Commit ee793049 authored by Andre Przywara's avatar Andre Przywara Committed by Marc Zyngier
Browse files

clocksource/arm_arch_timer: Store physical timer IRQ number for KVM on VHE 



A host running in VHE mode gets the EL2 physical timer as its time
source (accessed using the EL1 sysreg accessors, which get re-directed
to the EL2 sysregs by VHE).

The EL1 physical timer remains unused by the host kernel, allowing us to
pass that on directly to a KVM guest and saves us from emulating this
timer for the guest on VHE systems.

Store the EL1 Physical Timer's IRQ number in
struct arch_timer_kvm_info on VHE systems to allow KVM to use it.

Acked-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: default avatarAndre Przywara <andre.przywara@arm.com>
Signed-off-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: default avatarChristoffer Dall <christoffer.dall@arm.com>
parent 49a57857

drivers/clocksource/arm_arch_timer.c

+9 −2
Original line number Diff line number Diff line
@@ -1206,6 +1206,13 @@ static enum arch_timer_ppi_nr __init arch_timer_select_ppi(void) 
	return ARCH_TIMER_PHYS_SECURE_PPI;

}



static void __init arch_timer_populate_kvm_info(void)

{

	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[ARCH_TIMER_VIRT_PPI];

	if (is_kernel_in_hyp_mode())

		arch_timer_kvm_info.physical_irq = arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI];

}



static int __init arch_timer_of_init(struct device_node *np)

{

	int i, ret;
@@ -1220,7 +1227,7 @@ static int __init arch_timer_of_init(struct device_node *np) 
	for (i = ARCH_TIMER_PHYS_SECURE_PPI; i < ARCH_TIMER_MAX_TIMER_PPI; i++)

		arch_timer_ppi[i] = irq_of_parse_and_map(np, i);



	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[ARCH_TIMER_VIRT_PPI];

	arch_timer_populate_kvm_info();



	rate = arch_timer_get_cntfrq();

	arch_timer_of_configure_rate(rate, np);
@@ -1550,7 +1557,7 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table) 
	arch_timer_ppi[ARCH_TIMER_HYP_PPI] =

		acpi_gtdt_map_ppi(ARCH_TIMER_HYP_PPI);



	arch_timer_kvm_info.virtual_irq = arch_timer_ppi[ARCH_TIMER_VIRT_PPI];

	arch_timer_populate_kvm_info();



	/*

	 * When probing via ACPI, we have no mechanism to override the sysreg

include/clocksource/arm_arch_timer.h

+1 −0
Original line number Diff line number Diff line
@@ -74,6 +74,7 @@ enum arch_timer_spi_nr { 
struct arch_timer_kvm_info {

	struct timecounter timecounter;

	int virtual_irq;

	int physical_irq;

};



struct arch_timer_mem_frame {

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