crypto: omap - sha1 & md5 driver

Earlier kernel contained omap sha1 and md5 driver, which was not maintained,
was not ported to new crypto APIs and removed from the source tree.

- implements async  crypto API using dma and cpu.
- supports multiple sham instances if available
- hmac
- concurrent requests

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

3 files changed, 1270 insertions, 0 deletions

diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index b08403d7d1ca..9073aa05123e 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -222,4 +222,13 @@ config CRYPTO_DEV_PPC4XX
 	help
 	  This option allows you to have support for AMCC crypto acceleration.
 
+config CRYPTO_DEV_OMAP_SHAM
+	tristate "Support for OMAP SHA1/MD5 hw accelerator"
+	depends on ARCH_OMAP2 || ARCH_OMAP3
+	select CRYPTO_SHA1
+	select CRYPTO_MD5
+	help
+	  OMAP processors have SHA1/MD5 hw accelerator. Select this if you
+	  want to use the OMAP module for SHA1/MD5 algorithms.
+
 endif # CRYPTO_HW
diff --git a/drivers/crypto/Makefile b/drivers/crypto/Makefile
index 6ffcb3f7f942..c9494e163402 100644
--- a/drivers/crypto/Makefile
+++ b/drivers/crypto/Makefile
@@ -6,3 +6,5 @@ obj-$(CONFIG_CRYPTO_DEV_MV_CESA) += mv_cesa.o
 obj-$(CONFIG_CRYPTO_DEV_TALITOS) += talitos.o
 obj-$(CONFIG_CRYPTO_DEV_IXP4XX) += ixp4xx_crypto.o
 obj-$(CONFIG_CRYPTO_DEV_PPC4XX) += amcc/
+obj-$(CONFIG_CRYPTO_DEV_OMAP_SHAM) += omap-sham.o
+
diff --git a/drivers/crypto/omap-sham.c b/drivers/crypto/omap-sham.c
new file mode 100644
index 000000000000..8b034337793f
--- /dev/null
+++ b/drivers/crypto/omap-sham.c
@@ -0,0 +1,1259 @@
+/*
+ * Cryptographic API.
+ *
+ * Support for OMAP SHA1/MD5 HW acceleration.
+ *
+ * Copyright (c) 2010 Nokia Corporation
+ * Author: Dmitry Kasatkin <dmitry.kasatkin@nokia.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 old omap-sha1-md5.c driver.
+ */
+
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+#include <linux/version.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/platform_device.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 <plat/cpu.h>
+#include <plat/dma.h>
+#include <mach/irqs.h>
+
+#define SHA_REG_DIGEST(x)		(0x00 + ((x) * 0x04))
+#define SHA_REG_DIN(x)			(0x1C + ((x) * 0x04))
+
+#define SHA1_MD5_BLOCK_SIZE		SHA1_BLOCK_SIZE
+#define MD5_DIGEST_SIZE			16
+
+#define SHA_REG_DIGCNT			0x14
+
+#define SHA_REG_CTRL			0x18
+#define SHA_REG_CTRL_LENGTH		(0xFFFFFFFF << 5)
+#define SHA_REG_CTRL_CLOSE_HASH		(1 << 4)
+#define SHA_REG_CTRL_ALGO_CONST		(1 << 3)
+#define SHA_REG_CTRL_ALGO		(1 << 2)
+#define SHA_REG_CTRL_INPUT_READY	(1 << 1)
+#define SHA_REG_CTRL_OUTPUT_READY	(1 << 0)
+
+#define SHA_REG_REV			0x5C
+#define SHA_REG_REV_MAJOR		0xF0
+#define SHA_REG_REV_MINOR		0x0F
+
+#define SHA_REG_MASK			0x60
+#define SHA_REG_MASK_DMA_EN		(1 << 3)
+#define SHA_REG_MASK_IT_EN		(1 << 2)
+#define SHA_REG_MASK_SOFTRESET		(1 << 1)
+#define SHA_REG_AUTOIDLE		(1 << 0)
+
+#define SHA_REG_SYSSTATUS		0x64
+#define SHA_REG_SYSSTATUS_RESETDONE	(1 << 0)
+
+#define DEFAULT_TIMEOUT_INTERVAL	HZ
+
+#define FLAGS_FIRST		0x0001
+#define FLAGS_FINUP		0x0002
+#define FLAGS_FINAL		0x0004
+#define FLAGS_FAST		0x0008
+#define FLAGS_SHA1		0x0010
+#define FLAGS_DMA_ACTIVE	0x0020
+#define FLAGS_OUTPUT_READY	0x0040
+#define FLAGS_CLEAN		0x0080
+#define FLAGS_INIT		0x0100
+#define FLAGS_CPU		0x0200
+#define FLAGS_HMAC		0x0400
+
+/* 3rd byte */
+#define FLAGS_BUSY		16
+
+#define OP_UPDATE	1
+#define OP_FINAL	2
+
+struct omap_sham_dev;
+
+struct omap_sham_reqctx {
+	struct omap_sham_dev	*dd;
