crypto: caam - Detect hardware features during algorithm registration

Register only algorithms supported by CAAM hardware, using the CHA
version and instantiation registers to identify hardware capabilities.
Signed-off-by: Victoria Milhoan <vicki.milhoan@freescale.com>
Tested-by: Horia Geantă <horia.geanta@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/caam/caamalg.c

@@ -4371,8 +4371,10 @@ static int __init caam_algapi_init(void)
 	struct device_node *dev_node;
 	struct platform_device *pdev;
 	struct device *ctrldev;
-	void *priv;
+	struct caam_drv_private *priv;
 	int i = 0, err = 0;
+	u32 cha_vid, cha_inst, des_inst, aes_inst, md_inst;
+	unsigned int md_limit = SHA512_DIGEST_SIZE;
 	bool registered = false;
 
 	dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec-v4.0");
@@ -4402,16 +4404,39 @@ static int __init caam_algapi_init(void)
 
 	INIT_LIST_HEAD(&alg_list);
 
-	/* register crypto algorithms the device supports */
+	/*
+	 * Register crypto algorithms the device supports.
+	 * First, detect presence and attributes of DES, AES, and MD blocks.
+	 */
+	cha_vid = rd_reg32(&priv->ctrl->perfmon.cha_id_ls);
+	cha_inst = rd_reg32(&priv->ctrl->perfmon.cha_num_ls);
+	des_inst = (cha_inst & CHA_ID_LS_DES_MASK) >> CHA_ID_LS_DES_SHIFT;
+	aes_inst = (cha_inst & CHA_ID_LS_AES_MASK) >> CHA_ID_LS_AES_SHIFT;
+	md_inst = (cha_inst & CHA_ID_LS_MD_MASK) >> CHA_ID_LS_MD_SHIFT;
+
+	/* If MD is present, limit digest size based on LP256 */
+	if (md_inst && ((cha_vid & CHA_ID_LS_MD_MASK) == CHA_ID_LS_MD_LP256))
+		md_limit = SHA256_DIGEST_SIZE;
+
 	for (i = 0; i < ARRAY_SIZE(driver_algs); i++) {
-		/* TODO: check if h/w supports alg */
 		struct caam_crypto_alg *t_alg;
+		struct caam_alg_template *alg = driver_algs + i;
+		u32 alg_sel = alg->class1_alg_type & OP_ALG_ALGSEL_MASK;
+
+		/* Skip DES algorithms if not supported by device */
+		if (!des_inst &&
+		    ((alg_sel == OP_ALG_ALGSEL_3DES) ||
+		     (alg_sel == OP_ALG_ALGSEL_DES)))
+				continue;
+
+		/* Skip AES algorithms if not supported by device */
+		if (!aes_inst && (alg_sel == OP_ALG_ALGSEL_AES))
+				continue;
 
-		t_alg = caam_alg_alloc(&driver_algs[i]);
+		t_alg = caam_alg_alloc(alg);
 		if (IS_ERR(t_alg)) {
 			err = PTR_ERR(t_alg);
-			pr_warn("%s alg allocation failed\n",
-				driver_algs[i].driver_name);
+			pr_warn("%s alg allocation failed\n", alg->driver_name);
 			continue;
 		}
 
@@ -4429,6 +4454,37 @@ static int __init caam_algapi_init(void)
 
 	for (i = 0; i < ARRAY_SIZE(driver_aeads); i++) {
 		struct caam_aead_alg *t_alg = driver_aeads + i;
+		u32 c1_alg_sel = t_alg->caam.class1_alg_type &
+				 OP_ALG_ALGSEL_MASK;
+		u32 c2_alg_sel = t_alg->caam.class2_alg_type &
+				 OP_ALG_ALGSEL_MASK;
+		u32 alg_aai = t_alg->caam.class1_alg_type & OP_ALG_AAI_MASK;
+
+		/* Skip DES algorithms if not supported by device */
+		if (!des_inst &&
+		    ((c1_alg_sel == OP_ALG_ALGSEL_3DES) ||
+		     (c1_alg_sel == OP_ALG_ALGSEL_DES)))
+				continue;
+
+		/* Skip AES algorithms if not supported by device */
+		if (!aes_inst && (c1_alg_sel == OP_ALG_ALGSEL_AES))
+				continue;
+
+		/*
+		 * Check support for AES algorithms not available
+		 * on LP devices.
+		 */
+		if ((cha_vid & CHA_ID_LS_AES_MASK) == CHA_ID_LS_AES_LP)
+			if (alg_aai == OP_ALG_AAI_GCM)
+				continue;
+
+		/*
+		 * Skip algorithms requiring message digests
+		 * if MD or MD size is not supported by device.
+		 */
+		if (c2_alg_sel &&
+		    (!md_inst || (t_alg->aead.maxauthsize > md_limit)))
+				continue;
 
 		caam_aead_alg_init(t_alg);
 

drivers/crypto/caam/caamhash.c

@@ -1883,8 +1883,10 @@ static int __init caam_algapi_hash_init(void)
 	struct device_node *dev_node;
 	struct platform_device *pdev;
 	struct device *ctrldev;
-	void *priv;
 	int i = 0, err = 0;
+	struct caam_drv_private *priv;
+	unsigned int md_limit = SHA512_DIGEST_SIZE;
+	u32 cha_inst, cha_vid;
 
 	dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec-v4.0");
 	if (!dev_node) {
@@ -1910,19 +1912,40 @@ static int __init caam_algapi_hash_init(void)
 	if (!priv)
 		return -ENODEV;
 
