From: will.deacon@arm•com (Will Deacon)
To: linux-arm-kernel@lists•infradead.org
Subject: [RFC PATCH 4/9] irqchip: GIC: add support for forwarded interrupts
Date: Fri, 27 Jun 2014 14:17:48 +0100 [thread overview]
Message-ID: <20140627131748.GT26276@arm.com> (raw)
In-Reply-To: <1403688530-23273-5-git-send-email-marc.zyngier@arm.com>
Hi Marc,
On Wed, Jun 25, 2014 at 10:28:45AM +0100, Marc Zyngier wrote:
> Now that we've switched to EOImode == 1, prevent a forwarded interrupt
> from being deactivated after its priority has been dropped.
>
> Also add support for the interrupt state to be saved/restored.
>
> Signed-off-by: Marc Zyngier <marc.zyngier@arm•com>
> ---
> drivers/irqchip/irq-gic.c | 48 +++++++++++++++++++++++++++++++++++++++++------
> 1 file changed, 42 insertions(+), 6 deletions(-)
[...]
> +static void gic_irq_set_fwd_state(struct irq_data *d, u32 val, u32 mask)
> +{
> + if (mask & IRQ_FWD_STATE_PENDING)
> + gic_poke_irq(d, (val & IRQ_FWD_STATE_PENDING) ? GIC_DIST_ENABLE_SET : GIC_DIST_ENABLE_CLEAR);
> + if (mask & IRQ_FWD_STATE_ACTIVE)
> + gic_poke_irq(d, (val & IRQ_FWD_STATE_ACTIVE) ? GIC_DIST_ACTIVE_SET : GIC_DIST_ACTIVE_CLEAR);
> + if (mask & IRQ_FWD_STATE_MASKED)
> + gic_poke_irq(d, (val & IRQ_FWD_STATE_MASKED) ? GIC_DIST_ENABLE_CLEAR : GIC_DIST_ENABLE_SET);
Given that this isn't atomic and KVM only cares about ACTIVE, why not change
mask to be a single state only? Renumbering the states so that's not bits
would help to enforce this (i.e. make IRQ_FWD_STATE_ACTIVE 0, PENDING 1,
...).
That would also allow you to switch on the state and return early.
> +static u32 gic_irq_get_fwd_state(struct irq_data *d, u32 mask)
> +{
> + u32 val = 0;
> +
> + if (mask & IRQ_FWD_STATE_PENDING && gic_peek_irq(d, GIC_DIST_ENABLE_SET))
> + val |= IRQ_FWD_STATE_PENDING;
> + if (mask & IRQ_FWD_STATE_ACTIVE && gic_peek_irq(d, GIC_DIST_ACTIVE_SET))
> + val |= IRQ_FWD_STATE_ACTIVE;
> + if (mask & IRQ_FWD_STATE_MASKED && !gic_peek_irq(d, GIC_DIST_ENABLE_SET))
> + val |= IRQ_FWD_STATE_MASKED;
*and* you could peek GIC_DIST_ENABLE_SET in one place here.
Will
next prev parent reply other threads:[~2014-06-27 13:17 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-06-25 9:28 [RFC PATCH 0/9] ARM: Forwarding physical interrupts to a guest VM Marc Zyngier
2014-06-25 9:28 ` [RFC PATCH 1/9] genirq: Add IRQD_IRQ_FORWARDED flag and accessors Marc Zyngier
2014-06-25 9:28 ` [RFC PATCH 2/9] genirq: Allow the state of a forwarded irq to be save/restored Marc Zyngier
2014-06-27 13:10 ` Will Deacon
2014-07-07 8:40 ` Marc Zyngier
2014-06-25 9:28 ` [RFC PATCH 3/9] irqchip: GIC: Convert to EOImode == 1 Marc Zyngier
2014-06-25 12:50 ` Rob Herring
2014-06-25 13:03 ` Marc Zyngier
2014-06-25 13:18 ` Rob Herring
2014-06-25 13:56 ` Anup Patel
2014-06-25 14:03 ` Ian Campbell
2014-06-25 14:31 ` Marc Zyngier
2014-06-25 14:08 ` Rob Herring
2014-06-25 14:24 ` Marc Zyngier
2014-06-25 14:27 ` Ian Campbell
2014-06-25 20:14 ` Joel Schopp
2014-06-30 19:09 ` Stefano Stabellini
2014-07-01 8:24 ` Marc Zyngier
2014-07-01 16:34 ` Stefano Stabellini
2014-07-01 16:42 ` Marc Zyngier
2014-06-25 14:06 ` Peter Maydell
2014-06-25 14:46 ` Marc Zyngier
2014-08-06 11:30 ` Christoffer Dall
2014-07-25 12:42 ` Eric Auger
2014-06-25 9:28 ` [RFC PATCH 4/9] irqchip: GIC: add support for forwarded interrupts Marc Zyngier
2014-06-27 13:17 ` Will Deacon [this message]
2014-07-07 10:43 ` Marc Zyngier
2014-08-06 11:30 ` Christoffer Dall
2014-06-25 9:28 ` [RFC PATCH 5/9] irqchip: GICv3: Convert to EOImode == 1 Marc Zyngier
2014-06-25 9:28 ` [RFC PATCH 6/9] irqchip: GICv3: add support for forwarded interrupts Marc Zyngier
2014-06-25 9:28 ` [RFC PATCH 7/9] KVM: arm: vgic: allow dynamic mapping of physical/virtual interrupts Marc Zyngier
2014-08-03 9:48 ` Eric Auger
2014-08-04 13:13 ` Marc Zyngier
2014-08-07 15:47 ` Eric Auger
2014-08-11 8:01 ` Christoffer Dall
2014-08-11 13:22 ` Eric Auger
2014-06-25 9:28 ` [RFC PATCH 8/9] arm: KVM: timer: move the timer switch into the non-preemptible section Marc Zyngier
2014-06-25 9:28 ` [RFC PATCH 9/9] KVM: arm: timer: make the interrupt state part of the timer state Marc Zyngier
2014-06-25 14:52 ` [RFC PATCH 0/9] ARM: Forwarding physical interrupts to a guest VM Eric Auger
2014-06-26 9:31 ` Marc Zyngier
2014-06-26 12:58 ` Eric Auger
2014-06-26 14:12 ` Marc Zyngier
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