+	unsigned long		flags;
+	unsigned long		op;
+
+	size_t			digcnt;
+	u8			*buffer;
+	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 */
+};
+
+struct omap_sham_hmac_ctx {
+	struct crypto_shash	*shash;
+	u8			ipad[SHA1_MD5_BLOCK_SIZE];
+	u8			opad[SHA1_MD5_BLOCK_SIZE];
+};
+
+struct omap_sham_ctx {
+	struct omap_sham_dev	*dd;
+
+	unsigned long		flags;
+
+	/* fallback stuff */
+	struct crypto_shash	*fallback;
+
+	struct omap_sham_hmac_ctx base[0];
+};
+
+#define OMAP_SHAM_QUEUE_LENGTH	1
+
+struct omap_sham_dev {
+	struct list_head	list;
+	unsigned long		phys_base;
+	struct device		*dev;
+	void __iomem		*io_base;
+	int			irq;
+	struct clk		*iclk;
+	spinlock_t		lock;
+	int			dma;
+	int			dma_lch;
+	struct tasklet_struct	done_task;
+	struct tasklet_struct	queue_task;
+
+	unsigned long		flags;
+	struct crypto_queue	queue;
+	struct ahash_request	*req;
+};
+
+struct omap_sham_drv {
+	struct list_head	dev_list;
+	spinlock_t		lock;
+	unsigned long		flags;
+};
+
+static struct omap_sham_drv sham = {
+	.dev_list = LIST_HEAD_INIT(sham.dev_list),
+	.lock = __SPIN_LOCK_UNLOCKED(sham.lock),
+};
+
+static inline u32 omap_sham_read(struct omap_sham_dev *dd, u32 offset)
+{
+	return __raw_readl(dd->io_base + offset);
+}
+
+static inline void omap_sham_write(struct omap_sham_dev *dd,
+					u32 offset, u32 value)
+{
+	__raw_writel(value, dd->io_base + offset);
+}
+
+static inline void omap_sham_write_mask(struct omap_sham_dev *dd, u32 address,
+					u32 value, u32 mask)
+{
+	u32 val;
+
+	val = omap_sham_read(dd, address);
+	val &= ~mask;
+	val |= value;
+	omap_sham_write(dd, address, val);
+}
+
+static inline int omap_sham_wait(struct omap_sham_dev *dd, u32 offset, u32 bit)
+{
+	unsigned long timeout = jiffies + DEFAULT_TIMEOUT_INTERVAL;
+
+	while (!(omap_sham_read(dd, offset) & bit)) {
+		if (time_is_before_jiffies(timeout))
+			return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static void omap_sham_copy_hash(struct ahash_request *req, int out)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
+	u32 *hash = (u32 *)req->result;
+	int i;
+
+	if (likely(ctx->flags & FLAGS_SHA1)) {
+		/* SHA1 results are in big endian */
+		for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(u32); i++)
+			if (out)
+				hash[i] = be32_to_cpu(omap_sham_read(ctx->dd,
+							SHA_REG_DIGEST(i)));
+			else
+				omap_sham_write(ctx->dd, SHA_REG_DIGEST(i),
+							cpu_to_be32(hash[i]));
+	} else {
+		/* MD5 results are in little endian */
+		for (i = 0; i < MD5_DIGEST_SIZE / sizeof(u32); i++)
+			if (out)
+				hash[i] = le32_to_cpu(omap_sham_read(ctx->dd,
+							SHA_REG_DIGEST(i)));
+			else
+				omap_sham_write(ctx->dd, SHA_REG_DIGEST(i),
+							cpu_to_le32(hash[i]));
+	}
+}
+
+static int omap_sham_write_ctrl(struct omap_sham_dev *dd, size_t length,
+				 int final, int dma)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
+	u32 val = length << 5, mask;
+
+	if (unlikely(!ctx->digcnt)) {
+
+		clk_enable(dd->iclk);
+
+		if (!(dd->flags & FLAGS_INIT)) {
+			omap_sham_write_mask(dd, SHA_REG_MASK,
+				SHA_REG_MASK_SOFTRESET, SHA_REG_MASK_SOFTRESET);
+
+			if (omap_sham_wait(dd, SHA_REG_SYSSTATUS,
+						SHA_REG_SYSSTATUS_RESETDONE))
+				return -ETIMEDOUT;
+
+			dd->flags |= FLAGS_INIT;
+		}
+	} else {
+		omap_sham_write(dd, SHA_REG_DIGCNT, ctx->digcnt);
+	}
+
+	omap_sham_write_mask(dd, SHA_REG_MASK,
+		SHA_REG_MASK_IT_EN | (dma ? SHA_REG_MASK_DMA_EN : 0),
+		SHA_REG_MASK_IT_EN | SHA_REG_MASK_DMA_EN);
+	/*
+	 * Setting ALGO_CONST only for the first iteration
+	 * and CLOSE_HASH only for the last one.
