[PATCH 6/8] bfd/binutils: add support for RISC-V CSRs in core files

Andrew Burgess
2020-12-02T17:40:21Z

Adds support for including RISC-V control and status registers into
core files.

bfd/ChangeLog:

* elf-bfd.h (elfcore_write_riscv_csr): Declare.
* elf.c (elfcore_grok_riscv_csr): New function.
(elfcore_grok_note): Handle NT_RISCV_CSR.
(elfcore_write_riscv_csr): New function.
(elfcore_write_register_note): Handle '.reg-riscv-csr'.

binutils/ChangeLog:

* readelf.c (get_note_type): Handle NT_RISCV_CSR.

include/ChangeLog:

* elf/common.h (NT_RISCV_CSR): Define.
---
bfd/ChangeLog | 9 +++++++++
bfd/elf-bfd.h | 2 ++
bfd/elf.c | 31 +++++++++++++++++++++++++++----
binutils/ChangeLog | 5 +++++
binutils/readelf.c | 2 ++
include/ChangeLog | 5 +++++
include/elf/common.h | 2 ++
7 files changed, 52 insertions(+), 4 deletions(-)

diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h
index 5ef69ab5b13..7de09c269f9 100644
--- a/bfd/elf-bfd.h
+++ b/bfd/elf-bfd.h
@@ -2796,6 +2796,8 @@ extern char *elfcore_write_aarch_pauth
(bfd *, char *, int *, const void *, int);
extern char *elfcore_write_arc_v2
(bfd *, char *, int *, const void *, int);
+extern char *elfcore_write_riscv_csr
+ (bfd *, char *, int *, const void *, int);
extern char *elfcore_write_gdb_tdesc
(bfd *, char *, int *, const void *, int);
extern char *elfcore_write_lwpstatus
diff --git a/bfd/elf.c b/bfd/elf.c
index bea5ab12773..62036db4c69 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -9909,6 +9909,12 @@ elfcore_grok_arc_v2 (bfd *abfd, Elf_Internal_Note *note)
return elfcore_make_note_pseudosection (abfd, ".reg-arc-v2", note);
}

+static bfd_boolean
+elfcore_grok_riscv_csr (bfd *abfd, Elf_Internal_Note *note)
+{
+ return elfcore_make_note_pseudosection (abfd, ".reg-riscv-csr", note);
+}
+
static bfd_boolean
elfcore_grok_gdb_tdesc (bfd *abfd, Elf_Internal_Note *note)
{
@@ -10575,6 +10581,9 @@ elfcore_grok_note (bfd *abfd, Elf_Internal_Note *note)
case NT_GDB_TDESC:
return elfcore_grok_gdb_tdesc (abfd, note);

+ case NT_RISCV_CSR:
+ return elfcore_grok_riscv_csr (abfd, note);
+
case NT_PRPSINFO:
case NT_PSINFO:
if (bed->elf_backend_grok_psinfo)
@@ -11956,12 +11965,24 @@ elfcore_write_arc_v2 (bfd *abfd,
note_name, NT_ARC_V2, arc_v2, size);
}

+char *
+elfcore_write_riscv_csr (bfd *abfd,
+ char *buf,
+ int *bufsiz,
+ const void *csrs,
+ int size)
+{
+ const char *note_name = "CORE";
+ return elfcore_write_note (abfd, buf, bufsiz,
+ note_name, NT_RISCV_CSR, csrs, size);
+}
+
char *
elfcore_write_gdb_tdesc (bfd *abfd,
- char *buf,
- int *bufsiz,
- const void *tdesc,
- int size)
+ char *buf,
+ int *bufsiz,
+ const void *tdesc,
+ int size)
{
const char *note_name = "CORE";
return elfcore_write_note (abfd, buf, bufsiz,
@@ -12054,6 +12075,8 @@ elfcore_write_register_note (bfd *abfd,
return elfcore_write_arc_v2 (abfd, buf, bufsiz, data, size);
if (strcmp (section, ".gdb-tdesc") == 0)
return elfcore_write_gdb_tdesc (abfd, buf, bufsiz, data, size);
+ if (strcmp (section, ".reg-riscv-csr") == 0)
+ return elfcore_write_riscv_csr (abfd, buf, bufsiz, data, size);
return NULL;
}

diff --git a/binutils/readelf.c b/binutils/readelf.c
index 5b3871d3e5f..4706d40f7ce 100644
--- a/binutils/readelf.c
+++ b/binutils/readelf.c
@@ -18324,6 +18324,8 @@ get_note_type (Filedata * filedata, unsigned e_type)
return _("NT_ARM_HW_WATCH (AArch hardware watchpoint registers)");
case NT_ARC_V2:
return _("NT_ARC_V2 (ARC HS accumulator/extra registers)");
+ case NT_RISCV_CSR:
+ return _("NT_RISCV_CSR (RISC-V control and status registers)");
case NT_PSTATUS:
return _("NT_PSTATUS (pstatus structure)");
case NT_FPREGS:
diff --git a/include/elf/common.h b/include/elf/common.h
index 1dbf0b11983..54d5d989a39 100644
--- a/include/elf/common.h
+++ b/include/elf/common.h
@@ -663,6 +663,8 @@
/* note name must be "LINUX". */
#define NT_ARC_V2 0x600 /* ARC HS accumulator/extra registers. */
/* note name must be "LINUX". */
+#define NT_RISCV_CSR 0x501 /* RISC-V Control and Status Registers */
+ /* note name must be "CORE". */
#define NT_SIGINFO 0x53494749 /* Fields of siginfo_t. */
#define NT_FILE 0x46494c45 /* Description of mapped files. */

--
2.25.4