linux/drivers/crypto/atmel-aes.c
Cyrille Pitchen bbe628ed89 crypto: atmel-aes - improve performances of data transfer
This patch totally reworks data transfer.

1 - DMA

The new code now fully supports scatter-gather lists hence reducing the
number of interrupts in some cases. Also buffer alignments are better
managed to avoid useless copies.

2 - CPU

The new code allows to use PIO accesses even when transferring more than
one AES block, so futher patches could tune the DMA threshold
(ATMEL_AES_DMA_THRESHOLD).
Moreover, CPU transfers now have a chance to be processed synchronously,
hence reducing the latency by avoiding context switches when possible
(less interrupts to process, less scheduling of the 'done' task).
Indeed the 'DATA READY' bit is polled only one time in the Interrupt
Status Register before enabling then waiting for the associated interrupt.
In some condition, this single poll is enough as the data have already
been processed by the AES hardware and so are ready.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-12-23 18:19:55 +08:00

1499 lines
34 KiB
C

/*
* Cryptographic API.
*
* Support for ATMEL AES HW acceleration.
*
* Copyright (c) 2012 Eukréa Electromatique - ATMEL
* Author: Nicolas Royer <nicolas@eukrea.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* Some ideas are from omap-aes.c driver.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/hw_random.h>
#include <linux/platform_device.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <linux/of_device.h>
#include <linux/delay.h>
#include <linux/crypto.h>
#include <crypto/scatterwalk.h>
#include <crypto/algapi.h>
#include <crypto/aes.h>
#include <linux/platform_data/crypto-atmel.h>
#include <dt-bindings/dma/at91.h>
#include "atmel-aes-regs.h"
#define ATMEL_AES_PRIORITY 300
#define ATMEL_AES_BUFFER_ORDER 2
#define ATMEL_AES_BUFFER_SIZE (PAGE_SIZE << ATMEL_AES_BUFFER_ORDER)
#define CFB8_BLOCK_SIZE 1
#define CFB16_BLOCK_SIZE 2
#define CFB32_BLOCK_SIZE 4
#define CFB64_BLOCK_SIZE 8
#define SIZE_IN_WORDS(x) ((x) >> 2)
/* AES flags */
/* Reserve bits [18:16] [14:12] [0] for mode (same as for AES_MR) */
#define AES_FLAGS_ENCRYPT AES_MR_CYPHER_ENC
#define AES_FLAGS_OPMODE_MASK (AES_MR_OPMOD_MASK | AES_MR_CFBS_MASK)
#define AES_FLAGS_ECB AES_MR_OPMOD_ECB
#define AES_FLAGS_CBC AES_MR_OPMOD_CBC
#define AES_FLAGS_OFB AES_MR_OPMOD_OFB
#define AES_FLAGS_CFB128 (AES_MR_OPMOD_CFB | AES_MR_CFBS_128b)
#define AES_FLAGS_CFB64 (AES_MR_OPMOD_CFB | AES_MR_CFBS_64b)
#define AES_FLAGS_CFB32 (AES_MR_OPMOD_CFB | AES_MR_CFBS_32b)
#define AES_FLAGS_CFB16 (AES_MR_OPMOD_CFB | AES_MR_CFBS_16b)
#define AES_FLAGS_CFB8 (AES_MR_OPMOD_CFB | AES_MR_CFBS_8b)
#define AES_FLAGS_CTR AES_MR_OPMOD_CTR
#define AES_FLAGS_MODE_MASK (AES_FLAGS_OPMODE_MASK | \
AES_FLAGS_ENCRYPT)
#define AES_FLAGS_INIT BIT(2)
#define AES_FLAGS_BUSY BIT(3)
#define AES_FLAGS_PERSISTENT (AES_FLAGS_INIT | AES_FLAGS_BUSY)
#define ATMEL_AES_QUEUE_LENGTH 50
#define ATMEL_AES_DMA_THRESHOLD 16
struct atmel_aes_caps {
bool has_dualbuff;
bool has_cfb64;
u32 max_burst_size;
};
struct atmel_aes_dev;
typedef int (*atmel_aes_fn_t)(struct atmel_aes_dev *);
struct atmel_aes_base_ctx {
struct atmel_aes_dev *dd;
atmel_aes_fn_t start;
int keylen;
u32 key[AES_KEYSIZE_256 / sizeof(u32)];
u16 block_size;
};
struct atmel_aes_ctx {
struct atmel_aes_base_ctx base;
};
struct atmel_aes_reqctx {
unsigned long mode;
};
struct atmel_aes_dma {
struct dma_chan *chan;
struct scatterlist *sg;
int nents;
unsigned int remainder;
unsigned int sg_len;
};
struct atmel_aes_dev {
struct list_head list;
unsigned long phys_base;
void __iomem *io_base;
struct crypto_async_request *areq;
struct atmel_aes_base_ctx *ctx;
bool is_async;
atmel_aes_fn_t resume;
atmel_aes_fn_t cpu_transfer_complete;
struct device *dev;
struct clk *iclk;
int irq;
unsigned long flags;
spinlock_t lock;
struct crypto_queue queue;
struct tasklet_struct done_task;
struct tasklet_struct queue_task;
size_t total;
size_t datalen;
u32 *data;
struct atmel_aes_dma src;
struct atmel_aes_dma dst;
size_t buflen;
