1 files changed, 280 insertions, 0 deletions
diff --git a/drivers/staging/ccree/cc_ivgen.c b/drivers/staging/ccree/cc_ivgen.c
new file mode 100644
index 000000000000..c47f419b277b
--- /dev/null
+++ b/drivers/staging/ccree/cc_ivgen.c
@@ -0,0 +1,280 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2012-2018 ARM Limited or its affiliates. */
+
+#include <crypto/ctr.h>
+#include "cc_driver.h"
+#include "cc_ivgen.h"
+#include "cc_request_mgr.h"
+#include "cc_sram_mgr.h"
+#include "cc_buffer_mgr.h"
+
+/* The max. size of pool *MUST* be <= SRAM total size */
+#define CC_IVPOOL_SIZE 1024
+/* The first 32B fraction of pool are dedicated to the
+ * next encryption "key" & "IV" for pool regeneration
+ */
+#define CC_IVPOOL_META_SIZE (CC_AES_IV_SIZE + AES_KEYSIZE_128)
+#define CC_IVPOOL_GEN_SEQ_LEN	4
+
+/**
+ * struct cc_ivgen_ctx -IV pool generation context
+ * @pool:          the start address of the iv-pool resides in internal RAM
+ * @ctr_key_dma:   address of pool's encryption key material in internal RAM
+ * @ctr_iv_dma:    address of pool's counter iv in internal RAM
+ * @next_iv_ofs:   the offset to the next available IV in pool
+ * @pool_meta:     virt. address of the initial enc. key/IV
+ * @pool_meta_dma: phys. address of the initial enc. key/IV
+ */
+struct cc_ivgen_ctx {
+	cc_sram_addr_t pool;
+	cc_sram_addr_t ctr_key;
+	cc_sram_addr_t ctr_iv;
+	u32 next_iv_ofs;
+	u8 *pool_meta;
+	dma_addr_t pool_meta_dma;
+};
+
+/*!
+ * Generates CC_IVPOOL_SIZE of random bytes by
+ * encrypting 0's using AES128-CTR.
+ *
+ * \param ivgen iv-pool context
+ * \param iv_seq IN/OUT array to the descriptors sequence
+ * \param iv_seq_len IN/OUT pointer to the sequence length
+ */
+static int cc_gen_iv_pool(struct cc_ivgen_ctx *ivgen_ctx,
+			  struct cc_hw_desc iv_seq[], unsigned int *iv_seq_len)
+{
+	unsigned int idx = *iv_seq_len;
+
+	if ((*iv_seq_len + CC_IVPOOL_GEN_SEQ_LEN) > CC_IVPOOL_SEQ_LEN) {
+		/* The sequence will be longer than allowed */
+		return -EINVAL;
+	}
+	/* Setup key */
+	hw_desc_init(&iv_seq[idx]);
+	set_din_sram(&iv_seq[idx], ivgen_ctx->ctr_key, AES_KEYSIZE_128);
+	set_setup_mode(&iv_seq[idx], SETUP_LOAD_KEY0);
+	set_cipher_config0(&iv_seq[idx], DESC_DIRECTION_ENCRYPT_ENCRYPT);
+	set_flow_mode(&iv_seq[idx], S_DIN_to_AES);
+	set_key_size_aes(&iv_seq[idx], CC_AES_128_BIT_KEY_SIZE);
+	set_cipher_mode(&iv_seq[idx], DRV_CIPHER_CTR);
+	idx++;
+
+	/* Setup cipher state */
+	hw_desc_init(&iv_seq[idx]);
+	set_din_sram(&iv_seq[idx], ivgen_ctx->ctr_iv, CC_AES_IV_SIZE);
+	set_cipher_config0(&iv_seq[idx], DESC_DIRECTION_ENCRYPT_ENCRYPT);
+	set_flow_mode(&iv_seq[idx], S_DIN_to_AES);
+	set_setup_mode(&iv_seq[idx], SETUP_LOAD_STATE1);
+	set_key_size_aes(&iv_seq[idx], CC_AES_128_BIT_KEY_SIZE);
+	set_cipher_mode(&iv_seq[idx], DRV_CIPHER_CTR);
+	idx++;
+
+	/* Perform dummy encrypt to skip first block */
+	hw_desc_init(&iv_seq[idx]);
+	set_din_const(&iv_seq[idx], 0, CC_AES_IV_SIZE);
+	set_dout_sram(&iv_seq[idx], ivgen_ctx->pool, CC_AES_IV_SIZE);
+	set_flow_mode(&iv_seq[idx], DIN_AES_DOUT);
+	idx++;
+
+	/* Generate IV pool */
+	hw_desc_init(&iv_seq[idx]);
+	set_din_const(&iv_seq[idx], 0, CC_IVPOOL_SIZE);
+	set_dout_sram(&iv_seq[idx], ivgen_ctx->pool, CC_IVPOOL_SIZE);
+	set_flow_mode(&iv_seq[idx], DIN_AES_DOUT);
+	idx++;
+
+	*iv_seq_len = idx; /* Update sequence length */
+
+	/* queue ordering assures pool readiness */
+	ivgen_ctx->next_iv_ofs = CC_IVPOOL_META_SIZE;
+
+	return 0;
+}
+
+/*!
