adds TGC5L environment

bare-metal-bsp/env/TGC5L/.gitignore

@@ -0,0 +1 @@
+/*.o

bare-metal-bsp/env/TGC5L/init.c

@@ -0,0 +1,121 @@
+#include <stdint.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include "platform.h"
+#include "encoding.h"
+
+extern int main(int argc, char** argv);
+extern void trap_entry();
+
+static unsigned long mtime_lo(void)
+{
+    unsigned long ret;
+    __asm volatile("rdtime %0":"=r"(ret));
+    return ret;
+}
+
+
+#if __riscv_xlen==32
+
+static uint32_t mtime_hi(void)
+{
+    unsigned long ret;
+    __asm volatile("rdtimeh %0":"=r"(ret));
+    return ret;
+}
+
+uint64_t get_timer_value()
+{
+  while (1) {
+    uint32_t hi = mtime_hi();
+    uint32_t lo = mtime_lo();
+    if (hi == mtime_hi())
+      return ((uint64_t)hi << 32) | lo;
+  }
+}
+
+#elif __riscv_xlen==64
+
+uint64_t get_timer_value()
+{
+  return mtime_lo();
+}
+
+#endif
+
+unsigned long get_timer_freq()
+{
+  return 32768;
+}
+
+unsigned long get_cpu_freq()
+{
+  return 10000000;
+}
+
+void init_pll(void){
+
+}
+
+#ifdef USE_PLIC
+extern void handle_m_ext_interrupt();
+#endif
+
+#ifdef USE_M_TIME
+extern void handle_m_time_interrupt();
+#endif
+
+uintptr_t handle_trap(uintptr_t mcause, uintptr_t epc)
+{
+  if (0){
+#ifdef USE_PLIC
+    // External Machine-Level interrupt from PLIC
+  } else if ((mcause & MCAUSE_INT) && ((mcause & MCAUSE_CAUSE) == IRQ_M_EXT)) {
+    handle_m_ext_interrupt();
+#endif
+#ifdef USE_M_TIME
+    // External Machine-Level interrupt from PLIC
+  } else if ((mcause & MCAUSE_INT) && ((mcause & MCAUSE_CAUSE) == IRQ_M_TIMER)){
+    handle_m_time_interrupt();
+#endif
+  }
+  else {
+    char* result = "trap 0\n";
+    result[5]=(mcause&0xff)+'0';
+    //write(1, "trap\n", 5);
+    write(1, result, 7);
+    _exit(1 + mcause);
+  }
+  return epc;
+}
+
+void _init()
+{
+  
+#ifndef NO_INIT
+  init_pll();
+  printf("core freq at %d Hz\n", get_cpu_freq());
+  write_csr(mtvec, &trap_entry);
+  if (read_csr(misa) & (1 << ('F' - 'A'))) { // if F extension is present
+    write_csr(mstatus, MSTATUS_FS); // allow FPU instructions without trapping
+    write_csr(fcsr, 0); // initialize rounding mode, undefined at reset
+  }
+#endif
+  
+}
+
+void _fini()
+{
+}
+
+int is_uart_ready(int uart_id){
+    return 1;
+}
+int try_write_uart_char(int uart_id, char c){
+    *((char*)0x10000000) = c;
+    return 1;
+}
+void write_uart_char(int uart_id, char c){
+    *((char*)0x10000000) = c;
+}

