kernel_optimize_test/drivers/crypto/tegra-aes.c
Linus Walleij f5b38c5f19 crypto: tegra - use kernel entropy instead of ad-hoc
The way I read the Tegra AES RNG is that it has a homebrew
algorithm for initializing the 128bit RNG using timespec and
the unique chip ID. This looks like reinventing the (square)
wheel, instead just grab 128bits from the kernel entropy pool
where the time and (after another patch) chip unique ID is
already mixed in.

Incidentally this also gets rid of a rather ugly
cross-dependence on the machine using an extern declaration.

Cc: Varun Wadekar <vwadekar@nvidia.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: linux-tegra@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-09-13 21:43:53 +10:00

1089 lines
27 KiB
C

/*
* drivers/crypto/tegra-aes.c
*
* Driver for NVIDIA Tegra AES hardware engine residing inside the
* Bit Stream Engine for Video (BSEV) hardware block.
*
* The programming sequence for this engine is with the help
* of commands which travel via a command queue residing between the
* CPU and the BSEV block. The BSEV engine has an internal RAM (VRAM)
* where the final input plaintext, keys and the IV have to be copied
* before starting the encrypt/decrypt operation.
*
* Copyright (c) 2010, NVIDIA Corporation.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/mutex.h>
#include <linux/interrupt.h>
#include <linux/completion.h>
#include <linux/workqueue.h>
#include <crypto/scatterwalk.h>
#include <crypto/aes.h>
#include <crypto/internal/rng.h>
#include "tegra-aes.h"
#define FLAGS_MODE_MASK 0x00FF
#define FLAGS_ENCRYPT BIT(0)
#define FLAGS_CBC BIT(1)
#define FLAGS_GIV BIT(2)
#define FLAGS_RNG BIT(3)
#define FLAGS_OFB BIT(4)
#define FLAGS_NEW_KEY BIT(5)
#define FLAGS_NEW_IV BIT(6)
#define FLAGS_INIT BIT(7)
#define FLAGS_FAST BIT(8)
#define FLAGS_BUSY 9
/*
* Defines AES engine Max process bytes size in one go, which takes 1 msec.
* AES engine spends about 176 cycles/16-bytes or 11 cycles/byte
* The duration CPU can use the BSE to 1 msec, then the number of available
* cycles of AVP/BSE is 216K. In this duration, AES can process 216/11 ~= 19KB
* Based on this AES_HW_DMA_BUFFER_SIZE_BYTES is configured to 16KB.
*/
#define AES_HW_DMA_BUFFER_SIZE_BYTES 0x4000
/*
* The key table length is 64 bytes
* (This includes first upto 32 bytes key + 16 bytes original initial vector
* and 16 bytes updated initial vector)
*/
#define AES_HW_KEY_TABLE_LENGTH_BYTES 64
/*
* The memory being used is divides as follows:
* 1. Key - 32 bytes
* 2. Original IV - 16 bytes
* 3. Updated IV - 16 bytes
* 4. Key schedule - 256 bytes
*
* 1+2+3 constitute the hw key table.
*/
#define AES_HW_IV_SIZE 16
#define AES_HW_KEYSCHEDULE_LEN 256
#define AES_IVKEY_SIZE (AES_HW_KEY_TABLE_LENGTH_BYTES + AES_HW_KEYSCHEDULE_LEN)
/* Define commands required for AES operation */
enum {
CMD_BLKSTARTENGINE = 0x0E,
CMD_DMASETUP = 0x10,
CMD_DMACOMPLETE = 0x11,
CMD_SETTABLE = 0x15,
CMD_MEMDMAVD = 0x22,
};
/* Define sub-commands */
enum {
SUBCMD_VRAM_SEL = 0x1,
SUBCMD_CRYPTO_TABLE_SEL = 0x3,
SUBCMD_KEY_TABLE_SEL = 0x8,
};
/* memdma_vd command */
#define MEMDMA_DIR_DTOVRAM 0 /* sdram -> vram */
#define MEMDMA_DIR_VTODRAM 1 /* vram -> sdram */
#define MEMDMA_DIR_SHIFT 25
#define MEMDMA_NUM_WORDS_SHIFT 12
/* command queue bit shifts */
enum {
CMDQ_KEYTABLEADDR_SHIFT = 0,
CMDQ_KEYTABLEID_SHIFT = 17,
CMDQ_VRAMSEL_SHIFT = 23,
CMDQ_TABLESEL_SHIFT = 24,
CMDQ_OPCODE_SHIFT = 26,
};
/*
* The secure key slot contains a unique secure key generated
* and loaded by the bootloader. This slot is marked as non-accessible
* to the kernel.
