Re: [PATCH v5 3/5] crypto: ccp - Add an S4 restore flow

[Tom Lendacky <thomas.lendacky@amd.com>]

On 1/11/26 23:36, Mario Limonciello (AMD) wrote:
> The system will have lost power during S4.  The ring used for TEE
> communications needs to be initialized before use.
> 
> Fixes: f892a21f51162 ("crypto: ccp - use generic power management")
> Reported-by: Lars Francke <lars.francke@gmail.com>
> Closes: https://lore.kernel.org/platform-driver-x86/CAD-Ua_gfJnQSo8ucS_7ZwzuhoBRJ14zXP7s8b-zX3ZcxcyWePw@mail.gmail.com/
> Tested-by: Yijun Shen <Yijun.Shen@Dell.com>
> Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
> ---
> v5:
>  * Fix return for psp_restore() (LKP robot, Shyam)
> v4:
>  * Add tag (Yijun)
>  * Remove blank line (Ilpo)
>  * Adjust whitespace in psp_restore() (Ilpo)
> ---
>  drivers/crypto/ccp/psp-dev.c | 11 +++++++++++
>  drivers/crypto/ccp/sp-dev.h  |  2 ++
>  drivers/crypto/ccp/sp-pci.c  | 24 +++++++++++++++++++++++-
>  drivers/crypto/ccp/tee-dev.c |  5 +++++
>  drivers/crypto/ccp/tee-dev.h |  1 +
>  5 files changed, 42 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
> index 9e21da0e298ad..5c7f7e02a7d8a 100644
> --- a/drivers/crypto/ccp/psp-dev.c
> +++ b/drivers/crypto/ccp/psp-dev.c
> @@ -351,6 +351,17 @@ struct psp_device *psp_get_master_device(void)
>  	return sp ? sp->psp_data : NULL;
>  }
>  
> +int psp_restore(struct sp_device *sp)
> +{
> +	struct psp_device *psp = sp->psp_data;
> +	int ret = 0;
> +
> +	if (psp->tee_data)
> +		ret = tee_restore(psp);
> +
> +	return ret;
> +}
> +
>  void psp_pci_init(void)
>  {
>  	psp_master = psp_get_master_device();
> diff --git a/drivers/crypto/ccp/sp-dev.h b/drivers/crypto/ccp/sp-dev.h
> index 1335a83fe052e..0deea1a399e47 100644
> --- a/drivers/crypto/ccp/sp-dev.h
> +++ b/drivers/crypto/ccp/sp-dev.h
> @@ -174,6 +174,7 @@ int psp_dev_init(struct sp_device *sp);
>  void psp_pci_init(void);
>  void psp_dev_destroy(struct sp_device *sp);
>  void psp_pci_exit(void);
> +int psp_restore(struct sp_device *sp);
>  
>  #else /* !CONFIG_CRYPTO_DEV_SP_PSP */
>  
> @@ -181,6 +182,7 @@ static inline int psp_dev_init(struct sp_device *sp) { return 0; }
>  static inline void psp_pci_init(void) { }
>  static inline void psp_dev_destroy(struct sp_device *sp) { }
>  static inline void psp_pci_exit(void) { }
> +static inline int psp_restore(struct sp_device *sp) { return 0; }
>  
>  #endif /* CONFIG_CRYPTO_DEV_SP_PSP */
>  
> diff --git a/drivers/crypto/ccp/sp-pci.c b/drivers/crypto/ccp/sp-pci.c
> index 8891ceee1d7d0..931ec6bf2cec6 100644
> --- a/drivers/crypto/ccp/sp-pci.c
> +++ b/drivers/crypto/ccp/sp-pci.c
> @@ -353,6 +353,21 @@ static int __maybe_unused sp_pci_resume(struct device *dev)
>  	return sp_resume(sp);
>  }
>  
> +static int __maybe_unused sp_pci_restore(struct device *dev)
> +{
> +	struct sp_device *sp = dev_get_drvdata(dev);
> +
> +#ifdef CONFIG_CRYPTO_DEV_SP_PSP

This isn't needed since you have the "#else" definition in sp-dev.h.

> +	if (sp->psp_data) {
> +		int ret = psp_restore(sp);
> +

Remove blank line.

> +		if (ret)
> +			return ret;
> +	}
> +#endif

This isn't the way the other functions work. This function should just
be calling to sp_resume() and then sp_resume() should call psp_restore()
(or psp_dev_restore() ?) if the psp_data is present.

And if you need to distinguish between the resume and restore case in
sp_resume(), then it sounds like you need an sp_restore().

Thanks,
Tom

> +	return sp_resume(sp);
> +}
> +
>  #ifdef CONFIG_CRYPTO_DEV_SP_PSP
>  static const struct sev_vdata sevv1 = {
>  	.cmdresp_reg		= 0x10580,	/* C2PMSG_32 */
> @@ -563,7 +578,14 @@ static const struct pci_device_id sp_pci_table[] = {
>  };
>  MODULE_DEVICE_TABLE(pci, sp_pci_table);
>  
> -static SIMPLE_DEV_PM_OPS(sp_pci_pm_ops, sp_pci_suspend, sp_pci_resume);
> +static const struct dev_pm_ops sp_pci_pm_ops = {
> +	.suspend = pm_sleep_ptr(sp_pci_suspend),
> +	.resume = pm_sleep_ptr(sp_pci_resume),
> +	.freeze = pm_sleep_ptr(sp_pci_suspend),
> +	.thaw = pm_sleep_ptr(sp_pci_resume),
> +	.poweroff = pm_sleep_ptr(sp_pci_suspend),
> +	.restore_early = pm_sleep_ptr(sp_pci_restore),
> +};
>  
>  static struct pci_driver sp_pci_driver = {
>  	.name = "ccp",
> diff --git a/drivers/crypto/ccp/tee-dev.c b/drivers/crypto/ccp/tee-dev.c
> index af881daa5855b..11c4b05e2f3a2 100644
> --- a/drivers/crypto/ccp/tee-dev.c
> +++ b/drivers/crypto/ccp/tee-dev.c
> @@ -366,3 +366,8 @@ int psp_check_tee_status(void)
>  	return 0;
>  }
>  EXPORT_SYMBOL(psp_check_tee_status);
> +
> +int tee_restore(struct psp_device *psp)
> +{
> +	return tee_init_ring(psp->tee_data);
> +}
> diff --git a/drivers/crypto/ccp/tee-dev.h b/drivers/crypto/ccp/tee-dev.h
> index ea9a2b7c05f57..c23416cb7bb37 100644
> --- a/drivers/crypto/ccp/tee-dev.h
> +++ b/drivers/crypto/ccp/tee-dev.h
> @@ -111,5 +111,6 @@ struct tee_ring_cmd {
>  
>  int tee_dev_init(struct psp_device *psp);
>  void tee_dev_destroy(struct psp_device *psp);
> +int tee_restore(struct psp_device *psp);
>  
>  #endif /* __TEE_DEV_H__ */