Signed-off-by: Chen Pei <cp0613@linux.alibaba.com>

The new THEAD XuanTie C9xx CPU has standard SVPBMT.

Signed-off-by: Chen Pei <cp0613@linux.alibaba.com>

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Just for testing hw, not ready for toolchain.

Fixup headers_install.sh with ptrace.h & VLEN_256

error: ./linux/arch/riscv/include/uapi/asm/ptrace.h: leak CONFIG_VLEN_256 to user-space
./linux/scripts/Makefile.headersinst:63: recipe for target 'usr/include/asm/ptrace.h' failed
make[3]: *** [usr/include/asm/ptrace.h] Error 1
./linux/Makefile:1205: recipe for target 'headers' failed
make[2]: *** [headers] Error 2

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Add compile option for T-HEAD ISA.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

From 5d700a0f ("kexec: avoid compat_alloc_user_space")

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

The RISC-V special option '-mno-relax' which to disable linker relaxations
is supported by GCC8+. For GCC7 and lower versions do not support this
option.

Fixes: fba8a867 ("RISC-V: Add kexec support")
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

raw_smp_processor_id() doesn't return the hart id as stated in
arch/riscv/include/asm/smp.h, use smp_processor_id() instead
to get the cpu id, and cpuid_to_hartid_map() to pass the hart id
to the next kernel. This fixes kexec on HiFive Unleashed/Unmatched
where cpu ids and hart ids don't match (on qemu-virt they match).

Fixes: fba8a867 ("RISC-V: Add kexec support")
Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>

This patch allows Linux to act as a crash kernel for use with
kdump. Userspace will let the crash kernel know about the
memory region it can use through linux,usable-memory property
on the /memory node (overriding its reg property), and about the
memory region where the elf core header of the previous kernel
is saved, through a reserved-memory node with a compatible string
of "linux,elfcorehdr". This approach is the least invasive and
re-uses functionality already present.

I tested this on riscv64 qemu and it works as expected, you
may test it by retrieving the dmesg of the previous kernel
through /proc/vmcore, using the vmcore-dmesg utility from
kexec-tools.

Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>

This patch adds support for kexec on RISC-V. On SMP systems it depends
on HOTPLUG_CPU in order to be able to bring up all harts after kexec.
It also needs a recent OpenSBI version that supports the HSM extension.
I tested it on riscv64 QEMU on both an smp and a non-smp system.

Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

Add RISC-V to the list of supported kexec architectures, we need to
add the definition early-on so that later patches can use it.

EM_RISCV is 243 as per ELF psABI specification here:
https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md



Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

This patch (previously part of my kexec/kdump series) populates
/proc/iomem with the various sections of the kernel image. We need
this for kexec-tools to be able to prepare the crashkernel image
for kdump to work. Since resource tree initialization is not
related to memory initialization I added the code to kernel/setup.c
and removed the original code (derived from the arm64 tree) from
mm/init.c.

Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

Some socs needn't SWIOTLB at all. For code size and mem footprint,
disable it at compile time.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

The sfence.vma may have performance issues, so we use CSR_SMCIR to
replace sfence.vma.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

When CONFIG_SMP=n, it will cause compile error.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Fixup fadvise64_64 arguments error for ltp test with
posix_fadvise03.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Fixup Segmentation fault when rv32 exec rv64 binary.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

