Re: [RFC PATCH v1] scsi: ufs-mediatek: add inline encryption support

[Eric Biggers]

On Mon, Mar 02, 2020 at 05:11:38PM +0800, Stanley Chu wrote:
> Add inline encryption support to ufs-mediatek.
> 
> The standards-compliant parts, such as querying the crypto capabilities
> and enabling crypto for individual UFS requests, are already handled by
> ufshcd-crypto.c, which itself is wired into the blk-crypto framework.
> 
> However MediaTek UFS host requires a vendor-specific hce_enable operation
> to allow crypto-related registers being accessed normally in kernel.
> After this step, MediaTek UFS host can work as standard-compliant host
> for inline-encryption related functions.
> 
> This patch is rebased to the latest wip-inline-encryption branch in
> Eric Biggers's git:
> https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux.git/

Please don't use a random work-in-progress branch from my git repository (which
hasn't been updated to the v7 patchset yet and will be rebased); use instead:

	Repo: https://git.kernel.org/pub/scm/fs/fscrypt/fscrypt.git
	Tag: inline-encryption-v7

Also, this patch doesn't apply to either branch anyway:

Applying: scsi: ufs-mediatek: add inline encryption support
Using index info to reconstruct a base tree...
error: patch failed: drivers/scsi/ufs/ufs-mediatek.c:15
error: drivers/scsi/ufs/ufs-mediatek.c: patch does not apply
error: patch failed: drivers/scsi/ufs/ufs-mediatek.h:58
error: drivers/scsi/ufs/ufs-mediatek.h: patch does not apply
error: Did you hand edit your patch?

> diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-mediatek.c
> index 53eae5fe2ade..12d01fd3d5e1 100644
> --- a/drivers/scsi/ufs/ufs-mediatek.c
> +++ b/drivers/scsi/ufs/ufs-mediatek.c
> @@ -15,6 +15,7 @@
>  #include <linux/soc/mediatek/mtk_sip_svc.h>
>  
>  #include "ufshcd.h"
> +#include "ufshcd-crypto.h"
>  #include "ufshcd-pltfrm.h"
>  #include "ufs_quirks.h"
>  #include "unipro.h"
> @@ -24,6 +25,9 @@
>  	arm_smccc_smc(MTK_SIP_UFS_CONTROL, \
>  		      cmd, val, 0, 0, 0, 0, 0, &(res))
>  
> +#define ufs_mtk_crypto_ctrl(res, enable) \
> +	ufs_mtk_smc(UFS_MTK_SIP_CRYPTO_CTRL, enable, res)
> +
>  #define ufs_mtk_ref_clk_notify(on, res) \
>  	ufs_mtk_smc(UFS_MTK_SIP_REF_CLK_NOTIFICATION, on, res)
>  
> @@ -66,7 +70,27 @@ static void ufs_mtk_cfg_unipro_cg(struct ufs_hba *hba, bool enable)
>  	}
>  }
>  
> -static int ufs_mtk_bind_mphy(struct ufs_hba *hba)
> +static void ufs_mtk_crypto_enable(struct ufs_hba *hba)
> +{
> +	struct arm_smccc_res res;
> +
> +	ufs_mtk_crypto_ctrl(res, 1);
> +	if (res.a0) {
> +		dev_info(hba->dev, "%s: crypto enable failed, err: %lu\n",
> +			 __func__, res.a0);
> +	}
> +}
> +
> +static int ufs_mtk_hce_enable_notify(struct ufs_hba *hba,
> +				     enum ufs_notify_change_status status)
> +{
> +	if (status == PRE_CHANGE && ufshcd_hba_is_crypto_supported(hba))
> +		ufs_mtk_crypto_enable(hba);
> +
> +	return 0;
> +}
> +
> +int ufs_mtk_bind_mphy(struct ufs_hba *hba)
>  {
>  	struct ufs_mtk_host *host = ufshcd_get_variant(hba);
>  	struct device *dev = hba->dev;
> @@ -494,6 +518,7 @@ static struct ufs_hba_variant_ops ufs_hba_mtk_vops = {
>  	.name                = "mediatek.ufshci",
>  	.init                = ufs_mtk_init,
>  	.setup_clocks        = ufs_mtk_setup_clocks,
> +	.hce_enable_notify   = ufs_mtk_hce_enable_notify,
>  	.link_startup_notify = ufs_mtk_link_startup_notify,
>  	.pwr_change_notify   = ufs_mtk_pwr_change_notify,
>  	.apply_dev_quirks    = ufs_mtk_apply_dev_quirks,
> diff --git a/drivers/scsi/ufs/ufs-mediatek.h b/drivers/scsi/ufs/ufs-mediatek.h
> index fccdd979d6fb..5ebaa59898bf 100644
> --- a/drivers/scsi/ufs/ufs-mediatek.h
> +++ b/drivers/scsi/ufs/ufs-mediatek.h
> @@ -58,6 +58,7 @@
>   */
>  #define MTK_SIP_UFS_CONTROL               MTK_SIP_SMC_CMD(0x276)
>  #define UFS_MTK_SIP_DEVICE_RESET          BIT(1)
> +#define UFS_MTK_SIP_CRYPTO_CTRL           BIT(2)
>  #define UFS_MTK_SIP_REF_CLK_NOTIFICATION  BIT(3)

But if this is all that's needed to get inline crypto working with Mediatek UFS,
that's great news.

Thanks!

- Eric