[PATCHv2 4/6] omap-aes: unnecessary code removed

Dmitry Kasatkin
2010-11-30T08:13:04Z

Key and IV should always be set before AES operation.
So no need to check if it has changed or not.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com>
---
drivers/crypto/omap-aes.c | 70 +++++++++++----------------------------------
1 files changed, 17 insertions(+), 53 deletions(-)

diff --git a/drivers/crypto/omap-aes.c b/drivers/crypto/omap-aes.c
index 704cc70..0b21dce 100644
--- a/drivers/crypto/omap-aes.c
+++ b/drivers/crypto/omap-aes.c
@@ -74,11 +74,9 @@
#define FLAGS_CBC BIT(1)
#define FLAGS_GIV BIT(2)

-#define FLAGS_NEW_KEY BIT(4)
-#define FLAGS_NEW_IV BIT(5)
-#define FLAGS_INIT BIT(6)
-#define FLAGS_FAST BIT(7)
-#define FLAGS_BUSY BIT(8)
+#define FLAGS_INIT BIT(4)
+#define FLAGS_FAST BIT(5)
+#define FLAGS_BUSY BIT(6)

struct omap_aes_ctx {
struct omap_aes_dev *dd;
@@ -105,9 +103,6 @@ struct omap_aes_dev {
unsigned long flags;
int err;

- u32 *iv;
- u32 ctrl;
-
spinlock_t lock;
struct crypto_queue queue;

@@ -209,28 +204,13 @@ static int omap_aes_hw_init(struct omap_aes_dev *dd)
static int omap_aes_write_ctrl(struct omap_aes_dev *dd)
{
unsigned int key32;
- int i, err, init = dd->flags & FLAGS_INIT;
+ int i, err;
u32 val, mask;

err = omap_aes_hw_init(dd);
if (err)
return err;

- val = FLD_VAL(((dd->ctx->keylen >> 3) - 1), 4, 3);
- if (dd->flags & FLAGS_CBC)
- val |= AES_REG_CTRL_CBC;
- if (dd->flags & FLAGS_ENCRYPT)
- val |= AES_REG_CTRL_DIRECTION;
-
- /* check if hw state & mode have not changed */
- if (init && dd->ctrl == val && !(dd->flags & FLAGS_NEW_IV) &&
- !(dd->ctx->flags & FLAGS_NEW_KEY))
- goto out;
-
- /* only need to write control registers for new settings */
-
- dd->ctrl = val;
-
val = 0;
if (dd->dma_lch_out >= 0)
val |= AES_REG_MASK_DMA_OUT_EN;
@@ -241,27 +221,28 @@ static int omap_aes_write_ctrl(struct omap_aes_dev *dd)

omap_aes_write_mask(dd, AES_REG_MASK, val, mask);

- pr_debug("Set key\n");
key32 = dd->ctx->keylen / sizeof(u32);
- /* set a key */
+
+ /* it seems a key should always be set even if it has not changed */
for (i = 0; i < key32; i++) {
omap_aes_write(dd, AES_REG_KEY(i),
__le32_to_cpu(dd->ctx->key[i]));
}
- dd->ctx->flags &= ~FLAGS_NEW_KEY;

- if (dd->flags & FLAGS_NEW_IV) {
- pr_debug("Set IV\n");
- omap_aes_write_n(dd, AES_REG_IV(0), dd->iv, 4);
- dd->flags &= ~FLAGS_NEW_IV;
- }
+ if ((dd->flags & FLAGS_CBC) && dd->req->info)
+ omap_aes_write_n(dd, AES_REG_IV(0), dd->req->info, 4);
+
+ val = FLD_VAL(((dd->ctx->keylen >> 3) - 1), 4, 3);
+ if (dd->flags & FLAGS_CBC)
+ val |= AES_REG_CTRL_CBC;
+ if (dd->flags & FLAGS_ENCRYPT)
+ val |= AES_REG_CTRL_DIRECTION;

mask = AES_REG_CTRL_CBC | AES_REG_CTRL_DIRECTION |
AES_REG_CTRL_KEY_SIZE;

- omap_aes_write_mask(dd, AES_REG_CTRL, dd->ctrl, mask);
+ omap_aes_write_mask(dd, AES_REG_CTRL, val, mask);

-out:
/* start DMA or disable idle mode */
omap_aes_write_mask(dd, AES_REG_MASK, AES_REG_MASK_START,
AES_REG_MASK_START);
@@ -561,16 +542,12 @@ static int omap_aes_crypt_dma_start(struct omap_aes_dev *dd)
static void omap_aes_finish_req(struct omap_aes_dev *dd, int err)
{
struct ablkcipher_request *req = dd->req;
- struct omap_aes_ctx *ctx;

pr_debug("err: %d\n", err);

dd->flags &= ~FLAGS_BUSY;

- ctx = crypto_ablkcipher_ctx(crypto_ablkcipher_reqtfm(req));
-
- if (req->base.complete)
- req->base.complete(&req->base, err);
+ req->base.complete(&req->base, err);
}

static int omap_aes_crypt_dma_stop(struct omap_aes_dev *dd)
@@ -636,8 +613,6 @@ static int omap_aes_handle_queue(struct omap_aes_dev *dd,

req = ablkcipher_request_cast(async_req);

- pr_debug("get new req\n");
-
/* assign new request to device */
dd->req = req;
dd->total = req->nbytes;
@@ -651,18 +626,8 @@ static int omap_aes_handle_queue(struct omap_aes_dev *dd,
rctx->mode &= FLAGS_MODE_MASK;
dd->flags = (dd->flags & ~FLAGS_MODE_MASK) | rctx->mode;

- dd->iv = req->info;
- if ((dd->flags & FLAGS_CBC) && dd->iv)
- dd->flags |= FLAGS_NEW_IV;
- else
- dd->flags &= ~FLAGS_NEW_IV;
-
+ dd->ctx = ctx;
ctx->dd = dd;
- if (dd->ctx != ctx) {
- /* assign new context to device */
- dd->ctx = ctx;
- ctx->flags |= FLAGS_NEW_KEY;
- }

err = omap_aes_crypt_dma_start(dd);
if (err) {
@@ -744,7 +709,6 @@ static int omap_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,

memcpy(ctx->key, key, keylen);
ctx->keylen = keylen;
- ctx->flags |= FLAGS_NEW_KEY;

return 0;
}
--
1.7.0.4