*/
#define SSK_SLOT_NUM 4
#define AES_NR_KEYSLOTS 8
#define TEGRA_AES_QUEUE_LENGTH 50
#define DEFAULT_RNG_BLK_SZ 16
/* The command queue depth */
#define AES_HW_MAX_ICQ_LENGTH 5
struct tegra_aes_slot {
struct list_head node;
int slot_num;
};
static struct tegra_aes_slot ssk = {
.slot_num = SSK_SLOT_NUM,
};
struct tegra_aes_reqctx {
unsigned long mode;
};
struct tegra_aes_dev {
struct device *dev;
void __iomem *io_base;
dma_addr_t ivkey_phys_base;
void __iomem *ivkey_base;
struct clk *aes_clk;
struct tegra_aes_ctx *ctx;
int irq;
unsigned long flags;
struct completion op_complete;
u32 *buf_in;
dma_addr_t dma_buf_in;
u32 *buf_out;
dma_addr_t dma_buf_out;
u8 *iv;
u8 dt[DEFAULT_RNG_BLK_SZ];
int ivlen;
u64 ctr;
spinlock_t lock;
struct crypto_queue queue;
struct tegra_aes_slot *slots;
struct ablkcipher_request *req;
size_t total;
struct scatterlist *in_sg;
size_t in_offset;
struct scatterlist *out_sg;
size_t out_offset;
};
static struct tegra_aes_dev *aes_dev;
struct tegra_aes_ctx {
struct tegra_aes_dev *dd;
unsigned long flags;
struct tegra_aes_slot *slot;
u8 key[AES_MAX_KEY_SIZE];
size_t keylen;
};
static struct tegra_aes_ctx rng_ctx = {
.flags = FLAGS_NEW_KEY,
.keylen = AES_KEYSIZE_128,
};
/* keep registered devices data here */
static struct list_head dev_list;
static DEFINE_SPINLOCK(list_lock);
static DEFINE_MUTEX(aes_lock);
static void aes_workqueue_handler(struct work_struct *work);
static DECLARE_WORK(aes_work, aes_workqueue_handler);
static struct workqueue_struct *aes_wq;
static inline u32 aes_readl(struct tegra_aes_dev *dd, u32 offset)
{
return readl(dd->io_base + offset);
}
static inline void aes_writel(struct tegra_aes_dev *dd, u32 val, u32 offset)
{
writel(val, dd->io_base + offset);
}
static int aes_start_crypt(struct tegra_aes_dev *dd, u32 in_addr, u32 out_addr,
int nblocks, int mode, bool upd_iv)
{
u32 cmdq[AES_HW_MAX_ICQ_LENGTH];
int i, eng_busy, icq_empty, ret;
u32 value;
/* reset all the interrupt bits */
aes_writel(dd, 0xFFFFFFFF, TEGRA_AES_INTR_STATUS);
/* enable error, dma xfer complete interrupts */
aes_writel(dd, 0x33, TEGRA_AES_INT_ENB);
cmdq[0] = CMD_DMASETUP << CMDQ_OPCODE_SHIFT;
cmdq[1] = in_addr;
cmdq[2] = CMD_BLKSTARTENGINE << CMDQ_OPCODE_SHIFT | (nblocks-1);
cmdq[3] = CMD_DMACOMPLETE << CMDQ_OPCODE_SHIFT;
value = aes_readl(dd, TEGRA_AES_CMDQUE_CONTROL);
/* access SDRAM through AHB */
value &= ~TEGRA_AES_CMDQ_CTRL_SRC_STM_SEL_FIELD;
value &= ~TEGRA_AES_CMDQ_CTRL_DST_STM_SEL_FIELD;
value |= TEGRA_AES_CMDQ_CTRL_SRC_STM_SEL_FIELD |
TEGRA_AES_CMDQ_CTRL_DST_STM_SEL_FIELD |
TEGRA_AES_CMDQ_CTRL_ICMDQEN_FIELD;
aes_writel(dd, value, TEGRA_AES_CMDQUE_CONTROL);
dev_dbg(dd->dev, "cmd_q_ctrl=0x%x", value);
value = (0x1 << TEGRA_AES_SECURE_INPUT_ALG_SEL_SHIFT) |
((dd->ctx->keylen * 8) <<
TEGRA_AES_SECURE_INPUT_KEY_LEN_SHIFT) |