+	 */
+	if (ctx->flags & FLAGS_SHA1)
+		val |= SHA_REG_CTRL_ALGO;
+	if (!ctx->digcnt)
+		val |= SHA_REG_CTRL_ALGO_CONST;
+	if (final)
+		val |= SHA_REG_CTRL_CLOSE_HASH;
+
+	mask = SHA_REG_CTRL_ALGO_CONST | SHA_REG_CTRL_CLOSE_HASH |
+			SHA_REG_CTRL_ALGO | SHA_REG_CTRL_LENGTH;
+
+	omap_sham_write_mask(dd, SHA_REG_CTRL, val, mask);
+
+	return 0;
+}
+
+static int omap_sham_xmit_cpu(struct omap_sham_dev *dd, const u8 *buf,
+			      size_t length, int final)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
+	int err, 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);
+
+	err = omap_sham_write_ctrl(dd, length, final, 0);
+	if (err)
+		return err;
+
+	if (omap_sham_wait(dd, SHA_REG_CTRL, SHA_REG_CTRL_INPUT_READY))
+		return -ETIMEDOUT;
+
+	ctx->digcnt += length;
+
+	if (final)
+		ctx->flags |= FLAGS_FINAL; /* catch last interrupt */
+
+	len32 = DIV_ROUND_UP(length, sizeof(u32));
+
+	for (count = 0; count < len32; count++)
+		omap_sham_write(dd, SHA_REG_DIN(count), buffer[count]);
+
+	return -EINPROGRESS;
+}
+
+static int omap_sham_xmit_dma(struct omap_sham_dev *dd, dma_addr_t dma_addr,
+			      size_t length, int final)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
+	int err, len32;
+
+	dev_dbg(dd->dev, "xmit_dma: digcnt: %d, length: %d, final: %d\n",
+						ctx->digcnt, length, final);
+
+	/* flush cache entries related to our page */
+	if (dma_addr == ctx->dma_addr)
+		dma_sync_single_for_device(dd->dev, dma_addr, length,
+					   DMA_TO_DEVICE);
+
+	len32 = DIV_ROUND_UP(length, sizeof(u32));
+
+	omap_set_dma_transfer_params(dd->dma_lch, OMAP_DMA_DATA_TYPE_S32, len32,
+			1, OMAP_DMA_SYNC_PACKET, dd->dma, OMAP_DMA_DST_SYNC);
+
+	omap_set_dma_src_params(dd->dma_lch, 0, OMAP_DMA_AMODE_POST_INC,
+				dma_addr, 0, 0);
+
+	err = omap_sham_write_ctrl(dd, length, final, 1);
+	if (err)
+		return err;
+
+	ctx->digcnt += length;
+
+	if (final)
+		ctx->flags |= FLAGS_FINAL; /* catch last interrupt */
+
+	dd->flags |= FLAGS_DMA_ACTIVE;
+
+	omap_start_dma(dd->dma_lch);
+
+	return -EINPROGRESS;
+}
+
+static size_t omap_sham_append_buffer(struct omap_sham_reqctx *ctx,
+				const u8 *data, size_t length)
+{
+	size_t count = min(length, ctx->buflen - ctx->bufcnt);
+
+	count = min(count, ctx->total);
+	if (count <= 0)
+		return 0;
+	memcpy(ctx->buffer + ctx->bufcnt, data, count);
+	ctx->bufcnt += count;
+
+	return count;
+}
+
+static size_t omap_sham_append_sg(struct omap_sham_reqctx *ctx)
+{
+	size_t count;
+
+	while (ctx->sg) {
+		count = omap_sham_append_buffer(ctx,
+				sg_virt(ctx->sg) + ctx->offset,
+				ctx->sg->length - ctx->offset);
+		if (!count)
+			break;
+		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;
+}
+
+static int omap_sham_update_dma_slow(struct omap_sham_dev *dd)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
+	unsigned int final;
+	size_t count;
+
+	if (!ctx->total)
+		return 0;
+
+	omap_sham_append_sg(ctx);
+
+	final = (ctx->flags & FLAGS_FINUP) && !ctx->total;
+
+	dev_dbg(dd->dev, "slow: bufcnt: %u, digcnt: %d, final: %d\n",
+					 ctx->bufcnt, ctx->digcnt, final);
+
+	if (final || (ctx->bufcnt == ctx->buflen && ctx->total)) {
+		count = ctx->bufcnt;
+		ctx->bufcnt = 0;
+		return omap_sham_xmit_dma(dd, ctx->dma_addr, count, final);
+	}
+
+	return 0;
+}
+
+static int omap_sham_update_dma_fast(struct omap_sham_dev *dd)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
+	unsigned int length;
+
+	ctx->flags |= FLAGS_FAST;
+
+	length = min(ctx->total, sg_dma_len(ctx->sg));
+	ctx->total = length;
+
+	if (!dma_map_sg(dd->dev, ctx->sg, 1, DMA_TO_DEVICE)) {
+		dev_err(dd->dev, "dma_map_sg  error\n");
+		return -EINVAL;
+	}
+
+	ctx->total -= length;
+
+	return omap_sham_xmit_dma(dd, sg_dma_address(ctx->sg), length, 1);
+}
+
+static int omap_sham_update_cpu(struct omap_sham_dev *dd)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
+	int bufcnt;
+
+	omap_sham_append_sg(ctx);
+	bufcnt = ctx->bufcnt;
+	ctx->bufcnt = 0;
+
+	return omap_sham_xmit_cpu(dd, ctx->buffer, bufcnt, 1);
+}
+
