linux/drivers/crypto/atmel-sha.c

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/*
* Cryptographic API.
*
* Support for ATMEL SHA1/SHA256 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-sham.c drivers.
*/
#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/delay.h>
#include <linux/crypto.h>
#include <linux/cryptohash.h>
#include <crypto/scatterwalk.h>
#include <crypto/algapi.h>
#include <crypto/sha.h>
#include <crypto/hash.h>
#include <crypto/internal/hash.h>
#include "atmel-sha-regs.h"
/* SHA flags */
#define SHA_FLAGS_BUSY BIT(0)
#define SHA_FLAGS_FINAL BIT(1)
#define SHA_FLAGS_DMA_ACTIVE BIT(2)
#define SHA_FLAGS_OUTPUT_READY BIT(3)
#define SHA_FLAGS_INIT BIT(4)
#define SHA_FLAGS_CPU BIT(5)
#define SHA_FLAGS_DMA_READY BIT(6)
#define SHA_FLAGS_FINUP BIT(16)
#define SHA_FLAGS_SG BIT(17)
#define SHA_FLAGS_SHA1 BIT(18)
#define SHA_FLAGS_SHA256 BIT(19)
#define SHA_FLAGS_ERROR BIT(20)
#define SHA_FLAGS_PAD BIT(21)
#define SHA_FLAGS_DUALBUFF BIT(24)
#define SHA_OP_UPDATE 1
#define SHA_OP_FINAL 2
#define SHA_BUFFER_LEN PAGE_SIZE
#define ATMEL_SHA_DMA_THRESHOLD 56
struct atmel_sha_dev;
struct atmel_sha_reqctx {
struct atmel_sha_dev *dd;
unsigned long flags;
unsigned long op;
u8 digest[SHA256_DIGEST_SIZE] __aligned(sizeof(u32));
size_t digcnt;
size_t bufcnt;
size_t buflen;
dma_addr_t dma_addr;
/* walk state */
struct scatterlist *sg;
unsigned int offset; /* offset in current sg */
unsigned int total; /* total request */
u8 buffer[0] __aligned(sizeof(u32));
};
struct atmel_sha_ctx {
struct atmel_sha_dev *dd;
unsigned long flags;
/* fallback stuff */
struct crypto_shash *fallback;
};
#define ATMEL_SHA_QUEUE_LENGTH 1
struct atmel_sha_dev {
struct list_head list;
unsigned long phys_base;
struct device *dev;
struct clk *iclk;
int irq;
void __iomem *io_base;
spinlock_t lock;
int err;
struct tasklet_struct done_task;
unsigned long flags;
struct crypto_queue queue;
struct ahash_request *req;
};
struct atmel_sha_drv {
struct list_head dev_list;
spinlock_t lock;
};
static struct atmel_sha_drv atmel_sha = {
.dev_list = LIST_HEAD_INIT(atmel_sha.dev_list),
.lock = __SPIN_LOCK_UNLOCKED(atmel_sha.lock),
};
static inline u32 atmel_sha_read(struct atmel_sha_dev *dd, u32 offset)
{
return readl_relaxed(dd->io_base + offset);
}
static inline void atmel_sha_write(struct atmel_sha_dev *dd,
u32 offset, u32 value)
{
writel_relaxed(value, dd->io_base + offset);
}
static void atmel_sha_dualbuff_test(struct atmel_sha_dev *dd)
{
atmel_sha_write(dd, SHA_MR, SHA_MR_DUALBUFF);
if (atmel_sha_read(dd, SHA_MR) & SHA_MR_DUALBUFF)
dd->flags |= SHA_FLAGS_DUALBUFF;
}
static size_t atmel_sha_append_sg(struct atmel_sha_reqctx *ctx)
{
size_t count;
while ((ctx->bufcnt < ctx->buflen) && ctx->total) {
count = min(ctx->sg->length - ctx->offset, ctx->total);
count = min(count, ctx->buflen - ctx->bufcnt);
if (count <= 0)
break;
scatterwalk_map_and_copy(ctx->buffer + ctx->bufcnt, ctx->sg,
ctx->offset, count, 0);
ctx->bufcnt += count;
ctx->offset += count;
ctx->total -= count;
if (ctx->offset == ctx->sg->length) {
ctx->sg = sg_next(ctx->sg);
if (ctx->sg)
ctx->offset = 0;
else
ctx->total = 0;
}
}
return 0;
}
/*
* The purpose of this padding is to ensure that the padded message
* is a multiple of 512 bits. The bit "1" is appended at the end of
* the message followed by "padlen-1" zero bits. Then a 64 bits block
* equals to the message length in bits is appended.
