/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
/* Copyright (C) 2015-2018 Netronome Systems, Inc. */

/*
 * nfp_cpp.h
 * Interface for low-level NFP CPP access.
 * Authors: Jason McMullan <jason.mcmullan@netronome.com>
 *          Rolf Neugebauer <rolf.neugebauer@netronome.com>
 */
#ifndef __NFP_CPP_H__
#define __NFP_CPP_H__

#include <linux/ctype.h>
#include <linux/types.h>
#include <linux/sizes.h>

#ifndef NFP_SUBSYS
#define NFP_SUBSYS "nfp"
#endif

#define nfp_err(cpp, fmt, args...) \
        dev_err(nfp_cpp_device(cpp)->parent, NFP_SUBSYS ": " fmt, ## args)
#define nfp_warn(cpp, fmt, args...) \
        dev_warn(nfp_cpp_device(cpp)->parent, NFP_SUBSYS ": " fmt, ## args)
#define nfp_info(cpp, fmt, args...) \
        dev_info(nfp_cpp_device(cpp)->parent, NFP_SUBSYS ": " fmt, ## args)
#define nfp_dbg(cpp, fmt, args...) \
        dev_dbg(nfp_cpp_device(cpp)->parent, NFP_SUBSYS ": " fmt, ## args)
#define nfp_printk(level, cpp, fmt, args...) \
        dev_printk(level, nfp_cpp_device(cpp)->parent,  \
                   NFP_SUBSYS ": " fmt, ## args)

#define PCI_64BIT_BAR_COUNT             3

#define NFP_CPP_NUM_TARGETS             16
/* Max size of area it should be safe to request */
#define NFP_CPP_SAFE_AREA_SIZE          SZ_2M

/* NFP_MUTEX_WAIT_* are timeouts in seconds when waiting for a mutex */
#define NFP_MUTEX_WAIT_FIRST_WARN       15
#define NFP_MUTEX_WAIT_NEXT_WARN        5
#define NFP_MUTEX_WAIT_ERROR            60

struct device;

struct nfp_cpp_area;
struct nfp_cpp;
struct resource;

/* Wildcard indicating a CPP read or write action
 *
 * The action used will be either read or write depending on whether a
 * read or write instruction/call is performed on the NFP_CPP_ID.  It
 * is recomended that the RW action is used even if all actions to be
 * performed on a NFP_CPP_ID are known to be only reads or writes.
 * Doing so will in many cases save NFP CPP internal software
 * resources.
 */
#define NFP_CPP_ACTION_RW               32

#define NFP_CPP_TARGET_ID_MASK          0x1f

#define NFP_CPP_ATOMIC_RD(target, island) \
        NFP_CPP_ISLAND_ID((target), 3, 0, (island))
#define NFP_CPP_ATOMIC_WR(target, island) \
        NFP_CPP_ISLAND_ID((target), 4, 0, (island))

/**
 * NFP_CPP_ID() - pack target, token, and action into a CPP ID.
 * @target:     NFP CPP target id
 * @action:     NFP CPP action id
 * @token:      NFP CPP token id
 *
 * Create a 32-bit CPP identifier representing the access to be made.
 * These identifiers are used as parameters to other NFP CPP
 * functions.  Some CPP devices may allow wildcard identifiers to be
 * specified.
 *
 * Return:      NFP CPP ID
 */
#define NFP_CPP_ID(target, action, token)                        \
        ((((target) & 0x7f) << 24) | (((token)  & 0xff) << 16) | \
         (((action) & 0xff) <<  8))

/**
 * NFP_CPP_ISLAND_ID() - pack target, token, action, and island into a CPP ID.
 * @target:     NFP CPP target id
 * @action:     NFP CPP action id
 * @token:      NFP CPP token id
 * @island:     NFP CPP island id
 *
 * Create a 32-bit CPP identifier representing the access to be made.
 * These identifiers are used as parameters to other NFP CPP
 * functions.  Some CPP devices may allow wildcard identifiers to be
 * specified.
 *
 * Return:      NFP CPP ID
 */
#define NFP_CPP_ISLAND_ID(target, action, token, island)         \
        ((((target) & 0x7f) << 24) | (((token)  & 0xff) << 16) | \
         (((action) & 0xff) <<  8) | (((island) & 0xff) << 0))

