2013-05-19 20:00:00

by Tobias Rauter

[permalink] [raw]
Subject: [PATCH v2 1/1] crypto: Added support for Freescale's DCP co-processor

This patch enables the DCP crypto functionality on imx28.
Currently, only aes-128-cbc is supported.
Moreover, the dcpboot misc-device, which is used by Freescale's
SDK tools and uses a non-software-readable OTP-key, is added.

Changes of v2:
- ring buffer for hardware-descriptors
- use of ablkcipher walk
- OTP key encryption/decryption via misc-device
(compatible to Freescale-SDK)
- overall cleanup

The DCP is also capable of sha1/sha256 but I won't be able to add
that anytime soon.
Tested with built-in runtime-self-test, tcrypt and openssl via
cryptodev 1.6 on imx28-evk and a custom built imx28-board.


Signed-off-by: Tobias Rauter <[email protected]>
---
arch/arm/boot/dts/imx28.dtsi | 2 +-
drivers/crypto/Kconfig | 10 +
drivers/crypto/Makefile | 1 +
drivers/crypto/dcp.c | 925 +++++++++++++++++++++++++++++++++++++++++++
4 files changed, 937 insertions(+), 1 deletion(-)
create mode 100644 drivers/crypto/dcp.c

diff --git a/arch/arm/boot/dts/imx28.dtsi b/arch/arm/boot/dts/imx28.dtsi
index 600f7cb..077d0eb 100644
--- a/arch/arm/boot/dts/imx28.dtsi
+++ b/arch/arm/boot/dts/imx28.dtsi
@@ -699,7 +699,7 @@
[email protected] {
reg = <0x80028000 0x2000>;
interrupts = <52 53 54>;
- status = "disabled";
+ compatible = "fsl-dcp";
};

[email protected] {
diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index dffb855..3e11215 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -286,6 +286,16 @@ config CRYPTO_DEV_SAHARA
This option enables support for the SAHARA HW crypto accelerator
found in some Freescale i.MX chips.

+config CRYPTO_DEV_DCP
+ tristate "Support for the DCP engine"
+ depends on ARCH_MXS && OF
+ select CRYPTO_BLKCIPHER
+ select CRYPTO_AES
+ select CRYPTO_CBC
+ help
+ This options enables support for the hardware crypto-acceleration
+ capabilities of the DCP co-processor
+
config CRYPTO_DEV_S5P
tristate "Support for Samsung S5PV210 crypto accelerator"
depends on ARCH_S5PV210
diff --git a/drivers/crypto/Makefile b/drivers/crypto/Makefile
index 38ce13d..b4946dd 100644
--- a/drivers/crypto/Makefile
+++ b/drivers/crypto/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_CRYPTO_DEV_OMAP_SHAM) += omap-sham.o
obj-$(CONFIG_CRYPTO_DEV_OMAP_AES) += omap-aes.o
obj-$(CONFIG_CRYPTO_DEV_PICOXCELL) += picoxcell_crypto.o
obj-$(CONFIG_CRYPTO_DEV_SAHARA) += sahara.o
+obj-$(CONFIG_CRYPTO_DEV_DCP) += dcp.o
obj-$(CONFIG_CRYPTO_DEV_S5P) += s5p-sss.o
obj-$(CONFIG_CRYPTO_DEV_TEGRA_AES) += tegra-aes.o
obj-$(CONFIG_CRYPTO_DEV_UX500) += ux500/
diff --git a/drivers/crypto/dcp.c b/drivers/crypto/dcp.c
new file mode 100644
index 0000000..eea194c
--- /dev/null
+++ b/drivers/crypto/dcp.c
@@ -0,0 +1,925 @@
+/*
+ * Cryptographic API.
+ *
+ * Support for DCP cryptographic accelerator.
+ *
+ * Copyright (c) 2013
+ * Author: Tobias Rauter <[email protected]>
+ *
+ * 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.
