rtt-f030/bsp/ls1cdev/libraries/ls1c_spi.c

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/*
* File : ls1c_spi.c
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2006 - 2012, RT-Thread Development Team
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Change Logs:
* Date Author Notes
* 2017-10-23 勤为本 first version
*/
// 硬件spi接口源文件
#include <string.h>
#include "ls1c_public.h"
#include "ls1c_regs.h"
#include "ls1c_clock.h"
#include "ls1c_spi.h"
// 寄存器偏移
#define LS1C_SPI_SPCR_OFFSET (0) // 控制寄存器
#define LS1C_SPI_SPSR_OFFSET (1) // 状态寄存器
#define LS1C_SPI_TxFIFO_OFFSET (2) // 发送的数据寄存器,与接收数据寄存器的偏移相同
#define LS1C_SPI_RxFIFO_OFFSET (2) // 接收的数据寄存器,与发送数据寄存器的偏移相同
#define LS1C_SPI_SPER_OFFSET (3) // 外部寄存器
#define LS1C_SPI_SFC_PARAM_OFFSET (4) // 参数控制寄存器
#define LS1C_SPI_SFC_SOFTCS_OFFSET (5) // 片选控制寄存器
#define LS1C_SPI_SFC_TIMING_OFFSET (6) // 时序控制寄存器
// 寄存器SPCR中的位域
#define LS1C_SPI_SPCR_SPIE_BIT (7)
#define LS1C_SPI_SPCR_SPIE_MASK (0x01 << LS1C_SPI_SPCR_SPIE_BIT)
#define LS1C_SPI_SPCR_SPE_BIT (6)
#define LS1C_SPI_SPCR_SPE_MASK (0x01 << LS1C_SPI_SPCR_SPE_BIT)
#define LS1C_SPI_SPCR_CPOL_BIT (3)
#define LS1C_SPI_SPCR_CPOL_MASK (0x01 << LS1C_SPI_SPCR_CPOL_BIT)
#define LS1C_SPI_SPCR_CPHA_BIT (2)
#define LS1C_SPI_SPCR_CPHA_MASK (0x01 << LS1C_SPI_SPCR_CPHA_BIT)
#define LS1C_SPI_SPCR_SPR_BIT (0)
#define LS1C_SPI_SPCR_SPR_MASK (0x03 << LS1C_SPI_SPCR_SPR_BIT)
// 寄存器SPSR中的位域
#define LS1C_SPI_SPSR_SPIF_BIT (7)
#define LS1C_SPI_SPSR_SPIF_MASK (0x01 << LS1C_SPI_SPSR_SPIF_BIT)
#define LS1C_SPI_SPSR_WCOL_BIT (6)
#define LS1C_SPI_SPSR_WCOL_MASK (0x01 << LS1C_SPI_SPSR_WCOL_BIT)
// 寄存器SPER中的位域
#define LS1C_SPI_SPER_SPRE_BIT (0)
#define LS1C_SPI_SPER_SPRE_MASK (0x3 << LS1C_SPI_SPER_SPRE_BIT)
// 寄存器SFC_SOFTCS的位域
#define LS1C_SPI_SFC_SOFTCS_CSN_BIT (4)
#define LS1C_SPI_SFC_SOFTCS_CSN_MASK (0x0f << LS1C_SPI_SFC_SOFTCS_CSN_BIT)
#define LS1C_SPI_SFC_SOFTCS_CSEN_BIT (0)
#define LS1C_SPI_SFC_SOFTCS_CSEN_MASK (0x0f << LS1C_SPI_SFC_SOFTCS_CSEN_BIT)
// 发送超时的门限值
#define LS1C_SPI_TX_TIMEOUT (20000)
/*
* 获取指定SPI模块的基地址
* @SPIx SPI模块的编号
*/
inline void *spi_get_base(ls1c_spi_t SPIx)
{
void *base = NULL;
switch (SPIx)
{
case LS1C_SPI_0:
base = (void *)LS1C_SPI0_BASE;
break;
case LS1C_SPI_1:
base = (void *)LS1C_SPI1_BASE;
break;
default:
base = NULL;
break;
}
return base;
}
/*
* 打印指定SPI模块的所有寄存器的值
* @spi_info_p SPI模块信息
*/
void spi_print_all_regs_info(ls1c_spi_info_t *spi_info_p)
{
void *spi_base = spi_get_base(spi_info_p->SPIx);
rt_kprintf("[%s] SPI%d's info:\r\n\
SPCR=0x%x, SPSR=0x%x, SPER=0x%x, SFC_PARAM=0x%x, SFC_SOFTCS=0x%x, SFC_TIMING=0x%x\r\n",
