127 lines
2.9 KiB
C
127 lines
2.9 KiB
C
|
// 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.rst
|
||
|
|
*/
|
||
|
|
#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;
|
||
|
|
}
|
||
|
|
err_dst:
|
||
|
|
kfree_sensitive(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);
|
||
|
|
}
|