linux/drivers/crypto/mxs-dcp.c
Ard Biesheuvel c9598d4e13 crypto: mxs-dcp - permit asynchronous skcipher as fallback
Even though the mxs-dcp driver implements asynchronous versions of
ecb(aes) and cbc(aes), the fallbacks it allocates are required to be
synchronous. Given that SIMD based software implementations are usually
asynchronous as well, even though they rarely complete asynchronously
(this typically only happens in cases where the request was made from
softirq context, while SIMD was already in use in the task context that
it interrupted), these implementations are disregarded, and either the
generic C version or another table based version implemented in assembler
is selected instead.

Since falling back to synchronous AES is not only a performance issue, but
potentially a security issue as well (due to the fact that table based AES
is not time invariant), let's fix this, by allocating an ordinary skcipher
as the fallback, and invoke it with the completion routine that was given
to the outer request.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-07-16 21:49:03 +10:00

1183 lines
29 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Freescale i.MX23/i.MX28 Data Co-Processor driver
*
* Copyright (C) 2013 Marek Vasut <marex@denx.de>
*/
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/stmp_device.h>
#include <linux/clk.h>
#include <crypto/aes.h>
#include <crypto/sha.h>
#include <crypto/internal/hash.h>
#include <crypto/internal/skcipher.h>
#include <crypto/scatterwalk.h>
#define DCP_MAX_CHANS 4
#define DCP_BUF_SZ PAGE_SIZE
#define DCP_SHA_PAY_SZ 64
#define DCP_ALIGNMENT 64
/*
* Null hashes to align with hw behavior on imx6sl and ull
* these are flipped for consistency with hw output
*/
static const uint8_t sha1_null_hash[] =
"\x09\x07\xd8\xaf\x90\x18\x60\x95\xef\xbf"
"\x55\x32\x0d\x4b\x6b\x5e\xee\xa3\x39\xda";
static const uint8_t sha256_null_hash[] =
"\x55\xb8\x52\x78\x1b\x99\x95\xa4"
"\x4c\x93\x9b\x64\xe4\x41\xae\x27"
"\x24\xb9\x6f\x99\xc8\xf4\xfb\x9a"
"\x14\x1c\xfc\x98\x42\xc4\xb0\xe3";
/* DCP DMA descriptor. */
struct dcp_dma_desc {
uint32_t next_cmd_addr;
uint32_t control0;
uint32_t control1;
uint32_t source;
uint32_t destination;
uint32_t size;
uint32_t payload;
uint32_t status;
};
/* Coherent aligned block for bounce buffering. */
struct dcp_coherent_block {
uint8_t aes_in_buf[DCP_BUF_SZ];
uint8_t aes_out_buf[DCP_BUF_SZ];
uint8_t sha_in_buf[DCP_BUF_SZ];
uint8_t sha_out_buf[DCP_SHA_PAY_SZ];
uint8_t aes_key[2 * AES_KEYSIZE_128];
struct dcp_dma_desc desc[DCP_MAX_CHANS];
};
struct dcp {
struct device *dev;
void __iomem *base;
uint32_t caps;
struct dcp_coherent_block *coh;
struct completion completion[DCP_MAX_CHANS];
spinlock_t lock[DCP_MAX_CHANS];
struct task_struct *thread[DCP_MAX_CHANS];
struct crypto_queue queue[DCP_MAX_CHANS];
struct clk *dcp_clk;
};
enum dcp_chan {
DCP_CHAN_HASH_SHA = 0,
DCP_CHAN_CRYPTO = 2,
};
struct dcp_async_ctx {
/* Common context */
enum dcp_chan chan;
uint32_t fill;
/* SHA Hash-specific context */
struct mutex mutex;
uint32_t alg;
unsigned int hot:1;
/* Crypto-specific context */
struct crypto_skcipher *fallback;
unsigned int key_len;
uint8_t key[AES_KEYSIZE_128];
};
struct dcp_aes_req_ctx {
unsigned int enc:1;
unsigned int ecb:1;
struct skcipher_request fallback_req; // keep at the end
};
struct dcp_sha_req_ctx {
unsigned int init:1;
unsigned int fini:1;
};
struct dcp_export_state {
struct dcp_sha_req_ctx req_ctx;
struct dcp_async_ctx async_ctx;
};
/*
* There can even be only one instance of the MXS DCP due to the
* design of Linux Crypto API.