/**
 * NFP_CPP_ID_TARGET_of() - Return the NFP CPP target of a NFP CPP ID
 * @id:         NFP CPP ID
 *
 * Return:      NFP CPP target
 */
static inline u8 NFP_CPP_ID_TARGET_of(u32 id)
{
        return (id >> 24) & NFP_CPP_TARGET_ID_MASK;
}

/**
 * NFP_CPP_ID_TOKEN_of() - Return the NFP CPP token of a NFP CPP ID
 * @id:         NFP CPP ID
 * Return:      NFP CPP token
 */
static inline u8 NFP_CPP_ID_TOKEN_of(u32 id)
{
        return (id >> 16) & 0xff;
}

/**
 * NFP_CPP_ID_ACTION_of() - Return the NFP CPP action of a NFP CPP ID
 * @id:         NFP CPP ID
 *
 * Return:      NFP CPP action
 */
static inline u8 NFP_CPP_ID_ACTION_of(u32 id)
{
        return (id >> 8) & 0xff;
}

/**
 * NFP_CPP_ID_ISLAND_of() - Return the NFP CPP island of a NFP CPP ID
 * @id: NFP CPP ID
 *
 * Return:      NFP CPP island
 */
static inline u8 NFP_CPP_ID_ISLAND_of(u32 id)
{
        return (id >> 0) & 0xff;
}

/* NFP Interface types - logical interface for this CPP connection
 * 4 bits are reserved for interface type.
 */
#define NFP_CPP_INTERFACE_TYPE_INVALID      0x0
#define NFP_CPP_INTERFACE_TYPE_PCI          0x1
#define NFP_CPP_INTERFACE_TYPE_ARM          0x2
#define NFP_CPP_INTERFACE_TYPE_RPC          0x3
#define NFP_CPP_INTERFACE_TYPE_ILA          0x4

/**
 * NFP_CPP_INTERFACE() - Construct a 16-bit NFP Interface ID
 * @type:       NFP Interface Type
 * @unit:       Unit identifier for the interface type
 * @channel:    Channel identifier for the interface unit
 *
 * Interface IDs consists of 4 bits of interface type,
 * 4 bits of unit identifier, and 8 bits of channel identifier.
 *
 * The NFP Interface ID is used in the implementation of
 * NFP CPP API mutexes, which use the MU Atomic CompareAndWrite
 * operation - hence the limit to 16 bits to be able to
 * use the NFP Interface ID as a lock owner.
 *
 * Return:      Interface ID
 */
#define NFP_CPP_INTERFACE(type, unit, channel)  \
        ((((type) & 0xf) << 12) |               \
         (((unit) & 0xf) <<  8) |               \
         (((channel) & 0xff) << 0))

/**
 * NFP_CPP_INTERFACE_TYPE_of() - Get the interface type
 * @interface:  NFP Interface ID
 * Return:      NFP Interface ID's type
 */
#define NFP_CPP_INTERFACE_TYPE_of(interface)   (((interface) >> 12) & 0xf)

/**
 * NFP_CPP_INTERFACE_UNIT_of() - Get the interface unit
 * @interface:  NFP Interface ID
 * Return:      NFP Interface ID's unit
 */
#define NFP_CPP_INTERFACE_UNIT_of(interface)   (((interface) >>  8) & 0xf)

/**
 * NFP_CPP_INTERFACE_CHANNEL_of() - Get the interface channel
 * @interface:  NFP Interface ID
 * Return:      NFP Interface ID's channel
 */
#define NFP_CPP_INTERFACE_CHANNEL_of(interface)   (((interface) >>  0) & 0xff)

