[PATCH v2 18/54] KVM: arm/arm64: vgic-new: Add GICv3 world switch backend

[Marc Zyngier]

On 04/05/16 14:30, Andre Przywara wrote:
> Hi,
> 
> On 03/05/16 17:16, Marc Zyngier wrote:
>> On 28/04/16 17:45, Andre Przywara wrote:
>>> From: Marc Zyngier <marc.zyngier at arm.com>
>>>
>>> As the GICv3 virtual interface registers differ from their GICv2
>>> siblings, we need different handlers for processing maintenance
>>> interrupts and reading/writing to the LRs.
>>> Implement the respective handler functions and connect them to
>>> existing code to be called if the host is using a GICv3.
>>>
>>> Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
>>> Signed-off-by: Andre Przywara <andre.przywara at arm.com>
>>> ---
>>> Changelog RFC..v1:
>>> - remove outdated comment about the dist_lock
>>> - add WARN_ON about LR_STATE not being 0 in maintenance interrupts
>>>
>>> Changelog v1 .. v2:
>>> - inject the IRQ priority into the list register
>>>
>>>  include/linux/irqchip/arm-gic-v3.h |   1 +
>>>  virt/kvm/arm/vgic/vgic-v3.c        | 169 +++++++++++++++++++++++++++++++++++++
>>>  virt/kvm/arm/vgic/vgic.c           |  25 ++++--
>>>  virt/kvm/arm/vgic/vgic.h           |  29 +++++++
>>>  4 files changed, 219 insertions(+), 5 deletions(-)
>>>  create mode 100644 virt/kvm/arm/vgic/vgic-v3.c
>>>
>>> diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
>>> index d5d798b..56fd2c5 100644
>>> --- a/include/linux/irqchip/arm-gic-v3.h
>>> +++ b/include/linux/irqchip/arm-gic-v3.h
>>> @@ -275,6 +275,7 @@
>>>  #define ICH_LR_ACTIVE_BIT		(1ULL << 63)
>>>  #define ICH_LR_PHYS_ID_SHIFT		32
>>>  #define ICH_LR_PHYS_ID_MASK		(0x3ffULL << ICH_LR_PHYS_ID_SHIFT)
>>> +#define ICH_LR_PRIORITY_SHIFT		48
>>>  
>>>  #define ICH_MISR_EOI			(1 << 0)
>>>  #define ICH_MISR_U			(1 << 1)
>>> diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
>>> new file mode 100644
>>> index 0000000..461229b
>>> --- /dev/null
>>> +++ b/virt/kvm/arm/vgic/vgic-v3.c
>>> @@ -0,0 +1,169 @@
>>> +/*
>>> + * This program is free software; you can redistribute it and/or modify
>>> + * it under the terms of the GNU General Public License version 2 as
>>> + * published by the Free Software Foundation.
>>> + *
>>> + * This program is distributed in the hope that it will be useful,
>>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>>> + * GNU General Public License for more details.
>>> + *
>>> + * You should have received a copy of the GNU General Public License
>>> + * along with this program. If not, see <http://www.gnu.org/licenses/>.
>>> + */
>>> +
>>> +#include <linux/irqchip/arm-gic-v3.h>
>>> +#include <linux/kvm.h>
>>> +#include <linux/kvm_host.h>
>>> +#include <linux/irqchip/arm-gic.h>
>>
>> This last line is definitely a (copy-paste) bug. We should never include
>> both GIC headers in the same file. Can you please drop that line and
>> have the following hunk instead?
>>
>> +/* These are for GICv2 emulation only */
>> +#define GICH_LR_VIRTUALID		(0x3ffUL << 0)
>> +#define GICH_LR_PHYSID_CPUID_SHIFT	(10)
>> +#define GICH_LR_PHYSID_CPUID		(7UL << GICH_LR_PHYSID_CPUID_SHIFT)
>> +#define ICH_LR_VIRTUALID_MASK		(BIT_ULL(32) - 1)
>> +
> 
> What about including those lines (except the last one) in arm-gic-v3.h
> then? In fact they describe a property of an _GICv3_ LR, even if it is
> only a compatibility feature.
> That would be cleaner IMHO than repeating the definitions here in a .c
> file and we would automatically get the right definitions by just
> including arm-gic-v3.h.
> 
> This just compiled fine for me for both the old and new VGIC.
> I can send the patch (needs to be a separate patch because it touches
> the old VGIC as well) if you agree on that idea.

Sure, send the patch.

	M.
-- 
Jazz is not dead. It just smells funny...