*/
static struct dcp *global_sdcp;
/* DCP register layout. */
#define MXS_DCP_CTRL 0x00
#define MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES (1 << 23)
#define MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING (1 << 22)
#define MXS_DCP_STAT 0x10
#define MXS_DCP_STAT_CLR 0x18
#define MXS_DCP_STAT_IRQ_MASK 0xf
#define MXS_DCP_CHANNELCTRL 0x20
#define MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK 0xff
#define MXS_DCP_CAPABILITY1 0x40
#define MXS_DCP_CAPABILITY1_SHA256 (4 << 16)
#define MXS_DCP_CAPABILITY1_SHA1 (1 << 16)
#define MXS_DCP_CAPABILITY1_AES128 (1 << 0)
#define MXS_DCP_CONTEXT 0x50
#define MXS_DCP_CH_N_CMDPTR(n) (0x100 + ((n) * 0x40))
#define MXS_DCP_CH_N_SEMA(n) (0x110 + ((n) * 0x40))
#define MXS_DCP_CH_N_STAT(n) (0x120 + ((n) * 0x40))
#define MXS_DCP_CH_N_STAT_CLR(n) (0x128 + ((n) * 0x40))
/* DMA descriptor bits. */
#define MXS_DCP_CONTROL0_HASH_TERM (1 << 13)
#define MXS_DCP_CONTROL0_HASH_INIT (1 << 12)
#define MXS_DCP_CONTROL0_PAYLOAD_KEY (1 << 11)
#define MXS_DCP_CONTROL0_CIPHER_ENCRYPT (1 << 8)
#define MXS_DCP_CONTROL0_CIPHER_INIT (1 << 9)
#define MXS_DCP_CONTROL0_ENABLE_HASH (1 << 6)
#define MXS_DCP_CONTROL0_ENABLE_CIPHER (1 << 5)
#define MXS_DCP_CONTROL0_DECR_SEMAPHORE (1 << 1)
#define MXS_DCP_CONTROL0_INTERRUPT (1 << 0)
#define MXS_DCP_CONTROL1_HASH_SELECT_SHA256 (2 << 16)
#define MXS_DCP_CONTROL1_HASH_SELECT_SHA1 (0 << 16)
#define MXS_DCP_CONTROL1_CIPHER_MODE_CBC (1 << 4)
#define MXS_DCP_CONTROL1_CIPHER_MODE_ECB (0 << 4)
#define MXS_DCP_CONTROL1_CIPHER_SELECT_AES128 (0 << 0)
static int mxs_dcp_start_dma(struct dcp_async_ctx *actx)
{
struct dcp *sdcp = global_sdcp;
const int chan = actx->chan;
uint32_t stat;
unsigned long ret;
struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
dma_addr_t desc_phys = dma_map_single(sdcp->dev, desc, sizeof(*desc),
DMA_TO_DEVICE);
reinit_completion(&sdcp->completion[chan]);
/* Clear status register. */
writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(chan));
/* Load the DMA descriptor. */
writel(desc_phys, sdcp->base + MXS_DCP_CH_N_CMDPTR(chan));
/* Increment the semaphore to start the DMA transfer. */
writel(1, sdcp->base + MXS_DCP_CH_N_SEMA(chan));
ret = wait_for_completion_timeout(&sdcp->completion[chan],
msecs_to_jiffies(1000));
if (!ret) {
dev_err(sdcp->dev, "Channel %i timeout (DCP_STAT=0x%08x)\n",
chan, readl(sdcp->base + MXS_DCP_STAT));
return -ETIMEDOUT;
}
stat = readl(sdcp->base + MXS_DCP_CH_N_STAT(chan));
if (stat & 0xff) {
dev_err(sdcp->dev, "Channel %i error (CH_STAT=0x%08x)\n",
chan, stat);
return -EINVAL;
}
dma_unmap_single(sdcp->dev, desc_phys, sizeof(*desc), DMA_TO_DEVICE);
return 0;
}
/*
* Encryption (AES128)
*/
static int mxs_dcp_run_aes(struct dcp_async_ctx *actx,
struct skcipher_request *req, int init)
{
struct dcp *sdcp = global_sdcp;
struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
int ret;
