add support for STM32F746G-DISCO device

Tested with toolbox / simpleinit as userland.
FDPIC/FLAT support both successfully tested.

No LCD or Ethernet support.

5 files changed, 710 insertions, 0 deletions

diff --git a/toolchain/elf2flt/patches/v2021.08/0001-elf2flt-handle-binutils-2.34.patch b/toolchain/elf2flt/patches/v2021.08/0001-elf2flt-handle-binutils-2.34.patch
new file mode 100644
index 000000000..4aa473c24
--- /dev/null
+++ b/toolchain/elf2flt/patches/v2021.08/0001-elf2flt-handle-binutils-2.34.patch
@@ -0,0 +1,377 @@
+From d78acba6510527aaa01a41eaf4c931f7a57e5f44 Mon Sep 17 00:00:00 2001
+From: Romain Naour <romain.naour@smile.fr>
+Date: Wed, 5 Feb 2020 10:31:32 +0100
+Subject: [PATCH] elf2flt: handle binutils >= 2.34
+
+The latest Binutils release (2.34) is not compatible with elf2flt due
+to a change in bfd_section_* macros [1]. The issue has been reported
+to the Binutils mailing list but Alan Modra recommend to bundle
+libbfd library sources into each projects using it [2]. That's
+because the API is not stable over the time without any backward
+compatibility guaranties.
+
+On the other hand, the elf2flt tools needs to support modified
+version of binutils for specific arch/target [3].
+
+Add two tests in the configure script to detect this API change
+in order to support binutils < 2.34 and binutils >= 2.34.
+
+Upstream status: [4]
+
+[1] https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=fd3619828e94a24a92cddec42cbc0ab33352eeb4
+[2] https://sourceware.org/ml/binutils/2020-02/msg00044.html
+[3] https://github.com/uclinux-dev/elf2flt/issues/14
+[4] https://github.com/uclinux-dev/elf2flt/pull/15
+
+Signed-off-by: Romain Naour <romain.naour@smile.fr>
+---
+ configure.ac | 16 +++++++++++
+ elf2flt.c    | 81 +++++++++++++++++++++++++++++-----------------------
+ 2 files changed, 61 insertions(+), 36 deletions(-)
+
+diff --git a/configure.ac b/configure.ac
+index b7db2cb..fdc0876 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -229,6 +229,22 @@ AC_CHECK_FUNCS([ \
+ 	strsignal \
+ ])
+ 
++dnl Various bfd section macros and functions like bfd_section_size() have been
++dnl modified starting with binutils >= 2.34.
++dnl Check if the prototypes take a bfd argument.
++if test "$binutils_build_dir" != "NONE"; then
++    CFLAGS="-I$binutils_include_dir -I$bfd_include_dir $CFLAGS"
++fi
++
++AC_TRY_COMPILE([#include <bfd.h>],
++ [const asection *sec; bfd_section_size(sec);],
++ bfd_section_api_takes_bfd=no,
++ bfd_section_api_takes_bfd=yes)
++if test "$bfd_section_api_takes_bfd" = "yes" ; then
++  AC_DEFINE(HAVE_BFD_SECTION_API_TAKES_BFD, 1,
++   [define to 1 for binutils < 2.34])
++fi
++
+ if test "$GCC" = yes ; then
+ 	CFLAGS="-Wall $CFLAGS"
+ 	if test "$werror" = 1 ; then
+diff --git a/elf2flt.c b/elf2flt.c
+index 7ac0617..ea6b5a1 100644
+--- a/elf2flt.c
++++ b/elf2flt.c
+@@ -149,6 +149,17 @@ const char *elf2flt_progname;
+ #define O_BINARY 0
+ #endif
+ 
++/*
++ * The bfd parameter isn't actually used by any of the bfd_section funcs and
++ * have been removed since binutils 2.34.