+ *
+ * Based on tegra-aes.c, dcp.c (from freescale SDK) and sahara.c
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.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 <linux/delay.h>
+#include <linux/crypto.h>
+#include <linux/miscdevice.h>
+
+#include <crypto/scatterwalk.h>
+#include <crypto/aes.h>
+
+
+/* IOCTL for DCP OTP Key AES - taken from Freescale's SDK*/
+#define DBS_IOCTL_BASE 'd'
+#define DBS_ENC _IOW(DBS_IOCTL_BASE, 0x00, uint8_t[16])
+#define DBS_DEC _IOW(DBS_IOCTL_BASE, 0x01, uint8_t[16])
+
+/* DCP channel used for AES */
+#define USED_CHANNEL 1
+/* Ring Buffers' maximum size */
+#define DCP_MAX_PKG 20
+
+/* Control Register */
+#define DCP_REG_CTRL 0x000
+#define DCP_CTRL_SFRST (1<<31)
+#define DCP_CTRL_CLKGATE (1<<30)
+#define DCP_CTRL_CRYPTO_PRESENT (1<<29)
+#define DCP_CTRL_SHA_PRESENT (1<<28)
+#define DCP_CTRL_GATHER_RES_WRITE (1<<23)
+#define DCP_CTRL_ENABLE_CONTEXT_CACHE (1<<22)
+#define DCP_CTRL_ENABLE_CONTEXT_SWITCH (1<<21)
+#define DCP_CTRL_CH_IRQ_E_0 0x01
+#define DCP_CTRL_CH_IRQ_E_1 0x02
+#define DCP_CTRL_CH_IRQ_E_2 0x04
+#define DCP_CTRL_CH_IRQ_E_3 0x08
+
+/* Status register */
+#define DCP_REG_STAT 0x010
+#define DCP_STAT_OTP_KEY_READY (1<<28)
+#define DCP_STAT_CUR_CHANNEL(stat) ((stat>>24)&0x0F)
+#define DCP_STAT_READY_CHANNEL(stat) ((stat>>16)&0x0F)
+#define DCP_STAT_IRQ(stat) (stat&0x0F)
+#define DCP_STAT_CHAN_0 (0x01)
+#define DCP_STAT_CHAN_1 (0x02)
+#define DCP_STAT_CHAN_2 (0x04)
+#define DCP_STAT_CHAN_3 (0x08)
+
+/* Channel Control Register */
+#define DCP_REG_CHAN_CTRL 0x020
+#define DCP_CHAN_CTRL_CH0_IRQ_MERGED (1<<16)
+#define DCP_CHAN_CTRL_HIGH_PRIO_0 (0x0100)
+#define DCP_CHAN_CTRL_HIGH_PRIO_1 (0x0200)
+#define DCP_CHAN_CTRL_HIGH_PRIO_2 (0x0400)
+#define DCP_CHAN_CTRL_HIGH_PRIO_3 (0x0800)
+#define DCP_CHAN_CTRL_ENABLE_0 (0x01)
+#define DCP_CHAN_CTRL_ENABLE_1 (0x02)
+#define DCP_CHAN_CTRL_ENABLE_2 (0x04)
+#define DCP_CHAN_CTRL_ENABLE_3 (0x08)
+
+/*
+ * Channel Registers:
+ * The DCP has 4 channels. Each of this channels
+ * has 4 registers (command pointer, semaphore, status and options).
+ * The address of register REG of channel CHAN is obtained by
+ * dcp_chan_reg(REG, CHAN)
+ */
+#define DCP_REG_CHAN_PTR 0x00000100
+#define DCP_REG_CHAN_SEMA 0x00000110
+#define DCP_REG_CHAN_STAT 0x00000120
+#define DCP_REG_CHAN_OPT 0x00000130
+
+#define DCP_CHAN_STAT_NEXT_CHAIN_IS_0 0x010000
+#define DCP_CHAN_STAT_NO_CHAIN 0x020000
+#define DCP_CHAN_STAT_CONTEXT_ERROR 0x030000
+#define DCP_CHAN_STAT_PAYLOAD_ERROR 0x040000
+#define DCP_CHAN_STAT_INVALID_MODE 0x050000
+#define DCP_CHAN_STAT_PAGEFAULT 0x40
+#define DCP_CHAN_STAT_DST 0x20
+#define DCP_CHAN_STAT_SRC 0x10
+#define DCP_CHAN_STAT_PACKET 0x08
+#define DCP_CHAN_STAT_SETUP 0x04
+#define DCP_CHAN_STAT_MISMATCH 0x02
+
+/* hw packet control*/
+
+#define DCP_PKT_PAYLOAD_KEY (1<<11)
+#define DCP_PKT_OTP_KEY (1<<10)
+#define DCP_PKT_CIPHER_INIT (1<<9)
+#define DCP_PKG_CIPHER_ENCRYPT (1<<8)
+#define DCP_PKT_CIPHER_ENABLE (1<<5)
+#define DCP_PKT_DECR_SEM (1<<1)
+#define DCP_PKT_CHAIN (1<<2)
+#define DCP_PKT_IRQ 1
+
+#define DCP_PKT_MODE_CBC (1<<4)
+#define DCP_PKT_KEYSELECT_OTP (0xFF<<8)
+
+/* cipher flags */
+#define DCP_ENC 0x0001
+#define DCP_DEC 0x0002
+#define DCP_ECB 0x0004
+#define DCP_CBC 0x0008
+#define DCP_CBC_INIT 0x0010
+#define DCP_NEW_KEY 0x0040
+#define DCP_OTP_KEY 0x0080
+#define DCP_AES 0x1000
+
+/* DCP Flags */
+#define DCP_FLAG_BUSY 0x01
+#define DCP_FLAG_PRODUCING 0x02
