[PATCH v5 5/9] mmc: cqhci: add cqhci_host_ops::program_key
From: Eric Biggers <ebiggers@kernel.org>
Date: 2021-01-21 09:06:00
Also in:
linux-arm-msm, linux-fscrypt, linux-mmc
Subsystem:
emmc cmdq host controller interface (cqhci) driver, multimedia card (mmc), secure digital (sd) and sdio subsystem, the rest · Maintainers:
Adrian Hunter, Asutosh Das, Ulf Hansson, Linus Torvalds
From: Eric Biggers <redacted>
On Snapdragon SoCs, the Linux kernel isn't permitted to directly access
the standard CQHCI crypto configuration registers. Instead, programming
and evicting keys must be done through vendor-specific SMC calls.
To support this hardware, add a ->program_key() method to
'struct cqhci_host_ops'. This allows overriding the standard CQHCI
crypto key programming / eviction procedure.
This is inspired by the corresponding UFS crypto support, which uses
these same SMC calls. See commit 1bc726e26ef3 ("scsi: ufs: Add
program_key() variant op").
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Satya Tangirala <redacted>
Reviewed-and-tested-by: Peng Zhou [off-list ref]
Signed-off-by: Eric Biggers <redacted>
---
drivers/mmc/host/cqhci-crypto.c | 22 +++++++++++++---------
drivers/mmc/host/cqhci.h | 4 ++++
2 files changed, 17 insertions(+), 9 deletions(-)
diff --git a/drivers/mmc/host/cqhci-crypto.c b/drivers/mmc/host/cqhci-crypto.c
index 0e2a9dcac6308..6419cfbb4ab78 100644
--- a/drivers/mmc/host/cqhci-crypto.c
+++ b/drivers/mmc/host/cqhci-crypto.c@@ -30,13 +30,16 @@ cqhci_host_from_ksm(struct blk_keyslot_manager *ksm) return mmc->cqe_private; } -static void cqhci_crypto_program_key(struct cqhci_host *cq_host, - const union cqhci_crypto_cfg_entry *cfg, - int slot) +static int cqhci_crypto_program_key(struct cqhci_host *cq_host, + const union cqhci_crypto_cfg_entry *cfg, + int slot) { u32 slot_offset = cq_host->crypto_cfg_register + slot * sizeof(*cfg); int i; + if (cq_host->ops->program_key) + return cq_host->ops->program_key(cq_host, cfg, slot); + /* Clear CFGE */ cqhci_writel(cq_host, 0, slot_offset + 16 * sizeof(cfg->reg_val[0]));
@@ -51,6 +54,7 @@ static void cqhci_crypto_program_key(struct cqhci_host *cq_host, /* Write dword 16, which includes the new value of CFGE */ cqhci_writel(cq_host, le32_to_cpu(cfg->reg_val[16]), slot_offset + 16 * sizeof(cfg->reg_val[0])); + return 0; } static int cqhci_crypto_keyslot_program(struct blk_keyslot_manager *ksm,
@@ -67,6 +71,7 @@ static int cqhci_crypto_keyslot_program(struct blk_keyslot_manager *ksm, int i; int cap_idx = -1; union cqhci_crypto_cfg_entry cfg = {}; + int err; BUILD_BUG_ON(CQHCI_CRYPTO_KEY_SIZE_INVALID != 0); for (i = 0; i < cq_host->crypto_capabilities.num_crypto_cap; i++) {
@@ -93,13 +98,13 @@ static int cqhci_crypto_keyslot_program(struct blk_keyslot_manager *ksm, memcpy(cfg.crypto_key, key->raw, key->size); } - cqhci_crypto_program_key(cq_host, &cfg, slot); + err = cqhci_crypto_program_key(cq_host, &cfg, slot); memzero_explicit(&cfg, sizeof(cfg)); - return 0; + return err; } -static void cqhci_crypto_clear_keyslot(struct cqhci_host *cq_host, int slot) +static int cqhci_crypto_clear_keyslot(struct cqhci_host *cq_host, int slot) { /* * Clear the crypto cfg on the device. Clearing CFGE
@@ -107,7 +112,7 @@ static void cqhci_crypto_clear_keyslot(struct cqhci_host *cq_host, int slot) */ union cqhci_crypto_cfg_entry cfg = {}; - cqhci_crypto_program_key(cq_host, &cfg, slot); + return cqhci_crypto_program_key(cq_host, &cfg, slot); } static int cqhci_crypto_keyslot_evict(struct blk_keyslot_manager *ksm,
@@ -116,8 +121,7 @@ static int cqhci_crypto_keyslot_evict(struct blk_keyslot_manager *ksm, { struct cqhci_host *cq_host = cqhci_host_from_ksm(ksm); - cqhci_crypto_clear_keyslot(cq_host, slot); - return 0; + return cqhci_crypto_clear_keyslot(cq_host, slot); } /*
diff --git a/drivers/mmc/host/cqhci.h b/drivers/mmc/host/cqhci.h
index 8e9e8f5db5bcc..ba9387ed90eb6 100644
--- a/drivers/mmc/host/cqhci.h
+++ b/drivers/mmc/host/cqhci.h@@ -286,6 +286,10 @@ struct cqhci_host_ops { u64 *data); void (*pre_enable)(struct mmc_host *mmc); void (*post_disable)(struct mmc_host *mmc); +#ifdef CONFIG_MMC_CRYPTO + int (*program_key)(struct cqhci_host *cq_host, + const union cqhci_crypto_cfg_entry *cfg, int slot); +#endif }; static inline void cqhci_writel(struct cqhci_host *host, u32 val, int reg)
--
2.30.0