++ */
++#ifdef HAVE_BFD_SECTION_API_TAKES_BFD
++#define elf2flt_bfd_section_size(s) bfd_section_size(NULL, s)
++#define elf2flt_bfd_section_vma(s)  bfd_section_vma(NULL, s)
++#else
++#define elf2flt_bfd_section_size(s) bfd_section_size(s)
++#define elf2flt_bfd_section_vma(s)  bfd_section_vma(s)
++#endif
+ 
+ /* Extra output when running.  */
+ static int verbose = 0;
+@@ -323,10 +334,8 @@ compare_relocs (const void *pa, const void *pb)
+ 	else if (!rb->sym_ptr_ptr || !*rb->sym_ptr_ptr)
+ 		return 1;
+ 
+-	a_vma = bfd_section_vma(compare_relocs_bfd,
+-				(*(ra->sym_ptr_ptr))->section);
+-	b_vma = bfd_section_vma(compare_relocs_bfd,
+-				(*(rb->sym_ptr_ptr))->section);
++	a_vma = elf2flt_bfd_section_vma((*(ra->sym_ptr_ptr))->section);
++	b_vma = elf2flt_bfd_section_vma((*(rb->sym_ptr_ptr))->section);
+ 	va = (*(ra->sym_ptr_ptr))->value + a_vma + ra->addend;
+ 	vb = (*(rb->sym_ptr_ptr))->value + b_vma + rb->addend;
+ 	return va - vb;
+@@ -403,7 +412,7 @@ output_relocs (
+   }
+ 
+   for (a = abs_bfd->sections; (a != (asection *) NULL); a = a->next) {
+-  	section_vma = bfd_section_vma(abs_bfd, a);
++	section_vma = elf2flt_bfd_section_vma(a);
+ 
+ 	if (verbose)
+ 		printf("SECTION: %s [%p]: flags=0x%x vma=0x%"PRIx32"\n",
+@@ -443,7 +452,7 @@ output_relocs (
+ 	  continue;
+ 	if (verbose)
+ 	  printf(" RELOCS: %s [%p]: flags=0x%x vma=0x%"BFD_VMA_FMT"x\n",
+-			r->name, r, r->flags, bfd_section_vma(abs_bfd, r));
++			r->name, r, r->flags, elf2flt_bfd_section_vma(r));
+   	if ((r->flags & SEC_RELOC) == 0)
+   	  continue;
+ 	relsize = bfd_get_reloc_upper_bound(rel_bfd, r);
+@@ -695,7 +704,7 @@ output_relocs (
+ 				case R_BFIN_RIMM16:
+ 				case R_BFIN_LUIMM16:
+ 				case R_BFIN_HUIMM16:
+-				    sym_vma = bfd_section_vma(abs_bfd, sym_section);
++				    sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 				    sym_addr += sym_vma + q->addend;
+ 
+ 				    if (weak_und_symbol(sym_section->name, (*(q->sym_ptr_ptr))))
+@@ -728,7 +737,7 @@ output_relocs (
+ 				    break;
+ 
+ 				case R_BFIN_BYTE4_DATA:
+-				    sym_vma = bfd_section_vma(abs_bfd, sym_section);
++				    sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 				    sym_addr += sym_vma + q->addend;
+ 
+ 				    if (weak_und_symbol (sym_section->name, (*(q->sym_ptr_ptr))))
+@@ -886,7 +895,7 @@ output_relocs (
+ #if defined(TARGET_m68k)
+ 				case R_68K_32:
+ 					relocation_needed = 1;
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					break;
+ 				case R_68K_PC16:
+@@ -911,7 +920,7 @@ output_relocs (
+ 							q->address, sym_addr,
+ 							(*p)->howto->rightshift,
+ 							*(uint32_t *)r_mem);
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					break;
+ 				case R_ARM_GOT32:
+@@ -939,7 +948,7 @@ output_relocs (
+ #ifdef TARGET_v850
+ 				case R_V850_ABS32:
+ 					relocation_needed = 1;
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					break;
+ 				case R_V850_ZDA_16_16_OFFSET:
+@@ -961,7 +970,7 @@ output_relocs (
+ 					sym_addr = (*(q->sym_ptr_ptr))->value;
+ 					q->address -= 1;
+ 					r_mem -= 1; /* tracks q->address */
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					sym_addr |= (*(unsigned char *)r_mem<<24);
+ 					break;
+@@ -974,7 +983,7 @@ output_relocs (
+ 					/* Absolute symbol done not relocation */
+ 					relocation_needed = !bfd_is_abs_section(sym_section);
+ 					sym_addr = (*(q->sym_ptr_ptr))->value;