+
+/* clock defines */
+#define CLOCK_ON 1
+#define CLOCK_OFF 0
+
+struct dcp_dev_req_ctx {
+ int mode;
+};
+
+struct dcp_op {
+ unsigned int flags;
+ u8 key[AES_KEYSIZE_128];
+ int keylen;
+
+ struct ablkcipher_request *req;
+ struct crypto_ablkcipher *fallback;
+
+ uint32_t stat;
+ uint32_t pkt1;
+ uint32_t pkt2;
+ struct ablkcipher_walk walk;
+};
+
+struct dcp_dev {
+ struct device *dev;
+ void __iomem *dcp_regs_base;
+
+ int dcp_vmi_irq;
+ int dcp_irq;
+
+ spinlock_t queue_lock;
+ struct crypto_queue queue;
+
+ uint32_t pkt_produced;
+ uint32_t pkt_consumed;
+
+ struct dcp_hw_packet *hw_pkg[DCP_MAX_PKG];
+ dma_addr_t hw_phys_pkg;
+
+ /* [KEY][IV] Both with 16 Bytes */
+ u8 *payload_base;
+ dma_addr_t payload_base_dma;
+
+
+ struct tasklet_struct done_task;
+ struct tasklet_struct queue_task;
+ struct timer_list watchdog;
+
+ unsigned long flags;
+
+ struct dcp_op *ctx;
+
+ struct miscdevice dcp_bootstream_misc;
+};
+
+struct dcp_hw_packet {
+ uint32_t next;
+ uint32_t pkt1;
+ uint32_t pkt2;
+ uint32_t src;
+ uint32_t dst;
+ uint32_t size;
+ uint32_t payload;
+ uint32_t stat;
+};
+
+struct dcp_dev *global_dev;
+
+static inline u32 dcp_chan_reg(u32 reg, int chan)
+{
+ return reg + (chan) * 0x40;
+}
+
+static inline void dcp_write(struct dcp_dev *dev, u32 data, u32 reg)
+{
+ writel(data, dev->dcp_regs_base + reg);
+}
+
+static inline void dcp_set(struct dcp_dev *dev, u32 data, u32 reg)
+{
+ writel(data, dev->dcp_regs_base + (reg | 0x04));
+}
+
+static inline void dcp_clear(struct dcp_dev *dev, u32 data, u32 reg)
+{
+ writel(data, dev->dcp_regs_base + (reg | 0x08));
+}
+
+static inline void dcp_toggle(struct dcp_dev *dev, u32 data, u32 reg)
+{
+ writel(data, dev->dcp_regs_base + (reg | 0x0C));
+}
+
+static inline unsigned int dcp_read(struct dcp_dev *dev, u32 reg)
+{
+ return readl(dev->dcp_regs_base + reg);
+}
+
+void dcp_dma_unmap(struct dcp_dev *dev, struct dcp_hw_packet *pkt)
+{
+ dma_unmap_page(dev->dev, pkt->src, pkt->size, DMA_TO_DEVICE);
+ dma_unmap_page(dev->dev, pkt->dst, pkt->size, DMA_FROM_DEVICE);
+ dev_dbg(dev->dev, "unmap packet %x", (unsigned int) pkt);
+}
+
+int dcp_dma_map(struct dcp_dev *dev,
+ struct ablkcipher_walk *walk, struct dcp_hw_packet *pkt)
+{
+ dev_dbg(dev->dev, "map packet %x", (unsigned int) pkt);
+ /* align to length = 16 */
+ pkt->size = walk->nbytes - (walk->nbytes % 16);
+
+ pkt->src = dma_map_page(dev->dev, walk->src.page, walk->src.offset,
+ pkt->size, DMA_TO_DEVICE);
+
+ if (pkt->src == 0) {
+ dev_err(dev->dev, "Unable to map src");
+ return -ENOMEM;
+ }
+
+ pkt->dst = dma_map_page(dev->dev, walk->dst.page, walk->dst.offset,
+ pkt->size, DMA_FROM_DEVICE);
+
+ if (pkt->dst == 0) {
+ dev_err(dev->dev, "Unable to map dst");
+ dma_unmap_page(dev->dev, pkt->src, pkt->size, DMA_TO_DEVICE);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void dcp_op_one(struct dcp_dev *dev, struct dcp_hw_packet *pkt,
+ uint8_t last)
+{
+ struct dcp_op *ctx = dev->ctx;
+ pkt->pkt1 = ctx->pkt1;
+ pkt->pkt2 = ctx->pkt2;
+
+ pkt->payload = (u32) dev->payload_base_dma;
+ pkt->stat = 0;
+
+ if (ctx->flags & DCP_CBC_INIT) {
+ pkt->pkt1 |= DCP_PKT_CIPHER_INIT;
+ ctx->flags &= ~DCP_CBC_INIT;
+ }
+
+ mod_timer(&dev->watchdog, jiffies + msecs_to_jiffies(500));
+ pkt->pkt1 |= DCP_PKT_IRQ;
+ if (!last)
+ pkt->pkt1 |= DCP_PKT_CHAIN;
+
+ dev->pkt_produced++;
+
+ dcp_write(dev, 1,
+ dcp_chan_reg(DCP_REG_CHAN_SEMA, USED_CHANNEL));
+}
+