*
* padlen is calculated as followed:
* - if message length < 56 bytes then padlen = 56 - message length
* - else padlen = 64 + 56 - message length
*/
static void atmel_sha_fill_padding(struct atmel_sha_reqctx *ctx, int length)
{
unsigned int index, padlen;
u64 bits;
u64 size;
bits = (ctx->bufcnt + ctx->digcnt + length) << 3;
size = cpu_to_be64(bits);
index = ctx->bufcnt & 0x3f;
padlen = (index < 56) ? (56 - index) : ((64+56) - index);
*(ctx->buffer + ctx->bufcnt) = 0x80;
memset(ctx->buffer + ctx->bufcnt + 1, 0, padlen-1);
memcpy(ctx->buffer + ctx->bufcnt + padlen, &size, 8);
ctx->bufcnt += padlen + 8;
ctx->flags |= SHA_FLAGS_PAD;
}
static int atmel_sha_init(struct ahash_request *req)
{
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
struct atmel_sha_ctx *tctx = crypto_ahash_ctx(tfm);
struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
struct atmel_sha_dev *dd = NULL;
struct atmel_sha_dev *tmp;
spin_lock_bh(&atmel_sha.lock);
if (!tctx->dd) {
list_for_each_entry(tmp, &atmel_sha.dev_list, list) {
dd = tmp;
break;
}
tctx->dd = dd;
} else {
dd = tctx->dd;
}
spin_unlock_bh(&atmel_sha.lock);
ctx->dd = dd;
ctx->flags = 0;
dev_dbg(dd->dev, "init: digest size: %d\n",
crypto_ahash_digestsize(tfm));
if (crypto_ahash_digestsize(tfm) == SHA1_DIGEST_SIZE)
ctx->flags |= SHA_FLAGS_SHA1;
else if (crypto_ahash_digestsize(tfm) == SHA256_DIGEST_SIZE)
ctx->flags |= SHA_FLAGS_SHA256;
ctx->bufcnt = 0;
ctx->digcnt = 0;
ctx->buflen = SHA_BUFFER_LEN;
return 0;
}
static void atmel_sha_write_ctrl(struct atmel_sha_dev *dd, int dma)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(dd->req);
u32 valcr = 0, valmr = SHA_MR_MODE_AUTO;
if (likely(dma)) {
atmel_sha_write(dd, SHA_IER, SHA_INT_TXBUFE);
valmr = SHA_MR_MODE_PDC;
if (dd->flags & SHA_FLAGS_DUALBUFF)
valmr = SHA_MR_DUALBUFF;
} else {
atmel_sha_write(dd, SHA_IER, SHA_INT_DATARDY);
}
if (ctx->flags & SHA_FLAGS_SHA256)
valmr |= SHA_MR_ALGO_SHA256;
/* Setting CR_FIRST only for the first iteration */
if (!ctx->digcnt)
valcr = SHA_CR_FIRST;
atmel_sha_write(dd, SHA_CR, valcr);
atmel_sha_write(dd, SHA_MR, valmr);
}
static int atmel_sha_xmit_cpu(struct atmel_sha_dev *dd, const u8 *buf,
size_t length, int final)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(dd->req);
int count, len32;
const u32 *buffer = (const u32 *)buf;
dev_dbg(dd->dev, "xmit_cpu: digcnt: %d, length: %d, final: %d\n",
ctx->digcnt, length, final);
atmel_sha_write_ctrl(dd, 0);
/* should be non-zero before next lines to disable clocks later */
ctx->digcnt += length;
if (final)
dd->flags |= SHA_FLAGS_FINAL; /* catch last interrupt */
len32 = DIV_ROUND_UP(length, sizeof(u32));
dd->flags |= SHA_FLAGS_CPU;
for (count = 0; count < len32; count++)
atmel_sha_write(dd, SHA_REG_DIN(count), buffer[count]);
return -EINPROGRESS;
}
static int atmel_sha_xmit_pdc(struct atmel_sha_dev *dd, dma_addr_t dma_addr1,
size_t length1, dma_addr_t dma_addr2, size_t length2, int final)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(dd->req);
int len32;