[  559.348135] run_ltp.sh[186]: unhandled signal 11 code 0x1 at 0x00000000ff91bca0 in busybox[10000+13d000]
[  559.358679] CPU: 0 PID: 186 Comm: run_ltp.sh Not tainted 5.10.4 #3
[  559.365135] epc: 000000000008d67e ra : 000000000008d674 sp : 0000003fff91bca0
[  559.372457]  gp : 0000000000150548 tp : 00000000001537a0 t0 : 0000000000000000
[  559.379856]  t1 : 2f2f2f2f2f2f2f2f t2 : 000000000000006a s0 : 0000000000154798
[  559.387225]  s1 : 0000000000141eef a0 : 000000000008e4a0 a1 : 00000000001547f0
[  559.394598]  a2 : 0000000000154810 a3 : 000000000000002f a4 : 000000000000002f
[  559.401969]  a5 : 0000000000000000 a6 : 7efefefefefefeff a7 : 00000000000000dd
[  559.409333]  s2 : 0000000000103960 s3 : 0000000000000008 s4 : 0000000000153828
[  559.416696]  s5 : 0000000000000000 s6 : 00000000001547d0 s7 : 0000000000000000
[  559.425234]  s8 : 0000000000000000 s9 : 0000000000157fc0 s10: 00000000001547f0
[  559.432662]  s11: 0000000000000001 t3 : ffffffffffffffff t4 : 0000003ff683e1a8
[  559.440022]  t5 : 0000000000000005 t6 : ffffffffffffffff
[  559.445504] status: 8000000100006620 badaddr: 00000000ff91bca0 cause: 000000000000000d
Segmentation fault

The status shows in UXL_32 mmde, but busybox is 64bit elf.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

 - Fixup sysbench --test=threads performance issue
   Moving sys_call_table into rodata
 - Fixup CONFIG_COMPAT disabled compile error

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

We should use include "../vdso/xxx".

arch/riscv/kernel/compat_vdso/rt_sigreturn.S:3:10: fatal error: ../vdso/rt_sigreturn.S: No such file or directory

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

GDB could debug rv32 vector register.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Public qemu don't support thead custom dma sync instructions.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Add 3 wrapper functions to get vendor id, architecture id and implement id
from M-mode

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

Now, you can use native gdb on riscv64 for rv32 app debugging.

$ uname -a
Linux buildroot 5.16.0-rc4-00036-gbef6b82fdf23-dirty #53 SMP Mon Dec 20 23:06:53 CST 2021 riscv64 GNU/Linux
$ cat /proc/cpuinfo
processor       : 0
hart            : 0
isa             : rv64imafdcsuh
mmu             : sv48

$ file /bin/busybox
/bin/busybox: setuid ELF 32-bit LSB shared object, UCB RISC-V, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-riscv32-ilp32d.so.1, for GNU/Linux 5.15.0, stripped
$ file /usr/bin/gdb
/usr/bin/gdb: ELF 32-bit LSB shared object, UCB RISC-V, version 1 (GNU/Linux), dynamically linked, interpreter /lib/ld-linux-riscv32-ilp32d.so.1, for GNU/Linux 5.15.0, stripped
$ /usr/bin/gdb /bin/busybox
GNU gdb (GDB) 10.2
Copyright (C) 2021 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html

>
...
Reading symbols from /bin/busybox...
(No debugging symbols found in /bin/busybox)
(gdb) b main
Breakpoint 1 at 0x8ddc
(gdb) r
Starting program: /bin/busybox
Failed to read a valid object file image from memory.

Breakpoint 1, 0x555a8ddc in main ()
(gdb) i r
ra             0x77df0b74       0x77df0b74
sp             0x7fdd3d10       0x7fdd3d10
gp             0x5567e800       0x5567e800 <bb_common_bufsiz1+160>
tp             0x77f64280       0x77f64280
t0             0x0      0
t1             0x555a6fac       1431990188
t2             0x77dd8db4       2011008436
fp             0x7fdd3e34       0x7fdd3e34
s1             0x7fdd3e34       2145205812
a0             0xffffffff       -1
a1             0x2000   8192
a2             0x7fdd3e3c       2145205820
a3             0x0      0
a4             0x7fdd3d30       2145205552
a5             0x555a8dc0       1431997888
a6             0x77f2c170       2012397936
a7             0x6a7c7a2f       1786542639
s2             0x0      0
s3             0x0      0
s4             0x555a8dc0       1431997888
s5             0x77f8a3a8       2012783528
s6             0x7fdd3e3c       2145205820
s7             0x5567cecc       1432866508
--Type <RET> for more, q to quit, c to continue without paging--
s8             0x1      1
s9             0x0      0
s10            0x55634448       1432568904
s11            0x0      0
t3             0x77df0bb8       2011106232
t4             0x42fc   17148
t5             0x0      0
t6             0x40     64
pc             0x555a8ddc       0x555a8ddc <main+28>
(gdb) si
0x555a78f0 in mallopt@plt ()
(gdb) c
Continuing.
BusyBox v1.34.1 (2021-12-19 22:39:48 CST) multi-call binary.
BusyBox is copyrighted by many authors between 1998-2015.
Licensed under GPLv2. See source distribution for detailed
copyright notices.

