1 files changed, 382 insertions, 0 deletions
diff --git a/drivers/crypto/amlogic/amlogic-gxl-cipher.c b/drivers/crypto/amlogic/amlogic-gxl-cipher.c
new file mode 100644
index 000000000000..e589015aac1c
--- /dev/null
+++ b/drivers/crypto/amlogic/amlogic-gxl-cipher.c
@@ -0,0 +1,382 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * amlogic-cipher.c - hardware cryptographic offloader for Amlogic GXL SoC
+ *
+ * Copyright (C) 2018-2019 Corentin LABBE <clabbe@baylibre.com>
+ *
+ * This file add support for AES cipher with 128,192,256 bits keysize in
+ * CBC and ECB mode.
+ */
+
+#include <linux/crypto.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <crypto/scatterwalk.h>
+#include <linux/scatterlist.h>
+#include <linux/dma-mapping.h>
+#include <crypto/internal/skcipher.h>
+#include "amlogic-gxl.h"
+
+static int get_engine_number(struct meson_dev *mc)
+{
+	return atomic_inc_return(&mc->flow) % MAXFLOW;
+}
+
+static bool meson_cipher_need_fallback(struct skcipher_request *areq)
+{
+	struct scatterlist *src_sg = areq->src;
+	struct scatterlist *dst_sg = areq->dst;
+
+	if (areq->cryptlen == 0)
+		return true;
+
+	if (sg_nents(src_sg) != sg_nents(dst_sg))
+		return true;
+
+	/* KEY/IV descriptors use 3 desc */
+	if (sg_nents(src_sg) > MAXDESC - 3 || sg_nents(dst_sg) > MAXDESC - 3)
+		return true;
+
+	while (src_sg && dst_sg) {
+		if ((src_sg->length % 16) != 0)
+			return true;
+		if ((dst_sg->length % 16) != 0)
+			return true;
+		if (src_sg->length != dst_sg->length)
+			return true;
+		if (!IS_ALIGNED(src_sg->offset, sizeof(u32)))
+			return true;
+		if (!IS_ALIGNED(dst_sg->offset, sizeof(u32)))
+			return true;
+		src_sg = sg_next(src_sg);
+		dst_sg = sg_next(dst_sg);
+	}
+
+	return false;
+}
+
+static int meson_cipher_do_fallback(struct skcipher_request *areq)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
+	struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
+	struct meson_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
+	int err;
+#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
+	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
+	struct meson_alg_template *algt;
+#endif
+	SYNC_SKCIPHER_REQUEST_ON_STACK(req, op->fallback_tfm);
+
+#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
+	algt = container_of(alg, struct meson_alg_template, alg.skcipher);
+	algt->stat_fb++;
+#endif
+	skcipher_request_set_sync_tfm(req, op->fallback_tfm);
+	skcipher_request_set_callback(req, areq->base.flags, NULL, NULL);
+	skcipher_request_set_crypt(req, areq->src, areq->dst,
+				   areq->cryptlen, areq->iv);
+	if (rctx->op_dir == MESON_DECRYPT)
+		err = crypto_skcipher_decrypt(req);
+	else
+		err = crypto_skcipher_encrypt(req);
+	skcipher_request_zero(req);
+	return err;
+}
+
+static int meson_cipher(struct skcipher_request *areq)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
+	struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
+	struct meson_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
+	struct meson_dev *mc = op->mc;
+	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
+	struct meson_alg_template *algt;
+	int flow = rctx->flow;
+	unsigned int todo, eat, len;
+	struct scatterlist *src_sg = areq->src;
+	struct scatterlist *dst_sg = areq->dst;
+	struct meson_desc *desc;
+	int nr_sgs, nr_sgd;
+	int i, err = 0;
+	unsigned int keyivlen, ivsize, offset, tloffset;
+	dma_addr_t phykeyiv;
+	void *backup_iv = NULL, *bkeyiv;
+	__le32 v;
+
+	algt = container_of(alg, struct meson_alg_template, alg.skcipher);
+
+	dev_dbg(mc->dev, "%s %s %u %x IV(%u) key=%u flow=%d\n", __func__,
+		crypto_tfm_alg_name(areq->base.tfm),
+		areq->cryptlen,
+		rctx->op_dir, crypto_skcipher_ivsize(tfm),
+		op->keylen, flow);
+
+#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
+	algt->stat_req++;
+	mc->chanlist[flow].stat_req++;
+#endif
+
+	/*
+	 * The hardware expect a list of meson_desc structures.
