mmc: cqhci: add support for inline encryption

Add support for eMMC inline encryption using the blk-crypto framework
(Documentation/block/inline-encryption.rst).

eMMC inline encryption support is specified by the upcoming JEDEC eMMC
v5.2 specification.  It is only specified for the CQ interface, not the
non-CQ interface.  Although the eMMC v5.2 specification hasn't been
officially released yet, the crypto support was already agreed on
several years ago, and it was already implemented by at least two major
hardware vendors.  Lots of hardware in the field already supports and
uses it, e.g. Snapdragon 630 to give one example.

eMMC inline encryption support is very similar to the UFS inline
encryption support which was standardized in the UFS v2.1 specification
and was already upstreamed.  The only major difference is that eMMC
limits data unit numbers to 32 bits, unlike UFS's 64 bits.

Like we did with UFS, make the crypto support opt-in by individual
drivers; don't enable it automatically whenever the hardware declares
crypto support.  This is necessary because in every case we've seen,
some extra vendor-specific logic is needed to use the crypto support.

Co-developed-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Satya Tangirala <satyat@google.com>
Reviewed-and-tested-by: Peng Zhou <peng.zhou@mediatek.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20210125183810.198008-5-ebiggers@kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

1 files changed, 79 insertions, 1 deletions

diff --git a/drivers/mmc/host/cqhci.h b/drivers/mmc/host/cqhci.h
index 89bf6adbce8c..8e9e8f5db5bc 100644
--- a/drivers/mmc/host/cqhci.h
+++ b/drivers/mmc/host/cqhci.h
@@ -22,10 +22,13 @@
 
 /* capabilities */
 #define CQHCI_CAP			0x04
+#define CQHCI_CAP_CS			0x10000000 /* Crypto Support */
+
 /* configuration */
 #define CQHCI_CFG			0x08
 #define CQHCI_DCMD			0x00001000
 #define CQHCI_TASK_DESC_SZ		0x00000100
+#define CQHCI_CRYPTO_GENERAL_ENABLE	0x00000002
 #define CQHCI_ENABLE			0x00000001
 
 /* control */
@@ -39,8 +42,11 @@
 #define CQHCI_IS_TCC			BIT(1)
 #define CQHCI_IS_RED			BIT(2)
 #define CQHCI_IS_TCL			BIT(3)
+#define CQHCI_IS_GCE			BIT(4) /* General Crypto Error */
+#define CQHCI_IS_ICCE			BIT(5) /* Invalid Crypto Config Error */
 
-#define CQHCI_IS_MASK (CQHCI_IS_TCC | CQHCI_IS_RED)
+#define CQHCI_IS_MASK (CQHCI_IS_TCC | CQHCI_IS_RED | \
+		       CQHCI_IS_GCE | CQHCI_IS_ICCE)
 
 /* interrupt status enable */
 #define CQHCI_ISTE			0x14
@@ -78,6 +84,9 @@
 /* task clear */
 #define CQHCI_TCLR			0x38
 
+/* task descriptor processing error */
+#define CQHCI_TDPE			0x3c
+
 /* send status config 1 */
 #define CQHCI_SSC1			0x40
 #define CQHCI_SSC1_CBC_MASK		GENMASK(19, 16)
@@ -107,6 +116,10 @@
 /* command response argument */
 #define CQHCI_CRA			0x5C
 
+/* crypto capabilities */
+#define CQHCI_CCAP			0x100
+#define CQHCI_CRYPTOCAP			0x104
+
 #define CQHCI_INT_ALL			0xF
 #define CQHCI_IC_DEFAULT_ICCTH		31
 #define CQHCI_IC_DEFAULT_ICTOVAL	1
@@ -133,11 +146,70 @@
 #define CQHCI_CMD_TIMING(x)		(((x) & 1) << 22)
 #define CQHCI_RESP_TYPE(x)		(((x) & 0x3) << 23)
 
+/* crypto task descriptor fields (for bits 64-127 of task descriptor) */
+#define CQHCI_CRYPTO_ENABLE_BIT		(1ULL << 47)
+#define CQHCI_CRYPTO_KEYSLOT(x)		((u64)(x) << 32)
+
 /* transfer descriptor fields */
 #define CQHCI_DAT_LENGTH(x)		(((x) & 0xFFFF) << 16)
 #define CQHCI_DAT_ADDR_LO(x)		(((x) & 0xFFFFFFFF) << 32)
 #define CQHCI_DAT_ADDR_HI(x)		(((x) & 0xFFFFFFFF) << 0)
 
+/* CCAP - Crypto Capability 100h */
+union cqhci_crypto_capabilities {
+	__le32 reg_val;
+	struct {
+		u8 num_crypto_cap;
+		u8 config_count;
+		u8 reserved;
+		u8 config_array_ptr;
+	};
+};
+
+enum cqhci_crypto_key_size {
+	CQHCI_CRYPTO_KEY_SIZE_INVALID	= 0,
+	CQHCI_CRYPTO_KEY_SIZE_128	= 1,
+	CQHCI_CRYPTO_KEY_SIZE_192	= 2,
+	CQHCI_CRYPTO_KEY_SIZE_256	= 3,
+	CQHCI_CRYPTO_KEY_SIZE_512	= 4,
+};
+
+enum cqhci_crypto_alg {
+	CQHCI_CRYPTO_ALG_AES_XTS		= 0,
+	CQHCI_CRYPTO_ALG_BITLOCKER_AES_CBC	= 1,
+	CQHCI_CRYPTO_ALG_AES_ECB		= 2,
+	CQHCI_CRYPTO_ALG_ESSIV_AES_CBC		= 3,
+};
+
+/* x-CRYPTOCAP - Crypto Capability X */
+union cqhci_crypto_cap_entry {
+	__le32 reg_val;
+	struct {
+		u8 algorithm_id;
+		u8 sdus_mask; /* Supported data unit size mask */
+		u8 key_size;
+		u8 reserved;
+	};
+};
+
+#define CQHCI_CRYPTO_CONFIGURATION_ENABLE (1 << 7)
+#define CQHCI_CRYPTO_KEY_MAX_SIZE 64
+/* x-CRYPTOCFG - Crypto Configuration X */
+union cqhci_crypto_cfg_entry {
+	__le32 reg_val[32];
+	struct {
+		u8 crypto_key[CQHCI_CRYPTO_KEY_MAX_SIZE];
+		u8 data_unit_size;
+		u8 crypto_cap_idx;
+		u8 reserved_1;
+		u8 config_enable;
+		u8 reserved_multi_host;
+		u8 reserved_2;
+		u8 vsb[2];
+		u8 reserved_3[56];
+	};
+};
+
 struct cqhci_host_ops;
 struct mmc_host;
 struct mmc_request;
@@ -196,6 +268,12 @@ struct cqhci_host {
 	struct completion halt_comp;
 	wait_queue_head_t wait_queue;
 	struct cqhci_slot *slot;
+
+#ifdef CONFIG_MMC_CRYPTO
+	union cqhci_crypto_capabilities crypto_capabilities;
+	union cqhci_crypto_cap_entry *crypto_cap_array;
+	u32 crypto_cfg_register;
+#endif
 };
 
 struct cqhci_host_ops {