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kernel/linux-rt-4.4.41/drivers/crypto/talitos.h 15.2 KB
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  /*
   * Freescale SEC (talitos) device register and descriptor header defines
   *
   * Copyright (c) 2006-2011 Freescale Semiconductor, Inc.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. The name of the author may not be used to endorse or promote products
   *    derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   *
   */
  
  #define TALITOS_TIMEOUT 100000
  #define TALITOS1_MAX_DATA_LEN 32768
  #define TALITOS2_MAX_DATA_LEN 65535
  
  #define DESC_TYPE(desc_hdr) ((be32_to_cpu(desc_hdr) >> 3) & 0x1f)
  #define PRIMARY_EU(desc_hdr) ((be32_to_cpu(desc_hdr) >> 28) & 0xf)
  #define SECONDARY_EU(desc_hdr) ((be32_to_cpu(desc_hdr) >> 16) & 0xf)
  
  /* descriptor pointer entry */
  struct talitos_ptr {
  	union {
  		struct {		/* SEC2 format */
  			__be16 len;     /* length */
  			u8 j_extent;    /* jump to sg link table and/or extent*/
  			u8 eptr;        /* extended address */
  		};
  		struct {			/* SEC1 format */
  			__be16 res;
  			__be16 len1;	/* length */
  		};
  	};
  	__be32 ptr;     /* address */
  };
  
  static const struct talitos_ptr zero_entry;
  
  /* descriptor */
  struct talitos_desc {
  	__be32 hdr;                     /* header high bits */
  	union {
  		__be32 hdr_lo;		/* header low bits */
  		__be32 hdr1;		/* header for SEC1 */
  	};
  	struct talitos_ptr ptr[7];      /* ptr/len pair array */
  	__be32 next_desc;		/* next descriptor (SEC1) */
  };
  
  #define TALITOS_DESC_SIZE	(sizeof(struct talitos_desc) - sizeof(__be32))
  
  /**
   * talitos_request - descriptor submission request
   * @desc: descriptor pointer (kernel virtual)
   * @dma_desc: descriptor's physical bus address
   * @callback: whom to call when descriptor processing is done
   * @context: caller context (optional)
   */
  struct talitos_request {
  	struct talitos_desc *desc;
  	dma_addr_t dma_desc;
  	void (*callback) (struct device *dev, struct talitos_desc *desc,
  			  void *context, int error);
  	void *context;
  };
  
  /* per-channel fifo management */
  struct talitos_channel {
  	void __iomem *reg;
  
  	/* request fifo */
  	struct talitos_request *fifo;
  
  	/* number of requests pending in channel h/w fifo */
  	atomic_t submit_count ____cacheline_aligned;
  
  	/* request submission (head) lock */
  	spinlock_t head_lock ____cacheline_aligned;
  	/* index to next free descriptor request */
  	int head;
  
  	/* request release (tail) lock */
  	spinlock_t tail_lock ____cacheline_aligned;
  	/* index to next in-progress/done descriptor request */
  	int tail;
  };
  
  struct talitos_private {
  	struct device *dev;
  	struct platform_device *ofdev;
  	void __iomem *reg;
  	void __iomem *reg_deu;
  	void __iomem *reg_aesu;
  	void __iomem *reg_mdeu;
  	void __iomem *reg_afeu;
  	void __iomem *reg_rngu;
  	void __iomem *reg_pkeu;
  	void __iomem *reg_keu;
  	void __iomem *reg_crcu;
  	int irq[2];
  
  	/* SEC global registers lock  */
  	spinlock_t reg_lock ____cacheline_aligned;
  
  	/* SEC version geometry (from device tree node) */
  	unsigned int num_channels;
  	unsigned int chfifo_len;
  	unsigned int exec_units;
  	unsigned int desc_types;
  
  	/* SEC Compatibility info */
  	unsigned long features;
  
  	/*
  	 * length of the request fifo
  	 * fifo_len is chfifo_len rounded up to next power of 2
  	 * so we can use bitwise ops to wrap
  	 */
  	unsigned int fifo_len;
  
  	struct talitos_channel *chan;
  
  	/* next channel to be assigned next incoming descriptor */
  	atomic_t last_chan ____cacheline_aligned;
  
  	/* request callback tasklet */
  	struct tasklet_struct done_task[2];
  
  	/* list of registered algorithms */
  	struct list_head alg_list;
  
