by Vladimir Zapolskiy

[permalink] [raw]

Subject: Re: [PATCH v5 4/4] crypto: Add Allwinner Security System crypto accelerator

Hi Corentin,

On 21.10.2014 19:25, Corentin LABBE wrote:
> On 10/21/14 01:28, Vladimir Zapolskiy wrote:
>> Hello LABBE,
>>
>> On 19.10.2014 17:16, LABBE Corentin wrote:
>>> Add support for the Security System included in Allwinner SoC A20.
>>> The Security System is a hardware cryptographic accelerator that support AES/MD5/SHA1/DES/3DES/PRNG algorithms.
>>>
> []
>>> +
>>> + /* If we have only one SG, we can use kmap_atomic */
>>> + if (sg_next(in_sg) == NULL && sg_next(out_sg) == NULL)
>>> + return sunxi_ss_aes_poll_atomic(areq);
>>
>> for clarity it might be better to move all "mutex_unlock(&ss->lock)"
>> calls from sunxi_ss_aes_poll_atomic() body right to here.
>>
>
> Ok
> I have moved all mutex_unlock/writel(0, SS_CTL) at the end of function, it is cleaner now.

please check that sunxi_ss_aes_poll_atomic() has no more mutex_unlock()
calls inside it.

With best wishes,
Vladimir

>>> +
>>> +};
>>> +
>>> +static int sunxi_ss_probe(struct platform_device *pdev)
>>> +{
>>> + struct resource *res;
>>> + u32 v;
>>> + int err;
>>> + unsigned long cr;
>>> + const unsigned long cr_ahb = 24 * 1000 * 1000;
>>> + const unsigned long cr_mod = 150 * 1000 * 1000;
>>> +
>>> + if (!pdev->dev.of_node)
>>> + return -ENODEV;
>>> +
>>> + ss = devm_kzalloc(&pdev->dev, sizeof(*ss), GFP_KERNEL);
>>> + if (ss == NULL)
>>> + return -ENOMEM;
>>
>> Why do you dynamically allocate memory for "struct sunxi_ss_ctx *ss"?
>> Since you have a single global pointer, it makes sense to declare
>> "struct sunxi_ss_ctx ss" statically instead.
>>
>> And even a better solution is to remove a single global pointer.
>
> All other crypto driver I have read use a global structure and it made things easy.
> Thanks to M. Ripard that pointed to me the talitos driver that solve the global device pointer by using alg template and container_of().
>
> But since I think there will never 2 Security System at the same time on the same SoC, I do not know if it is worth the cost to add more complexity just to remove a pointer.
>
>>
>>> +
>>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>>> + ss->base = devm_ioremap_resource(&pdev->dev, res);
>>> + if (IS_ERR(ss->base)) {
>>> + dev_err(&pdev->dev, "Cannot request MMIO\n");
>>> + return PTR_ERR(ss->base);
>>> + }
>>> +
>>> + ss->ssclk = devm_clk_get(&pdev->dev, "mod");
>>> + if (IS_ERR(ss->ssclk)) {
>>> + err = PTR_ERR(ss->ssclk);
>>> + dev_err(&pdev->dev, "Cannot get SS clock err=%d\n", err);
>>> + return err;
>>> + }
>>> + dev_dbg(&pdev->dev, "clock ss acquired\n");
>>> +
>>> + ss->busclk = devm_clk_get(&pdev->dev, "ahb");
>>> + if (IS_ERR(ss->busclk)) {
>>> + err = PTR_ERR(ss->busclk);
>>> + dev_err(&pdev->dev, "Cannot get AHB SS clock err=%d\n", err);
>>> + return err;
>>> + }
>>> + dev_dbg(&pdev->dev, "clock ahb_ss acquired\n");
>>> +
>>> + /* Enable both clocks */
>>> + err = clk_prepare_enable(ss->busclk);
>>> + if (err != 0) {
>>> + dev_err(&pdev->dev, "Cannot prepare_enable busclk\n");
>>> + return err;
>>> + }
>>> + err = clk_prepare_enable(ss->ssclk);
>>> + if (err != 0) {
>>> + dev_err(&pdev->dev, "Cannot prepare_enable ssclk\n");
>>> + clk_disable_unprepare(ss->busclk);
>>
>> goto somewhere to the end of the function?
>
> OK
>
>>
>>> + return err;
>>> + }
>>> +
>>> + /*
>>> + * Check that clock have the correct rates gived in the datasheet
>>> + * Try to set the clock to the maximum allowed
>>> + */
>>> + err = clk_set_rate(ss->ssclk, cr_mod);
>>> + if (err != 0) {
>>> + dev_err(&pdev->dev, "Cannot set clock rate to ssclk\n");
>>> + clk_disable_unprepare(ss->ssclk);
>>> + clk_disable_unprepare(ss->busclk);
>>
>> goto "error_md5"?
>
> Ok
>
>>
>>> + return err;
>>> + }
>>> +
>>> + cr = clk_get_rate(ss->busclk);
>>> + if (cr >= cr_ahb)
>>> + dev_dbg(&pdev->dev, "Clock bus %lu (%lu MHz) (must be >= %lu)\n",
>>> + cr, cr / 1000000, cr_ahb);
>>> + else
>>> + dev_warn(&pdev->dev, "Clock bus %lu (%lu MHz) (must be >= %lu)\n",
>>> + cr, cr / 1000000, cr_ahb);
>>
>> See next comment.
>>
>>> + cr = clk_get_rate(ss->ssclk);
>>> + if (cr <= cr_mod)
>>> + if (cr < cr_mod)
>>> + dev_info(&pdev->dev, "Clock ss %lu (%lu MHz) (must be <= %lu)\n",
>>> + cr, cr / 1000000, cr_mod);
>>> + else
>>> + dev_dbg(&pdev->dev, "Clock ss %lu (%lu MHz) (must be <= %lu)\n",
>>> + cr, cr / 1000000, cr_mod);
>>> + else
>>> + dev_warn(&pdev->dev, "Clock ss is at %lu (%lu MHz) (must be <= %lu)\n",
>>> + cr, cr / 1000000, cr_mod);
>>
>> The management of kernel log levels looks pretty strange. As far as I
>> understand there is no error on any clock rate, I'd recommend to keep
>> only one information message.
>>
>
> If clock rate are below the recommended value, the only impact I found was bad performance.
> So it explain the warn and no error. (yes the info must be warn, ...fixed)
>
> But I will put comment for explain that.
>
>>> + /*
>>> + * Datasheet named it "Die Bonding ID"
>>> + * I expect to be a sort of Security System Revision number.
>>> + * Since the A80 seems to have an other version of SS
>>> + * this info could be useful
>>> + */
>>> + writel(SS_ENABLED, ss->base + SS_CTL);
>>> + v = readl(ss->base + SS_CTL);
>>> + v >>= 16;
>>> + v &= 0x07;
>>> + dev_info(&pdev->dev, "Die ID %d\n", v);
>>> + writel(0, ss->base + SS_CTL);
>>> +
>>> + ss->dev = &pdev->dev;
>>> +
>>> + mutex_init(&ss->lock);
>>> + mutex_init(&ss->bufin_lock);
>>> + mutex_init(&ss->bufout_lock);
>>> +
>>> + err = crypto_register_ahash(&sunxi_md5_alg);
>>> + if (err)
>>> + goto error_md5;
>>> + err = crypto_register_ahash(&sunxi_sha1_alg);
>>> + if (err)
>>> + goto error_sha1;
>>> + err = crypto_register_algs(sunxi_cipher_algs,
>>> + ARRAY_SIZE(sunxi_cipher_algs));
>>> + if (err)
>>> + goto error_ciphers;
>>> +
>>> + return 0;
>>> +error_ciphers:
>>> + crypto_unregister_ahash(&sunxi_sha1_alg);
>>> +error_sha1:
>>> + crypto_unregister_ahash(&sunxi_md5_alg);
>>> +error_md5:
>>> + clk_disable_unprepare(ss->ssclk);
>>> + clk_disable_unprepare(ss->busclk);
>>> + return err;
>>> +}
>>> +
>>> +static int __exit sunxi_ss_remove(struct platform_device *pdev)
>>> +{
>>> + if (!pdev->dev.of_node)
>>> + return 0;
>>
>> Redundant check.
>>
>
> Ok
>
>>
>>
>> --
>> With best wishes,
>> Vladimir
>>
>
> Thanks for the review
>
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>

2014-10-21 19:15:11

by Maxime Ripard

[permalink] [raw]

Subject: Re: [PATCH v5 4/4] crypto: Add Allwinner Security System crypto accelerator

Hi Corentin,

Thanks for resending it.

On Sun, Oct 19, 2014 at 04:16:22PM +0200, LABBE Corentin wrote:
> Add support for the Security System included in Allwinner SoC A20.
> The Security System is a hardware cryptographic accelerator that support AES/MD5/SHA1/DES/3DES/PRNG algorithms.
>
> Signed-off-by: LABBE Corentin <[email protected]>
> ---
> drivers/crypto/Kconfig | 17 ++
> drivers/crypto/Makefile | 1 +
> drivers/crypto/sunxi-ss/Makefile | 2 +
> drivers/crypto/sunxi-ss/sunxi-ss-cipher.c | 489 ++++++++++++++++++++++++++++++
> drivers/crypto/sunxi-ss/sunxi-ss-core.c | 318 +++++++++++++++++++
> drivers/crypto/sunxi-ss/sunxi-ss-hash.c | 445 +++++++++++++++++++++++++++
> drivers/crypto/sunxi-ss/sunxi-ss.h | 193 ++++++++++++
> 7 files changed, 1465 insertions(+)
> create mode 100644 drivers/crypto/sunxi-ss/Makefile
> create mode 100644 drivers/crypto/sunxi-ss/sunxi-ss-cipher.c
> create mode 100644 drivers/crypto/sunxi-ss/sunxi-ss-core.c
> create mode 100644 drivers/crypto/sunxi-ss/sunxi-ss-hash.c
> create mode 100644 drivers/crypto/sunxi-ss/sunxi-ss.h
>
> diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
> index 2fb0fdf..9ba9759 100644
> --- a/drivers/crypto/Kconfig
> +++ b/drivers/crypto/Kconfig
> @@ -436,4 +436,21 @@ config CRYPTO_DEV_QCE
> hardware. To compile this driver as a module, choose M here. The
> module will be called qcrypto.
>
> +config CRYPTO_DEV_SUNXI_SS
> + tristate "Support for Allwinner Security System cryptographic accelerator"
> + depends on ARCH_SUNXI
> + select CRYPTO_MD5
> + select CRYPTO_SHA1
> + select CRYPTO_AES
> + select CRYPTO_DES
> + select CRYPTO_BLKCIPHER
> + help
> + Some Allwinner SoC have a crypto accelerator named
> + Security System. Select this if you want to use it.
> + The Security System handle AES/DES/3DES ciphers in CBC mode
> + and SHA1 and MD5 hash algorithms.
> +
> + To compile this driver as a module, choose M here: the module
> + will be called sunxi-ss.
> +
> endif # CRYPTO_HW
> diff --git a/drivers/crypto/Makefile b/drivers/crypto/Makefile
> index 3924f93..856545c 100644
> --- a/drivers/crypto/Makefile
> +++ b/drivers/crypto/Makefile
> @@ -25,3 +25,4 @@ obj-$(CONFIG_CRYPTO_DEV_TALITOS) += talitos.o
> obj-$(CONFIG_CRYPTO_DEV_UX500) += ux500/
> obj-$(CONFIG_CRYPTO_DEV_QAT) += qat/
> obj-$(CONFIG_CRYPTO_DEV_QCE) += qce/
> +obj-$(CONFIG_CRYPTO_DEV_SUNXI_SS) += sunxi-ss/
> diff --git a/drivers/crypto/sunxi-ss/Makefile b/drivers/crypto/sunxi-ss/Makefile
> new file mode 100644
> index 0000000..8bb287d
> --- /dev/null
> +++ b/drivers/crypto/sunxi-ss/Makefile
> @@ -0,0 +1,2 @@
> +obj-$(CONFIG_CRYPTO_DEV_SUNXI_SS) += sunxi-ss.o
> +sunxi-ss-y += sunxi-ss-core.o sunxi-ss-hash.o sunxi-ss-cipher.o
> diff --git a/drivers/crypto/sunxi-ss/sunxi-ss-cipher.c b/drivers/crypto/sunxi-ss/sunxi-ss-cipher.c
> new file mode 100644
> index 0000000..8d0416e
> --- /dev/null
> +++ b/drivers/crypto/sunxi-ss/sunxi-ss-cipher.c
> @@ -0,0 +1,489 @@
> +/*
> + * sunxi-ss-cipher.c - hardware cryptographic accelerator for Allwinner A20 SoC
> + *
> + * Copyright (C) 2013-2014 Corentin LABBE <[email protected]>
> + *
> + * This file add support for AES cipher with 128,192,256 bits
> + * keysize in CBC mode.
> + * Add support also for DES and 3DES in CBC mode.
> + *
> + * You could find the datasheet in Documentation/arm/sunxi/README
> + *
> + * 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.
> + */
> +#include "sunxi-ss.h"
> +
> +extern struct sunxi_ss_ctx *ss;
> +
> +static int sunxi_ss_cipher(struct ablkcipher_request *areq, u32 mode)
> +{
> + struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(areq);
> + struct sunxi_tfm_ctx *op = crypto_ablkcipher_ctx(tfm);
> + const char *cipher_type;
> +
> + if (areq->nbytes == 0)
> + return 0;
> +
> + if (areq->info == NULL) {
> + dev_err(ss->dev, "ERROR: Empty IV\n");
> + return -EINVAL;
> + }
> +
> + if (areq->src == NULL || areq->dst == NULL) {
> + dev_err(ss->dev, "ERROR: Some SGs are NULL\n");
> + return -EINVAL;
> + }
> +
> + cipher_type = crypto_tfm_alg_name(crypto_ablkcipher_tfm(tfm));
> +
> + if (strcmp("cbc(aes)", cipher_type) == 0) {
> + mode |= SS_OP_AES | SS_CBC | SS_ENABLED | op->keymode;
> + return sunxi_ss_aes_poll(areq, mode);
> + }
> +
> + if (strcmp("cbc(des)", cipher_type) == 0) {
> + mode |= SS_OP_DES | SS_CBC | SS_ENABLED | op->keymode;
> + return sunxi_ss_des_poll(areq, mode);
> + }
> +
> + if (strcmp("cbc(des3_ede)", cipher_type) == 0) {
> + mode |= SS_OP_3DES | SS_CBC | SS_ENABLED | op->keymode;
> + return sunxi_ss_des_poll(areq, mode);
> + }
> +
> + dev_err(ss->dev, "ERROR: Cipher %s not handled\n", cipher_type);
> + return -EINVAL;
> +}
> +
> +int sunxi_ss_cipher_encrypt(struct ablkcipher_request *areq)
> +{
> + return sunxi_ss_cipher(areq, SS_ENCRYPTION);
> +}
> +
> +int sunxi_ss_cipher_decrypt(struct ablkcipher_request *areq)
> +{
> + return sunxi_ss_cipher(areq, SS_DECRYPTION);
> +}
> +
> +int sunxi_ss_cipher_init(struct crypto_tfm *tfm)
> +{
> + struct sunxi_tfm_ctx *op = crypto_tfm_ctx(tfm);
> +
> + memset(op, 0, sizeof(struct sunxi_tfm_ctx));
> + return 0;
> +}
> +
> +/*
> + * Optimized function for the case where we have only one SG,
> + * so we can use kmap_atomic
> + */
> +static int sunxi_ss_aes_poll_atomic(struct ablkcipher_request *areq)
> +{
> + u32 spaces;
> + struct scatterlist *in_sg = areq->src;
> + struct scatterlist *out_sg = areq->dst;
> + void *src_addr;
> + void *dst_addr;
> + unsigned int ileft = areq->nbytes;
> + unsigned int oleft = areq->nbytes;
> + unsigned int todo;
> + u32 *src32;
> + u32 *dst32;
> + u32 rx_cnt = 32;
> + u32 tx_cnt = 0;
> + int i;
> +
> + src_addr = kmap_atomic(sg_page(in_sg)) + in_sg->offset;

Where does this scatter_list is coming from? Can it even be allocated
in highmem?

> + if (src_addr == NULL) {
> + dev_err(ss->dev, "kmap_atomic error for src SG\n");
> + writel(0, ss->base + SS_CTL);
> + mutex_unlock(&ss->lock);
> + return -EINVAL;
> + }
> +
> + dst_addr = kmap_atomic(sg_page(out_sg)) + out_sg->offset;
> + if (dst_addr == NULL) {
> + dev_err(ss->dev, "kmap_atomic error for dst SG\n");
> + writel(0, ss->base + SS_CTL);
> + kunmap_atomic(src_addr);
> + mutex_unlock(&ss->lock);
> + return -EINVAL;

Please use gotos in your error path.

> + }
> +
> + src32 = (u32 *)src_addr;
> + dst32 = (u32 *)dst_addr;
> + ileft = areq->nbytes / 4;
> + oleft = areq->nbytes / 4;
> + i = 0;
> + do {
> + if (ileft > 0 && rx_cnt > 0) {
> + todo = min(rx_cnt, ileft);
> + ileft -= todo;
> + do {
> + writel_relaxed(*src32++,

Please put some braces around that referencing/increment.

> + ss->base +
> + SS_RXFIFO);
> + todo--;
> + } while (todo > 0);
> + }
> + if (tx_cnt > 0) {
> + todo = min(tx_cnt, oleft);
> + oleft -= todo;
> + do {
> + *dst32++ = readl_relaxed(ss->base +
> + SS_TXFIFO);
> + todo--;
> + } while (todo > 0);
> + }
> + spaces = readl_relaxed(ss->base + SS_FCSR);
> + rx_cnt = SS_RXFIFO_SPACES(spaces);
> + tx_cnt = SS_TXFIFO_SPACES(spaces);
> + } while (oleft > 0);
> + writel(0, ss->base + SS_CTL);
> + kunmap_atomic(src_addr);
> + kunmap_atomic(dst_addr);
> + mutex_unlock(&ss->lock);

You never took that mutex in that function...

> + return 0;
> +}
> +
> +int sunxi_ss_aes_poll(struct ablkcipher_request *areq, u32 mode)
> +{
> + u32 spaces;
> + struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(areq);
> + struct sunxi_tfm_ctx *op = crypto_ablkcipher_ctx(tfm);
> + unsigned int ivsize = crypto_ablkcipher_ivsize(tfm);
> + /* when activating SS, the default FIFO space is 32 */
> + u32 rx_cnt = 32;
> + u32 tx_cnt = 0;
> + u32 v;
> + int i;
> + struct scatterlist *in_sg = areq->src;
> + struct scatterlist *out_sg = areq->dst;
> + void *src_addr;
> + void *dst_addr;
> + unsigned int ileft = areq->nbytes;
> + unsigned int oleft = areq->nbytes;
> + unsigned int sgileft = areq->src->length;
> + unsigned int sgoleft = areq->dst->length;
> + unsigned int todo;
> + u32 *src32;
> + u32 *dst32;
> +
> + mutex_lock(&ss->lock);
> +
> + for (i = 0; i < op->keylen; i += 4)
> + writel(*(op->key + i/4), ss->base + SS_KEY0 + i);
> +
> + if (areq->info != NULL) {
> + for (i = 0; i < 4 && i < ivsize / 4; i++) {
> + v = *(u32 *)(areq->info + i * 4);
> + writel(v, ss->base + SS_IV0 + i * 4);
> + }
> + }
> + writel(mode, ss->base + SS_CTL);
> +
> + /* If we have only one SG, we can use kmap_atomic */
> + if (sg_next(in_sg) == NULL && sg_next(out_sg) == NULL)
> + return sunxi_ss_aes_poll_atomic(areq);
> +
> + /*
> + * If we have more than one SG, we cannot use kmap_atomic since
> + * we hold the mapping too long
> + */
> + src_addr = kmap(sg_page(in_sg)) + in_sg->offset;
> + if (src_addr == NULL) {
> + dev_err(ss->dev, "KMAP error for src SG\n");
> + mutex_unlock(&ss->lock);
> + return -EINVAL;
> + }
> + dst_addr = kmap(sg_page(out_sg)) + out_sg->offset;
> + if (dst_addr == NULL) {
> + kunmap(sg_page(in_sg));
> + dev_err(ss->dev, "KMAP error for dst SG\n");
> + mutex_unlock(&ss->lock);
> + return -EINVAL;
> + }
> + src32 = (u32 *)src_addr;
> + dst32 = (u32 *)dst_addr;
> + ileft = areq->nbytes / 4;
> + oleft = areq->nbytes / 4;
> + sgileft = in_sg->length / 4;
> + sgoleft = out_sg->length / 4;
> + do {
> + spaces = readl_relaxed(ss->base + SS_FCSR);
> + rx_cnt = SS_RXFIFO_SPACES(spaces);
> + tx_cnt = SS_TXFIFO_SPACES(spaces);
> + todo = min3(rx_cnt, ileft, sgileft);
> + if (todo > 0) {
> + ileft -= todo;
> + sgileft -= todo;
> + }
> + while (todo > 0) {
> + writel_relaxed(*src32++, ss->base + SS_RXFIFO);
> + todo--;
> + }
> + if (in_sg != NULL && sgileft == 0 && ileft > 0) {
> + kunmap(sg_page(in_sg));
> + in_sg = sg_next(in_sg);
> + while (in_sg != NULL && in_sg->length == 0)
> + in_sg = sg_next(in_sg);
> + if (in_sg != NULL && ileft > 0) {
> + src_addr = kmap(sg_page(in_sg)) + in_sg->offset;
> + if (src_addr == NULL) {
> + dev_err(ss->dev, "ERROR: KMAP for src SG\n");
> + mutex_unlock(&ss->lock);
> + return -EINVAL;
> + }
> + src32 = src_addr;
> + sgileft = in_sg->length / 4;
> + }
> + }
> + /* do not test oleft since when oleft == 0 we have finished */
> + todo = min3(tx_cnt, oleft, sgoleft);
> + if (todo > 0) {
> + oleft -= todo;
> + sgoleft -= todo;
> + }
> + while (todo > 0) {
> + *dst32++ = readl_relaxed(ss->base + SS_TXFIFO);
> + todo--;
> + }
> + if (out_sg != NULL && sgoleft == 0 && oleft >= 0) {
> + kunmap(sg_page(out_sg));
> + out_sg = sg_next(out_sg);
> + while (out_sg != NULL && out_sg->length == 0)
> + out_sg = sg_next(out_sg);
> + if (out_sg != NULL && oleft > 0) {
> + dst_addr = kmap(sg_page(out_sg)) +
> + out_sg->offset;
> + if (dst_addr == NULL) {
> + dev_err(ss->dev, "KMAP error\n");
> + mutex_unlock(&ss->lock);
> + return -EINVAL;
> + }
> + dst32 = dst_addr;
> + sgoleft = out_sg->length / 4;
> + }
> + }
> + } while (oleft > 0);
> +
> + writel_relaxed(0, ss->base + SS_CTL);
> + mutex_unlock(&ss->lock);
> + return 0;
> +}
> +
> +/*
> + * Pure CPU way of doing DES/3DES with SS
> + * Since DES and 3DES SGs could be smaller than 4 bytes, I use sg_copy_to_buffer
> + * for "linearize" them.
> + * The problem with that is that I alloc (2 x areq->nbytes) for buf_in/buf_out
> + * TODO: change this system, I need to support other mode than CBC where len
> + * is not a multiple of 4 and the hack of linearize use too much memory
> + * SGsrc -> buf_in -> SS -> buf_out -> SGdst
> + */
> +int sunxi_ss_des_poll(struct ablkcipher_request *areq, u32 mode)
> +{
> + u32 value, spaces;
> + size_t nb_in_sg_tx, nb_in_sg_rx;
> + size_t ir, it;
> + struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(areq);
> + struct sunxi_tfm_ctx *op = crypto_ablkcipher_ctx(tfm);
> + unsigned int ivsize = crypto_ablkcipher_ivsize(tfm);
> + u32 tx_cnt = 0;
> + u32 rx_cnt = 0;
> + u32 v;
> + int i;
> + int no_chunk = 1;
> + struct scatterlist *in_sg = areq->src;
> + struct scatterlist *out_sg = areq->dst;
> +
> + /*
> + * if we have only SGs with size multiple of 4,
> + * we can use the SS AES function
> + */
> + while (in_sg != NULL && no_chunk == 1) {
> + if ((in_sg->length % 4) != 0)
> + no_chunk = 0;
> + in_sg = sg_next(in_sg);
> + }
> + while (out_sg != NULL && no_chunk == 1) {
> + if ((out_sg->length % 4) != 0)
> + no_chunk = 0;
> + out_sg = sg_next(out_sg);
> + }
> +
> + if (no_chunk == 1)
> + return sunxi_ss_aes_poll(areq, mode);
> +
> + in_sg = areq->src;
> + out_sg = areq->dst;
> +
> + nb_in_sg_rx = sg_nents(in_sg);
> + nb_in_sg_tx = sg_nents(out_sg);
> +
> + /*
> + * buf_in and buf_out are allocated only one time
> + * then we keep the buffer until driver end
> + * the allocation can only grow more
> + * we do not reduce it for simplification
> + */
> + mutex_lock(&ss->bufin_lock);
> + if (ss->buf_in == NULL) {
> + ss->buf_in = kmalloc(areq->nbytes, GFP_KERNEL);
> + ss->buf_in_size = areq->nbytes;
> + } else {
> + if (areq->nbytes > ss->buf_in_size) {
> + kfree(ss->buf_in);
> + ss->buf_in = kmalloc(areq->nbytes, GFP_KERNEL);
> + ss->buf_in_size = areq->nbytes;
> + }
> + }
> + if (ss->buf_in == NULL) {
> + ss->buf_in_size = 0;
> + mutex_unlock(&ss->bufin_lock);
> + dev_err(ss->dev, "Unable to allocate pages.\n");
> + return -ENOMEM;
> + }
> + mutex_lock(&ss->bufout_lock);

What are these two mutexes used for? It looks like you're only using
them in this function.

What would prevent you from just using the "main" lock like you did
for the AES?

> + if (ss->buf_out == NULL) {
> + ss->buf_out = kmalloc(areq->nbytes, GFP_KERNEL);
> + if (ss->buf_out == NULL) {
> + ss->buf_out_size = 0;
> + mutex_unlock(&ss->bufin_lock);
> + mutex_unlock(&ss->bufout_lock);
> + dev_err(ss->dev, "Unable to allocate pages.\n");
> + return -ENOMEM;
> + }
> + ss->buf_out_size = areq->nbytes;
> + } else {
> + if (areq->nbytes > ss->buf_out_size) {
> + kfree(ss->buf_out);
> + ss->buf_out = kmalloc(areq->nbytes, GFP_KERNEL);
> + if (ss->buf_out == NULL) {
> + ss->buf_out_size = 0;
> + mutex_unlock(&ss->bufin_lock);
> + mutex_unlock(&ss->bufout_lock);
> + dev_err(ss->dev, "Unable to allocate pages.\n");
> + return -ENOMEM;
> + }
> + ss->buf_out_size = areq->nbytes;
> + }
> + }
> +
> + sg_copy_to_buffer(areq->src, nb_in_sg_rx, ss->buf_in, areq->nbytes);
> +
> + ir = 0;
> + it = 0;
> + mutex_lock(&ss->lock);
> +
> + for (i = 0; i < op->keylen; i += 4)
> + writel(*(op->key + i/4), ss->base + SS_KEY0 + i);
> + if (areq->info != NULL) {
> + for (i = 0; i < 4 && i < ivsize / 4; i++) {
> + v = *(u32 *)(areq->info + i * 4);
> + writel(v, ss->base + SS_IV0 + i * 4);
> + }
> + }
> + writel(mode, ss->base + SS_CTL);
> +
> + do {
> + if (rx_cnt == 0 || tx_cnt == 0) {
> + spaces = readl(ss->base + SS_FCSR);
> + rx_cnt = SS_RXFIFO_SPACES(spaces);
> + tx_cnt = SS_TXFIFO_SPACES(spaces);
> + }
> + if (rx_cnt > 0 && ir < areq->nbytes) {
> + do {
> + value = *(u32 *)(ss->buf_in + ir);
> + writel(value, ss->base + SS_RXFIFO);
> + ir += 4;
> + rx_cnt--;
> + } while (rx_cnt > 0 && ir < areq->nbytes);
> + }
> + if (tx_cnt > 0 && it < areq->nbytes) {
> + do {
> + value = readl(ss->base + SS_TXFIFO);
> + *(u32 *)(ss->buf_out + it) = value;
> + it += 4;
> + tx_cnt--;
> + } while (tx_cnt > 0 && it < areq->nbytes);
> + }
> + if (ir == areq->nbytes) {
> + mutex_unlock(&ss->bufin_lock);

If tx_cnt <= 0 and it < areq->nbytes, your loop will stop, and you'll
not release the mutex.

> + ir++;
> + }
> + } while (it < areq->nbytes);
> +
> + writel(0, ss->base + SS_CTL);
> + mutex_unlock(&ss->lock);
> +
> + /*
> + * a simple optimization, since we dont need the hardware for this copy
> + * we release the lock and do the copy. With that we gain 5/10% perf
> + */
> + sg_copy_from_buffer(areq->dst, nb_in_sg_tx, ss->buf_out, areq->nbytes);
> +
> + mutex_unlock(&ss->bufout_lock);
> + return 0;
> +}
> +
> +/* check and set the AES key, prepare the mode to be used */
> +int sunxi_ss_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
> + unsigned int keylen)
> +{
> + struct sunxi_tfm_ctx *op = crypto_ablkcipher_ctx(tfm);
> +
> + switch (keylen) {
> + case 128 / 8:
> + op->keymode = SS_AES_128BITS;
> + break;
> + case 192 / 8:
> + op->keymode = SS_AES_192BITS;
> + break;
> + case 256 / 8:
> + op->keymode = SS_AES_256BITS;
> + break;
> + default:
> + dev_err(ss->dev, "ERROR: Invalid keylen %u\n", keylen);
> + crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
> + return -EINVAL;
> + }
> + op->keylen = keylen;
> + memcpy(op->key, key, keylen);
> + return 0;
> +}
> +
> +/* check and set the DES key, prepare the mode to be used */
> +int sunxi_ss_des_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
> + unsigned int keylen)
> +{
> + struct sunxi_tfm_ctx *op = crypto_ablkcipher_ctx(tfm);
> +
> + if (keylen != DES_KEY_SIZE) {
> + dev_err(ss->dev, "Invalid keylen %u\n", keylen);
> + crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
> + return -EINVAL;
> + }
> + op->keylen = keylen;
> + memcpy(op->key, key, keylen);
> + return 0;
> +}
> +
> +/* check and set the 3DES key, prepare the mode to be used */
> +int sunxi_ss_des3_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
> + unsigned int keylen)
> +{
> + struct sunxi_tfm_ctx *op = crypto_ablkcipher_ctx(tfm);
> +
> + if (keylen != 3 * DES_KEY_SIZE) {
> + dev_err(ss->dev, "Invalid keylen %u\n", keylen);
> + crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
> + return -EINVAL;
> + }
> + op->keylen = keylen;
> + memcpy(op->key, key, keylen);
> + return 0;
> +}
> diff --git a/drivers/crypto/sunxi-ss/sunxi-ss-core.c b/drivers/crypto/sunxi-ss/sunxi-ss-core.c
> new file mode 100644
> index 0000000..e66d7e2
> --- /dev/null
> +++ b/drivers/crypto/sunxi-ss/sunxi-ss-core.c
> @@ -0,0 +1,318 @@
> +/*
> + * sunxi-ss-core.c - hardware cryptographic accelerator for Allwinner A20 SoC
> + *
> + * Copyright (C) 2013-2014 Corentin LABBE <[email protected]>
> + *
> + * Core file which registers crypto algorithms supported by the SS.
> + *
> + * You could find a link for the datasheet in Documentation/arm/sunxi/README
> + *
> + * 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.
> + */
> +#include <linux/clk.h>
> +#include <linux/crypto.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <crypto/scatterwalk.h>
> +#include <linux/scatterlist.h>
> +#include <linux/interrupt.h>
> +#include <linux/delay.h>
> +
> +#include "sunxi-ss.h"
> +
> +struct sunxi_ss_ctx *ss;
> +
> +/*
> + * General notes for whole driver:
> + *
> + * After each request the device must be disabled with a write of 0 in SS_CTL
> + *
> + * For performance reason, we use writel_relaxed/read_relaxed for all
> + * operations on RX and TX FIFO and also SS_FCSR.
> + * Excepts for the last write on TX FIFO.
> + * For all other registers, we use writel/readl.
> + * See http://permalink.gmane.org/gmane.linux.ports.arm.kernel/117644
> + * and http://permalink.gmane.org/gmane.linux.ports.arm.kernel/117640
> + */

I don't really know why that comment is here, when there's not a
single writel in this file.

> +
> +static struct ahash_alg sunxi_md5_alg = {
> + .init = sunxi_hash_init,
> + .update = sunxi_hash_update,
> + .final = sunxi_hash_final,
> + .finup = sunxi_hash_finup,
> + .digest = sunxi_hash_digest,
> + .halg = {
> + .digestsize = MD5_DIGEST_SIZE,
> + .base = {
> + .cra_name = "md5",
> + .cra_driver_name = "md5-sunxi-ss",
> + .cra_priority = 300,
> + .cra_alignmask = 3,
> + .cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC,
> + .cra_blocksize = MD5_HMAC_BLOCK_SIZE,
> + .cra_ctxsize = sizeof(struct sunxi_req_ctx),
> + .cra_module = THIS_MODULE,
> + .cra_type = &crypto_ahash_type,
> + .cra_init = sunxi_hash_crainit
> + }
> + }
> +};
> +
> +static struct ahash_alg sunxi_sha1_alg = {
> + .init = sunxi_hash_init,
> + .update = sunxi_hash_update,
> + .final = sunxi_hash_final,
> + .finup = sunxi_hash_finup,
> + .digest = sunxi_hash_digest,
> + .halg = {
> + .digestsize = SHA1_DIGEST_SIZE,
> + .base = {
> + .cra_name = "sha1",
> + .cra_driver_name = "sha1-sunxi-ss",
> + .cra_priority = 300,
> + .cra_alignmask = 3,
> + .cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC,
> + .cra_blocksize = SHA1_BLOCK_SIZE,
> + .cra_ctxsize = sizeof(struct sunxi_req_ctx),
> + .cra_module = THIS_MODULE,
> + .cra_type = &crypto_ahash_type,
> + .cra_init = sunxi_hash_crainit
> + }
> + }
> +};
> +
> +static struct crypto_alg sunxi_cipher_algs[] = {
> +{
> + .cra_name = "cbc(aes)",
> + .cra_driver_name = "cbc-aes-sunxi-ss",
> + .cra_priority = 300,
> + .cra_blocksize = AES_BLOCK_SIZE,
> + .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER,
> + .cra_ctxsize = sizeof(struct sunxi_tfm_ctx),
> + .cra_module = THIS_MODULE,
> + .cra_alignmask = 3,
> + .cra_type = &crypto_ablkcipher_type,
> + .cra_init = sunxi_ss_cipher_init,
> + .cra_u = {
> + .ablkcipher = {
> + .min_keysize = AES_MIN_KEY_SIZE,
> + .max_keysize = AES_MAX_KEY_SIZE,
> + .ivsize = AES_BLOCK_SIZE,
> + .setkey = sunxi_ss_aes_setkey,
> + .encrypt = sunxi_ss_cipher_encrypt,
> + .decrypt = sunxi_ss_cipher_decrypt,
> + }
> + }
> +}, {
> + .cra_name = "cbc(des)",
> + .cra_driver_name = "cbc-des-sunxi-ss",
> + .cra_priority = 300,
> + .cra_blocksize = DES_BLOCK_SIZE,
> + .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER,
> + .cra_ctxsize = sizeof(struct sunxi_req_ctx),
> + .cra_module = THIS_MODULE,
> + .cra_alignmask = 3,
> + .cra_type = &crypto_ablkcipher_type,
> + .cra_init = sunxi_ss_cipher_init,
> + .cra_u.ablkcipher = {
> + .min_keysize = DES_KEY_SIZE,
> + .max_keysize = DES_KEY_SIZE,
> + .ivsize = DES_BLOCK_SIZE,
> + .setkey = sunxi_ss_des_setkey,
> + .encrypt = sunxi_ss_cipher_encrypt,
> + .decrypt = sunxi_ss_cipher_decrypt,
> + }
> +}, {
> + .cra_name = "cbc(des3_ede)",
> + .cra_driver_name = "cbc-des3-sunxi-ss",
> + .cra_priority = 300,
> + .cra_blocksize = DES3_EDE_BLOCK_SIZE,
> + .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER,
> + .cra_ctxsize = sizeof(struct sunxi_req_ctx),
> + .cra_module = THIS_MODULE,
> + .cra_alignmask = 3,
> + .cra_type = &crypto_ablkcipher_type,
> + .cra_init = sunxi_ss_cipher_init,
> + .cra_u.ablkcipher = {
> + .min_keysize = DES3_EDE_KEY_SIZE,
> + .max_keysize = DES3_EDE_KEY_SIZE,
> + .ivsize = DES3_EDE_BLOCK_SIZE,
> + .setkey = sunxi_ss_des3_setkey,
> + .encrypt = sunxi_ss_cipher_encrypt,
> + .decrypt = sunxi_ss_cipher_decrypt,
> + }
> +}
> +};
> +
> +static int sunxi_ss_probe(struct platform_device *pdev)
> +{
> + struct resource *res;
> + u32 v;
> + int err;
> + unsigned long cr;
> + const unsigned long cr_ahb = 24 * 1000 * 1000;
> + const unsigned long cr_mod = 150 * 1000 * 1000;
> +
> + if (!pdev->dev.of_node)
> + return -ENODEV;
> +
> + ss = devm_kzalloc(&pdev->dev, sizeof(*ss), GFP_KERNEL);
> + if (ss == NULL)
> + return -ENOMEM;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + ss->base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(ss->base)) {
> + dev_err(&pdev->dev, "Cannot request MMIO\n");
> + return PTR_ERR(ss->base);
> + }
> +
> + ss->ssclk = devm_clk_get(&pdev->dev, "mod");
> + if (IS_ERR(ss->ssclk)) {
> + err = PTR_ERR(ss->ssclk);
> + dev_err(&pdev->dev, "Cannot get SS clock err=%d\n", err);
> + return err;
> + }
> + dev_dbg(&pdev->dev, "clock ss acquired\n");
> +
> + ss->busclk = devm_clk_get(&pdev->dev, "ahb");
> + if (IS_ERR(ss->busclk)) {
> + err = PTR_ERR(ss->busclk);
> + dev_err(&pdev->dev, "Cannot get AHB SS clock err=%d\n", err);
> + return err;
> + }
> + dev_dbg(&pdev->dev, "clock ahb_ss acquired\n");
> +
> + /* Enable both clocks */
> + err = clk_prepare_enable(ss->busclk);
> + if (err != 0) {
> + dev_err(&pdev->dev, "Cannot prepare_enable busclk\n");
> + return err;
> + }
> + err = clk_prepare_enable(ss->ssclk);
> + if (err != 0) {
> + dev_err(&pdev->dev, "Cannot prepare_enable ssclk\n");
> + clk_disable_unprepare(ss->busclk);
> + return err;
> + }
> +
> + /*
> + * Check that clock have the correct rates gived in the datasheet
> + * Try to set the clock to the maximum allowed
> + */
> + err = clk_set_rate(ss->ssclk, cr_mod);
> + if (err != 0) {
> + dev_err(&pdev->dev, "Cannot set clock rate to ssclk\n");
> + clk_disable_unprepare(ss->ssclk);
> + clk_disable_unprepare(ss->busclk);
> + return err;
> + }
> +
> + cr = clk_get_rate(ss->busclk);
> + if (cr >= cr_ahb)
> + dev_dbg(&pdev->dev, "Clock bus %lu (%lu MHz) (must be >= %lu)\n",
> + cr, cr / 1000000, cr_ahb);
> + else
> + dev_warn(&pdev->dev, "Clock bus %lu (%lu MHz) (must be >= %lu)\n",
> + cr, cr / 1000000, cr_ahb);
> +
> + cr = clk_get_rate(ss->ssclk);
> + if (cr <= cr_mod)
> + if (cr < cr_mod)
> + dev_info(&pdev->dev, "Clock ss %lu (%lu MHz) (must be <= %lu)\n",
> + cr, cr / 1000000, cr_mod);
> + else
> + dev_dbg(&pdev->dev, "Clock ss %lu (%lu MHz) (must be <= %lu)\n",
> + cr, cr / 1000000, cr_mod);
> + else
> + dev_warn(&pdev->dev, "Clock ss is at %lu (%lu MHz) (must be <= %lu)\n",
> + cr, cr / 1000000, cr_mod);

If the set_rate fails, it will return an error. All this is useless.

> +
> + /*
> + * Datasheet named it "Die Bonding ID"
> + * I expect to be a sort of Security System Revision number.
> + * Since the A80 seems to have an other version of SS
> + * this info could be useful
> + */
> + writel(SS_ENABLED, ss->base + SS_CTL);
> + v = readl(ss->base + SS_CTL);
> + v >>= 16;
> + v &= 0x07;
> + dev_info(&pdev->dev, "Die ID %d\n", v);
> + writel(0, ss->base + SS_CTL);

If the A80 has a different IP, it will most likely have a different
compatible anyway. You can remove that code.

> +
> + ss->dev = &pdev->dev;
> +
> + mutex_init(&ss->lock);
> + mutex_init(&ss->bufin_lock);
> + mutex_init(&ss->bufout_lock);
> +
> + err = crypto_register_ahash(&sunxi_md5_alg);
> + if (err)
> + goto error_md5;
> + err = crypto_register_ahash(&sunxi_sha1_alg);
> + if (err)
> + goto error_sha1;
> + err = crypto_register_algs(sunxi_cipher_algs,
> + ARRAY_SIZE(sunxi_cipher_algs));
> + if (err)
> + goto error_ciphers;
> +
> + return 0;
> +error_ciphers:
> + crypto_unregister_ahash(&sunxi_sha1_alg);
> +error_sha1:
> + crypto_unregister_ahash(&sunxi_md5_alg);
> +error_md5:
> + clk_disable_unprepare(ss->ssclk);
> + clk_disable_unprepare(ss->busclk);
> + return err;
> +}
> +
> +static int __exit sunxi_ss_remove(struct platform_device *pdev)

The remove callback should not be in the __exit section.

Here, that function will get removed if the driver is compiled as
built-in the remove function will not even be in the kernel
image. Which will result in an instant crash when the kernel will try
to call this function (since it's not even there anymore).

> +{
> + if (!pdev->dev.of_node)
> + return 0;
> +
> + crypto_unregister_ahash(&sunxi_md5_alg);
> + crypto_unregister_ahash(&sunxi_sha1_alg);
> + crypto_unregister_algs(sunxi_cipher_algs,
> + ARRAY_SIZE(sunxi_cipher_algs));
> +
> + if (ss->buf_in != NULL)
> + kfree(ss->buf_in);
> + if (ss->buf_out != NULL)
> + kfree(ss->buf_out);
> +
> + writel(0, ss->base + SS_CTL);
> + clk_disable_unprepare(ss->busclk);
> + clk_disable_unprepare(ss->ssclk);
> + return 0;
> +}
> +
> +static const struct of_device_id a20ss_crypto_of_match_table[] = {
> + { .compatible = "allwinner,sun7i-a20-crypto" },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, a20ss_crypto_of_match_table);
> +
> +static struct platform_driver sunxi_ss_driver = {
> + .probe = sunxi_ss_probe,
> + .remove = __exit_p(sunxi_ss_remove),

And this is why you're not seeing any warning.

> + .driver = {
> + .owner = THIS_MODULE,

You can drop this, it's already set by module_platform_driver.

> + .name = "sunxi-ss",
> + .of_match_table = a20ss_crypto_of_match_table,
> + },
> +};
> +
> +module_platform_driver(sunxi_ss_driver);
> +
> +MODULE_DESCRIPTION("Allwinner Security System cryptographic accelerator");
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Corentin LABBE <[email protected]>");
> diff --git a/drivers/crypto/sunxi-ss/sunxi-ss-hash.c b/drivers/crypto/sunxi-ss/sunxi-ss-hash.c
> new file mode 100644
> index 0000000..ec8758f
> --- /dev/null
> +++ b/drivers/crypto/sunxi-ss/sunxi-ss-hash.c
> @@ -0,0 +1,445 @@
> +/*
> + * sunxi-ss-hash.c - hardware cryptographic accelerator for Allwinner A20 SoC
> + *
> + * Copyright (C) 2013-2014 Corentin LABBE <[email protected]>
> + *
> + * This file add support for MD5 and SHA1.
> + *
> + * You could find the datasheet in Documentation/arm/sunxi/README
> + *
> + * 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.
> + */
> +#include "sunxi-ss.h"
> +
> +/* This is a totaly arbitrary value */
> +#define SS_TIMEOUT 100
> +
> +extern struct sunxi_ss_ctx *ss;
> +
> +int sunxi_hash_crainit(struct crypto_tfm *tfm)
> +{
> + crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
> + sizeof(struct sunxi_req_ctx));
> + return 0;
> +}
> +
> +/* sunxi_hash_init: initialize request context */
> +int sunxi_hash_init(struct ahash_request *areq)
> +{
> + const char *hash_type;
> + struct sunxi_req_ctx *op = ahash_request_ctx(areq);
> +
> + memset(op, 0, sizeof(struct sunxi_req_ctx));
> +
> + hash_type = crypto_tfm_alg_name(areq->base.tfm);
> +
> + if (strcmp(hash_type, "sha1") == 0)
> + op->mode = SS_OP_SHA1;
> + if (strcmp(hash_type, "md5") == 0)
> + op->mode = SS_OP_MD5;
> + if (op->mode == 0)
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> +static u32 rx_cnt;
> +
> +inline void ss_writer(const u32 v)
> +{
> + u32 spaces;
> +
> + writel(v, ss->base + SS_RXFIFO);
> + rx_cnt--;
> + while (rx_cnt == 0) {
> + spaces = readl_relaxed(ss->base + SS_FCSR);
> + rx_cnt = SS_RXFIFO_SPACES(spaces);
> + }
> +}

Errrr. What?!

Who sets that rx_cnt variable? And it persists between calls? It looks
broken.

> +inline void ss_writer_relaxed(const u32 v)
> +{
> + u32 spaces;
> +
> + writel_relaxed(v, ss->base + SS_RXFIFO);
> + rx_cnt--;
> + while (rx_cnt == 0) {
> + spaces = readl_relaxed(ss->base + SS_FCSR);
> + rx_cnt = SS_RXFIFO_SPACES(spaces);
> + }
> +}
> +
> +/*
> + * sunxi_hash_update: update hash engine
> + *
> + * Could be used for both SHA1 and MD5
> + * Write data by step of 32bits and put then in the SS.
> + *
> + * Since we cannot leave partial data and hash state in the engine,
> + * we need to get the hash state at the end of this function.
> + * After some work, I have found that we can get the hash state every 64o
> + *
> + * So the first work is to get the number of bytes to write to SS modulo 64
> + * The extra bytes will go to two different destination:
> + * op->wait for full 32bits word
> + * op->wb (waiting bytes) for partial 32 bits word
> + * So we can have up to (64/4)-1 op->wait words and 0/1/2/3 bytes in wb
> + *
> + * So at the begin of update()
> + * if op->nwait * 4 + areq->nbytes < 64
> + * => all data writed to wait buffers and end=0
> + * if not write all nwait to the device and position end to complete to 64o
> + *
> + * example 1:
> + * update1 60o => nwait=15
> + * update2 60o => need one more word to have 64o
> + * end=4
> + * so write all data in op->wait and one word of SGs
> + * write remaining data in op->wait
> + * final state op->nwait=14
> + */
> +int sunxi_hash_update(struct ahash_request *areq)
> +{
> + u32 v, ivmode = 0;
> + unsigned int i = 0;
> + /*
> + * i is the total bytes read from SGs, to be compared to areq->nbytes
> + * i is important because we cannot rely on SG length since the sum of
> + * SG->length could be greater than areq->nbytes
> + */
> +
> + struct sunxi_req_ctx *op = ahash_request_ctx(areq);
> + struct scatterlist *in_sg;
> + unsigned int in_i = 0; /* advancement in the current SG */
> + u64 end;
> + /*
> + * end is the position when we need to stop writing to the device,
> + * to be compared to i
> + */
> + int in_r;
> + void *src_addr;
> +
> + dev_dbg(ss->dev, "%s %s bc=%llu len=%u mode=%x bw=%u ww=%u",
> + __func__, crypto_tfm_alg_name(areq->base.tfm),
> + op->byte_count, areq->nbytes, op->mode,
> + op->nbw, op->nwait);
> +
> + if (areq->nbytes == 0)
> + return 0;
> +
> + end = ((areq->nbytes + op->nwait * 4 + op->nbw) / 64) * 64
> + - op->nbw - op->nwait * 4;
> +
> + if (end > areq->nbytes || areq->nbytes - end > 63) {
> + dev_err(ss->dev, "ERROR: Bound error %llu %u\n",
> + end, areq->nbytes);
> + return -EINVAL;
> + }
> +
> + if (op->nwait > 0 && end > 0) {
> + /* a precedent update was done */
> + for (i = 0; i < op->nwait; i++) {
> + ss_writer(op->wait[i]);
> + op->byte_count += 4;
> + }
> + op->nwait = 0;
> + }
> +
> + mutex_lock(&ss->lock);
> + /*
> + * if some data have been processed before,
> + * we need to restore the partial hash state
> + */
> + if (op->byte_count > 0) {
> + ivmode = SS_IV_ARBITRARY;
> + for (i = 0; i < 5; i++)
> + writel(op->hash[i], ss->base + SS_IV0 + i * 4);
> + }
> + /* Enable the device */
> + writel(op->mode | SS_ENABLED | ivmode, ss->base + SS_CTL);
> +
> + rx_cnt = 0;
> + i = 0;
> +
> + in_sg = areq->src;
> + src_addr = kmap(sg_page(in_sg)) + in_sg->offset;
> + if (src_addr == NULL) {
> + mutex_unlock(&ss->lock);
> + dev_err(ss->dev, "ERROR: Cannot kmap source buffer\n");
> + return -EFAULT;
> + }
> + do {
> + /*
> + * step 1, if some bytes remains from last SG,
> + * try to complete them to 4 and send that word
> + */
> + if (op->nbw > 0) {
> + while (op->nbw < 4 && i < areq->nbytes &&
> + in_i < in_sg->length) {
> + op->wb |= (*(u8 *)(src_addr + in_i))
> + << (8 * op->nbw);
> + dev_dbg(ss->dev, "%s Complete w=%d wb=%x\n",
> + __func__, op->nbw, op->wb);
> + i++;
> + in_i++;
> + op->nbw++;
> + }
> + if (op->nbw == 4) {
> + if (i <= end) {
> + ss_writer(op->wb);
> + op->byte_count += 4;
> + } else {
> + op->wait[op->nwait] = op->wb;
> + op->nwait++;
> + dev_dbg(ss->dev, "%s Keep %u bytes after %llu\n",
> + __func__, op->nwait, end);
> + }
> + op->nbw = 0;
> + op->wb = 0;
> + }
> + }
> + /* step 2, main loop, read data 4bytes at a time */
> + while (i < areq->nbytes && in_i < in_sg->length) {
> + /* how many bytes we can read, (we need 4) */
> + in_r = min(in_sg->length - in_i, areq->nbytes - i);
> + if (in_r < 4) {
> + /* Not enough data to write to the device */
> + op->wb = 0;
> + while (in_r > 0) {
> + op->wb |= (*(u8 *)(src_addr + in_i))
> + << (8 * op->nbw);
> + dev_dbg(ss->dev, "%s ending bw=%d wb=%x\n",
> + __func__, op->nbw, op->wb);
> + in_r--;
> + i++;
> + in_i++;
> + op->nbw++;
> + }
> + goto nextsg;
> + }
> + v = *(u32 *)(src_addr + in_i);
> + if (i < end) {
> + /* last write must be done without relaxed */
> + if (i + 4 >= end)
> + ss_writer(v);
> + else
> + ss_writer_relaxed(v);
> + i += 4;
> + op->byte_count += 4;
> + in_i += 4;
> + } else {
> + op->wait[op->nwait] = v;
> + i += 4;
> + in_i += 4;
> + op->nwait++;
> + dev_dbg(ss->dev, "%s Keep word ww=%u after %llu\n",
> + __func__, op->nwait, end);
> + if (op->nwait > 15) {
> + dev_err(ss->dev, "FATAL: Cannot enqueue more, bug?\n");
> + writel(0, ss->base + SS_CTL);
> + mutex_unlock(&ss->lock);
> + return -EIO;
> + }
> + }
> + }
> +nextsg:
> + /* Nothing more to read in this SG */
> + if (in_i == in_sg->length) {
> + kunmap(sg_page(in_sg));
> + do {
> + in_sg = sg_next(in_sg);
> + } while (in_sg != NULL && in_sg->length == 0);
> + in_i = 0;
> + if (in_sg != NULL) {
> + src_addr = kmap(sg_page(in_sg)) + in_sg->offset;
> + if (src_addr == NULL) {
> + mutex_unlock(&ss->lock);
> + dev_err(ss->dev, "ERROR: Cannot kmap source buffer\n");
> + return -EFAULT;
> + }
> + }
> + }
> + } while (in_sg != NULL && i < areq->nbytes);
> +
> + /* ask the device to finish the hashing */
> + writel(op->mode | SS_ENABLED | SS_DATA_END, ss->base + SS_CTL);
> + i = 0;
> + do {
> + v = readl(ss->base + SS_CTL);
> + i++;
> + } while (i < SS_TIMEOUT && (v & SS_DATA_END) > 0);
> + if (i >= SS_TIMEOUT) {
> + dev_err(ss->dev, "ERROR: %s hash end timeout after %d loop, CTL=%x\n",
> + __func__, i, v);
> + writel(0, ss->base + SS_CTL);
> + mutex_unlock(&ss->lock);
> + return -EIO;
> + }
> +
> + /* get the partial hash */
> + if (op->mode == SS_OP_SHA1) {
> + for (i = 0; i < 5; i++)
> + op->hash[i] = readl(ss->base + SS_MD0 + i * 4);
> + } else {
> + for (i = 0; i < 4; i++)
> + op->hash[i] = readl(ss->base + SS_MD0 + i * 4);
> + }
> +
> + writel(0, ss->base + SS_CTL);
> + mutex_unlock(&ss->lock);
> + return 0;
> +}
> +
> +/*
> + * sunxi_hash_final: finalize hashing operation
> + *
> + * If we have some remaining bytes, we write them.
> + * Then ask the SS for finalizing the hashing operation
> + */
> +int sunxi_hash_final(struct ahash_request *areq)
> +{
> + u32 v, ivmode = 0;
> + unsigned int i;
> + int zeros;
> + unsigned int index, padlen;
> + __be64 bits;
> + struct sunxi_req_ctx *op = ahash_request_ctx(areq);
> +
> + dev_dbg(ss->dev, "%s byte=%llu len=%u mode=%x bw=%u %x h=%x ww=%u",
> + __func__, op->byte_count, areq->nbytes, op->mode,
> + op->nbw, op->wb, op->hash[0], op->nwait);
> +
> + mutex_lock(&ss->lock);
> + rx_cnt = 0;
> +
> + /*
> + * if we have already writed something,
> + * restore the partial hash state
> + */
> + if (op->byte_count > 0) {
> + ivmode = SS_IV_ARBITRARY;
> + for (i = 0; i < 5; i++)
> + writel(op->hash[i], ss->base + SS_IV0 + i * 4);
> + }
> + writel(op->mode | SS_ENABLED | ivmode, ss->base + SS_CTL);
> +
> + /* write the remaining words of the wait buffer */
> + if (op->nwait > 0) {
> + for (i = 0; i < op->nwait; i++) {
> + v = op->wait[i];
> + ss_writer(v);
> + op->byte_count += 4;
> + dev_dbg(ss->dev, "%s write %llu i=%u %x\n",
> + __func__, op->byte_count, i, v);
> + }
> + op->nwait = 0;
> + }
> +
> + /* write the remaining bytes of the nbw buffer */
> + if (op->nbw > 0) {
> + op->wb |= ((1 << 7) << (op->nbw * 8));
> + ss_writer(op->wb);
> + } else {
> + ss_writer((1 << 7));
> + }
> +
> + /*
> + * number of space to pad to obtain 64o minus 8(size) minus 4 (final 1)
> + * I take the operations from other md5/sha1 implementations
> + */
> +
> + /* we have already send 4 more byte of which nbw data */
> + if (op->mode == SS_OP_MD5) {
> + index = (op->byte_count + 4) & 0x3f;
> + op->byte_count += op->nbw;
> + if (index > 56)
> + zeros = (120 - index) / 4;
> + else
> + zeros = (56 - index) / 4;
> + } else {
> + op->byte_count += op->nbw;
> + index = op->byte_count & 0x3f;
> + padlen = (index < 56) ? (56 - index) : ((64+56) - index);
> + zeros = (padlen - 1) / 4;
> + }
> + for (i = 0; i < zeros; i++)
> + ss_writer(0);
> +
> + /* write the length of data */
> + if (op->mode == SS_OP_SHA1) {
> + bits = cpu_to_be64(op->byte_count << 3);
> + ss_writer(bits & 0xffffffff);
> + ss_writer((bits >> 32) & 0xffffffff);
> + } else {
> + ss_writer((op->byte_count << 3) & 0xffffffff);
> + ss_writer((op->byte_count >> 29) & 0xffffffff);
> + }
> +
> + /* Tell the SS to stop the hashing */
> + writel(op->mode | SS_ENABLED | SS_DATA_END, ss->base + SS_CTL);
> +
> + /*
> + * Wait for SS to finish the hash.
> + * The timeout could happend only in case of bad overcloking
> + * or driver bug.
> + */
> + i = 0;
> + do {
> + v = readl(ss->base + SS_CTL);
> + i++;
> + } while (i < SS_TIMEOUT && (v & SS_DATA_END) > 0);
> + if (i >= SS_TIMEOUT) {
> + dev_err(ss->dev, "ERROR: hash end timeout %d>%d ctl=%x len=%u\n",
> + i, SS_TIMEOUT, v, areq->nbytes);
> + writel(0, ss->base + SS_CTL);
> + mutex_unlock(&ss->lock);
> + return -EIO;
> + }
> +
> + /* Get the hash from the device */
> + if (op->mode == SS_OP_SHA1) {
> + for (i = 0; i < 5; i++) {
> + v = cpu_to_be32(readl(ss->base + SS_MD0 + i * 4));
> + memcpy(areq->result + i * 4, &v, 4);
> + }
> + } else {
> + for (i = 0; i < 4; i++) {
> + v = readl(ss->base + SS_MD0 + i * 4);
> + memcpy(areq->result + i * 4, &v, 4);
> + }
> + }
> + writel(0, ss->base + SS_CTL);
> + mutex_unlock(&ss->lock);
> + return 0;
> +}
> +
> +/* sunxi_hash_finup: finalize hashing operation after an update */
> +int sunxi_hash_finup(struct ahash_request *areq)
> +{
> + int err;
> +
> + err = sunxi_hash_update(areq);
> + if (err != 0)
> + return err;
> +
> + return sunxi_hash_final(areq);
> +}
> +
> +/* combo of init/update/final functions */
> +int sunxi_hash_digest(struct ahash_request *areq)
> +{
> + int err;
> +
> + err = sunxi_hash_init(areq);
> + if (err != 0)
> + return err;
> +
> + err = sunxi_hash_update(areq);
> + if (err != 0)
> + return err;
> +
> + return sunxi_hash_final(areq);
> +}
> diff --git a/drivers/crypto/sunxi-ss/sunxi-ss.h b/drivers/crypto/sunxi-ss/sunxi-ss.h
> new file mode 100644
> index 0000000..331e75b
> --- /dev/null
> +++ b/drivers/crypto/sunxi-ss/sunxi-ss.h
> @@ -0,0 +1,193 @@
> +/*
> + * sunxi-ss.c - hardware cryptographic accelerator for Allwinner A20 SoC
> + *
> + * Copyright (C) 2013-2014 Corentin LABBE <[email protected]>
> + *
> + * Support AES cipher with 128,192,256 bits keysize.
> + * Support MD5 and SHA1 hash algorithms.
> + * Support DES and 3DES
> + *
> + * You could find the datasheet in Documentation/arm/sunxi/README
> + *
> + * Licensed under the GPL-2.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/crypto.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <crypto/scatterwalk.h>
> +#include <linux/scatterlist.h>
> +#include <linux/interrupt.h>
> +#include <linux/delay.h>
> +#include <crypto/md5.h>
> +#include <crypto/sha.h>
> +#include <crypto/hash.h>
> +#include <crypto/internal/hash.h>
> +#include <crypto/aes.h>
> +#include <crypto/des.h>
> +#include <crypto/internal/rng.h>
> +
> +#define SS_CTL 0x00
> +#define SS_KEY0 0x04
> +#define SS_KEY1 0x08
> +#define SS_KEY2 0x0C
> +#define SS_KEY3 0x10
> +#define SS_KEY4 0x14
> +#define SS_KEY5 0x18
> +#define SS_KEY6 0x1C
> +#define SS_KEY7 0x20
> +
> +#define SS_IV0 0x24
> +#define SS_IV1 0x28
> +#define SS_IV2 0x2C
> +#define SS_IV3 0x30
> +
> +#define SS_CNT0 0x34
> +#define SS_CNT1 0x38
> +#define SS_CNT2 0x3C
> +#define SS_CNT3 0x40
> +
> +#define SS_FCSR 0x44
> +#define SS_ICSR 0x48
> +
> +#define SS_MD0 0x4C
> +#define SS_MD1 0x50
> +#define SS_MD2 0x54
> +#define SS_MD3 0x58
> +#define SS_MD4 0x5C
> +
> +#define SS_RXFIFO 0x200
> +#define SS_TXFIFO 0x204
> +
> +/* SS_CTL configuration values */
> +
> +/* PRNG generator mode - bit 15 */
> +#define SS_PRNG_ONESHOT (0 << 15)
> +#define SS_PRNG_CONTINUE (1 << 15)
> +
> +/* IV mode for hash */
> +#define SS_IV_ARBITRARY (1 << 14)
> +
> +/* SS operation mode - bits 12-13 */
> +#define SS_ECB (0 << 12)
> +#define SS_CBC (1 << 12)
> +#define SS_CNT (2 << 12)
> +
> +/* Counter width for CNT mode - bits 10-11 */
> +#define SS_CNT_16BITS (0 << 10)
> +#define SS_CNT_32BITS (1 << 10)
> +#define SS_CNT_64BITS (2 << 10)
> +
> +/* Key size for AES - bits 8-9 */
> +#define SS_AES_128BITS (0 << 8)
> +#define SS_AES_192BITS (1 << 8)
> +#define SS_AES_256BITS (2 << 8)
> +
> +/* Operation direction - bit 7 */
> +#define SS_ENCRYPTION (0 << 7)
> +#define SS_DECRYPTION (1 << 7)
> +
> +/* SS Method - bits 4-6 */
> +#define SS_OP_AES (0 << 4)
> +#define SS_OP_DES (1 << 4)
> +#define SS_OP_3DES (2 << 4)
> +#define SS_OP_SHA1 (3 << 4)
> +#define SS_OP_MD5 (4 << 4)
> +#define SS_OP_PRNG (5 << 4)
> +
> +/* Data end bit - bit 2 */
> +#define SS_DATA_END (1 << 2)
> +
> +/* PRNG start bit - bit 1 */
> +#define SS_PRNG_START (1 << 1)
> +
> +/* SS Enable bit - bit 0 */
> +#define SS_DISABLED (0 << 0)
> +#define SS_ENABLED (1 << 0)
> +
> +/* SS_FCSR configuration values */
> +/* RX FIFO status - bit 30 */
> +#define SS_RXFIFO_FREE (1 << 30)
> +
> +/* RX FIFO empty spaces - bits 24-29 */
> +#define SS_RXFIFO_SPACES(val) (((val) >> 24) & 0x3f)
> +
> +/* TX FIFO status - bit 22 */
> +#define SS_TXFIFO_AVAILABLE (1 << 22)
> +
> +/* TX FIFO available spaces - bits 16-21 */
> +#define SS_TXFIFO_SPACES(val) (((val) >> 16) & 0x3f)
> +
> +#define SS_RXFIFO_EMP_INT_PENDING (1 << 10)
> +#define SS_TXFIFO_AVA_INT_PENDING (1 << 8)
> +#define SS_RXFIFO_EMP_INT_ENABLE (1 << 2)
> +#define SS_TXFIFO_AVA_INT_ENABLE (1 << 0)
> +
> +/* SS_ICSR configuration values */
> +#define SS_ICS_DRQ_ENABLE (1 << 4)
> +
> +struct sunxi_ss_ctx {
> + void __iomem *base;
> + int irq;
> + struct clk *busclk;
> + struct clk *ssclk;
> + struct device *dev;
> + struct resource *res;
> + void *buf_in; /* pointer to data to be uploaded to the device */
> + size_t buf_in_size; /* size of buf_in */
> + void *buf_out;
> + size_t buf_out_size;
> + struct mutex lock; /* control the use of the device */
> + struct mutex bufout_lock; /* control the use of buf_out*/
> + struct mutex bufin_lock; /* control the sue of buf_in*/
> +};
> +
> +struct sunxi_tfm_ctx {
> + u32 key[AES_MAX_KEY_SIZE / 4];/* divided by sizeof(u32) */
> + u32 keylen;
> + u32 keymode;
> +};
> +
> +struct sunxi_req_ctx {
> + u32 mode;
> + u64 byte_count; /* number of bytes "uploaded" to the device */
> + u32 wb; /* a partial word waiting to be completed and
> + uploaded to the device */
> + /* number of bytes to be uploaded in the wb word */
> + unsigned int nbw;
> + u32 hash[5];
> + u32 wait[64];
> + unsigned int nwait;
> +};
> +
> +#define SS_SEED_LEN (192/8)
> +#define SS_DATA_LEN (160/8)
> +
> +struct prng_context {
> + u32 seed[SS_SEED_LEN/4];
> + unsigned int slen;
> +};
> +
> +int sunxi_hash_crainit(struct crypto_tfm *tfm);
> +int sunxi_hash_init(struct ahash_request *areq);
> +int sunxi_hash_update(struct ahash_request *areq);
> +int sunxi_hash_final(struct ahash_request *areq);
> +int sunxi_hash_finup(struct ahash_request *areq);
> +int sunxi_hash_digest(struct ahash_request *areq);
> +int sunxi_hash_export(struct ahash_request *areq, void *out);
> +int sunxi_hash_import(struct ahash_request *areq, const void *in);
> +
> +int sunxi_ss_aes_poll(struct ablkcipher_request *areq, u32 mode);
> +int sunxi_ss_des_poll(struct ablkcipher_request *areq, u32 mode);
> +int sunxi_ss_cipher_init(struct crypto_tfm *tfm);
> +int sunxi_ss_cipher_encrypt(struct ablkcipher_request *areq);
> +int sunxi_ss_cipher_decrypt(struct ablkcipher_request *areq);
> +int sunxi_ss_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
> + unsigned int keylen);
> +int sunxi_ss_des_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
> + unsigned int keylen);
> +int sunxi_ss_des3_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
> + unsigned int keylen);
> --
> 2.0.4
>

Thanks,
Maxime

--
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

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2014-10-22 09:02:00

by Arnd Bergmann

[permalink] [raw]

Subject: Re: [PATCH v5 4/4] crypto: Add Allwinner Security System crypto accelerator

by Herbert Xu

[permalink] [raw]

Subject: Re: [PATCH v5 4/4] crypto: Add Allwinner Security System crypto accelerator

On Sun, Oct 19, 2014 at 04:16:22PM +0200, LABBE Corentin wrote:
> Add support for the Security System included in Allwinner SoC A20.
> The Security System is a hardware cryptographic accelerator that support AES/MD5/SHA1/DES/3DES/PRNG algorithms.
>
> Signed-off-by: LABBE Corentin <[email protected]>

OK this is much better. However it seems that export/import
is still missing?

> + src_addr = kmap_atomic(sg_page(in_sg)) + in_sg->offset;
> + if (src_addr == NULL) {
> + dev_err(ss->dev, "kmap_atomic error for src SG\n");
> + writel(0, ss->base + SS_CTL);
> + mutex_unlock(&ss->lock);

I overlooked this the last time around. You cannot use mutexes
here as you can be called from softirq context so you need spin
locks.

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

2014-11-06 14:30:10

On Thu, Nov 06, 2014 at 10:32:18PM +0800, Herbert Xu wrote:
> On Thu, Nov 06, 2014 at 03:26:33PM +0100, Maxime Ripard wrote:
> >
> > But you still haven't explain why the driver, while it doesn't handle
> > the user space buffer at any time, should be worried that the data the
> > framework has given him are actually mapped.
>
> Encryption is used by IPsec and SKBs can be allocated in highmem.
> algif also exposes all ciphers to user-space memory which can also
> be in highmem.

Ok. We keep going in circles here.

I know that algif handles userspace memory that can be in
highmem. What I don't get, is that just like a *driver* doesn't have
to call copy_from_user, why would it need to call kmap...

That's something that should be in the framework itself, not the
driver. And the argument that most drivers use DMA seems like a broken
assumption.

But hey, you're the one that will maintain this mess, so I guess you
have the final word.

Maxime

--
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

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