+static void dcp_op_proceed(struct dcp_dev *dev)
+{
+ struct dcp_op *ctx = dev->ctx;
+ struct dcp_hw_packet *pkt;
+
+ while (ctx->walk.nbytes) {
+ int err = 0;
+
+ pkt = dev->hw_pkg[dev->pkt_produced % DCP_MAX_PKG];
+ err = dcp_dma_map(dev, &ctx->walk, pkt);
+ if (err) {
+ dev->ctx->stat |= err;
+ /* start timer to wait for already set up calls */
+ mod_timer(&dev->watchdog,
+ jiffies + msecs_to_jiffies(500));
+ break;
+ }
+
+
+ err = ctx->walk.nbytes - pkt->size;
+ ablkcipher_walk_done(dev->ctx->req, &dev->ctx->walk, err);
+
+ dcp_op_one(dev, pkt, ctx->walk.nbytes == 0);
+ /* we have to wait if no space is left in buffer */
+ if (dev->pkt_produced - dev->pkt_consumed == DCP_MAX_PKG)
+ break;
+ }
+ clear_bit(DCP_FLAG_PRODUCING, &dev->flags);
+}
+
+static void dcp_op_start(struct dcp_dev *dev, uint8_t use_walk)
+{
+ struct dcp_op *ctx = dev->ctx;
+
+ if (ctx->flags & DCP_NEW_KEY) {
+ memcpy(dev->payload_base, ctx->key, ctx->keylen);
+ ctx->flags &= ~DCP_NEW_KEY;
+ }
+
+ ctx->pkt1 = 0;
+ ctx->pkt1 |= DCP_PKT_CIPHER_ENABLE;
+ ctx->pkt1 |= DCP_PKT_DECR_SEM;
+
+ if (ctx->flags & DCP_OTP_KEY)
+ ctx->pkt1 |= DCP_PKT_OTP_KEY;
+ else
+ ctx->pkt1 |= DCP_PKT_PAYLOAD_KEY;
+
+ if (ctx->flags & DCP_ENC)
+ ctx->pkt1 |= DCP_PKG_CIPHER_ENCRYPT;
+
+ ctx->pkt2 = 0;
+ if (ctx->flags & DCP_CBC)
+ ctx->pkt2 |= DCP_PKT_MODE_CBC;
+
+ dev->pkt_produced = 0;
+ dev->pkt_consumed = 0;
+
+ ctx->stat = 0;
+ dcp_clear(dev, -1, dcp_chan_reg(DCP_REG_CHAN_STAT, USED_CHANNEL));
+ dcp_write(dev, (u32) dev->hw_phys_pkg,
+ dcp_chan_reg(DCP_REG_CHAN_PTR, USED_CHANNEL));
+
+ set_bit(DCP_FLAG_PRODUCING, &dev->flags);
+
+ if (use_walk) {
+ ablkcipher_walk_init(&ctx->walk, ctx->req->dst,
+ ctx->req->src, ctx->req->nbytes);
+ ablkcipher_walk_phys(ctx->req, &ctx->walk);
+ dcp_op_proceed(dev);
+ } else {
+ dcp_op_one(dev, dev->hw_pkg[0], 1);
+ clear_bit(DCP_FLAG_PRODUCING, &dev->flags);
+ }
+}
+
+static void dcp_done_task(unsigned long data)
+{
+ struct dcp_dev *dev = (struct dcp_dev *)data;
+ struct dcp_hw_packet *last_packet;
+ int fin;
+ fin = 0;
+
+ for (last_packet = dev->hw_pkg[(dev->pkt_consumed) % DCP_MAX_PKG];
+ last_packet->stat == 1;
+ last_packet =
+ dev->hw_pkg[++(dev->pkt_consumed) % DCP_MAX_PKG]) {
+
+ dcp_dma_unmap(dev, last_packet);
+ last_packet->stat = 0;
+ fin++;
+ }
+ /* the last call of this function already consumed this IRQ's packet */
+ if (fin == 0)
+ return;
+
+ dev_dbg(dev->dev,
+ "Packet(s) done with status %x; finished: %d, produced:%d, complete consumed: %d",
+ dev->ctx->stat, fin, dev->pkt_produced, dev->pkt_consumed);
+
+ last_packet = dev->hw_pkg[(dev->pkt_consumed - 1) % DCP_MAX_PKG];
+ if (!dev->ctx->stat && last_packet->pkt1 & DCP_PKT_CHAIN) {
+ if (!test_and_set_bit(DCP_FLAG_PRODUCING, &dev->flags))
+ dcp_op_proceed(dev);
+ return;
+ }
+
+ while (unlikely(dev->pkt_consumed < dev->pkt_produced)) {
+ dcp_dma_unmap(dev,
+ dev->hw_pkg[dev->pkt_consumed++ % DCP_MAX_PKG]);
+ }
+
+ if (dev->ctx->flags & DCP_OTP_KEY) {
+ /* we used the miscdevice, no walk to finish */
+ clear_bit(DCP_FLAG_BUSY, &dev->flags);
+ return;
+ }
+
+ ablkcipher_walk_complete(&dev->ctx->walk);
+ dev->ctx->req->base.complete(&dev->ctx->req->base,
+ dev->ctx->stat);
+ dev->ctx->req = 0;
+ /* in case there are other requests in the queue */
+ tasklet_schedule(&dev->queue_task);
+}
+
+void dcp_watchdog(unsigned long data)
+{
+ struct dcp_dev *dev = (struct dcp_dev *)data;
+ dev->ctx->stat |= dcp_read(dev,