dev_dbg(dd->dev, "xmit_pdc: digcnt: %d, length: %d, final: %d\n",
ctx->digcnt, length1, final);
len32 = DIV_ROUND_UP(length1, sizeof(u32));
atmel_sha_write(dd, SHA_PTCR, SHA_PTCR_TXTDIS);
atmel_sha_write(dd, SHA_TPR, dma_addr1);
atmel_sha_write(dd, SHA_TCR, len32);
len32 = DIV_ROUND_UP(length2, sizeof(u32));
atmel_sha_write(dd, SHA_TNPR, dma_addr2);
atmel_sha_write(dd, SHA_TNCR, len32);
atmel_sha_write_ctrl(dd, 1);
/* should be non-zero before next lines to disable clocks later */
ctx->digcnt += length1;
if (final)
dd->flags |= SHA_FLAGS_FINAL; /* catch last interrupt */
dd->flags |= SHA_FLAGS_DMA_ACTIVE;
/* Start DMA transfer */
atmel_sha_write(dd, SHA_PTCR, SHA_PTCR_TXTEN);
return -EINPROGRESS;
}
static int atmel_sha_update_cpu(struct atmel_sha_dev *dd)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(dd->req);
int bufcnt;
atmel_sha_append_sg(ctx);
atmel_sha_fill_padding(ctx, 0);
bufcnt = ctx->bufcnt;
ctx->bufcnt = 0;
return atmel_sha_xmit_cpu(dd, ctx->buffer, bufcnt, 1);
}
static int atmel_sha_xmit_dma_map(struct atmel_sha_dev *dd,
struct atmel_sha_reqctx *ctx,
size_t length, int final)
{
ctx->dma_addr = dma_map_single(dd->dev, ctx->buffer,
ctx->buflen + SHA1_BLOCK_SIZE, DMA_TO_DEVICE);
if (dma_mapping_error(dd->dev, ctx->dma_addr)) {
dev_err(dd->dev, "dma %u bytes error\n", ctx->buflen +
SHA1_BLOCK_SIZE);
return -EINVAL;
}
ctx->flags &= ~SHA_FLAGS_SG;
/* next call does not fail... so no unmap in the case of error */
return atmel_sha_xmit_pdc(dd, ctx->dma_addr, length, 0, 0, final);
}
static int atmel_sha_update_dma_slow(struct atmel_sha_dev *dd)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(dd->req);
unsigned int final;
size_t count;
atmel_sha_append_sg(ctx);
final = (ctx->flags & SHA_FLAGS_FINUP) && !ctx->total;
dev_dbg(dd->dev, "slow: bufcnt: %u, digcnt: %d, final: %d\n",
ctx->bufcnt, ctx->digcnt, final);
if (final)
atmel_sha_fill_padding(ctx, 0);
if (final || (ctx->bufcnt == ctx->buflen && ctx->total)) {
count = ctx->bufcnt;
ctx->bufcnt = 0;
return atmel_sha_xmit_dma_map(dd, ctx, count, final);
}
return 0;
}
static int atmel_sha_update_dma_start(struct atmel_sha_dev *dd)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(dd->req);
unsigned int length, final, tail;
struct scatterlist *sg;
unsigned int count;
if (!ctx->total)
return 0;
if (ctx->bufcnt || ctx->offset)
return atmel_sha_update_dma_slow(dd);
dev_dbg(dd->dev, "fast: digcnt: %d, bufcnt: %u, total: %u\n",
ctx->digcnt, ctx->bufcnt, ctx->total);
sg = ctx->sg;
if (!IS_ALIGNED(sg->offset, sizeof(u32)))
return atmel_sha_update_dma_slow(dd);
if (!sg_is_last(sg) && !IS_ALIGNED(sg->length, SHA1_BLOCK_SIZE))
/* size is not SHA1_BLOCK_SIZE aligned */
return atmel_sha_update_dma_slow(dd);
length = min(ctx->total, sg->length);
if (sg_is_last(sg)) {
if (!(ctx->flags & SHA_FLAGS_FINUP)) {
/* not last sg must be SHA1_BLOCK_SIZE aligned */
tail = length & (SHA1_BLOCK_SIZE - 1);
length -= tail;
if (length == 0) {
/* offset where to start slow */
ctx->offset = length;
