start implementing FW to control SPN HW

raven_spn/bsp/env/coreip-e2-arty/flash.lds

@@ -0,0 +1,161 @@
+OUTPUT_ARCH( "riscv" )
+
+ENTRY( _start )
+
+MEMORY
+{
+  flash (rxai!w) : ORIGIN = 0x40400000, LENGTH = 512M
+  ram (wxa!ri) : ORIGIN = 0x80000000, LENGTH = 64K
+}
+
+PHDRS
+{
+  flash PT_LOAD;
+  ram_init PT_LOAD;
+  ram PT_NULL;
+}
+
+SECTIONS
+{
+  __stack_size = DEFINED(__stack_size) ? __stack_size : 2K;
+
+  .init           :
+  {
+    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 .data.*)
+    *(.gnu.linkonce.d.*)
+    . = ALIGN(8);
+    PROVIDE( __global_pointer$ = . + 0x800 );
+    *(.sdata .sdata.*)
+    *(.gnu.linkonce.s.*)
+    . = ALIGN(8);
+    *(.srodata.cst16)
+    *(.srodata.cst8)
+    *(.srodata.cst4)
+    *(.srodata.cst2)
+    *(.srodata .srodata.*)
+  } >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);
+  PROVIDE( _end = . );
+  PROVIDE( end = . );
+
+  .stack ORIGIN(ram) + LENGTH(ram) - __stack_size :
+  {
+    PROVIDE( _heap_end = . );
+    . = __stack_size;
+    PROVIDE( _sp = . );
+  } >ram AT>ram :ram
+}

raven_spn/bsp/env/coreip-e2-arty/init.c

@@ -0,0 +1,98 @@
+//See LICENSE for license details.
+#include <stdint.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include "platform.h"
+#include "encoding.h"
+
+#define CPU_FREQ 32000000
+#define XSTR(x) #x
+#define STR(x) XSTR(x)
+
+extern int main(int argc, char** argv);
+
+unsigned long get_cpu_freq()
+{
+  return CPU_FREQ;
+}
+
+unsigned long get_timer_freq()
+{
+  return get_cpu_freq();
+}
+
+uint64_t get_timer_value()
+{
+#if __riscv_xlen == 32
+  while (1) {
+    uint32_t hi = read_csr(mcycleh);
+    uint32_t lo = read_csr(mcycle);
+    if (hi == read_csr(mcycleh))
+      return ((uint64_t)hi << 32) | lo;
+  }
+#else
+  return read_csr(mcycle);
+#endif
+}
+
+static void uart_init(size_t baud_rate)
+{
+  UART0_REG(UART_REG_DIV) = (get_cpu_freq() ) / baud_rate - 1;
+  UART0_REG(UART_REG_TXCTRL) |= UART_TXEN;
+}
+
+
+typedef void (*interrupt_function_ptr_t) (void);
+interrupt_function_ptr_t localISR[CLIC_NUM_INTERRUPTS] __attribute__((aligned(64)));
+
+
+void trap_entry(void) __attribute__((interrupt, aligned(64)));
+void trap_entry(void)
+{
+  unsigned long mcause = read_csr(mcause);
+  unsigned long mepc = read_csr(mepc);
+  if (mcause & MCAUSE_INT)  {
+    localISR[mcause & MCAUSE_CAUSE] ();
+  } else {
+    while(1); 
+  }
+}
+
+#ifdef CLIC_DIRECT
+#else
+void default_handler(void)__attribute__((interrupt));;
+#endif
+void default_handler(void)
+{
+  puts("default handler\n");
+  while(1);
+}
+
+void _init()
+{
+#ifndef NO_INIT
+  uart_init(115200);
+
+  puts("core freq at " STR(CPU_FREQ) " Hz\n");
+
+//initialize vector table
+  int i=0;
+  while(i<CLIC_NUM_INTERRUPTS)	{
+    localISR[i++] = default_handler;
+  }
+  
+  write_csr(mtvt, localISR);
+
+#ifdef CLIC_DIRECT
+  write_csr(mtvec, ((unsigned long)&trap_entry | MTVEC_CLIC));
+#else
+  write_csr(mtvec, ((unsigned long)&trap_entry | MTVEC_CLIC_VECT));
+#endif
+
+#endif
+}
+
+void _fini()
+{
+}

