Commit 87e65d05 authored by Jan Kiszka's avatar Jan Kiszka Committed by Thomas Gleixner
Browse files

x86/jailhouse: Enable PMTIMER 



Jailhouse exposes the PMTIMER as only reference clock to all cells. Pick
up its address from the setup data. Allow to enable the Linux support of
it by relaxing its strict dependency on ACPI.

Signed-off-by: default avatarJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: jailhouse-dev@googlegroups.com
Link: https://lkml.kernel.org/r/6d5c3fadd801eb3fba9510e2d3db14a9c404a1a0.1511770314.git.jan.kiszka@siemens.com
parent 11c8dc41

arch/x86/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -799,6 +799,7 @@ config PARAVIRT_CLOCK 
config JAILHOUSE_GUEST

	bool "Jailhouse non-root cell support"

	depends on X86_64

	select X86_PM_TIMER

	---help---

	  This option allows to run Linux as guest in a Jailhouse non-root

	  cell. You can leave this option disabled if you only want to start

arch/x86/kernel/jailhouse.c

+4 −0
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
 *  Jan Kiszka <jan.kiszka@siemens.com>

 */



#include <linux/acpi_pmtmr.h>

#include <linux/kernel.h>

#include <asm/apic.h>

#include <asm/cpu.h>
@@ -91,6 +92,9 @@ static void __init jailhouse_init_platform(void) 


	if (setup_data.compatible_version > JAILHOUSE_SETUP_REQUIRED_VERSION)

		panic("Jailhouse: Unsupported setup data structure");



	pmtmr_ioport = setup_data.pm_timer_address;

	pr_debug("Jailhouse: PM-Timer IO Port: %#x\n", pmtmr_ioport);

}



bool jailhouse_paravirt(void)

drivers/acpi/Kconfig

+16 −16
Original line number Diff line number Diff line
@@ -361,22 +361,6 @@ config ACPI_PCI_SLOT 
	  i.e., segment/bus/device/function tuples, with physical slots in

	  the system.  If you are unsure, say N.



config X86_PM_TIMER

	bool "Power Management Timer Support" if EXPERT

	depends on X86

	default y

	help

	  The Power Management Timer is available on all ACPI-capable,

	  in most cases even if ACPI is unusable or blacklisted.



	  This timing source is not affected by power management features

	  like aggressive processor idling, throttling, frequency and/or

	  voltage scaling, unlike the commonly used Time Stamp Counter

	  (TSC) timing source.



	  You should nearly always say Y here because many modern

	  systems require this timer. 



config ACPI_CONTAINER

	bool "Container and Module Devices"

	default (ACPI_HOTPLUG_MEMORY || ACPI_HOTPLUG_CPU)
@@ -564,3 +548,19 @@ config TPS68470_PMIC_OPREGION 
	  using this, are probed.



endif	# ACPI



config X86_PM_TIMER

	bool "Power Management Timer Support" if EXPERT

	depends on X86 && (ACPI || JAILHOUSE_GUEST)

	default y

	help

	  The Power Management Timer is available on all ACPI-capable,

	  in most cases even if ACPI is unusable or blacklisted.



	  This timing source is not affected by power management features

	  like aggressive processor idling, throttling, frequency and/or

	  voltage scaling, unlike the commonly used Time Stamp Counter

	  (TSC) timing source.



	  You should nearly always say Y here because many modern

	  systems require this timer.

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