diff options
author | Harald Welte <laforge@gnumonks.org> | 2018-09-30 14:50:39 +0200 |
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committer | Harald Welte <laforge@gnumonks.org> | 2018-09-30 15:50:01 +0200 |
commit | 173555dab71d2bcd1e1984a2608e1dd7f0e77dc5 (patch) | |
tree | 7bddedb01c0b788ffda8132b42ce51a9898b8787 /include | |
parent | 2c1a46a2ddd306f0f6758d5d5af67534adf74c28 (diff) |
Fix computing CCCH block number from frame number
The existing implementation used a simplistic macro, which was wrong
in many ways:
1) it returned a negative value for "fn % 51 < 5" conditions without
raising any error message or asserting
2) it returned a wrong block number for many different input frame
numbers, as it didn't account properly for the FCCH/SCH gaps between
the blocks
Let's replace the simplistic macro with a proper lookup table based on
TS 05.02, and let's OSMO_ASSERT() if this is ever called with non-CCCH
frame numbers.
Change-Id: I11fd6cc558bb61c40c2019e46f56c1fe78ef39f5
Closes: OS#3024
Diffstat (limited to 'include')
-rw-r--r-- | include/osmo-bts/l1sap.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/osmo-bts/l1sap.h b/include/osmo-bts/l1sap.h index 3225a60f..e2c92fa2 100644 --- a/include/osmo-bts/l1sap.h +++ b/include/osmo-bts/l1sap.h @@ -29,7 +29,7 @@ #define L1SAP_IS_PACKET_RACH(ra) ((ra & 0xf0) == 0x70 && (ra & 0x0f) != 0x0f) /* CCCH block from frame number */ -#define L1SAP_FN2CCCHBLOCK(fn) ((fn % 51) / 5 - 1) +unsigned int l1sap_fn2ccch_block(uint32_t fn); /* PTCH layout from frame number */ #define L1SAP_FN2MACBLOCK(fn) ((fn % 52) / 4) |