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					break;
+ 				case R_H8_DIR32:
+@@ -987,7 +996,7 @@ output_relocs (
+ 					}
+ 					relocation_needed = 1;
+ 					sym_addr = (*(q->sym_ptr_ptr))->value;
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					break;
+ 				case R_H8_PCREL16:
+@@ -1013,7 +1022,7 @@ output_relocs (
+ #ifdef TARGET_microblaze
+ 				case R_MICROBLAZE_64:
+ 					/* work out the relocation */
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					/* Write relocated pointer back */
+ 					r_mem[2] = (sym_addr >> 24) & 0xff;
+@@ -1027,7 +1036,7 @@ output_relocs (
+ 					pflags = 0x80000000;
+ 					break;
+ 				case R_MICROBLAZE_32:
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					relocation_needed = 1;
+ 					break;
+@@ -1059,7 +1068,7 @@ output_relocs (
+ 				case R_NIOS2_BFD_RELOC_32:
+ 					relocation_needed = 1;
+ 					pflags = (FLAT_NIOS2_R_32 << 28);
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					/* modify target, in target order */
+ 					*(unsigned long *)r_mem = htoniosl(sym_addr);
+@@ -1069,7 +1078,7 @@ output_relocs (
+ 					unsigned long exist_val;
+ 					relocation_needed = 1;
+ 					pflags = (FLAT_NIOS2_R_CALL26 << 28);
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 
+ 					/* modify target, in target order */
+@@ -1100,7 +1109,7 @@ output_relocs (
+ 								? FLAT_NIOS2_R_HIADJ_LO : FLAT_NIOS2_R_HI_LO;
+ 							pflags <<= 28;
+ 
+-							sym_vma = bfd_section_vma(abs_bfd, sym_section);
++							sym_vma = elf2flt_bfd_section_vma(abs_bfd, sym_section);
+ 							sym_addr += sym_vma + q->addend;
+ 
+ 							/* modify high 16 bits, in target order */
+@@ -1133,7 +1142,7 @@ output_relocs (
+ 						goto NIOS2_RELOC_ERR;
+ 					}
+ 					/* _gp holds a absolute value, otherwise the ld cannot generate correct code */
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					//printf("sym=%x, %d, _gp=%x, %d\n", sym_addr+sym_vma, sym_addr+sym_vma, gp, gp);
+ 					sym_addr += sym_vma + q->addend;
+ 					sym_addr -= gp;
+@@ -1214,7 +1223,7 @@ NIOS2_RELOC_ERR:
+ 				case R_SPARC_32:
+ 				case R_SPARC_UA32:
+ 					relocation_needed = 1;
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					break;
+ 				case R_SPARC_PC22:
+@@ -1233,7 +1242,7 @@ NIOS2_RELOC_ERR:
+ 				case R_SPARC_HI22:
+ 					relocation_needed = 1;
+ 					pflags = 0x80000000;
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					sym_addr |= (
+ 						htonl(*(uint32_t *)r_mem)
+@@ -1243,7 +1252,7 @@ NIOS2_RELOC_ERR:
+ 				case R_SPARC_LO10:
+ 					relocation_needed = 1;
+ 					pflags = 0x40000000;
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					sym_addr &= 0x000003ff;
+ 					sym_addr |= (
+@@ -1257,7 +1266,7 @@ NIOS2_RELOC_ERR:
+ #ifdef TARGET_sh
+ 				case R_SH_DIR32:
+ 					relocation_needed = 1;
+-					sym_vma = bfd_section_vma(abs_bfd, sym_section);
++					sym_vma = elf2flt_bfd_section_vma(sym_section);
+ 					sym_addr += sym_vma + q->addend;
+ 					break;
+ 				case R_SH_REL32:
+@@ -1289,7 +1298,7 @@ NIOS2_RELOC_ERR:
+ 				case R_E1_CONST31:
+ 						relocation_needed = 1;
+ 						DBG_E1("Handling Reloc <CONST31>\n");
+-						sec_vma = bfd_section_vma(abs_bfd, sym_section);
++						sec_vma = elf2flt_bfd_section_vma(sym_section);
+ 						DBG_E1("sec_vma : [0x%x], sym_addr : [0x%x], q->address : [0x%x]\n",
+ 										sec_vma, sym_addr, q->address);
+ 						sym_addr = sec_vma + sym_addr;
