habanalabs: report correct dram size in info ioctl

In case MMU is enabled, we must take MMU page size into
consideration when reporting dram size to the user.
This is because the MMU page size can be a value which is NOT
a power-of-2 value. As a result, the total DRAM size (which is always
a power-of-2 value) needed to be rounded-down.
Signed-off-by: NOfir Bitton <obitton@habana.ai>
Reviewed-by: NOded Gabbay <ogabbay@kernel.org>
Signed-off-by: NOded Gabbay <ogabbay@kernel.org>

drivers/misc/habanalabs/common/habanalabs_ioctl.c

@@ -62,7 +62,15 @@ static int hw_ip_info(struct hl_device *hdev, struct hl_info_args *args)
 			prop->dmmu.start_addr : prop->dram_user_base_address;
 	hw_ip.tpc_enabled_mask = prop->tpc_enabled_mask;
 	hw_ip.sram_size = prop->sram_size - sram_kmd_size;
-	hw_ip.dram_size = prop->dram_size - dram_kmd_size;
+
+	if (hdev->mmu_enable)
+		hw_ip.dram_size =
+			DIV_ROUND_DOWN_ULL(prop->dram_size - dram_kmd_size,
+						prop->dram_page_size) *
+							prop->dram_page_size;
+	else
+		hw_ip.dram_size = prop->dram_size - dram_kmd_size;
+
 	if (hw_ip.dram_size > PAGE_SIZE)
 		hw_ip.dram_enabled = 1;
 	hw_ip.dram_page_size = prop->dram_page_size;