dma_addr_t key_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_key,
2 * AES_KEYSIZE_128,
DMA_TO_DEVICE);
dma_addr_t src_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_in_buf,
DCP_BUF_SZ, DMA_TO_DEVICE);
dma_addr_t dst_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_out_buf,
DCP_BUF_SZ, DMA_FROM_DEVICE);
if (actx->fill % AES_BLOCK_SIZE) {
dev_err(sdcp->dev, "Invalid block size!\n");
ret = -EINVAL;
goto aes_done_run;
}
/* Fill in the DMA descriptor. */
desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
MXS_DCP_CONTROL0_INTERRUPT |
MXS_DCP_CONTROL0_ENABLE_CIPHER;
/* Payload contains the key. */
desc->control0 |= MXS_DCP_CONTROL0_PAYLOAD_KEY;
if (rctx->enc)
desc->control0 |= MXS_DCP_CONTROL0_CIPHER_ENCRYPT;
if (init)
desc->control0 |= MXS_DCP_CONTROL0_CIPHER_INIT;
desc->control1 = MXS_DCP_CONTROL1_CIPHER_SELECT_AES128;
if (rctx->ecb)
desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_ECB;
else
desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_CBC;
desc->next_cmd_addr = 0;
desc->source = src_phys;
desc->destination = dst_phys;
desc->size = actx->fill;
desc->payload = key_phys;
desc->status = 0;
ret = mxs_dcp_start_dma(actx);
aes_done_run:
dma_unmap_single(sdcp->dev, key_phys, 2 * AES_KEYSIZE_128,
DMA_TO_DEVICE);
dma_unmap_single(sdcp->dev, src_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
dma_unmap_single(sdcp->dev, dst_phys, DCP_BUF_SZ, DMA_FROM_DEVICE);
return ret;
}
static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
{
struct dcp *sdcp = global_sdcp;
struct skcipher_request *req = skcipher_request_cast(arq);
struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
struct scatterlist *dst = req->dst;
struct scatterlist *src = req->src;
const int nents = sg_nents(req->src);
const int out_off = DCP_BUF_SZ;
uint8_t *in_buf = sdcp->coh->aes_in_buf;
uint8_t *out_buf = sdcp->coh->aes_out_buf;
uint8_t *out_tmp, *src_buf, *dst_buf = NULL;
uint32_t dst_off = 0;
uint32_t last_out_len = 0;
uint8_t *key = sdcp->coh->aes_key;
int ret = 0;
int split = 0;
unsigned int i, len, clen, rem = 0, tlen = 0;
int init = 0;
bool limit_hit = false;
actx->fill = 0;
/* Copy the key from the temporary location. */
memcpy(key, actx->key, actx->key_len);
if (!rctx->ecb) {
/* Copy the CBC IV just past the key. */
memcpy(key + AES_KEYSIZE_128, req->iv, AES_KEYSIZE_128);
/* CBC needs the INIT set. */
init = 1;
} else {
memset(key + AES_KEYSIZE_128, 0, AES_KEYSIZE_128);
}
for_each_sg(req->src, src, nents, i) {
src_buf = sg_virt(src);
len = sg_dma_len(src);
tlen += len;
limit_hit = tlen > req->cryptlen;
if (limit_hit)
len = req->cryptlen - (tlen - len);
do {
if (actx->fill + len > out_off)
clen = out_off - actx->fill;
else
clen = len;
memcpy(in_buf + actx->fill, src_buf, clen);
len -= clen;
src_buf += clen;
actx->fill += clen;
/*
* If we filled the buffer or this is the last SG,
* submit the buffer.