+ dcp_chan_reg(DCP_REG_CHAN_STAT, USED_CHANNEL));
+
+ dev_err(dev->dev, "Timeout, Channel status: %x", dev->ctx->stat);
+
+ if (!dev->ctx->stat)
+ dev->ctx->stat = -ETIMEDOUT;
+
+ dcp_done_task(data);
+}
+
+
+static irqreturn_t dcp_common_irq(int irq, void *context)
+{
+ u32 msk;
+ struct dcp_dev *dev = (struct dcp_dev *) context;
+
+ del_timer(&dev->watchdog);
+
+ msk = DCP_STAT_IRQ(dcp_read(dev, DCP_REG_STAT));
+ dcp_clear(dev, msk, DCP_REG_STAT);
+ if (msk == 0)
+ return IRQ_NONE;
+
+ dev->ctx->stat |= dcp_read(dev,
+ dcp_chan_reg(DCP_REG_CHAN_STAT, USED_CHANNEL));
+
+ if (msk & DCP_STAT_CHAN_1)
+ tasklet_schedule(&dev->done_task);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t dcp_vmi_irq(int irq, void *context)
+{
+ return dcp_common_irq(irq, context);
+}
+
+static irqreturn_t dcp_irq(int irq, void *context)
+{
+ return dcp_common_irq(irq, context);
+}
+
+static void dcp_crypt(struct dcp_dev *dev, struct dcp_op *ctx)
+{
+ dev->ctx = ctx;
+
+ if ((ctx->flags & DCP_CBC) && ctx->req->info) {
+ ctx->flags |= DCP_CBC_INIT;
+ memcpy(dev->payload_base + AES_KEYSIZE_128,
+ ctx->req->info, AES_KEYSIZE_128);
+ }
+
+ dcp_op_start(dev, 1);
+}
+
+static void dcp_queue_task(unsigned long data)
+{
+ struct dcp_dev *dev = (struct dcp_dev *) data;
+ struct crypto_async_request *async_req, *backlog;
+ struct crypto_ablkcipher *tfm;
+ struct dcp_op *ctx;
+ struct dcp_dev_req_ctx *rctx;
+ struct ablkcipher_request *req;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dev->queue_lock, flags);
+
+ backlog = crypto_get_backlog(&dev->queue);
+ async_req = crypto_dequeue_request(&dev->queue);
+
+ spin_unlock_irqrestore(&dev->queue_lock, flags);
+
+ if (!async_req)
+ goto ret_nothing_done;
+
+ if (backlog)
+ backlog->complete(backlog, -EINPROGRESS);
+
+ req = ablkcipher_request_cast(async_req);
+ tfm = crypto_ablkcipher_reqtfm(req);
+ rctx = ablkcipher_request_ctx(req);
+ ctx = crypto_ablkcipher_ctx(tfm);
+
+ if (!req->src || !req->dst)
+ goto ret_nothing_done;
+
+ ctx->flags |= rctx->mode;
+ ctx->req = req;
+
+ dcp_crypt(dev, ctx);
+
+ return;
+
+ret_nothing_done:
+ clear_bit(DCP_FLAG_BUSY, &dev->flags);
+}
+
+
+static int dcp_cra_init(struct crypto_tfm *tfm)
+{
+ const char *name = tfm->__crt_alg->cra_name;
+ struct dcp_op *ctx = crypto_tfm_ctx(tfm);
+
+ tfm->crt_ablkcipher.reqsize = sizeof(struct dcp_dev_req_ctx);
+
+ ctx->fallback = crypto_alloc_ablkcipher(name, 0,
+ CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK);
+
+ if (IS_ERR(ctx->fallback)) {
+ dev_err(global_dev->dev, "Error allocating fallback algo %s\n",
+ name);
+ return PTR_ERR(ctx->fallback);
+ }
+
+ return 0;
+}
+
+static void dcp_cra_exit(struct crypto_tfm *tfm)
+{
+ struct dcp_op *ctx = crypto_tfm_ctx(tfm);
+
+ if (ctx->fallback)
+ crypto_free_ablkcipher(ctx->fallback);
+
+ ctx->fallback = NULL;
+}
+
+/* async interface */
+static int dcp_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
+ unsigned int len)
+{
+ struct dcp_op *ctx = crypto_ablkcipher_ctx(tfm);
+ unsigned int ret = 0;
+ ctx->keylen = len;
+ ctx->flags = 0;
+ if (len == AES_KEYSIZE_128) {
+ if (memcmp(ctx->key, key, AES_KEYSIZE_128)) {
+ memcpy(ctx->key, key, len);
+ ctx->flags |= DCP_NEW_KEY;
+ }
+ return 0;
+ }
+
+ ctx->fallback->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
+ ctx->fallback->base.crt_flags |=
+ (tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
+
+ ret = crypto_ablkcipher_setkey(ctx->fallback, key, len);
+ if (ret) {