/* Implemented in nfp_cppcore.c */
void nfp_cpp_free(struct nfp_cpp *cpp);
u32 nfp_cpp_model(struct nfp_cpp *cpp);
u16 nfp_cpp_interface(struct nfp_cpp *cpp);
int nfp_cpp_serial(struct nfp_cpp *cpp, const u8 **serial);
unsigned int nfp_cpp_mu_locality_lsb(struct nfp_cpp *cpp);

struct nfp_cpp_area *nfp_cpp_area_alloc_with_name(struct nfp_cpp *cpp,
                                                  u32 cpp_id,
                                                  const char *name,
                                                  unsigned long long address,
                                                  unsigned long size);
struct nfp_cpp_area *nfp_cpp_area_alloc(struct nfp_cpp *cpp, u32 cpp_id,
                                        unsigned long long address,
                                        unsigned long size);
struct nfp_cpp_area *
nfp_cpp_area_alloc_acquire(struct nfp_cpp *cpp, const char *name, u32 cpp_id,
                           unsigned long long address, unsigned long size);
void nfp_cpp_area_free(struct nfp_cpp_area *area);
int nfp_cpp_area_acquire(struct nfp_cpp_area *area);
int nfp_cpp_area_acquire_nonblocking(struct nfp_cpp_area *area);
void nfp_cpp_area_release(struct nfp_cpp_area *area);
void nfp_cpp_area_release_free(struct nfp_cpp_area *area);
int nfp_cpp_area_read(struct nfp_cpp_area *area, unsigned long offset,
                      void *buffer, size_t length);
int nfp_cpp_area_write(struct nfp_cpp_area *area, unsigned long offset,
                       const void *buffer, size_t length);
size_t nfp_cpp_area_size(struct nfp_cpp_area *area);
const char *nfp_cpp_area_name(struct nfp_cpp_area *cpp_area);
void *nfp_cpp_area_priv(struct nfp_cpp_area *cpp_area);
struct nfp_cpp *nfp_cpp_area_cpp(struct nfp_cpp_area *cpp_area);
struct resource *nfp_cpp_area_resource(struct nfp_cpp_area *area);
phys_addr_t nfp_cpp_area_phys(struct nfp_cpp_area *area);
void __iomem *nfp_cpp_area_iomem(struct nfp_cpp_area *area);

int nfp_cpp_area_readl(struct nfp_cpp_area *area, unsigned long offset,
                       u32 *value);
int nfp_cpp_area_writel(struct nfp_cpp_area *area, unsigned long offset,
                        u32 value);
int nfp_cpp_area_readq(struct nfp_cpp_area *area, unsigned long offset,
                       u64 *value);
int nfp_cpp_area_writeq(struct nfp_cpp_area *area, unsigned long offset,
                        u64 value);
int nfp_cpp_area_fill(struct nfp_cpp_area *area, unsigned long offset,
                      u32 value, size_t length);

int nfp_xpb_readl(struct nfp_cpp *cpp, u32 xpb_tgt, u32 *value);
int nfp_xpb_writel(struct nfp_cpp *cpp, u32 xpb_tgt, u32 value);
int nfp_xpb_writelm(struct nfp_cpp *cpp, u32 xpb_tgt, u32 mask, u32 value);

/* Implemented in nfp_cpplib.c */
int nfp_cpp_read(struct nfp_cpp *cpp, u32 cpp_id,
                 unsigned long long address, void *kernel_vaddr, size_t length);
int nfp_cpp_write(struct nfp_cpp *cpp, u32 cpp_id,
                  unsigned long long address, const void *kernel_vaddr,
                  size_t length);
int nfp_cpp_readl(struct nfp_cpp *cpp, u32 cpp_id,
                  unsigned long long address, u32 *value);
int nfp_cpp_writel(struct nfp_cpp *cpp, u32 cpp_id,
                   unsigned long long address, u32 value);
int nfp_cpp_readq(struct nfp_cpp *cpp, u32 cpp_id,
                  unsigned long long address, u64 *value);
int nfp_cpp_writeq(struct nfp_cpp *cpp, u32 cpp_id,
                   unsigned long long address, u64 value);

