/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (C) 2018-2020 Oplus. All rights reserved.
 */

#ifndef _UFS_LATENCY_HIST_
#define _UFS_LATENCY_HIST_

#include <linux/types.h>
#include <linux/kernel.h>

/*
 * X-axis for IO latency histogram support.
 */
static const u_int64_t latency_x_axis_us[] = {
   100,
   200,
   300,
   400,
   500,
   600,
   700,
   800,
   900,
   1000,
   2000,
   3000,
   4000,
   5000,
   6000,
   7000,
   8000,
   9000,
   10000,
   20000,
   30000,
   40000,
   50000,
   100000,
   200000,
   300000,
   400000,
   500000,
   600000,
   700000,
   800000,
   900000,
   1000000,
   1500000,
   2000000
};

#define IO_LAT_HIST_DISABLE         0
#define IO_LAT_HIST_ENABLE          1
#define IO_LAT_HIST_ZERO            2
#define CHUNCK_SIZE_4K                  8
#define CHUNCK_SIZE_8K                  16
#define CHUNCK_SIZE_32K                 64
#define CHUNCK_SIZE_64K                 128
#define CHUNCK_SIZE_128K                256
#define CHUNCK_SIZE_256K                512

struct io_latency_chunck_size {
   u_int64_t   chunk_0_count;
	u_int64_t	chunk_4k_count;
	u_int64_t   chunk_8k_count;
	u_int64_t   chunk_8_32k_count;
	u_int64_t   chunk_32_64k_count;
	u_int64_t   chunk_64_128k_count;
	u_int64_t   chunk_128_256k_count;
	u_int64_t   chunk_above_256k_count;
	u_int64_t   latency_axis;
};

struct io_latency_state {
	struct io_latency_chunck_size latency_y_axis[ARRAY_SIZE(latency_x_axis_us) + 1];
	u_int64_t	latency_elems;
	u_int64_t	latency_sum;
};

static inline void
io_update_latency_hist(struct io_latency_state *s, u_int64_t delta_us, unsigned int length)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(latency_x_axis_us); i++)
		if (delta_us < (u_int64_t)latency_x_axis_us[i])
			break;
	s->latency_y_axis[i].latency_axis++;
	if(!length){
      s->latency_y_axis[i].chunk_0_count++;
	}else if( length > CHUNCK_SIZE_256K){
	   s->latency_y_axis[i].chunk_above_256k_count++;
	}else if( length > CHUNCK_SIZE_128K ){
      s->latency_y_axis[i].chunk_128_256k_count++;
	}else if( length > CHUNCK_SIZE_64K ){
      s->latency_y_axis[i].chunk_64_128k_count++;
	}else if( length > CHUNCK_SIZE_32K ){
      s->latency_y_axis[i].chunk_32_64k_count++;
	}else if( length > CHUNCK_SIZE_8K ){
      s->latency_y_axis[i].chunk_8_32k_count++;
	}else if( length == CHUNCK_SIZE_8K){
      s->latency_y_axis[i].chunk_8k_count++;
	}else if( length == CHUNCK_SIZE_4K ){
      s->latency_y_axis[i].chunk_4k_count++;
	}
	s->latency_elems++;
	s->latency_sum += delta_us;
}

ssize_t io_latency_hist_show(char* name, struct io_latency_state *s,
		char *buf, int buf_size);

#endif