+@@ -1304,7 +1313,7 @@ NIOS2_RELOC_ERR:
+ 						relocation_needed = 0;
+ 						DBG_E1("Handling Reloc <CONST31_PCREL>\n");
+ 						DBG_E1("DONT RELOCATE AT LOADING\n");
+-						sec_vma = bfd_section_vma(abs_bfd, sym_section);
++						sec_vma = elf2flt_bfd_section_vma(sym_section);
+ 						DBG_E1("sec_vma : [0x%x], sym_addr : [0x%x], q->address : [0x%x]\n",
+ 										sec_vma, sym_addr, q->address);
+ 						sym_addr =  sec_vma + sym_addr;
+@@ -1331,7 +1340,7 @@ NIOS2_RELOC_ERR:
+ 						relocation_needed = 0;
+ 						DBG_E1("Handling Reloc <DIS29W_PCREL>\n");
+ 						DBG_E1("DONT RELOCATE AT LOADING\n");
+-						sec_vma = bfd_section_vma(abs_bfd, sym_section);
++						sec_vma = elf2flt_bfd_section_vma(sym_section);
+ 						DBG_E1("sec_vma : [0x%x], sym_addr : [0x%x], q->address : [0x%x]\n",
+ 										sec_vma, sym_addr, q->address);
+ 						sym_addr =  sec_vma + sym_addr;
+@@ -1364,7 +1373,7 @@ NIOS2_RELOC_ERR:
+ 						DBG_E1("Handling Reloc <DIS29B>\n");
+ DIS29_RELOCATION:
+ 						relocation_needed = 1;
+-						sec_vma = bfd_section_vma(abs_bfd, sym_section);
++						sec_vma = elf2flt_bfd_section_vma(sym_section);
+ 						DBG_E1("sec_vma : [0x%x], sym_addr : [0x%08x]\n",
+ 										sec_vma, sym_addr);
+ 						sym_addr =  sec_vma + sym_addr;
+@@ -1381,7 +1390,7 @@ DIS29_RELOCATION:
+ 						relocation_needed = 0;
+ 						DBG_E1("Handling Reloc <IMM32_PCREL>\n");
+ 						DBG_E1("DONT RELOCATE AT LOADING\n");
+-						sec_vma = bfd_section_vma(abs_bfd, sym_section);
++						sec_vma = elf2flt_bfd_section_vma(sym_section);
+ 						DBG_E1("sec_vma : [0x%x], sym_addr : [0x%x]\n",
+ 										sec_vma, sym_addr);
+ 						sym_addr =  sec_vma + sym_addr;
+@@ -1407,7 +1416,7 @@ DIS29_RELOCATION:
+ 				case R_E1_IMM32:
+ 						relocation_needed = 1;
+ 						DBG_E1("Handling Reloc <IMM32>\n");
+-						sec_vma = bfd_section_vma(abs_bfd, sym_section);
++						sec_vma = elf2flt_bfd_section_vma(sym_section);
+ 						DBG_E1("sec_vma : [0x%x], sym_addr : [0x%x]\n",
+ 										sec_vma, sym_addr);
+ 						sym_addr =  sec_vma + sym_addr;
+@@ -1423,7 +1432,7 @@ DIS29_RELOCATION:
+ 				case R_E1_WORD:
+ 						relocation_needed = 1;
+ 						DBG_E1("Handling Reloc <WORD>\n");
+-						sec_vma = bfd_section_vma(abs_bfd, sym_section);
++						sec_vma = elf2flt_bfd_section_vma(sym_section);
+ 						DBG_E1("sec_vma : [0x%x], sym_addr : [0x%x]\n",
+ 										sec_vma, sym_addr);
+ 						sym_addr =  sec_vma + sym_addr;
+@@ -1450,7 +1459,7 @@ DIS29_RELOCATION:
+ 			}
+ 
+ 			sprintf(&addstr[0], "+0x%lx", sym_addr - (*(q->sym_ptr_ptr))->value -
+-					 bfd_section_vma(abs_bfd, sym_section));
++					 elf2flt_bfd_section_vma(sym_section));
+ 
+ 
+ 			/*
+@@ -1890,8 +1899,8 @@ int main(int argc, char *argv[])
+     } else
+       continue;
+ 
+-    sec_size = bfd_section_size(abs_bfd, s);
+-    sec_vma  = bfd_section_vma(abs_bfd, s);
++    sec_size = elf2flt_bfd_section_size(s);
++    sec_vma  = elf2flt_bfd_section_vma(s);
+ 
+     if (sec_vma < *vma) {
+       if (*len > 0)
+@@ -1920,7 +1929,7 @@ int main(int argc, char *argv[])
+                     (SEC_DATA | SEC_READONLY | SEC_RELOC)))
+       if (!bfd_get_section_contents(abs_bfd, s,
+ 				   text + (s->vma - text_vma), 0,
+-				   bfd_section_size(abs_bfd, s)))
++				   elf2flt_bfd_section_size(s)))
+       {
+ 	fatal("read error section %s", s->name);
+       }
