1 // SPDX-License-Identifier: GPL-2.0
3 * sun8i-ce-prng.c - hardware cryptographic offloader for
4 * Allwinner H3/A64/H5/H2+/H6/R40 SoC
6 * Copyright (C) 2015-2020 Corentin Labbe <clabbe@baylibre.com>
8 * This file handle the PRNG
10 * You could find a link for the datasheet in Documentation/arm/sunxi.rst
13 #include <linux/dma-mapping.h>
14 #include <linux/pm_runtime.h>
15 #include <crypto/internal/rng.h>
17 int sun8i_ce_prng_init(struct crypto_tfm *tfm)
19 struct sun8i_ce_rng_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
21 memset(ctx, 0, sizeof(struct sun8i_ce_rng_tfm_ctx));
25 void sun8i_ce_prng_exit(struct crypto_tfm *tfm)
27 struct sun8i_ce_rng_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
29 memzero_explicit(ctx->seed, ctx->slen);
35 int sun8i_ce_prng_seed(struct crypto_rng *tfm, const u8 *seed,
38 struct sun8i_ce_rng_tfm_ctx *ctx = crypto_rng_ctx(tfm);
40 if (ctx->seed && ctx->slen != slen) {
41 memzero_explicit(ctx->seed, ctx->slen);
47 ctx->seed = kmalloc(slen, GFP_KERNEL | GFP_DMA);
51 memcpy(ctx->seed, seed, slen);
57 int sun8i_ce_prng_generate(struct crypto_rng *tfm, const u8 *src,
58 unsigned int slen, u8 *dst, unsigned int dlen)
60 struct sun8i_ce_rng_tfm_ctx *ctx = crypto_rng_ctx(tfm);
61 struct rng_alg *alg = crypto_rng_alg(tfm);
62 struct sun8i_ce_alg_template *algt;
63 struct sun8i_ce_dev *ce;
64 dma_addr_t dma_iv, dma_dst;
68 struct sun8i_ce_flow *chan;
73 algt = container_of(alg, struct sun8i_ce_alg_template, alg.rng);
77 dev_err(ce->dev, "not seeded\n");
81 /* we want dlen + seedsize rounded up to a multiple of PRNG_DATA_SIZE */
82 todo = dlen + ctx->slen + PRNG_DATA_SIZE * 2;
83 todo -= todo % PRNG_DATA_SIZE;
85 d = kzalloc(todo, GFP_KERNEL | GFP_DMA);
91 dev_dbg(ce->dev, "%s PRNG slen=%u dlen=%u todo=%u multi=%u\n", __func__,
92 slen, dlen, todo, todo / PRNG_DATA_SIZE);
94 #ifdef CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG
96 algt->stat_bytes += todo;
99 dma_iv = dma_map_single(ce->dev, ctx->seed, ctx->slen, DMA_TO_DEVICE);
100 if (dma_mapping_error(ce->dev, dma_iv)) {
101 dev_err(ce->dev, "Cannot DMA MAP IV\n");
105 dma_dst = dma_map_single(ce->dev, d, todo, DMA_FROM_DEVICE);
106 if (dma_mapping_error(ce->dev, dma_dst)) {
107 dev_err(ce->dev, "Cannot DMA MAP DST\n");
112 err = pm_runtime_get_sync(ce->dev);
114 pm_runtime_put_noidle(ce->dev);
118 mutex_lock(&ce->rnglock);
119 chan = &ce->chanlist[flow];
122 memset(cet, 0, sizeof(struct ce_task));
124 cet->t_id = cpu_to_le32(flow);
125 common = ce->variant->prng | CE_COMM_INT;
126 cet->t_common_ctl = cpu_to_le32(common);
128 /* recent CE (H6) need length in bytes, in word otherwise */
129 if (ce->variant->prng_t_dlen_in_bytes)
130 cet->t_dlen = cpu_to_le32(todo);
132 cet->t_dlen = cpu_to_le32(todo / 4);
135 cet->t_sym_ctl = cpu_to_le32(sym);
138 cet->t_key = cpu_to_le32(dma_iv);
139 cet->t_iv = cpu_to_le32(dma_iv);
141 cet->t_dst[0].addr = cpu_to_le32(dma_dst);
142 cet->t_dst[0].len = cpu_to_le32(todo / 4);
143 ce->chanlist[flow].timeout = 2000;
145 err = sun8i_ce_run_task(ce, 3, "PRNG");
146 mutex_unlock(&ce->rnglock);
148 pm_runtime_put(ce->dev);
151 dma_unmap_single(ce->dev, dma_dst, todo, DMA_FROM_DEVICE);
153 dma_unmap_single(ce->dev, dma_iv, ctx->slen, DMA_TO_DEVICE);
156 memcpy(dst, d, dlen);
157 memcpy(ctx->seed, d + dlen, ctx->slen);
159 memzero_explicit(d, todo);