Re: [PATCH 03/10] xen/arm: Setup MMIO range trap handlers for hardware domain

From: Oleksandr Andrushchenko <Oleksandr_Andrushchenko@epam.com>
To: "Roger Pau Monné" <roger.pau@citrix.com>,
	"Oleksandr Andrushchenko" <andr2000@gmail.com>
Cc: "Rahul.Singh@arm.com" <Rahul.Singh@arm.com>,
	"Bertrand.Marquis@arm.com" <Bertrand.Marquis@arm.com>,
	"julien.grall@arm.com" <julien.grall@arm.com>,
	"jbeulich@suse.com" <jbeulich@suse.com>,
	"sstabellini@kernel.org" <sstabellini@kernel.org>,
	"xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org>,
	"iwj@xenproject.org" <iwj@xenproject.org>,
	"wl@xen.org" <wl@xen.org>
Subject: Re: [PATCH 03/10] xen/arm: Setup MMIO range trap handlers for hardware domain
Date: Wed, 11 Nov 2020 14:42:56 +0000	[thread overview]
Message-ID: <064408c9-6585-0aaf-aaed-f67910b27bf7@epam.com> (raw)
In-Reply-To: <20201111143924.gxbi5oopfeammgti@Air-de-Roger>

On 11/11/20 4:39 PM, Roger Pau Monné wrote:
> On Mon, Nov 09, 2020 at 02:50:24PM +0200, Oleksandr Andrushchenko wrote:
>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>
>> In order vPCI to work it needs all access to PCI configuration space
>> access to be synchronized among all entities, e.g. hardware domain and
>> guests. For that implement PCI host bridge specific callbacks to
>> propelry setup those ranges depending on host bridge implementation.
>>
>> This callback is optional and may not be used by non-ECAM host bridges.
>>
>> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>> ---
>>   xen/arch/arm/pci/pci-host-common.c  | 16 ++++++++++++++++
>>   xen/arch/arm/pci/pci-host-generic.c | 15 +++++++++++++--
>>   xen/arch/arm/vpci.c                 | 16 +++++++++++++++-
> So this is based on top of another series, maybe it would make sense
> to post those together, or else it's hard to get the right context.

This is based on ARM's PCI passthrough RFC series [1]

You can also see the whole picture at [2]

>
>>   xen/include/asm-arm/pci.h           |  7 +++++++
>>   4 files changed, 51 insertions(+), 3 deletions(-)
>>
>> diff --git a/xen/arch/arm/pci/pci-host-common.c b/xen/arch/arm/pci/pci-host-common.c
>> index b011c7eff3c8..b81184d34980 100644
>> --- a/xen/arch/arm/pci/pci-host-common.c
>> +++ b/xen/arch/arm/pci/pci-host-common.c
>> @@ -219,6 +219,22 @@ struct device *pci_find_host_bridge_device(struct device *dev)
>>       }
>>       return dt_to_dev(bridge->dt_node);
>>   }
>> +
>> +int pci_host_iterate_bridges(struct domain *d,
>> +                             int (*clb)(struct domain *d,
>> +                                        struct pci_host_bridge *bridge))
>> +{
>> +    struct pci_host_bridge *bridge;
>> +    int err;
>> +
>> +    list_for_each_entry( bridge, &pci_host_bridges, node )
>> +    {
>> +        err = clb(d, bridge);
>> +        if ( err )
>> +            return err;
>> +    }
>> +    return 0;
>> +}
>>   /*
>>    * Local variables:
>>    * mode: C
>> diff --git a/xen/arch/arm/pci/pci-host-generic.c b/xen/arch/arm/pci/pci-host-generic.c
>> index 54dd123e95c7..469df3da0116 100644
>> --- a/xen/arch/arm/pci/pci-host-generic.c
>> +++ b/xen/arch/arm/pci/pci-host-generic.c
>> @@ -85,12 +85,23 @@ int pci_ecam_config_read(struct pci_host_bridge *bridge, uint32_t sbdf,
>>       return 0;
>>   }
>>   
>> +static int pci_ecam_register_mmio_handler(struct domain *d,
>> +                                          struct pci_host_bridge *bridge,
> I think you can also constify bridge here.
Makes sense
>
> Thanks, Roger.

Thank you,

Oleksandr

[1] https://www.mail-archive.com/xen-devel@lists.xenproject.org/msg84452.html

[2] https://github.com/andr2000/xen/tree/vpci_rfc