+ * Generates the initial pool in SRAM.
+ * This function should be invoked when resuming DX driver.
+ *
+ * \param drvdata
+ *
+ * \return int Zero for success, negative value otherwise.
+ */
+int cc_init_iv_sram(struct cc_drvdata *drvdata)
+{
+	struct cc_ivgen_ctx *ivgen_ctx = drvdata->ivgen_handle;
+	struct cc_hw_desc iv_seq[CC_IVPOOL_SEQ_LEN];
+	unsigned int iv_seq_len = 0;
+	int rc;
+
+	/* Generate initial enc. key/iv */
+	get_random_bytes(ivgen_ctx->pool_meta, CC_IVPOOL_META_SIZE);
+
+	/* The first 32B reserved for the enc. Key/IV */
+	ivgen_ctx->ctr_key = ivgen_ctx->pool;
+	ivgen_ctx->ctr_iv = ivgen_ctx->pool + AES_KEYSIZE_128;
+
+	/* Copy initial enc. key and IV to SRAM at a single descriptor */
+	hw_desc_init(&iv_seq[iv_seq_len]);
+	set_din_type(&iv_seq[iv_seq_len], DMA_DLLI, ivgen_ctx->pool_meta_dma,
+		     CC_IVPOOL_META_SIZE, NS_BIT);
+	set_dout_sram(&iv_seq[iv_seq_len], ivgen_ctx->pool,
+		      CC_IVPOOL_META_SIZE);
+	set_flow_mode(&iv_seq[iv_seq_len], BYPASS);
+	iv_seq_len++;
+
+	/* Generate initial pool */
+	rc = cc_gen_iv_pool(ivgen_ctx, iv_seq, &iv_seq_len);
+	if (rc)
+		return rc;
+
+	/* Fire-and-forget */
+	return send_request_init(drvdata, iv_seq, iv_seq_len);
+}
+
+/*!
+ * Free iv-pool and ivgen context.
+ *
+ * \param drvdata
+ */
+void cc_ivgen_fini(struct cc_drvdata *drvdata)
+{
+	struct cc_ivgen_ctx *ivgen_ctx = drvdata->ivgen_handle;
+	struct device *device = &drvdata->plat_dev->dev;
+
+	if (!ivgen_ctx)
+		return;
+
+	if (ivgen_ctx->pool_meta) {
+		memset(ivgen_ctx->pool_meta, 0, CC_IVPOOL_META_SIZE);
+		dma_free_coherent(device, CC_IVPOOL_META_SIZE,
+				  ivgen_ctx->pool_meta,
+				  ivgen_ctx->pool_meta_dma);
+	}
+
+	ivgen_ctx->pool = NULL_SRAM_ADDR;
+
+	/* release "this" context */
+	kfree(ivgen_ctx);
+}
+
+/*!
+ * Allocates iv-pool and maps resources.
+ * This function generates the first IV pool.
+ *
+ * \param drvdata Driver's private context
+ *
+ * \return int Zero for success, negative value otherwise.
