/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (C) 2014 Texas Instruments Incorporated
 * Authors:     Sandeep Nair <sandeep_n@ti.com
 *              Cyril Chemparathy <cyril@ti.com
                Santosh Shilimkar <santosh.shilimkar@ti.com>
 */

#ifndef __SOC_TI_KEYSTONE_NAVIGATOR_DMA_H__
#define __SOC_TI_KEYSTONE_NAVIGATOR_DMA_H__

#include <linux/dmaengine.h>

/*
 * PKTDMA descriptor manipulation macros for host packet descriptor
 */
#define MASK(x)                                 (BIT(x) - 1)
#define KNAV_DMA_DESC_PKT_LEN_MASK              MASK(22)
#define KNAV_DMA_DESC_PKT_LEN_SHIFT             0
#define KNAV_DMA_DESC_PS_INFO_IN_SOP            BIT(22)
#define KNAV_DMA_DESC_PS_INFO_IN_DESC           0
#define KNAV_DMA_DESC_TAG_MASK                  MASK(8)
#define KNAV_DMA_DESC_SAG_HI_SHIFT              24
#define KNAV_DMA_DESC_STAG_LO_SHIFT             16
#define KNAV_DMA_DESC_DTAG_HI_SHIFT             8
#define KNAV_DMA_DESC_DTAG_LO_SHIFT             0
#define KNAV_DMA_DESC_HAS_EPIB                  BIT(31)
#define KNAV_DMA_DESC_NO_EPIB                   0
#define KNAV_DMA_DESC_PSLEN_SHIFT               24
#define KNAV_DMA_DESC_PSLEN_MASK                MASK(6)
#define KNAV_DMA_DESC_ERR_FLAG_SHIFT            20
#define KNAV_DMA_DESC_ERR_FLAG_MASK             MASK(4)
#define KNAV_DMA_DESC_PSFLAG_SHIFT              16
#define KNAV_DMA_DESC_PSFLAG_MASK               MASK(4)
#define KNAV_DMA_DESC_RETQ_SHIFT                0
#define KNAV_DMA_DESC_RETQ_MASK                 MASK(14)
#define KNAV_DMA_DESC_BUF_LEN_MASK              MASK(22)
#define KNAV_DMA_DESC_EFLAGS_MASK               MASK(4)
#define KNAV_DMA_DESC_EFLAGS_SHIFT              20

#define KNAV_DMA_NUM_EPIB_WORDS                 4
#define KNAV_DMA_NUM_PS_WORDS                   16
#define KNAV_DMA_NUM_SW_DATA_WORDS              4
#define KNAV_DMA_FDQ_PER_CHAN                   4

/* Tx channel scheduling priority */
enum knav_dma_tx_priority {
        DMA_PRIO_HIGH   = 0,
        DMA_PRIO_MED_H,
        DMA_PRIO_MED_L,
        DMA_PRIO_LOW
};

/* Rx channel error handling mode during buffer starvation */
enum knav_dma_rx_err_mode {
        DMA_DROP = 0,
        DMA_RETRY
};

/* Rx flow size threshold configuration */
enum knav_dma_rx_thresholds {
        DMA_THRESH_NONE         = 0,
        DMA_THRESH_0            = 1,
        DMA_THRESH_0_1          = 3,
        DMA_THRESH_0_1_2        = 7
};

/* Descriptor type */
enum knav_dma_desc_type {
        DMA_DESC_HOST = 0,
        DMA_DESC_MONOLITHIC = 2
};

/**
 * struct knav_dma_tx_cfg:      Tx channel configuration
 * @filt_einfo:                 Filter extended packet info
 * @filt_pswords:               Filter PS words present
 * @knav_dma_tx_priority:       Tx channel scheduling priority
 */
struct knav_dma_tx_cfg {
        bool                            filt_einfo;
        bool                            filt_pswords;
        enum knav_dma_tx_priority       priority;
};

/**
 * struct knav_dma_rx_cfg:      Rx flow configuration
 * @einfo_present:              Extended packet info present
 * @psinfo_present:             PS words present
 * @knav_dma_rx_err_mode:       Error during buffer starvation
 * @knav_dma_desc_type: Host or Monolithic desc
 * @psinfo_at_sop:              PS word located at start of packet
 * @sop_offset:                 Start of packet offset
 * @dst_q:                      Destination queue for a given flow
 * @thresh:                     Rx flow size threshold
 * @fdq[]:                      Free desc Queue array
 * @sz_thresh0:                 RX packet size threshold 0
 * @sz_thresh1:                 RX packet size threshold 1
 * @sz_thresh2:                 RX packet size threshold 2
 */
struct knav_dma_rx_cfg {
        bool                            einfo_present;
        bool                            psinfo_present;
        enum knav_dma_rx_err_mode       err_mode;
        enum knav_dma_desc_type         desc_type;
        bool                            psinfo_at_sop;
        unsigned int                    sop_offset;
        unsigned int                    dst_q;
        enum knav_dma_rx_thresholds     thresh;
        unsigned int                    fdq[KNAV_DMA_FDQ_PER_CHAN];
        unsigned int                    sz_thresh0;
        unsigned int                    sz_thresh1;
        unsigned int                    sz_thresh2;
};

/**
 * struct knav_dma_cfg: Pktdma channel configuration
 * @sl_cfg:                     Slave configuration
 * @tx:                         Tx channel configuration
 * @rx:                         Rx flow configuration
 */
struct knav_dma_cfg {
        enum dma_transfer_direction direction;
        union {
                struct knav_dma_tx_cfg  tx;
                struct knav_dma_rx_cfg  rx;
        } u;
};

/**
 * struct knav_dma_desc:        Host packet descriptor layout
 * @desc_info:                  Descriptor information like id, type, length
 * @tag_info:                   Flow tag info written in during RX
 * @packet_info:                Queue Manager, policy, flags etc
 * @buff_len:                   Buffer length in bytes
 * @buff:                       Buffer pointer
 * @next_desc:                  For chaining the descriptors
 * @orig_len:                   length since 'buff_len' can be overwritten
 * @orig_buff:                  buff pointer since 'buff' can be overwritten
 * @epib:                       Extended packet info block
 * @psdata:                     Protocol specific
 * @sw_data:                    Software private data not touched by h/w
 */
struct knav_dma_desc {
        __le32  desc_info;
        __le32  tag_info;
        __le32  packet_info;
        __le32  buff_len;
        __le32  buff;
        __le32  next_desc;
        __le32  orig_len;
        __le32  orig_buff;
        __le32  epib[KNAV_DMA_NUM_EPIB_WORDS];
        __le32  psdata[KNAV_DMA_NUM_PS_WORDS];
        u32     sw_data[KNAV_DMA_NUM_SW_DATA_WORDS];
} ____cacheline_aligned;

#if IS_ENABLED(CONFIG_KEYSTONE_NAVIGATOR_DMA)
void *knav_dma_open_channel(struct device *dev, const char *name,
                                struct knav_dma_cfg *config);
void knav_dma_close_channel(void *channel);
int knav_dma_get_flow(void *channel);
bool knav_dma_device_ready(void);
#else
static inline void *knav_dma_open_channel(struct device *dev, const char *name,
                                struct knav_dma_cfg *config)
{
        return (void *) NULL;
}
static inline void knav_dma_close_channel(void *channel)
{}

static inline int knav_dma_get_flow(void *channel)
{
        return -EINVAL;
}

static inline bool knav_dma_device_ready(void)
{
        return false;
}

#endif

#endif /* __SOC_TI_KEYSTONE_NAVIGATOR_DMA_H__ */