5.15-stable review patch. If anyone has any objections, please let me know.
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From: Sudheer Kumar Doredla s-doredla@ti.com
[ Upstream commit 03d120f27d050336f7e7d21879891542c4741f81 ]
CPSW ALE has 75-bit ALE entries stored across three 32-bit words. The cpsw_ale_get_field() and cpsw_ale_set_field() functions support ALE field entries spanning up to two words at the most.
The cpsw_ale_get_field() and cpsw_ale_set_field() functions work as expected when ALE field spanned across word1 and word2, but fails when ALE field spanned across word2 and word3.
For example, while reading the ALE field spanned across word2 and word3 (i.e. bits 62 to 64), the word3 data shifted to an incorrect position due to the index becoming zero while flipping. The same issue occurred when setting an ALE entry.
This issue has not been seen in practice but will be an issue in the future if the driver supports accessing ALE fields spanning word2 and word3
Fix the methods to handle getting/setting fields spanning up to two words.
Fixes: b685f1a58956 ("net: ethernet: ti: cpsw_ale: Fix cpsw_ale_get_field()/cpsw_ale_set_field()") Signed-off-by: Sudheer Kumar Doredla s-doredla@ti.com Reviewed-by: Simon Horman horms@kernel.org Reviewed-by: Roger Quadros rogerq@kernel.org Reviewed-by: Siddharth Vadapalli s-vadapalli@ti.com Link: https://patch.msgid.link/20250108172433.311694-1-s-doredla@ti.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/ti/cpsw_ale.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/ti/cpsw_ale.c b/drivers/net/ethernet/ti/cpsw_ale.c index 8c59e34d8bcaf..348a05454fcaa 100644 --- a/drivers/net/ethernet/ti/cpsw_ale.c +++ b/drivers/net/ethernet/ti/cpsw_ale.c @@ -104,15 +104,15 @@ struct cpsw_ale_dev_id {
static inline int cpsw_ale_get_field(u32 *ale_entry, u32 start, u32 bits) { - int idx, idx2; + int idx, idx2, index; u32 hi_val = 0;
idx = start / 32; idx2 = (start + bits - 1) / 32; /* Check if bits to be fetched exceed a word */ if (idx != idx2) { - idx2 = 2 - idx2; /* flip */ - hi_val = ale_entry[idx2] << ((idx2 * 32) - start); + index = 2 - idx2; /* flip */ + hi_val = ale_entry[index] << ((idx2 * 32) - start); } start -= idx * 32; idx = 2 - idx; /* flip */ @@ -122,16 +122,16 @@ static inline int cpsw_ale_get_field(u32 *ale_entry, u32 start, u32 bits) static inline void cpsw_ale_set_field(u32 *ale_entry, u32 start, u32 bits, u32 value) { - int idx, idx2; + int idx, idx2, index;
value &= BITMASK(bits); idx = start / 32; idx2 = (start + bits - 1) / 32; /* Check if bits to be set exceed a word */ if (idx != idx2) { - idx2 = 2 - idx2; /* flip */ - ale_entry[idx2] &= ~(BITMASK(bits + start - (idx2 * 32))); - ale_entry[idx2] |= (value >> ((idx2 * 32) - start)); + index = 2 - idx2; /* flip */ + ale_entry[index] &= ~(BITMASK(bits + start - (idx2 * 32))); + ale_entry[index] |= (value >> ((idx2 * 32) - start)); } start -= idx * 32; idx = 2 - idx; /* flip */