void *buf;
struct scatterlist aligned_sg;
struct scatterlist *real_dst;
struct atmel_aes_caps caps;
u32 hw_version;
};
struct atmel_aes_drv {
struct list_head dev_list;
spinlock_t lock;
};
static struct atmel_aes_drv atmel_aes = {
.dev_list = LIST_HEAD_INIT(atmel_aes.dev_list),
.lock = __SPIN_LOCK_UNLOCKED(atmel_aes.lock),
};
static inline u32 atmel_aes_read(struct atmel_aes_dev *dd, u32 offset)
{
return readl_relaxed(dd->io_base + offset);
}
static inline void atmel_aes_write(struct atmel_aes_dev *dd,
u32 offset, u32 value)
{
writel_relaxed(value, dd->io_base + offset);
}
static void atmel_aes_read_n(struct atmel_aes_dev *dd, u32 offset,
u32 *value, int count)
{
for (; count--; value++, offset += 4)
*value = atmel_aes_read(dd, offset);
}
static void atmel_aes_write_n(struct atmel_aes_dev *dd, u32 offset,
const u32 *value, int count)
{
for (; count--; value++, offset += 4)
atmel_aes_write(dd, offset, *value);
}
static inline void atmel_aes_read_block(struct atmel_aes_dev *dd, u32 offset,
u32 *value)
{
atmel_aes_read_n(dd, offset, value, SIZE_IN_WORDS(AES_BLOCK_SIZE));
}
static inline void atmel_aes_write_block(struct atmel_aes_dev *dd, u32 offset,
const u32 *value)
{
atmel_aes_write_n(dd, offset, value, SIZE_IN_WORDS(AES_BLOCK_SIZE));
}
static inline int atmel_aes_wait_for_data_ready(struct atmel_aes_dev *dd,
atmel_aes_fn_t resume)
{
u32 isr = atmel_aes_read(dd, AES_ISR);
if (unlikely(isr & AES_INT_DATARDY))
return resume(dd);
dd->resume = resume;
atmel_aes_write(dd, AES_IER, AES_INT_DATARDY);
return -EINPROGRESS;
}
static inline size_t atmel_aes_padlen(size_t len, size_t block_size)
{
len &= block_size - 1;
return len ? block_size - len : 0;
}
static struct atmel_aes_dev *atmel_aes_find_dev(struct atmel_aes_base_ctx *ctx)
{
struct atmel_aes_dev *aes_dd = NULL;
struct atmel_aes_dev *tmp;
spin_lock_bh(&atmel_aes.lock);
if (!ctx->dd) {
list_for_each_entry(tmp, &atmel_aes.dev_list, list) {
aes_dd = tmp;
break;
}
ctx->dd = aes_dd;
} else {
aes_dd = ctx->dd;
}
spin_unlock_bh(&atmel_aes.lock);
return aes_dd;
}
static int atmel_aes_hw_init(struct atmel_aes_dev *dd)
{
int err;
err = clk_prepare_enable(dd->iclk);
if (err)
return err;
if (!(dd->flags & AES_FLAGS_INIT)) {
atmel_aes_write(dd, AES_CR, AES_CR_SWRST);
atmel_aes_write(dd, AES_MR, 0xE << AES_MR_CKEY_OFFSET);
dd->flags |= AES_FLAGS_INIT;
}
return 0;
}
static inline unsigned int atmel_aes_get_version(struct atmel_aes_dev *dd)
{
return atmel_aes_read(dd, AES_HW_VERSION) & 0x00000fff;
}
static int atmel_aes_hw_version_init(struct atmel_aes_dev *dd)
{
int err;
err = atmel_aes_hw_init(dd);
if (err)
return err;
dd->hw_version = atmel_aes_get_version(dd);
dev_info(dd->dev, "version: 0x%x\n", dd->hw_version);
clk_disable_unprepare(dd->iclk);
return 0;
}
static inline void atmel_aes_set_mode(struct atmel_aes_dev *dd,
const struct atmel_aes_reqctx *rctx)
{
/* Clear all but persistent flags and set request flags. */
dd->flags = (dd->flags & AES_FLAGS_PERSISTENT) | rctx->mode;
}
static inline int atmel_aes_complete(struct atmel_aes_dev *dd, int err)
{
clk_disable_unprepare(dd->iclk);
dd->flags &= ~AES_FLAGS_BUSY;
if (dd->is_async)
dd->areq->complete(dd->areq, err);
tasklet_schedule(&dd->queue_task);
return err;
}
/* CPU transfer */
static int atmel_aes_cpu_transfer(struct atmel_aes_dev *dd)
{
int err = 0;
u32 isr;
for (;;) {
atmel_aes_read_block(dd, AES_ODATAR(0), dd->data);
dd->data += 4;
dd->datalen -= AES_BLOCK_SIZE;
if (dd->datalen < AES_BLOCK_SIZE)
break;
atmel_aes_write_block(dd, AES_IDATAR(0), dd->data);
isr = atmel_aes_read(dd, AES_ISR);
if (!(isr & AES_INT_DATARDY)) {
dd->resume = atmel_aes_cpu_transfer;
atmel_aes_write(dd, AES_IER, AES_INT_DATARDY);
return -EINPROGRESS;
}
}
if (!sg_copy_from_buffer(dd->real_dst, sg_nents(dd->real_dst),
dd->buf, dd->total))
err = -EINVAL;
if (err)
return atmel_aes_complete(dd, err);
return dd->cpu_transfer_complete(dd);
}
static int atmel_aes_cpu_start(struct atmel_aes_dev *dd,
struct scatterlist *src,
struct scatterlist *dst,
size_t len,
atmel_aes_fn_t resume)
{