return atmel_sha_update_dma_slow(dd);
}
}
}
ctx->total -= length;
ctx->offset = length; /* offset where to start slow */
final = (ctx->flags & SHA_FLAGS_FINUP) && !ctx->total;
/* Add padding */
if (final) {
tail = length & (SHA1_BLOCK_SIZE - 1);
length -= tail;
ctx->total += tail;
ctx->offset = length; /* offset where to start slow */
sg = ctx->sg;
atmel_sha_append_sg(ctx);
atmel_sha_fill_padding(ctx, length);
ctx->dma_addr = dma_map_single(dd->dev, ctx->buffer,
ctx->buflen + SHA1_BLOCK_SIZE, DMA_TO_DEVICE);
if (dma_mapping_error(dd->dev, ctx->dma_addr)) {
dev_err(dd->dev, "dma %u bytes error\n",
ctx->buflen + SHA1_BLOCK_SIZE);
return -EINVAL;
}
if (length == 0) {
ctx->flags &= ~SHA_FLAGS_SG;
count = ctx->bufcnt;
ctx->bufcnt = 0;
return atmel_sha_xmit_pdc(dd, ctx->dma_addr, count, 0,
0, final);
} else {
ctx->sg = sg;
if (!dma_map_sg(dd->dev, ctx->sg, 1,
DMA_TO_DEVICE)) {
dev_err(dd->dev, "dma_map_sg error\n");
return -EINVAL;
}
ctx->flags |= SHA_FLAGS_SG;
count = ctx->bufcnt;
ctx->bufcnt = 0;
return atmel_sha_xmit_pdc(dd, sg_dma_address(ctx->sg),
length, ctx->dma_addr, count, final);
}
}
if (!dma_map_sg(dd->dev, ctx->sg, 1, DMA_TO_DEVICE)) {
dev_err(dd->dev, "dma_map_sg error\n");
return -EINVAL;
}
ctx->flags |= SHA_FLAGS_SG;
/* next call does not fail... so no unmap in the case of error */
return atmel_sha_xmit_pdc(dd, sg_dma_address(ctx->sg), length, 0,
0, final);
}
static int atmel_sha_update_dma_stop(struct atmel_sha_dev *dd)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(dd->req);
if (ctx->flags & SHA_FLAGS_SG) {
dma_unmap_sg(dd->dev, ctx->sg, 1, DMA_TO_DEVICE);
if (ctx->sg->length == ctx->offset) {
ctx->sg = sg_next(ctx->sg);
if (ctx->sg)
ctx->offset = 0;
}
if (ctx->flags & SHA_FLAGS_PAD)
dma_unmap_single(dd->dev, ctx->dma_addr,
ctx->buflen + SHA1_BLOCK_SIZE, DMA_TO_DEVICE);
} else {
dma_unmap_single(dd->dev, ctx->dma_addr, ctx->buflen +
SHA1_BLOCK_SIZE, DMA_TO_DEVICE);
}
return 0;
}
static int atmel_sha_update_req(struct atmel_sha_dev *dd)
{
struct ahash_request *req = dd->req;
struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
int err;
dev_dbg(dd->dev, "update_req: total: %u, digcnt: %d, finup: %d\n",
ctx->total, ctx->digcnt, (ctx->flags & SHA_FLAGS_FINUP) != 0);
if (ctx->flags & SHA_FLAGS_CPU)
err = atmel_sha_update_cpu(dd);
else
err = atmel_sha_update_dma_start(dd);
/* wait for dma completion before can take more data */
dev_dbg(dd->dev, "update: err: %d, digcnt: %d\n",
err, ctx->digcnt);
return err;
}
static int atmel_sha_final_req(struct atmel_sha_dev *dd)
{
struct ahash_request *req = dd->req;
struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
int err = 0;
int count;
if (ctx->bufcnt >= ATMEL_SHA_DMA_THRESHOLD) {
atmel_sha_fill_padding(ctx, 0);
count = ctx->bufcnt;
ctx->bufcnt = 0;
err = atmel_sha_xmit_dma_map(dd, ctx, count, 1);
}
/* faster to handle last block with cpu */
else {
atmel_sha_fill_padding(ctx, 0);
count = ctx->bufcnt;
ctx->bufcnt = 0;
err = atmel_sha_xmit_cpu(dd, ctx->buffer, count, 1);
}