raven_spn/bsp/env/coreip-e2-arty/openocd.cfg

@@ -0,0 +1,31 @@
+# JTAG adapter setup
+adapter_khz     10000
+
+interface ftdi
+ftdi_device_desc "Olimex OpenOCD JTAG ARM-USB-TINY-H"
+ftdi_vid_pid 0x15ba 0x002a
+
+ftdi_layout_init 0x0808 0x0a1b
+ftdi_layout_signal nSRST -oe 0x0200
+#ftdi_layout_signal nTRST -data 0x0100 -oe 0x0100
+ftdi_layout_signal LED -data 0x0800
+
+set _CHIPNAME riscv
+jtag newtap $_CHIPNAME cpu -irlen 5 -expected-id 0x20000001
+
+set _TARGETNAME $_CHIPNAME.cpu
+
+target create $_TARGETNAME.0 riscv -chain-position $_TARGETNAME
+$_TARGETNAME.0 configure -work-area-phys 0x80000000 -work-area-size 10000 -work-area-backup 1
+
+# Un-comment these two flash lines if you have a SPI flash and want to write
+# it.
+flash bank spi0 fespi 0x40000000 0 0 0 $_TARGETNAME.0 0x20004000
+init
+if {[ info exists pulse_srst]} {
+  ftdi_set_signal nSRST 0
+  ftdi_set_signal nSRST z
+}
+halt
+#flash protect 0 64 last off
+echo "Ready for Remote Connections"

