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/*
* Copyright 2010 Tilera Corporation. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
*/
/**
* @file drv_xgbe_intf.h
* Interface to the hypervisor XGBE driver.
*/
#ifndef __DRV_XGBE_INTF_H__
#define __DRV_XGBE_INTF_H__
/**
* An object for forwarding VAs and PAs to the hypervisor.
* @ingroup types
*
* This allows the supervisor to specify a number of areas of memory to
* store packet buffers.
*/
typedef struct
{
/** The physical address of the memory. */
HV_PhysAddr pa;
/** Page table entry for the memory. This is only used to derive the
* memory's caching mode; the PA bits are ignored. */
HV_PTE pte;
/** The virtual address of the memory. */
HV_VirtAddr va;
/** Size (in bytes) of the memory area. */
int size;
}
netio_ipp_address_t;
/** The various pread/pwrite offsets into the hypervisor-level driver.
* @ingroup types
*/
typedef enum
{
/** Inform the Linux driver of the address of the NetIO arena memory.
* This offset is actually only used to convey information from netio
* to the Linux driver; it never makes it from there to the hypervisor.
* Write-only; takes a uint32_t specifying the VA address. */
NETIO_FIXED_ADDR = 0x5000000000000000ULL,
/** Inform the Linux driver of the size of the NetIO arena memory.
* This offset is actually only used to convey information from netio
* to the Linux driver; it never makes it from there to the hypervisor.
* Write-only; takes a uint32_t specifying the VA size. */
NETIO_FIXED_SIZE = 0x5100000000000000ULL,
/** Register current tile with IPP. Write then read: write, takes a
* netio_input_config_t, read returns a pointer to a netio_queue_impl_t. */
NETIO_IPP_INPUT_REGISTER_OFF = 0x6000000000000000ULL,
/** Unregister current tile from IPP. Write-only, takes a dummy argument. */
NETIO_IPP_INPUT_UNREGISTER_OFF = 0x6100000000000000ULL,
/** Start packets flowing. Write-only, takes a dummy argument. */
NETIO_IPP_INPUT_INIT_OFF = 0x6200000000000000ULL,
/** Stop packets flowing. Write-only, takes a dummy argument. */
NETIO_IPP_INPUT_UNINIT_OFF = 0x6300000000000000ULL,
/** Configure group (typically we group on VLAN). Write-only: takes an
* array of netio_group_t's, low 24 bits of the offset is the base group
* number times the size of a netio_group_t. */
NETIO_IPP_INPUT_GROUP_CFG_OFF = 0x6400000000000000ULL,
/** Configure bucket. Write-only: takes an array of netio_bucket_t's, low
* 24 bits of the offset is the base bucket number times the size of a
* netio_bucket_t. */
NETIO_IPP_INPUT_BUCKET_CFG_OFF = 0x6500000000000000ULL,
/** Get/set a parameter. Read or write: read or write data is the parameter
* value, low 32 bits of the offset is a __netio_getset_offset_t. */
NETIO_IPP_PARAM_OFF = 0x6600000000000000ULL,
/** Get fast I/O index. Read-only; returns a 4-byte base index value. */
NETIO_IPP_GET_FASTIO_OFF = 0x6700000000000000ULL,
/** Configure hijack IP address. Packets with this IPv4 dest address
* go to bucket NETIO_NUM_BUCKETS - 1. Write-only: takes an IP address
* in some standard form. FIXME: Define the form! */
NETIO_IPP_INPUT_HIJACK_CFG_OFF = 0x6800000000000000ULL,
/**
* Offsets beyond this point are reserved for the supervisor (although that
* enforcement must be done by the supervisor driver itself).
