Commit 4a07eab3 authored by Corentin Labbe's avatar Corentin Labbe Committed by Herbert Xu
Browse files

crypto: sun8i-ce - Add support for the TRNG 



This patch had support for the TRNG present in the CE.
Note that according to the algorithm ID, 2 version of the TRNG exists,
the first present in H3/H5/R40/A64 and the second present in H6.
This patch adds support for both, but only the second is working
reliabily according to rngtest.

Signed-off-by: default avatarCorentin Labbe <clabbe@baylibre.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 5eb7e946

drivers/crypto/allwinner/Kconfig

+8 −0
Original line number Diff line number Diff line
@@ -77,6 +77,14 @@ config CRYPTO_DEV_SUN8I_CE_PRNG 
	  Select this option if you want to provide kernel-side support for

	  the Pseudo-Random Number Generator found in the Crypto Engine.



config CRYPTO_DEV_SUN8I_CE_TRNG

	bool "Support for Allwinner Crypto Engine TRNG"

	depends on CRYPTO_DEV_SUN8I_CE

	select HW_RANDOM

	help

	  Select this option if you want to provide kernel-side support for

	  the True Random Number Generator found in the Crypto Engine.



config CRYPTO_DEV_SUN8I_SS

	tristate "Support for Allwinner Security System cryptographic offloader"

	select CRYPTO_SKCIPHER

drivers/crypto/allwinner/sun8i-ce/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -2,3 +2,4 @@ obj-$(CONFIG_CRYPTO_DEV_SUN8I_CE) += sun8i-ce.o 
sun8i-ce-y += sun8i-ce-core.o sun8i-ce-cipher.o

sun8i-ce-$(CONFIG_CRYPTO_DEV_SUN8I_CE_HASH) += sun8i-ce-hash.o

sun8i-ce-$(CONFIG_CRYPTO_DEV_SUN8I_CE_PRNG) += sun8i-ce-prng.o

sun8i-ce-$(CONFIG_CRYPTO_DEV_SUN8I_CE_TRNG) += sun8i-ce-trng.o

drivers/crypto/allwinner/sun8i-ce/sun8i-ce-core.c

+18 −0
Original line number Diff line number Diff line
@@ -47,6 +47,7 @@ static const struct ce_variant ce_h3_variant = { 
		},

	.esr = ESR_H3,

	.prng = CE_ALG_PRNG,

	.trng = CE_ID_NOTSUPP,

};



static const struct ce_variant ce_h5_variant = {
@@ -63,6 +64,7 @@ static const struct ce_variant ce_h5_variant = { 
		},

	.esr = ESR_H5,

	.prng = CE_ALG_PRNG,

	.trng = CE_ID_NOTSUPP,

};



static const struct ce_variant ce_h6_variant = {
@@ -76,6 +78,7 @@ static const struct ce_variant ce_h6_variant = { 
	.cipher_t_dlen_in_bytes = true,

	.hash_t_dlen_in_bits = true,

	.prng_t_dlen_in_bytes = true,

	.trng_t_dlen_in_bytes = true,

	.ce_clks = {

		{ "bus", 0, 200000000 },

		{ "mod", 300000000, 0 },
@@ -83,6 +86,7 @@ static const struct ce_variant ce_h6_variant = { 
		},

	.esr = ESR_H6,

	.prng = CE_ALG_PRNG_V2,

	.trng = CE_ALG_TRNG_V2,

};



static const struct ce_variant ce_a64_variant = {
@@ -99,6 +103,7 @@ static const struct ce_variant ce_a64_variant = { 
		},

	.esr = ESR_A64,

	.prng = CE_ALG_PRNG,

	.trng = CE_ID_NOTSUPP,

};



static const struct ce_variant ce_r40_variant = {
@@ -115,6 +120,7 @@ static const struct ce_variant ce_r40_variant = { 
		},

	.esr = ESR_R40,

	.prng = CE_ALG_PRNG,

	.trng = CE_ID_NOTSUPP,

};



/*
@@ -589,6 +595,10 @@ static int sun8i_ce_debugfs_show(struct seq_file *seq, void *v) 
			break;

