habanalabs: support reserving aligned va block

Add support for reserving va block with alignment different than
page size. This is a pre-requisite for allocations needed in future
ASICs
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.h

@@ -303,6 +303,8 @@ enum hl_device_hw_state {
 	HL_DEVICE_HW_STATE_DIRTY
 };
 
+#define HL_MMU_VA_ALIGNMENT_NOT_NEEDED 0
+
 /**
  * struct hl_mmu_properties - ASIC specific MMU address translation properties.
  * @start_addr: virtual start address of the memory region.
@@ -2112,7 +2114,7 @@ int hl_vm_init(struct hl_device *hdev);
 void hl_vm_fini(struct hl_device *hdev);
 
 u64 hl_reserve_va_block(struct hl_device *hdev, struct hl_ctx *ctx,
-		enum hl_va_range_type type, u32 size);
+		enum hl_va_range_type type, u32 size, u32 alignment);
 int hl_unreserve_va_block(struct hl_device *hdev, struct hl_ctx *ctx,
 		u64 start_addr, u64 size);
 int hl_pin_host_memory(struct hl_device *hdev, u64 addr, u64 size,

drivers/misc/habanalabs/common/memory.c

@@ -626,18 +626,20 @@ static u64 get_va_block(struct hl_device *hdev, struct hl_va_range *va_range,
  * @ctx: current context
  * @type: virtual addresses range type.
  * @size: requested block size.
+ * @alignment: required alignment in bytes of the virtual block start address,
+ *             0 means no alignment.
  *
  * This function does the following:
  * - Iterate on the virtual block list to find a suitable virtual block for the
- *   given size.
+ *   given size and alignment.
  * - Reserve the requested block and update the list.
  * - Return the start address of the virtual block.
  */
 u64 hl_reserve_va_block(struct hl_device *hdev, struct hl_ctx *ctx,
-		enum hl_va_range_type type, u32 size)
+		enum hl_va_range_type type, u32 size, u32 alignment)
 {
 	return get_va_block(hdev, ctx->va_range[type], size, 0,
-			ctx->va_range[type]->page_size);
+			max(alignment, ctx->va_range[type]->page_size));
 }
 
 /**

drivers/misc/habanalabs/gaudi/gaudi.c

@@ -7791,7 +7791,8 @@ static int gaudi_internal_cb_pool_init(struct hl_device *hdev,
 	}
 
 	hdev->internal_cb_va_base = hl_reserve_va_block(hdev, ctx,
-			HL_VA_RANGE_TYPE_HOST, HOST_SPACE_INTERNAL_CB_SZ);
+			HL_VA_RANGE_TYPE_HOST, HOST_SPACE_INTERNAL_CB_SZ,
+			HL_MMU_VA_ALIGNMENT_NOT_NEEDED);
 
 	if (!hdev->internal_cb_va_base)
 		goto destroy_internal_cb_pool;