((u32)upd_iv << TEGRA_AES_SECURE_IV_SELECT_SHIFT);
if (mode & FLAGS_CBC) {
value |= ((((mode & FLAGS_ENCRYPT) ? 2 : 3)
<< TEGRA_AES_SECURE_XOR_POS_SHIFT) |
(((mode & FLAGS_ENCRYPT) ? 2 : 3)
<< TEGRA_AES_SECURE_VCTRAM_SEL_SHIFT) |
((mode & FLAGS_ENCRYPT) ? 1 : 0)
<< TEGRA_AES_SECURE_CORE_SEL_SHIFT);
} else if (mode & FLAGS_OFB) {
value |= ((TEGRA_AES_SECURE_XOR_POS_FIELD) |
(2 << TEGRA_AES_SECURE_INPUT_SEL_SHIFT) |
(TEGRA_AES_SECURE_CORE_SEL_FIELD));
} else if (mode & FLAGS_RNG) {
value |= (((mode & FLAGS_ENCRYPT) ? 1 : 0)
<< TEGRA_AES_SECURE_CORE_SEL_SHIFT |
TEGRA_AES_SECURE_RNG_ENB_FIELD);
} else {
value |= (((mode & FLAGS_ENCRYPT) ? 1 : 0)
<< TEGRA_AES_SECURE_CORE_SEL_SHIFT);
}
dev_dbg(dd->dev, "secure_in_sel=0x%x", value);
aes_writel(dd, value, TEGRA_AES_SECURE_INPUT_SELECT);
aes_writel(dd, out_addr, TEGRA_AES_SECURE_DEST_ADDR);
INIT_COMPLETION(dd->op_complete);
for (i = 0; i < AES_HW_MAX_ICQ_LENGTH - 1; i++) {
do {
value = aes_readl(dd, TEGRA_AES_INTR_STATUS);
eng_busy = value & TEGRA_AES_ENGINE_BUSY_FIELD;
icq_empty = value & TEGRA_AES_ICQ_EMPTY_FIELD;
} while (eng_busy && !icq_empty);
aes_writel(dd, cmdq[i], TEGRA_AES_ICMDQUE_WR);
}
ret = wait_for_completion_timeout(&dd->op_complete,
msecs_to_jiffies(150));
if (ret == 0) {
dev_err(dd->dev, "timed out (0x%x)\n",
aes_readl(dd, TEGRA_AES_INTR_STATUS));
return -ETIMEDOUT;
}
aes_writel(dd, cmdq[AES_HW_MAX_ICQ_LENGTH - 1], TEGRA_AES_ICMDQUE_WR);
return 0;
}
static void aes_release_key_slot(struct tegra_aes_slot *slot)
{
if (slot->slot_num == SSK_SLOT_NUM)
return;
spin_lock(&list_lock);
list_add_tail(&slot->node, &dev_list);
slot = NULL;
spin_unlock(&list_lock);
}
static struct tegra_aes_slot *aes_find_key_slot(void)
{
struct tegra_aes_slot *slot = NULL;
struct list_head *new_head;
int empty;
spin_lock(&list_lock);
empty = list_empty(&dev_list);
if (!empty) {
slot = list_entry(&dev_list, struct tegra_aes_slot, node);
new_head = dev_list.next;
list_del(&dev_list);
dev_list.next = new_head->next;
dev_list.prev = NULL;
}
spin_unlock(&list_lock);
return slot;
}
static int aes_set_key(struct tegra_aes_dev *dd)
{
u32 value, cmdq[2];
struct tegra_aes_ctx *ctx = dd->ctx;
int eng_busy, icq_empty, dma_busy;
bool use_ssk = false;
/* use ssk? */
if (!dd->ctx->slot) {
dev_dbg(dd->dev, "using ssk");
dd->ctx->slot = &ssk;
use_ssk = true;
}
/* enable key schedule generation in hardware */
value = aes_readl(dd, TEGRA_AES_SECURE_CONFIG_EXT);
value &= ~TEGRA_AES_SECURE_KEY_SCH_DIS_FIELD;
aes_writel(dd, value, TEGRA_AES_SECURE_CONFIG_EXT);
/* select the key slot */
value = aes_readl(dd, TEGRA_AES_SECURE_CONFIG);
value &= ~TEGRA_AES_SECURE_KEY_INDEX_FIELD;
value |= (ctx->slot->slot_num << TEGRA_AES_SECURE_KEY_INDEX_SHIFT);
aes_writel(dd, value, TEGRA_AES_SECURE_CONFIG);
if (use_ssk)
return 0;