__FUNCTION__, spi_info_p->SPIx,
reg_read_8(spi_base + LS1C_SPI_SPCR_OFFSET),
reg_read_8(spi_base + LS1C_SPI_SPSR_OFFSET),
reg_read_8(spi_base + LS1C_SPI_SPER_OFFSET),
reg_read_8(spi_base + LS1C_SPI_SFC_PARAM_OFFSET),
reg_read_8(spi_base + LS1C_SPI_SFC_SOFTCS_OFFSET),
reg_read_8(spi_base + LS1C_SPI_SFC_TIMING_OFFSET));
return ;
}
/*
* 根据SPI时钟频率计算分频系数
* @max_speed_hz SPI最大通信速度
* @ret 分频系数
*/
unsigned int spi_get_div(unsigned int max_speed_hz)
{
unsigned long clk = 0;
unsigned int div = 0;
unsigned int div_tmp = 0;
unsigned int bit = 0;
clk = clk_get_apb_rate();
div = DIV_ROUND_UP(clk, max_speed_hz);
if (div < 2)
div = 2;
if (div > 4096)
div = 4096;
bit = ls1c_fls(div) - 1;
switch (1 << bit)
{
case 16:
div_tmp = 2;
if (div > (1 << bit))
{
div_tmp++;
}
break;
case 32:
div_tmp = 3;
if (div > (1 << bit))
{
div_tmp += 2;
}
break;
case 8:
div_tmp = 4;
if (div > (1 << bit))
{
div_tmp -= 2;
}
break;
default:
div_tmp = bit - 1;
if (div > (1 << bit))
{
div_tmp++;
}
break;
}
/*
rt_kprintf("[%s] clk=%ld, max_speed_hz=%d, div_tmp=%d, bit=%d\r\n",
__FUNCTION__, clk, max_speed_hz, div_tmp, bit);
*/
return div_tmp;
}
/*
* 设置时钟
* @spi_info_p SPI模块信息
*/
void spi_set_clock(ls1c_spi_info_t *spi_info_p)
{
void *spi_base = spi_get_base(spi_info_p->SPIx);
unsigned int div = 0;
unsigned char val = 0;
// 获取分频系数
div = spi_get_div(spi_info_p->max_speed_hz);
// 设置spr
val = reg_read_8(spi_base + LS1C_SPI_SPCR_OFFSET);
val &= (~LS1C_SPI_SPCR_SPR_MASK); // spr清零
val |= (div & LS1C_SPI_SPCR_SPR_MASK); // 设置新的spr
reg_write_8(val, spi_base + LS1C_SPI_SPCR_OFFSET);
// 设置spre
val = reg_read_8(spi_base + LS1C_SPI_SPER_OFFSET);
val &= (~LS1C_SPI_SPER_SPRE_MASK); // spre清零
val |= ((div >> 2) & LS1C_SPI_SPER_SPRE_MASK); // 设置新的spre
reg_write_8(val, spi_base + LS1C_SPI_SPER_OFFSET);
return ;
}
/*
* 设置通信模式(时钟极性和相位)
* @spi_info_p SPI模块信息
*/
void spi_set_mode(ls1c_spi_info_t *spi_info_p)
{
void *spi_base = spi_get_base(spi_info_p->SPIx);
unsigned char val = 0;
val = reg_read_8(spi_base + LS1C_SPI_SPCR_OFFSET);
// 设置时钟极性--cpol
val &= (~LS1C_SPI_SPCR_CPOL_MASK); // cpol清0
val |= (spi_info_p->cpol << LS1C_SPI_SPCR_CPOL_BIT); // 写入新的cpol
// 设置时钟相位--cpha
val &= (~LS1C_SPI_SPCR_CPHA_MASK); // cpha清0
val |= (spi_info_p->cpha << LS1C_SPI_SPCR_CPHA_BIT); // 写入新的cpha
reg_write_8(val, spi_base + LS1C_SPI_SPCR_OFFSET);
return ;
}
/*
* 设置指定片选为指定状态
* @spi_info_p SPI模块信息
* @new_status 片选引脚的新状态取值为0或1即高电平或低电平
*/
void spi_set_cs(ls1c_spi_info_t *spi_info_p, int new_status)
{
void *spi_base = spi_get_base(spi_info_p->SPIx);