+static int omap_sham_update_dma_stop(struct omap_sham_dev *dd)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
+
+	omap_stop_dma(dd->dma_lch);
+	if (ctx->flags & FLAGS_FAST)
+		dma_unmap_sg(dd->dev, ctx->sg, 1, DMA_TO_DEVICE);
+
+	return 0;
+}
+
+static void omap_sham_cleanup(struct ahash_request *req)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
+	struct omap_sham_dev *dd = ctx->dd;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dd->lock, flags);
+	if (ctx->flags & FLAGS_CLEAN) {
+		spin_unlock_irqrestore(&dd->lock, flags);
+		return;
+	}
+	ctx->flags |= FLAGS_CLEAN;
+	spin_unlock_irqrestore(&dd->lock, flags);
+
+	if (ctx->digcnt)
+		clk_disable(dd->iclk);
+
+	if (ctx->dma_addr)
+		dma_unmap_single(dd->dev, ctx->dma_addr, ctx->buflen,
+				 DMA_TO_DEVICE);
+
+	if (ctx->buffer)
+		free_page((unsigned long)ctx->buffer);
+
+	dev_dbg(dd->dev, "digcnt: %d, bufcnt: %d\n", ctx->digcnt, ctx->bufcnt);
+}
+
+static int omap_sham_init(struct ahash_request *req)
+{
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct omap_sham_ctx *tctx = crypto_ahash_ctx(tfm);
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
+	struct omap_sham_dev *dd = NULL, *tmp;
+
+	spin_lock_bh(&sham.lock);
+	if (!tctx->dd) {
+		list_for_each_entry(tmp, &sham.dev_list, list) {
+			dd = tmp;
+			break;
+		}
+		tctx->dd = dd;
+	} else {
+		dd = tctx->dd;
+	}
+	spin_unlock_bh(&sham.lock);
+
+	ctx->dd = dd;
+
+	ctx->flags = 0;
+
+	ctx->flags |= FLAGS_FIRST;
+
+	dev_dbg(dd->dev, "init: digest size: %d\n",
+		crypto_ahash_digestsize(tfm));
+
+	if (crypto_ahash_digestsize(tfm) == SHA1_DIGEST_SIZE)
+		ctx->flags |= FLAGS_SHA1;
+
+	ctx->bufcnt = 0;
+	ctx->digcnt = 0;
+
+	ctx->buflen = PAGE_SIZE;
+	ctx->buffer = (void *)__get_free_page(
+				(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
+				GFP_KERNEL : GFP_ATOMIC);
+	if (!ctx->buffer)
+		return -ENOMEM;
+
+	ctx->dma_addr = dma_map_single(dd->dev, ctx->buffer, ctx->buflen,
+					DMA_TO_DEVICE);
+	if (dma_mapping_error(dd->dev, ctx->dma_addr)) {
+		dev_err(dd->dev, "dma %u bytes error\n", ctx->buflen);
+		free_page((unsigned long)ctx->buffer);
+		return -EINVAL;
+	}
+
+	if (tctx->flags & FLAGS_HMAC) {
+		struct omap_sham_hmac_ctx *bctx = tctx->base;
+
+		memcpy(ctx->buffer, bctx->ipad, SHA1_MD5_BLOCK_SIZE);
+		ctx->bufcnt = SHA1_MD5_BLOCK_SIZE;
+		ctx->flags |= FLAGS_HMAC;
+	}
+
+	return 0;
+
+}
+
+static int omap_sham_update_req(struct omap_sham_dev *dd)
+{
+	struct ahash_request *req = dd->req;
+	struct omap_sham_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 & FLAGS_FINUP) != 0);
+
+	if (ctx->flags & FLAGS_CPU)
+		err = omap_sham_update_cpu(dd);
+	else if (ctx->flags & FLAGS_FAST)
+		err = omap_sham_update_dma_fast(dd);
+	else
+		err = omap_sham_update_dma_slow(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 omap_sham_final_req(struct omap_sham_dev *dd)
+{
+	struct ahash_request *req = dd->req;
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
+	int err = 0, use_dma = 1;
+
+	if (ctx->bufcnt <= 64)
+		/* faster to handle last block with cpu */
+		use_dma = 0;
+
+	if (use_dma)
+		err = omap_sham_xmit_dma(dd, ctx->dma_addr, ctx->bufcnt, 1);
+	else
+		err = omap_sham_xmit_cpu(dd, ctx->buffer, ctx->bufcnt, 1);
+
+	ctx->bufcnt = 0;
+
+	if (err != -EINPROGRESS)
+		omap_sham_cleanup(req);
+
+	dev_dbg(dd->dev, "final_req: err: %d\n", err);
+
+	return err;
+}
+
+static int omap_sham_finish_req_hmac(struct ahash_request *req)
+{
+	struct omap_sham_ctx *tctx = crypto_tfm_ctx(req->base.tfm);
+	struct omap_sham_hmac_ctx *bctx = tctx->base;
+	int bs = crypto_shash_blocksize(bctx->shash);
+	int ds = crypto_shash_digestsize(bctx->shash);
+	struct {
+		struct shash_desc shash;
+		char ctx[crypto_shash_descsize(bctx->shash)];
+	} desc;
+
+	desc.shash.tfm = bctx->shash;
+	desc.shash.flags = 0; /* not CRYPTO_TFM_REQ_MAY_SLEEP */
+
+	return crypto_shash_init(&desc.shash) ?:
+	       crypto_shash_update(&desc.shash, bctx->opad, bs) ?:
+	       crypto_shash_finup(&desc.shash, req->result, ds, req->result);