+	 * The 2 first structures store key
+	 * The third stores IV
+	 */
+	bkeyiv = kzalloc(48, GFP_KERNEL | GFP_DMA);
+	if (!bkeyiv)
+		return -ENOMEM;
+
+	memcpy(bkeyiv, op->key, op->keylen);
+	keyivlen = op->keylen;
+
+	ivsize = crypto_skcipher_ivsize(tfm);
+	if (areq->iv && ivsize > 0) {
+		if (ivsize > areq->cryptlen) {
+			dev_err(mc->dev, "invalid ivsize=%d vs len=%d\n", ivsize, areq->cryptlen);
+			err = -EINVAL;
+			goto theend;
+		}
+		memcpy(bkeyiv + 32, areq->iv, ivsize);
+		keyivlen = 48;
+		if (rctx->op_dir == MESON_DECRYPT) {
+			backup_iv = kzalloc(ivsize, GFP_KERNEL);
+			if (!backup_iv) {
+				err = -ENOMEM;
+				goto theend;
+			}
+			offset = areq->cryptlen - ivsize;
+			scatterwalk_map_and_copy(backup_iv, areq->src, offset,
+						 ivsize, 0);
+		}
+	}
+	if (keyivlen == 24)
+		keyivlen = 32;
+
+	phykeyiv = dma_map_single(mc->dev, bkeyiv, keyivlen,
+				  DMA_TO_DEVICE);
+	err = dma_mapping_error(mc->dev, phykeyiv);
+	if (err) {
+		dev_err(mc->dev, "Cannot DMA MAP KEY IV\n");
+		goto theend;
+	}
+
+	tloffset = 0;
+	eat = 0;
+	i = 0;
+	while (keyivlen > eat) {
+		desc = &mc->chanlist[flow].tl[tloffset];
+		memset(desc, 0, sizeof(struct meson_desc));
+		todo = min(keyivlen - eat, 16u);
+		desc->t_src = cpu_to_le32(phykeyiv + i * 16);
+		desc->t_dst = cpu_to_le32(i * 16);
+		v = (MODE_KEY << 20) | DESC_OWN | 16;
+		desc->t_status = cpu_to_le32(v);
+
+		eat += todo;
+		i++;
+		tloffset++;
+	}
+
+	if (areq->src == areq->dst) {
+		nr_sgs = dma_map_sg(mc->dev, areq->src, sg_nents(areq->src),
+				    DMA_BIDIRECTIONAL);
+		if (nr_sgs < 0) {
+			dev_err(mc->dev, "Invalid SG count %d\n", nr_sgs);
+			err = -EINVAL;
+			goto theend;
+		}
+		nr_sgd = nr_sgs;
+	} else {
+		nr_sgs = dma_map_sg(mc->dev, areq->src, sg_nents(areq->src),
+				    DMA_TO_DEVICE);
+		if (nr_sgs < 0 || nr_sgs > MAXDESC - 3) {
+			dev_err(mc->dev, "Invalid SG count %d\n", nr_sgs);
+			err = -EINVAL;
+			goto theend;
+		}
+		nr_sgd = dma_map_sg(mc->dev, areq->dst, sg_nents(areq->dst),
+				    DMA_FROM_DEVICE);
+		if (nr_sgd < 0 || nr_sgd > MAXDESC - 3) {
+			dev_err(mc->dev, "Invalid SG count %d\n", nr_sgd);
+			err = -EINVAL;
+			goto theend;
+		}
+	}
+
+	src_sg = areq->src;
+	dst_sg = areq->dst;
+	len = areq->cryptlen;
+	while (src_sg) {
+		desc = &mc->chanlist[flow].tl[tloffset];
+		memset(desc, 0, sizeof(struct meson_desc));
+
+		desc->t_src = cpu_to_le32(sg_dma_address(src_sg));
+		desc->t_dst = cpu_to_le32(sg_dma_address(dst_sg));
+		todo = min(len, sg_dma_len(src_sg));
+		v = (op->keymode << 20) | DESC_OWN | todo | (algt->blockmode << 26);
+		if (rctx->op_dir)
+			v |= DESC_ENCRYPTION;
+		len -= todo;
+
+		if (!sg_next(src_sg))
+			v |= DESC_LAST;
+		desc->t_status = cpu_to_le32(v);
+		tloffset++;
+		src_sg = sg_next(src_sg);
+		dst_sg = sg_next(dst_sg);
+	}
+
+	reinit_completion(&mc->chanlist[flow].complete);
+	mc->chanlist[flow].status = 0;
+	writel(mc->chanlist[flow].t_phy | 2, mc->base + (flow << 2));
+	wait_for_completion_interruptible_timeout(&mc->chanlist[flow].complete,
+						  msecs_to_jiffies(500));
+	if (mc->chanlist[flow].status == 0) {
+		dev_err(mc->dev, "DMA timeout for flow %d\n", flow);
+		err = -EINVAL;
+	}
+
+	dma_unmap_single(mc->dev, phykeyiv, keyivlen, DMA_TO_DEVICE);
+
+	if (areq->src == areq->dst) {
+		dma_unmap_sg(mc->dev, areq->src, nr_sgs, DMA_BIDIRECTIONAL);
+	} else {
+		dma_unmap_sg(mc->dev, areq->src, nr_sgs, DMA_TO_DEVICE);
+		dma_unmap_sg(mc->dev, areq->dst, nr_sgd, DMA_FROM_DEVICE);
+	}
+
+	if (areq->iv && ivsize > 0) {
+		if (rctx->op_dir == MESON_DECRYPT) {
+			memcpy(areq->iv, backup_iv, ivsize);
+		} else {