+@@ -1950,7 +1959,7 @@ int main(int argc, char *argv[])
+                     (SEC_READONLY | SEC_RELOC)))
+       if (!bfd_get_section_contents(abs_bfd, s,
+ 				   data + (s->vma - data_vma), 0,
+-				   bfd_section_size(abs_bfd, s)))
++				   elf2flt_bfd_section_size(s)))
+       {
+ 	fatal("read error section %s", s->name);
+       }
+-- 
+2.35.1
+
diff --git a/toolchain/elf2flt/patches/v2021.08/0002-elf2flt.ld-reinstate-32-byte-alignment-for-.data-sec.patch b/toolchain/elf2flt/patches/v2021.08/0002-elf2flt.ld-reinstate-32-byte-alignment-for-.data-sec.patch
new file mode 100644
index 000000000..4df3ea592
--- /dev/null
+++ b/toolchain/elf2flt/patches/v2021.08/0002-elf2flt.ld-reinstate-32-byte-alignment-for-.data-sec.patch
@@ -0,0 +1,81 @@
+From 85ba5664eb368eb1cbd2c30b7cd574acd75edd4c Mon Sep 17 00:00:00 2001
+From: Niklas Cassel <niklas.cassel@wdc.com>
+Date: Mon, 4 Apr 2022 15:30:24 +0200
+Subject: [PATCH] elf2flt.ld: reinstate 32 byte alignment for .data section
+
+Commit 8a3e74446fe7 ("allow to build arm flat binaries") moved the
+following commands:
+	. = ALIGN(0x20) ;
+	@SYMBOL_PREFIX@_etext = . ;
+from the .text section to the top level in the SECTIONS node.
+
+The .text output section is being directed to a memory region using the
+"> flatmem :text" output section attribute. Commands in the top level in
+the SECTIONS node are not.
+
+This means that the ALIGN() command is no longer being appended to the
+flatmem memory region, it will simply update the Location Counter.
+
+The heuristic for placing an output section is described here:
+https://sourceware.org/binutils/docs-2.38/ld.html#Output-Section-Address
+
+"If an output memory region is set for the section then it is added to this
+region and its address will be the next free address in that region."
+
+Since the .data section is being directed to the same memory region as the
+.text section, this means that the Location Counter is not used when
+assigning an address to the .data output section, it will simply use the
+next free address.
+
+No longer directing these commands to the flatmem memory region means that
+the .data output section is no longer aligned to a 32 byte boundary.
+
+Before commit 8a3e74446fe7 ("allow to build arm flat binaries"):
+$ readelf -S busybox_unstripped.gdb | grep data
+  [ 3] .data             PROGBITS         0000000000035ac0  00036ac0
+$ readelf -s busybox_unstripped.gdb | grep _etext
+ 19286: 0000000000035ac0     0 NOTYPE  GLOBAL DEFAULT    1 _etext
+
+After commit 8a3e74446fe7 ("allow to build arm flat binaries"):
+$ readelf -S busybox_unstripped.gdb | grep data
+  [ 3] .data             PROGBITS         0000000000035ab0  00036ab0
+$ readelf -s busybox_unstripped.gdb | grep _etext
+ 19287: 0000000000035ac0     0 NOTYPE  GLOBAL DEFAULT    3 _etext
+
+The .data output section has to be aligned to a 32 byte boundary, see the
+FLAT_DATA_ALIGN 0x20 macro and its usage in fs/binfmt_flat.c:
+https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/fs/binfmt_flat.c?h=v5.17#n59
+
+Readd an explicit ALIGN attribute on the .data section itself, since the
+linker will obey this attribute regardless if being directed to a memory
+region or not. Also remove the ALIGN() command before the .data section,
+since this misleads the reader to think that the Location Counter is used
+when assigning an address to the .data section, when it actually is not.