size_t padlen = atmel_aes_padlen(len, AES_BLOCK_SIZE);
if (unlikely(len == 0))
return -EINVAL;
sg_copy_to_buffer(src, sg_nents(src), dd->buf, len);
dd->total = len;
dd->real_dst = dst;
dd->cpu_transfer_complete = resume;
dd->datalen = len + padlen;
dd->data = (u32 *)dd->buf;
atmel_aes_write_block(dd, AES_IDATAR(0), dd->data);
return atmel_aes_wait_for_data_ready(dd, atmel_aes_cpu_transfer);
}
/* DMA transfer */
static void atmel_aes_dma_callback(void *data);
static bool atmel_aes_check_aligned(struct atmel_aes_dev *dd,
struct scatterlist *sg,
size_t len,
struct atmel_aes_dma *dma)
{
int nents;
if (!IS_ALIGNED(len, dd->ctx->block_size))
return false;
for (nents = 0; sg; sg = sg_next(sg), ++nents) {
if (!IS_ALIGNED(sg->offset, sizeof(u32)))
return false;
if (len <= sg->length) {
if (!IS_ALIGNED(len, dd->ctx->block_size))
return false;
dma->nents = nents+1;
dma->remainder = sg->length - len;
sg->length = len;
return true;
}
if (!IS_ALIGNED(sg->length, dd->ctx->block_size))
return false;
len -= sg->length;
}
return false;
}
static inline void atmel_aes_restore_sg(const struct atmel_aes_dma *dma)
{
struct scatterlist *sg = dma->sg;
int nents = dma->nents;
if (!dma->remainder)
return;
while (--nents > 0 && sg)
sg = sg_next(sg);
if (!sg)
return;
sg->length += dma->remainder;
}
static int atmel_aes_map(struct atmel_aes_dev *dd,
struct scatterlist *src,
struct scatterlist *dst,
size_t len)
{
bool src_aligned, dst_aligned;
size_t padlen;
dd->total = len;
dd->src.sg = src;
dd->dst.sg = dst;
dd->real_dst = dst;
src_aligned = atmel_aes_check_aligned(dd, src, len, &dd->src);
if (src == dst)
dst_aligned = src_aligned;
else
dst_aligned = atmel_aes_check_aligned(dd, dst, len, &dd->dst);
if (!src_aligned || !dst_aligned) {
padlen = atmel_aes_padlen(len, dd->ctx->block_size);
if (dd->buflen < len + padlen)
return -ENOMEM;
if (!src_aligned) {
sg_copy_to_buffer(src, sg_nents(src), dd->buf, len);
dd->src.sg = &dd->aligned_sg;
dd->src.nents = 1;
dd->src.remainder = 0;
}
if (!dst_aligned) {
dd->dst.sg = &dd->aligned_sg;
dd->dst.nents = 1;
dd->dst.remainder = 0;
}
sg_init_table(&dd->aligned_sg, 1);
sg_set_buf(&dd->aligned_sg, dd->buf, len + padlen);
}
if (dd->src.sg == dd->dst.sg) {
dd->src.sg_len = dma_map_sg(dd->dev, dd->src.sg, dd->src.nents,
DMA_BIDIRECTIONAL);
dd->dst.sg_len = dd->src.sg_len;
if (!dd->src.sg_len)
return -EFAULT;
} else {
dd->src.sg_len = dma_map_sg(dd->dev, dd->src.sg, dd->src.nents,
DMA_TO_DEVICE);
if (!dd->src.sg_len)
return -EFAULT;
dd->dst.sg_len = dma_map_sg(dd->dev, dd->dst.sg, dd->dst.nents,
DMA_FROM_DEVICE);
if (!dd->dst.sg_len) {
dma_unmap_sg(dd->dev, dd->src.sg, dd->src.nents,
DMA_TO_DEVICE);
return -EFAULT;
}
}
return 0;
}
static void atmel_aes_unmap(struct atmel_aes_dev *dd)
{
if (dd->src.sg == dd->dst.sg) {
dma_unmap_sg(dd->dev, dd->src.sg, dd->src.nents,
DMA_BIDIRECTIONAL);
if (dd->src.sg != &dd->aligned_sg)
atmel_aes_restore_sg(&dd->src);
} else {
dma_unmap_sg(dd->dev, dd->dst.sg, dd->dst.nents,
DMA_FROM_DEVICE);
if (dd->dst.sg != &dd->aligned_sg)
atmel_aes_restore_sg(&dd->dst);
dma_unmap_sg(dd->dev, dd->src.sg, dd->src.nents,
DMA_TO_DEVICE);
if (dd->src.sg != &dd->aligned_sg)
atmel_aes_restore_sg(&dd->src);
}
if (dd->dst.sg == &dd->aligned_sg)
sg_copy_from_buffer(dd->real_dst, sg_nents(dd->real_dst),
dd->buf, dd->total);
}
static int atmel_aes_dma_transfer_start(struct atmel_aes_dev *dd,
enum dma_slave_buswidth addr_width,
enum dma_transfer_direction dir,
u32 maxburst)
{
struct dma_async_tx_descriptor *desc;
struct dma_slave_config config;
dma_async_tx_callback callback;
struct atmel_aes_dma *dma;
int err;
memset(&config, 0, sizeof(config));
config.direction = dir;
config.src_addr_width = addr_width;
config.dst_addr_width = addr_width;
config.src_maxburst = maxburst;
config.dst_maxburst = maxburst;
switch (dir) {
case DMA_MEM_TO_DEV:
dma = &dd->src;
callback = NULL;
config.dst_addr = dd->phys_base + AES_IDATAR(0);
break;
case DMA_DEV_TO_MEM:
dma = &dd->dst;
callback = atmel_aes_dma_callback;
config.src_addr = dd->phys_base + AES_ODATAR(0);
break;
default:
