Re: [igt-dev] [PATCH i-g-t 1/2] lib/i915/intel_memory_region: Add gem_has_smallbar

["Das, Nirmoy" <nirmoy.das@intel.com>]

On 1/23/2023 4:16 PM, Andrzej Hajda wrote:
>
>
> On 20.01.2023 11:07, Nirmoy Das wrote:
>> Add gem_has_smallbar() to detect a device with smallbar.
>>
>> Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
>> ---
>>   lib/i915/intel_memory_region.c | 32 ++++++++++++++++++++++++++++++++
>>   lib/i915/intel_memory_region.h |  1 +
>>   2 files changed, 33 insertions(+)
>>
>> diff --git a/lib/i915/intel_memory_region.c 
>> b/lib/i915/intel_memory_region.c
>> index 84e1bceb3..655720819 100644
>> --- a/lib/i915/intel_memory_region.c
>> +++ b/lib/i915/intel_memory_region.c
>> @@ -183,6 +183,38 @@ bool gem_has_lmem(int fd)
>>       return gem_get_lmem_region_count(fd) > 0;
>>   }
>>   +/**
>> + * gem_has_smallbar:
>> + * @fd: open i915 drm file descriptor
>> + *
>> + * Helper function to check if the device comes with small-bar.
>> + *
>> + * Returns: True if at least one lmem region was found.
>> + */
>> +bool gem_has_smallbar(int fd)
>> +{
>> +    struct drm_i915_query_memory_regions *info;
>> +    struct drm_i915_memory_region_info *rf;
>> +    bool ret = false;
>> +
>> +    info = gem_get_query_memory_regions(fd);
>> +    igt_assert(info);
>> +
>> +    for (int i = 0; i < info->num_regions; i++) {
>> +        rf = &info->regions[i];
>> +        if (rf->region.memory_class == I915_MEMORY_CLASS_DEVICE) {
>> +            if (rf->probed_size > rf->probed_cpu_visible_size) {
>> +                ret = true;
>> +                break;
>> +            }
>> +        }
>> +    }
>> +    free(info);
>
> Why not for_each_memory_region ?


No particular reason, it is inspired by existing code from the same 
file.  for_each_memory_region() though calls into 
gem_get_query_memory_regions() eventually.


Regards,

Nirmoy

>
> Regards
> Andrzej
>
>> +
>> +    return ret;
>> +}
>> +
>> +
>>   /* A version of gem_create_in_memory_region_list which can be 
>> allowed to
>>      fail so that the object creation can be retried */
>>   int __gem_create_in_memory_region_list(int fd, uint32_t *handle, 
>> uint64_t *size, uint32_t flags,
>> diff --git a/lib/i915/intel_memory_region.h 
>> b/lib/i915/intel_memory_region.h
>> index 425bda0ec..9e24bd8fb 100644
>> --- a/lib/i915/intel_memory_region.h
>> +++ b/lib/i915/intel_memory_region.h
>> @@ -62,6 +62,7 @@ struct drm_i915_query_memory_regions 
>> *gem_get_query_memory_regions(int fd);
>>   unsigned int gem_get_lmem_region_count(int fd);
>>     bool gem_has_lmem(int fd);
>> +bool gem_has_smallbar(int fd);
>>     int __gem_create_in_memory_region_list(int fd, uint32_t *handle, 
>> uint64_t *size, uint32_t flags,
>>                          const struct 
>> drm_i915_gem_memory_class_instance *mem_regions,
>