+ struct crypto_tfm *tfm_aux = crypto_ablkcipher_tfm(tfm);
+
+ tfm_aux->crt_flags &= ~CRYPTO_TFM_RES_MASK;
+ tfm_aux->crt_flags |=
+ (ctx->fallback->base.crt_flags & CRYPTO_TFM_RES_MASK);
+ }
+ return ret;
+}
+
+static int dcp_aes_cbc_crypt(struct ablkcipher_request *req, int mode)
+{
+ struct dcp_dev_req_ctx *rctx = ablkcipher_request_ctx(req);
+ struct dcp_dev *dev = global_dev;
+ unsigned long flags;
+ int err = 0;
+
+ if (!IS_ALIGNED(req->nbytes, AES_BLOCK_SIZE))
+ return -EINVAL;
+
+ rctx->mode = mode;
+
+ spin_lock_irqsave(&dev->queue_lock, flags);
+ err = ablkcipher_enqueue_request(&dev->queue, req);
+ spin_unlock_irqrestore(&dev->queue_lock, flags);
+
+ flags = test_and_set_bit(DCP_FLAG_BUSY, &dev->flags);
+
+ if (!(flags & DCP_FLAG_BUSY))
+ tasklet_schedule(&dev->queue_task);
+
+ return err;
+}
+
+static int dcp_aes_cbc_encrypt(struct ablkcipher_request *req)
+{
+ struct crypto_tfm *tfm =
+ crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
+ struct dcp_op *ctx = crypto_ablkcipher_ctx(
+ crypto_ablkcipher_reqtfm(req));
+
+ if (unlikely(ctx->keylen != AES_KEYSIZE_128)) {
+ int err = 0;
+ ablkcipher_request_set_tfm(req, ctx->fallback);
+ err = crypto_ablkcipher_encrypt(req);
+ ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
+ return err;
+ }
+
+ return dcp_aes_cbc_crypt(req, DCP_AES | DCP_ENC | DCP_CBC);
+}
+
+static int dcp_aes_cbc_decrypt(struct ablkcipher_request *req)
+{
+ struct crypto_tfm *tfm =
+ crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
+ struct dcp_op *ctx = crypto_ablkcipher_ctx(
+ crypto_ablkcipher_reqtfm(req));
+
+ if (unlikely(ctx->keylen != AES_KEYSIZE_128)) {
+ int err = 0;
+ ablkcipher_request_set_tfm(req, ctx->fallback);
+ err = crypto_ablkcipher_decrypt(req);
+ ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
+ return err;
+ }
+ return dcp_aes_cbc_crypt(req, DCP_AES | DCP_DEC | DCP_CBC);
+}
+
+static struct crypto_alg algs[] = {
+ {
+ .cra_name = "cbc(aes)",
+ .cra_driver_name = "dcp-cbc-aes",
+ .cra_alignmask = 3,
+ .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC |
+ CRYPTO_ALG_NEED_FALLBACK,
+ .cra_blocksize = AES_KEYSIZE_128,
+ .cra_type = &crypto_ablkcipher_type,
+ .cra_priority = 300,
+ .cra_u.ablkcipher = {
+ .min_keysize = AES_KEYSIZE_128,
+ .max_keysize = AES_KEYSIZE_128,
+ .setkey = dcp_aes_setkey,
+ .encrypt = dcp_aes_cbc_encrypt,
+ .decrypt = dcp_aes_cbc_decrypt,
+ .ivsize = AES_KEYSIZE_128,
+ }
+
+ },
+};
+
+/* DCP bootstream verification interface: uses OTP key for crypto */
+static int dcp_bootstream_open(struct inode *inode, struct file *file)
+{
+ file->private_data = container_of((file->private_data),
+ struct dcp_dev, dcp_bootstream_misc);
+ return 0;
+}
+
+static long dcp_bootstream_ioctl(struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ struct dcp_dev *dev = (struct dcp_dev *) file->private_data;
+ void __user *argp = (void __user *)arg;
+ int ret;
+
+ if (dev == NULL)
+ return -EBADF;
+
+ if (cmd != DBS_ENC && cmd != DBS_DEC)
+ return -EINVAL;
+
+ if (copy_from_user(dev->payload_base, argp, 16))
+ return -EFAULT;
+
+ if (test_and_set_bit(DCP_FLAG_BUSY, &dev->flags))
+ return -EAGAIN;
+
+ dev->ctx = kzalloc(sizeof(struct dcp_op), GFP_KERNEL);
+ if (!dev->ctx) {
+ dev_err(dev->dev,
+ "cannot allocate context for OTP crypto");
+ clear_bit(DCP_FLAG_BUSY, &dev->flags);
+ return -ENOMEM;
+ }
+
+ dev->ctx->flags = DCP_AES | DCP_ECB | DCP_OTP_KEY | DCP_CBC_INIT;