+
+Fixes: 8a3e74446fe7 ("allow to build arm flat binaries")
+Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
+---
+ elf2flt.ld.in | 5 +----
+ 1 file changed, 1 insertion(+), 4 deletions(-)
+
+diff --git a/elf2flt.ld.in b/elf2flt.ld.in
+index 0df999d..e5aea14 100644
+--- a/elf2flt.ld.in
++++ b/elf2flt.ld.in
+@@ -94,12 +94,9 @@ W_RODAT:	*(.gnu.linkonce.r*)
+ 		*(.ARM.exidx* .gnu.linkonce.armexidx.*)
+ 	} > flatmem
+ 	@SYMBOL_PREFIX@__exidx_end = .;
+-
+-	. = ALIGN(0x20) ;
+ 	@SYMBOL_PREFIX@_etext = . ;
+ 
+-	.data : {
+-		. = ALIGN(0x4) ;
++	.data ALIGN(0x20): {
+ 		@SYMBOL_PREFIX@_sdata = . ;
+ 		@SYMBOL_PREFIX@__data_start = . ;
+ 		@SYMBOL_PREFIX@data_start = . ;
+-- 
+2.35.1
+
diff --git a/toolchain/elf2flt/patches/v2021.08/0003-elf2flt-add-riscv-64-bits-support.patch b/toolchain/elf2flt/patches/v2021.08/0003-elf2flt-add-riscv-64-bits-support.patch
new file mode 100644
index 000000000..15c191c83
--- /dev/null
+++ b/toolchain/elf2flt/patches/v2021.08/0003-elf2flt-add-riscv-64-bits-support.patch
@@ -0,0 +1,103 @@
+From 3f1f323feb5cf25d8c80861991d0360784f4d2e6 Mon Sep 17 00:00:00 2001
+From: Damien Le Moal <damien.lemoal@wdc.com>
+Date: Wed, 9 Sep 2020 17:31:33 +0900
+Subject: [PATCH] elf2flt: add riscv 64-bits support
+
+Add support for riscv 64bits ISA by defining the relocation types
+R_RISCV_32_PCREL, R_RISCV_ADD32, R_RISCV_SUB32, R_RISCV_32 and
+R_RISCV_64. riscv64 support also needs the __global_pointer$ symbol to
+be defined right after the relocation tables in the data section. To
+define this symbol, the "RISCV_GP" line prefix is added. The "RISCV_GP"
+string is removed if the target CPU type is riscv64 and the definition
+line is dropped for other CPU types.
+
+With these changes, buildroot and busybox build and run on riscv NOMMU
+systems with Linux kernel including patch 6045ab5fea4c
+("binfmt_flat: do not stop relocating GOT entries prematurely on riscv")
+fixing the binfmt_flat loader. Tested on QEMU and Canaan Kendryte K210
+boards.
+
+This patch is based on earlier work by Christoph Hellwig <hch@lst.de>.
+
+Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
+---
+ elf2flt.c     | 16 ++++++++++++++++
+ elf2flt.ld.in |  1 +
+ ld-elf2flt.c  |  8 ++++++++
+ 3 files changed, 25 insertions(+)
+
+diff --git a/elf2flt.c b/elf2flt.c
+index da25e93..a03ea3a 100644
+--- a/elf2flt.c
++++ b/elf2flt.c
+@@ -81,6 +81,8 @@ const char *elf2flt_progname;
+ #include <elf/v850.h>
+ #elif defined(TARGET_xtensa)
+ #include <elf/xtensa.h>
++#elif defined(TARGET_riscv64)
++#include <elf/riscv.h>
+ #endif
+ 
+ #if defined(__MINGW32__)
+@@ -123,6 +125,8 @@ const char *elf2flt_progname;
+ #define ARCH	"nios2"
+ #elif defined(TARGET_xtensa)
+ #define ARCH	"xtensa"
++#elif defined(TARGET_riscv64)
++#define ARCH	"riscv64"
+ #else
+ #error "Don't know how to support your CPU architecture??"
+ #endif
+@@ -812,6 +816,18 @@ output_relocs (
+ 					goto good_32bit_resolved_reloc;
+ 				default:
+ 					goto bad_resolved_reloc;
++#elif defined(TARGET_riscv64)
++				case R_RISCV_32_PCREL:
++				case R_RISCV_ADD32:
++				case R_RISCV_ADD64:
++				case R_RISCV_SUB32:
++				case R_RISCV_SUB64:
++					continue;
++				case R_RISCV_32:
++				case R_RISCV_64:
++					goto good_32bit_resolved_reloc;
++				default:
++					goto bad_resolved_reloc;
+ #else
+ 				default:
+ 					/* The default is to assume that the
+diff --git a/elf2flt.ld.in b/elf2flt.ld.in
+index e5aea14..950849e 100644
+--- a/elf2flt.ld.in
++++ b/elf2flt.ld.in
+@@ -106,6 +106,7 @@ W_RODAT:	*(.gnu.linkonce.r*)
+ 		. = ALIGN(0x20) ;
+ 		LONG(-1)