/* copy the key table from sdram to vram */
cmdq[0] = CMD_MEMDMAVD << CMDQ_OPCODE_SHIFT |
MEMDMA_DIR_DTOVRAM << MEMDMA_DIR_SHIFT |
AES_HW_KEY_TABLE_LENGTH_BYTES / sizeof(u32) <<
MEMDMA_NUM_WORDS_SHIFT;
cmdq[1] = (u32)dd->ivkey_phys_base;
aes_writel(dd, cmdq[0], TEGRA_AES_ICMDQUE_WR);
aes_writel(dd, cmdq[1], TEGRA_AES_ICMDQUE_WR);
do {
value = aes_readl(dd, TEGRA_AES_INTR_STATUS);
eng_busy = value & TEGRA_AES_ENGINE_BUSY_FIELD;
icq_empty = value & TEGRA_AES_ICQ_EMPTY_FIELD;
dma_busy = value & TEGRA_AES_DMA_BUSY_FIELD;
} while (eng_busy && !icq_empty && dma_busy);
/* settable command to get key into internal registers */
value = CMD_SETTABLE << CMDQ_OPCODE_SHIFT |
SUBCMD_CRYPTO_TABLE_SEL << CMDQ_TABLESEL_SHIFT |
SUBCMD_VRAM_SEL << CMDQ_VRAMSEL_SHIFT |
(SUBCMD_KEY_TABLE_SEL | ctx->slot->slot_num) <<
CMDQ_KEYTABLEID_SHIFT;
aes_writel(dd, value, TEGRA_AES_ICMDQUE_WR);
do {
value = aes_readl(dd, TEGRA_AES_INTR_STATUS);
eng_busy = value & TEGRA_AES_ENGINE_BUSY_FIELD;
icq_empty = value & TEGRA_AES_ICQ_EMPTY_FIELD;
} while (eng_busy && !icq_empty);
return 0;
}
static int tegra_aes_handle_req(struct tegra_aes_dev *dd)
{
struct crypto_async_request *async_req, *backlog;
struct crypto_ablkcipher *tfm;
struct tegra_aes_ctx *ctx;
struct tegra_aes_reqctx *rctx;
struct ablkcipher_request *req;
unsigned long flags;
int dma_max = AES_HW_DMA_BUFFER_SIZE_BYTES;
int ret = 0, nblocks, total;
int count = 0;
dma_addr_t addr_in, addr_out;
struct scatterlist *in_sg, *out_sg;
if (!dd)
return -EINVAL;
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 -ENODATA;
if (backlog)
backlog->complete(backlog, -EINPROGRESS);
req = ablkcipher_request_cast(async_req);
dev_dbg(dd->dev, "%s: get new req\n", __func__);
if (!req->src || !req->dst)
return -EINVAL;
/* take mutex to access the aes hw */
mutex_lock(&aes_lock);
/* assign new request to device */
dd->req = req;
dd->total = req->nbytes;
dd->in_offset = 0;
dd->in_sg = req->src;
dd->out_offset = 0;
dd->out_sg = req->dst;
in_sg = dd->in_sg;
out_sg = dd->out_sg;
total = dd->total;
tfm = crypto_ablkcipher_reqtfm(req);
rctx = ablkcipher_request_ctx(req);
ctx = crypto_ablkcipher_ctx(tfm);
rctx->mode &= FLAGS_MODE_MASK;
dd->flags = (dd->flags & ~FLAGS_MODE_MASK) | rctx->mode;
dd->iv = (u8 *)req->info;
dd->ivlen = crypto_ablkcipher_ivsize(tfm);
/* assign new context to device */
ctx->dd = dd;
dd->ctx = ctx;
if (ctx->flags & FLAGS_NEW_KEY) {
/* copy the key */
memcpy(dd->ivkey_base, ctx->key, ctx->keylen);
memset(dd->ivkey_base + ctx->keylen, 0, AES_HW_KEY_TABLE_LENGTH_BYTES - ctx->keylen);
aes_set_key(dd);
ctx->flags &= ~FLAGS_NEW_KEY;
}
if (((dd->flags & FLAGS_CBC) || (dd->flags & FLAGS_OFB)) && dd->iv) {
/* set iv to the aes hw slot
* Hw generates updated iv only after iv is set in slot.
* So key and iv is passed asynchronously.
