Re: [PATCH 3/5] crypto: tegra: Add Tegra Security Engine driver

[Krzysztof Kozlowski]

On 13/12/2023 13:20, Akhil R wrote:
> Add support for Tegra Security Engine which can accelerates various
> crypto algorithms. The Engine has two separate instances within for
> AES and HASH algorithms respectively.
> 
> The driver registers two crypto engines - one for AES and another for
> HASH algorithms and these operate independently and both uses the host1x
> bus. Additionally, it provides  hardware-assisted key protection for up
> to 15 symmetric keys which it can use for the cipher operations.
> 
> Signed-off-by: Akhil R <akhilrajeev@xxxxxxxxxx>
> ---

...

> +
> +int tegra_init_hash(struct tegra_se *se)
> +{
> +	struct ahash_engine_alg *alg;
> +	int i, ret;
> +
> +	se->manifest = tegra_hash_kac_manifest;
> +
> +	for (i = 0; i < ARRAY_SIZE(tegra_hash_algs); i++) {
> +		tegra_hash_algs[i].se_dev = se;
> +		alg = &tegra_hash_algs[i].alg.ahash;
> +
> +		ret = crypto_engine_register_ahash(alg);
> +		if (ret) {
> +			dev_err(se->dev, "failed to register %s\n",
> +				alg->base.halg.base.cra_name);
> +			goto sha_err;
> +		}
> +	}
> +
> +	dev_info(se->dev, "registered HASH algorithms\n");

Drop, not needed. Actually drop simple success messages. Drivers do not
spam dmesg without need.

...

> +
> +int tegra_se_host1x_register(struct tegra_se *se)
> +{
> +	INIT_LIST_HEAD(&se->client.list);
> +	se->client.dev = se->dev;
> +	se->client.ops = &tegra_se_client_ops;
> +	se->client.class = se->hw->host1x_class;
> +	se->client.num_syncpts = 1;
> +
> +	host1x_client_register(&se->client);
> +
> +	return 0;
> +}
> +
> +static int tegra_se_clk_init(struct tegra_se *se)
> +{
> +	int i, ret;
> +
> +	se->clk = devm_clk_get(se->dev, NULL);
> +	if (IS_ERR(se->clk)) {
> +		dev_err(se->dev, "failed to get clock\n");

Why do you print failures multiple times? Once here, second in probe.

return dev_err_probe

> +		return PTR_ERR(se->clk);
> +	}
> +
> +	ret = clk_set_rate(se->clk, ULONG_MAX);
> +	if (ret) {
> +		dev_err(se->dev, "failed to set %d clock rate", i);

Same comments

> +		return ret;
> +	}
> +
> +	ret = clk_prepare_enable(se->clk);
> +	if (ret) {
> +		dev_err(se->dev, "failed to enable clocks\n");

Same comments

> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static void tegra_se_clk_deinit(struct tegra_se *se)
> +{
> +	clk_disable_unprepare(se->clk);

Why aren't you using devm_clk_get_enabled? This looks like porting some
old, out-of-tree vendor crappy driver :(

> +}
> +
> +static int tegra_se_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct tegra_se *se;
> +	int ret;
> +
> +	se = devm_kzalloc(dev, sizeof(*se), GFP_KERNEL);
> +	if (!se)
> +		return -ENOMEM;
> +
> +	se->dev = dev;
> +	se->owner = TEGRA_GPSE_ID;
> +	se->hw = device_get_match_data(&pdev->dev);
> +
> +	se->base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(se->base))
> +		return PTR_ERR(se->base);
> +
> +	dma_set_mask_and_coherent(dev, DMA_BIT_MASK(39));
> +	platform_set_drvdata(pdev, se);
> +
> +	ret = tegra_se_clk_init(se);
> +	if (ret) {
> +		dev_err(dev, "failed to init clocks\n");

Syntax is:
return dev_err_probe

> +		return ret;
> +	}
> +
> +	if (!tegra_dev_iommu_get_stream_id(dev, &se->stream_id)) {
> +		dev_err(dev, "failed to get IOMMU stream ID\n");

dev_err_probe

> +		goto clk_deinit;
> +	}
> +
> +	se_writel(se, se->stream_id, SE_STREAM_ID);
> +
> +	se->engine = crypto_engine_alloc_init(dev, 0);
> +	if (!se->engine) {
> +		dev_err(dev, "failed to init crypto engine\n");

Really? Test your code with coccinelle. Drop.