*/
NETIO_IPP_USER_MAX_OFF = 0x6FFFFFFFFFFFFFFFULL,
/** Register I/O memory. Write-only, takes a netio_ipp_address_t. */
NETIO_IPP_IOMEM_REGISTER_OFF = 0x7000000000000000ULL,
/** Unregister I/O memory. Write-only, takes a netio_ipp_address_t. */
NETIO_IPP_IOMEM_UNREGISTER_OFF = 0x7100000000000000ULL,
/* Offsets greater than 0x7FFFFFFF can't be used directly from Linux
* userspace code due to limitations in the pread/pwrite syscalls. */
/** Drain LIPP buffers. */
NETIO_IPP_DRAIN_OFF = 0xFA00000000000000ULL,
/** Supply a netio_ipp_address_t to be used as shared memory for the
* LEPP command queue. */
NETIO_EPP_SHM_OFF = 0xFB00000000000000ULL,
/* 0xFC... is currently unused. */
/** Stop IPP/EPP tiles. Write-only, takes a dummy argument. */
NETIO_IPP_STOP_SHIM_OFF = 0xFD00000000000000ULL,
/** Start IPP/EPP tiles. Write-only, takes a dummy argument. */
NETIO_IPP_START_SHIM_OFF = 0xFE00000000000000ULL,
/** Supply packet arena. Write-only, takes an array of
* netio_ipp_address_t values. */
NETIO_IPP_ADDRESS_OFF = 0xFF00000000000000ULL,
} netio_hv_offset_t;
/** Extract the base offset from an offset */
#define NETIO_BASE_OFFSET(off) ((off) & 0xFF00000000000000ULL)
/** Extract the local offset from an offset */
#define NETIO_LOCAL_OFFSET(off) ((off) & 0x00FFFFFFFFFFFFFFULL)
/**
* Get/set offset.
*/
typedef union
{
struct
{
uint64_t addr:48; /**< Class-specific address */
unsigned int class:8; /**< Class (e.g., NETIO_PARAM) */
unsigned int opcode:8; /**< High 8 bits of NETIO_IPP_PARAM_OFF */
}
bits; /**< Bitfields */
uint64_t word; /**< Aggregated value to use as the offset */
}
__netio_getset_offset_t;
/**
* Fast I/O index offsets (must be contiguous).
*/
typedef enum
{
NETIO_FASTIO_ALLOCATE = 0, /**< Get empty packet buffer */
NETIO_FASTIO_FREE_BUFFER = 1, /**< Give buffer back to IPP */
NETIO_FASTIO_RETURN_CREDITS = 2, /**< Give credits to IPP */
NETIO_FASTIO_SEND_PKT_NOCK = 3, /**< Send a packet, no checksum */
NETIO_FASTIO_SEND_PKT_CK = 4, /**< Send a packet, with checksum */
NETIO_FASTIO_SEND_PKT_VEC = 5, /**< Send a vector of packets */
NETIO_FASTIO_SENDV_PKT = 6, /**< Sendv one packet */
NETIO_FASTIO_NUM_INDEX = 7, /**< Total number of fast I/O indices */
} netio_fastio_index_t;
/** 3-word return type for Fast I/O call. */
typedef struct
{
int err; /**< Error code. */
uint32_t val0; /**< Value. Meaning depends upon the specific call. */
uint32_t val1; /**< Value. Meaning depends upon the specific call. */
} netio_fastio_rv3_t;
/** 0-argument fast I/O call */
int __netio_fastio0(uint32_t fastio_index);
/** 1-argument fast I/O call */
int __netio_fastio1(uint32_t fastio_index, uint32_t arg0);
/** 3-argument fast I/O call, 2-word return value */
netio_fastio_rv3_t __netio_fastio3_rv3(uint32_t fastio_index, uint32_t arg0,
uint32_t arg1, uint32_t arg2);
/** 4-argument fast I/O call */
int __netio_fastio4(uint32_t fastio_index, uint32_t arg0, uint32_t arg1,
uint32_t arg2, uint32_t arg3);
/** 6-argument fast I/O call */
int __netio_fastio6(uint32_t fastio_index, uint32_t arg0, uint32_t arg1,
uint32_t arg2, uint32_t arg3, uint32_t arg4, uint32_t arg5);
/** 9-argument fast I/O call */
int __netio_fastio9(uint32_t fastio_index, uint32_t arg0, uint32_t arg1,
uint32_t arg2, uint32_t arg3, uint32_t arg4, uint32_t arg5,
uint32_t arg6, uint32_t arg7, uint32_t arg8);
/** Allocate an empty packet.
