1 |
2 |
zero_gravi |
// #################################################################################################
|
2 |
10 |
zero_gravi |
// # << NEORV32: neorv32_spi.c - Serial Peripheral Interface Controller (SPI) HW Driver >> #
|
3 |
2 |
zero_gravi |
// # ********************************************************************************************* #
|
4 |
|
|
// # BSD 3-Clause License #
|
5 |
|
|
// # #
|
6 |
|
|
// # Copyright (c) 2020, Stephan Nolting. All rights reserved. #
|
7 |
|
|
// # #
|
8 |
|
|
// # Redistribution and use in source and binary forms, with or without modification, are #
|
9 |
|
|
// # permitted provided that the following conditions are met: #
|
10 |
|
|
// # #
|
11 |
|
|
// # 1. Redistributions of source code must retain the above copyright notice, this list of #
|
12 |
|
|
// # conditions and the following disclaimer. #
|
13 |
|
|
// # #
|
14 |
|
|
// # 2. Redistributions in binary form must reproduce the above copyright notice, this list of #
|
15 |
|
|
// # conditions and the following disclaimer in the documentation and/or other materials #
|
16 |
|
|
// # provided with the distribution. #
|
17 |
|
|
// # #
|
18 |
|
|
// # 3. Neither the name of the copyright holder nor the names of its contributors may be used to #
|
19 |
|
|
// # endorse or promote products derived from this software without specific prior written #
|
20 |
|
|
// # permission. #
|
21 |
|
|
// # #
|
22 |
|
|
// # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS #
|
23 |
|
|
// # OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF #
|
24 |
|
|
// # MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE #
|
25 |
|
|
// # COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, #
|
26 |
|
|
// # EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE #
|
27 |
|
|
// # GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED #
|
28 |
|
|
// # AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING #
|
29 |
|
|
// # NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED #
|
30 |
|
|
// # OF THE POSSIBILITY OF SUCH DAMAGE. #
|
31 |
|
|
// # ********************************************************************************************* #
|
32 |
|
|
// # The NEORV32 Processor - https://github.com/stnolting/neorv32 (c) Stephan Nolting #
|
33 |
|
|
// #################################################################################################
|
34 |
|
|
|
35 |
|
|
|
36 |
|
|
/**********************************************************************//**
|
37 |
|
|
* @file neorv32_spi.c
|
38 |
|
|
* @author Stephan Nolting
|
39 |
10 |
zero_gravi |
* @brief Serial peripheral interface controller (SPI) HW driver source file.
|
40 |
2 |
zero_gravi |
*
|
41 |
|
|
* @note These functions should only be used if the SPI unit was synthesized (IO_SPI_USE = true).
|
42 |
|
|
**************************************************************************/
|
43 |
|
|
|
44 |
|
|
#include "neorv32.h"
|
45 |
|
|
#include "neorv32_spi.h"
|
46 |
|
|
|
47 |
|
|
|
48 |
|
|
/**********************************************************************//**
|
49 |
|
|
* Check if SPI unit was synthesized.
|
50 |
|
|
*
|
51 |
|
|
* @return 0 if SPI was not synthesized, 1 if SPI is available.
|
52 |
|
|
**************************************************************************/
|
53 |
|
|
int neorv32_spi_available(void) {
|
54 |
|
|
|
55 |
12 |
zero_gravi |
if (SYSINFO_FEATURES & (1 << SYSINFO_FEATURES_IO_SPI)) {
|
56 |
2 |
zero_gravi |
return 1;
|
57 |
|
|
}
|
58 |
|
|
else {
|
59 |
|
|
return 0;
|
60 |
|
|
}
|
61 |
|
|
}
|
62 |
|
|
|
63 |
|
|
|
64 |
|
|
/**********************************************************************//**
|
65 |
|
|
* Enable and configure SPI controller. The SPI control register bits are listed in #NEORV32_SPI_CT_enum.
|
66 |
|
|
*
|
67 |
|
|
* @param[in] prsc Clock prescaler select (0..7). See #NEORV32_CLOCK_PRSC_enum.
|
68 |
|
|
* @param[in] clk_polarity Idle clock polarity (0, 1).
|
69 |
|
|
* @param[in] dir Shift direction (0: MSB first, 1: LSB first).
|
70 |
|
|
* @param[in] data_size Data transfer size (0: 8-bit, 1: 16-bit, 2: 24-bit, 3: 32-bit).
|
71 |
|
|
* @param[in] irq_en Enable transfer-done interrupt when 1.