+ 		. = ALIGN(0x20) ;
++RISCV_GP:	__global_pointer$ = . + 0x800 ;
+ R_RODAT:	*(.rodata)
+ R_RODAT:	*(.rodata1)
+ R_RODAT:	*(.rodata.*)
+diff --git a/ld-elf2flt.c b/ld-elf2flt.c
+index 7cb02d5..75ee1bb 100644
+--- a/ld-elf2flt.c
++++ b/ld-elf2flt.c
+@@ -324,6 +324,14 @@ static int do_final_link(void)
+ 		append_option(&other_options, concat(got_offset, "=", buf, NULL));
+ 	}
+ 
++	/* riscv adds a global pointer symbol to the linker file with the
++	   "RISCV_GP:" prefix. Remove the prefix for riscv64 architecture and
++	   the entire line for other architectures. */
++	if (streq(TARGET_CPU, "riscv64"))
++		append_sed(&sed, "^RISCV_GP:", "");
++	else
++		append_sed(&sed, "^RISCV_GP:", NULL);
++
+ 	/* Locate the default linker script, if we don't have one provided. */
+ 	if (!linker_script)
+ 		linker_script = concat(ldscriptpath, "/elf2flt.ld", NULL);
+-- 
+2.36.1
+
diff --git a/toolchain/elf2flt/patches/v2021.08/0004-elf2flt-create-a-common-helper-function.patch b/toolchain/elf2flt/patches/v2021.08/0004-elf2flt-create-a-common-helper-function.patch
new file mode 100644
index 000000000..6fee99d45
--- /dev/null
+++ b/toolchain/elf2flt/patches/v2021.08/0004-elf2flt-create-a-common-helper-function.patch
@@ -0,0 +1,76 @@
+From 37e1e0ace8ccebf54ec2f5522bfc1f9db86946ad Mon Sep 17 00:00:00 2001
+From: Niklas Cassel <niklas.cassel@wdc.com>
+Date: Tue, 9 Aug 2022 12:13:50 +0200
+Subject: [PATCH] elf2flt: create a common helper function
+
+In order to make the code more maintainable,
+move duplicated code to a common helper function.
+
+No functional change intended.
+
+Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
+---
+ elf2flt.c | 19 +++++++++++--------
+ 1 file changed, 11 insertions(+), 8 deletions(-)
+
+diff --git a/elf2flt.c b/elf2flt.c
+index 669591e..9c32f9a 100644
+--- a/elf2flt.c
++++ b/elf2flt.c
+@@ -337,6 +337,13 @@ compare_relocs (const void *pa, const void *pb)
+ }
+ #endif
+ 
++static bool
++ro_reloc_data_section_should_be_in_text(asection *s)
++{
++  return (s->flags & (SEC_DATA | SEC_READONLY | SEC_RELOC)) ==
++	  (SEC_DATA | SEC_READONLY | SEC_RELOC);
++}
++
+ static uint32_t *
+ output_relocs (
+   bfd *abs_bfd,
+@@ -428,8 +435,7 @@ output_relocs (
+ 	 */
+ 	if ((!pic_with_got || ALWAYS_RELOC_TEXT) &&
+ 	    ((a->flags & SEC_CODE) ||
+-	    ((a->flags & (SEC_DATA | SEC_READONLY | SEC_RELOC)) ==
+-		         (SEC_DATA | SEC_READONLY | SEC_RELOC))))
++	     ro_reloc_data_section_should_be_in_text(a)))
+ 		sectionp = text + (a->vma - text_vma);
+ 	else if (a->flags & SEC_DATA)
+ 		sectionp = data + (a->vma - data_vma);
+@@ -1893,8 +1899,7 @@ int main(int argc, char *argv[])
+     bfd_vma sec_vma;
+ 
+     if ((s->flags & SEC_CODE) ||
+-       ((s->flags & (SEC_DATA | SEC_READONLY | SEC_RELOC)) ==
+-                    (SEC_DATA | SEC_READONLY | SEC_RELOC))) {
++	ro_reloc_data_section_should_be_in_text(s)) {
+       vma = &text_vma;
+       len = &text_len;
+     } else if (s->flags & SEC_DATA) {
+@@ -1932,8 +1937,7 @@ int main(int argc, char *argv[])
+    * data sections.*/
+   for (s = abs_bfd->sections; s != NULL; s = s->next)
+     if ((s->flags & SEC_CODE) ||
+-       ((s->flags & (SEC_DATA | SEC_READONLY | SEC_RELOC)) ==
+-                    (SEC_DATA | SEC_READONLY | SEC_RELOC)))
++	ro_reloc_data_section_should_be_in_text(s))
+       if (!bfd_get_section_contents(abs_bfd, s,
+ 				   text + (s->vma - text_vma), 0,
+ 				   bfd_section_size(abs_bfd, s)))
+@@ -1962,8 +1966,7 @@ int main(int argc, char *argv[])
+    * data sections already included in the text output section.*/