+}
+
+static void omap_sham_finish_req(struct ahash_request *req, int err)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
+
+	if (!err) {
+		omap_sham_copy_hash(ctx->dd->req, 1);
+		if (ctx->flags & FLAGS_HMAC)
+			err = omap_sham_finish_req_hmac(req);
+	}
+
+	if (ctx->flags & FLAGS_FINAL)
+		omap_sham_cleanup(req);
+
+	clear_bit(FLAGS_BUSY, &ctx->dd->flags);
+
+	if (req->base.complete)
+		req->base.complete(&req->base, err);
+}
+
+static int omap_sham_handle_queue(struct omap_sham_dev *dd)
+{
+	struct crypto_async_request *async_req, *backlog;
+	struct omap_sham_reqctx *ctx;
+	struct ahash_request *req, *prev_req;
+	unsigned long flags;
+	int err = 0;
+
+	if (test_and_set_bit(FLAGS_BUSY, &dd->flags))
+		return 0;
+
+	spin_lock_irqsave(&dd->lock, flags);
+	backlog = crypto_get_backlog(&dd->queue);
+	async_req = crypto_dequeue_request(&dd->queue);
+	if (!async_req)
+		clear_bit(FLAGS_BUSY, &dd->flags);
+	spin_unlock_irqrestore(&dd->lock, flags);
+
+	if (!async_req)
+		return 0;
+
+	if (backlog)
+		backlog->complete(backlog, -EINPROGRESS);
+
+	req = ahash_request_cast(async_req);
+
+	prev_req = dd->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);
+
+	if (req != prev_req && ctx->digcnt)
+		/* request has changed - restore hash */
+		omap_sham_copy_hash(req, 0);
+
+	if (ctx->op == OP_UPDATE) {
+		err = omap_sham_update_req(dd);
+		if (err != -EINPROGRESS && (ctx->flags & FLAGS_FINUP))
+			/* no final() after finup() */
+			err = omap_sham_final_req(dd);
+	} else if (ctx->op == OP_FINAL) {
+		err = omap_sham_final_req(dd);
+	}
+
+	if (err != -EINPROGRESS) {
+		/* done_task will not finish it, so do it here */
+		omap_sham_finish_req(req, err);
+		tasklet_schedule(&dd->queue_task);
+	}
+
+	dev_dbg(dd->dev, "exit, err: %d\n", err);
+
+	return err;
+}
+
+static int omap_sham_enqueue(struct ahash_request *req, unsigned int op)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
+	struct omap_sham_ctx *tctx = crypto_tfm_ctx(req->base.tfm);
+	struct omap_sham_dev *dd = tctx->dd;
+	unsigned long flags;
+	int err;
+
+	ctx->op = op;
+
+	spin_lock_irqsave(&dd->lock, flags);
+	err = ahash_enqueue_request(&dd->queue, req);
+	spin_unlock_irqrestore(&dd->lock, flags);
+
+	omap_sham_handle_queue(dd);
+
+	return err;
+}
+
+static int omap_sham_update(struct ahash_request *req)
+{
+	struct omap_sham_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 & FLAGS_FINUP) {
+		if ((ctx->digcnt + ctx->bufcnt + ctx->total) < 9) {
+			/*
+			* OMAP HW accel works only with buffers >= 9
+			* will switch to bypass in final()
+			* final has the same request and data
+			*/
+			omap_sham_append_sg(ctx);
+			return 0;
+		} else if (ctx->bufcnt + ctx->total <= 64) {
+			ctx->flags |= FLAGS_CPU;
+		} else if (!ctx->bufcnt && sg_is_last(ctx->sg)) {
+			/* may be can use faster functions */
+			int aligned = IS_ALIGNED((u32)ctx->sg->offset,
+								sizeof(u32));
+
+			if (aligned && (ctx->flags & FLAGS_FIRST))
+				/* digest: first and final */
+				ctx->flags |= FLAGS_FAST;
+
+			ctx->flags &= ~FLAGS_FIRST;
+		}
+	} else if (ctx->bufcnt + ctx->total <= ctx->buflen) {
+		/* if not finaup -> not fast */
+		omap_sham_append_sg(ctx);
+		return 0;
+	}
+
+	return omap_sham_enqueue(req, OP_UPDATE);
+}
+
+static int omap_sham_shash_digest(struct crypto_shash *shash, u32 flags,
+				  const u8 *data, unsigned int len, u8 *out)
+{
+	struct {
+		struct shash_desc shash;
+		char ctx[crypto_shash_descsize(shash)];
+	} desc;
+
+	desc.shash.tfm = shash;
+	desc.shash.flags = flags & CRYPTO_TFM_REQ_MAY_SLEEP;
+
+	return crypto_shash_digest(&desc.shash, data, len, out);
+}
+
+static int omap_sham_final_shash(struct ahash_request *req)
+{
+	struct omap_sham_ctx *tctx = crypto_tfm_ctx(req->base.tfm);
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
+
+	return omap_sham_shash_digest(tctx->fallback, req->base.flags,
+				      ctx->buffer, ctx->bufcnt, req->result);
+}
+
+static int omap_sham_final(struct ahash_request *req)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
