Add linker scripts that target the scratchpad

Everything still defaults to the flash, but users can optionally select
the scratchpad.  Note that you have to be pretty careful about your
scratchpad programs, most of them won't fit.  For example, printf is too
big to fit in the scratchpad.

2 files changed, 161 insertions, 0 deletions

diff --git a/bsp/env/coreplexip-e31-arty/link.lds b/bsp/env/coreplexip-e31-arty/flash.lds
index 590c5b6..590c5b6 100644
--- a/bsp/env/coreplexip-e31-arty/link.lds
+++ b/bsp/env/coreplexip-e31-arty/flash.lds
diff --git a/bsp/env/coreplexip-e31-arty/scratchpad.lds b/bsp/env/coreplexip-e31-arty/scratchpad.lds
new file mode 100644
index 0000000..7887c13
--- /dev/null
+++ b/bsp/env/coreplexip-e31-arty/scratchpad.lds
@@ -0,0 +1,161 @@
+OUTPUT_ARCH( "riscv" )
+
+ENTRY( _start )
+
+MEMORY
+{
+  ram (wxa!ri) : ORIGIN = 0x80000000, LENGTH = 16K
+}
+
+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
+}