Re: [kvm-unit-tests PATCH v3 09/14] arm/arm64: ITS: Device and collection Initialization

[Auger Eric]

Hi Drew,

On 2/7/20 1:51 PM, Andrew Jones wrote:
> On Tue, Jan 28, 2020 at 11:34:54AM +0100, 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 <address@hidden>
>>
>> ---
>>
>> v2 -> v3:
>> - s/report_abort/assert
>>
>> v1 -> v2:
>> - s/nb_/nr_
>> ---
>>  lib/arm/asm/gic-v3-its.h | 20 +++++++++++++++++-
>>  lib/arm/gic-v3-its.c     | 44 ++++++++++++++++++++++++++++++++++++++++
>>  2 files changed, 63 insertions(+), 1 deletion(-)
>>
>> diff --git a/lib/arm/asm/gic-v3-its.h b/lib/arm/asm/gic-v3-its.h
>> index fe73c04..acd97a9 100644
>> --- a/lib/arm/asm/gic-v3-its.h
>> +++ b/lib/arm/asm/gic-v3-its.h
>> @@ -31,6 +31,19 @@ struct its_baser {
>>  };
>>  
>>  #define GITS_BASER_NR_REGS              8
>> +#define GITS_MAX_DEVICES            8
>> +#define GITS_MAX_COLLECTIONS                8
>> +
>> +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;
>> @@ -38,6 +51,10 @@ struct its_data {
>>      struct its_baser baser[GITS_BASER_NR_REGS];
>>      struct its_cmd_block *cmd_base;
>>      struct its_cmd_block *cmd_write;
>> +    struct its_device devices[GITS_MAX_DEVICES];
>> +    u32 nr_devices;         /* Allocated Devices */
>> +    struct its_collection collections[GITS_MAX_COLLECTIONS];
>> +    u32 nr_collections;     /* Allocated Collections */
>>  };
>>  
>>  extern struct its_data its_data;
>> @@ -90,7 +107,6 @@ extern struct its_data its_data;
>>  #define GITS_BASER_TYPE_DEVICE              1
>>  #define GITS_BASER_TYPE_COLLECTION  4
>>  
>> -
>>  struct its_cmd_block {
>>      u64 raw_cmd[4];
>>  };
>> @@ -100,6 +116,8 @@ extern void its_init(void);
>>  extern int its_parse_baser(int i, struct its_baser *baser);
>>  extern struct its_baser *its_lookup_baser(int type);
>>  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);
>>  
>>  #else /* __arm__ */
>>  
>> diff --git a/lib/arm/gic-v3-its.c b/lib/arm/gic-v3-its.c
>> index d1e7e52..c2dcd01 100644
>> --- a/lib/arm/gic-v3-its.c
>> +++ b/lib/arm/gic-v3-its.c
>> @@ -175,3 +175,47 @@ 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;
>> +
>> +    assert(its_data.nr_devices < GITS_MAX_DEVICES);
>> +
>> +    baser = its_lookup_baser(GITS_BASER_TYPE_DEVICE);
>> +    if (!baser)
>> +            return NULL;
> 
> Should we assert here if we can't find a GITS_BASER_TYPE_DEVICE ?
> It seems none of the callers of its_create_device are checking
> for null.
I removed that code which is useless.
> 
>> +
>> +    new = &its_data.devices[its_data.nr_devices];
>> +
>> +    new->device_id = device_id;
>> +    new->nr_ites = nr_ites;
>> +
>> +    n = (its_data.typer.ite_size * nr_ites) >> PAGE_SHIFT;
>> +    order = is_power_of_2(n) ? fls(n) : fls(n) + 1;
> 
> I've seen this calculation several times now, so I think an
> arch-neutral order calculator is in order:
> 
>  int get_order(size_t size);
> 
>> +    new->itt = (void *)virt_to_phys(alloc_pages(order));
I added this get_order helper in lib/alloc_page.h/c
> 
> If this is a physical address then shouldn't itt be phys_addr_t ?
> 
>> +
>> +    its_data.nr_devices++;
>> +    return new;
>> +}
ITT now is a GVA (void *).
>> +
>> +struct its_collection *its_create_collection(u32 col_id, u32 pe)
>> +{
>> +    struct its_collection *new;
>> +
>> +    assert(its_data.nr_collections < GITS_MAX_COLLECTIONS);
>> +
>> +    new = &its_data.collections[its_data.nr_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.nr_collections++;
>> +    return new;
>> +}
>> -- 
>> 2.20.1
>>
> 
> Thanks,
> drew 
> 
Thanks

Eric