*/
if (actx->fill == out_off || sg_is_last(src) ||
limit_hit) {
ret = mxs_dcp_run_aes(actx, req, init);
if (ret)
return ret;
init = 0;
out_tmp = out_buf;
last_out_len = actx->fill;
while (dst && actx->fill) {
if (!split) {
dst_buf = sg_virt(dst);
dst_off = 0;
}
rem = min(sg_dma_len(dst) - dst_off,
actx->fill);
memcpy(dst_buf + dst_off, out_tmp, rem);
out_tmp += rem;
dst_off += rem;
actx->fill -= rem;
if (dst_off == sg_dma_len(dst)) {
dst = sg_next(dst);
split = 0;
} else {
split = 1;
}
}
}
} while (len);
if (limit_hit)
break;
}
/* Copy the IV for CBC for chaining */
if (!rctx->ecb) {
if (rctx->enc)
memcpy(req->iv, out_buf+(last_out_len-AES_BLOCK_SIZE),
AES_BLOCK_SIZE);
else
memcpy(req->iv, in_buf+(last_out_len-AES_BLOCK_SIZE),
AES_BLOCK_SIZE);
}
return ret;
}
static int dcp_chan_thread_aes(void *data)
{
struct dcp *sdcp = global_sdcp;
const int chan = DCP_CHAN_CRYPTO;
struct crypto_async_request *backlog;
struct crypto_async_request *arq;
int ret;
while (!kthread_should_stop()) {
set_current_state(TASK_INTERRUPTIBLE);
spin_lock(&sdcp->lock[chan]);
backlog = crypto_get_backlog(&sdcp->queue[chan]);
arq = crypto_dequeue_request(&sdcp->queue[chan]);
spin_unlock(&sdcp->lock[chan]);
if (!backlog && !arq) {
schedule();
continue;
}
set_current_state(TASK_RUNNING);
if (backlog)
backlog->complete(backlog, -EINPROGRESS);
if (arq) {
ret = mxs_dcp_aes_block_crypt(arq);
arq->complete(arq, ret);
}
}
return 0;
}
static int mxs_dcp_block_fallback(struct skcipher_request *req, int enc)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
struct dcp_async_ctx *ctx = crypto_skcipher_ctx(tfm);
int ret;
skcipher_request_set_tfm(&rctx->fallback_req, ctx->fallback);
skcipher_request_set_callback(&rctx->fallback_req, req->base.flags,
req->base.complete, req->base.data);
skcipher_request_set_crypt(&rctx->fallback_req, req->src, req->dst,
req->cryptlen, req->iv);
if (enc)
ret = crypto_skcipher_encrypt(&rctx->fallback_req);
else
ret = crypto_skcipher_decrypt(&rctx->fallback_req);
return ret;
}
static int mxs_dcp_aes_enqueue(struct skcipher_request *req, int enc, int ecb)
{
struct dcp *sdcp = global_sdcp;
struct crypto_async_request *arq = &req->base;
struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
int ret;
if (unlikely(actx->key_len != AES_KEYSIZE_128))
return mxs_dcp_block_fallback(req, enc);
rctx->enc = enc;
rctx->ecb = ecb;
actx->chan = DCP_CHAN_CRYPTO;
spin_lock(&sdcp->lock[actx->chan]);
ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
spin_unlock(&sdcp->lock[actx->chan]);
wake_up_process(sdcp->thread[actx->chan]);
return ret;
}
static int mxs_dcp_aes_ecb_decrypt(struct skcipher_request *req)
{
return mxs_dcp_aes_enqueue(req, 0, 1);
}
static int mxs_dcp_aes_ecb_encrypt(struct skcipher_request *req)
{
return mxs_dcp_aes_enqueue(req, 1, 1);
}
static int mxs_dcp_aes_cbc_decrypt(struct skcipher_request *req)
{
return mxs_dcp_aes_enqueue(req, 0, 0);
}
static int mxs_dcp_aes_cbc_encrypt(struct skcipher_request *req)
{
return mxs_dcp_aes_enqueue(req, 1, 0);
}
static int mxs_dcp_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
unsigned int len)
{
struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
/*
* AES 128 is supposed by the hardware, store key into temporary
* buffer and exit. We must use the temporary buffer here, since
* there can still be an operation in progress.
*/
actx->key_len = len;
if (len == AES_KEYSIZE_128) {
memcpy(actx->key, key, len);
return 0;
}
/*
* If the requested AES key size is not supported by the hardware,
* but is supported by in-kernel software implementation, we use
* software fallback.
*/
crypto_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK);
crypto_skcipher_set_flags(actx->fallback,
tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
return crypto_skcipher_setkey(actx->fallback, key, len);
}
static int mxs_dcp_aes_fallback_init_tfm(struct crypto_skcipher *tfm)
{
const char *name = crypto_tfm_alg_name(crypto_skcipher_tfm(tfm));
struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
struct crypto_skcipher *blk;
blk = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
if (IS_ERR(blk))
return PTR_ERR(blk);
actx->fallback = blk;
crypto_skcipher_set_reqsize(tfm, sizeof(struct dcp_aes_req_ctx) +
crypto_skcipher_reqsize(blk));
return 0;
}
static void mxs_dcp_aes_fallback_exit_tfm(struct crypto_skcipher *tfm)
{
struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
crypto_free_skcipher(actx->fallback);
}
/*
* Hashing (SHA1/SHA256)
*/
static int mxs_dcp_run_sha(struct ahash_request *req)
{
struct dcp *sdcp = global_sdcp;
int ret;
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
dma_addr_t digest_phys = 0;
dma_addr_t buf_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_in_buf,
DCP_BUF_SZ, DMA_TO_DEVICE);
/* Fill in the DMA descriptor. */
desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
MXS_DCP_CONTROL0_INTERRUPT |
MXS_DCP_CONTROL0_ENABLE_HASH;
if (rctx->init)
desc->control0 |= MXS_DCP_CONTROL0_HASH_INIT;
desc->control1 = actx->alg;
desc->next_cmd_addr = 0;
desc->source = buf_phys;
desc->destination = 0;
desc->size = actx->fill;
desc->payload = 0;
desc->status = 0;
/*
* Align driver with hw behavior when generating null hashes
*/
if (rctx->init && rctx->fini && desc->size == 0) {
struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
const uint8_t *sha_buf =
(actx->alg == MXS_DCP_CONTROL1_HASH_SELECT_SHA1) ?