+ dev->ctx->flags |= (cmd == DBS_ENC) ? DCP_ENC : DCP_DEC;
+ dev->hw_pkg[0]->src = dev->payload_base_dma;
+ dev->hw_pkg[0]->dst = dev->payload_base_dma;
+ dev->hw_pkg[0]->size = 16;
+
+ dcp_op_start(dev, 0);
+
+ while (test_bit(DCP_FLAG_BUSY, &dev->flags))
+ cpu_relax();
+
+ ret = dev->ctx->stat;
+ if (!ret && copy_to_user(argp, dev->payload_base, 16))
+ ret = -EFAULT;
+
+ kfree(dev->ctx);
+
+ return ret;
+}
+
+static const struct file_operations dcp_bootstream_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = dcp_bootstream_ioctl,
+ .open = dcp_bootstream_open,
+};
+
+static int dcp_probe(struct platform_device *pdev)
+{
+ struct dcp_dev *dev = NULL;
+ struct resource *r;
+ int i, ret, j;
+
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ if (dev == NULL) {
+ dev_err(&pdev->dev, "Failed to allocate structure\n");
+ ret = -ENOMEM;
+ goto err;
+ }
+ global_dev = dev;
+ dev->dev = &pdev->dev;
+
+ platform_set_drvdata(pdev, dev);
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!r) {
+ dev_err(&pdev->dev, "failed to get IORESOURCE_MEM\n");
+ ret = -ENXIO;
+ goto err_dev;
+ }
+ dev->dcp_regs_base = ioremap(r->start, resource_size(r));
+
+
+ dcp_set(dev, DCP_CTRL_SFRST, DCP_REG_CTRL);
+ udelay(10);
+ dcp_clear(dev, DCP_CTRL_SFRST | DCP_CTRL_CLKGATE, DCP_REG_CTRL);
+
+ dcp_write(dev, DCP_CTRL_GATHER_RES_WRITE |
+ DCP_CTRL_ENABLE_CONTEXT_CACHE | DCP_CTRL_CH_IRQ_E_1,
+ DCP_REG_CTRL);
+
+ dcp_write(dev, DCP_CHAN_CTRL_ENABLE_1, DCP_REG_CHAN_CTRL);
+
+ for (i = 0; i < 4; i++)
+ dcp_clear(dev, -1, dcp_chan_reg(DCP_REG_CHAN_STAT, i));
+
+ dcp_clear(dev, -1, DCP_REG_STAT);
+
+
+ r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (!r) {
+ dev_err(&pdev->dev, "can't get IRQ resource (0)\n");
+ ret = -EIO;
+ goto err_unmap_mem;
+ }
+ dev->dcp_vmi_irq = r->start;
+ ret = request_irq(dev->dcp_vmi_irq, dcp_vmi_irq, 0, "dcp", dev);
+ if (ret != 0) {
+ dev_err(&pdev->dev, "can't request_irq (0)\n");
+ ret = -EIO;
+ goto err_unmap_mem;
+ }
+
+ r = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
+ if (!r) {
+ dev_err(&pdev->dev, "can't get IRQ resource (1)\n");
+ ret = -EIO;
+ goto err_free_irq0;
+ }
+ dev->dcp_irq = r->start;
+ ret = request_irq(dev->dcp_irq, dcp_irq, 0, "dcp", dev);
+ if (ret != 0) {
+ dev_err(&pdev->dev, "can't request_irq (1)\n");
+ ret = -EIO;
+ goto err_free_irq0;
+ }
+
+ dev->hw_pkg[0] = dma_alloc_coherent(&pdev->dev,
+ DCP_MAX_PKG * sizeof(struct dcp_hw_packet),
+ &dev->hw_phys_pkg,
+ GFP_KERNEL);
+ if (!dev->hw_pkg[0]) {
+ dev_err(&pdev->dev, "Could not allocate hw descriptors\n");
+ ret = -ENOMEM;
+ goto err_free_irq1;
+ }
+
+ for (i = 1; i < DCP_MAX_PKG; i++) {
+ dev->hw_pkg[i - 1]->next = dev->hw_phys_pkg
+ + i * sizeof(struct dcp_hw_packet);
+ dev->hw_pkg[i] = dev->hw_pkg[i - 1] + 1;
+ }
+ dev->hw_pkg[i - 1]->next = dev->hw_phys_pkg;
+
+
+ dev->payload_base = dma_alloc_coherent(&pdev->dev, 2 * AES_KEYSIZE_128,
+ &dev->payload_base_dma, GFP_KERNEL);
+ if (!dev->payload_base) {
+ dev_err(&pdev->dev, "Could not allocate memory for key\n");
+ ret = -ENOMEM;
+ goto err_free_hw_packet;
+ }
+ tasklet_init(&dev->queue_task, dcp_queue_task,
+ (unsigned long) dev);
+ tasklet_init(&dev->done_task, dcp_done_task,
+ (unsigned long) dev);
+ spin_lock_init(&dev->queue_lock);
+
+ crypto_init_queue(&dev->queue, 10);
+
+ init_timer(&dev->watchdog);
+ dev->watchdog.function = &dcp_watchdog;
+ dev->watchdog.data = (unsigned long)dev;
+
+ dev->dcp_bootstream_misc.minor = MISC_DYNAMIC_MINOR,