unsigned char cs = spi_info_p->cs;
unsigned char val = 0;
val = 0xf0 | (0x01 << cs); // 全部csn=1指定的csen=1
if (new_status) // cs = 1
{
val |= (0x10 << cs); // 指定csn=1
}
else // cs = 0
{
val &= ~(0x10 << cs); // 指定csn=0
}
reg_write_8(val, spi_base + LS1C_SPI_SFC_SOFTCS_OFFSET);
return ;
}
/*
* 初始化指定SPI模块
* @spi_info_p SPI模块信息
*/
void spi_init(ls1c_spi_info_t *spi_info_p)
{
void *spi_base = spi_get_base(spi_info_p->SPIx);
unsigned char val = 0;
// 使能SPI控制器master模式关闭中断
reg_write_8(0x53, spi_base + LS1C_SPI_SPCR_OFFSET);
// 清空状态寄存器
reg_write_8(0xc0, spi_base + LS1C_SPI_SPSR_OFFSET);
// 1字节产生中断采样(读)与发送(写)时机同时
reg_write_8(0x03, spi_base + LS1C_SPI_SPER_OFFSET);
// 关闭SPI flash
val = reg_read_8(spi_base + LS1C_SPI_SFC_PARAM_OFFSET);
val &= 0xfe;
reg_write_8(val, spi_base + LS1C_SPI_SFC_PARAM_OFFSET);
// spi flash时序控制寄存器
reg_write_8(0x05, spi_base + LS1C_SPI_SFC_TIMING_OFFSET);
// 设置时钟
spi_set_clock(spi_info_p);
// 设置通信模式(时钟极性和相位)
spi_set_mode(spi_info_p);
// 打印寄存器信息(用于调试)
// spi_print_all_regs_info(spi_info_p);
return ;
}
/*
* 等待收发完成
*/
inline void spi_wait_txrx_done(ls1c_spi_info_t *spi_info_p)
{
void *spi_base = spi_get_base(spi_info_p->SPIx);
int timeout = LS1C_SPI_TX_TIMEOUT;
while (timeout--)
{
if (LS1C_SPI_SPSR_SPIF_MASK & reg_read_8(spi_base + LS1C_SPI_SPSR_OFFSET))
break;
}
return ;
}
/*
* 清中断和标志位
*/
inline void spi_clear(ls1c_spi_info_t *spi_info_p)
{
void *spi_base = spi_get_base(spi_info_p->SPIx);
unsigned char val = 0;
// 清中断
val = reg_read_8(spi_base + LS1C_SPI_SPSR_OFFSET);
val |= LS1C_SPI_SPSR_SPIF_MASK;
reg_write_8(val, spi_base + LS1C_SPI_SPSR_OFFSET);
// 清溢出标志位(Write-Collision Clear)
val = reg_read_8(spi_base + LS1C_SPI_SPSR_OFFSET);
if (LS1C_SPI_SPSR_WCOL_MASK & val)
{
rt_kprintf("[%s] clear register SPSR's wcol!\r\n"); // 手册和linux源码中不一样加个打印看看
reg_write_8(val & ~LS1C_SPI_SPSR_WCOL_MASK, spi_base + LS1C_SPI_SPSR_OFFSET); // 写0linux源码中是写0
// reg_write_8(val | LS1C_SPI_SPSR_WCOL_MASK, spi_base + LS1C_SPI_SPSR_OFFSET); // 写1按照1c手册应该写1
}
return ;
}
/*
* 通过指定SPI发送接收一个字节
* 注意,在多任务的系统中,此函数需要互斥。
* 即保证在和某个从设备收发某个字节的过程中不能被切换到其它任务同时与另外的在同一个SPI总线上的从设备通信
* 因为龙芯1c的每路SPI上可能接有不同的从设备通信频率、模式等可能不同
* @spi_info_p SPI接口
* @tx_ch 待发送的数据
* @ret 收到的数据
*/
unsigned char spi_txrx_byte(ls1c_spi_info_t *spi_info_p, unsigned char tx_ch)
{
void *spi_base = spi_get_base(spi_info_p->SPIx);
unsigned char rx_ch = 0;
// 收发数据
reg_write_8(tx_ch, spi_base + LS1C_SPI_TxFIFO_OFFSET); // 开始发送
spi_wait_txrx_done(spi_info_p); // 等待收发完成
rx_ch = reg_read_8(spi_base + LS1C_SPI_RxFIFO_OFFSET); // 读取收到的数据
spi_clear(spi_info_p); // 清中断和标志位
return rx_ch;
}