+ */
+int cc_ivgen_init(struct cc_drvdata *drvdata)
+{
+	struct cc_ivgen_ctx *ivgen_ctx;
+	struct device *device = &drvdata->plat_dev->dev;
+	int rc;
+
+	/* Allocate "this" context */
+	ivgen_ctx = kzalloc(sizeof(*ivgen_ctx), GFP_KERNEL);
+	if (!ivgen_ctx)
+		return -ENOMEM;
+
+	drvdata->ivgen_handle = ivgen_ctx;
+
+	/* Allocate pool's header for initial enc. key/IV */
+	ivgen_ctx->pool_meta = dma_alloc_coherent(device, CC_IVPOOL_META_SIZE,
+						  &ivgen_ctx->pool_meta_dma,
+						  GFP_KERNEL);
+	if (!ivgen_ctx->pool_meta) {
+		dev_err(device, "Not enough memory to allocate DMA of pool_meta (%u B)\n",
+			CC_IVPOOL_META_SIZE);
+		rc = -ENOMEM;
+		goto out;
+	}
+	/* Allocate IV pool in SRAM */
+	ivgen_ctx->pool = cc_sram_alloc(drvdata, CC_IVPOOL_SIZE);
+	if (ivgen_ctx->pool == NULL_SRAM_ADDR) {
+		dev_err(device, "SRAM pool exhausted\n");
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	return cc_init_iv_sram(drvdata);
+
+out:
+	cc_ivgen_fini(drvdata);
+	return rc;
+}
+
+/*!
+ * Acquires 16 Bytes IV from the iv-pool
+ *
+ * \param drvdata Driver private context
+ * \param iv_out_dma Array of physical IV out addresses
+ * \param iv_out_dma_len Length of iv_out_dma array (additional elements
+ *                       of iv_out_dma array are ignore)
+ * \param iv_out_size May be 8 or 16 bytes long
+ * \param iv_seq IN/OUT array to the descriptors sequence
+ * \param iv_seq_len IN/OUT pointer to the sequence length
+ *
+ * \return int Zero for success, negative value otherwise.
+ */
+int cc_get_iv(struct cc_drvdata *drvdata, dma_addr_t iv_out_dma[],
+	      unsigned int iv_out_dma_len, unsigned int iv_out_size,
+	      struct cc_hw_desc iv_seq[], unsigned int *iv_seq_len)
+{
+	struct cc_ivgen_ctx *ivgen_ctx = drvdata->ivgen_handle;
+	unsigned int idx = *iv_seq_len;
+	struct device *dev = drvdata_to_dev(drvdata);
+	unsigned int t;
+
+	if (iv_out_size != CC_AES_IV_SIZE &&
+	    iv_out_size != CTR_RFC3686_IV_SIZE) {
+		return -EINVAL;
+	}
+	if ((iv_out_dma_len + 1) > CC_IVPOOL_SEQ_LEN) {
+		/* The sequence will be longer than allowed */
+		return -EINVAL;
+	}
+
+	/* check that number of generated IV is limited to max dma address
+	 * iv buffer size
+	 */
+	if (iv_out_dma_len > CC_MAX_IVGEN_DMA_ADDRESSES) {
+		/* The sequence will be longer than allowed */
+		return -EINVAL;
+	}
+
+	for (t = 0; t < iv_out_dma_len; t++) {
+		/* Acquire IV from pool */
+		hw_desc_init(&iv_seq[idx]);
+		set_din_sram(&iv_seq[idx], (ivgen_ctx->pool +
+					    ivgen_ctx->next_iv_ofs),
+			     iv_out_size);
+		set_dout_dlli(&iv_seq[idx], iv_out_dma[t], iv_out_size,
+			      NS_BIT, 0);
+		set_flow_mode(&iv_seq[idx], BYPASS);
+		idx++;
+	}
+
+	/* Bypass operation is proceeded by crypto sequence, hence must
+	 *  assure bypass-write-transaction by a memory barrier
+	 */
+	hw_desc_init(&iv_seq[idx]);
+	set_din_no_dma(&iv_seq[idx], 0, 0xfffff0);
+	set_dout_no_dma(&iv_seq[idx], 0, 0, 1);
+	idx++;
+
+	*iv_seq_len = idx; /* update seq length */
+
+	/* Update iv index */
+	ivgen_ctx->next_iv_ofs += iv_out_size;
+
+	if ((CC_IVPOOL_SIZE - ivgen_ctx->next_iv_ofs) < CC_AES_IV_SIZE) {
+		dev_dbg(dev, "Pool exhausted, regenerating iv-pool\n");
+		/* pool is drained -regenerate it! */
+		return cc_gen_iv_pool(ivgen_ctx, iv_seq, iv_seq_len);
+	}
+
+	return 0;
+}
+