return -EINVAL;
}
err = dmaengine_slave_config(dma->chan, &config);
if (err)
return err;
desc = dmaengine_prep_slave_sg(dma->chan, dma->sg, dma->sg_len, dir,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc)
return -ENOMEM;
desc->callback = callback;
desc->callback_param = dd;
dmaengine_submit(desc);
dma_async_issue_pending(dma->chan);
return 0;
}
static void atmel_aes_dma_transfer_stop(struct atmel_aes_dev *dd,
enum dma_transfer_direction dir)
{
struct atmel_aes_dma *dma;
switch (dir) {
case DMA_MEM_TO_DEV:
dma = &dd->src;
break;
case DMA_DEV_TO_MEM:
dma = &dd->dst;
break;
default:
return;
}
dmaengine_terminate_all(dma->chan);
}
static int atmel_aes_dma_start(struct atmel_aes_dev *dd,
struct scatterlist *src,
struct scatterlist *dst,
size_t len,
atmel_aes_fn_t resume)
{
enum dma_slave_buswidth addr_width;
u32 maxburst;
int err;
switch (dd->ctx->block_size) {
case CFB8_BLOCK_SIZE:
addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
maxburst = 1;
break;
case CFB16_BLOCK_SIZE:
addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
maxburst = 1;
break;
case CFB32_BLOCK_SIZE:
case CFB64_BLOCK_SIZE:
addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
maxburst = 1;
break;
case AES_BLOCK_SIZE:
addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
maxburst = dd->caps.max_burst_size;
break;
default:
err = -EINVAL;
goto exit;
}
err = atmel_aes_map(dd, src, dst, len);
if (err)
goto exit;
dd->resume = resume;
/* Set output DMA transfer first */
err = atmel_aes_dma_transfer_start(dd, addr_width, DMA_DEV_TO_MEM,
maxburst);
if (err)
goto unmap;
/* Then set input DMA transfer */
err = atmel_aes_dma_transfer_start(dd, addr_width, DMA_MEM_TO_DEV,
maxburst);
if (err)
goto output_transfer_stop;
return -EINPROGRESS;
output_transfer_stop:
atmel_aes_dma_transfer_stop(dd, DMA_DEV_TO_MEM);
unmap:
atmel_aes_unmap(dd);
exit:
return atmel_aes_complete(dd, err);
}
static void atmel_aes_dma_stop(struct atmel_aes_dev *dd)
{
atmel_aes_dma_transfer_stop(dd, DMA_MEM_TO_DEV);
atmel_aes_dma_transfer_stop(dd, DMA_DEV_TO_MEM);
atmel_aes_unmap(dd);
}
static void atmel_aes_dma_callback(void *data)
{
struct atmel_aes_dev *dd = data;
atmel_aes_dma_stop(dd);
dd->is_async = true;
(void)dd->resume(dd);
}
static void atmel_aes_write_ctrl(struct atmel_aes_dev *dd, bool use_dma,
const u32 *iv)
{
u32 valmr = 0;
/* MR register must be set before IV registers */
if (dd->ctx->keylen == AES_KEYSIZE_128)
valmr |= AES_MR_KEYSIZE_128;
else if (dd->ctx->keylen == AES_KEYSIZE_192)
valmr |= AES_MR_KEYSIZE_192;
else
valmr |= AES_MR_KEYSIZE_256;
valmr |= dd->flags & AES_FLAGS_MODE_MASK;
if (use_dma) {
valmr |= AES_MR_SMOD_IDATAR0;
if (dd->caps.has_dualbuff)
valmr |= AES_MR_DUALBUFF;
} else {
valmr |= AES_MR_SMOD_AUTO;
}
atmel_aes_write(dd, AES_MR, valmr);
atmel_aes_write_n(dd, AES_KEYWR(0), dd->ctx->key,
dd->ctx->keylen >> 2);
if (iv && (valmr & AES_MR_OPMOD_MASK) != AES_MR_OPMOD_ECB)
atmel_aes_write_n(dd, AES_IVR(0), iv, 4);
}
static int atmel_aes_handle_queue(struct atmel_aes_dev *dd,
struct crypto_async_request *new_areq)
{
struct crypto_async_request *areq, *backlog;
struct atmel_aes_base_ctx *ctx;
unsigned long flags;
int err, ret = 0;
spin_lock_irqsave(&dd->lock, flags);
if (new_areq)
ret = crypto_enqueue_request(&dd->queue, new_areq);
if (dd->flags & AES_FLAGS_BUSY) {
spin_unlock_irqrestore(&dd->lock, flags);
return ret;
}
backlog = crypto_get_backlog(&dd->queue);
areq = crypto_dequeue_request(&dd->queue);
if (areq)
dd->flags |= AES_FLAGS_BUSY;
spin_unlock_irqrestore(&dd->lock, flags);
if (!areq)
return ret;
if (backlog)
backlog->complete(backlog, -EINPROGRESS);
ctx = crypto_tfm_ctx(areq->tfm);
dd->areq = areq;
dd->ctx = ctx;
dd->is_async = (areq != new_areq);
err = ctx->start(dd);
return (dd->is_async) ? ret : err;
}
static int atmel_aes_transfer_complete(struct atmel_aes_dev *dd)
{
return atmel_aes_complete(dd, 0);
}
static int atmel_aes_start(struct atmel_aes_dev *dd)
{
struct ablkcipher_request *req = ablkcipher_request_cast(dd->areq);
struct atmel_aes_reqctx *rctx = ablkcipher_request_ctx(req);
