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/*
 * Copyright (C) ST-Ericsson SA 2010
 * Author: Shujuan Chen (shujuan.chen@stericsson.com)
 * Author: Joakim Bech (joakim.xx.bech@stericsson.com)
 * Author: Berne Hebark (berne.hebark@stericsson.com))
 * License terms: GNU General Public License (GPL) version 2
 */
#ifndef _HASH_ALG_H
#define _HASH_ALG_H

#include <linux/bitops.h>

#define HASH_BLOCK_SIZE			64
#define HASH_DMA_ALIGN_SIZE		4
#define HASH_DMA_PERFORMANCE_MIN_SIZE	1024
#define HASH_BYTES_PER_WORD		4

/* Maximum value of the length's high word */
#define HASH_HIGH_WORD_MAX_VAL		0xFFFFFFFFUL

/* Power on Reset values HASH registers */
#define HASH_RESET_CR_VALUE		0x0
#define HASH_RESET_STR_VALUE		0x0

/* Number of context swap registers */
#define HASH_CSR_COUNT			52

#define HASH_RESET_CSRX_REG_VALUE	0x0
#define HASH_RESET_CSFULL_REG_VALUE	0x0
#define HASH_RESET_CSDATAIN_REG_VALUE	0x0

#define HASH_RESET_INDEX_VAL		0x0
#define HASH_RESET_BIT_INDEX_VAL	0x0
#define HASH_RESET_BUFFER_VAL		0x0
#define HASH_RESET_LEN_HIGH_VAL		0x0
#define HASH_RESET_LEN_LOW_VAL		0x0

/* Control register bitfields */
#define HASH_CR_RESUME_MASK	0x11FCF

#define HASH_CR_SWITCHON_POS	31
#define HASH_CR_SWITCHON_MASK	BIT(31)

#define HASH_CR_EMPTYMSG_POS	20
#define HASH_CR_EMPTYMSG_MASK	BIT(20)

#define HASH_CR_DINF_POS	12
#define HASH_CR_DINF_MASK	BIT(12)

#define HASH_CR_NBW_POS		8
#define HASH_CR_NBW_MASK	0x00000F00UL

#define HASH_CR_LKEY_POS	16
#define HASH_CR_LKEY_MASK	BIT(16)

#define HASH_CR_ALGO_POS	7
#define HASH_CR_ALGO_MASK	BIT(7)

#define HASH_CR_MODE_POS	6
#define HASH_CR_MODE_MASK	BIT(6)

#define HASH_CR_DATAFORM_POS	4
#define HASH_CR_DATAFORM_MASK	(BIT(4) | BIT(5))

#define HASH_CR_DMAE_POS	3
#define HASH_CR_DMAE_MASK	BIT(3)

#define HASH_CR_INIT_POS	2
#define HASH_CR_INIT_MASK	BIT(2)

#define HASH_CR_PRIVN_POS	1
#define HASH_CR_PRIVN_MASK	BIT(1)

#define HASH_CR_SECN_POS	0
#define HASH_CR_SECN_MASK	BIT(0)

/* Start register bitfields */
#define HASH_STR_DCAL_POS	8
#define HASH_STR_DCAL_MASK	BIT(8)
#define HASH_STR_DEFAULT	0x0

#define HASH_STR_NBLW_POS	0
#define HASH_STR_NBLW_MASK	0x0000001FUL

#define HASH_NBLW_MAX_VAL	0x1F

/* PrimeCell IDs */
#define HASH_P_ID0		0xE0
#define HASH_P_ID1		0x05
#define HASH_P_ID2		0x38
#define HASH_P_ID3		0x00
#define HASH_CELL_ID0		0x0D
#define HASH_CELL_ID1		0xF0
#define HASH_CELL_ID2		0x05
#define HASH_CELL_ID3		0xB1

#define HASH_SET_BITS(reg_name, mask)	\
	writel_relaxed((readl_relaxed(reg_name) | mask), reg_name)

#define HASH_CLEAR_BITS(reg_name, mask)	\
	writel_relaxed((readl_relaxed(reg_name) & ~mask), reg_name)

#define HASH_PUT_BITS(reg, val, shift, mask)	\
	writel_relaxed(((readl(reg) & ~(mask)) |	\
		(((u32)val << shift) & (mask))), reg)

#define HASH_SET_DIN(val, len)	writesl(&device_data->base->din, (val), (len))

#define HASH_INITIALIZE			\
	HASH_PUT_BITS(			\
		&device_data->base->cr,	\
		0x01, HASH_CR_INIT_POS,	\
		HASH_CR_INIT_MASK)

