MODULE_AUTHOR("Dominik Brodowski");
MODULE_DESCRIPTION("Verify the TSC cpufreq notifier working correctly -- needs ACPI-enabled system");
MODULE_LICENSE ("GPL");
93b9367dab057b0f80da46a0fdb'>sound</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/i2c?h=nds-private-remove&amp;id=da5df6205b9c493b9367dab057b0f80da46a0fdb'>i2c</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/i2c/other?h=nds-private-remove&amp;id=da5df6205b9c493b9367dab057b0f80da46a0fdb'>other</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/i2c/other/ak4xxx-adda.c?h=nds-private-remove&amp;id=da5df6205b9c493b9367dab057b0f80da46a0fdb'>ak4xxx-adda.c</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/sound/i2c/other/ak4xxx-adda.c?h=nds-private-remove&amp;id=da5df6205b9c493b9367dab057b0f80da46a0fdb&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>
n value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Thomas Gleixner &lt;tglx@linutronix.de&gt;</td><td class='right'>2017-01-10 14:01:05 +0100</td></tr>
<tr><th>committer</th><td>Thomas Gleixner &lt;tglx@linutronix.de&gt;</td><td class='right'>2017-01-16 13:20:05 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/tools/arch/parisc?h=nds-private-remove&amp;id=4205e4786d0b9fc3b4fec7b1910cf645a0468307'>4205e4786d0b9fc3b4fec7b1910cf645a0468307</a> (<a href='/cgit.cgi/linux/net-next.git/patch/tools/arch/parisc?id=4205e4786d0b9fc3b4fec7b1910cf645a0468307'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=4205e4786d0b9fc3b4fec7b1910cf645a0468307'>685ccb486409197b936c785eb9d173c3edff45a1</a> /<a href='/cgit.cgi/linux/net-next.git/tree/tools/arch/parisc?h=nds-private-remove&amp;id=4205e4786d0b9fc3b4fec7b1910cf645a0468307'>tools/arch/parisc</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/tools/arch/parisc?h=nds-private-remove&amp;id=7e164ce4e8ecd7e9a58a83750bd3ee03125df154'>7e164ce4e8ecd7e9a58a83750bd3ee03125df154</a> (<a href='/cgit.cgi/linux/net-next.git/diff/tools/arch/parisc?h=nds-private-remove&amp;id=4205e4786d0b9fc3b4fec7b1910cf645a0468307&amp;id2=7e164ce4e8ecd7e9a58a83750bd3ee03125df154'>diff</a>)</td></tr></table>
<div class='commit-subject'>cpu/hotplug: Provide dynamic range for prepare stage</div><div class='commit-msg'>Mathieu reported that the LTTNG modules are broken as of 4.10-rc1 due to
the removal of the cpu hotplug notifiers.

Usually I don't care much about out of tree modules, but LTTNG is widely
used in distros. There are two ways to solve that:

1) Reserve a hotplug state for LTTNG

2) Add a dynamic range for the prepare states.

While #1 is the simplest solution, #2 is the proper one as we can convert
in tree users, which do not care about ordering, to the dynamic range as
well.

Add a dynamic range which allows LTTNG to request states in the prepare
stage.

Reported-and-tested-by: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sebastian Sewior &lt;bigeasy@linutronix.de&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701101353010.3401@nanos
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;

</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=4205e4786d0b9fc3b4fec7b1910cf645a0468307'>Diffstat</a> (limited to 'tools/arch/parisc')</div><table summary='diffstat' class='diffstat'>