> +		ret = -ENOMEM;
> +		goto iommu_free;
> +	}
> +
> +	ret = crypto_engine_start(se->engine);
> +	if (ret) {
> +		dev_err(dev, "failed to start crypto engine\n");

dev_err_probe

> +		goto engine_exit;
> +	}
> +
> +	ret = tegra_se_host1x_register(se);
> +	if (ret) {
> +		dev_err(dev, "failed to init host1x params\n");

dev_err_probe

> +		goto engine_stop;
> +	}
> +
> +	return 0;
> +
> +engine_stop:
> +	crypto_engine_stop(se->engine);
> +engine_exit:
> +	crypto_engine_exit(se->engine);
> +iommu_free:
> +	iommu_fwspec_free(se->dev);
> +clk_deinit:
> +	tegra_se_clk_deinit(se);
> +
> +	return ret;
> +}
> +
> +static int tegra_se_remove(struct platform_device *pdev)
> +{
> +	struct tegra_se *se = platform_get_drvdata(pdev);
> +
> +	crypto_engine_stop(se->engine);
> +	crypto_engine_exit(se->engine);
> +	iommu_fwspec_free(se->dev);
> +	host1x_client_unregister(&se->client);
> +	tegra_se_clk_deinit(se);
> +
> +	return 0;
> +}
> +
> +static const struct tegra_se_regs tegra234_aes1_regs = {
> +	.config = SE_AES1_CFG,
> +	.op = SE_AES1_OPERATION,
> +	.last_blk = SE_AES1_LAST_BLOCK,
> +	.linear_ctr = SE_AES1_LINEAR_CTR,
> +	.aad_len = SE_AES1_AAD_LEN,
> +	.cryp_msg_len = SE_AES1_CRYPTO_MSG_LEN,
> +	.manifest = SE_AES1_KEYMANIFEST,
> +	.key_addr = SE_AES1_KEY_ADDR,
> +	.key_data = SE_AES1_KEY_DATA,
> +	.key_dst = SE_AES1_KEY_DST,
> +	.result = SE_AES1_CMAC_RESULT,
> +};
> +
> +static const struct tegra_se_regs tegra234_hash_regs = {
> +	.config = SE_SHA_CFG,
> +	.op = SE_SHA_OPERATION,
> +	.manifest = SE_SHA_KEYMANIFEST,
> +	.key_addr = SE_SHA_KEY_ADDR,
> +	.key_data = SE_SHA_KEY_DATA,
> +	.key_dst = SE_SHA_KEY_DST,
> +	.result = SE_SHA_HASH_RESULT,
> +};
> +
> +static const struct tegra_se_hw tegra234_aes_hw = {
> +	.regs = &tegra234_aes1_regs,
> +	.kac_ver = 1,
> +	.host1x_class = 0x3b,
> +	.init_alg = tegra_init_aes,
> +	.deinit_alg = tegra_deinit_aes,
> +};
> +
> +static const struct tegra_se_hw tegra234_hash_hw = {
> +	.regs = &tegra234_hash_regs,
> +	.kac_ver = 1,
> +	.host1x_class = 0x3d,
> +	.init_alg = tegra_init_hash,
> +	.deinit_alg = tegra_deinit_hash,
> +};
> +
> +static const struct of_device_id tegra_se_of_match[] = {
> +	{
> +		.compatible = "nvidia,tegra234-se2-aes",
> +		.data = &tegra234_aes_hw
> +	}, {
> +		.compatible = "nvidia,tegra234-se4-hash",
> +		.data = &tegra234_hash_hw,
> +	},
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, tegra_se_of_match);
> +
> +static struct platform_driver tegra_se_driver = {
> +	.driver = {
> +		.name	= "tegra-se",
> +		.of_match_table = tegra_se_of_match,
> +	},
> +	.probe		= tegra_se_probe,
> +	.remove		= tegra_se_remove,
> +};
> +
> +static int tegra_se_host1x_probe(struct host1x_device *dev)
> +{
> +	return host1x_device_init(dev);
> +}
> +
> +static int tegra_se_host1x_remove(struct host1x_device *dev)
> +{
> +	host1x_device_exit(dev);
> +
> +	return 0;
> +}
> +


...

> +		return -EINVAL;
> +}
> +
> +/* Functions */
> +int tegra_init_aead(struct tegra_se *se);

I look for it and cannot find it... Drop.

> +int tegra_init_aes(struct tegra_se *se);
> +int tegra_init_hash(struct tegra_se *se);
> +void tegra_deinit_aes(struct tegra_se *se);
> +void tegra_deinit_hash(struct tegra_se *se);
> +
> +int tegra_key_submit(struct tegra_se *se, const u8 *key, u32 keylen, u32 alg, u32 *keyid);
> +unsigned int tegra_key_get_idx(struct tegra_se *se, u32 keyid);
> +void tegra_key_invalidate(struct tegra_se *se, u32 keyid, u32 alg);
> +
> +int tegra_se_host1x_register(struct tegra_se *se);
> +int tegra_se_host1x_submit(struct tegra_se *se, u32 size);

Everything looks bogus...

> +
> +static inline void se_writel(struct tegra_se *se, u32 val,
> +			     unsigned int offset)
> +{
> +	writel_relaxed(val, se->base + offset);
> +}
> +
> +static inline u32 se_readl(struct tegra_se *se, unsigned int offset)
> +{
> +	return readl_relaxed(se->base + offset);
> +}

Both wrappers are useless.

> +
> +/****
> + *

Use Linux coding style comments.

> + * HOST1x OPCODES
> + *
> + ****/
> +

...

> +
> +static inline u32 host1x_opcode_nonincr(unsigned int offset, unsigned int count)
> +{
> +	return (2 << 28) | (offset << 16) | count;
> +}
> +
> +static inline u32 host1x_uclass_incr_syncpt_cond_f(u32 v)
> +{
> +		return (v & 0xff) << 10;

Fix indentation, in other places as well.


Best regards,
Krzysztof