#define HASH_SET_DATA_FORMAT(data_format)				\
		HASH_PUT_BITS(						\
			&device_data->base->cr,				\
			(u32) (data_format), HASH_CR_DATAFORM_POS,	\
			HASH_CR_DATAFORM_MASK)
#define HASH_SET_NBLW(val)					\
		HASH_PUT_BITS(					\
			&device_data->base->str,		\
			(u32) (val), HASH_STR_NBLW_POS,		\
			HASH_STR_NBLW_MASK)
#define HASH_SET_DCAL					\
		HASH_PUT_BITS(				\
			&device_data->base->str,	\
			0x01, HASH_STR_DCAL_POS,	\
			HASH_STR_DCAL_MASK)

/* Hardware access method */
enum hash_mode {
	HASH_MODE_CPU,
	HASH_MODE_DMA
};

/**
 * struct uint64 - Structure to handle 64 bits integers.
 * @high_word:	Most significant bits.
 * @low_word:	Least significant bits.
 *
 * Used to handle 64 bits integers.
 */
struct uint64 {
	u32 high_word;
	u32 low_word;
};

/**
 * struct hash_register - Contains all registers in ux500 hash hardware.
 * @cr:		HASH control register (0x000).
 * @din:	HASH data input register (0x004).
 * @str:	HASH start register (0x008).
 * @hx:		HASH digest register 0..7 (0x00c-0x01C).
 * @padding0:	Reserved (0x02C).
 * @itcr:	Integration test control register (0x080).
 * @itip:	Integration test input register (0x084).
 * @itop:	Integration test output register (0x088).
 * @padding1:	Reserved (0x08C).
 * @csfull:	HASH context full register (0x0F8).
 * @csdatain:	HASH context swap data input register (0x0FC).
 * @csrx:	HASH context swap register 0..51 (0x100-0x1CC).
 * @padding2:	Reserved (0x1D0).
 * @periphid0:	HASH peripheral identification register 0 (0xFE0).
 * @periphid1:	HASH peripheral identification register 1 (0xFE4).
 * @periphid2:	HASH peripheral identification register 2 (0xFE8).
 * @periphid3:	HASH peripheral identification register 3 (0xFEC).
 * @cellid0:	HASH PCell identification register 0 (0xFF0).
 * @cellid1:	HASH PCell identification register 1 (0xFF4).
 * @cellid2:	HASH PCell identification register 2 (0xFF8).
 * @cellid3:	HASH PCell identification register 3 (0xFFC).
 *
 * The device communicates to the HASH via 32-bit-wide control registers
 * accessible via the 32-bit width AMBA rev. 2.0 AHB Bus. Below is a structure
 * with the registers used.
 */
struct hash_register {
	u32 cr;
	u32 din;
	u32 str;
	u32 hx[8];

	u32 padding0[(0x080 - 0x02C) / sizeof(u32)];

	u32 itcr;
	u32 itip;
	u32 itop;

	u32 padding1[(0x0F8 - 0x08C) / sizeof(u32)];

	u32 csfull;
	u32 csdatain;
	u32 csrx[HASH_CSR_COUNT];

	u32 padding2[(0xFE0 - 0x1D0) / sizeof(u32)];

	u32 periphid0;
	u32 periphid1;
	u32 periphid2;
	u32 periphid3;

	u32 cellid0;
	u32 cellid1;
	u32 cellid2;
	u32 cellid3;
};

/**
 * struct hash_state - Hash context state.
 * @temp_cr:	Temporary HASH Control Register.
 * @str_reg:	HASH Start Register.
 * @din_reg:	HASH Data Input Register.
 * @csr[52]:	HASH Context Swap Registers 0-39.
 * @csfull:	HASH Context Swap Registers 40 ie Status flags.
 * @csdatain:	HASH Context Swap Registers 41 ie Input data.
 * @buffer:	Working buffer for messages going to the hardware.
 * @length:	Length of the part of message hashed so far (floor(N/64) * 64).
 * @index:	Valid number of bytes in buffer (N % 64).
 * @bit_index:	Valid number of bits in buffer (N % 8).
 *
 * This structure is used between context switches, i.e. when ongoing jobs are
 * interupted with new jobs. When this happens we need to store intermediate
 * results in software.
 *
 * WARNING: "index" is the  member of the structure, to be sure  that "buffer"
 * is aligned on a 4-bytes boundary. This is highly implementation dependent
 * and MUST be checked whenever this code is ported on new platforms.
 */
struct hash_state {
	u32		temp_cr;
	u32		str_reg;
	u32		din_reg;
	u32		csr[52];
	u32		csfull;
	u32		csdatain;
	u32		buffer[HASH_BLOCK_SIZE / sizeof(u32)];
	struct uint64	length;
	u8		index;
	u8		bit_index;
};

/**
 * enum hash_device_id - HASH device ID.
 * @HASH_DEVICE_ID_0: Hash hardware with ID 0
 * @HASH_DEVICE_ID_1: Hash hardware with ID 1
 */
enum hash_device_id {
	HASH_DEVICE_ID_0 = 0,
	HASH_DEVICE_ID_1 = 1
};

