Re: [PATCH v2 15/18] crypto: rockchip: introduce PM

John Keeping
2022-03-03T12:57:24Z

On Wed, Mar 02, 2022 at 09:11:10PM +0000, Corentin Labbe wrote:
> Add runtime PM support for rockchip crypto.
>
> Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
> ---
> drivers/crypto/Kconfig | 1 +
> drivers/crypto/rockchip/rk3288_crypto.c | 50 ++++++++++++++++++-
> drivers/crypto/rockchip/rk3288_crypto.h | 1 +
> drivers/crypto/rockchip/rk3288_crypto_ahash.c | 11 ++++
> .../crypto/rockchip/rk3288_crypto_skcipher.c | 10 ++++
> 5 files changed, 71 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
> index 04c8e332c5a1..685631a5cbea 100644
> --- a/drivers/crypto/Kconfig
> +++ b/drivers/crypto/Kconfig
> @@ -784,6 +784,7 @@ config CRYPTO_DEV_IMGTEC_HASH
> config CRYPTO_DEV_ROCKCHIP
> tristate "Rockchip's Cryptographic Engine driver"
> depends on OF && ARCH_ROCKCHIP
> + depends on PM

Does this need to depend on PM? If you enable the clock in _probe then
use pm_runtime_put_autosuspend() the no-op helpers when !PM will mean
this works whether PM is enabled or not.

> select CRYPTO_AES
> select CRYPTO_ENGINE
> select CRYPTO_LIB_DES
> diff --git a/drivers/crypto/rockchip/rk3288_crypto.c b/drivers/crypto/rockchip/rk3288_crypto.c
> index cd0755731cf7..ba56f8ff97c3 100644
> --- a/drivers/crypto/rockchip/rk3288_crypto.c
> +++ b/drivers/crypto/rockchip/rk3288_crypto.c
> @@ -57,6 +57,48 @@ static void rk_crypto_disable_clk(struct rk_crypto_info *dev)
> clk_disable_unprepare(dev->sclk);
> }
>
> +/*
> + * Power management strategy: The device is suspended unless a TFM exists for
> + * one of the algorithms proposed by this driver.
> + */
> +static int rk_crypto_pm_suspend(struct device *dev)
> +{
> + struct rk_crypto_info *rkdev = dev_get_drvdata(dev);
> +
> + rk_crypto_disable_clk(rkdev);
> + return 0;
> +}
> +
> +static int rk_crypto_pm_resume(struct device *dev)
> +{
> + struct rk_crypto_info *rkdev = dev_get_drvdata(dev);
> +
> + return rk_crypto_enable_clk(rkdev);
> +}
> +
> +static const struct dev_pm_ops rk_crypto_pm_ops = {
> + SET_RUNTIME_PM_OPS(rk_crypto_pm_suspend, rk_crypto_pm_resume, NULL)
> +};
> +
> +static int rk_crypto_pm_init(struct rk_crypto_info *rkdev)
> +{
> + int err;
> +
> + pm_runtime_use_autosuspend(rkdev->dev);
> + pm_runtime_set_autosuspend_delay(rkdev->dev, 2000);
> +
> + err = pm_runtime_set_suspended(rkdev->dev);
> + if (err)
> + return err;
> + pm_runtime_enable(rkdev->dev);
> + return err;
> +}
> +
> +static void rk_crypto_pm_exit(struct rk_crypto_info *rkdev)
> +{
> + pm_runtime_disable(rkdev->dev);
> +}
> +
> static irqreturn_t rk_crypto_irq_handle(int irq, void *dev_id)
> {
> struct rk_crypto_info *dev = platform_get_drvdata(dev_id);
> @@ -259,7 +301,9 @@ static int rk_crypto_probe(struct platform_device *pdev)
> crypto_engine_start(crypto_info->engine);
> init_completion(&crypto_info->complete);
>
> - rk_crypto_enable_clk(crypto_info);
> + err = rk_crypto_pm_init(crypto_info);
> + if (err)
> + goto err_crypto;
>
> err = rk_crypto_register(crypto_info);
> if (err) {
> @@ -280,6 +324,7 @@ static int rk_crypto_probe(struct platform_device *pdev)
> return 0;
>
> err_register_alg:
> + rk_crypto_pm_exit(crypto_info);
> err_crypto:
> dev_err(dev, "Crypto Accelerator not successfully registered\n");
> return err;
> @@ -293,7 +338,7 @@ static int rk_crypto_remove(struct platform_device *pdev)
> debugfs_remove_recursive(crypto_tmp->dbgfs_dir);
> #endif
> rk_crypto_unregister();
> - rk_crypto_disable_clk(crypto_tmp);
> + rk_crypto_pm_exit(crypto_tmp);
> return 0;
> }
>
> @@ -302,6 +347,7 @@ static struct platform_driver crypto_driver = {
> .remove = rk_crypto_remove,
> .driver = {
> .name = "rk3288-crypto",
> + .pm = &rk_crypto_pm_ops,
> .of_match_table = crypto_of_id_table,
> },
> };
> diff --git a/drivers/crypto/rockchip/rk3288_crypto.h b/drivers/crypto/rockchip/rk3288_crypto.h
> index e2a6d735f2e2..06b2d9f52a80 100644
> --- a/drivers/crypto/rockchip/rk3288_crypto.h
> +++ b/drivers/crypto/rockchip/rk3288_crypto.h
> @@ -9,6 +9,7 @@
> #include <linux/interrupt.h>
> #include <linux/debugfs.h>
> #include <linux/delay.h>
> +#include <linux/pm_runtime.h>
> #include <linux/scatterlist.h>
> #include <crypto/engine.h>
> #include <crypto/internal/hash.h>
> diff --git a/drivers/crypto/rockchip/rk3288_crypto_ahash.c b/drivers/crypto/rockchip/rk3288_crypto_ahash.c
> index 8856c6226be6..a41e21c7141b 100644
> --- a/drivers/crypto/rockchip/rk3288_crypto_ahash.c
> +++ b/drivers/crypto/rockchip/rk3288_crypto_ahash.c
> @@ -328,6 +328,7 @@ static int rk_cra_hash_init(struct crypto_tfm *tfm)
> struct ahash_alg *alg = __crypto_ahash_alg(tfm->__crt_alg);
>
> const char *alg_name = crypto_tfm_alg_name(tfm);
> + int err;
>
> algt = container_of(alg, struct rk_crypto_tmp, alg.hash);
>
> @@ -349,7 +350,16 @@ static int rk_cra_hash_init(struct crypto_tfm *tfm)
> tctx->enginectx.op.prepare_request = rk_hash_prepare;
> tctx->enginectx.op.unprepare_request = rk_hash_unprepare;
>
> + err = pm_runtime_get_sync(tctx->dev->dev);

