diff options
| -rw-r--r-- | hw/nvram/xlnx-efuse.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/hw/nvram/xlnx-efuse.c b/hw/nvram/xlnx-efuse.c index fdfffaab99..655c40b8d1 100644 --- a/hw/nvram/xlnx-efuse.c +++ b/hw/nvram/xlnx-efuse.c @@ -143,6 +143,8 @@ static bool efuse_ro_bits_find(XlnxEFuse *s, uint32_t k) bool xlnx_efuse_set_bit(XlnxEFuse *s, unsigned int bit) { + uint32_t set, *row; + if (efuse_ro_bits_find(s, bit)) { g_autofree char *path = object_get_canonical_path(OBJECT(s)); @@ -152,8 +154,13 @@ bool xlnx_efuse_set_bit(XlnxEFuse *s, unsigned int bit) return false; } - s->fuse32[bit / 32] |= 1 << (bit % 32); - efuse_bdrv_sync(s, bit); + /* Avoid back-end write unless there is a real update */ + row = &s->fuse32[bit / 32]; + set = 1 << (bit % 32); + if (!(set & *row)) { + *row |= set; + efuse_bdrv_sync(s, bit); + } return true; } |