* @param fastio_index Fast I/O index.
* @param size Size of the packet to allocate.
*/
#define __netio_fastio_allocate(fastio_index, size) \
__netio_fastio1((fastio_index) + NETIO_FASTIO_ALLOCATE, size)
/** Free a buffer.
* @param fastio_index Fast I/O index.
* @param handle Handle for the packet to free.
*/
#define __netio_fastio_free_buffer(fastio_index, handle) \
__netio_fastio1((fastio_index) + NETIO_FASTIO_FREE_BUFFER, handle)
/** Increment our receive credits.
* @param fastio_index Fast I/O index.
* @param credits Number of credits to add.
*/
#define __netio_fastio_return_credits(fastio_index, credits) \
__netio_fastio1((fastio_index) + NETIO_FASTIO_RETURN_CREDITS, credits)
/** Send packet, no checksum.
* @param fastio_index Fast I/O index.
* @param ackflag Nonzero if we want an ack.
* @param size Size of the packet.
* @param va Virtual address of start of packet.
* @param handle Packet handle.
*/
#define __netio_fastio_send_pkt_nock(fastio_index, ackflag, size, va, handle) \
__netio_fastio4((fastio_index) + NETIO_FASTIO_SEND_PKT_NOCK, ackflag, \
size, va, handle)
/** Send packet, calculate checksum.
* @param fastio_index Fast I/O index.
* @param ackflag Nonzero if we want an ack.
* @param size Size of the packet.
* @param va Virtual address of start of packet.
* @param handle Packet handle.
* @param csum0 Shim checksum header.
* @param csum1 Checksum seed.
*/
#define __netio_fastio_send_pkt_ck(fastio_index, ackflag, size, va, handle, \
csum0, csum1) \
__netio_fastio6((fastio_index) + NETIO_FASTIO_SEND_PKT_CK, ackflag, \
size, va, handle, csum0, csum1)
/** Format for the "csum0" argument to the __netio_fastio_send routines
* and LEPP. Note that this is currently exactly identical to the
* ShimProtocolOffloadHeader.
*/
typedef union
{
struct
{
unsigned int start_byte:7; /**< The first byte to be checksummed */
unsigned int count:14; /**< Number of bytes to be checksummed. */
unsigned int destination_byte:7; /**< The byte to write the checksum to. */
unsigned int reserved:4; /**< Reserved. */
} bits; /**< Decomposed method of access. */
unsigned int word; /**< To send out the IDN. */
} __netio_checksum_header_t;
/** Sendv packet with 1 or 2 segments.
* @param fastio_index Fast I/O index.
* @param flags Ack/csum/notify flags in low 3 bits; number of segments minus
* 1 in next 2 bits; expected checksum in high 16 bits.
* @param confno Confirmation number to request, if notify flag set.
* @param csum0 Checksum descriptor; if zero, no checksum.
* @param va_F Virtual address of first segment.
* @param va_L Virtual address of last segment, if 2 segments.
* @param len_F_L Length of first segment in low 16 bits; length of last
* segment, if 2 segments, in high 16 bits.
*/
#define __netio_fastio_sendv_pkt_1_2(fastio_index, flags, confno, csum0, \
va_F, va_L, len_F_L) \
__netio_fastio6((fastio_index) + NETIO_FASTIO_SENDV_PKT, flags, confno, \
csum0, va_F, va_L, len_F_L)
/** Send packet on PCIe interface.
* @param fastio_index Fast I/O index.
* @param flags Ack/csum/notify flags in low 3 bits.
* @param confno Confirmation number to request, if notify flag set.
* @param csum0 Checksum descriptor; Hard wired 0, not needed for PCIe.
* @param va_F Virtual address of the packet buffer.
* @param va_L Virtual address of last segment, if 2 segments. Hard wired 0.