bool use_dma = (req->nbytes >= ATMEL_AES_DMA_THRESHOLD ||
dd->ctx->block_size != AES_BLOCK_SIZE);
int err;
atmel_aes_set_mode(dd, rctx);
err = atmel_aes_hw_init(dd);
if (err)
return atmel_aes_complete(dd, err);
atmel_aes_write_ctrl(dd, use_dma, req->info);
if (use_dma)
return atmel_aes_dma_start(dd, req->src, req->dst, req->nbytes,
atmel_aes_transfer_complete);
return atmel_aes_cpu_start(dd, req->src, req->dst, req->nbytes,
atmel_aes_transfer_complete);
}
static int atmel_aes_buff_init(struct atmel_aes_dev *dd)
{
dd->buf = (void *)__get_free_pages(GFP_KERNEL, ATMEL_AES_BUFFER_ORDER);
dd->buflen = ATMEL_AES_BUFFER_SIZE;
dd->buflen &= ~(AES_BLOCK_SIZE - 1);
if (!dd->buf) {
dev_err(dd->dev, "unable to alloc pages.\n");
return -ENOMEM;
}
return 0;
}
static void atmel_aes_buff_cleanup(struct atmel_aes_dev *dd)
{
free_page((unsigned long)dd->buf);
}
static int atmel_aes_crypt(struct ablkcipher_request *req, unsigned long mode)
{
struct atmel_aes_base_ctx *ctx = crypto_ablkcipher_ctx(
crypto_ablkcipher_reqtfm(req));
struct atmel_aes_reqctx *rctx = ablkcipher_request_ctx(req);
struct atmel_aes_dev *dd;
switch (mode & AES_FLAGS_OPMODE_MASK) {
case AES_FLAGS_CFB8:
ctx->block_size = CFB8_BLOCK_SIZE;
break;
case AES_FLAGS_CFB16:
ctx->block_size = CFB16_BLOCK_SIZE;
break;
case AES_FLAGS_CFB32:
ctx->block_size = CFB32_BLOCK_SIZE;
break;
case AES_FLAGS_CFB64:
ctx->block_size = CFB64_BLOCK_SIZE;
break;
default:
ctx->block_size = AES_BLOCK_SIZE;
break;
}
dd = atmel_aes_find_dev(ctx);
if (!dd)
return -ENODEV;
rctx->mode = mode;
return atmel_aes_handle_queue(dd, &req->base);
}
static bool atmel_aes_filter(struct dma_chan *chan, void *slave)
{
struct at_dma_slave *sl = slave;
if (sl && sl->dma_dev == chan->device->dev) {
chan->private = sl;
return true;
} else {
return false;
}
}
static int atmel_aes_dma_init(struct atmel_aes_dev *dd,
struct crypto_platform_data *pdata)
{
struct at_dma_slave *slave;
int err = -ENOMEM;
dma_cap_mask_t mask;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
/* Try to grab 2 DMA channels */
slave = &pdata->dma_slave->rxdata;
dd->src.chan = dma_request_slave_channel_compat(mask, atmel_aes_filter,
slave, dd->dev, "tx");
if (!dd->src.chan)
goto err_dma_in;
slave = &pdata->dma_slave->txdata;
dd->dst.chan = dma_request_slave_channel_compat(mask, atmel_aes_filter,
slave, dd->dev, "rx");
if (!dd->dst.chan)
goto err_dma_out;
return 0;
err_dma_out:
dma_release_channel(dd->src.chan);
err_dma_in:
dev_warn(dd->dev, "no DMA channel available\n");
return err;
}
static void atmel_aes_dma_cleanup(struct atmel_aes_dev *dd)
{
dma_release_channel(dd->dst.chan);
dma_release_channel(dd->src.chan);
}
static int atmel_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
unsigned int keylen)
{
struct atmel_aes_base_ctx *ctx = crypto_ablkcipher_ctx(tfm);
if (keylen != AES_KEYSIZE_128 && keylen != AES_KEYSIZE_192 &&
keylen != AES_KEYSIZE_256) {
crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
return -EINVAL;
}
memcpy(ctx->key, key, keylen);
ctx->keylen = keylen;
return 0;
}
static int atmel_aes_ecb_encrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req, AES_FLAGS_ECB | AES_FLAGS_ENCRYPT);
}
static int atmel_aes_ecb_decrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req, AES_FLAGS_ECB);
}
static int atmel_aes_cbc_encrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req,
AES_FLAGS_ENCRYPT | AES_FLAGS_CBC);
}
static int atmel_aes_cbc_decrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req,
AES_FLAGS_CBC);
}
static int atmel_aes_ofb_encrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req,
AES_FLAGS_ENCRYPT | AES_FLAGS_OFB);
}
static int atmel_aes_ofb_decrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req,
AES_FLAGS_OFB);
}
static int atmel_aes_cfb_encrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req, AES_FLAGS_CFB128 | AES_FLAGS_ENCRYPT);
}
static int atmel_aes_cfb_decrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req, AES_FLAGS_CFB128);
}
static int atmel_aes_cfb64_encrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req, AES_FLAGS_CFB64 | AES_FLAGS_ENCRYPT);
