[PATCH 07/24] crypto: atmel-aes: change atmel_aes_write_ctrl() signature

From: Cyrille Pitchen
Date: Thu Dec 17 2015 - 11:50:44 EST


This patch changes the signature of atmel_aes_write_ctrl() to make it more
generic. This will be used by future patches when implementing new block
cipher modes such as GCM.

Especially atmel_aes_hw_init() is now called outside
atmel_aes_write_ctrl(): this allows to call atmel_aes_write_ctrl() many
times, still initializing the hardware only once.

Indeed, the support of GCM will require to update the Mode Register and
the IV when processing a single request.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxx>
---
drivers/crypto/atmel-aes.c | 24 ++++++++++--------------
1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/drivers/crypto/atmel-aes.c b/drivers/crypto/atmel-aes.c
index 9a9e1b88a384..ccb8a8322bf7 100644
--- a/drivers/crypto/atmel-aes.c
+++ b/drivers/crypto/atmel-aes.c
@@ -496,16 +496,11 @@ static int atmel_aes_crypt_dma_start(struct atmel_aes_dev *dd)
return err;
}

-static int atmel_aes_write_ctrl(struct atmel_aes_dev *dd)
+static void atmel_aes_write_ctrl(struct atmel_aes_dev *dd, bool use_dma,
+ const u32 *iv)
{
- int err;
u32 valcr = 0, valmr = 0;

- err = atmel_aes_hw_init(dd);
-
- if (err)
- return err;
-
/* MR register must be set before IV registers */
if (dd->ctx->keylen == AES_KEYSIZE_128)
valmr |= AES_MR_KEYSIZE_128;
@@ -539,7 +534,7 @@ static int atmel_aes_write_ctrl(struct atmel_aes_dev *dd)
if (dd->flags & AES_FLAGS_ENCRYPT)
valmr |= AES_MR_CYPHER_ENC;

- if (dd->total > ATMEL_AES_DMA_THRESHOLD) {
+ if (use_dma) {
valmr |= AES_MR_SMOD_IDATAR0;
if (dd->caps.has_dualbuff)
valmr |= AES_MR_DUALBUFF;
@@ -555,11 +550,9 @@ static int atmel_aes_write_ctrl(struct atmel_aes_dev *dd)

if (((dd->flags & AES_FLAGS_CBC) || (dd->flags & AES_FLAGS_CFB) ||
(dd->flags & AES_FLAGS_OFB) || (dd->flags & AES_FLAGS_CTR)) &&
- dd->req->info) {
- atmel_aes_write_n(dd, AES_IVR(0), dd->req->info, 4);
+ iv) {
+ atmel_aes_write_n(dd, AES_IVR(0), iv, 4);
}
-
- return 0;
}

static int atmel_aes_handle_queue(struct atmel_aes_dev *dd,
@@ -570,6 +563,7 @@ static int atmel_aes_handle_queue(struct atmel_aes_dev *dd,
struct atmel_aes_reqctx *rctx;
unsigned long flags;
int err, ret = 0;
+ bool use_dma;

spin_lock_irqsave(&dd->lock, flags);
if (req)
@@ -607,9 +601,11 @@ static int atmel_aes_handle_queue(struct atmel_aes_dev *dd,
dd->ctx = ctx;
ctx->dd = dd;

- err = atmel_aes_write_ctrl(dd);
+ err = atmel_aes_hw_init(dd);
if (!err) {
- if (dd->total > ATMEL_AES_DMA_THRESHOLD)
+ use_dma = (dd->total > ATMEL_AES_DMA_THRESHOLD);
+ atmel_aes_write_ctrl(dd, use_dma, req->info);
+ if (use_dma)
err = atmel_aes_crypt_dma_start(dd);
else
err = atmel_aes_crypt_cpu_start(dd);
--
1.8.2.2

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