Hi Andre, On 03/21/2018 04:31 PM, Andre Przywara wrote:
When playing around with hardware mapped, level triggered virtual IRQs, there is the need to explicitly set the active or pending state of an interrupt at some point. To prepare the GIC for that, we introduce a set_active_state() and a set_pending_state() function to let the VGIC manipulate the state of an associated hardware IRQ. This takes care of properly setting the _IRQ_INPROGRESS bit.Signed-off-by: Andre Przywara <andre.przyw...@linaro.org> --- Changelog v2 ... v3: - rework setting _IRQ_INPROGRESS bit: - no change when changing active state - unconditional set/clear on changing pending state - drop introduction of gicv[23]_peek_irq() (only needed in the next patch now) Changelog v1 ... v2: - properly set _IRQ_INPROGRESS bit - add gicv[23]_peek_irq() (pulled in from later patch) - move wrappers functions into gic.h xen/arch/arm/gic-v2.c | 36 ++++++++++++++++++++++++++++++++++++ xen/arch/arm/gic-v3.c | 32 ++++++++++++++++++++++++++++++++ xen/include/asm-arm/gic.h | 24 ++++++++++++++++++++++++ 3 files changed, 92 insertions(+) diff --git a/xen/arch/arm/gic-v2.c b/xen/arch/arm/gic-v2.c index aa0fc6c1a1..d1f1578c05 100644 --- a/xen/arch/arm/gic-v2.c +++ b/xen/arch/arm/gic-v2.c @@ -243,6 +243,40 @@ static void gicv2_poke_irq(struct irq_desc *irqd, uint32_t offset) writel_gicd(1U << (irqd->irq % 32), offset + (irqd->irq / 32) * 4); }+static void gicv2_set_active_state(struct irq_desc *irqd, bool active)+{ + ASSERT(spin_is_locked(&irqd->lock)); + + if ( active ) + { + if ( test_bit(_IRQ_GUEST, &irqd->status) )
I don't understand why you only set/clear INPROGRESS bit for interrupt routed to guest. This will matter when releasing interrupt used by Xen (see release_irq).
Note that I don't expect this helper to be call on Xen IRQ, but I think we should make
Other than same remark on GICv3 code, the pending implementation looks good to me now.
Cheers, -- Julien Grall _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
