[net-next PATCH] octeontx2-pf: cn10k/cn20k: Update count_eot in NPA_LF_AURA_BATCH_FREE0

[Geetha sowjanya <gakula@marvell.com>]

The count_eot field determines how many valid pointers are present in
the last 128-bit word during buffer free operations. The current driver
only handled CN10K devices where count_eot feild is 1 bit wide.
And possible values, count_eot = 0 for an even number of
pointers and 1 for an odd number.

For CN20K devices,the count_eot feild extended to 2 bits.
The hardware expects count_eot to represent the least
significant two bits of the number of valid pointers to free. This patch
updates the calculation accordingly to ensure correct behavior on both
CN10K and CN20K platforms.

Signed-off-by: Geetha sowjanya <gakula@marvell.com>
---
 .../net/ethernet/marvell/octeontx2/nic/otx2_common.h  | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
index 8cdfc36d79d2..c6023e1ce92b 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
@@ -789,8 +789,15 @@ static inline void __cn10k_aura_freeptr(struct otx2_nic *pfvf, u64 aura,
 	tar_addr = (__force u64)otx2_get_regaddr(pfvf, NPA_LF_AURA_BATCH_FREE0);
 	/* LMTID is same as AURA Id */
 	val = (lmt_info->lmt_id & 0x7FF) | BIT_ULL(63);
-	/* Set if [127:64] of last 128bit word has a valid pointer */
-	count_eot = (num_ptrs % 2) ? 0ULL : 1ULL;
+	/* Meaning of count_eot
+	 * CN10K: count_eot = 0 if the number of pointers to free is even,
+	 *	  count_eot = 1 if the number of pointers to free is odd.
+	 *
+	 * CN20K: count_eot represents the least significant 2 bits of the
+	 *	  total number of valid pointers to free.
+	 *        Example: if 7 pointers are freed (0b111), count_eot = 0b11.
+	 */
+	count_eot = (num_ptrs - 1) & 0x3ULL;
 	/* Set AURA ID to free pointer */
 	ptrs[0] = (count_eot << 32) | (aura & 0xFFFFF);
 	/* Target address for LMTST flush tells HW how many 128bit
-- 
2.25.1