[PATCH] winex11.drv: Add VRAM size to GPU hardware information if available.

[Paul Gofman]

On 10/19/21 14:58, Zhiyi Zhang wrote:
>
> I wonder if we can add all heaps with VK_MEMORY_HEAP_DEVICE_LOCAL_BIT together and get the total vram.

VK_MEMORY_HEAP_DEVICE_LOCAL_BIT is set nowadays in Vulkan for a heap 
corresponding to a real device local memory (or what integrated GPU 
driver things reasonable to expose as such) and also for a heap 
corresponding to BAR memory (which is much smaller).

My RX 580 has 8GB local video memory and that is exactly what I see on 
Windows 10 for it in this registry field. Vulkan reports 0x1f0000000 
local heap and 0x10000000 (256MB) host coherent heap, so looking at this 
particular case adding those would make sense. However, this is 
different for Nvidia with 8GB here: Vulkan reports exactly 8GB as device 
local heap and additionally 256MB in host coherent heap. So, given those 
differences it seems more straightforward to me to report a single heap, 
even if with the current Vulkan drivers for AMD discrete card it ends up 
256MB less.

Also, we could potentially distinguish between those heaps by exploring 
memory types corresponding to the heap (MEMORY_PROPERTY_HOST_VISIBLE_BIT 
on memory type suggests that is BAR memory), but I didn't go this way 
(checking memory types) as it might make things twisted for integrated GPUs.

>
> Also, what does Windows report for integrated graphics?
>
>
I suppose it might be integrated graphics dependent. I only have Windows 
7 laptop with (quite old) integrated Intel / discrete Nvidia and 
registry field reports around 2GB. I don't have Linux on the same 
machine but here with a newer Intel integrated GPU Linux Vulkan reports 
a single 2GB heap (VK_MEMORY_HEAP_DEVICE_LOCAL_BIT with a single memory 
type of MEMORY_PROPERTY_DEVICE_LOCAL_BIT | 
MEMORY_PROPERTY_HOST_VISIBLE_BIT | MEMORY_PROPERTY_HOST_COHERENT_BIT | 
MEMORY_PROPERTY_HOST_CACHED_BIT (that is, it is generally 
indistinguishable from BAR memory reporting on discrete GPU thus my 
unwillingness to guess the memory type explicitly).

It is less straightforward what is VRAM for integrated GPU but I believe 
it is (Vulkan and GL) driver responsibility to advertise a reasonable 
device local heap info which should match what system specs as "VRAM 
size" as a single value.