  	/* hwrng device */
  	struct hwrng rng;
  	bool rng_registered;
  };
  
  extern int talitos_submit(struct device *dev, int ch, struct talitos_desc *desc,
  			  void (*callback)(struct device *dev,
  					   struct talitos_desc *desc,
  					   void *context, int error),
  			  void *context);
  
  /* .features flag */
  #define TALITOS_FTR_SRC_LINK_TBL_LEN_INCLUDES_EXTENT 0x00000001
  #define TALITOS_FTR_HW_AUTH_CHECK 0x00000002
  #define TALITOS_FTR_SHA224_HWINIT 0x00000004
  #define TALITOS_FTR_HMAC_OK 0x00000008
  #define TALITOS_FTR_SEC1 0x00000010
  
  /*
   * If both CONFIG_CRYPTO_DEV_TALITOS1 and CONFIG_CRYPTO_DEV_TALITOS2 are
   * defined, we check the features which are set according to the device tree.
   * Otherwise, we answer true or false directly
   */
  static inline bool has_ftr_sec1(struct talitos_private *priv)
  {
  #if defined(CONFIG_CRYPTO_DEV_TALITOS1) && defined(CONFIG_CRYPTO_DEV_TALITOS2)
  	return priv->features & TALITOS_FTR_SEC1 ? true : false;
  #elif defined(CONFIG_CRYPTO_DEV_TALITOS1)
  	return true;
  #else
  	return false;
  #endif
  }
  
  /*
   * TALITOS_xxx_LO addresses point to the low data bits (32-63) of the register
   */
  
  #define ISR1_FORMAT(x)			(((x) << 28) | ((x) << 16))
  #define ISR2_FORMAT(x)			(((x) << 4) | (x))
  
  /* global register offset addresses */
  #define TALITOS_MCR			0x1030  /* master control register */
  #define   TALITOS_MCR_RCA0		(1 << 15) /* remap channel 0 */
  #define   TALITOS_MCR_RCA1		(1 << 14) /* remap channel 1 */
  #define   TALITOS_MCR_RCA2		(1 << 13) /* remap channel 2 */
  #define   TALITOS_MCR_RCA3		(1 << 12) /* remap channel 3 */
  #define   TALITOS1_MCR_SWR		0x1000000     /* s/w reset */
  #define   TALITOS2_MCR_SWR		0x1     /* s/w reset */
  #define TALITOS_MCR_LO			0x1034
  #define TALITOS_IMR			0x1008  /* interrupt mask register */
  /* enable channel IRQs */
  #define   TALITOS1_IMR_INIT		ISR1_FORMAT(0xf)
  #define   TALITOS1_IMR_DONE		ISR1_FORMAT(0x5) /* done IRQs */
  /* enable channel IRQs */
  #define   TALITOS2_IMR_INIT		(ISR2_FORMAT(0xf) | 0x10000)
  #define   TALITOS2_IMR_DONE		ISR1_FORMAT(0x5) /* done IRQs */
  #define TALITOS_IMR_LO			0x100C
  #define   TALITOS1_IMR_LO_INIT		0x2000000 /* allow RNGU error IRQs */
  #define   TALITOS2_IMR_LO_INIT		0x20000 /* allow RNGU error IRQs */
  #define TALITOS_ISR			0x1010  /* interrupt status register */
  #define   TALITOS1_ISR_4CHERR		ISR1_FORMAT(0xa) /* 4 ch errors mask */
  #define   TALITOS1_ISR_4CHDONE		ISR1_FORMAT(0x5) /* 4 ch done mask */
  #define   TALITOS1_ISR_TEA_ERR		0x00000040
  #define   TALITOS2_ISR_4CHERR		ISR2_FORMAT(0xa) /* 4 ch errors mask */
  #define   TALITOS2_ISR_4CHDONE		ISR2_FORMAT(0x5) /* 4 ch done mask */
  #define   TALITOS2_ISR_CH_0_2_ERR	ISR2_FORMAT(0x2) /* ch 0, 2 err mask */
  #define   TALITOS2_ISR_CH_0_2_DONE	ISR2_FORMAT(0x1) /* ch 0, 2 done mask */
  #define   TALITOS2_ISR_CH_1_3_ERR	ISR2_FORMAT(0x8) /* ch 1, 3 err mask */
  #define   TALITOS2_ISR_CH_1_3_DONE	ISR2_FORMAT(0x4) /* ch 1, 3 done mask */
  #define TALITOS_ISR_LO			0x1014
  #define TALITOS_ICR			0x1018  /* interrupt clear register */
  #define TALITOS_ICR_LO			0x101C
  