bare-metal-bsp/env/TGC5L/link.lds

@@ -0,0 +1,174 @@
+OUTPUT_ARCH( "riscv" )
+
+ENTRY( _start )
+
+MEMORY
+{
+  flash (rxai!w) : ORIGIN = 0x80000000, LENGTH = 64k
+  ram (wxa!ri) :   ORIGIN = 0x80010000, LENGTH = 64k
+}
+
+PHDRS
+{
+  flash PT_LOAD;
+  ram_init PT_LOAD;
+  ram PT_NULL;
+}
+
+SECTIONS
+{
+  __stack_size = DEFINED(__stack_size) ? __stack_size : 2K;
+
+  .init ORIGIN(flash)        :
+  {
+    KEEP (*(SORT_NONE(.init)))
+  } >flash AT>flash :flash
+
+  .text           :
+  {
+    *(.text.unlikely .text.unlikely.*)
+    *(.text.startup .text.startup.*)
+    *(.text .text.*)
+    *(.gnu.linkonce.t.*)
+  } >flash AT>flash :flash
+
+  .fini           :
+  {
+    KEEP (*(SORT_NONE(.fini)))
+  } >flash AT>flash :flash
+
+  PROVIDE (__etext = .);
+  PROVIDE (_etext = .);
+  PROVIDE (etext = .);
+
+  .rodata         :
+  {
+    *(.rdata)
+    *(.rodata .rodata.*)
+    *(.gnu.linkonce.r.*)
+  } >flash AT>flash :flash
+
+  . = ALIGN(4);
+
+  .preinit_array  :
+  {
+    PROVIDE_HIDDEN (__preinit_array_start = .);
+    KEEP (*(.preinit_array))
+    PROVIDE_HIDDEN (__preinit_array_end = .);
+  } >flash AT>flash :flash
+
+  .init_array     :
+  {
+    PROVIDE_HIDDEN (__init_array_start = .);
+    KEEP (*(SORT_BY_INIT_PRIORITY(.init_array.*) SORT_BY_INIT_PRIORITY(.ctors.*)))
+    KEEP (*(.init_array EXCLUDE_FILE (*crtbegin.o *crtbegin?.o *crtend.o *crtend?.o ) .ctors))
+    PROVIDE_HIDDEN (__init_array_end = .);
+  } >flash AT>flash :flash
+
+  .fini_array     :
+  {
+    PROVIDE_HIDDEN (__fini_array_start = .);
+    KEEP (*(SORT_BY_INIT_PRIORITY(.fini_array.*) SORT_BY_INIT_PRIORITY(.dtors.*)))
+    KEEP (*(.fini_array EXCLUDE_FILE (*crtbegin.o *crtbegin?.o *crtend.o *crtend?.o ) .dtors))
+    PROVIDE_HIDDEN (__fini_array_end = .);
+  } >flash AT>flash :flash
+
+  .ctors          :
+  {
+    /* gcc uses crtbegin.o to find the start of
+       the constructors, so we make sure it is
+       first.  Because this is a wildcard, it
+       doesn't matter if the user does not
+       actually link against crtbegin.o; the
+       linker won't look for a file to match a
+       wildcard.  The wildcard also means that it
+       doesn't matter which directory crtbegin.o
+       is in.  */
+    KEEP (*crtbegin.o(.ctors))
+    KEEP (*crtbegin?.o(.ctors))
+    /* We don't want to include the .ctor section from
+       the crtend.o file until after the sorted ctors.
+       The .ctor section from the crtend file contains the
+       end of ctors marker and it must be last */
+    KEEP (*(EXCLUDE_FILE (*crtend.o *crtend?.o ) .ctors))
+    KEEP (*(SORT(.ctors.*)))
+    KEEP (*(.ctors))
+  } >flash AT>flash :flash
+
+  .dtors          :
+  {
+    KEEP (*crtbegin.o(.dtors))
+    KEEP (*crtbegin?.o(.dtors))
+    KEEP (*(EXCLUDE_FILE (*crtend.o *crtend?.o ) .dtors))
+    KEEP (*(SORT(.dtors.*)))
+    KEEP (*(.dtors))
+  } >flash AT>flash :flash
+
+  .lalign         :
+  {
+    . = ALIGN(4);
+    PROVIDE( _data_lma = . );
+  } >flash AT>flash :flash
+
+  .dalign         :
+  {
+    . = ALIGN(4);
+    PROVIDE( _data = . );
+  } >ram AT>flash :ram_init
+
+  .data          :
+  {
+    __DATA_BEGIN__ = .;
+    *(.data .data.*)
+    *(.gnu.linkonce.d.*)
+  } >ram AT>flash :ram_init
+
+  .srodata        :
+  {
+    PROVIDE( _gp = . + 0x800 );
+    *(.srodata.cst16)
+    *(.srodata.cst8)
+    *(.srodata.cst4)
+    *(.srodata.cst2)
+    *(.srodata .srodata.*)
+  } >ram AT>flash :ram_init
+
+  .sdata          :
+  {
+    __SDATA_BEGIN__ = .;
+    *(.sdata .sdata.*)
+    *(.gnu.linkonce.s.*)
+  } >ram AT>flash :ram_init
+
+  . = ALIGN(4);
+  PROVIDE( _edata = . );
+  PROVIDE( edata = . );
+
+  PROVIDE( _fbss = . );
+  PROVIDE( __bss_start = . );
+  .bss            :
+  {
+    *(.sbss*)
+    *(.gnu.linkonce.sb.*)
+    *(.bss .bss.*)
+    *(.gnu.linkonce.b.*)
+    *(COMMON)
+    . = ALIGN(4);
+  } >ram AT>ram :ram
+
+  . = ALIGN(8);
+  __BSS_END__ = .;
+  __global_pointer$ = MIN(__SDATA_BEGIN__ + 0x800,  MAX(__DATA_BEGIN__ + 0x800, __BSS_END__ - 0x800));
+  PROVIDE( _end = . );
+  PROVIDE( end = . );
+
+  .stack ORIGIN(ram) + LENGTH(ram) - __stack_size :
+  {
+    PROVIDE( _heap_end = . );
+    . = __stack_size;
+    PROVIDE( _sp = . );
+  } >ram AT>ram :ram
+
+  PROVIDE( tohost = 0xfffffff0 );
+  PROVIDE( fromhost = 0xfffffff8 );
+}

bare-metal-bsp/env/TGC5L/platform.h

@@ -0,0 +1,32 @@
+// See LICENSE for license details.
+
+#ifndef _ISS_PLATFORM_H
+#define _ISS_PLATFORM_H
+
+// Some things missing from the official encoding.h
+#define MCAUSE_INT         0x80000000
+#define MCAUSE_CAUSE       0x7FFFFFFF
+
+#include "rtl/const.h"
+/****************************************************************************
+ * Platform definitions
+ *****************************************************************************/
+
+#define MEM_BASE_ADDR _AC(0x00000000,UL)
+
+// Helper functions
+#define _REG32(p, i) (*(volatile uint32_t *) ((p) + (i)))
+#define _REG32P(p, i) ((volatile uint32_t *) ((p) + (i)))
+
+// Misc
+
+#include <stdint.h>
+
+void init_pll(void);
+unsigned long get_cpu_freq(void);
+unsigned long get_timer_freq(void);
+uint64_t get_timer_value(void);
+int is_uart_ready(int uart_id);
+int try_write_uart_char(int uart_id, char);
+void write_uart_char(int uart_id, char);
+#endif /* _ISS_PLATFORM_H */