* @param len_F_L Length of the packet buffer in low 16 bits.
*/
#define __netio_fastio_send_pcie_pkt(fastio_index, flags, confno, csum0, \
va_F, va_L, len_F_L) \
__netio_fastio6((fastio_index) + PCIE_FASTIO_SENDV_PKT, flags, confno, \
csum0, va_F, va_L, len_F_L)
/** Sendv packet with 3 or 4 segments.
* @param fastio_index Fast I/O index.
* @param flags Ack/csum/notify flags in low 3 bits; number of segments minus
* 1 in next 2 bits; expected checksum in high 16 bits.
* @param confno Confirmation number to request, if notify flag set.
* @param csum0 Checksum descriptor; if zero, no checksum.
* @param va_F Virtual address of first segment.
* @param va_L Virtual address of last segment (third segment if 3 segments,
* fourth segment if 4 segments).
* @param len_F_L Length of first segment in low 16 bits; length of last
* segment in high 16 bits.
* @param va_M0 Virtual address of "middle 0" segment; this segment is sent
* second when there are three segments, and third if there are four.
* @param va_M1 Virtual address of "middle 1" segment; this segment is sent
* second when there are four segments.
* @param len_M0_M1 Length of middle 0 segment in low 16 bits; length of middle
* 1 segment, if 4 segments, in high 16 bits.
*/
#define __netio_fastio_sendv_pkt_3_4(fastio_index, flags, confno, csum0, va_F, \
va_L, len_F_L, va_M0, va_M1, len_M0_M1) \
__netio_fastio9((fastio_index) + NETIO_FASTIO_SENDV_PKT, flags, confno, \
csum0, va_F, va_L, len_F_L, va_M0, va_M1, len_M0_M1)
/** Send vector of packets.
* @param fastio_index Fast I/O index.
* @param seqno Number of packets transmitted so far on this interface;
* used to decide which packets should be acknowledged.
* @param nentries Number of entries in vector.
* @param va Virtual address of start of vector entry array.
* @return 3-word netio_fastio_rv3_t structure. The structure's err member
* is an error code, or zero if no error. The val0 member is the
* updated value of seqno; it has been incremented by 1 for each
* packet sent. That increment may be less than nentries if an
* error occurred, or if some of the entries in the vector contain
* handles equal to NETIO_PKT_HANDLE_NONE. The val1 member is the
* updated value of nentries; it has been decremented by 1 for each
* vector entry processed. Again, that decrement may be less than
* nentries (leaving the returned value positive) if an error
* occurred.
*/
#define __netio_fastio_send_pkt_vec(fastio_index, seqno, nentries, va) \
__netio_fastio3_rv3((fastio_index) + NETIO_FASTIO_SEND_PKT_VEC, seqno, \
nentries, va)
/** An egress DMA command for LEPP. */
typedef struct
{
/** Is this a TSO transfer?
*
* NOTE: This field is always 0, to distinguish it from
* lepp_tso_cmd_t. It must come first!
*/
uint8_t tso : 1;
/** Unused padding bits. */
uint8_t _unused : 3;
/** Should this packet be sent directly from caches instead of DRAM,
* using hash-for-home to locate the packet data?
*/
uint8_t hash_for_home : 1;
/** Should we compute a checksum? */
uint8_t compute_checksum : 1;
/** Is this the final buffer for this packet?
*
* A single packet can be split over several input buffers (a "gather"
* operation). This flag indicates that this is the last buffer
* in a packet.
*/
uint8_t end_of_packet : 1;
/** Should LEPP advance 'comp_busy' when this DMA is fully finished? */
uint8_t send_completion : 1;
/** High bits of Client Physical Address of the start of the buffer
* to be egressed.
*
* NOTE: Only 6 bits are actually needed here, as CPAs are
* currently 38 bits. So two bits could be scavenged from this.
*/
uint8_t cpa_hi;
/** The number of bytes to be egressed. */
uint16_t length;
/** Low 32 bits of Client Physical Address of the start of the buffer
* to be egressed.