*/
memcpy(dd->buf_in, dd->iv, dd->ivlen);
ret = aes_start_crypt(dd, (u32)dd->dma_buf_in,
dd->dma_buf_out, 1, FLAGS_CBC, false);
if (ret < 0) {
dev_err(dd->dev, "aes_start_crypt fail(%d)\n", ret);
goto out;
}
}
while (total) {
dev_dbg(dd->dev, "remain: %d\n", total);
ret = dma_map_sg(dd->dev, in_sg, 1, DMA_TO_DEVICE);
if (!ret) {
dev_err(dd->dev, "dma_map_sg() error\n");
goto out;
}
ret = dma_map_sg(dd->dev, out_sg, 1, DMA_FROM_DEVICE);
if (!ret) {
dev_err(dd->dev, "dma_map_sg() error\n");
dma_unmap_sg(dd->dev, dd->in_sg,
1, DMA_TO_DEVICE);
goto out;
}
addr_in = sg_dma_address(in_sg);
addr_out = sg_dma_address(out_sg);
dd->flags |= FLAGS_FAST;
count = min_t(int, sg_dma_len(in_sg), dma_max);
WARN_ON(sg_dma_len(in_sg) != sg_dma_len(out_sg));
nblocks = DIV_ROUND_UP(count, AES_BLOCK_SIZE);
ret = aes_start_crypt(dd, addr_in, addr_out, nblocks,
dd->flags, true);
dma_unmap_sg(dd->dev, out_sg, 1, DMA_FROM_DEVICE);
dma_unmap_sg(dd->dev, in_sg, 1, DMA_TO_DEVICE);
if (ret < 0) {
dev_err(dd->dev, "aes_start_crypt fail(%d)\n", ret);
goto out;
}
dd->flags &= ~FLAGS_FAST;
dev_dbg(dd->dev, "out: copied %d\n", count);
total -= count;
in_sg = sg_next(in_sg);
out_sg = sg_next(out_sg);
WARN_ON(((total != 0) && (!in_sg || !out_sg)));
}
out:
mutex_unlock(&aes_lock);
dd->total = total;
if (dd->req->base.complete)
dd->req->base.complete(&dd->req->base, ret);
dev_dbg(dd->dev, "%s: exit\n", __func__);
return ret;
}
static int tegra_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
unsigned int keylen)
{
struct tegra_aes_ctx *ctx = crypto_ablkcipher_ctx(tfm);
struct tegra_aes_dev *dd = aes_dev;
struct tegra_aes_slot *key_slot;
if ((keylen != AES_KEYSIZE_128) && (keylen != AES_KEYSIZE_192) &&
(keylen != AES_KEYSIZE_256)) {
dev_err(dd->dev, "unsupported key size\n");
crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
return -EINVAL;
}
dev_dbg(dd->dev, "keylen: %d\n", keylen);
ctx->dd = dd;
if (key) {
if (!ctx->slot) {
key_slot = aes_find_key_slot();
if (!key_slot) {
dev_err(dd->dev, "no empty slot\n");
return -ENOMEM;
}
ctx->slot = key_slot;
}
memcpy(ctx->key, key, keylen);
ctx->keylen = keylen;
}
ctx->flags |= FLAGS_NEW_KEY;
dev_dbg(dd->dev, "done\n");
return 0;
}
static void aes_workqueue_handler(struct work_struct *work)
{
struct tegra_aes_dev *dd = aes_dev;
int ret;
ret = clk_prepare_enable(dd->aes_clk);
if (ret)
BUG_ON("clock enable failed");
/* empty the crypto queue and then return */
do {
ret = tegra_aes_handle_req(dd);
} while (!ret);
clk_disable_unprepare(dd->aes_clk);
}
static irqreturn_t aes_irq(int irq, void *dev_id)
{
struct tegra_aes_dev *dd = (struct tegra_aes_dev *)dev_id;
u32 value = aes_readl(dd, TEGRA_AES_INTR_STATUS);
int busy = test_bit(FLAGS_BUSY, &dd->flags);
if (!busy) {
dev_dbg(dd->dev, "spurious interrupt\n");
return IRQ_NONE;
}
dev_dbg(dd->dev, "irq_stat: 0x%x\n", value);
if (value & TEGRA_AES_INT_ERROR_MASK)
aes_writel(dd, TEGRA_AES_INT_ERROR_MASK, TEGRA_AES_INTR_STATUS);
if (!(value & TEGRA_AES_ENGINE_BUSY_FIELD))
complete(&dd->op_complete);
else
return IRQ_NONE;
return IRQ_HANDLED;
}
static int tegra_aes_crypt(struct ablkcipher_request *req, unsigned long mode)
{
struct tegra_aes_reqctx *rctx = ablkcipher_request_ctx(req);
struct tegra_aes_dev *dd = aes_dev;
unsigned long flags;
int err = 0;
int busy;
dev_dbg(dd->dev, "nbytes: %d, enc: %d, cbc: %d, ofb: %d\n",
req->nbytes, !!(mode & FLAGS_ENCRYPT),
!!(mode & FLAGS_CBC), !!(mode & FLAGS_OFB));
rctx->mode = mode;
spin_lock_irqsave(&dd->lock, flags);