sha1_null_hash : sha256_null_hash;
memcpy(sdcp->coh->sha_out_buf, sha_buf, halg->digestsize);
ret = 0;
goto done_run;
}
/* Set HASH_TERM bit for last transfer block. */
if (rctx->fini) {
digest_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_out_buf,
DCP_SHA_PAY_SZ, DMA_FROM_DEVICE);
desc->control0 |= MXS_DCP_CONTROL0_HASH_TERM;
desc->payload = digest_phys;
}
ret = mxs_dcp_start_dma(actx);
if (rctx->fini)
dma_unmap_single(sdcp->dev, digest_phys, DCP_SHA_PAY_SZ,
DMA_FROM_DEVICE);
done_run:
dma_unmap_single(sdcp->dev, buf_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
return ret;
}
static int dcp_sha_req_to_buf(struct crypto_async_request *arq)
{
struct dcp *sdcp = global_sdcp;
struct ahash_request *req = ahash_request_cast(arq);
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
uint8_t *in_buf = sdcp->coh->sha_in_buf;
uint8_t *out_buf = sdcp->coh->sha_out_buf;
struct scatterlist *src;
unsigned int i, len, clen, oft = 0;
int ret;
int fin = rctx->fini;
if (fin)
rctx->fini = 0;
src = req->src;
len = req->nbytes;
while (len) {
if (actx->fill + len > DCP_BUF_SZ)
clen = DCP_BUF_SZ - actx->fill;
else
clen = len;
scatterwalk_map_and_copy(in_buf + actx->fill, src, oft, clen,
0);
len -= clen;
oft += clen;
actx->fill += clen;
/*
* If we filled the buffer and still have some
* more data, submit the buffer.
*/
if (len && actx->fill == DCP_BUF_SZ) {
ret = mxs_dcp_run_sha(req);
if (ret)
return ret;
actx->fill = 0;
rctx->init = 0;
}
}
if (fin) {
rctx->fini = 1;
/* Submit whatever is left. */
if (!req->result)
return -EINVAL;
ret = mxs_dcp_run_sha(req);
if (ret)
return ret;
actx->fill = 0;
/* For some reason the result is flipped */
for (i = 0; i < halg->digestsize; i++)
req->result[i] = out_buf[halg->digestsize - i - 1];
}
return 0;
}
static int dcp_chan_thread_sha(void *data)
{
struct dcp *sdcp = global_sdcp;
const int chan = DCP_CHAN_HASH_SHA;
struct crypto_async_request *backlog;
struct crypto_async_request *arq;
int ret;
while (!kthread_should_stop()) {
set_current_state(TASK_INTERRUPTIBLE);
spin_lock(&sdcp->lock[chan]);
backlog = crypto_get_backlog(&sdcp->queue[chan]);
arq = crypto_dequeue_request(&sdcp->queue[chan]);
spin_unlock(&sdcp->lock[chan]);
if (!backlog && !arq) {
schedule();
continue;
}
set_current_state(TASK_RUNNING);
if (backlog)
backlog->complete(backlog, -EINPROGRESS);
if (arq) {
ret = dcp_sha_req_to_buf(arq);
arq->complete(arq, ret);
}
}
return 0;
}
static int dcp_sha_init(struct ahash_request *req)
{
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
/*
* Start hashing session. The code below only inits the
* hashing session context, nothing more.