dev_dbg(dd->dev, "final_req: err: %d\n", err);
return err;
}
static void atmel_sha_copy_hash(struct ahash_request *req)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
u32 *hash = (u32 *)ctx->digest;
int i;
if (likely(ctx->flags & SHA_FLAGS_SHA1))
for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(u32); i++)
hash[i] = atmel_sha_read(ctx->dd, SHA_REG_DIGEST(i));
else
for (i = 0; i < SHA256_DIGEST_SIZE / sizeof(u32); i++)
hash[i] = atmel_sha_read(ctx->dd, SHA_REG_DIGEST(i));
}
static void atmel_sha_copy_ready_hash(struct ahash_request *req)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
if (!req->result)
return;
if (likely(ctx->flags & SHA_FLAGS_SHA1))
memcpy(req->result, ctx->digest, SHA1_DIGEST_SIZE);
else
memcpy(req->result, ctx->digest, SHA256_DIGEST_SIZE);
}
static int atmel_sha_finish(struct ahash_request *req)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
struct atmel_sha_dev *dd = ctx->dd;
int err = 0;
if (ctx->digcnt)
atmel_sha_copy_ready_hash(req);
dev_dbg(dd->dev, "digcnt: %d, bufcnt: %d\n", ctx->digcnt,
ctx->bufcnt);
return err;
}
static void atmel_sha_finish_req(struct ahash_request *req, int err)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
struct atmel_sha_dev *dd = ctx->dd;
if (!err) {
atmel_sha_copy_hash(req);
if (SHA_FLAGS_FINAL & dd->flags)
err = atmel_sha_finish(req);
} else {
ctx->flags |= SHA_FLAGS_ERROR;
}
/* atomic operation is not needed here */
dd->flags &= ~(SHA_FLAGS_BUSY | SHA_FLAGS_FINAL | SHA_FLAGS_CPU |
SHA_FLAGS_DMA_READY | SHA_FLAGS_OUTPUT_READY);
clk_disable_unprepare(dd->iclk);
if (req->base.complete)
req->base.complete(&req->base, err);
/* handle new request */
tasklet_schedule(&dd->done_task);
}
static int atmel_sha_hw_init(struct atmel_sha_dev *dd)
{
clk_prepare_enable(dd->iclk);
if (SHA_FLAGS_INIT & dd->flags) {
atmel_sha_write(dd, SHA_CR, SHA_CR_SWRST);
atmel_sha_dualbuff_test(dd);
dd->flags |= SHA_FLAGS_INIT;
dd->err = 0;
}
return 0;
}
static int atmel_sha_handle_queue(struct atmel_sha_dev *dd,
struct ahash_request *req)
{
struct crypto_async_request *async_req, *backlog;
struct atmel_sha_reqctx *ctx;
unsigned long flags;
int err = 0, ret = 0;
spin_lock_irqsave(&dd->lock, flags);
if (req)
ret = ahash_enqueue_request(&dd->queue, req);
if (SHA_FLAGS_BUSY & dd->flags) {
spin_unlock_irqrestore(&dd->lock, flags);
return ret;
}
backlog = crypto_get_backlog(&dd->queue);
async_req = crypto_dequeue_request(&dd->queue);
if (async_req)
dd->flags |= SHA_FLAGS_BUSY;
spin_unlock_irqrestore(&dd->lock, flags);
if (!async_req)
return ret;
if (backlog)
backlog->complete(backlog, -EINPROGRESS);
req = ahash_request_cast(async_req);
dd->req = req;
ctx = ahash_request_ctx(req);
dev_dbg(dd->dev, "handling new req, op: %lu, nbytes: %d\n",
ctx->op, req->nbytes);
err = atmel_sha_hw_init(dd);
if (err)
goto err1;
if (ctx->op == SHA_OP_UPDATE) {
err = atmel_sha_update_req(dd);
if (err != -EINPROGRESS && (ctx->flags & SHA_FLAGS_FINUP)) {
/* no final() after finup() */
err = atmel_sha_final_req(dd);
}