+	int err = 0;
+
+	ctx->flags |= FLAGS_FINUP;
+
+	/* OMAP HW accel works only with buffers >= 9 */
+	/* HMAC is always >= 9 because of ipad */
+	if ((ctx->digcnt + ctx->bufcnt) < 9)
+		err = omap_sham_final_shash(req);
+	else if (ctx->bufcnt)
+		return omap_sham_enqueue(req, OP_FINAL);
+
+	omap_sham_cleanup(req);
+
+	return err;
+}
+
+static int omap_sham_finup(struct ahash_request *req)
+{
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
+	int err1, err2;
+
+	ctx->flags |= FLAGS_FINUP;
+
+	err1 = omap_sham_update(req);
+	if (err1 == -EINPROGRESS)
+		return err1;
+	/*
+	 * final() has to be always called to cleanup resources
+	 * even if udpate() failed, except EINPROGRESS
+	 */
+	err2 = omap_sham_final(req);
+
+	return err1 ?: err2;
+}
+
+static int omap_sham_digest(struct ahash_request *req)
+{
+	return omap_sham_init(req) ?: omap_sham_finup(req);
+}
+
+static int omap_sham_setkey(struct crypto_ahash *tfm, const u8 *key,
+		      unsigned int keylen)
+{
+	struct omap_sham_ctx *tctx = crypto_ahash_ctx(tfm);
+	struct omap_sham_hmac_ctx *bctx = tctx->base;
+	int bs = crypto_shash_blocksize(bctx->shash);
+	int ds = crypto_shash_digestsize(bctx->shash);
+	int err, i;
+	err = crypto_shash_setkey(tctx->fallback, key, keylen);
+	if (err)
+		return err;
+
+	if (keylen > bs) {
+		err = omap_sham_shash_digest(bctx->shash,
+				crypto_shash_get_flags(bctx->shash),
+				key, keylen, bctx->ipad);
+		if (err)
+			return err;
+		keylen = ds;
+	} else {
+		memcpy(bctx->ipad, key, keylen);
+	}
+
+	memset(bctx->ipad + keylen, 0, bs - keylen);
+	memcpy(bctx->opad, bctx->ipad, bs);
+
+	for (i = 0; i < bs; i++) {
+		bctx->ipad[i] ^= 0x36;
+		bctx->opad[i] ^= 0x5c;
+	}
+
+	return err;
+}
+
+static int omap_sham_cra_init_alg(struct crypto_tfm *tfm, const char *alg_base)
+{
+	struct omap_sham_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("omap-sham: 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 omap_sham_reqctx));
+
+	if (alg_base) {
+		struct omap_sham_hmac_ctx *bctx = tctx->base;
+		tctx->flags |= FLAGS_HMAC;
+		bctx->shash = crypto_alloc_shash(alg_base, 0,
+						CRYPTO_ALG_NEED_FALLBACK);
+		if (IS_ERR(bctx->shash)) {
+			pr_err("omap-sham: base driver '%s' "
+					"could not be loaded.\n", alg_base);
+			crypto_free_shash(tctx->fallback);
+			return PTR_ERR(bctx->shash);
+		}
+
+	}
+
+	return 0;
+}
+
+static int omap_sham_cra_init(struct crypto_tfm *tfm)
+{
+	return omap_sham_cra_init_alg(tfm, NULL);
+}
+
+static int omap_sham_cra_sha1_init(struct crypto_tfm *tfm)
+{
+	return omap_sham_cra_init_alg(tfm, "sha1");
+}
+
+static int omap_sham_cra_md5_init(struct crypto_tfm *tfm)
+{
+	return omap_sham_cra_init_alg(tfm, "md5");
+}
+
+static void omap_sham_cra_exit(struct crypto_tfm *tfm)
+{
+	struct omap_sham_ctx *tctx = crypto_tfm_ctx(tfm);
+
+	crypto_free_shash(tctx->fallback);
+	tctx->fallback = NULL;
+
+	if (tctx->flags & FLAGS_HMAC) {
+		struct omap_sham_hmac_ctx *bctx = tctx->base;
+		crypto_free_shash(bctx->shash);
+	}
+}
+
+static struct ahash_alg algs[] = {
+{
+	.init		= omap_sham_init,
+	.update		= omap_sham_update,
+	.final		= omap_sham_final,
+	.finup		= omap_sham_finup,
+	.digest		= omap_sham_digest,
+	.halg.digestsize	= SHA1_DIGEST_SIZE,
+	.halg.base	= {
+		.cra_name		= "sha1",
+		.cra_driver_name	= "omap-sha1",
+		.cra_priority		= 100,
+		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
+						CRYPTO_ALG_ASYNC |
+						CRYPTO_ALG_NEED_FALLBACK,
+		.cra_blocksize		= SHA1_BLOCK_SIZE,
+		.cra_ctxsize		= sizeof(struct omap_sham_ctx),
+		.cra_alignmask		= 0,
+		.cra_module		= THIS_MODULE,
+		.cra_init		= omap_sham_cra_init,
+		.cra_exit		= omap_sham_cra_exit,
+	}
+},
+{
+	.init		= omap_sham_init,
+	.update		= omap_sham_update,
+	.final		= omap_sham_final,
+	.finup		= omap_sham_finup,
+	.digest		= omap_sham_digest,
+	.halg.digestsize	= MD5_DIGEST_SIZE,
+	.halg.base	= {
+		.cra_name		= "md5",
+		.cra_driver_name	= "omap-md5",
+		.cra_priority		= 100,