		}

	}

#ifdef CONFIG_CRYPTO_DEV_SUN8I_CE_TRNG

	seq_printf(seq, "HWRNG %lu %lu\n",

		   ce->hwrng_stat_req, ce->hwrng_stat_bytes);

#endif

	return 0;

}
@@ -925,6 +935,10 @@ static int sun8i_ce_probe(struct platform_device *pdev) 
	if (err < 0)

		goto error_alg;



#ifdef CONFIG_CRYPTO_DEV_SUN8I_CE_TRNG

	sun8i_ce_hwrng_register(ce);

#endif



	v = readl(ce->base + CE_CTR);

	v >>= CE_DIE_ID_SHIFT;

	v &= CE_DIE_ID_MASK;
@@ -954,6 +968,10 @@ static int sun8i_ce_remove(struct platform_device *pdev) 
{

	struct sun8i_ce_dev *ce = platform_get_drvdata(pdev);



#ifdef CONFIG_CRYPTO_DEV_SUN8I_CE_TRNG

	sun8i_ce_hwrng_unregister(ce);

#endif



	sun8i_ce_unregister_algs(ce);



#ifdef CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG

drivers/crypto/allwinner/sun8i-ce/sun8i-ce-trng.c

0 → 100644
+127 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * sun8i-ce-trng.c - hardware cryptographic offloader for

 * Allwinner H3/A64/H5/H2+/H6/R40 SoC

 *

 * Copyright (C) 2015-2020 Corentin Labbe <clabbe@baylibre.com>

 *

 * This file handle the TRNG

 *

 * You could find a link for the datasheet in Documentation/arm/sunxi/README

 */

#include "sun8i-ce.h"

#include <linux/dma-mapping.h>

#include <linux/pm_runtime.h>

#include <linux/hw_random.h>

/*

 * Note that according to the algorithm ID, 2 versions of the TRNG exists,

 * The first present in H3/H5/R40/A64 and the second present in H6.

 * This file adds support for both, but only the second is working

 * reliabily according to rngtest.

 **/



static int sun8i_ce_trng_read(struct hwrng *rng, void *data, size_t max, bool wait)

{

	struct sun8i_ce_dev *ce;

	dma_addr_t dma_dst;

	int err = 0;

	int flow = 3;

	unsigned int todo;

	struct sun8i_ce_flow *chan;

	struct ce_task *cet;

	u32 common;

	void *d;



	ce = container_of(rng, struct sun8i_ce_dev, trng);



	/* round the data length to a multiple of 32*/

	todo = max + 32;

	todo -= todo % 32;



	d = kzalloc(todo, GFP_KERNEL | GFP_DMA);

	if (!d)

		return -ENOMEM;



#ifdef CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG

	ce->hwrng_stat_req++;

	ce->hwrng_stat_bytes += todo;

#endif



	dma_dst = dma_map_single(ce->dev, d, todo, DMA_FROM_DEVICE);

	if (dma_mapping_error(ce->dev, dma_dst)) {

		dev_err(ce->dev, "Cannot DMA MAP DST\n");

		err = -EFAULT;

		goto err_dst;

	}



	err = pm_runtime_get_sync(ce->dev);

	if (err < 0) {

		pm_runtime_put_noidle(ce->dev);

		goto err_pm;

	}



	mutex_lock(&ce->rnglock);

	chan = &ce->chanlist[flow];



	cet = &chan->tl[0];

	memset(cet, 0, sizeof(struct ce_task));



	cet->t_id = cpu_to_le32(flow);

	common = ce->variant->trng | CE_COMM_INT;

	cet->t_common_ctl = cpu_to_le32(common);



	/* recent CE (H6) need length in bytes, in word otherwise */

	if (ce->variant->trng_t_dlen_in_bytes)

		cet->t_dlen = cpu_to_le32(todo);

	else

		cet->t_dlen = cpu_to_le32(todo / 4);



	cet->t_sym_ctl = 0;

	cet->t_asym_ctl = 0;



	cet->t_dst[0].addr = cpu_to_le32(dma_dst);

	cet->t_dst[0].len = cpu_to_le32(todo / 4);

	ce->chanlist[flow].timeout = todo;



	err = sun8i_ce_run_task(ce, 3, "TRNG");

	mutex_unlock(&ce->rnglock);



	pm_runtime_put(ce->dev);



err_pm:

	dma_unmap_single(ce->dev, dma_dst, todo, DMA_FROM_DEVICE);



	if (!err) {

		memcpy(data, d, max);

		err = max;