+ dev->dcp_bootstream_misc.name = "dcpboot",
+ dev->dcp_bootstream_misc.fops = &dcp_bootstream_fops,
+ ret = misc_register(&dev->dcp_bootstream_misc);
+ if (ret != 0) {
+ dev_err(dev->dev, "Unable to register misc device\n");
+ goto err_free_key_iv;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(algs); i++) {
+ algs[i].cra_priority = 300;
+ algs[i].cra_ctxsize = sizeof(struct dcp_op);
+ algs[i].cra_module = THIS_MODULE;
+ algs[i].cra_init = dcp_cra_init;
+ algs[i].cra_exit = dcp_cra_exit;
+ if (crypto_register_alg(&algs[i])) {
+ dev_err(&pdev->dev, "register algorithm failed\n");
+ ret = -ENOMEM;
+ goto err_unregister;
+ }
+ }
+ dev_notice(&pdev->dev, "DCP crypto enabled.!\n");
+
+ return 0;
+
+err_unregister:
+ for (j = 0; j < i; j++)
+ crypto_unregister_alg(&algs[j]);
+err_free_key_iv:
+ dma_free_coherent(&pdev->dev, 2 * AES_KEYSIZE_128, dev->payload_base,
+ dev->payload_base_dma);
+err_free_hw_packet:
+ dma_free_coherent(&pdev->dev, DCP_MAX_PKG *
+ sizeof(struct dcp_hw_packet), dev->hw_pkg[0],
+ dev->hw_phys_pkg);
+err_free_irq1:
+ free_irq(dev->dcp_irq, dev);
+err_free_irq0:
+ free_irq(dev->dcp_vmi_irq, dev);
+err_unmap_mem:
+ iounmap((void *) dev->dcp_regs_base);
+err_dev:
+ kfree(dev);
+err:
+ return ret;
+}
+
+static int dcp_remove(struct platform_device *pdev)
+{
+ struct dcp_dev *dev;
+ int j;
+ dev = platform_get_drvdata(pdev);
+ platform_set_drvdata(pdev, NULL);
+
+ dma_free_coherent(&pdev->dev,
+ DCP_MAX_PKG * sizeof(struct dcp_hw_packet),
+ dev->hw_pkg[0], dev->hw_phys_pkg);
+
+ dma_free_coherent(&pdev->dev, 2 * AES_KEYSIZE_128, dev->payload_base,
+ dev->payload_base_dma);
+
+ free_irq(dev->dcp_irq, dev);
+ free_irq(dev->dcp_vmi_irq, dev);
+
+ tasklet_kill(&dev->done_task);
+ tasklet_kill(&dev->queue_task);
+
+ iounmap((void *) dev->dcp_regs_base);
+
+ for (j = 0; j < ARRAY_SIZE(algs); j++)
+ crypto_unregister_alg(&algs[j]);
+
+ misc_deregister(&dev->dcp_bootstream_misc);
+
+ kfree(dev);
+ return 0;
+}
+
+static struct of_device_id fs_dcp_of_match[] = {
+ { .compatible = "fsl-dcp"},
+ {},
+};
+
+static struct platform_driver fs_dcp_driver = {
+ .probe = dcp_probe,
+ .remove = dcp_remove,
+ .driver = {
+ .name = "fsl-dcp",
+ .owner = THIS_MODULE,
+ .of_match_table = fs_dcp_of_match
+ }
+};
+
+module_platform_driver(fs_dcp_driver);
+
+
+MODULE_AUTHOR("Tobias Rauter <[email protected]>");
+MODULE_DESCRIPTION("Freescale DCP Crypto Driver");
+MODULE_LICENSE("GPL");
--
1.8.1.2


2013-05-28 09:51:27

by Herbert Xu

[permalink] [raw]
Subject: Re: [PATCH v2 1/1] crypto: Added support for Freescale's DCP co-processor

On Sun, May 19, 2013 at 09:59:38PM +0200, Tobias Rauter wrote:
> This patch enables the DCP crypto functionality on imx28.
> Currently, only aes-128-cbc is supported.
> Moreover, the dcpboot misc-device, which is used by Freescale's
> SDK tools and uses a non-software-readable OTP-key, is added.
>
> Changes of v2:
> - ring buffer for hardware-descriptors
> - use of ablkcipher walk
> - OTP key encryption/decryption via misc-device
> (compatible to Freescale-SDK)
> - overall cleanup
>
> The DCP is also capable of sha1/sha256 but I won't be able to add
> that anytime soon.
> Tested with built-in runtime-self-test, tcrypt and openssl via
> cryptodev 1.6 on imx28-evk and a custom built imx28-board.
>
>
> Signed-off-by: Tobias Rauter <[email protected]>

Patch applied. Thanks!
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt