[PATCH V2 3/5] ARM: mxs: crypto: Add Freescale MXS DCP driver
Shawn Guo
shawn.guo at linaro.org
Tue Dec 3 06:10:02 EST 2013
On Sun, Dec 01, 2013 at 10:20:21PM +0100, Marek Vasut wrote:
> Add support for the MXS DCP block. The driver currently supports
> SHA-1/SHA-256 hashing and AES-128 CBC/ECB modes. The non-standard
> CRC32 is not yet supported.
>
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Herbert Xu <herbert at gondor.apana.org.au>
> Cc: David S. Miller <davem at davemloft.net>
> Cc: Fabio Estevam <fabio.estevam at freescale.com>
> Cc: Shawn Guo <shawn.guo at linaro.org>
> Cc: linux-crypto at vger.kernel.org
> ---
> .../devicetree/bindings/crypto/fsl-dcp.txt | 18 +
> drivers/crypto/Kconfig | 17 +
> drivers/crypto/Makefile | 1 +
> drivers/crypto/mxs-dcp.c | 1100 ++++++++++++++++++++
> 4 files changed, 1136 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/crypto/fsl-dcp.txt
Since it creates new device tree bindings, please copy
devicetree at vger.kernel.org, so that DT experts can have a chance to
review the bindings.
Shawn
> create mode 100644 drivers/crypto/mxs-dcp.c
>
> V2: Use dma_{un,}map_single instead of large coherent chunk
> Use the DMA mapping function on DCP buffers instead of the large
> coherent chunk. This reduces the amount of cache flushes/invalidations
> and write buffer drains as we do not need to do this every time we
> operate with the coherent memory chunk, but only when really needed.
> Make sure rctx is always inited
> The crypto request context is not zeroed out by the crypto API. While
> this is not documented anywhere, it will produce arcane and hard to
> debug problems. Fix the DCP code so that the request context is always
> properly initialized.
> Minor code and coding-style fixes.
>
> diff --git a/Documentation/devicetree/bindings/crypto/fsl-dcp.txt b/Documentation/devicetree/bindings/crypto/fsl-dcp.txt
> new file mode 100644
> index 0000000..ee8fbf9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/crypto/fsl-dcp.txt
> @@ -0,0 +1,18 @@
> +Freescale DCP (Data Co-Processor) found on i.MX23/i.MX28 .
> +
> +Required properties:
> +- compatible : Should be "fsl,<soc>-dcp"
> +- reg : Should contain MXS DCP registers location and length
> +- interrupts : Should contain MXS DCP interrupt numbers, VMI IRQ and DCP IRQ
> + must be supplied, optionally Secure IRQ can be present, but
> + is currently not implemented and not used.
> +
> +Example:
> +
> +dcp at 80028000 {
> + compatible = "fsl,imx28-dcp", "fsl,imx23-dcp";
> + reg = <0x80028000 0x2000>;
> + interrupts = <52 53>;
> + status = "okay";
> +};
> +
> diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
> index 776d308..a7c2e17 100644
> --- a/drivers/crypto/Kconfig
> +++ b/drivers/crypto/Kconfig
> @@ -389,4 +389,21 @@ config CRYPTO_DEV_ATMEL_SHA
> To compile this driver as a module, choose M here: the module
> will be called atmel-sha.
>
> +config CRYPTO_DEV_MXS_DCP
> + tristate "Support for Freescale MXS DCP"
> + depends on ARCH_MXS
> + select CRYPTO_SHA1
> + select CRYPTO_SHA256
> + select CRYPTO_CBC
> + select CRYPTO_ECB
> + select CRYPTO_AES
> + select CRYPTO_BLKCIPHER
> + select CRYPTO_ALGAPI
> + help
> + The Freescale i.MX23/i.MX28 has SHA1/SHA256 and AES128 CBC/ECB
> + co-processor on the die.
> +
> + To compile this driver as a module, choose M here: the module
> + will be called mxs-dcp.
> +
> endif # CRYPTO_HW
> diff --git a/drivers/crypto/Makefile b/drivers/crypto/Makefile
> index 38ce13d..c7be214 100644
> --- a/drivers/crypto/Makefile
> +++ b/drivers/crypto/Makefile
> @@ -21,3 +21,4 @@ obj-$(CONFIG_CRYPTO_DEV_NX) += nx/
> obj-$(CONFIG_CRYPTO_DEV_ATMEL_AES) += atmel-aes.o
> obj-$(CONFIG_CRYPTO_DEV_ATMEL_TDES) += atmel-tdes.o
> obj-$(CONFIG_CRYPTO_DEV_ATMEL_SHA) += atmel-sha.o
> +obj-$(CONFIG_CRYPTO_DEV_MXS_DCP) += mxs-dcp.o
> diff --git a/drivers/crypto/mxs-dcp.c b/drivers/crypto/mxs-dcp.c
> new file mode 100644
> index 0000000..d41917c
> --- /dev/null
> +++ b/drivers/crypto/mxs-dcp.c
> @@ -0,0 +1,1100 @@
> +/*
> + * Freescale i.MX23/i.MX28 Data Co-Processor driver
> + *
> + * Copyright (C) 2013 Marek Vasut <marex at denx.de>
> + *
> + * The code contained herein is licensed under the GNU General Public
> + * License. You may obtain a copy of the GNU General Public License
> + * Version 2 or later at the following locations:
> + *
> + * http://www.opensource.org/licenses/gpl-license.html
> + * http://www.gnu.org/copyleft/gpl.html
> + */
> +
> +#include <linux/crypto.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/kthread.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/stmp_device.h>
> +
> +#include <crypto/aes.h>
> +#include <crypto/sha.h>
> +#include <crypto/internal/hash.h>
> +
> +#define DCP_MAX_CHANS 4
> +#define DCP_BUF_SZ PAGE_SIZE
> +
> +/* DCP DMA descriptor. */
> +struct dcp_dma_desc {
> + uint32_t next_cmd_addr;
> + uint32_t control0;
> + uint32_t control1;
> + uint32_t source;
> + uint32_t destination;
> + uint32_t size;
> + uint32_t payload;
> + uint32_t status;
> +};
> +
> +/* Coherent aligned block for bounce buffering. */
> +struct dcp_coherent_block {
> + uint8_t aes_in_buf[DCP_BUF_SZ];
> + uint8_t aes_out_buf[DCP_BUF_SZ];
> + uint8_t sha_in_buf[DCP_BUF_SZ];
> +
> + uint8_t aes_key[2 * AES_KEYSIZE_128];
> + uint8_t sha_digest[SHA256_DIGEST_SIZE];
> +
> + struct dcp_dma_desc desc[DCP_MAX_CHANS];
> +};
> +
> +struct dcp {
> + struct device *dev;
> + void __iomem *base;
> +
> + uint32_t caps;
> +
> + struct dcp_coherent_block *coh;
> +
> + struct completion completion[DCP_MAX_CHANS];
> + struct mutex mutex[DCP_MAX_CHANS];
> + struct task_struct *thread[DCP_MAX_CHANS];
> + struct crypto_queue queue[DCP_MAX_CHANS];
> +};
> +
> +enum dcp_chan {
> + DCP_CHAN_HASH_SHA = 0,
> + DCP_CHAN_CRYPTO = 2,
> +};
> +
> +struct dcp_async_ctx {
> + /* Common context */
> + enum dcp_chan chan;
> + uint32_t fill;
> +
> + /* SHA Hash-specific context */
> + struct mutex mutex;
> + uint32_t alg;
> + unsigned int hot:1;
> +
> + /* Crypto-specific context */
> + unsigned int enc:1;
> + unsigned int ecb:1;
> + struct crypto_ablkcipher *fallback;
> + unsigned int key_len;
> + uint8_t key[AES_KEYSIZE_128];
> +};
> +
> +struct dcp_sha_req_ctx {
> + unsigned int init:1;
> + unsigned int fini:1;
> +};
> +
> +/*
> + * There can even be only one instance of the MXS DCP due to the
> + * design of Linux Crypto API.
> + */
> +static struct dcp *global_sdcp;
> +DEFINE_MUTEX(global_mutex);
> +
> +/* DCP register layout. */
> +#define MXS_DCP_CTRL 0x00
> +#define MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES (1 << 23)
> +#define MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING (1 << 22)
> +
> +#define MXS_DCP_STAT 0x10
> +#define MXS_DCP_STAT_CLR 0x18
> +#define MXS_DCP_STAT_IRQ_MASK 0xf
> +
> +#define MXS_DCP_CHANNELCTRL 0x20
> +#define MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK 0xff
> +
> +#define MXS_DCP_CAPABILITY1 0x40
> +#define MXS_DCP_CAPABILITY1_SHA256 (4 << 16)
> +#define MXS_DCP_CAPABILITY1_SHA1 (1 << 16)
> +#define MXS_DCP_CAPABILITY1_AES128 (1 << 0)
> +
> +#define MXS_DCP_CONTEXT 0x50
> +
> +#define MXS_DCP_CH_N_CMDPTR(n) (0x100 + ((n) * 0x40))
> +
> +#define MXS_DCP_CH_N_SEMA(n) (0x110 + ((n) * 0x40))
> +
> +#define MXS_DCP_CH_N_STAT(n) (0x120 + ((n) * 0x40))
> +#define MXS_DCP_CH_N_STAT_CLR(n) (0x128 + ((n) * 0x40))
> +
> +/* DMA descriptor bits. */
> +#define MXS_DCP_CONTROL0_HASH_TERM (1 << 13)
> +#define MXS_DCP_CONTROL0_HASH_INIT (1 << 12)
> +#define MXS_DCP_CONTROL0_PAYLOAD_KEY (1 << 11)
> +#define MXS_DCP_CONTROL0_CIPHER_ENCRYPT (1 << 8)
> +#define MXS_DCP_CONTROL0_CIPHER_INIT (1 << 9)
> +#define MXS_DCP_CONTROL0_ENABLE_HASH (1 << 6)
> +#define MXS_DCP_CONTROL0_ENABLE_CIPHER (1 << 5)
> +#define MXS_DCP_CONTROL0_DECR_SEMAPHORE (1 << 1)
> +#define MXS_DCP_CONTROL0_INTERRUPT (1 << 0)
> +
> +#define MXS_DCP_CONTROL1_HASH_SELECT_SHA256 (2 << 16)
> +#define MXS_DCP_CONTROL1_HASH_SELECT_SHA1 (0 << 16)
> +#define MXS_DCP_CONTROL1_CIPHER_MODE_CBC (1 << 4)
> +#define MXS_DCP_CONTROL1_CIPHER_MODE_ECB (0 << 4)
> +#define MXS_DCP_CONTROL1_CIPHER_SELECT_AES128 (0 << 0)
> +
> +static int mxs_dcp_start_dma(struct dcp_async_ctx *actx)
> +{
> + struct dcp *sdcp = global_sdcp;
> + const int chan = actx->chan;
> + uint32_t stat;
> + int ret;
> + struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
> +
> + dma_addr_t desc_phys = dma_map_single(sdcp->dev, desc, sizeof(*desc),
> + DMA_TO_DEVICE);
> +
> + reinit_completion(&sdcp->completion[chan]);
> +
> + /* Clear status register. */
> + writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(chan));
> +
> + /* Load the DMA descriptor. */
> + writel(desc_phys, sdcp->base + MXS_DCP_CH_N_CMDPTR(chan));
> +
> + /* Increment the semaphore to start the DMA transfer. */
> + writel(1, sdcp->base + MXS_DCP_CH_N_SEMA(chan));
> +
> + ret = wait_for_completion_timeout(&sdcp->completion[chan],
> + msecs_to_jiffies(1000));
> + if (!ret) {
> + dev_err(sdcp->dev, "Channel %i timeout (DCP_STAT=0x%08x)\n",
> + chan, readl(sdcp->base + MXS_DCP_STAT));
> + return -ETIMEDOUT;
> + }
> +
> + stat = readl(sdcp->base + MXS_DCP_CH_N_STAT(chan));
> + if (stat & 0xff) {
> + dev_err(sdcp->dev, "Channel %i error (CH_STAT=0x%08x)\n",
> + chan, stat);
> + return -EINVAL;
> + }
> +
> + dma_unmap_single(sdcp->dev, desc_phys, sizeof(*desc), DMA_TO_DEVICE);
> +
> + return 0;
> +}
> +
> +/*
> + * Encryption (AES128)
> + */
> +static int mxs_dcp_run_aes(struct dcp_async_ctx *actx, int init)
> +{
> + struct dcp *sdcp = global_sdcp;
> + struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
> + int ret;
> +
> + dma_addr_t key_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_key,
> + 2 * AES_KEYSIZE_128,
> + DMA_TO_DEVICE);
> + dma_addr_t src_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_in_buf,
> + DCP_BUF_SZ, DMA_TO_DEVICE);
> + dma_addr_t dst_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_out_buf,
> + DCP_BUF_SZ, DMA_FROM_DEVICE);
> +
> + /* Fill in the DMA descriptor. */
> + desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
> + MXS_DCP_CONTROL0_INTERRUPT |
> + MXS_DCP_CONTROL0_ENABLE_CIPHER;
> +
> + /* Payload contains the key. */
> + desc->control0 |= MXS_DCP_CONTROL0_PAYLOAD_KEY;
> +
> + if (actx->enc)
> + desc->control0 |= MXS_DCP_CONTROL0_CIPHER_ENCRYPT;
> + if (init)
> + desc->control0 |= MXS_DCP_CONTROL0_CIPHER_INIT;
> +
> + desc->control1 = MXS_DCP_CONTROL1_CIPHER_SELECT_AES128;
> +
> + if (actx->ecb)
> + desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_ECB;
> + else
> + desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_CBC;
> +
> + desc->next_cmd_addr = 0;
> + desc->source = src_phys;
> + desc->destination = dst_phys;
> + desc->size = actx->fill;
> + desc->payload = key_phys;
> + desc->status = 0;
> +
> + ret = mxs_dcp_start_dma(actx);
> +
> + dma_unmap_single(sdcp->dev, key_phys, 2 * AES_KEYSIZE_128,
> + DMA_TO_DEVICE);
> + dma_unmap_single(sdcp->dev, src_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
> + dma_unmap_single(sdcp->dev, dst_phys, DCP_BUF_SZ, DMA_FROM_DEVICE);
> +
> + return ret;
> +}
> +
> +static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
> +{
> + struct dcp *sdcp = global_sdcp;
> +
> + struct ablkcipher_request *req = ablkcipher_request_cast(arq);
> + struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
> +
> + struct scatterlist *dst = req->dst;
> + struct scatterlist *src = req->src;
> + const int nents = sg_nents(req->src);
> +
> + const int out_off = DCP_BUF_SZ;
> + uint8_t *in_buf = sdcp->coh->aes_in_buf;
> + uint8_t *out_buf = sdcp->coh->aes_out_buf;
> +
> + uint8_t *out_tmp, *src_buf, *dst_buf = NULL;
> + uint32_t dst_off = 0;
> +
> + uint8_t *key = sdcp->coh->aes_key;
> +
> + int ret = 0;
> + int split = 0;
> + unsigned int i, len, clen, rem = 0;
> + int init = 0;
> +
> + actx->fill = 0;
> +
> + /* Copy the key from the temporary location. */
> + memcpy(key, actx->key, actx->key_len);
> +
> + if (!actx->ecb) {
> + /* Copy the CBC IV just past the key. */
> + memcpy(key + AES_KEYSIZE_128, req->info, AES_KEYSIZE_128);
> + /* CBC needs the INIT set. */
> + init = 1;
> + } else {
> + memset(key + AES_KEYSIZE_128, 0, AES_KEYSIZE_128);
> + }
> +
> + for_each_sg(req->src, src, nents, i) {
> + src_buf = sg_virt(src);
> + len = sg_dma_len(src);
> +
> + do {
> + if (actx->fill + len > out_off)
> + clen = out_off - actx->fill;
> + else
> + clen = len;
> +
> + memcpy(in_buf + actx->fill, src_buf, clen);
> + len -= clen;
> + src_buf += clen;
> + actx->fill += clen;
> +
> + /*
> + * If we filled the buffer or this is the last SG,
> + * submit the buffer.
> + */
> + if (actx->fill == out_off || sg_is_last(src)) {
> + ret = mxs_dcp_run_aes(actx, init);
> + if (ret)
> + return ret;
> + init = 0;
> +
> + out_tmp = out_buf;
> + while (dst && actx->fill) {
> + if (!split) {
> + dst_buf = sg_virt(dst);
> + dst_off = 0;
> + }
> + rem = min(sg_dma_len(dst) - dst_off,
> + actx->fill);
> +
> + memcpy(dst_buf + dst_off, out_tmp, rem);
> + out_tmp += rem;
> + dst_off += rem;
> + actx->fill -= rem;
> +
> + if (dst_off == sg_dma_len(dst)) {
> + dst = sg_next(dst);
> + split = 0;
> + } else {
> + split = 1;
> + }
> + }
> + }
> + } while (len);
> + }
> +
> + return ret;
> +}
> +
> +static int dcp_chan_thread_aes(void *data)
> +{
> + struct dcp *sdcp = global_sdcp;
> + const int chan = DCP_CHAN_CRYPTO;
> +
> + struct crypto_async_request *backlog;
> + struct crypto_async_request *arq;
> +
> + int ret;
> +
> + do {
> + __set_current_state(TASK_INTERRUPTIBLE);
> +
> + mutex_lock(&sdcp->mutex[chan]);
> + backlog = crypto_get_backlog(&sdcp->queue[chan]);
> + arq = crypto_dequeue_request(&sdcp->queue[chan]);
> + mutex_unlock(&sdcp->mutex[chan]);
> +
> + if (backlog)
> + backlog->complete(backlog, -EINPROGRESS);
> +
> + if (arq) {
> + ret = mxs_dcp_aes_block_crypt(arq);
> + arq->complete(arq, ret);
> + continue;
> + }
> +
> + schedule();
> + } while (!kthread_should_stop());
> +
> + return 0;
> +}
> +
> +static int mxs_dcp_block_fallback(struct ablkcipher_request *req, int enc)
> +{
> + struct crypto_tfm *tfm =
> + crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
> + struct dcp_async_ctx *ctx = crypto_ablkcipher_ctx(
> + crypto_ablkcipher_reqtfm(req));
> + int ret;
> +
> + ablkcipher_request_set_tfm(req, ctx->fallback);
> +
> + if (enc)
> + ret = crypto_ablkcipher_encrypt(req);
> + else
> + ret = crypto_ablkcipher_decrypt(req);
> +
> + ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
> +
> + return ret;
> +}
> +
> +static int mxs_dcp_aes_enqueue(struct ablkcipher_request *req, int enc, int ecb)
> +{
> + struct dcp *sdcp = global_sdcp;
> + struct crypto_async_request *arq = &req->base;
> + struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
> + int ret;
> +
> + if (unlikely(actx->key_len != AES_KEYSIZE_128))
> + return mxs_dcp_block_fallback(req, enc);
> +
> + actx->enc = enc;
> + actx->ecb = ecb;
> + actx->chan = DCP_CHAN_CRYPTO;
> +
> + mutex_lock(&sdcp->mutex[actx->chan]);
> + ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
> + mutex_unlock(&sdcp->mutex[actx->chan]);
> +
> + wake_up_process(sdcp->thread[actx->chan]);
> +
> + return -EINPROGRESS;
> +}
> +
> +static int mxs_dcp_aes_ecb_decrypt(struct ablkcipher_request *req)
> +{
> + return mxs_dcp_aes_enqueue(req, 0, 1);
> +}
> +
> +static int mxs_dcp_aes_ecb_encrypt(struct ablkcipher_request *req)
> +{
> + return mxs_dcp_aes_enqueue(req, 1, 1);
> +}
> +
> +static int mxs_dcp_aes_cbc_decrypt(struct ablkcipher_request *req)
> +{
> + return mxs_dcp_aes_enqueue(req, 0, 0);
> +}
> +
> +static int mxs_dcp_aes_cbc_encrypt(struct ablkcipher_request *req)
> +{
> + return mxs_dcp_aes_enqueue(req, 1, 0);
> +}
> +
> +static int mxs_dcp_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
> + unsigned int len)
> +{
> + struct dcp_async_ctx *actx = crypto_ablkcipher_ctx(tfm);
> + unsigned int ret;
> +
> + /*
> + * AES 128 is supposed by the hardware, store key into temporary
> + * buffer and exit. We must use the temporary buffer here, since
> + * there can still be an operation in progress.
> + */
> + actx->key_len = len;
> + if (len == AES_KEYSIZE_128) {
> + memcpy(actx->key, key, len);
> + return 0;
> + }
> +
> + /* Check if the key size is supported by kernel at all. */
> + if (len != AES_KEYSIZE_192 && len != AES_KEYSIZE_256) {
> + tfm->base.crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
> + return -EINVAL;
> + }
> +
> + /*
> + * If the requested AES key size is not supported by the hardware,
> + * but is supported by in-kernel software implementation, we use
> + * software fallback.