	}

	memzero_explicit(d, todo);

err_dst:

	kfree(d);

	return err;

}



int sun8i_ce_hwrng_register(struct sun8i_ce_dev *ce)

{

	int ret;



	if (ce->variant->trng == CE_ID_NOTSUPP) {

		dev_info(ce->dev, "TRNG not supported\n");

		return 0;

	}

	ce->trng.name = "sun8i Crypto Engine TRNG";

	ce->trng.read = sun8i_ce_trng_read;

	ce->trng.quality = 1000;



	ret = hwrng_register(&ce->trng);

	if (ret)

		dev_err(ce->dev, "Fail to register the TRNG\n");

	return ret;

}



void sun8i_ce_hwrng_unregister(struct sun8i_ce_dev *ce)

{

	if (ce->variant->trng == CE_ID_NOTSUPP)

		return;

	hwrng_unregister(&ce->trng);

}

drivers/crypto/allwinner/sun8i-ce/sun8i-ce.h

+18 −0
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#include <linux/atomic.h>

#include <linux/debugfs.h>

#include <linux/crypto.h>

#include <linux/hw_random.h>

#include <crypto/internal/hash.h>

#include <crypto/md5.h>

#include <crypto/rng.h>
@@ -55,7 +56,9 @@ 
#define CE_ALG_SHA256           19

#define CE_ALG_SHA384           20

#define CE_ALG_SHA512           21

#define CE_ALG_TRNG		48

#define CE_ALG_PRNG		49

#define CE_ALG_TRNG_V2		0x1c

#define CE_ALG_PRNG_V2		0x1d



/* Used in ce_variant */
@@ -129,9 +132,12 @@ struct ce_clock { 
 *				bits or words

 * @prng_t_dlen_in_bytes:	Does the request size for PRNG is in

 *				bytes or words

 * @trng_t_dlen_in_bytes:	Does the request size for TRNG is in

 *				bytes or words

 * @ce_clks:	list of clocks needed by this variant

 * @esr:	The type of error register

 * @prng:	The CE_ALG_XXX value for the PRNG

 * @trng:	The CE_ALG_XXX value for the TRNG

 */

struct ce_variant {

	char alg_cipher[CE_ID_CIPHER_MAX];
@@ -140,9 +146,11 @@ struct ce_variant { 
	bool cipher_t_dlen_in_bytes;

	bool hash_t_dlen_in_bits;

	bool prng_t_dlen_in_bytes;

	bool trng_t_dlen_in_bytes;

	struct ce_clock ce_clks[CE_MAX_CLOCKS];

	int esr;

	unsigned char prng;

	unsigned char trng;

};



struct sginfo {
@@ -218,6 +226,13 @@ struct sun8i_ce_dev { 
	struct dentry *dbgfs_dir;

	struct dentry *dbgfs_stats;

#endif

#ifdef CONFIG_CRYPTO_DEV_SUN8I_CE_TRNG

	struct hwrng trng;

#ifdef CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG

	unsigned long hwrng_stat_req;

	unsigned long hwrng_stat_bytes;

#endif

#endif

};



/*
@@ -355,3 +370,6 @@ int sun8i_ce_prng_generate(struct crypto_rng *tfm, const u8 *src, 
int sun8i_ce_prng_seed(struct crypto_rng *tfm, const u8 *seed, unsigned int slen);

void sun8i_ce_prng_exit(struct crypto_tfm *tfm);

int sun8i_ce_prng_init(struct crypto_tfm *tfm);



int sun8i_ce_hwrng_register(struct sun8i_ce_dev *ce);

void sun8i_ce_hwrng_unregister(struct sun8i_ce_dev *ce);

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