queue-6.12/openrisc-define-arch-specific-version-of-nop.patch

From dffd1ec9e0224c644fd6b2d1dfbf488497c2b7e4 Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Tue, 20 Jan 2026 12:07:23 -0500
Subject: openrisc: define arch-specific version of nop()

From: Brian Masney <bmasney@redhat.com>

[ Upstream commit 0dfffa5479d6260d04d021f69203b1926f73d889 ]

When compiling a driver written for MIPS on OpenRISC that uses the nop()
function, it fails due to the following error:

    drivers/watchdog/pic32-wdt.c: Assembler messages:
    drivers/watchdog/pic32-wdt.c:125: Error: unrecognized instruction `nop'

The driver currently uses the generic version of nop() from
include/asm-generic/barrier.h:

    #ifndef nop
    #define nop()   asm volatile ("nop")
    #endif

Let's fix this on OpenRISC by defining an architecture-specific version
of nop().

This was tested by performing an allmodconfig openrisc cross compile on
an aarch64 host.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202601180236.BVy480We-lkp@intel.com/
Signed-off-by: Brian Masney <bmasney@redhat.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/openrisc/include/asm/barrier.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/openrisc/include/asm/barrier.h b/arch/openrisc/include/asm/barrier.h
index 7538294721bed..8e592c9909023 100644
--- a/arch/openrisc/include/asm/barrier.h
+++ b/arch/openrisc/include/asm/barrier.h
@@ -4,6 +4,8 @@
 
 #define mb() asm volatile ("l.msync" ::: "memory")
 
+#define nop() asm volatile ("l.nop")
+
 #include <asm-generic/barrier.h>
 
 #endif /* __ASM_BARRIER_H */
-- 
2.51.0