+			scatterwalk_map_and_copy(areq->iv, areq->dst,
+						 areq->cryptlen - ivsize,
+						 ivsize, 0);
+		}
+	}
+theend:
+	kzfree(bkeyiv);
+	kzfree(backup_iv);
+
+	return err;
+}
+
+static int meson_handle_cipher_request(struct crypto_engine *engine,
+				       void *areq)
+{
+	int err;
+	struct skcipher_request *breq = container_of(areq, struct skcipher_request, base);
+
+	err = meson_cipher(breq);
+	crypto_finalize_skcipher_request(engine, breq, err);
+
+	return 0;
+}
+
+int meson_skdecrypt(struct skcipher_request *areq)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
+	struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
+	struct meson_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
+	struct crypto_engine *engine;
+	int e;
+
+	rctx->op_dir = MESON_DECRYPT;
+	if (meson_cipher_need_fallback(areq))
+		return meson_cipher_do_fallback(areq);
+	e = get_engine_number(op->mc);
+	engine = op->mc->chanlist[e].engine;
+	rctx->flow = e;
+
+	return crypto_transfer_skcipher_request_to_engine(engine, areq);
+}
+
+int meson_skencrypt(struct skcipher_request *areq)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
+	struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
+	struct meson_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
+	struct crypto_engine *engine;
+	int e;
+
+	rctx->op_dir = MESON_ENCRYPT;
+	if (meson_cipher_need_fallback(areq))
+		return meson_cipher_do_fallback(areq);
+	e = get_engine_number(op->mc);
+	engine = op->mc->chanlist[e].engine;
+	rctx->flow = e;
+
+	return crypto_transfer_skcipher_request_to_engine(engine, areq);
+}
+
+int meson_cipher_init(struct crypto_tfm *tfm)
+{
+	struct meson_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
+	struct meson_alg_template *algt;
+	const char *name = crypto_tfm_alg_name(tfm);
+	struct crypto_skcipher *sktfm = __crypto_skcipher_cast(tfm);
+	struct skcipher_alg *alg = crypto_skcipher_alg(sktfm);
+
+	memset(op, 0, sizeof(struct meson_cipher_tfm_ctx));
+
+	algt = container_of(alg, struct meson_alg_template, alg.skcipher);
+	op->mc = algt->mc;
+
+	sktfm->reqsize = sizeof(struct meson_cipher_req_ctx);
+
+	op->fallback_tfm = crypto_alloc_sync_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
+	if (IS_ERR(op->fallback_tfm)) {
+		dev_err(op->mc->dev, "ERROR: Cannot allocate fallback for %s %ld\n",
+			name, PTR_ERR(op->fallback_tfm));
+		return PTR_ERR(op->fallback_tfm);
+	}
+
+	op->enginectx.op.do_one_request = meson_handle_cipher_request;
+	op->enginectx.op.prepare_request = NULL;
+	op->enginectx.op.unprepare_request = NULL;
+
+	return 0;
+}
+
+void meson_cipher_exit(struct crypto_tfm *tfm)
+{
+	struct meson_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
+
+	if (op->key) {
+		memzero_explicit(op->key, op->keylen);
+		kfree(op->key);
+	}
+	crypto_free_sync_skcipher(op->fallback_tfm);
+}
+
+int meson_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
+		     unsigned int keylen)
+{
+	struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
+	struct meson_dev *mc = op->mc;
+
+	switch (keylen) {
+	case 128 / 8:
+		op->keymode = MODE_AES_128;
+		break;
+	case 192 / 8:
+		op->keymode = MODE_AES_192;
+		break;
+	case 256 / 8:
+		op->keymode = MODE_AES_256;
+		break;
+	default:
+		dev_dbg(mc->dev, "ERROR: Invalid keylen %u\n", keylen);
+		crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+		return -EINVAL;
+	}
+	if (op->key) {
+		memzero_explicit(op->key, op->keylen);
+		kfree(op->key);
+	}
+	op->keylen = keylen;
+	op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
+	if (!op->key)
+		return -ENOMEM;
+
+	return crypto_sync_skcipher_setkey(op->fallback_tfm, key, keylen);
+}