Re: [kvm-unit-tests PATCH 11/16] arm/arm64: ITS: Device and collection Initialization

[Auger Eric <eric.auger@redhat.com>]

Hi Zenghui,

On 12/20/19 8:25 AM, Zenghui Yu wrote:
> Hi Eric,
> 
> On 2019/12/16 22:02, Eric Auger wrote:
>> Introduce an helper functions to register
>> - a new device, characterized by its device id and the
>>    max number of event IDs that dimension its ITT (Interrupt
>>    Translation Table).  The function allocates the ITT.
>>
>> - a new collection, characterized by its ID and the
>>    target processing engine (PE).
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>>
>> ---
>> ---
>>   lib/arm/asm/gic-v3-its.h | 20 +++++++++++++++++
>>   lib/arm/gic-v3-its.c     | 46 ++++++++++++++++++++++++++++++++++++++++
>>   2 files changed, 66 insertions(+)
>>
>> diff --git a/lib/arm/asm/gic-v3-its.h b/lib/arm/asm/gic-v3-its.h
>> index ab639c5..245ef61 100644
>> --- a/lib/arm/asm/gic-v3-its.h
>> +++ b/lib/arm/asm/gic-v3-its.h
>> @@ -87,6 +87,9 @@
>>     #define ITS_FLAGS_CMDQ_NEEDS_FLUSHING           (1ULL << 0)
>>   +#define GITS_MAX_DEVICES        8
>> +#define GITS_MAX_COLLECTIONS        8
>> +
>>   struct its_typer {
>>       unsigned int ite_size;
>>       unsigned int eventid_bits;
>> @@ -117,6 +120,17 @@ struct its_cmd_block {
>>       u64     raw_cmd[4];
>>   };
>>   +struct its_device {
>> +    u32 device_id;    /* device ID */
>> +    u32 nr_ites;    /* Max Interrupt Translation Entries */
>> +    void *itt;    /* Interrupt Translation Table GPA */
>> +};
>> +
>> +struct its_collection {
>> +    u64 target_address;
>> +    u16 col_id;
>> +};
>> +
>>   struct its_data {
>>       void *base;
>>       struct its_typer typer;
>> @@ -124,6 +138,10 @@ struct its_data {
>>       struct its_cmd_block *cmd_base;
>>       struct its_cmd_block *cmd_write;
>>       struct its_cmd_block *cmd_readr;
>> +    struct its_device devices[GITS_MAX_DEVICES];
>> +    u32 nb_devices;        /* Allocated Devices */
>> +    struct its_collection collections[GITS_MAX_COLLECTIONS];
>> +    u32 nb_collections;    /* Allocated Collections */
> 
> ('nr_*' may be the more widely used one.)
> 
>>   };
>>     extern struct its_data its_data;
>> @@ -140,6 +158,8 @@ extern u8 get_lpi_config(int n);
>>   extern void set_pending_table_bit(int rdist, int n, bool set);
>>   extern void gicv3_rdist_ctrl_lpi(u32 redist, bool set);
>>   extern void its_enable_defaults(void);
>> +extern struct its_device *its_create_device(u32 dev_id, int nr_ites);
>> +extern struct its_collection *its_create_collection(u32 col_id, u32
>> target_pe);
>>     #endif /* !__ASSEMBLY__ */
>>   #endif /* _ASMARM_GIC_V3_ITS_H_ */
>> diff --git a/lib/arm/gic-v3-its.c b/lib/arm/gic-v3-its.c
>> index 9a51ef4..9906428 100644
>> --- a/lib/arm/gic-v3-its.c
>> +++ b/lib/arm/gic-v3-its.c
>> @@ -284,3 +284,49 @@ void its_enable_defaults(void)
>>         writel(GITS_CTLR_ENABLE, its_data.base + GITS_CTLR);
>>   }
>> +
>> +struct its_device *its_create_device(u32 device_id, int nr_ites)
>> +{
>> +    struct its_baser *baser;
>> +    struct its_device *new;
>> +    unsigned long n, order;
>> +
>> +    if (its_data.nb_devices >= GITS_MAX_DEVICES)
>> +        report_abort("%s redimension GITS_MAX_DEVICES", __func__);
>> +
>> +    baser = its_lookup_baser(GITS_BASER_TYPE_DEVICE);
>> +    if (!baser)
>> +        return NULL;
>> +
>> +    new = &its_data.devices[its_data.nb_devices];
>> +
>> +    new->device_id = device_id;
>> +    new->nr_ites = nr_ites;
>> +
>> +    n = (baser->esz * nr_ites) >> PAGE_SHIFT;
> 
> baser->esz is GITS_BASER.Entry_Size, which indicates the size of
> Device Table entry.
> We're allocating ITT for this device now, shouldn't we use
> its_data.typer.esz?

Yes you're definitively right. I should use its_data.typer.ite_size.

Thank you!

Eric
> 
> 
> Thanks,
> Zenghui
> 
>> +    order = is_power_of_2(n) ? fls(n) : fls(n) + 1;
>> +    new->itt = (void *)virt_to_phys(alloc_pages(order));
>> +
>> +    its_data.nb_devices++;
>> +    return new;
>> +}
>> +
>> +struct its_collection *its_create_collection(u32 col_id, u32 pe)
>> +{
>> +    struct its_collection *new;
>> +
>> +    if (its_data.nb_collections >= GITS_MAX_COLLECTIONS)
>> +        report_abort("%s redimension GITS_MAX_COLLECTIONS", __func__);
>> +
>> +    new = &its_data.collections[its_data.nb_collections];
>> +
>> +    new->col_id = col_id;
>> +
>> +    if (its_data.typer.pta)
>> +        new->target_address = (u64)gicv3_data.redist_base[pe];
>> +    else
>> +        new->target_address = pe << 16;
>> +
>> +    its_data.nb_collections++;
>> +    return new;
>> +}
>>
>