} else if (ctx->op == SHA_OP_FINAL) {
err = atmel_sha_final_req(dd);
}
err1:
if (err != -EINPROGRESS)
/* done_task will not finish it, so do it here */
atmel_sha_finish_req(req, err);
dev_dbg(dd->dev, "exit, err: %d\n", err);
return ret;
}
static int atmel_sha_enqueue(struct ahash_request *req, unsigned int op)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
struct atmel_sha_ctx *tctx = crypto_tfm_ctx(req->base.tfm);
struct atmel_sha_dev *dd = tctx->dd;
ctx->op = op;
return atmel_sha_handle_queue(dd, req);
}
static int atmel_sha_update(struct ahash_request *req)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
if (!req->nbytes)
return 0;
ctx->total = req->nbytes;
ctx->sg = req->src;
ctx->offset = 0;
if (ctx->flags & SHA_FLAGS_FINUP) {
if (ctx->bufcnt + ctx->total < ATMEL_SHA_DMA_THRESHOLD)
/* faster to use CPU for short transfers */
ctx->flags |= SHA_FLAGS_CPU;
} else if (ctx->bufcnt + ctx->total < ctx->buflen) {
atmel_sha_append_sg(ctx);
return 0;
}
return atmel_sha_enqueue(req, SHA_OP_UPDATE);
}
static int atmel_sha_final(struct ahash_request *req)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
struct atmel_sha_ctx *tctx = crypto_tfm_ctx(req->base.tfm);
struct atmel_sha_dev *dd = tctx->dd;
int err = 0;
ctx->flags |= SHA_FLAGS_FINUP;
if (ctx->flags & SHA_FLAGS_ERROR)
return 0; /* uncompleted hash is not needed */
if (ctx->bufcnt) {
return atmel_sha_enqueue(req, SHA_OP_FINAL);
} else if (!(ctx->flags & SHA_FLAGS_PAD)) { /* add padding */
err = atmel_sha_hw_init(dd);
if (err)
goto err1;
dd->flags |= SHA_FLAGS_BUSY;
err = atmel_sha_final_req(dd);
} else {
/* copy ready hash (+ finalize hmac) */
return atmel_sha_finish(req);
}
err1:
if (err != -EINPROGRESS)
/* done_task will not finish it, so do it here */
atmel_sha_finish_req(req, err);
return err;
}
static int atmel_sha_finup(struct ahash_request *req)
{
struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
int err1, err2;
ctx->flags |= SHA_FLAGS_FINUP;
err1 = atmel_sha_update(req);
if (err1 == -EINPROGRESS || err1 == -EBUSY)
return err1;
/*
* final() has to be always called to cleanup resources
* even if udpate() failed, except EINPROGRESS
*/
err2 = atmel_sha_final(req);
return err1 ?: err2;
}
static int atmel_sha_digest(struct ahash_request *req)
{
return atmel_sha_init(req) ?: atmel_sha_finup(req);
}
static int atmel_sha_cra_init_alg(struct crypto_tfm *tfm, const char *alg_base)
{
struct atmel_sha_ctx *tctx = crypto_tfm_ctx(tfm);
const char *alg_name = crypto_tfm_alg_name(tfm);
/* Allocate a fallback and abort if it failed. */
tctx->fallback = crypto_alloc_shash(alg_name, 0,
CRYPTO_ALG_NEED_FALLBACK);
if (IS_ERR(tctx->fallback)) {
pr_err("atmel-sha: fallback driver '%s' could not be loaded.\n",
alg_name);
return PTR_ERR(tctx->fallback);
}
crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
sizeof(struct atmel_sha_reqctx) +
SHA_BUFFER_LEN + SHA256_BLOCK_SIZE);
return 0;
}
static int atmel_sha_cra_init(struct crypto_tfm *tfm)
{
return atmel_sha_cra_init_alg(tfm, NULL);