raven_spn/bsp/env/coreip-e2-arty/platform.h

@@ -0,0 +1,98 @@
+// See LICENSE for license details.
+
+#ifndef _SIFIVE_PLATFORM_H
+#define _SIFIVE_PLATFORM_H
+
+// Some things missing from the official encoding.h
+
+#if __riscv_xlen == 32
+#define MCAUSE_INT         0x80000000UL
+#define MCAUSE_CAUSE       0x000003FFUL
+#else
+#define MCAUSE_INT         0x8000000000000000UL
+#define MCAUSE_CAUSE       0x00000000000003FFUL
+#endif
+
+#define MTVEC_DIRECT       0X00
+#define MTVEC_VECTORED     0x01
+#define MTVEC_CLIC         0x02
+#define MTVEC_CLIC_VECT    0X03
+
+
+#include "sifive/const.h"
+#include "sifive/devices/gpio.h"
+#include "sifive/devices/clint.h"
+#include "sifive/devices/clic.h"
+#include "sifive/devices/pwm.h"
+#include "sifive/devices/spi.h"
+#include "sifive/devices/uart.h"
+
+/****************************************************************************
+ * Platform definitions
+ *****************************************************************************/
+
+// Memory map
+#define CLINT_CTRL_ADDR _AC(0x02000000,UL)
+#define CLIC_HART0_ADDR _AC(0x02800000,UL)
+#define GPIO_CTRL_ADDR _AC(0x20002000,UL)
+#define PWM0_CTRL_ADDR _AC(0x20005000,UL)
+#define RAM_MEM_ADDR _AC(0x80000000,UL)
+#define RAM_MEM_SIZE _AC(0x10000,UL)
+#define SPI0_CTRL_ADDR _AC(0x20004000,UL)
+#define SPI0_MEM_ADDR _AC(0x40000000,UL)
+#define SPI0_MEM_SIZE _AC(0x20000000,UL)
+#define TESTBENCH_MEM_ADDR _AC(0x20000000,UL)
+#define TESTBENCH_MEM_SIZE _AC(0x10000000,UL)
+//#define TRAPVEC_TABLE_CTRL_ADDR _AC(0x00001010,UL)
+#define UART0_CTRL_ADDR _AC(0x20000000,UL)
+
+// IOF masks
+
+// Interrupt numbers
+#define RESERVED_INT_BASE 0
+#define UART0_INT_BASE 1
+#define EXTERNAL_INT_BASE 2
+#define SPI0_INT_BASE 6
+#define GPIO_INT_BASE 7
+#define PWM0_INT_BASE 23
+
+// Helper functions
+#define _REG64(p, i) (*(volatile uint64_t *)((p) + (i)))
+#define _REG32(p, i) (*(volatile uint32_t *)((p) + (i)))
+#define _REG16(p, i) (*(volatile uint16_t *)((p) + (i)))
+#define SET_BITS(reg, mask, value) if ((value) == 0) { (reg) &= ~(mask); } else { (reg) |= (mask); }
+#define CLINT_REG(offset) _REG32(CLINT_CTRL_ADDR, offset)
+#define CLIC0_REG(offset) _REG32(CLIC_HART0_ADDR, offset)
+#define CLIC0_REG8(offset)   (*(volatile uint8_t *)((CLIC_HART0_ADDR) + (offset)))
+#define GPIO_REG(offset) _REG32(GPIO_CTRL_ADDR, offset)
+#define PWM0_REG(offset) _REG32(PWM0_CTRL_ADDR, offset)
+#define SPI0_REG(offset) _REG32(SPI0_CTRL_ADDR, offset)
+#define UART0_REG(offset) _REG32(UART0_CTRL_ADDR, offset)
+#define CLINT_REG(offset) _REG32(CLINT_CTRL_ADDR, offset)
+#define CLIC0_REG64(offset) _REG64(CLIC_HART0_ADDR, offset)
+#define GPIO_REG64(offset) _REG64(GPIO_CTRL_ADDR, offset)
+#define PWM0_REG64(offset) _REG64(PWM0_CTRL_ADDR, offset)
+#define SPI0_REG64(offset) _REG64(SPI0_CTRL_ADDR, offset)
+#define UART0_REG64(offset) _REG64(UART0_CTRL_ADDR, offset)
+
+// Misc
+
+#define NUM_GPIO 16
+
+#define CLIC_NUM_INTERRUPTS 28 + 16
+
+#ifdef E20
+   #define CLIC_CONFIG_BITS 2
+#else
+   #define CLIC_CONFIG_BITS 4
+#endif
+
+#define HAS_BOARD_BUTTONS
+
+#include "coreplexip-arty.h"
+
+unsigned long get_cpu_freq(void);
+unsigned long get_timer_freq(void);
+uint64_t get_timer_value(void);
+
+#endif /* _SIFIVE_PLATFORM_H */

raven_spn/bsp/env/coreip-e2-arty/settings.mk

@@ -0,0 +1,3 @@
+# Describes the CPU on this board to the rest of the SDK.
+RISCV_ARCH := rv32imac
+RISCV_ABI  := ilp32

raven_spn/bsp/env/coreip-e2-arty/tim-split.lds

@@ -0,0 +1,157 @@
+OUTPUT_ARCH( "riscv" )
+
+ENTRY( _start )
+
+MEMORY
+{
+  flash (rxai!w) : ORIGIN = 0x80008000, LENGTH = 32K
+  ram (wxa!ri) : ORIGIN = 0x80000000, LENGTH = 32K
+}
+
+PHDRS
+{
+  flash PT_LOAD;
+  ram_init PT_LOAD;
+  ram PT_NULL;
+}
+
+SECTIONS
+{
+  __stack_size = DEFINED(__stack_size) ? __stack_size : 1K;
+
+  .init           :
+  {
+    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 = .);
+
+  . = 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          :
+  {
+    *(.rdata)
+    *(.rodata .rodata.*)
+    *(.gnu.linkonce.r.*)
+    *(.data .data.*)
+    *(.gnu.linkonce.d.*)
+    . = ALIGN(8);
+    PROVIDE( __global_pointer$ = . + 0x800 );
+    *(.sdata .sdata.*)
+    *(.gnu.linkonce.s.*)
+    . = ALIGN(8);
+    *(.srodata.cst16)
+    *(.srodata.cst8)
+    *(.srodata.cst4)
+    *(.srodata.cst2)
+    *(.srodata .srodata.*)
+  } >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);
+  PROVIDE( _end = . );
+  PROVIDE( end = . );
+
+  .stack ORIGIN(ram) + LENGTH(ram) - __stack_size :
+  {
+    PROVIDE( _heap_end = . );
+    . = __stack_size;
+    PROVIDE( _sp = . );
+  } >ram AT>ram :ram
+}

