crypto: chcr - Add fallback for AEAD algos

Fallback to sw when
    I AAD length greater than 511
    II Zero length payload
    II No of sg entries exceeds Request size.
Signed-off-by: Harsh Jain <harsh@chelsio.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/chelsio/chcr_algo.h

@@ -218,6 +218,10 @@
 
 #define MAX_NK 8
 #define CRYPTO_MAX_IMM_TX_PKT_LEN 256
+#define MAX_WR_SIZE			512
+#define MIN_AUTH_SG			2 /*IV + AAD*/
+#define MIN_GCM_SG			2 /* IV + AAD*/
+#define MIN_CCM_SG			3 /*IV+AAD+B0*/
 
 struct algo_param {
 	unsigned int auth_mode;

drivers/crypto/chelsio/chcr_crypto.h

@@ -41,7 +41,7 @@
 
 #define CCM_B0_SIZE             16
 #define CCM_AAD_FIELD_SIZE      2
-#define T5_MAX_AAD_SIZE 512
+#define T6_MAX_AAD_SIZE 511
 
 
 /* Define following if h/w is not dropping the AAD and IV data before
@@ -188,6 +188,7 @@ struct chcr_aead_ctx {
 	__be32 key_ctx_hdr;
 	unsigned int enckey_len;
 	struct crypto_skcipher *null;
+	struct crypto_aead *sw_cipher;
 	u8 salt[MAX_SALT];
 	u8 key[CHCR_AES_MAX_KEY_LEN];
 	u16 hmac_ctrl;