1 /******************************************************************************
2 *
3 * Copyright (C) 2022-2023 Maxim Integrated Products, Inc. (now owned by
4 * Analog Devices, Inc.),
5 * Copyright (C) 2023-2024 Analog Devices, Inc.
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 *
19 ******************************************************************************/
20
21 #include <string.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include "max32690.h"
25 #include "gcr_regs.h"
26 #include "icc.h"
27 #include "mxc_sys.h"
28
29 uint32_t SystemCoreClock;
30
31 /*
32 The libc implementation from GCC 11+ depends on _getpid and _kill in some places.
33 There is no concept of processes/PIDs in the baremetal PeriphDrivers, therefore
34 we implement stub functions that return an error code to resolve linker warnings.
35 */
_getpid(void)36 __weak int _getpid(void)
37 {
38 return E_NOT_SUPPORTED;
39 }
40
_kill(void)41 __weak int _kill(void)
42 {
43 return E_NOT_SUPPORTED;
44 }
45
SystemCoreClockUpdate(void)46 __weak void SystemCoreClockUpdate(void)
47 {
48 uint32_t base_freq, div, clk_src;
49
50 // Get the clock source and frequency
51 clk_src = (MXC_GCR->clkctrl & MXC_F_GCR_CLKCTRL_SYSCLK_SEL);
52 switch (clk_src) {
53 case MXC_S_GCR_CLKCTRL_SYSCLK_SEL_EXTCLK:
54 base_freq = EXTCLK_FREQ;
55 break;
56 case MXC_S_GCR_CLKCTRL_SYSCLK_SEL_INRO:
57 base_freq = INRO_FREQ;
58 break;
59 case MXC_S_GCR_CLKCTRL_SYSCLK_SEL_IPO:
60 base_freq = IPO_FREQ;
61 break;
62 case MXC_S_GCR_CLKCTRL_SYSCLK_SEL_IBRO:
63 base_freq = IBRO_FREQ;
64 break;
65 case MXC_S_GCR_CLKCTRL_SYSCLK_SEL_ISO:
66 base_freq = ISO_FREQ;
67 break;
68 case MXC_S_GCR_CLKCTRL_SYSCLK_SEL_ERTCO:
69 base_freq = ERTCO_FREQ;
70 break;
71 case MXC_S_GCR_CLKCTRL_SYSCLK_SEL_ERFO:
72 base_freq = ERFO_FREQ;
73 break;
74 default:
75 // Codes 001 and 111 are reserved.
76 // This code should never execute, however, initialize to safe value.
77 base_freq = HIRC_FREQ;
78 break;
79 }
80
81 div = (MXC_GCR->clkctrl & MXC_F_GCR_CLKCTRL_SYSCLK_DIV) >> MXC_F_GCR_CLKCTRL_SYSCLK_DIV_POS;
82
83 SystemCoreClock = base_freq >> div;
84 }
85
86 /* This function is called before C runtime initialization and can be
87 * implemented by the application for early initializations. If a value other
88 * than '0' is returned, the C runtime initialization will be skipped.
89 *
90 * You may over-ride this function in your program by defining a custom
91 * PreInit(), but care should be taken to reproduce the initilization steps
92 * or a non-functional system may result.
93 */
PreInit(void)94 __weak int PreInit(void)
95 {
96 /* Do nothing */
97 return 0;
98 }
99
100 /* This function can be implemented by the application to initialize the board */
Board_Init(void)101 __weak int Board_Init(void)
102 {
103 /* Do nothing */
104 return 0;
105 }
106
107 /* Cordio library init function */
PalSysInit(void)108 __weak void PalSysInit(void) {}
109
__enable_irq(void)110 void __enable_irq(void)
111 {
112 // Set the MIE bit if we're outside the interrupt context
113 __asm volatile("csrw mstatus, 0x8");
114 }
115
116 /* This function is called just before control is transferred to main().
117 *
118 * You may over-ride this function in your program by defining a custom
119 * SystemInit(), but care should be taken to reproduce the initialization
120 * steps or a non-functional system may result.
121 */
SystemInit(void)122 __weak void SystemInit(void)
123 {
124 SystemCoreClockUpdate();
125
126 MXC_ICC_Enable(MXC_ICC1);
127
128 __enable_irq();
129
130 Board_Init();
131
132 PalSysInit();
133 }
134