+   for (s = abs_bfd->sections; s != NULL; s = s->next)
+     if ((s->flags & SEC_DATA) &&
+-       ((s->flags & (SEC_READONLY | SEC_RELOC)) !=
+-                    (SEC_READONLY | SEC_RELOC)))
++	!ro_reloc_data_section_should_be_in_text(s))
+       if (!bfd_get_section_contents(abs_bfd, s,
+ 				   data + (s->vma - data_vma), 0,
+ 				   bfd_section_size(abs_bfd, s)))
+-- 
+2.37.1
+
diff --git a/toolchain/elf2flt/patches/v2021.08/0005-elf2flt-fix-fatal-error-regression-on-m68k-xtensa-ri.patch b/toolchain/elf2flt/patches/v2021.08/0005-elf2flt-fix-fatal-error-regression-on-m68k-xtensa-ri.patch
new file mode 100644
index 000000000..278709cb1
--- /dev/null
+++ b/toolchain/elf2flt/patches/v2021.08/0005-elf2flt-fix-fatal-error-regression-on-m68k-xtensa-ri.patch
@@ -0,0 +1,73 @@
+From 65ac5f9e69cfb989d970da74c41e478774d29be5 Mon Sep 17 00:00:00 2001
+From: Niklas Cassel <niklas.cassel@wdc.com>
+Date: Tue, 9 Aug 2022 21:06:05 +0200
+Subject: [PATCH] elf2flt: fix fatal error regression on m68k, xtensa,
+ riscv64
+
+Commit ba379d08bb78 ("elf2flt: fix for segfault on some ARM ELFs")
+changed the condition of which input sections that should be included
+in the .text output section from:
+((a->flags & (SEC_DATA | SEC_READONLY)) == (SEC_DATA | SEC_READONLY))
+to:
+((a->flags & (SEC_DATA | SEC_READONLY | SEC_RELOC)) ==
+(SEC_DATA | SEC_READONLY | SEC_RELOC))
+
+On ARM, the .eh_frame input section does not have the SEC_RELOC flag
+set, so this specific change had no effect on ARM.
+
+However, on e.g. m68k and riscv64, the .eh_frame input section does
+have the SEC_RELOC flag set, which means that after commit ba379d08bb78
+("elf2flt: fix for segfault on some ARM ELFs"), read-only relocation
+data sections were placed in .text output section, instead of .data
+output section.
+
+This will result in a fatal error on m68k, xtensa and riscv64:
+ERROR: text=0x3bab8 overlaps data=0x33f60 ?
+
+This is because elf2flt cannot append to .text after .data has been
+appended to.
+
+Note that the binutils maintainer says that the correct thing is
+to put read-only relocation data sections in .text:
+https://sourceware.org/legacy-ml/binutils/2019-10/msg00132.html
+
+So the proper fix is probably to rewrite elf2flt so that it can append
+to .text after .data has been appended to (which will require elf2flt
+to move/relocate everything that has already been appended to .data,
+since the virtual addresses are contiguous).
+
+However, for now, add an exception for m68k, xtensa and riscv64
+(specifically for the problematic input section, .eh_frame), so that we
+get the same behavior as older elf2flt releases, where we put read-only
+relocation data in .data, which was working perfectly fine.
+
+Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
+---
+ elf2flt.c | 11 +++++++++--
+ 1 file changed, 9 insertions(+), 2 deletions(-)
+
+diff --git a/elf2flt.c b/elf2flt.c
+index 9c32f9a..a680c89 100644
+--- a/elf2flt.c
++++ b/elf2flt.c
+@@ -340,8 +340,15 @@ compare_relocs (const void *pa, const void *pb)
+ static bool
+ ro_reloc_data_section_should_be_in_text(asection *s)
+ {
+-  return (s->flags & (SEC_DATA | SEC_READONLY | SEC_RELOC)) ==
+-	  (SEC_DATA | SEC_READONLY | SEC_RELOC);
++  if ((s->flags & (SEC_DATA | SEC_READONLY | SEC_RELOC)) ==
++      (SEC_DATA | SEC_READONLY | SEC_RELOC)) {
++#if defined(TARGET_m68k) || defined(TARGET_riscv64) || defined(TARGET_xtensa)
++    if (!strcmp(".eh_frame", s->name))
++      return false;
++#endif
++    return true;
++  }
++  return false;
+ }
+ 
+ static uint32_t *
+-- 
+2.37.1
+