linux-imx

/* SPDX-License-Identifier: GPL-2.0 */

/*

 * Thunderbolt driver - NHI registers

 *

 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>

 * Copyright (C) 2018, Intel Corporation

 */

​

#ifndef NHI_REGS_H_

#define NHI_REGS_H_

​

#include <linux/types.h>

​

enum ring_flags {

    RING_FLAG_ISOCH_ENABLE = 1 << 27, /* TX only? */

    RING_FLAG_E2E_FLOW_CONTROL = 1 << 28,

    RING_FLAG_PCI_NO_SNOOP = 1 << 29,

    RING_FLAG_RAW = 1 << 30, /* ignore EOF/SOF mask, include checksum */

    RING_FLAG_ENABLE = 1 << 31,

};

​

/**

 * struct ring_desc - TX/RX ring entry

 *

 * For TX set length/eof/sof.

 * For RX length/eof/sof are set by the NHI.

 */

struct ring_desc {

    u64 phys;

    u32 length:12;

    u32 eof:4;

    u32 sof:4;

    enum ring_desc_flags flags:12;

    u32 time; /* write zero */

} __packed;

​

/* NHI registers in bar 0 */

​

/*

 * 16 bytes per entry, one entry for every hop (REG_HOP_COUNT)

 * 00: physical pointer to an array of struct ring_desc

 * 08: ring tail (set by NHI)

 * 10: ring head (index of first non posted descriptor)

 * 12: descriptor count

 */

#define REG_TX_RING_BASE    0x00000

​

/*

 * 16 bytes per entry, one entry for every hop (REG_HOP_COUNT)

 * 00: physical pointer to an array of struct ring_desc

 * 08: ring head (index of first not posted descriptor)

 * 10: ring tail (set by NHI)

 * 12: descriptor count

 * 14: max frame sizes (anything larger than 0x100 has no effect)

 */

#define REG_RX_RING_BASE    0x08000

​

/*

 * 32 bytes per entry, one entry for every hop (REG_HOP_COUNT)

 * 00: enum_ring_flags

 * 04: isoch time stamp ?? (write 0)

 * ..: unknown

 */