}
static int atmel_aes_cfb64_decrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req, AES_FLAGS_CFB64);
}
static int atmel_aes_cfb32_encrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req, AES_FLAGS_CFB32 | AES_FLAGS_ENCRYPT);
}
static int atmel_aes_cfb32_decrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req, AES_FLAGS_CFB32);
}
static int atmel_aes_cfb16_encrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req, AES_FLAGS_CFB16 | AES_FLAGS_ENCRYPT);
}
static int atmel_aes_cfb16_decrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req, AES_FLAGS_CFB16);
}
static int atmel_aes_cfb8_encrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req, AES_FLAGS_CFB8 | AES_FLAGS_ENCRYPT);
}
static int atmel_aes_cfb8_decrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req, AES_FLAGS_CFB8);
}
static int atmel_aes_ctr_encrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req,
AES_FLAGS_ENCRYPT | AES_FLAGS_CTR);
}
static int atmel_aes_ctr_decrypt(struct ablkcipher_request *req)
{
return atmel_aes_crypt(req,
AES_FLAGS_CTR);
}
static int atmel_aes_cra_init(struct crypto_tfm *tfm)
{
struct atmel_aes_ctx *ctx = crypto_tfm_ctx(tfm);
tfm->crt_ablkcipher.reqsize = sizeof(struct atmel_aes_reqctx);
ctx->base.start = atmel_aes_start;
return 0;
}
static void atmel_aes_cra_exit(struct crypto_tfm *tfm)
{
}
static struct crypto_alg aes_algs[] = {
{
.cra_name = "ecb(aes)",
.cra_driver_name = "atmel-ecb-aes",
.cra_priority = ATMEL_AES_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct atmel_aes_ctx),
.cra_alignmask = 0xf,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = atmel_aes_cra_init,
.cra_exit = atmel_aes_cra_exit,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.setkey = atmel_aes_setkey,
.encrypt = atmel_aes_ecb_encrypt,
.decrypt = atmel_aes_ecb_decrypt,
}
},
{
.cra_name = "cbc(aes)",
.cra_driver_name = "atmel-cbc-aes",
.cra_priority = ATMEL_AES_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct atmel_aes_ctx),
.cra_alignmask = 0xf,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = atmel_aes_cra_init,
.cra_exit = atmel_aes_cra_exit,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = atmel_aes_setkey,
.encrypt = atmel_aes_cbc_encrypt,
.decrypt = atmel_aes_cbc_decrypt,
}
},
{
.cra_name = "ofb(aes)",
.cra_driver_name = "atmel-ofb-aes",
.cra_priority = ATMEL_AES_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct atmel_aes_ctx),
.cra_alignmask = 0xf,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = atmel_aes_cra_init,
.cra_exit = atmel_aes_cra_exit,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = atmel_aes_setkey,
.encrypt = atmel_aes_ofb_encrypt,
.decrypt = atmel_aes_ofb_decrypt,
}
},
{
.cra_name = "cfb(aes)",
.cra_driver_name = "atmel-cfb-aes",
.cra_priority = ATMEL_AES_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct atmel_aes_ctx),
.cra_alignmask = 0xf,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = atmel_aes_cra_init,
.cra_exit = atmel_aes_cra_exit,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = atmel_aes_setkey,
.encrypt = atmel_aes_cfb_encrypt,
.decrypt = atmel_aes_cfb_decrypt,
}
},
{
.cra_name = "cfb32(aes)",
.cra_driver_name = "atmel-cfb32-aes",
.cra_priority = ATMEL_AES_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = CFB32_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct atmel_aes_ctx),
.cra_alignmask = 0x3,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = atmel_aes_cra_init,
.cra_exit = atmel_aes_cra_exit,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = atmel_aes_setkey,
.encrypt = atmel_aes_cfb32_encrypt,
.decrypt = atmel_aes_cfb32_decrypt,
}
},
{
.cra_name = "cfb16(aes)",
.cra_driver_name = "atmel-cfb16-aes",
.cra_priority = ATMEL_AES_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = CFB16_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct atmel_aes_ctx),
.cra_alignmask = 0x1,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = atmel_aes_cra_init,
