crypto: caam - Remove broken arc4 support

The arc4 algorithm requires storing state in the request context
in order to allow more than one encrypt/decrypt operation.  As this
driver does not seem to do that, it means that using it for more
than one operation is broken.

Fixes: eaed71a4 ("crypto: caam - add ecb(*) support")
Link: https://lore.kernel.org/linux-crypto/CAMj1kXGvMe_A_iQ43Pmygg9xaAM-RLy=_M=v+eg--8xNmv9P+w@mail.gmail.com
Link: https://lore.kernel.org/linux-crypto/20200702101947.682-1-ardb@kernel.orgSigned-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/caam/caamalg.c

@@ -810,12 +810,6 @@ static int ctr_skcipher_setkey(struct crypto_skcipher *skcipher,
 	return skcipher_setkey(skcipher, key, keylen, ctx1_iv_off);
 }
 
-static int arc4_skcipher_setkey(struct crypto_skcipher *skcipher,
-				const u8 *key, unsigned int keylen)
-{
-	return skcipher_setkey(skcipher, key, keylen, 0);
-}
-
 static int des_skcipher_setkey(struct crypto_skcipher *skcipher,
 			       const u8 *key, unsigned int keylen)
 {
@@ -1967,21 +1961,6 @@ static struct caam_skcipher_alg driver_algs[] = {
 		},
 		.caam.class1_alg_type = OP_ALG_ALGSEL_3DES | OP_ALG_AAI_ECB,
 	},
-	{
-		.skcipher = {
-			.base = {
-				.cra_name = "ecb(arc4)",
-				.cra_driver_name = "ecb-arc4-caam",
-				.cra_blocksize = ARC4_BLOCK_SIZE,
-			},
-			.setkey = arc4_skcipher_setkey,
-			.encrypt = skcipher_encrypt,
-			.decrypt = skcipher_decrypt,
-			.min_keysize = ARC4_MIN_KEY_SIZE,
-			.max_keysize = ARC4_MAX_KEY_SIZE,
-		},
-		.caam.class1_alg_type = OP_ALG_ALGSEL_ARC4 | OP_ALG_AAI_ECB,
-	},
 };
 
 static struct caam_aead_alg driver_aeads[] = {
@@ -3457,7 +3436,6 @@ int caam_algapi_init(struct device *ctrldev)
 	struct caam_drv_private *priv = dev_get_drvdata(ctrldev);
 	int i = 0, err = 0;
 	u32 aes_vid, aes_inst, des_inst, md_vid, md_inst, ccha_inst, ptha_inst;
-	u32 arc4_inst;
 	unsigned int md_limit = SHA512_DIGEST_SIZE;
 	bool registered = false, gcm_support;
 
@@ -3477,8 +3455,6 @@ int caam_algapi_init(struct device *ctrldev)
 			   CHA_ID_LS_DES_SHIFT;
 		aes_inst = cha_inst & CHA_ID_LS_AES_MASK;
 		md_inst = (cha_inst & CHA_ID_LS_MD_MASK) >> CHA_ID_LS_MD_SHIFT;
-		arc4_inst = (cha_inst & CHA_ID_LS_ARC4_MASK) >>
-			    CHA_ID_LS_ARC4_SHIFT;
 		ccha_inst = 0;
 		ptha_inst = 0;
 
@@ -3499,7 +3475,6 @@ int caam_algapi_init(struct device *ctrldev)
 		md_inst = mdha & CHA_VER_NUM_MASK;
 		ccha_inst = rd_reg32(&priv->ctrl->vreg.ccha) & CHA_VER_NUM_MASK;
 		ptha_inst = rd_reg32(&priv->ctrl->vreg.ptha) & CHA_VER_NUM_MASK;
-		arc4_inst = rd_reg32(&priv->ctrl->vreg.afha) & CHA_VER_NUM_MASK;
 
 		gcm_support = aesa & CHA_VER_MISC_AES_GCM;
 	}
@@ -3522,10 +3497,6 @@ int caam_algapi_init(struct device *ctrldev)
 		if (!aes_inst && (alg_sel == OP_ALG_ALGSEL_AES))
 				continue;
 
-		/* Skip ARC4 algorithms if not supported by device */
-		if (!arc4_inst && alg_sel == OP_ALG_ALGSEL_ARC4)
-			continue;
-
 		/*
 		 * Check support for AES modes not available
 		 * on LP devices.

drivers/crypto/caam/compat.h

@@ -43,7 +43,6 @@
 #include <crypto/akcipher.h>
 #include <crypto/scatterwalk.h>
 #include <crypto/skcipher.h>
-#include <crypto/arc4.h>
 #include <crypto/internal/skcipher.h>
 #include <crypto/internal/hash.h>
 #include <crypto/internal/rsa.h>