err = ablkcipher_enqueue_request(&dd->queue, req);
busy = test_and_set_bit(FLAGS_BUSY, &dd->flags);
spin_unlock_irqrestore(&dd->lock, flags);
if (!busy)
queue_work(aes_wq, &aes_work);
return err;
}
static int tegra_aes_ecb_encrypt(struct ablkcipher_request *req)
{
return tegra_aes_crypt(req, FLAGS_ENCRYPT);
}
static int tegra_aes_ecb_decrypt(struct ablkcipher_request *req)
{
return tegra_aes_crypt(req, 0);
}
static int tegra_aes_cbc_encrypt(struct ablkcipher_request *req)
{
return tegra_aes_crypt(req, FLAGS_ENCRYPT | FLAGS_CBC);
}
static int tegra_aes_cbc_decrypt(struct ablkcipher_request *req)
{
return tegra_aes_crypt(req, FLAGS_CBC);
}
static int tegra_aes_ofb_encrypt(struct ablkcipher_request *req)
{
return tegra_aes_crypt(req, FLAGS_ENCRYPT | FLAGS_OFB);
}
static int tegra_aes_ofb_decrypt(struct ablkcipher_request *req)
{
return tegra_aes_crypt(req, FLAGS_OFB);
}
static int tegra_aes_get_random(struct crypto_rng *tfm, u8 *rdata,
unsigned int dlen)
{
struct tegra_aes_dev *dd = aes_dev;
struct tegra_aes_ctx *ctx = &rng_ctx;
int ret, i;
u8 *dest = rdata, *dt = dd->dt;
/* take mutex to access the aes hw */
mutex_lock(&aes_lock);
ret = clk_prepare_enable(dd->aes_clk);
if (ret) {
mutex_unlock(&aes_lock);
return ret;
}
ctx->dd = dd;
dd->ctx = ctx;
dd->flags = FLAGS_ENCRYPT | FLAGS_RNG;
memcpy(dd->buf_in, dt, DEFAULT_RNG_BLK_SZ);
ret = aes_start_crypt(dd, (u32)dd->dma_buf_in,
(u32)dd->dma_buf_out, 1, dd->flags, true);
if (ret < 0) {
dev_err(dd->dev, "aes_start_crypt fail(%d)\n", ret);
dlen = ret;
goto out;
}
memcpy(dest, dd->buf_out, dlen);
/* update the DT */
for (i = DEFAULT_RNG_BLK_SZ - 1; i >= 0; i--) {
dt[i] += 1;
if (dt[i] != 0)
break;
}
out:
clk_disable_unprepare(dd->aes_clk);
mutex_unlock(&aes_lock);
dev_dbg(dd->dev, "%s: done\n", __func__);
return dlen;
}
static int tegra_aes_rng_reset(struct crypto_rng *tfm, u8 *seed,
unsigned int slen)
{
struct tegra_aes_dev *dd = aes_dev;
struct tegra_aes_ctx *ctx = &rng_ctx;
struct tegra_aes_slot *key_slot;
int ret = 0;
u8 tmp[16]; /* 16 bytes = 128 bits of entropy */
u8 *dt;
if (!ctx || !dd) {
dev_err(dd->dev, "ctx=0x%x, dd=0x%x\n",
(unsigned int)ctx, (unsigned int)dd);
return -EINVAL;
}
if (slen < (DEFAULT_RNG_BLK_SZ + AES_KEYSIZE_128)) {
dev_err(dd->dev, "seed size invalid");
return -ENOMEM;
}
/* take mutex to access the aes hw */
mutex_lock(&aes_lock);
if (!ctx->slot) {
key_slot = aes_find_key_slot();
if (!key_slot) {
dev_err(dd->dev, "no empty slot\n");
mutex_unlock(&aes_lock);
return -ENOMEM;
}
ctx->slot = key_slot;
}
ctx->dd = dd;
dd->ctx = ctx;
dd->ctr = 0;
ctx->keylen = AES_KEYSIZE_128;
ctx->flags |= FLAGS_NEW_KEY;
/* copy the key to the key slot */
memcpy(dd->ivkey_base, seed + DEFAULT_RNG_BLK_SZ, AES_KEYSIZE_128);
memset(dd->ivkey_base + AES_KEYSIZE_128, 0, AES_HW_KEY_TABLE_LENGTH_BYTES - AES_KEYSIZE_128);
dd->iv = seed;
dd->ivlen = slen;
dd->flags = FLAGS_ENCRYPT | FLAGS_RNG;
ret = clk_prepare_enable(dd->aes_clk);
if (ret) {
mutex_unlock(&aes_lock);
return ret;
}
aes_set_key(dd);
/* set seed to the aes hw slot */
memcpy(dd->buf_in, dd->iv, DEFAULT_RNG_BLK_SZ);
ret = aes_start_crypt(dd, (u32)dd->dma_buf_in,
dd->dma_buf_out, 1, FLAGS_CBC, false);
if (ret < 0) {
dev_err(dd->dev, "aes_start_crypt fail(%d)\n", ret);
goto out;
}
if (dd->ivlen >= (2 * DEFAULT_RNG_BLK_SZ + AES_KEYSIZE_128)) {
dt = dd->iv + DEFAULT_RNG_BLK_SZ + AES_KEYSIZE_128;
} else {
get_random_bytes(tmp, sizeof(tmp));
dt = tmp;
}
memcpy(dd->dt, dt, DEFAULT_RNG_BLK_SZ);
out:
clk_disable_unprepare(dd->aes_clk);
mutex_unlock(&aes_lock);
dev_dbg(dd->dev, "%s: done\n", __func__);
return ret;
}
static int tegra_aes_cra_init(struct crypto_tfm *tfm)
{
tfm->crt_ablkcipher.reqsize = sizeof(struct tegra_aes_reqctx);
return 0;
}
void tegra_aes_cra_exit(struct crypto_tfm *tfm)
{
struct tegra_aes_ctx *ctx =
crypto_ablkcipher_ctx((struct crypto_ablkcipher *)tfm);
if (ctx && ctx->slot)
aes_release_key_slot(ctx->slot);
}
static struct crypto_alg algs[] = {
{
.cra_name = "ecb(aes)",
.cra_driver_name = "ecb-aes-tegra",
.cra_priority = 300,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_alignmask = 3,
.cra_type = &crypto_ablkcipher_type,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.setkey = tegra_aes_setkey,
.encrypt = tegra_aes_ecb_encrypt,
.decrypt = tegra_aes_ecb_decrypt,
},
}, {
.cra_name = "cbc(aes)",
.cra_driver_name = "cbc-aes-tegra",
.cra_priority = 300,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_alignmask = 3,
.cra_type = &crypto_ablkcipher_type,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_MIN_KEY_SIZE,
.setkey = tegra_aes_setkey,
.encrypt = tegra_aes_cbc_encrypt,
.decrypt = tegra_aes_cbc_decrypt,
}
}, {
.cra_name = "ofb(aes)",
.cra_driver_name = "ofb-aes-tegra",
.cra_priority = 300,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_alignmask = 3,
.cra_type = &crypto_ablkcipher_type,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_MIN_KEY_SIZE,
.setkey = tegra_aes_setkey,
.encrypt = tegra_aes_ofb_encrypt,
.decrypt = tegra_aes_ofb_decrypt,
}
}, {
.cra_name = "ansi_cprng",
.cra_driver_name = "rng-aes-tegra",
.cra_flags = CRYPTO_ALG_TYPE_RNG,
.cra_ctxsize = sizeof(struct tegra_aes_ctx),
.cra_type = &crypto_rng_type,
.cra_u.rng = {
.rng_make_random = tegra_aes_get_random,
.rng_reset = tegra_aes_rng_reset,
.seedsize = AES_KEYSIZE_128 + (2 * DEFAULT_RNG_BLK_SZ),
}
}
};
static int tegra_aes_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct tegra_aes_dev *dd;
struct resource *res;
int err = -ENOMEM, i = 0, j;
dd = devm_kzalloc(dev, sizeof(struct tegra_aes_dev), GFP_KERNEL);
if (dd == NULL) {
dev_err(dev, "unable to alloc data struct.\n");
return err;
}
dd->dev = dev;
platform_set_drvdata(pdev, dd);
dd->slots = devm_kzalloc(dev, sizeof(struct tegra_aes_slot) *
AES_NR_KEYSLOTS, GFP_KERNEL);
if (dd->slots == NULL) {
dev_err(dev, "unable to alloc slot struct.\n");
goto out;
}
spin_lock_init(&dd->lock);
crypto_init_queue(&dd->queue, TEGRA_AES_QUEUE_LENGTH);
/* Get the module base address */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(dev, "invalid resource type: base\n");
err = -ENODEV;
goto out;
}
if (!devm_request_mem_region(&pdev->dev, res->start,
resource_size(res),
dev_name(&pdev->dev))) {
dev_err(&pdev->dev, "Couldn't request MEM resource\n");
return -ENODEV;
}
dd->io_base = devm_ioremap(dev, res->start, resource_size(res));
if (!dd->io_base) {
dev_err(dev, "can't ioremap register space\n");
err = -ENOMEM;
goto out;
}
/* Initialize the vde clock */
dd->aes_clk = clk_get(dev, "vde");
if (IS_ERR(dd->aes_clk)) {
dev_err(dev, "iclock intialization failed.\n");
err = -ENODEV;
goto out;
}
err = clk_set_rate(dd->aes_clk, ULONG_MAX);
if (err) {
dev_err(dd->dev, "iclk set_rate fail(%d)\n", err);
goto out;
}
/*
* the foll contiguous memory is allocated as follows -
* - hardware key table
* - key schedule
*/
dd->ivkey_base = dma_alloc_coherent(dev, AES_HW_KEY_TABLE_LENGTH_BYTES,
&dd->ivkey_phys_base,
GFP_KERNEL);
if (!dd->ivkey_base) {