.cra_exit = atmel_aes_cra_exit,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = atmel_aes_setkey,
.encrypt = atmel_aes_cfb16_encrypt,
.decrypt = atmel_aes_cfb16_decrypt,
}
},
{
.cra_name = "cfb8(aes)",
.cra_driver_name = "atmel-cfb8-aes",
.cra_priority = ATMEL_AES_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = CFB8_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct atmel_aes_ctx),
.cra_alignmask = 0x0,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = atmel_aes_cra_init,
.cra_exit = atmel_aes_cra_exit,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = atmel_aes_setkey,
.encrypt = atmel_aes_cfb8_encrypt,
.decrypt = atmel_aes_cfb8_decrypt,
}
},
{
.cra_name = "ctr(aes)",
.cra_driver_name = "atmel-ctr-aes",
.cra_priority = ATMEL_AES_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct atmel_aes_ctx),
.cra_alignmask = 0xf,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = atmel_aes_cra_init,
.cra_exit = atmel_aes_cra_exit,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = atmel_aes_setkey,
.encrypt = atmel_aes_ctr_encrypt,
.decrypt = atmel_aes_ctr_decrypt,
}
},
};
static struct crypto_alg aes_cfb64_alg = {
.cra_name = "cfb64(aes)",
.cra_driver_name = "atmel-cfb64-aes",
.cra_priority = ATMEL_AES_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = CFB64_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct atmel_aes_ctx),
.cra_alignmask = 0x7,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = atmel_aes_cra_init,
.cra_exit = atmel_aes_cra_exit,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = atmel_aes_setkey,
.encrypt = atmel_aes_cfb64_encrypt,
.decrypt = atmel_aes_cfb64_decrypt,
}
};
static void atmel_aes_queue_task(unsigned long data)
{
struct atmel_aes_dev *dd = (struct atmel_aes_dev *)data;
atmel_aes_handle_queue(dd, NULL);
}
static void atmel_aes_done_task(unsigned long data)
{
struct atmel_aes_dev *dd = (struct atmel_aes_dev *) data;
dd->is_async = true;
(void)dd->resume(dd);
}
static irqreturn_t atmel_aes_irq(int irq, void *dev_id)
{
struct atmel_aes_dev *aes_dd = dev_id;
u32 reg;
reg = atmel_aes_read(aes_dd, AES_ISR);
if (reg & atmel_aes_read(aes_dd, AES_IMR)) {
atmel_aes_write(aes_dd, AES_IDR, reg);
if (AES_FLAGS_BUSY & aes_dd->flags)
tasklet_schedule(&aes_dd->done_task);
else
dev_warn(aes_dd->dev, "AES interrupt when no active requests.\n");
return IRQ_HANDLED;
}
return IRQ_NONE;
}
static void atmel_aes_unregister_algs(struct atmel_aes_dev *dd)
{
int i;
if (dd->caps.has_cfb64)
crypto_unregister_alg(&aes_cfb64_alg);
for (i = 0; i < ARRAY_SIZE(aes_algs); i++)
crypto_unregister_alg(&aes_algs[i]);
}
static int atmel_aes_register_algs(struct atmel_aes_dev *dd)
{
int err, i, j;
for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
err = crypto_register_alg(&aes_algs[i]);
if (err)
goto err_aes_algs;
}
if (dd->caps.has_cfb64) {
err = crypto_register_alg(&aes_cfb64_alg);
if (err)
goto err_aes_cfb64_alg;
}
return 0;
err_aes_cfb64_alg:
i = ARRAY_SIZE(aes_algs);
err_aes_algs:
for (j = 0; j < i; j++)
crypto_unregister_alg(&aes_algs[j]);
return err;
}
static void atmel_aes_get_cap(struct atmel_aes_dev *dd)
{
dd->caps.has_dualbuff = 0;
dd->caps.has_cfb64 = 0;
dd->caps.max_burst_size = 1;
/* keep only major version number */
switch (dd->hw_version & 0xff0) {
case 0x500:
dd->caps.has_dualbuff = 1;
dd->caps.has_cfb64 = 1;
dd->caps.max_burst_size = 4;
break;
case 0x200:
dd->caps.has_dualbuff = 1;
dd->caps.has_cfb64 = 1;
dd->caps.max_burst_size = 4;
break;
case 0x130:
dd->caps.has_dualbuff = 1;
dd->caps.has_cfb64 = 1;
dd->caps.max_burst_size = 4;
break;
case 0x120:
break;
default:
dev_warn(dd->dev,
"Unmanaged aes version, set minimum capabilities\n");
break;
}
}
#if defined(CONFIG_OF)
static const struct of_device_id atmel_aes_dt_ids[] = {
{ .compatible = "atmel,at91sam9g46-aes" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, atmel_aes_dt_ids);
static struct crypto_platform_data *atmel_aes_of_init(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct crypto_platform_data *pdata;
if (!np) {
dev_err(&pdev->dev, "device node not found\n");
