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Refactoring

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This commit is contained in:
Daniil Gentili 2022-06-20 18:06:23 +02:00
parent 01af0bade1
commit 6536272d32
Signed by: danog
GPG Key ID: 8C1BE3B34B230CA7
3 changed files with 12 additions and 96 deletions
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13
include/mini_uart.h
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@ -1,6 +1,11 @@
#pragma once
void uart_init(void);
void uart_send(char c);
char uart_recv();
void uart_send_string(const char *str);
void uart0_init(void);
void uart0_send(char c);
char uart0_recv();
void uart0_send_string(const char *str);
void uart1_init(void);
void uart1_send(char c);
char uart1_recv();
void uart1_send_string(const char *str);

6
src/kernel.c
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@ -4,10 +4,10 @@
void kernel_main(void)
{
uart_init();
uart_send_string("Hello, world!\r\n");
uart0_init();
uart0_send_string("Hello, world!\r\n");
while (1) {
uart_send(uart_recv());
uart0_send(uart0_recv());
}
}

89
src/mini_uart.c
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@ -1,89 +0,0 @@
#include "mini_uart.h"
#include "reg.h"
#define UART_DR (UART_BASE+0x0)
#define UART_FR (UART_BASE+0x18)
#define UART_IBRD (UART_BASE+0x24)
#define UART_FBRD (UART_BASE+0x28)
#define UART_LCRH (UART_BASE+0x2C)
#define UART_CR (UART_BASE+0x30)
#define UART_ICR (UART_BASE+0x44)
// UART clock baud rate divisor register
// Why is this undocumented??
#define CM_UARTDIV (0x7e1010f4-BUS_OFFSET)
// UART control register
// Why is this undocumented??
#define CM_UARTCTL 0x7e1010f0
// cucumber moment
#define CM_PASSWORD 0x5a000000
#define CM_SRC_OSC 1
#define CM_UARTCTL_FRAC_SET 0x00000200
#define CM_UARTCTL_ENAB_SET 0x00000010
void uart_init(void)
{
unsigned int selector;
selector = get32(GPFSEL1);
selector &= ~(7<<12); // clean gpio14
selector |= 4<<12; // set alt1 for gpio14
selector &= ~(7<<15); // clean gpio15
selector |= 4<<15; // set alt1 for gpio 15
put32(GPFSEL1,selector);
put32(UART_CR, 0);
put32(GPPUD,0);
delay(150);
put32(GPPUDCLK0,(1<<14)|(1<<15));
delay(150);
put32(GPPUDCLK0,0);
/*put32(AUX_ENABLES,1); //Enable mini uart (this also enables access to its registers)
put32(AUX_MU_CNTL_REG,0); //Disable auto flow control and disable receiver and transmitter (for now)
put32(AUX_MU_IER_REG,0); //Disable receive and transmit interrupts
put32(AUX_MU_LCR_REG,3); //Enable 8 bit mode
put32(AUX_MU_MCR_REG,0); //Set RTS line to be always high
put32(AUX_MU_BAUD_REG,270); //Set baud rate to 115200
put32(AUX_MU_CNTL_REG,3); //Finally, enable transmitter and receiver*/
put32(CM_UARTDIV, CM_PASSWORD | 0x6666);
put32(CM_UARTDIV, CM_PASSWORD | CM_SRC_OSC | CM_UARTCTL_FRAC_SET | CM_UARTCTL_ENAB_SET);
put32(UART_ICR, 0x7FF);
put32(UART_IBRD, 1);
put32(UART_FBRD, 40);
put32(UART_LCRH, 0x70);
put32(UART_CR, 0x301);
}
void uart_send(char c)
{
//while(!(get32(AUX_MU_LSR_REG) & 0x20));
//put32(AUX_MU_IO_REG, c);
while(get32(UART_FR) & 0x20);
put32(UART_DR, c);
}
char uart_recv()
{
//while (!(get32(AUX_MU_LSR_REG) & 0x1));
//return get32(AUX_MU_IO_REG) & 0xFF;
while(get32(UART_FR) & 0x10);
return put32(UART_DR) & 0xFF;
}
void uart_send_string(const char *str)
{
for (int i = 0; str[i] != '\0'; i++) {
uart_send(str[i]);
}
}