*/
memset(actx, 0, sizeof(*actx));
if (strcmp(halg->base.cra_name, "sha1") == 0)
actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA1;
else
actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA256;
actx->fill = 0;
actx->hot = 0;
actx->chan = DCP_CHAN_HASH_SHA;
mutex_init(&actx->mutex);
return 0;
}
static int dcp_sha_update_fx(struct ahash_request *req, int fini)
{
struct dcp *sdcp = global_sdcp;
struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
int ret;
/*
* Ignore requests that have no data in them and are not
* the trailing requests in the stream of requests.
*/
if (!req->nbytes && !fini)
return 0;
mutex_lock(&actx->mutex);
rctx->fini = fini;
if (!actx->hot) {
actx->hot = 1;
rctx->init = 1;
}
spin_lock(&sdcp->lock[actx->chan]);
ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
spin_unlock(&sdcp->lock[actx->chan]);
wake_up_process(sdcp->thread[actx->chan]);
mutex_unlock(&actx->mutex);
return ret;
}
static int dcp_sha_update(struct ahash_request *req)
{
return dcp_sha_update_fx(req, 0);
}
static int dcp_sha_final(struct ahash_request *req)
{
ahash_request_set_crypt(req, NULL, req->result, 0);
req->nbytes = 0;
return dcp_sha_update_fx(req, 1);
}
static int dcp_sha_finup(struct ahash_request *req)
{
return dcp_sha_update_fx(req, 1);
}
static int dcp_sha_digest(struct ahash_request *req)
{
int ret;
ret = dcp_sha_init(req);
if (ret)
return ret;
return dcp_sha_finup(req);
}
static int dcp_sha_import(struct ahash_request *req, const void *in)
{
struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
const struct dcp_export_state *export = in;
memset(rctx, 0, sizeof(struct dcp_sha_req_ctx));
memset(actx, 0, sizeof(struct dcp_async_ctx));
memcpy(rctx, &export->req_ctx, sizeof(struct dcp_sha_req_ctx));
memcpy(actx, &export->async_ctx, sizeof(struct dcp_async_ctx));
return 0;
}
static int dcp_sha_export(struct ahash_request *req, void *out)
{
struct dcp_sha_req_ctx *rctx_state = ahash_request_ctx(req);
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
struct dcp_async_ctx *actx_state = crypto_ahash_ctx(tfm);
struct dcp_export_state *export = out;
memcpy(&export->req_ctx, rctx_state, sizeof(struct dcp_sha_req_ctx));
memcpy(&export->async_ctx, actx_state, sizeof(struct dcp_async_ctx));
return 0;
}
static int dcp_sha_cra_init(struct crypto_tfm *tfm)
{
crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
sizeof(struct dcp_sha_req_ctx));
return 0;
}
static void dcp_sha_cra_exit(struct crypto_tfm *tfm)
{
}
/* AES 128 ECB and AES 128 CBC */
static struct skcipher_alg dcp_aes_algs[] = {
{
.base.cra_name = "ecb(aes)",
.base.cra_driver_name = "ecb-aes-dcp",
.base.cra_priority = 400,
.base.cra_alignmask = 15,
.base.cra_flags = CRYPTO_ALG_ASYNC |
CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = AES_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct dcp_async_ctx),
.base.cra_module = THIS_MODULE,
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.setkey = mxs_dcp_aes_setkey,
.encrypt = mxs_dcp_aes_ecb_encrypt,
.decrypt = mxs_dcp_aes_ecb_decrypt,
.init = mxs_dcp_aes_fallback_init_tfm,
.exit = mxs_dcp_aes_fallback_exit_tfm,
}, {
.base.cra_name = "cbc(aes)",
.base.cra_driver_name = "cbc-aes-dcp",
.base.cra_priority = 400,
.base.cra_alignmask = 15,
.base.cra_flags = CRYPTO_ALG_ASYNC |
CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = AES_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct dcp_async_ctx),
.base.cra_module = THIS_MODULE,
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.setkey = mxs_dcp_aes_setkey,
.encrypt = mxs_dcp_aes_cbc_encrypt,
.decrypt = mxs_dcp_aes_cbc_decrypt,
.ivsize = AES_BLOCK_SIZE,
.init = mxs_dcp_aes_fallback_init_tfm,
.exit = mxs_dcp_aes_fallback_exit_tfm,
},
};
/* SHA1 */
static struct ahash_alg dcp_sha1_alg = {
.init = dcp_sha_init,
.update = dcp_sha_update,