  /* channel register address stride */
  #define TALITOS_CH_BASE_OFFSET		0x1000	/* default channel map base */
  #define TALITOS1_CH_STRIDE		0x1000
  #define TALITOS2_CH_STRIDE		0x100
  
  /* channel configuration register  */
  #define TALITOS_CCCR			0x8
  #define   TALITOS2_CCCR_CONT		0x2    /* channel continue on SEC2 */
  #define   TALITOS2_CCCR_RESET		0x1    /* channel reset on SEC2 */
  #define TALITOS_CCCR_LO			0xc
  #define   TALITOS_CCCR_LO_IWSE		0x80   /* chan. ICCR writeback enab. */
  #define   TALITOS_CCCR_LO_EAE		0x20   /* extended address enable */
  #define   TALITOS_CCCR_LO_CDWE		0x10   /* chan. done writeback enab. */
  #define   TALITOS_CCCR_LO_NT		0x4    /* notification type */
  #define   TALITOS_CCCR_LO_CDIE		0x2    /* channel done IRQ enable */
  #define   TALITOS1_CCCR_LO_RESET	0x1    /* channel reset on SEC1 */
  
  /* CCPSR: channel pointer status register */
  #define TALITOS_CCPSR			0x10
  #define TALITOS_CCPSR_LO		0x14
  #define   TALITOS_CCPSR_LO_DOF		0x8000 /* double FF write oflow error */
  #define   TALITOS_CCPSR_LO_SOF		0x4000 /* single FF write oflow error */
  #define   TALITOS_CCPSR_LO_MDTE		0x2000 /* master data transfer error */
  #define   TALITOS_CCPSR_LO_SGDLZ	0x1000 /* s/g data len zero error */
  #define   TALITOS_CCPSR_LO_FPZ		0x0800 /* fetch ptr zero error */
  #define   TALITOS_CCPSR_LO_IDH		0x0400 /* illegal desc hdr error */
  #define   TALITOS_CCPSR_LO_IEU		0x0200 /* invalid EU error */
  #define   TALITOS_CCPSR_LO_EU		0x0100 /* EU error detected */
  #define   TALITOS_CCPSR_LO_GB		0x0080 /* gather boundary error */
  #define   TALITOS_CCPSR_LO_GRL		0x0040 /* gather return/length error */
  #define   TALITOS_CCPSR_LO_SB		0x0020 /* scatter boundary error */
  #define   TALITOS_CCPSR_LO_SRL		0x0010 /* scatter return/length error */
  
  /* channel fetch fifo register */
  #define TALITOS_FF			0x48
  #define TALITOS_FF_LO			0x4c
  
  /* current descriptor pointer register */
  #define TALITOS_CDPR			0x40
  #define TALITOS_CDPR_LO			0x44
  
  /* descriptor buffer register */
  #define TALITOS_DESCBUF			0x80
  #define TALITOS_DESCBUF_LO		0x84
  
  /* gather link table */
  #define TALITOS_GATHER			0xc0
  #define TALITOS_GATHER_LO		0xc4
  
  /* scatter link table */
  #define TALITOS_SCATTER			0xe0
  #define TALITOS_SCATTER_LO		0xe4
  
  /* execution unit registers base */
  #define TALITOS2_DEU			0x2000
  #define TALITOS2_AESU			0x4000
  #define TALITOS2_MDEU			0x6000
  #define TALITOS2_AFEU			0x8000
  #define TALITOS2_RNGU			0xa000
  #define TALITOS2_PKEU			0xc000
  #define TALITOS2_KEU			0xe000
  #define TALITOS2_CRCU			0xf000
  
  #define TALITOS12_AESU			0x4000
  #define TALITOS12_DEU			0x5000
  #define TALITOS12_MDEU			0x6000
  
  #define TALITOS10_AFEU			0x8000
  #define TALITOS10_DEU			0xa000
  #define TALITOS10_MDEU			0xc000
  #define TALITOS10_RNGU			0xe000
  #define TALITOS10_PKEU			0x10000
  #define TALITOS10_AESU			0x12000
  
