| 1 | // SPDX-License-Identifier: GPL-2.0 |
|---|---|
| 2 | /* |
| 3 | * Copyright IBM Corp. 2023 |
| 4 | */ |
| 5 | |
| 6 | #include <linux/export.h> |
| 7 | #include <asm/facility.h> |
| 8 | |
| 9 | unsigned int stfle_size(void) |
| 10 | { |
| 11 | static unsigned int size; |
| 12 | unsigned int r; |
| 13 | u64 dummy; |
| 14 | |
| 15 | r = READ_ONCE(size); |
| 16 | if (!r) { |
| 17 | r = __stfle_asm(&dummy, 1) + 1; |
| 18 | WRITE_ONCE(size, r); |
| 19 | } |
| 20 | return r; |
| 21 | } |
| 22 | EXPORT_SYMBOL(stfle_size); |
| 23 |