return ERR_PTR(-EINVAL);
}
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata) {
dev_err(&pdev->dev, "could not allocate memory for pdata\n");
return ERR_PTR(-ENOMEM);
}
pdata->dma_slave = devm_kzalloc(&pdev->dev,
sizeof(*(pdata->dma_slave)),
GFP_KERNEL);
if (!pdata->dma_slave) {
dev_err(&pdev->dev, "could not allocate memory for dma_slave\n");
devm_kfree(&pdev->dev, pdata);
return ERR_PTR(-ENOMEM);
}
return pdata;
}
#else
static inline struct crypto_platform_data *atmel_aes_of_init(struct platform_device *pdev)
{
return ERR_PTR(-EINVAL);
}
#endif
static int atmel_aes_probe(struct platform_device *pdev)
{
struct atmel_aes_dev *aes_dd;
struct crypto_platform_data *pdata;
struct device *dev = &pdev->dev;
struct resource *aes_res;
int err;
pdata = pdev->dev.platform_data;
if (!pdata) {
pdata = atmel_aes_of_init(pdev);
if (IS_ERR(pdata)) {
err = PTR_ERR(pdata);
goto aes_dd_err;
}
}
if (!pdata->dma_slave) {
err = -ENXIO;
goto aes_dd_err;
}
aes_dd = devm_kzalloc(&pdev->dev, sizeof(*aes_dd), GFP_KERNEL);
if (aes_dd == NULL) {
dev_err(dev, "unable to alloc data struct.\n");
err = -ENOMEM;
goto aes_dd_err;
}
aes_dd->dev = dev;
platform_set_drvdata(pdev, aes_dd);
INIT_LIST_HEAD(&aes_dd->list);
spin_lock_init(&aes_dd->lock);
tasklet_init(&aes_dd->done_task, atmel_aes_done_task,
(unsigned long)aes_dd);
tasklet_init(&aes_dd->queue_task, atmel_aes_queue_task,
(unsigned long)aes_dd);
crypto_init_queue(&aes_dd->queue, ATMEL_AES_QUEUE_LENGTH);
aes_dd->irq = -1;
/* Get the base address */
aes_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!aes_res) {
dev_err(dev, "no MEM resource info\n");
err = -ENODEV;
goto res_err;
}
aes_dd->phys_base = aes_res->start;
/* Get the IRQ */
aes_dd->irq = platform_get_irq(pdev, 0);
if (aes_dd->irq < 0) {
dev_err(dev, "no IRQ resource info\n");
err = aes_dd->irq;
goto res_err;
}
err = devm_request_irq(&pdev->dev, aes_dd->irq, atmel_aes_irq,
IRQF_SHARED, "atmel-aes", aes_dd);
if (err) {
dev_err(dev, "unable to request aes irq.\n");
goto res_err;
}
/* Initializing the clock */
aes_dd->iclk = devm_clk_get(&pdev->dev, "aes_clk");
if (IS_ERR(aes_dd->iclk)) {
dev_err(dev, "clock initialization failed.\n");
err = PTR_ERR(aes_dd->iclk);
goto res_err;
}
aes_dd->io_base = devm_ioremap_resource(&pdev->dev, aes_res);
if (!aes_dd->io_base) {
dev_err(dev, "can't ioremap\n");
err = -ENOMEM;
goto res_err;
}
err = atmel_aes_hw_version_init(aes_dd);
if (err)
goto res_err;
atmel_aes_get_cap(aes_dd);
err = atmel_aes_buff_init(aes_dd);
if (err)
goto err_aes_buff;
err = atmel_aes_dma_init(aes_dd, pdata);
if (err)
goto err_aes_dma;
spin_lock(&atmel_aes.lock);
list_add_tail(&aes_dd->list, &atmel_aes.dev_list);
spin_unlock(&atmel_aes.lock);
err = atmel_aes_register_algs(aes_dd);
if (err)
goto err_algs;
dev_info(dev, "Atmel AES - Using %s, %s for DMA transfers\n",
dma_chan_name(aes_dd->src.chan),
dma_chan_name(aes_dd->dst.chan));
return 0;
err_algs:
spin_lock(&atmel_aes.lock);
list_del(&aes_dd->list);
spin_unlock(&atmel_aes.lock);
atmel_aes_dma_cleanup(aes_dd);
err_aes_dma:
atmel_aes_buff_cleanup(aes_dd);
err_aes_buff:
res_err:
tasklet_kill(&aes_dd->done_task);
tasklet_kill(&aes_dd->queue_task);
aes_dd_err:
dev_err(dev, "initialization failed.\n");
return err;
}
static int atmel_aes_remove(struct platform_device *pdev)
{
static struct atmel_aes_dev *aes_dd;
aes_dd = platform_get_drvdata(pdev);
if (!aes_dd)
return -ENODEV;
spin_lock(&atmel_aes.lock);
list_del(&aes_dd->list);
spin_unlock(&atmel_aes.lock);
atmel_aes_unregister_algs(aes_dd);
tasklet_kill(&aes_dd->done_task);
tasklet_kill(&aes_dd->queue_task);
atmel_aes_dma_cleanup(aes_dd);
atmel_aes_buff_cleanup(aes_dd);
return 0;
}
static struct platform_driver atmel_aes_driver = {
.probe = atmel_aes_probe,
.remove = atmel_aes_remove,
.driver = {
.name = "atmel_aes",
.of_match_table = of_match_ptr(atmel_aes_dt_ids),
},
};
module_platform_driver(atmel_aes_driver);
MODULE_DESCRIPTION("Atmel AES hw acceleration support.");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Nicolas Royer - Eukréa Electromatique");