  /* execution unit interrupt status registers */
  #define TALITOS_EUDSR			0x10	/* data size */
  #define TALITOS_EUDSR_LO		0x14
  #define TALITOS_EURCR			0x18 /* reset control*/
  #define TALITOS_EURCR_LO		0x1c
  #define TALITOS_EUSR			0x28 /* rng status */
  #define TALITOS_EUSR_LO			0x2c
  #define TALITOS_EUISR			0x30
  #define TALITOS_EUISR_LO		0x34
  #define TALITOS_EUICR			0x38 /* int. control */
  #define TALITOS_EUICR_LO		0x3c
  #define TALITOS_EU_FIFO			0x800 /* output FIFO */
  #define TALITOS_EU_FIFO_LO		0x804 /* output FIFO */
  /* DES unit */
  #define   TALITOS1_DEUICR_KPE		0x00200000 /* Key Parity Error */
  /* message digest unit */
  #define   TALITOS_MDEUICR_LO_ICE	0x4000 /* integrity check IRQ enable */
  /* random number unit */
  #define   TALITOS_RNGUSR_LO_RD		0x1	/* reset done */
  #define   TALITOS_RNGUSR_LO_OFL		0xff0000/* output FIFO length */
  #define   TALITOS_RNGURCR_LO_SR		0x1	/* software reset */
  
  #define TALITOS_MDEU_CONTEXT_SIZE_MD5_SHA1_SHA256	0x28
  #define TALITOS_MDEU_CONTEXT_SIZE_SHA384_SHA512		0x48
  
  /*
   * talitos descriptor header (hdr) bits
   */
  
  /* written back when done */
  #define DESC_HDR_DONE			cpu_to_be32(0xff000000)
  #define DESC_HDR_LO_ICCR1_MASK		cpu_to_be32(0x00180000)
  #define DESC_HDR_LO_ICCR1_PASS		cpu_to_be32(0x00080000)
  #define DESC_HDR_LO_ICCR1_FAIL		cpu_to_be32(0x00100000)
  
  /* primary execution unit select */
  #define	DESC_HDR_SEL0_MASK		cpu_to_be32(0xf0000000)
  #define	DESC_HDR_SEL0_AFEU		cpu_to_be32(0x10000000)
  #define	DESC_HDR_SEL0_DEU		cpu_to_be32(0x20000000)
  #define	DESC_HDR_SEL0_MDEUA		cpu_to_be32(0x30000000)
  #define	DESC_HDR_SEL0_MDEUB		cpu_to_be32(0xb0000000)
  #define	DESC_HDR_SEL0_RNG		cpu_to_be32(0x40000000)
  #define	DESC_HDR_SEL0_PKEU		cpu_to_be32(0x50000000)
  #define	DESC_HDR_SEL0_AESU		cpu_to_be32(0x60000000)
  #define	DESC_HDR_SEL0_KEU		cpu_to_be32(0x70000000)
  #define	DESC_HDR_SEL0_CRCU		cpu_to_be32(0x80000000)
  
  /* primary execution unit mode (MODE0) and derivatives */
  #define	DESC_HDR_MODE0_ENCRYPT		cpu_to_be32(0x00100000)
  #define	DESC_HDR_MODE0_AESU_CBC		cpu_to_be32(0x00200000)
  #define	DESC_HDR_MODE0_DEU_CBC		cpu_to_be32(0x00400000)
  #define	DESC_HDR_MODE0_DEU_3DES		cpu_to_be32(0x00200000)
  #define	DESC_HDR_MODE0_MDEU_CONT	cpu_to_be32(0x08000000)
  #define	DESC_HDR_MODE0_MDEU_INIT	cpu_to_be32(0x01000000)
  #define	DESC_HDR_MODE0_MDEU_HMAC	cpu_to_be32(0x00800000)
  #define	DESC_HDR_MODE0_MDEU_PAD		cpu_to_be32(0x00400000)
  #define	DESC_HDR_MODE0_MDEU_SHA224	cpu_to_be32(0x00300000)
  #define	DESC_HDR_MODE0_MDEU_MD5		cpu_to_be32(0x00200000)
  #define	DESC_HDR_MODE0_MDEU_SHA256	cpu_to_be32(0x00100000)
  #define	DESC_HDR_MODE0_MDEU_SHA1	cpu_to_be32(0x00000000)
  #define	DESC_HDR_MODE0_MDEUB_SHA384	cpu_to_be32(0x00000000)
  #define	DESC_HDR_MODE0_MDEUB_SHA512	cpu_to_be32(0x00200000)
  #define	DESC_HDR_MODE0_MDEU_MD5_HMAC	(DESC_HDR_MODE0_MDEU_MD5 | \
  					 DESC_HDR_MODE0_MDEU_HMAC)
  #define	DESC_HDR_MODE0_MDEU_SHA256_HMAC	(DESC_HDR_MODE0_MDEU_SHA256 | \
  					 DESC_HDR_MODE0_MDEU_HMAC)
  #define	DESC_HDR_MODE0_MDEU_SHA1_HMAC	(DESC_HDR_MODE0_MDEU_SHA1 | \
  					 DESC_HDR_MODE0_MDEU_HMAC)
  