dev_err(dev, "can not allocate iv/key buffer\n");
err = -ENOMEM;
goto out;
}
dd->buf_in = dma_alloc_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
&dd->dma_buf_in, GFP_KERNEL);
if (!dd->buf_in) {
dev_err(dev, "can not allocate dma-in buffer\n");
err = -ENOMEM;
goto out;
}
dd->buf_out = dma_alloc_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
&dd->dma_buf_out, GFP_KERNEL);
if (!dd->buf_out) {
dev_err(dev, "can not allocate dma-out buffer\n");
err = -ENOMEM;
goto out;
}
init_completion(&dd->op_complete);
aes_wq = alloc_workqueue("tegra_aes_wq", WQ_HIGHPRI | WQ_UNBOUND, 1);
if (!aes_wq) {
dev_err(dev, "alloc_workqueue failed\n");
err = -ENOMEM;
goto out;
}
/* get the irq */
res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!res) {
dev_err(dev, "invalid resource type: base\n");
err = -ENODEV;
goto out;
}
dd->irq = res->start;
err = devm_request_irq(dev, dd->irq, aes_irq, IRQF_TRIGGER_HIGH |
IRQF_SHARED, "tegra-aes", dd);
if (err) {
dev_err(dev, "request_irq failed\n");
goto out;
}
mutex_init(&aes_lock);
INIT_LIST_HEAD(&dev_list);
spin_lock_init(&list_lock);
spin_lock(&list_lock);
for (i = 0; i < AES_NR_KEYSLOTS; i++) {
if (i == SSK_SLOT_NUM)
continue;
dd->slots[i].slot_num = i;
INIT_LIST_HEAD(&dd->slots[i].node);
list_add_tail(&dd->slots[i].node, &dev_list);
}
spin_unlock(&list_lock);
aes_dev = dd;
for (i = 0; i < ARRAY_SIZE(algs); i++) {
algs[i].cra_priority = 300;
algs[i].cra_ctxsize = sizeof(struct tegra_aes_ctx);
algs[i].cra_module = THIS_MODULE;
algs[i].cra_init = tegra_aes_cra_init;
algs[i].cra_exit = tegra_aes_cra_exit;
err = crypto_register_alg(&algs[i]);
if (err)
goto out;
}
dev_info(dev, "registered");
return 0;
out:
for (j = 0; j < i; j++)
crypto_unregister_alg(&algs[j]);
if (dd->ivkey_base)
dma_free_coherent(dev, AES_HW_KEY_TABLE_LENGTH_BYTES,
dd->ivkey_base, dd->ivkey_phys_base);
if (dd->buf_in)
dma_free_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
dd->buf_in, dd->dma_buf_in);
if (dd->buf_out)
dma_free_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
dd->buf_out, dd->dma_buf_out);
if (!IS_ERR(dd->aes_clk))
clk_put(dd->aes_clk);
if (aes_wq)
destroy_workqueue(aes_wq);
spin_lock(&list_lock);
list_del(&dev_list);
spin_unlock(&list_lock);
aes_dev = NULL;
dev_err(dev, "%s: initialization failed.\n", __func__);
return err;
}
static int tegra_aes_remove(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct tegra_aes_dev *dd = platform_get_drvdata(pdev);
int i;
for (i = 0; i < ARRAY_SIZE(algs); i++)
crypto_unregister_alg(&algs[i]);
cancel_work_sync(&aes_work);
destroy_workqueue(aes_wq);
spin_lock(&list_lock);
list_del(&dev_list);
spin_unlock(&list_lock);
dma_free_coherent(dev, AES_HW_KEY_TABLE_LENGTH_BYTES,
dd->ivkey_base, dd->ivkey_phys_base);
dma_free_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
dd->buf_in, dd->dma_buf_in);
dma_free_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
dd->buf_out, dd->dma_buf_out);
clk_put(dd->aes_clk);
aes_dev = NULL;
return 0;
}
static struct of_device_id tegra_aes_of_match[] = {
{ .compatible = "nvidia,tegra20-aes", },
{ .compatible = "nvidia,tegra30-aes", },
{ },
};
static struct platform_driver tegra_aes_driver = {
.probe = tegra_aes_probe,
.remove = tegra_aes_remove,
.driver = {
.name = "tegra-aes",
.owner = THIS_MODULE,
.of_match_table = tegra_aes_of_match,
},
};
module_platform_driver(tegra_aes_driver);
MODULE_DESCRIPTION("Tegra AES/OFB/CPRNG hw acceleration support.");
MODULE_AUTHOR("NVIDIA Corporation");
MODULE_LICENSE("GPL v2");