mirror of
https://github.com/cirosantilli/linux-kernel-module-cheat.git
synced 2026-01-23 02:05:57 +01:00
74b51fc044
The update is required to include 3c3ca64b5f0dd9eef7b1ce1c65cc6e8e9147dd38 otherwise baremetal does not on VExpress. baremetal: create a baremetal setup with crosstool-ng buildroot: improve directory location: move out/dl inside out/buildroot/download, and add a new out/buildroot/build level tagline: generalize, deliver more value than howto, since now howtos are starting to multiply rename all top scripts to separate words with hyphen more consistently, e.g. run-gdb instead of rungdb getvar: list all variables gem5: make m5out section to focus all releated information at Prevent m5term Text file busy when rebuilding gem5 while it is running.
66 lines
1.5 KiB
C
66 lines
1.5 KiB
C
#include <sys/stat.h>
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enum {
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UART_FR_RXFE = 0x10,
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};
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#define UART_DR(baseaddr) (*(unsigned int *)(baseaddr))
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#define UART_FR(baseaddr) (*(((unsigned int *)(baseaddr))+6))
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int _close(int file) { return -1; }
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int _fstat(int file, struct stat *st) {
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st->st_mode = S_IFCHR;
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return 0;
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}
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int _isatty(int file) { return 1; }
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int _lseek(int file, int ptr, int dir) { return 0; }
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int _open(const char *name, int flags, int mode) { return -1; }
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int _read(int file, char *ptr, int len) {
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int todo;
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if (len == 0)
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return 0;
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while (UART_FR(UART0_ADDR) & UART_FR_RXFE);
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*ptr++ = UART_DR(UART0_ADDR);
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for (todo = 1; todo < len; todo++) {
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if (UART_FR(UART0_ADDR) & UART_FR_RXFE) {
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break;
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}
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*ptr++ = UART_DR(UART0_ADDR);
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}
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return todo;
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}
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char *heap_end = 0;
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caddr_t _sbrk(int incr) {
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extern char heap_low;
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extern char heap_top;
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char *prev_heap_end;
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if (heap_end == 0) {
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heap_end = &heap_low;
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}
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prev_heap_end = heap_end;
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if (heap_end + incr > &heap_top) {
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/* Heap and stack collision */
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return (caddr_t)0;
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}
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heap_end += incr;
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return (caddr_t)prev_heap_end;
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}
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int _write(int file, char *ptr, int len) {
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int todo;
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for (todo = 0; todo < len; todo++) {
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UART_DR(UART0_ADDR) = *ptr++;
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}
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return len;
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}
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void _exit(int status) {
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#if defined(__arm__)
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__asm__ __volatile__ ("mov r0, #0x18; ldr r1, =#0x20026; svc 0x00123456");
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#endif
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}
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