Usage: busybox [function [arguments]...]
   or: busybox --list[-full]
...
[Inferior 1 (process 107) exited normally]
(gdb) q

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Implement compat_setup_rt_frame for sigcontext save & restore. The
main process is the same with signal, but the rv32 pt_regs' size
is different from rv64's, so we needs convert them.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Reconstruct __setup_additional_pages() by appending vdso info
pointer argument to meet compat_vdso_info requirement. And change
vm_special_mapping *dm, *cm initialization into static.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

There is no vgettimeofday supported in rv32 that makes simple to
generate rv32 vdso code which only needs riscv64 compiler. Other
architectures need change compiler or -m (machine parameter) to
support vdso32 compiling. If rv32 support vgettimeofday (which
cause C compile) in future, we would add CROSS_COMPILE to support
that makes more requirement on compiler enviornment.

linux-rv64/arch/riscv/kernel/compat_vdso/compat_vdso.so.dbg:
file format elf64-littleriscv

Disassembly of section .text:

0000000000000800 <__vdso_rt_sigreturn>:
 800:   08b00893                li      a7,139
 804:   00000073                ecall
 808:   0000                    unimp
        ...

000000000000080c <__vdso_getcpu>:
 80c:   0a800893                li      a7,168
 810:   00000073                ecall
 814:   8082                    ret
        ...

0000000000000818 <__vdso_flush_icache>:
 818:   10300893                li      a7,259
 81c:   00000073                ecall
 820:   8082                    ret

linux-rv32/arch/riscv/kernel/vdso/vdso.so.dbg:
file format elf32-littleriscv

Disassembly of section .text:

00000800 <__vdso_rt_sigreturn>:
 800:   08b00893                li      a7,139
 804:   00000073                ecall
 808:   0000                    unimp
        ...

0000080c <__vdso_getcpu>:
 80c:   0a800893                li      a7,168
 810:   00000073                ecall
 814:   8082                    ret
        ...

00000818 <__vdso_flush_icache>:
 818:   10300893                li      a7,259
 81c:   00000073                ecall
 820:   8082                    ret

Finally, reuse all *.S from vdso in compat_vdso that makes
implementation clear and readable.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Adds initial skeletal COMPAT Kbuild (Runing 32bit U-mode on 64bit
S-mode) support.
 - Setup kconfig & dummy functions for compiling.
 - Implement compat_start_thread by the way.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Implement necessary type and macro for compat elf. See the code
comment for detail.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Implement the entry of compat_sys_call_table[] in asm. Ref to
riscv-privileged spec 4.1.1 Supervisor Status Register (sstatus):

 BIT[32:33] = UXL[1:0]:
 - 1:32
 - 2:64
 - 3:128

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Implement compat_syscall_table.c with compat_sys_call_table & fixup
system call such as truncate64,pread64,fallocate which need two
regs to indicate 64bit-arg (copied from arm64).

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Make TASK_SIZE from const to dynamic detect TIF_32BIT flag
function. Refer to arm64 to implement DEFAULT_MAP_WINDOW_64 for
efi-stub.

Limit 32-bit compatible process in 0-2GB virtual address range
(which is enough for real scenarios), because it could avoid
address sign extend problem when 32-bit enter 64-bit and ease
software design.

The standard 32-bit TASK_SIZE is 0x9dc00000:FIXADDR_START, and
compared to a compatible 32-bit, it increases 476MB for the
application's virtual address.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Implement asm/compat.h for struct compat_xxx, RLIM_INFINITY,
OFF_T_MAX, is_compat_task, compat_user_regset, regset convert.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>

Make "uapi asm unistd.h" could be used for architectures' COMPAT
mode. The __SYSCALL_COMPAT is first used in riscv.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>