+		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
+						CRYPTO_ALG_ASYNC |
+						CRYPTO_ALG_NEED_FALLBACK,
+		.cra_blocksize		= SHA1_BLOCK_SIZE,
+		.cra_ctxsize		= sizeof(struct omap_sham_ctx),
+		.cra_alignmask		= 0,
+		.cra_module		= THIS_MODULE,
+		.cra_init		= omap_sham_cra_init,
+		.cra_exit		= omap_sham_cra_exit,
+	}
+},
+{
+	.init		= omap_sham_init,
+	.update		= omap_sham_update,
+	.final		= omap_sham_final,
+	.finup		= omap_sham_finup,
+	.digest		= omap_sham_digest,
+	.setkey		= omap_sham_setkey,
+	.halg.digestsize	= SHA1_DIGEST_SIZE,
+	.halg.base	= {
+		.cra_name		= "hmac(sha1)",
+		.cra_driver_name	= "omap-hmac-sha1",
+		.cra_priority		= 100,
+		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
+						CRYPTO_ALG_ASYNC |
+						CRYPTO_ALG_NEED_FALLBACK,
+		.cra_blocksize		= SHA1_BLOCK_SIZE,
+		.cra_ctxsize		= sizeof(struct omap_sham_ctx) +
+					sizeof(struct omap_sham_hmac_ctx),
+		.cra_alignmask		= 0,
+		.cra_module		= THIS_MODULE,
+		.cra_init		= omap_sham_cra_sha1_init,
+		.cra_exit		= omap_sham_cra_exit,
+	}
+},
+{
+	.init		= omap_sham_init,
+	.update		= omap_sham_update,
+	.final		= omap_sham_final,
+	.finup		= omap_sham_finup,
+	.digest		= omap_sham_digest,
+	.setkey		= omap_sham_setkey,
+	.halg.digestsize	= MD5_DIGEST_SIZE,
+	.halg.base	= {
+		.cra_name		= "hmac(md5)",
+		.cra_driver_name	= "omap-hmac-md5",
+		.cra_priority		= 100,
+		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
+						CRYPTO_ALG_ASYNC |
+						CRYPTO_ALG_NEED_FALLBACK,
+		.cra_blocksize		= SHA1_BLOCK_SIZE,
+		.cra_ctxsize		= sizeof(struct omap_sham_ctx) +
+					sizeof(struct omap_sham_hmac_ctx),
+		.cra_alignmask		= 0,
+		.cra_module		= THIS_MODULE,
+		.cra_init		= omap_sham_cra_md5_init,
+		.cra_exit		= omap_sham_cra_exit,
+	}
+}
+};
+
+static void omap_sham_done_task(unsigned long data)
+{
+	struct omap_sham_dev *dd = (struct omap_sham_dev *)data;
+	struct ahash_request *req = dd->req;
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
+	int ready = 1;
+
+	if (ctx->flags & FLAGS_OUTPUT_READY) {
+		ctx->flags &= ~FLAGS_OUTPUT_READY;
+		ready = 1;
+	}
+
+	if (dd->flags & FLAGS_DMA_ACTIVE) {
+		dd->flags &= ~FLAGS_DMA_ACTIVE;
+		omap_sham_update_dma_stop(dd);
+		omap_sham_update_dma_slow(dd);
+	}
+
+	if (ready && !(dd->flags & FLAGS_DMA_ACTIVE)) {
+		dev_dbg(dd->dev, "update done\n");
+		/* finish curent request */
+		omap_sham_finish_req(req, 0);
+		/* start new request */
+		omap_sham_handle_queue(dd);
+	}
+}
+
+static void omap_sham_queue_task(unsigned long data)
+{
+	struct omap_sham_dev *dd = (struct omap_sham_dev *)data;
+
+	omap_sham_handle_queue(dd);
+}
+
+static irqreturn_t omap_sham_irq(int irq, void *dev_id)
+{
+	struct omap_sham_dev *dd = dev_id;
+	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
+
+	if (!ctx) {
+		dev_err(dd->dev, "unknown interrupt.\n");
+		return IRQ_HANDLED;
+	}
+
+	if (unlikely(ctx->flags & FLAGS_FINAL))
+		/* final -> allow device to go to power-saving mode */
+		omap_sham_write_mask(dd, SHA_REG_CTRL, 0, SHA_REG_CTRL_LENGTH);
+
+	omap_sham_write_mask(dd, SHA_REG_CTRL, SHA_REG_CTRL_OUTPUT_READY,
+				 SHA_REG_CTRL_OUTPUT_READY);
+	omap_sham_read(dd, SHA_REG_CTRL);
+
+	ctx->flags |= FLAGS_OUTPUT_READY;
+	tasklet_schedule(&dd->done_task);
+
+	return IRQ_HANDLED;
+}
+
+static void omap_sham_dma_callback(int lch, u16 ch_status, void *data)
+{
+	struct omap_sham_dev *dd = data;
+
+	if (likely(lch == dd->dma_lch))
+		tasklet_schedule(&dd->done_task);
+}
+
+static int omap_sham_dma_init(struct omap_sham_dev *dd)
+{
+	int err;
+
+	dd->dma_lch = -1;
+
+	err = omap_request_dma(dd->dma, dev_name(dd->dev),
+			omap_sham_dma_callback, dd, &dd->dma_lch);
+	if (err) {
+		dev_err(dd->dev, "Unable to request DMA channel\n");
+		return err;
+	}
+	omap_set_dma_dest_params(dd->dma_lch, 0,
+			OMAP_DMA_AMODE_CONSTANT,
+			dd->phys_base + SHA_REG_DIN(0), 0, 16);
+
+	omap_set_dma_dest_burst_mode(dd->dma_lch,
+			OMAP_DMA_DATA_BURST_16);
+
+	return 0;
+}
+
+static void omap_sham_dma_cleanup(struct omap_sham_dev *dd)
+{