.final = dcp_sha_final,
.finup = dcp_sha_finup,
.digest = dcp_sha_digest,
.import = dcp_sha_import,
.export = dcp_sha_export,
.halg = {
.digestsize = SHA1_DIGEST_SIZE,
.statesize = sizeof(struct dcp_export_state),
.base = {
.cra_name = "sha1",
.cra_driver_name = "sha1-dcp",
.cra_priority = 400,
.cra_alignmask = 63,
.cra_flags = CRYPTO_ALG_ASYNC,
.cra_blocksize = SHA1_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct dcp_async_ctx),
.cra_module = THIS_MODULE,
.cra_init = dcp_sha_cra_init,
.cra_exit = dcp_sha_cra_exit,
},
},
};
/* SHA256 */
static struct ahash_alg dcp_sha256_alg = {
.init = dcp_sha_init,
.update = dcp_sha_update,
.final = dcp_sha_final,
.finup = dcp_sha_finup,
.digest = dcp_sha_digest,
.import = dcp_sha_import,
.export = dcp_sha_export,
.halg = {
.digestsize = SHA256_DIGEST_SIZE,
.statesize = sizeof(struct dcp_export_state),
.base = {
.cra_name = "sha256",
.cra_driver_name = "sha256-dcp",
.cra_priority = 400,
.cra_alignmask = 63,
.cra_flags = CRYPTO_ALG_ASYNC,
.cra_blocksize = SHA256_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct dcp_async_ctx),
.cra_module = THIS_MODULE,
.cra_init = dcp_sha_cra_init,
.cra_exit = dcp_sha_cra_exit,
},
},
};
static irqreturn_t mxs_dcp_irq(int irq, void *context)
{
struct dcp *sdcp = context;
uint32_t stat;
int i;
stat = readl(sdcp->base + MXS_DCP_STAT);
stat &= MXS_DCP_STAT_IRQ_MASK;
if (!stat)
return IRQ_NONE;
/* Clear the interrupts. */
writel(stat, sdcp->base + MXS_DCP_STAT_CLR);
/* Complete the DMA requests that finished. */
for (i = 0; i < DCP_MAX_CHANS; i++)
if (stat & (1 << i))
complete(&sdcp->completion[i]);
return IRQ_HANDLED;
}
static int mxs_dcp_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct dcp *sdcp = NULL;
int i, ret;
int dcp_vmi_irq, dcp_irq;
if (global_sdcp) {
dev_err(dev, "Only one DCP instance allowed!\n");
return -ENODEV;
}
dcp_vmi_irq = platform_get_irq(pdev, 0);
if (dcp_vmi_irq < 0)
return dcp_vmi_irq;
dcp_irq = platform_get_irq(pdev, 1);
if (dcp_irq < 0)
return dcp_irq;
sdcp = devm_kzalloc(dev, sizeof(*sdcp), GFP_KERNEL);
if (!sdcp)
return -ENOMEM;
sdcp->dev = dev;
sdcp->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(sdcp->base))
return PTR_ERR(sdcp->base);
ret = devm_request_irq(dev, dcp_vmi_irq, mxs_dcp_irq, 0,
"dcp-vmi-irq", sdcp);
if (ret) {
dev_err(dev, "Failed to claim DCP VMI IRQ!\n");
return ret;
}
ret = devm_request_irq(dev, dcp_irq, mxs_dcp_irq, 0,
"dcp-irq", sdcp);
if (ret) {
dev_err(dev, "Failed to claim DCP IRQ!\n");
return ret;
}
/* Allocate coherent helper block. */
sdcp->coh = devm_kzalloc(dev, sizeof(*sdcp->coh) + DCP_ALIGNMENT,
GFP_KERNEL);
if (!sdcp->coh)
return -ENOMEM;
/* Re-align the structure so it fits the DCP constraints. */
sdcp->coh = PTR_ALIGN(sdcp->coh, DCP_ALIGNMENT);
/* DCP clock is optional, only used on some SOCs */
sdcp->dcp_clk = devm_clk_get(dev, "dcp");
if (IS_ERR(sdcp->dcp_clk)) {
if (sdcp->dcp_clk != ERR_PTR(-ENOENT))
return PTR_ERR(sdcp->dcp_clk);
sdcp->dcp_clk = NULL;
}
ret = clk_prepare_enable(sdcp->dcp_clk);
if (ret)
return ret;
/* Restart the DCP block. */
ret = stmp_reset_block(sdcp->base);
if (ret) {
dev_err(dev, "Failed reset\n");
goto err_disable_unprepare_clk;
}
/* Initialize control register. */
writel(MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES |
MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING | 0xf,
sdcp->base + MXS_DCP_CTRL);
/* Enable all DCP DMA channels. */
writel(MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK,
sdcp->base + MXS_DCP_CHANNELCTRL);
/*
* We do not enable context switching. Give the context buffer a
* pointer to an illegal address so if context switching is
* inadvertantly enabled, the DCP will return an error instead of
* trashing good memory. The DCP DMA cannot access ROM, so any ROM
* address will do.