u8 __iomem *
nfp_cpp_map_area(struct nfp_cpp *cpp, const char *name, u32 cpp_id, u64 addr,
                 unsigned long size, struct nfp_cpp_area **area);

struct nfp_cpp_mutex;

int nfp_cpp_mutex_init(struct nfp_cpp *cpp, int target,
                       unsigned long long address, u32 key_id);
struct nfp_cpp_mutex *nfp_cpp_mutex_alloc(struct nfp_cpp *cpp, int target,
                                          unsigned long long address,
                                          u32 key_id);
void nfp_cpp_mutex_free(struct nfp_cpp_mutex *mutex);
int nfp_cpp_mutex_lock(struct nfp_cpp_mutex *mutex);
int nfp_cpp_mutex_unlock(struct nfp_cpp_mutex *mutex);
int nfp_cpp_mutex_trylock(struct nfp_cpp_mutex *mutex);
int nfp_cpp_mutex_reclaim(struct nfp_cpp *cpp, int target,
                          unsigned long long address);

/**
 * nfp_cppcore_pcie_unit() - Get PCI Unit of a CPP handle
 * @cpp:        CPP handle
 *
 * Return: PCI unit for the NFP CPP handle
 */
static inline u8 nfp_cppcore_pcie_unit(struct nfp_cpp *cpp)
{
        return NFP_CPP_INTERFACE_UNIT_of(nfp_cpp_interface(cpp));
}

struct nfp_cpp_explicit;

struct nfp_cpp_explicit_command {
        u32 cpp_id;
        u16 data_ref;
        u8  data_master;
        u8  len;
        u8  byte_mask;
        u8  signal_master;
        u8  signal_ref;
        u8  posted;
        u8  siga;
        u8  sigb;
        s8   siga_mode;
        s8   sigb_mode;
};

#define NFP_SERIAL_LEN          6

/**
 * struct nfp_cpp_operations - NFP CPP operations structure
 * @area_priv_size:     Size of the nfp_cpp_area private data
 * @owner:              Owner module
 * @init:               Initialize the NFP CPP bus
 * @free:               Free the bus
 * @read_serial:        Read serial number to memory provided
 * @get_interface:      Return CPP interface
 * @area_init:          Initialize a new NFP CPP area (not serialized)
 * @area_cleanup:       Clean up a NFP CPP area (not serialized)
 * @area_acquire:       Acquire the NFP CPP area (serialized)
 * @area_release:       Release area (serialized)
 * @area_resource:      Get resource range of area (not serialized)
 * @area_phys:          Get physical address of area (not serialized)
 * @area_iomem:         Get iomem of area (not serialized)
 * @area_read:          Perform a read from a NFP CPP area (serialized)
 * @area_write:         Perform a write to a NFP CPP area (serialized)
 * @explicit_priv_size: Size of an explicit's private area
 * @explicit_acquire:   Acquire an explicit area
 * @explicit_release:   Release an explicit area
 * @explicit_put:       Write data to send
 * @explicit_get:       Read data received
 * @explicit_do:        Perform the transaction
 */
struct nfp_cpp_operations {
        size_t area_priv_size;
        struct module *owner;

        int (*init)(struct nfp_cpp *cpp);
        void (*free)(struct nfp_cpp *cpp);

        int (*read_serial)(struct device *dev, u8 *serial);
        int (*get_interface)(struct device *dev);

        int (*area_init)(struct nfp_cpp_area *area,
                         u32 dest, unsigned long long address,
                         unsigned long size);
        void (*area_cleanup)(struct nfp_cpp_area *area);
        int (*area_acquire)(struct nfp_cpp_area *area);
        void (*area_release)(struct nfp_cpp_area *area);
        struct resource *(*area_resource)(struct nfp_cpp_area *area);
        phys_addr_t (*area_phys)(struct nfp_cpp_area *area);
        void __iomem *(*area_iomem)(struct nfp_cpp_area *area);
        int (*area_read)(struct nfp_cpp_area *area, void *kernel_vaddr,
                         unsigned long offset, unsigned int length);
        int (*area_write)(struct nfp_cpp_area *area, const void *kernel_vaddr,
                          unsigned long offset, unsigned int length);

        size_t explicit_priv_size;
        int (*explicit_acquire)(struct nfp_cpp_explicit *expl);
        void (*explicit_release)(struct nfp_cpp_explicit *expl);
        int (*explicit_put)(struct nfp_cpp_explicit *expl,
                            const void *buff, size_t len);
        int (*explicit_get)(struct nfp_cpp_explicit *expl,
                            void *buff, size_t len);
        int (*explicit_do)(struct nfp_cpp_explicit *expl,
                           const struct nfp_cpp_explicit_command *cmd,
                           u64 address);
};

struct nfp_cpp *
nfp_cpp_from_operations(const struct nfp_cpp_operations *ops,
                        struct device *parent, void *priv);
void *nfp_cpp_priv(struct nfp_cpp *priv);

int nfp_cpp_area_cache_add(struct nfp_cpp *cpp, size_t size);

/* The following section contains extensions to the
 * NFP CPP API, to be used in a Linux kernel-space context.
 */

/* Use this channel ID for multiple virtual channel interfaces
 * (ie ARM and PCIe) when setting up the interface field.
 */
#define NFP_CPP_INTERFACE_CHANNEL_PEROPENER     255
struct device *nfp_cpp_device(struct nfp_cpp *cpp);

/* Return code masks for nfp_cpp_explicit_do()
 */
#define NFP_SIGNAL_MASK_A       BIT(0)  /* Signal A fired */
#define NFP_SIGNAL_MASK_B       BIT(1)  /* Signal B fired */

enum nfp_cpp_explicit_signal_mode {
        NFP_SIGNAL_NONE = 0,
        NFP_SIGNAL_PUSH = 1,
        NFP_SIGNAL_PUSH_OPTIONAL = -1,
        NFP_SIGNAL_PULL = 2,
        NFP_SIGNAL_PULL_OPTIONAL = -2,
};

struct nfp_cpp_explicit *nfp_cpp_explicit_acquire(struct nfp_cpp *cpp);
int nfp_cpp_explicit_set_target(struct nfp_cpp_explicit *expl, u32 cpp_id,
                                u8 len, u8 mask);
int nfp_cpp_explicit_set_data(struct nfp_cpp_explicit *expl,
                              u8 data_master, u16 data_ref);
int nfp_cpp_explicit_set_signal(struct nfp_cpp_explicit *expl,
                                u8 signal_master, u8 signal_ref);
int nfp_cpp_explicit_set_posted(struct nfp_cpp_explicit *expl, int posted,
                                u8 siga,
                                enum nfp_cpp_explicit_signal_mode siga_mode,
                                u8 sigb,
                                enum nfp_cpp_explicit_signal_mode sigb_mode);
int nfp_cpp_explicit_put(struct nfp_cpp_explicit *expl,
                         const void *buff, size_t len);
int nfp_cpp_explicit_do(struct nfp_cpp_explicit *expl, u64 address);
int nfp_cpp_explicit_get(struct nfp_cpp_explicit *expl, void *buff, size_t len);
void nfp_cpp_explicit_release(struct nfp_cpp_explicit *expl);
struct nfp_cpp *nfp_cpp_explicit_cpp(struct nfp_cpp_explicit *expl);
void *nfp_cpp_explicit_priv(struct nfp_cpp_explicit *cpp_explicit);

/* Implemented in nfp_cpplib.c */

int nfp_cpp_model_autodetect(struct nfp_cpp *cpp, u32 *model);

int nfp_cpp_explicit_read(struct nfp_cpp *cpp, u32 cpp_id,
                          u64 addr, void *buff, size_t len,
                          int width_read);

int nfp_cpp_explicit_write(struct nfp_cpp *cpp, u32 cpp_id,
                           u64 addr, const void *buff, size_t len,
                           int width_write);

#endif /* !__NFP_CPP_H__ */