|
72 |
|
|
**************************************************************************/
|
73 |
|
|
void neorv32_spi_setup(uint8_t prsc, uint8_t clk_polarity, uint8_t dir, uint8_t data_size, uint8_t irq_en) {
|
74 |
|
|
|
75 |
|
|
SPI_CT = 0; // reset
|
76 |
|
|
|
77 |
|
|
uint32_t ct_enable = 1;
|
78 |
|
|
ct_enable = ct_enable << SPI_CT_EN;
|
79 |
|
|
|
80 |
|
|
uint32_t ct_prsc = (uint32_t)(prsc & 0x07);
|
81 |
|
|
ct_prsc = ct_prsc << SPI_CT_PRSC0;
|
82 |
|
|
|
83 |
|
|
uint32_t ct_polarity = (uint32_t)(clk_polarity & 0x01);
|
84 |
|
|
ct_polarity = ct_polarity << SPI_CT_CPHA;
|
85 |
|
|
|
86 |
|
|
uint32_t ct_dir = (uint32_t)(dir & 0x01);
|
87 |
|
|
ct_dir = ct_dir << SPI_CT_DIR;
|
88 |
|
|
|
89 |
|
|
uint32_t ct_size = (uint32_t)(data_size & 0x03);
|
90 |
|
|
ct_size = ct_size << SPI_CT_SIZE0;
|
91 |
|
|
|
92 |
|
|
uint32_t ct_irq = (uint32_t)(irq_en & 0x01);
|
93 |
|
|
ct_irq = ct_irq << SPI_CT_IRQ_EN;
|
94 |
|
|
|
95 |
|
|
SPI_CT = ct_enable | ct_prsc | ct_polarity | ct_dir | ct_size | ct_irq;
|
96 |
|
|
}
|
97 |
|
|
|
98 |
|
|
|
99 |
|
|
/**********************************************************************//**
|
100 |
|
|
* Disable and SPI controller.
|
101 |
|
|
**************************************************************************/
|
102 |
|
|
void neorv32_spi_disable(void) {
|
103 |
|
|
|
104 |
|
|
SPI_CT &= ~((uint32_t)(1 << SPI_CT_EN));
|
105 |
|
|
}
|
106 |
|
|
|
107 |
|
|
|
108 |
|
|
/**********************************************************************//**
|
109 |
|
|
* Activate SPI chip select signal.
|
110 |
|
|
*
|
111 |
|
|
* @note The chip select output lines are LOW when activated.
|
112 |
|
|
*
|
113 |
|
|
* @param cs Chip select line to activate (0..7).
|
114 |
|
|
**************************************************************************/
|
115 |
|
|
void neorv32_spi_cs_en(uint8_t cs) {
|
116 |
|
|
|
117 |
|
|
uint32_t cs_mask = (uint32_t)(1 << (cs & 0x07));
|
118 |
|
|
cs_mask = cs_mask << SPI_CT_CS0;
|
119 |
|
|
SPI_CT |= cs_mask;
|
120 |
|
|
}
|
121 |
|
|
|
122 |
|
|
|
123 |
|
|
/**********************************************************************//**
|
124 |
|
|
* Deactivate SPI chip select signal.
|
125 |
|
|
*
|
126 |
|
|
* @note The chip select output lines are HIGH when deactivated.
|
127 |
|
|
*
|
128 |
|
|
* @param cs Chip select line to deactivate (0..7).
|
129 |
|
|
**************************************************************************/
|
130 |
|
|
void neorv32_spi_cs_dis(uint8_t cs) {
|
131 |
|
|
|
132 |
|
|
uint32_t cs_mask = (uint32_t)(1 << (cs & 0x07));
|
133 |
|
|
cs_mask = cs_mask << SPI_CT_CS0;
|
134 |
|
|
SPI_CT &= ~cs_mask;
|
135 |
|
|
}
|
136 |
|
|
|
137 |
|
|
|
138 |
|
|
/**********************************************************************//**
|
139 |
|
|
* Initiate SPI transfer.
|
140 |
|
|
*
|
141 |
|
|
* @note This function is blocking.
|
142 |
|
|
*
|
143 |
|
|
* @param tx_data Transmit data (8/16/24/32-bit, LSB-aligned).
|
144 |
|
|
* @return Receive data (8/16/24/32-bit, LSB-aligned).
|
145 |
|
|
**************************************************************************/
|
146 |
|
|
uint32_t neorv32_spi_trans(uint32_t tx_data) {
|
147 |
|
|
|
148 |
|
|
SPI_DATA = tx_data; // trigger transfer
|
149 |
|
|
while((SPI_CT & (1<<SPI_CT_BUSY)) != 0); // wait for current transfer to finish
|
150 |
|
|
|
151 |
|
|
return SPI_DATA;
|
152 |
|
|
}
|
153 |
23 |
zero_gravi |
|
154 |
|
|
|
155 |
|
|
/**********************************************************************//**
|
156 |
|
|
* Check if SPI transceiver is busy.
|
157 |
|
|
*
|
158 |
|
|
* @note This function is blocking.
|
159 |
|
|
*
|
160 |
|
|
* @return 0 if idle, 1 if busy
|
161 |
|
|
**************************************************************************/
|
162 |
|
|
int neorv32_spi_busy(void) {
|
163 |
|
|
|
164 |
|
|
if ((SPI_CT & (1<<SPI_CT_BUSY)) != 0) {
|
165 |
|
|
return 1;
|
166 |
|
|
}
|
167 |
|
|
return 0;
|
168 |
|
|
}
|