*/
uint32_t cpa_lo;
/** Checksum information (only used if 'compute_checksum'). */
__netio_checksum_header_t checksum_data;
} lepp_cmd_t;
/** A chunk of physical memory for a TSO egress. */
typedef struct
{
/** The low bits of the CPA. */
uint32_t cpa_lo;
/** The high bits of the CPA. */
uint16_t cpa_hi : 15;
/** Should this packet be sent directly from caches instead of DRAM,
* using hash-for-home to locate the packet data?
*/
uint16_t hash_for_home : 1;
/** The length in bytes. */
uint16_t length;
} lepp_frag_t;
/** An LEPP command that handles TSO. */
typedef struct
{
/** Is this a TSO transfer?
*
* NOTE: This field is always 1, to distinguish it from
* lepp_cmd_t. It must come first!
*/
uint8_t tso : 1;
/** Unused padding bits. */
uint8_t _unused : 7;
/** Size of the header[] array in bytes. It must be in the range
* [40, 127], which are the smallest header for a TCP packet over
* Ethernet and the maximum possible prepend size supported by
* hardware, respectively. Note that the array storage must be
* padded out to a multiple of four bytes so that the following
* LEPP command is aligned properly.
*/
uint8_t header_size;
/** Byte offset of the IP header in header[]. */
uint8_t ip_offset;
/** Byte offset of the TCP header in header[]. */
uint8_t tcp_offset;
/** The number of bytes to use for the payload of each packet,
* except of course the last one, which may not have enough bytes.
* This means that each Ethernet packet except the last will have a
* size of header_size + payload_size.
*/
uint16_t payload_size;
/** The length of the 'frags' array that follows this struct. */
uint16_t num_frags;
/** The actual frags. */
lepp_frag_t frags[0 /* Variable-sized; num_frags entries. */];
/*
* The packet header template logically follows frags[],
* but you can't declare that in C.
*
* uint32_t header[header_size_in_words_rounded_up];
*/
} lepp_tso_cmd_t;
/** An LEPP completion ring entry. */
typedef void* lepp_comp_t;
/** Maximum number of frags for one TSO command. This is adapted from
* linux's "MAX_SKB_FRAGS", and presumably over-estimates by one, for
* our page size of exactly 65536. We add one for a "body" fragment.
*/
#define LEPP_MAX_FRAGS (65536 / HV_DEFAULT_PAGE_SIZE_SMALL + 2 + 1)
/** Total number of bytes needed for an lepp_tso_cmd_t. */
#define LEPP_TSO_CMD_SIZE(num_frags, header_size) \
(sizeof(lepp_tso_cmd_t) + \
(num_frags) * sizeof(lepp_frag_t) + \
(((header_size) + 3) & -4))
/** The size of the lepp "cmd" queue. */
#define LEPP_CMD_QUEUE_BYTES \
(((CHIP_L2_CACHE_SIZE() - 2 * CHIP_L2_LINE_SIZE()) / \
(sizeof(lepp_cmd_t) + sizeof(lepp_comp_t))) * sizeof(lepp_cmd_t))
/** The largest possible command that can go in lepp_queue_t::cmds[]. */
#define LEPP_MAX_CMD_SIZE LEPP_TSO_CMD_SIZE(LEPP_MAX_FRAGS, 128)
/** The largest possible value of lepp_queue_t::cmd_{head, tail} (inclusive).
*/
#define LEPP_CMD_LIMIT \
(LEPP_CMD_QUEUE_BYTES - LEPP_MAX_CMD_SIZE)
/** The maximum number of completions in an LEPP queue. */
#define LEPP_COMP_QUEUE_SIZE \
((LEPP_CMD_LIMIT + sizeof(lepp_cmd_t) - 1) / sizeof(lepp_cmd_t))
/** Increment an index modulo the queue size. */
#define LEPP_QINC(var) \
(var = __insn_mnz(var - (LEPP_COMP_QUEUE_SIZE - 1), var + 1))
/** A queue used to convey egress commands from the client to LEPP. */
typedef struct
{
/** Index of first completion not yet processed by user code.
