Example output of `uname -a` on an initial Gentoo LA64 port, running
the upstream submission version of Linux (with some very minor patches
not influencing output here):

> Linux <hostname> 5.14.0-10342-g37a00851b145 #5 SMP PREEMPT Tue Aug 10 12:56:24 PM CST 2021 loongarch64 GNU/Linux

And the same on the vendor-supplied Loongnix 20 system, with an early
in-house port of Linux, and using the old-world ABI:

> Linux <hostname> 4.19.167-rc5.lnd.1-loongson-3 #1 SMP Sat Apr 17 07:32:32 UTC 2021 loongarch64 loongarch64 loongarch64 GNU/Linux

So a name of "loongarch64" matches both, fortunately.

Signed-off-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 configure   | 7 ++++++-
 meson.build | 2 +-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/configure b/configure
index 1043ccce4f..3a9035385d 100755
--- a/configure
+++ b/configure
@@ -659,6 +659,8 @@ elif check_define __arm__ ; then
   cpu="arm"
 elif check_define __aarch64__ ; then
   cpu="aarch64"
+elif check_define __loongarch64 ; then
+  cpu="loongarch64"
 else
   cpu=$(uname -m)
 fi
@@ -667,7 +669,7 @@ ARCH=
 # Normalise host CPU name and set ARCH.
 # Note that this case should only have supported host CPUs, not guests.
 case "$cpu" in
-  ppc|ppc64|s390x|sparc64|x32|riscv32|riscv64)
+  ppc|ppc64|s390x|sparc64|x32|riscv32|riscv64|loongarch64)
   ;;
   ppc64le)
     ARCH="ppc64"
@@ -4969,6 +4971,9 @@ if test "$linux" = "yes" ; then
   aarch64)
     linux_arch=arm64
     ;;
+  loongarch*)
+    linux_arch=loongarch
+    ;;
   mips64)
     linux_arch=mips
     ;;
diff --git a/meson.build b/meson.build
index 15ef4d3c41..fc55712ac3 100644
--- a/meson.build
+++ b/meson.build
@@ -57,7 +57,7 @@ python = import('python').find_installation()
 
 supported_oses = ['windows', 'freebsd', 'netbsd', 'openbsd', 'darwin', 'sunos', 'linux']
 supported_cpus = ['ppc', 'ppc64', 's390x', 'riscv32', 'riscv64', 'x86', 'x86_64',
-  'arm', 'aarch64', 'mips', 'mips64', 'sparc', 'sparc64']
+  'arm', 'aarch64', 'loongarch64', 'mips', 'mips64', 'sparc', 'sparc64']
 
 cpu = host_machine.cpu_family()
 targetos = host_machine.system()
-- 
2.33.0

On 9/25/21 19:30, WANG Xuerui wrote:
> Example output of `uname -a` on an initial Gentoo LA64 port, running
> the upstream submission version of Linux (with some very minor patches
> not influencing output here):
> 
>> Linux <hostname> 5.14.0-10342-g37a00851b145 #5 SMP PREEMPT Tue Aug 10 12:56:24 PM CST 2021 loongarch64 GNU/Linux
> 
> And the same on the vendor-supplied Loongnix 20 system, with an early
> in-house port of Linux, and using the old-world ABI:
> 
>> Linux <hostname> 4.19.167-rc5.lnd.1-loongson-3 #1 SMP Sat Apr 17 07:32:32 UTC 2021 loongarch64 loongarch64 loongarch64 GNU/Linux

Thanks, helpful.

> 
> So a name of "loongarch64" matches both, fortunately.
> 
> Signed-off-by: WANG Xuerui <git@xen0n.name>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  configure   | 7 ++++++-
>  meson.build | 2 +-
>  2 files changed, 7 insertions(+), 2 deletions(-)