> + */
> + actx->fallback->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
> + actx->fallback->base.crt_flags |=
> + tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK;
> +
> + ret = crypto_ablkcipher_setkey(actx->fallback, key, len);
> + if (!ret)
> + return 0;
> +
> + tfm->base.crt_flags &= ~CRYPTO_TFM_RES_MASK;
> + tfm->base.crt_flags |=
> + actx->fallback->base.crt_flags & CRYPTO_TFM_RES_MASK;
> +
> + return ret;
> +}
> +
> +static int mxs_dcp_aes_fallback_init(struct crypto_tfm *tfm)
> +{
> + const char *name = tfm->__crt_alg->cra_name;
> + const uint32_t flags = CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK;
> + struct dcp_async_ctx *actx = crypto_tfm_ctx(tfm);
> + struct crypto_ablkcipher *blk;
> +
> + blk = crypto_alloc_ablkcipher(name, 0, flags);
> + if (IS_ERR(blk))
> + return PTR_ERR(blk);
> +
> + actx->fallback = blk;
> + tfm->crt_ablkcipher.reqsize = sizeof(struct dcp_async_ctx);
> + return 0;
> +}
> +
> +static void mxs_dcp_aes_fallback_exit(struct crypto_tfm *tfm)
> +{
> + struct dcp_async_ctx *actx = crypto_tfm_ctx(tfm);
> +
> + crypto_free_ablkcipher(actx->fallback);
> + actx->fallback = NULL;
> +}
> +
> +/*
> + * Hashing (SHA1/SHA256)
> + */
> +static int mxs_dcp_run_sha(struct ahash_request *req)
> +{
> + struct dcp *sdcp = global_sdcp;
> + int ret;
> +
> + struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
> + struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
> + struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
> +
> + struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
> + dma_addr_t digest_phys = dma_map_single(sdcp->dev,
> + sdcp->coh->sha_digest,
> + SHA256_DIGEST_SIZE,
> + DMA_FROM_DEVICE);
> +
> + dma_addr_t buf_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_in_buf,
> + DCP_BUF_SZ, DMA_TO_DEVICE);
> +
> + /* Fill in the DMA descriptor. */
> + desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
> + MXS_DCP_CONTROL0_INTERRUPT |
> + MXS_DCP_CONTROL0_ENABLE_HASH;
> + if (rctx->init)
> + desc->control0 |= MXS_DCP_CONTROL0_HASH_INIT;
> +
> + desc->control1 = actx->alg;
> + desc->next_cmd_addr = 0;
> + desc->source = buf_phys;
> + desc->destination = 0;
> + desc->size = actx->fill;
> + desc->payload = 0;
> + desc->status = 0;
> +
> + /* Set HASH_TERM bit for last transfer block. */
> + if (rctx->fini) {
> + desc->control0 |= MXS_DCP_CONTROL0_HASH_TERM;
> + desc->payload = digest_phys;
> + }
> +
> + ret = mxs_dcp_start_dma(actx);
> +
> + dma_unmap_single(sdcp->dev, digest_phys, SHA256_DIGEST_SIZE,
> + DMA_FROM_DEVICE);
> + dma_unmap_single(sdcp->dev, buf_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
> +
> + return ret;
> +}
> +
> +static int dcp_sha_req_to_buf(struct crypto_async_request *arq)
> +{
> + struct dcp *sdcp = global_sdcp;
> +
> + struct ahash_request *req = ahash_request_cast(arq);
> + struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
> + struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
> + struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
> + struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
> + const int nents = sg_nents(req->src);
> +
> + uint8_t *digest = sdcp->coh->sha_digest;
> + uint8_t *in_buf = sdcp->coh->sha_in_buf;
> +
> + uint8_t *src_buf;
> +
> + struct scatterlist *src;
> +
> + unsigned int i, len, clen;
> + int ret;
> +
> + int fin = rctx->fini;
> + if (fin)
> + rctx->fini = 0;
> +
> + for_each_sg(req->src, src, nents, i) {
> + src_buf = sg_virt(src);
> + len = sg_dma_len(src);
> +
> + do {
> + if (actx->fill + len > DCP_BUF_SZ)
> + clen = DCP_BUF_SZ - actx->fill;
> + else
> + clen = len;
> +
> + memcpy(in_buf + actx->fill, src_buf, clen);
> + len -= clen;
> + src_buf += clen;
> + actx->fill += clen;
> +
> + /*
> + * If we filled the buffer and still have some
> + * more data, submit the buffer.
> + */
> + if (len && actx->fill == DCP_BUF_SZ) {
> + ret = mxs_dcp_run_sha(req);
> + if (ret)
> + return ret;
> + actx->fill = 0;
> + rctx->init = 0;
> + }
> + } while (len);
> + }
> +
> + if (fin) {
> + rctx->fini = 1;
> +
> + /* Submit whatever is left. */
> + ret = mxs_dcp_run_sha(req);
> + if (ret || !req->result)
> + return ret;
> + actx->fill = 0;
> +
> + /* For some reason, the result is flipped. */
> + for (i = 0; i < halg->digestsize; i++)
> + req->result[i] = digest[halg->digestsize - i - 1];
> + }
> +
> + return 0;
> +}
> +
> +static int dcp_chan_thread_sha(void *data)
> +{
> + struct dcp *sdcp = global_sdcp;
> + const int chan = DCP_CHAN_HASH_SHA;
> +
> + struct crypto_async_request *backlog;
> + struct crypto_async_request *arq;
> +
> + struct dcp_sha_req_ctx *rctx;
> +
> + struct ahash_request *req;
> + int ret, fini;
> +
> + do {
> + __set_current_state(TASK_INTERRUPTIBLE);
> +
> + mutex_lock(&sdcp->mutex[chan]);
> + backlog = crypto_get_backlog(&sdcp->queue[chan]);
> + arq = crypto_dequeue_request(&sdcp->queue[chan]);
> + mutex_unlock(&sdcp->mutex[chan]);
> +
> + if (backlog)
> + backlog->complete(backlog, -EINPROGRESS);
> +
> + if (arq) {
> + req = ahash_request_cast(arq);
> + rctx = ahash_request_ctx(req);
> +
> + ret = dcp_sha_req_to_buf(arq);
> + fini = rctx->fini;
> + arq->complete(arq, ret);
> + if (!fini)
> + continue;
> + }
> +
> + schedule();
> + } while (!kthread_should_stop());
> +
> + return 0;
> +}
> +
> +static int dcp_sha_init(struct ahash_request *req)
> +{
> + struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
> + struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
> +
> + struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
> +
> + /*
> + * Start hashing session. The code below only inits the
> + * hashing session context, nothing more.
> + */
> + memset(actx, 0, sizeof(*actx));
> +
> + if (strcmp(halg->base.cra_name, "sha1") == 0)
> + actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA1;
> + else
> + actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA256;
> +
> + actx->fill = 0;
> + actx->hot = 0;
> + actx->chan = DCP_CHAN_HASH_SHA;
> +
> + mutex_init(&actx->mutex);
> +
> + return 0;
> +}
> +
> +static int dcp_sha_update_fx(struct ahash_request *req, int fini)
> +{
> + struct dcp *sdcp = global_sdcp;
> +
> + struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
> + struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
> + struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
> +
> + int ret;
> +
> + /*
> + * Ignore requests that have no data in them and are not
> + * the trailing requests in the stream of requests.
> + */
> + if (!req->nbytes && !fini)
> + return 0;
> +
> + mutex_lock(&actx->mutex);
> +
> + rctx->fini = fini;
> +
> + if (!actx->hot) {
> + actx->hot = 1;
> + rctx->init = 1;
> + }
> +
> + mutex_lock(&sdcp->mutex[actx->chan]);
> + ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
> + mutex_unlock(&sdcp->mutex[actx->chan]);
> +
> + wake_up_process(sdcp->thread[actx->chan]);
> + mutex_unlock(&actx->mutex);
> +
> + return -EINPROGRESS;
> +}
> +
> +static int dcp_sha_update(struct ahash_request *req)
> +{
> + return dcp_sha_update_fx(req, 0);
> +}
> +
> +static int dcp_sha_final(struct ahash_request *req)
> +{
> + ahash_request_set_crypt(req, NULL, req->result, 0);
> + req->nbytes = 0;
> + return dcp_sha_update_fx(req, 1);
> +}
> +
> +static int dcp_sha_finup(struct ahash_request *req)
> +{
> + return dcp_sha_update_fx(req, 1);
> +}
> +
> +static int dcp_sha_digest(struct ahash_request *req)
> +{
> + int ret;
> +
> + ret = dcp_sha_init(req);
> + if (ret)
> + return ret;
> +
> + return dcp_sha_finup(req);
> +}
> +
> +static int dcp_sha_cra_init(struct crypto_tfm *tfm)
> +{
> + crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
> + sizeof(struct dcp_sha_req_ctx));
> + return 0;
> +}
> +
> +static void dcp_sha_cra_exit(struct crypto_tfm *tfm)
> +{
> +}
> +
> +/* AES 128 ECB and AES 128 CBC */
> +static struct crypto_alg dcp_aes_algs[] = {
> + {
> + .cra_name = "ecb(aes)",
> + .cra_driver_name = "ecb-aes-dcp",
> + .cra_priority = 400,
> + .cra_alignmask = 15,
> + .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER |
> + CRYPTO_ALG_ASYNC |
> + CRYPTO_ALG_NEED_FALLBACK,
> + .cra_init = mxs_dcp_aes_fallback_init,
> + .cra_exit = mxs_dcp_aes_fallback_exit,
> + .cra_blocksize = AES_BLOCK_SIZE,
> + .cra_ctxsize = sizeof(struct dcp_async_ctx),
> + .cra_type = &crypto_ablkcipher_type,
> + .cra_module = THIS_MODULE,
> + .cra_u = {
> + .ablkcipher = {
> + .min_keysize = AES_MIN_KEY_SIZE,
> + .max_keysize = AES_MAX_KEY_SIZE,
> + .setkey = mxs_dcp_aes_setkey,
> + .encrypt = mxs_dcp_aes_ecb_encrypt,
> + .decrypt = mxs_dcp_aes_ecb_decrypt
> + },
> + },
> + }, {
> + .cra_name = "cbc(aes)",
> + .cra_driver_name = "cbc-aes-dcp",
> + .cra_priority = 400,
> + .cra_alignmask = 15,
> + .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER |
> + CRYPTO_ALG_ASYNC |
> + CRYPTO_ALG_NEED_FALLBACK,
> + .cra_init = mxs_dcp_aes_fallback_init,
> + .cra_exit = mxs_dcp_aes_fallback_exit,
> + .cra_blocksize = AES_BLOCK_SIZE,
> + .cra_ctxsize = sizeof(struct dcp_async_ctx),
> + .cra_type = &crypto_ablkcipher_type,
> + .cra_module = THIS_MODULE,
> + .cra_u = {
> + .ablkcipher = {
> + .min_keysize = AES_MIN_KEY_SIZE,
> + .max_keysize = AES_MAX_KEY_SIZE,
> + .setkey = mxs_dcp_aes_setkey,
> + .encrypt = mxs_dcp_aes_cbc_encrypt,
> + .decrypt = mxs_dcp_aes_cbc_decrypt,
> + .ivsize = AES_BLOCK_SIZE,
> + },
> + },
> + },
> +};
> +
> +/* SHA1 */
> +static struct ahash_alg dcp_sha1_alg = {
> + .init = dcp_sha_init,
> + .update = dcp_sha_update,
> + .final = dcp_sha_final,
> + .finup = dcp_sha_finup,
> + .digest = dcp_sha_digest,
> + .halg = {
> + .digestsize = SHA1_DIGEST_SIZE,
> + .base = {
> + .cra_name = "sha1",
> + .cra_driver_name = "sha1-dcp",
> + .cra_priority = 400,
> + .cra_alignmask = 63,
> + .cra_flags = CRYPTO_ALG_ASYNC,
> + .cra_blocksize = SHA1_BLOCK_SIZE,
> + .cra_ctxsize = sizeof(struct dcp_async_ctx),
> + .cra_module = THIS_MODULE,
> + .cra_init = dcp_sha_cra_init,
> + .cra_exit = dcp_sha_cra_exit,
> + },
> + },
> +};
> +
> +/* SHA256 */
> +static struct ahash_alg dcp_sha256_alg = {
> + .init = dcp_sha_init,
> + .update = dcp_sha_update,
> + .final = dcp_sha_final,
> + .finup = dcp_sha_finup,
> + .digest = dcp_sha_digest,
> + .halg = {
> + .digestsize = SHA256_DIGEST_SIZE,
> + .base = {
> + .cra_name = "sha256",
> + .cra_driver_name = "sha256-dcp",
> + .cra_priority = 400,
> + .cra_alignmask = 63,
> + .cra_flags = CRYPTO_ALG_ASYNC,
> + .cra_blocksize = SHA256_BLOCK_SIZE,
> + .cra_ctxsize = sizeof(struct dcp_async_ctx),
> + .cra_module = THIS_MODULE,
> + .cra_init = dcp_sha_cra_init,
> + .cra_exit = dcp_sha_cra_exit,
> + },
> + },
> +};
> +
> +static irqreturn_t mxs_dcp_irq(int irq, void *context)
> +{
> + struct dcp *sdcp = context;
> + uint32_t stat;
> + int i;
> +
> + stat = readl(sdcp->base + MXS_DCP_STAT);
> + stat &= MXS_DCP_STAT_IRQ_MASK;
> + if (!stat)
> + return IRQ_NONE;
> +
> + /* Clear the interrupts. */
> + writel(stat, sdcp->base + MXS_DCP_STAT_CLR);
> +
> + /* Complete the DMA requests that finished. */
> + for (i = 0; i < DCP_MAX_CHANS; i++)
> + if (stat & (1 << i))
> + complete(&sdcp->completion[i]);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int mxs_dcp_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct dcp *sdcp = NULL;
> + int i, ret;
> +
> + struct resource *iores;
> + int dcp_vmi_irq, dcp_irq;
> +
> + mutex_lock(&global_mutex);
> + if (global_sdcp) {
> + dev_err(dev, "Only one DCP instance allowed!\n");
> + ret = -ENODEV;
> + goto err_mutex;
> + }
> +
> + iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + dcp_vmi_irq = platform_get_irq(pdev, 0);
> + dcp_irq = platform_get_irq(pdev, 1);
> + if (dcp_vmi_irq < 0 || dcp_irq < 0) {
> + ret = -EINVAL;
> + goto err_mutex;
> + }
> +
> + sdcp = devm_kzalloc(dev, sizeof(*sdcp), GFP_KERNEL);
> + if (!sdcp) {
> + ret = -ENOMEM;
> + goto err_mutex;
> + }
> +
> + sdcp->dev = dev;
> + sdcp->base = devm_ioremap_resource(dev, iores);
> + if (IS_ERR(sdcp->base)) {
> + ret = PTR_ERR(sdcp->base);
> + goto err_mutex;
> + }
> +
> + ret = devm_request_irq(dev, dcp_vmi_irq, mxs_dcp_irq, 0,
> + "dcp-vmi-irq", sdcp);
> + if (ret) {
> + dev_err(dev, "Failed to claim DCP VMI IRQ!\n");
> + goto err_mutex;
> + }
> +
> + ret = devm_request_irq(dev, dcp_irq, mxs_dcp_irq, 0,
> + "dcp-irq", sdcp);
> + if (ret) {
> + dev_err(dev, "Failed to claim DCP IRQ!\n");
> + goto err_mutex;
> + }
> +
> + /* Allocate coherent helper block. */
> + sdcp->coh = kzalloc(sizeof(struct dcp_coherent_block), GFP_KERNEL);
> + if (!sdcp->coh) {
> + dev_err(dev, "Error allocating coherent block\n");
> + ret = -ENOMEM;
> + goto err_mutex;
> + }
> +
> + /* Restart the DCP block. */
> + stmp_reset_block(sdcp->base);
> +
> + /* Initialize control register. */
> + writel(MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES |
> + MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING | 0xf,
> + sdcp->base + MXS_DCP_CTRL);
> +
> + /* Enable all DCP DMA channels. */
> + writel(MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK,
> + sdcp->base + MXS_DCP_CHANNELCTRL);
> +
> + /*
> + * We do not enable context switching. Give the context buffer a
> + * pointer to an illegal address so if context switching is
> + * inadvertantly enabled, the DCP will return an error instead of
> + * trashing good memory. The DCP DMA cannot access ROM, so any ROM
> + * address will do.
> + */
> + writel(0xffff0000, sdcp->base + MXS_DCP_CONTEXT);
> + for (i = 0; i < DCP_MAX_CHANS; i++)
> + writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(i));
> + writel(0xffffffff, sdcp->base + MXS_DCP_STAT_CLR);
> +
> + global_sdcp = sdcp;
> +
> + platform_set_drvdata(pdev, sdcp);
> +
> + for (i = 0; i < DCP_MAX_CHANS; i++) {
> + mutex_init(&sdcp->mutex[i]);
> + init_completion(&sdcp->completion[i]);
> + crypto_init_queue(&sdcp->queue[i], 50);
> + }
> +
> + /* Create the SHA and AES handler threads. */
> + sdcp->thread[DCP_CHAN_HASH_SHA] = kthread_run(dcp_chan_thread_sha,
> + NULL, "mxs_dcp_chan/sha");
> + if (IS_ERR(sdcp->thread[DCP_CHAN_HASH_SHA])) {
> + dev_err(dev, "Error starting SHA thread!\n");
> + ret = PTR_ERR(sdcp->thread[DCP_CHAN_HASH_SHA]);
> + goto err_free_coherent;
> + }
> +
> + sdcp->thread[DCP_CHAN_CRYPTO] = kthread_run(dcp_chan_thread_aes,
> + NULL, "mxs_dcp_chan/aes");
> + if (IS_ERR(sdcp->thread[DCP_CHAN_CRYPTO])) {
> + dev_err(dev, "Error starting SHA thread!\n");
> + ret = PTR_ERR(sdcp->thread[DCP_CHAN_CRYPTO]);
> + goto err_destroy_sha_thread;
> + }
> +
> + /* Register the various crypto algorithms. */
> + sdcp->caps = readl(sdcp->base + MXS_DCP_CAPABILITY1);
> +
> + if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128) {
> + ret = crypto_register_algs(dcp_aes_algs,
> + ARRAY_SIZE(dcp_aes_algs));
> + if (ret) {
> + /* Failed to register algorithm. */
> + dev_err(dev, "Failed to register AES crypto!\n");
> + goto err_destroy_aes_thread;
> + }
> + }
> +
> + if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1) {
> + ret = crypto_register_ahash(&dcp_sha1_alg);
> + if (ret) {
> + dev_err(dev, "Failed to register %s hash!\n",
> + dcp_sha1_alg.halg.base.cra_name);
> + goto err_unregister_aes;
> + }
> + }
> +
> + if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256) {
> + ret = crypto_register_ahash(&dcp_sha256_alg);
> + if (ret) {
> + dev_err(dev, "Failed to register %s hash!\n",
> + dcp_sha256_alg.halg.base.cra_name);
> + goto err_unregister_sha1;
> + }
> + }
> +
> + return 0;
> +
> +err_unregister_sha1:
> + if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
> + crypto_unregister_ahash(&dcp_sha1_alg);
> +
> +err_unregister_aes:
> + if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
> + crypto_unregister_algs(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
> +
> +err_destroy_aes_thread:
> + kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
> +
> +err_destroy_sha_thread:
> + kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
> +
> +err_free_coherent:
> + kfree(sdcp->coh);
> +err_mutex:
> + mutex_unlock(&global_mutex);
> + return ret;
> +}
> +
> +static int mxs_dcp_remove(struct platform_device *pdev)
> +{
> + struct dcp *sdcp = platform_get_drvdata(pdev);
> +
> + kfree(sdcp->coh);
> +
> + if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256)
> + crypto_unregister_ahash(&dcp_sha256_alg);
> +
> + if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
> + crypto_unregister_ahash(&dcp_sha1_alg);
> +
> + if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
> + crypto_unregister_algs(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
> +
> + kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
> + kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
> +
> + platform_set_drvdata(pdev, NULL);
> +
> + mutex_lock(&global_mutex);
> + global_sdcp = NULL;
> + mutex_unlock(&global_mutex);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id mxs_dcp_dt_ids[] = {
> + { .compatible = "fsl,imx23-dcp", .data = NULL, },
> + { .compatible = "fsl,imx28-dcp", .data = NULL, },
> + { /* sentinel */ }
> +};
> +
> +MODULE_DEVICE_TABLE(of, mxs_dcp_dt_ids);
> +
> +static struct platform_driver mxs_dcp_driver = {
> + .probe = mxs_dcp_probe,
> + .remove = mxs_dcp_remove,
> + .driver = {
> + .name = "mxs-dcp",
> + .owner = THIS_MODULE,
> + .of_match_table = mxs_dcp_dt_ids,
> + },
> +};
> +
> +module_platform_driver(mxs_dcp_driver);
> +
> +MODULE_AUTHOR("Marek Vasut <marex at denx.de>");
> +MODULE_DESCRIPTION("Freescale MXS DCP Driver");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:mxs-dcp");
> --
> 1.8.4.2
>
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