* If this is equal to comp_busy, there are no such completions.
*
* NOTE: This is only read/written by the user.
*/
unsigned int comp_head;
/** Index of first completion record not yet completed.
* If this is equal to comp_tail, there are no such completions.
* This index gets advanced (modulo LEPP_QUEUE_SIZE) whenever
* a command with the 'completion' bit set is finished.
*
* NOTE: This is only written by LEPP, only read by the user.
*/
volatile unsigned int comp_busy;
/** Index of the first empty slot in the completion ring.
* Entries from this up to but not including comp_head (in ring order)
* can be filled in with completion data.
*
* NOTE: This is only read/written by the user.
*/
unsigned int comp_tail;
/** Byte index of first command enqueued for LEPP but not yet processed.
*
* This is always divisible by sizeof(void*) and always <= LEPP_CMD_LIMIT.
*
* NOTE: LEPP advances this counter as soon as it no longer needs
* the cmds[] storage for this entry, but the transfer is not actually
* complete (i.e. the buffer pointed to by the command is no longer
* needed) until comp_busy advances.
*
* If this is equal to cmd_tail, the ring is empty.
*
* NOTE: This is only written by LEPP, only read by the user.
*/
volatile unsigned int cmd_head;
/** Byte index of first empty slot in the command ring. This field can
* be incremented up to but not equal to cmd_head (because that would
* mean the ring is empty).
*
* This is always divisible by sizeof(void*) and always <= LEPP_CMD_LIMIT.
*
* NOTE: This is read/written by the user, only read by LEPP.
*/
volatile unsigned int cmd_tail;
/** A ring of variable-sized egress DMA commands.
*
* NOTE: Only written by the user, only read by LEPP.
*/
char cmds[LEPP_CMD_QUEUE_BYTES]
__attribute__((aligned(CHIP_L2_LINE_SIZE())));
/** A ring of user completion data.
* NOTE: Only read/written by the user.
*/
lepp_comp_t comps[LEPP_COMP_QUEUE_SIZE]
__attribute__((aligned(CHIP_L2_LINE_SIZE())));
} lepp_queue_t;
/** An internal helper function for determining the number of entries
* available in a ring buffer, given that there is one sentinel.
*/
static inline unsigned int
_lepp_num_free_slots(unsigned int head, unsigned int tail)
{
/*
* One entry is reserved for use as a sentinel, to distinguish
* "empty" from "full". So we compute
* (head - tail - 1) % LEPP_QUEUE_SIZE, but without using a slow % operation.
*/
return (head - tail - 1) + ((head <= tail) ? LEPP_COMP_QUEUE_SIZE : 0);
}
/** Returns how many new comp entries can be enqueued. */
static inline unsigned int
lepp_num_free_comp_slots(const lepp_queue_t* q)
{
return _lepp_num_free_slots(q->comp_head, q->comp_tail);
}
static inline int
lepp_qsub(int v1, int v2)
{
int delta = v1 - v2;
return delta + ((delta >> 31) & LEPP_COMP_QUEUE_SIZE);
}
/** FIXME: Check this from linux, via a new "pwrite()" call. */
#define LIPP_VERSION 1
/** We use exactly two bytes of alignment padding. */
#define LIPP_PACKET_PADDING 2
/** The minimum size of a "small" buffer (including the padding). */
#define LIPP_SMALL_PACKET_SIZE 128
/*
* NOTE: The following two values should total to less than around
* 13582, to keep the total size used for "lipp_state_t" below 64K.
*/
/** The maximum number of "small" buffers.
* This is enough for 53 network cpus with 128 credits. Note that
* if these are exhausted, we will fall back to using large buffers.
*/
#define LIPP_SMALL_BUFFERS 6785
/** The maximum number of "large" buffers.
* This is enough for 53 network cpus with 128 credits.
*/
#define LIPP_LARGE_BUFFERS 6785
#endif /* __DRV_XGBE_INTF_H__ */
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