pm_runtime_resume_and_get() ? The error handling is nicer with that.

> + if (err < 0)
> + goto error_pm;
> +
> return 0;
> +error_pm:
> + pm_runtime_put_noidle(tctx->dev->dev);
> + crypto_free_ahash(tctx->fallback_tfm);
> +
> + return err;
> }
>
> static void rk_cra_hash_exit(struct crypto_tfm *tfm)
> @@ -357,6 +367,7 @@ static void rk_cra_hash_exit(struct crypto_tfm *tfm)
> struct rk_ahash_ctx *tctx = crypto_tfm_ctx(tfm);
>
> crypto_free_ahash(tctx->fallback_tfm);
> + pm_runtime_put_sync_suspend(tctx->dev->dev);

Why use sync_suspend here? Could this be pm_runtime_put_autosuspend()?

> }
>
> struct rk_crypto_tmp rk_ahash_sha1 = {
> diff --git a/drivers/crypto/rockchip/rk3288_crypto_skcipher.c b/drivers/crypto/rockchip/rk3288_crypto_skcipher.c
> index a8cfb520eaf8..55efda6ea3e7 100644
> --- a/drivers/crypto/rockchip/rk3288_crypto_skcipher.c
> +++ b/drivers/crypto/rockchip/rk3288_crypto_skcipher.c
> @@ -458,6 +458,7 @@ static int rk_ablk_init_tfm(struct crypto_skcipher *tfm)
> struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
> const char *name = crypto_tfm_alg_name(&tfm->base);
> struct rk_crypto_tmp *algt;
> + int err;
>
> algt = container_of(alg, struct rk_crypto_tmp, alg.skcipher);
>
> @@ -475,7 +476,15 @@ static int rk_ablk_init_tfm(struct crypto_skcipher *tfm)
>
> ctx->enginectx.op.do_one_request = rk_cipher_run;
>
> + err = pm_runtime_get_sync(ctx->dev->dev);

Another place for pm_runtime_resume_and_get() ?

> + if (err < 0)
> + goto error_pm;
> +
> return 0;
> +error_pm:
> + pm_runtime_put_noidle(ctx->dev->dev);
> + crypto_free_skcipher(ctx->fallback_tfm);
> + return err;
> }
>
> static void rk_ablk_exit_tfm(struct crypto_skcipher *tfm)
> @@ -484,6 +493,7 @@ static void rk_ablk_exit_tfm(struct crypto_skcipher *tfm)
>
> memzero_explicit(ctx->key, ctx->keylen);
> crypto_free_skcipher(ctx->fallback_tfm);
> + pm_runtime_put_sync_suspend(ctx->dev->dev);

Again, can this be pm_runtime_put_autosuspend() ?