*/
writel(0xffff0000, sdcp->base + MXS_DCP_CONTEXT);
for (i = 0; i < DCP_MAX_CHANS; i++)
writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(i));
writel(0xffffffff, sdcp->base + MXS_DCP_STAT_CLR);
global_sdcp = sdcp;
platform_set_drvdata(pdev, sdcp);
for (i = 0; i < DCP_MAX_CHANS; i++) {
spin_lock_init(&sdcp->lock[i]);
init_completion(&sdcp->completion[i]);
crypto_init_queue(&sdcp->queue[i], 50);
}
/* Create the SHA and AES handler threads. */
sdcp->thread[DCP_CHAN_HASH_SHA] = kthread_run(dcp_chan_thread_sha,
NULL, "mxs_dcp_chan/sha");
if (IS_ERR(sdcp->thread[DCP_CHAN_HASH_SHA])) {
dev_err(dev, "Error starting SHA thread!\n");
ret = PTR_ERR(sdcp->thread[DCP_CHAN_HASH_SHA]);
goto err_disable_unprepare_clk;
}
sdcp->thread[DCP_CHAN_CRYPTO] = kthread_run(dcp_chan_thread_aes,
NULL, "mxs_dcp_chan/aes");
if (IS_ERR(sdcp->thread[DCP_CHAN_CRYPTO])) {
dev_err(dev, "Error starting SHA thread!\n");
ret = PTR_ERR(sdcp->thread[DCP_CHAN_CRYPTO]);
goto err_destroy_sha_thread;
}
/* Register the various crypto algorithms. */
sdcp->caps = readl(sdcp->base + MXS_DCP_CAPABILITY1);
if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128) {
ret = crypto_register_skciphers(dcp_aes_algs,
ARRAY_SIZE(dcp_aes_algs));
if (ret) {
/* Failed to register algorithm. */
dev_err(dev, "Failed to register AES crypto!\n");
goto err_destroy_aes_thread;
}
}
if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1) {
ret = crypto_register_ahash(&dcp_sha1_alg);
if (ret) {
dev_err(dev, "Failed to register %s hash!\n",
dcp_sha1_alg.halg.base.cra_name);
goto err_unregister_aes;
}
}
if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256) {
ret = crypto_register_ahash(&dcp_sha256_alg);
if (ret) {
dev_err(dev, "Failed to register %s hash!\n",
dcp_sha256_alg.halg.base.cra_name);
goto err_unregister_sha1;
}
}
return 0;
err_unregister_sha1:
if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
crypto_unregister_ahash(&dcp_sha1_alg);
err_unregister_aes:
if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
crypto_unregister_skciphers(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
err_destroy_aes_thread:
kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
err_destroy_sha_thread:
kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
err_disable_unprepare_clk:
clk_disable_unprepare(sdcp->dcp_clk);
return ret;
}
static int mxs_dcp_remove(struct platform_device *pdev)
{
struct dcp *sdcp = platform_get_drvdata(pdev);
if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256)
crypto_unregister_ahash(&dcp_sha256_alg);
if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
crypto_unregister_ahash(&dcp_sha1_alg);
if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
crypto_unregister_skciphers(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
clk_disable_unprepare(sdcp->dcp_clk);
platform_set_drvdata(pdev, NULL);
global_sdcp = NULL;
return 0;
}
static const struct of_device_id mxs_dcp_dt_ids[] = {
{ .compatible = "fsl,imx23-dcp", .data = NULL, },
{ .compatible = "fsl,imx28-dcp", .data = NULL, },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, mxs_dcp_dt_ids);
static struct platform_driver mxs_dcp_driver = {
.probe = mxs_dcp_probe,
.remove = mxs_dcp_remove,
.driver = {
.name = "mxs-dcp",
.of_match_table = mxs_dcp_dt_ids,
},
};
module_platform_driver(mxs_dcp_driver);
MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
MODULE_DESCRIPTION("Freescale MXS DCP Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:mxs-dcp");