/**
 * enum hash_data_format - HASH data format.
 * @HASH_DATA_32_BITS:	32 bits data format
 * @HASH_DATA_16_BITS:	16 bits data format
 * @HASH_DATA_8_BITS:	8 bits data format.
 * @HASH_DATA_1_BITS:	1 bit data format.
 */
enum hash_data_format {
	HASH_DATA_32_BITS	= 0x0,
	HASH_DATA_16_BITS	= 0x1,
	HASH_DATA_8_BITS	= 0x2,
	HASH_DATA_1_BIT		= 0x3
};

/**
 * enum hash_algo - Enumeration for selecting between SHA1 or SHA2 algorithm.
 * @HASH_ALGO_SHA1: Indicates that SHA1 is used.
 * @HASH_ALGO_SHA2: Indicates that SHA2 (SHA256) is used.
 */
enum hash_algo {
	HASH_ALGO_SHA1		= 0x0,
	HASH_ALGO_SHA256	= 0x1
};

/**
 * enum hash_op - Enumeration for selecting between HASH or HMAC mode.
 * @HASH_OPER_MODE_HASH: Indicates usage of normal HASH mode.
 * @HASH_OPER_MODE_HMAC: Indicates usage of HMAC.
 */
enum hash_op {
	HASH_OPER_MODE_HASH = 0x0,
	HASH_OPER_MODE_HMAC = 0x1
};

/**
 * struct hash_config - Configuration data for the hardware.
 * @data_format:	Format of data entered into the hash data in register.
 * @algorithm:		Algorithm selection bit.
 * @oper_mode:		Operating mode selection bit.
 */
struct hash_config {
	int data_format;
	int algorithm;
	int oper_mode;
};

/**
 * struct hash_dma - Structure used for dma.
 * @mask:		DMA capabilities bitmap mask.
 * @complete:		Used to maintain state for a "completion".
 * @chan_mem2hash:	DMA channel.
 * @cfg_mem2hash:	DMA channel configuration.
 * @sg_len:		Scatterlist length.
 * @sg:			Scatterlist.
 * @nents:		Number of sg entries.
 */
struct hash_dma {
	dma_cap_mask_t		mask;
	struct completion	complete;
	struct dma_chan		*chan_mem2hash;
	void			*cfg_mem2hash;
	int			sg_len;
	struct scatterlist	*sg;
	int			nents;
};

/**
 * struct hash_ctx - The context used for hash calculations.
 * @key:	The key used in the operation.
 * @keylen:	The length of the key.
 * @state:	The state of the current calculations.
 * @config:	The current configuration.
 * @digestsize:	The size of current digest.
 * @device:	Pointer to the device structure.
 */
struct hash_ctx {
	u8			*key;
	u32			keylen;
	struct hash_config	config;
	int			digestsize;
	struct hash_device_data	*device;
};

/**
 * struct hash_ctx - The request context used for hash calculations.
 * @state:	The state of the current calculations.
 * @dma_mode:	Used in special cases (workaround), e.g. need to change to
 *		cpu mode, if not supported/working in dma mode.
 * @updated:	Indicates if hardware is initialized for new operations.
 */
struct hash_req_ctx {
	struct hash_state	state;
	bool			dma_mode;
	u8			updated;
};

/**
 * struct hash_device_data - structure for a hash device.
 * @base:		Pointer to the hardware base address.
 * @list_node:		For inclusion in klist.
 * @dev:		Pointer to the device dev structure.
 * @ctx_lock:		Spinlock for current_ctx.
 * @current_ctx:	Pointer to the currently allocated context.
 * @power_state:	TRUE = power state on, FALSE = power state off.
 * @power_state_lock:	Spinlock for power_state.
 * @regulator:		Pointer to the device's power control.
 * @clk:		Pointer to the device's clock control.
 * @restore_dev_state:	TRUE = saved state, FALSE = no saved state.
 * @dma:		Structure used for dma.
 */
struct hash_device_data {
	struct hash_register __iomem	*base;
	struct klist_node	list_node;
	struct device		*dev;
	struct spinlock		ctx_lock;
	struct hash_ctx		*current_ctx;
	bool			power_state;
	struct spinlock		power_state_lock;
	struct regulator	*regulator;
	struct clk		*clk;
	bool			restore_dev_state;
	struct hash_state	state; /* Used for saving and resuming state */
	struct hash_dma		dma;
};

int hash_check_hw(struct hash_device_data *device_data);

int hash_setconfiguration(struct hash_device_data *device_data,
		struct hash_config *config);

void hash_begin(struct hash_device_data *device_data, struct hash_ctx *ctx);

void hash_get_digest(struct hash_device_data *device_data,
		u8 *digest, int algorithm);

int hash_hw_update(struct ahash_request *req);

int hash_save_state(struct hash_device_data *device_data,
		struct hash_state *state);

int hash_resume_state(struct hash_device_data *device_data,
		const struct hash_state *state);

#endif