}
static void atmel_sha_cra_exit(struct crypto_tfm *tfm)
{
struct atmel_sha_ctx *tctx = crypto_tfm_ctx(tfm);
crypto_free_shash(tctx->fallback);
tctx->fallback = NULL;
}
static struct ahash_alg sha_algs[] = {
{
.init = atmel_sha_init,
.update = atmel_sha_update,
.final = atmel_sha_final,
.finup = atmel_sha_finup,
.digest = atmel_sha_digest,
.halg = {
.digestsize = SHA1_DIGEST_SIZE,
.base = {
.cra_name = "sha1",
.cra_driver_name = "atmel-sha1",
.cra_priority = 100,
.cra_flags = CRYPTO_ALG_ASYNC |
CRYPTO_ALG_NEED_FALLBACK,
.cra_blocksize = SHA1_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct atmel_sha_ctx),
.cra_alignmask = 0,
.cra_module = THIS_MODULE,
.cra_init = atmel_sha_cra_init,
.cra_exit = atmel_sha_cra_exit,
}
}
},
{
.init = atmel_sha_init,
.update = atmel_sha_update,
.final = atmel_sha_final,
.finup = atmel_sha_finup,
.digest = atmel_sha_digest,
.halg = {
.digestsize = SHA256_DIGEST_SIZE,
.base = {
.cra_name = "sha256",
.cra_driver_name = "atmel-sha256",
.cra_priority = 100,
.cra_flags = CRYPTO_ALG_ASYNC |
CRYPTO_ALG_NEED_FALLBACK,
.cra_blocksize = SHA256_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct atmel_sha_ctx),
.cra_alignmask = 0,
.cra_module = THIS_MODULE,
.cra_init = atmel_sha_cra_init,
.cra_exit = atmel_sha_cra_exit,
}
}
},
};
static void atmel_sha_done_task(unsigned long data)
{
struct atmel_sha_dev *dd = (struct atmel_sha_dev *)data;
int err = 0;
if (!(SHA_FLAGS_BUSY & dd->flags)) {
atmel_sha_handle_queue(dd, NULL);
return;
}
if (SHA_FLAGS_CPU & dd->flags) {
if (SHA_FLAGS_OUTPUT_READY & dd->flags) {
dd->flags &= ~SHA_FLAGS_OUTPUT_READY;
goto finish;
}
} else if (SHA_FLAGS_DMA_READY & dd->flags) {
if (SHA_FLAGS_DMA_ACTIVE & dd->flags) {
dd->flags &= ~SHA_FLAGS_DMA_ACTIVE;
atmel_sha_update_dma_stop(dd);
if (dd->err) {
err = dd->err;
goto finish;
}
}
if (SHA_FLAGS_OUTPUT_READY & dd->flags) {
/* hash or semi-hash ready */
dd->flags &= ~(SHA_FLAGS_DMA_READY |
SHA_FLAGS_OUTPUT_READY);
err = atmel_sha_update_dma_start(dd);
if (err != -EINPROGRESS)
goto finish;
}
}
return;
finish:
/* finish curent request */
atmel_sha_finish_req(dd->req, err);
}
static irqreturn_t atmel_sha_irq(int irq, void *dev_id)
{
struct atmel_sha_dev *sha_dd = dev_id;
u32 reg;
reg = atmel_sha_read(sha_dd, SHA_ISR);
if (reg & atmel_sha_read(sha_dd, SHA_IMR)) {
atmel_sha_write(sha_dd, SHA_IDR, reg);
if (SHA_FLAGS_BUSY & sha_dd->flags) {
sha_dd->flags |= SHA_FLAGS_OUTPUT_READY;
if (!(SHA_FLAGS_CPU & sha_dd->flags))
sha_dd->flags |= SHA_FLAGS_DMA_READY;
tasklet_schedule(&sha_dd->done_task);
} else {
dev_warn(sha_dd->dev, "SHA interrupt when no active requests.\n");
}
return IRQ_HANDLED;
}
return IRQ_NONE;
}
static void atmel_sha_unregister_algs(struct atmel_sha_dev *dd)
{
int i;
for (i = 0; i < ARRAY_SIZE(sha_algs); i++)
crypto_unregister_ahash(&sha_algs[i]);
}
static int atmel_sha_register_algs(struct atmel_sha_dev *dd)
{
int err, i, j;
for (i = 0; i < ARRAY_SIZE(sha_algs); i++) {
err = crypto_register_ahash(&sha_algs[i]);
if (err)