+	/*
+	 * Register crypto algorithms the device supports.  First, identify
+	 * presence and attributes of MD block.
+	 */
+	cha_vid = rd_reg32(&priv->ctrl->perfmon.cha_id_ls);
+	cha_inst = rd_reg32(&priv->ctrl->perfmon.cha_num_ls);
+
+	/*
+	 * Skip registration of any hashing algorithms if MD block
+	 * is not present.
+	 */
+	if (!((cha_inst & CHA_ID_LS_MD_MASK) >> CHA_ID_LS_MD_SHIFT))
+		return -ENODEV;
+
+	/* Limit digest size based on LP256 */
+	if ((cha_vid & CHA_ID_LS_MD_MASK) == CHA_ID_LS_MD_LP256)
+		md_limit = SHA256_DIGEST_SIZE;
+
 	INIT_LIST_HEAD(&hash_list);
 
 	/* register crypto algorithms the device supports */
 	for (i = 0; i < ARRAY_SIZE(driver_hash); i++) {
-		/* TODO: check if h/w supports alg */
 		struct caam_hash_alg *t_alg;
+		struct caam_hash_template *alg = driver_hash + i;
+
+		/* If MD size is not supported by device, skip registration */
+		if (alg->template_ahash.halg.digestsize > md_limit)
+			continue;
 
 		/* register hmac version */
-		t_alg = caam_hash_alloc(&driver_hash[i], true);
+		t_alg = caam_hash_alloc(alg, true);
 		if (IS_ERR(t_alg)) {
 			err = PTR_ERR(t_alg);
-			pr_warn("%s alg allocation failed\n",
-				driver_hash[i].driver_name);
+			pr_warn("%s alg allocation failed\n", alg->driver_name);
 			continue;
 		}
 
@@ -1935,11 +1958,10 @@ static int __init caam_algapi_hash_init(void)
 			list_add_tail(&t_alg->entry, &hash_list);
 
 		/* register unkeyed version */
-		t_alg = caam_hash_alloc(&driver_hash[i], false);
+		t_alg = caam_hash_alloc(alg, false);
 		if (IS_ERR(t_alg)) {
 			err = PTR_ERR(t_alg);
-			pr_warn("%s alg allocation failed\n",
-				driver_hash[i].driver_name);
+			pr_warn("%s alg allocation failed\n", alg->driver_name);
 			continue;
 		}
 

drivers/crypto/caam/caamrng.c

@@ -315,7 +315,7 @@ static int __init caam_rng_init(void)
 	struct device_node *dev_node;
 	struct platform_device *pdev;
 	struct device *ctrldev;
-	void *priv;
+	struct caam_drv_private *priv;
 	int err;
 
 	dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec-v4.0");
@@ -342,6 +342,10 @@ static int __init caam_rng_init(void)
 	if (!priv)
 		return -ENODEV;
 
+	/* Check for an instantiated RNG before registration */
+	if (!(rd_reg32(&priv->ctrl->perfmon.cha_num_ls) & CHA_ID_LS_RNG_MASK))
+		return -ENODEV;
+
 	dev = caam_jr_alloc();
 	if (IS_ERR(dev)) {
 		pr_err("Job Ring Device allocation for transform failed\n");

drivers/crypto/caam/regs.h

@@ -156,18 +156,28 @@ struct jr_outentry {
 #define CHA_NUM_MS_DECONUM_SHIFT	24
 #define CHA_NUM_MS_DECONUM_MASK	(0xfull << CHA_NUM_MS_DECONUM_SHIFT)
 
-/* CHA Version IDs */
+/*
+ * CHA version IDs / instantiation bitfields
+ * Defined for use with the cha_id fields in perfmon, but the same shift/mask
+ * selectors can be used to pull out the number of instantiated blocks within
+ * cha_num fields in perfmon because the locations are the same.
+ */
 #define CHA_ID_LS_AES_SHIFT	0
-#define CHA_ID_LS_AES_MASK		(0xfull << CHA_ID_LS_AES_SHIFT)
+#define CHA_ID_LS_AES_MASK	(0xfull << CHA_ID_LS_AES_SHIFT)
+#define CHA_ID_LS_AES_LP	(0x3ull << CHA_ID_LS_AES_SHIFT)
+#define CHA_ID_LS_AES_HP	(0x4ull << CHA_ID_LS_AES_SHIFT)
 
 #define CHA_ID_LS_DES_SHIFT	4
-#define CHA_ID_LS_DES_MASK		(0xfull << CHA_ID_LS_DES_SHIFT)
+#define CHA_ID_LS_DES_MASK	(0xfull << CHA_ID_LS_DES_SHIFT)
 
 #define CHA_ID_LS_ARC4_SHIFT	8
 #define CHA_ID_LS_ARC4_MASK	(0xfull << CHA_ID_LS_ARC4_SHIFT)
 
 #define CHA_ID_LS_MD_SHIFT	12
 #define CHA_ID_LS_MD_MASK	(0xfull << CHA_ID_LS_MD_SHIFT)
+#define CHA_ID_LS_MD_LP256	(0x0ull << CHA_ID_LS_MD_SHIFT)
+#define CHA_ID_LS_MD_LP512	(0x1ull << CHA_ID_LS_MD_SHIFT)
+#define CHA_ID_LS_MD_HP		(0x2ull << CHA_ID_LS_MD_SHIFT)
 
 #define CHA_ID_LS_RNG_SHIFT	16
 #define CHA_ID_LS_RNG_MASK	(0xfull << CHA_ID_LS_RNG_SHIFT)