+	if (dd->dma_lch >= 0) {
+		omap_free_dma(dd->dma_lch);
+		dd->dma_lch = -1;
+	}
+}
+
+static int __devinit omap_sham_probe(struct platform_device *pdev)
+{
+	struct omap_sham_dev *dd;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+	int err, i, j;
+
+	dd = kzalloc(sizeof(struct omap_sham_dev), GFP_KERNEL);
+	if (dd == NULL) {
+		dev_err(dev, "unable to alloc data struct.\n");
+		err = -ENOMEM;
+		goto data_err;
+	}
+	dd->dev = dev;
+	platform_set_drvdata(pdev, dd);
+
+	INIT_LIST_HEAD(&dd->list);
+	spin_lock_init(&dd->lock);
+	tasklet_init(&dd->done_task, omap_sham_done_task, (unsigned long)dd);
+	tasklet_init(&dd->queue_task, omap_sham_queue_task, (unsigned long)dd);
+	crypto_init_queue(&dd->queue, OMAP_SHAM_QUEUE_LENGTH);
+
+	dd->irq = -1;
+
+	/* Get the base address */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(dev, "no MEM resource info\n");
+		err = -ENODEV;
+		goto res_err;
+	}
+	dd->phys_base = res->start;
+
+	/* Get the DMA */
+	res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+	if (!res) {
+		dev_err(dev, "no DMA resource info\n");
+		err = -ENODEV;
+		goto res_err;
+	}
+	dd->dma = res->start;
+
+	/* Get the IRQ */
+	dd->irq = platform_get_irq(pdev,  0);
+	if (dd->irq < 0) {
+		dev_err(dev, "no IRQ resource info\n");
+		err = dd->irq;
+		goto res_err;
+	}
+
+	err = request_irq(dd->irq, omap_sham_irq,
+			IRQF_TRIGGER_LOW, dev_name(dev), dd);
+	if (err) {
+		dev_err(dev, "unable to request irq.\n");
+		goto res_err;
+	}
+
+	err = omap_sham_dma_init(dd);
+	if (err)
+		goto dma_err;
+
+	/* Initializing the clock */
+	dd->iclk = clk_get(dev, "ick");
+	if (!dd->iclk) {
+		dev_err(dev, "clock intialization failed.\n");
+		err = -ENODEV;
+		goto clk_err;
+	}
+
+	dd->io_base = ioremap(dd->phys_base, SZ_4K);
+	if (!dd->io_base) {
+		dev_err(dev, "can't ioremap\n");
+		err = -ENOMEM;
+		goto io_err;
+	}
+
+	clk_enable(dd->iclk);
+	dev_info(dev, "hw accel on OMAP rev %u.%u\n",
+		(omap_sham_read(dd, SHA_REG_REV) & SHA_REG_REV_MAJOR) >> 4,
+		omap_sham_read(dd, SHA_REG_REV) & SHA_REG_REV_MINOR);
+	clk_disable(dd->iclk);
+
+	spin_lock(&sham.lock);
+	list_add_tail(&dd->list, &sham.dev_list);
+	spin_unlock(&sham.lock);
+
+	for (i = 0; i < ARRAY_SIZE(algs); i++) {
+		err = crypto_register_ahash(&algs[i]);
+		if (err)
+			goto err_algs;
+	}
+
+	return 0;
+
+err_algs:
+	for (j = 0; j < i; j++)
+		crypto_unregister_ahash(&algs[j]);
+	iounmap(dd->io_base);
+io_err:
+	clk_put(dd->iclk);
+clk_err:
+	omap_sham_dma_cleanup(dd);
+dma_err:
+	if (dd->irq >= 0)
+		free_irq(dd->irq, dd);
+res_err:
+	kfree(dd);
+	dd = NULL;
+data_err:
+	dev_err(dev, "initialization failed.\n");
+
+	return err;
+}
+
+static int __devexit omap_sham_remove(struct platform_device *pdev)
+{
+	static struct omap_sham_dev *dd;
+	int i;
+
+	dd = platform_get_drvdata(pdev);
+	if (!dd)
+		return -ENODEV;
+	spin_lock(&sham.lock);
+	list_del(&dd->list);
+	spin_unlock(&sham.lock);
+	for (i = 0; i < ARRAY_SIZE(algs); i++)
+		crypto_unregister_ahash(&algs[i]);
+	tasklet_kill(&dd->done_task);
+	tasklet_kill(&dd->queue_task);
+	iounmap(dd->io_base);
+	clk_put(dd->iclk);
+	omap_sham_dma_cleanup(dd);
+	if (dd->irq >= 0)
+		free_irq(dd->irq, dd);
+	kfree(dd);
+	dd = NULL;
+
+	return 0;
+}
+
+static struct platform_driver omap_sham_driver = {
+	.probe	= omap_sham_probe,
+	.remove	= omap_sham_remove,
+	.driver	= {
+		.name	= "omap-sham",
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init omap_sham_mod_init(void)
+{
+	pr_info("loading %s driver\n", "omap-sham");
+
+	if (!cpu_class_is_omap2() ||
+		omap_type() != OMAP2_DEVICE_TYPE_SEC) {
+		pr_err("Unsupported cpu\n");
+		return -ENODEV;
+	}
+
+	return platform_driver_register(&omap_sham_driver);
+}
+
+static void __exit omap_sham_mod_exit(void)
+{
+	platform_driver_unregister(&omap_sham_driver);
+}
+
+module_init(omap_sham_mod_init);
+module_exit(omap_sham_mod_exit);
+
+MODULE_DESCRIPTION("OMAP SHA1/MD5 hw acceleration support.");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Dmitry Kasatkin");