goto err_sha_algs;
}
return 0;
err_sha_algs:
for (j = 0; j < i; j++)
crypto_unregister_ahash(&sha_algs[j]);
return err;
}
static int atmel_sha_probe(struct platform_device *pdev)
{
struct atmel_sha_dev *sha_dd;
struct device *dev = &pdev->dev;
struct resource *sha_res;
unsigned long sha_phys_size;
int err;
sha_dd = kzalloc(sizeof(struct atmel_sha_dev), GFP_KERNEL);
if (sha_dd == NULL) {
dev_err(dev, "unable to alloc data struct.\n");
err = -ENOMEM;
goto sha_dd_err;
}
sha_dd->dev = dev;
platform_set_drvdata(pdev, sha_dd);
INIT_LIST_HEAD(&sha_dd->list);
tasklet_init(&sha_dd->done_task, atmel_sha_done_task,
(unsigned long)sha_dd);
crypto_init_queue(&sha_dd->queue, ATMEL_SHA_QUEUE_LENGTH);
sha_dd->irq = -1;
/* Get the base address */
sha_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!sha_res) {
dev_err(dev, "no MEM resource info\n");
err = -ENODEV;
goto res_err;
}
sha_dd->phys_base = sha_res->start;
sha_phys_size = resource_size(sha_res);
/* Get the IRQ */
sha_dd->irq = platform_get_irq(pdev, 0);
if (sha_dd->irq < 0) {
dev_err(dev, "no IRQ resource info\n");
err = sha_dd->irq;
goto res_err;
}
err = request_irq(sha_dd->irq, atmel_sha_irq, IRQF_SHARED, "atmel-sha",
sha_dd);
if (err) {
dev_err(dev, "unable to request sha irq.\n");
goto res_err;
}
/* Initializing the clock */
sha_dd->iclk = clk_get(&pdev->dev, NULL);
if (IS_ERR(sha_dd->iclk)) {
dev_err(dev, "clock intialization failed.\n");
err = PTR_ERR(sha_dd->iclk);
goto clk_err;
}
sha_dd->io_base = ioremap(sha_dd->phys_base, sha_phys_size);
if (!sha_dd->io_base) {
dev_err(dev, "can't ioremap\n");
err = -ENOMEM;
goto sha_io_err;
}
spin_lock(&atmel_sha.lock);
list_add_tail(&sha_dd->list, &atmel_sha.dev_list);
spin_unlock(&atmel_sha.lock);
err = atmel_sha_register_algs(sha_dd);
if (err)
goto err_algs;
dev_info(dev, "Atmel SHA1/SHA256\n");
return 0;
err_algs:
spin_lock(&atmel_sha.lock);
list_del(&sha_dd->list);
spin_unlock(&atmel_sha.lock);
iounmap(sha_dd->io_base);
sha_io_err:
clk_put(sha_dd->iclk);
clk_err:
free_irq(sha_dd->irq, sha_dd);
res_err:
tasklet_kill(&sha_dd->done_task);
kfree(sha_dd);
sha_dd = NULL;
sha_dd_err:
dev_err(dev, "initialization failed.\n");
return err;
}
static int atmel_sha_remove(struct platform_device *pdev)
{
static struct atmel_sha_dev *sha_dd;
sha_dd = platform_get_drvdata(pdev);
if (!sha_dd)
return -ENODEV;
spin_lock(&atmel_sha.lock);
list_del(&sha_dd->list);
spin_unlock(&atmel_sha.lock);
atmel_sha_unregister_algs(sha_dd);
tasklet_kill(&sha_dd->done_task);
iounmap(sha_dd->io_base);
clk_put(sha_dd->iclk);
if (sha_dd->irq >= 0)
free_irq(sha_dd->irq, sha_dd);
kfree(sha_dd);
sha_dd = NULL;
return 0;
}
static struct platform_driver atmel_sha_driver = {
.probe = atmel_sha_probe,
.remove = atmel_sha_remove,
.driver = {
.name = "atmel_sha",
.owner = THIS_MODULE,
},
};
module_platform_driver(atmel_sha_driver);
MODULE_DESCRIPTION("Atmel SHA1/SHA256 hw acceleration support.");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Nicolas Royer - Eukréa Electromatique");