raven_spn/bsp/env/coreip-e2-arty/tim.lds

@@ -0,0 +1,161 @@
+OUTPUT_ARCH( "riscv" )
+
+ENTRY( _start )
+
+MEMORY
+{
+  ram (wxa!ri) : ORIGIN = 0x80000000, LENGTH = 64K
+}
+
+PHDRS
+{
+  ram PT_LOAD;
+  ram_init PT_LOAD;
+  ram PT_NULL;
+}
+
+SECTIONS
+{
+  __stack_size = DEFINED(__stack_size) ? __stack_size : 1K;
+
+  .init           :
+  {
+    KEEP (*(SORT_NONE(.init)))
+  } >ram AT>ram :ram
+
+  .text           :
+  {
+    *(.text.unlikely .text.unlikely.*)
+    *(.text.startup .text.startup.*)
+    *(.text .text.*)
+    *(.gnu.linkonce.t.*)
+  } >ram AT>ram :ram
+
+  .fini           :
+  {
+    KEEP (*(SORT_NONE(.fini)))
+  } >ram AT>ram :ram
+
+  PROVIDE (__etext = .);
+  PROVIDE (_etext = .);
+  PROVIDE (etext = .);
+
+  .rodata         :
+  {
+    *(.rdata)
+    *(.rodata .rodata.*)
+    *(.gnu.linkonce.r.*)
+  } >ram AT>ram :ram
+
+  . = ALIGN(4);
+
+  .preinit_array  :
+  {
+    PROVIDE_HIDDEN (__preinit_array_start = .);
+    KEEP (*(.preinit_array))
+    PROVIDE_HIDDEN (__preinit_array_end = .);
+  } >ram AT>ram :ram
+
+  .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 = .);
+  } >ram AT>ram :ram
+
+  .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 = .);
+  } >ram AT>ram :ram
+
+  .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))
+  } >ram AT>ram :ram
+
+  .dtors          :
+  {
+    KEEP (*crtbegin.o(.dtors))
+    KEEP (*crtbegin?.o(.dtors))
+    KEEP (*(EXCLUDE_FILE (*crtend.o *crtend?.o ) .dtors))
+    KEEP (*(SORT(.dtors.*)))
+    KEEP (*(.dtors))
+  } >ram AT>ram :ram
+
+  .lalign         :
+  {
+    . = ALIGN(4);
+    PROVIDE( _data_lma = . );
+  } >ram AT>ram :ram
+
+  .dalign         :
+  {
+    . = ALIGN(4);
+    PROVIDE( _data = . );
+  } >ram AT>ram :ram_init
+
+  .data          :
+  {
+    *(.data .data.*)
+    *(.gnu.linkonce.d.*)
+    . = ALIGN(8);
+    PROVIDE( __global_pointer$ = . + 0x800 );
+    *(.sdata .sdata.*)
+    *(.gnu.linkonce.s.*)
+    . = ALIGN(8);
+    *(.srodata.cst16)
+    *(.srodata.cst8)
+    *(.srodata.cst4)
+    *(.srodata.cst2)
+    *(.srodata .srodata.*)
+  } >ram AT>ram :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);
+  PROVIDE( _end = . );
+  PROVIDE( end = . );
+
+  .stack :
+  {
+    . = ALIGN(8);
+    . += __stack_size;
+    PROVIDE( _sp = . );
+    PROVIDE( _heap_end = . );
+  } >ram AT>ram :ram
+}