  /* secondary execution unit select (SEL1) */
  #define	DESC_HDR_SEL1_MASK		cpu_to_be32(0x000f0000)
  #define	DESC_HDR_SEL1_MDEUA		cpu_to_be32(0x00030000)
  #define	DESC_HDR_SEL1_MDEUB		cpu_to_be32(0x000b0000)
  #define	DESC_HDR_SEL1_CRCU		cpu_to_be32(0x00080000)
  
  /* secondary execution unit mode (MODE1) and derivatives */
  #define	DESC_HDR_MODE1_MDEU_CICV	cpu_to_be32(0x00004000)
  #define	DESC_HDR_MODE1_MDEU_INIT	cpu_to_be32(0x00001000)
  #define	DESC_HDR_MODE1_MDEU_HMAC	cpu_to_be32(0x00000800)
  #define	DESC_HDR_MODE1_MDEU_PAD		cpu_to_be32(0x00000400)
  #define	DESC_HDR_MODE1_MDEU_SHA224	cpu_to_be32(0x00000300)
  #define	DESC_HDR_MODE1_MDEU_MD5		cpu_to_be32(0x00000200)
  #define	DESC_HDR_MODE1_MDEU_SHA256	cpu_to_be32(0x00000100)
  #define	DESC_HDR_MODE1_MDEU_SHA1	cpu_to_be32(0x00000000)
  #define	DESC_HDR_MODE1_MDEUB_SHA384	cpu_to_be32(0x00000000)
  #define	DESC_HDR_MODE1_MDEUB_SHA512	cpu_to_be32(0x00000200)
  #define	DESC_HDR_MODE1_MDEU_MD5_HMAC	(DESC_HDR_MODE1_MDEU_MD5 | \
  					 DESC_HDR_MODE1_MDEU_HMAC)
  #define	DESC_HDR_MODE1_MDEU_SHA256_HMAC	(DESC_HDR_MODE1_MDEU_SHA256 | \
  					 DESC_HDR_MODE1_MDEU_HMAC)
  #define	DESC_HDR_MODE1_MDEU_SHA1_HMAC	(DESC_HDR_MODE1_MDEU_SHA1 | \
  					 DESC_HDR_MODE1_MDEU_HMAC)
  #define DESC_HDR_MODE1_MDEU_SHA224_HMAC	(DESC_HDR_MODE1_MDEU_SHA224 | \
  					 DESC_HDR_MODE1_MDEU_HMAC)
  #define DESC_HDR_MODE1_MDEUB_SHA384_HMAC	(DESC_HDR_MODE1_MDEUB_SHA384 | \
  						 DESC_HDR_MODE1_MDEU_HMAC)
  #define DESC_HDR_MODE1_MDEUB_SHA512_HMAC	(DESC_HDR_MODE1_MDEUB_SHA512 | \
  						 DESC_HDR_MODE1_MDEU_HMAC)
  
  /* direction of overall data flow (DIR) */
  #define	DESC_HDR_DIR_INBOUND		cpu_to_be32(0x00000002)
  
  /* request done notification (DN) */
  #define	DESC_HDR_DONE_NOTIFY		cpu_to_be32(0x00000001)
  
  /* descriptor types */
  #define DESC_HDR_TYPE_AESU_CTR_NONSNOOP		cpu_to_be32(0 << 3)
  #define DESC_HDR_TYPE_IPSEC_ESP			cpu_to_be32(1 << 3)
  #define DESC_HDR_TYPE_COMMON_NONSNOOP_NO_AFEU	cpu_to_be32(2 << 3)
  #define DESC_HDR_TYPE_HMAC_SNOOP_NO_AFEU	cpu_to_be32(4 << 3)
  
  /* link table extent field bits */
  #define DESC_PTR_LNKTBL_JUMP			0x80
  #define DESC_PTR_LNKTBL_RETURN			0x02
  #define DESC_PTR_LNKTBL_NEXT			0x01