riscv/barrier: Consolidate fence definitions
Disparate fence implementations are consolidated into fence.h.
Also introduce RISCV_FENCE_ASM to make fence macro more reusable.
Signed-off-by: Eric Chan <ericchancf@google.com>
Reviewed-by: Andrea Parri <parri.andrea@gmail.com>
Reviewed-by: Samuel Holland <samuel.holland@sifive.com>
Tested-by: Samuel Holland <samuel.holland@sifive.com>
Link: https://lore.kernel.org/r/20240217131316.3668927-1-ericchancf@google.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
diff --git a/arch/riscv/include/asm/atomic.h b/arch/riscv/include/asm/atomic.h
index 31e6e2e..0e0522e 100644
--- a/arch/riscv/include/asm/atomic.h
+++ b/arch/riscv/include/asm/atomic.h
@@ -17,7 +17,6 @@
#endif
#include <asm/cmpxchg.h>
-#include <asm/barrier.h>
#define __atomic_acquire_fence() \
__asm__ __volatile__(RISCV_ACQUIRE_BARRIER "" ::: "memory")
diff --git a/arch/riscv/include/asm/barrier.h b/arch/riscv/include/asm/barrier.h
index 173b44a..15857db 100644
--- a/arch/riscv/include/asm/barrier.h
+++ b/arch/riscv/include/asm/barrier.h
@@ -11,13 +11,12 @@
#define _ASM_RISCV_BARRIER_H
#ifndef __ASSEMBLY__
+#include <asm/fence.h>
#define nop() __asm__ __volatile__ ("nop")
#define __nops(n) ".rept " #n "\nnop\n.endr\n"
#define nops(n) __asm__ __volatile__ (__nops(n))
-#define RISCV_FENCE(p, s) \
- __asm__ __volatile__ ("fence " #p "," #s : : : "memory")
/* These barriers need to enforce ordering on both devices or memory. */
#define __mb() RISCV_FENCE(iorw, iorw)
diff --git a/arch/riscv/include/asm/cmpxchg.h b/arch/riscv/include/asm/cmpxchg.h
index a608e4d..2fee65c 100644
--- a/arch/riscv/include/asm/cmpxchg.h
+++ b/arch/riscv/include/asm/cmpxchg.h
@@ -8,7 +8,6 @@
#include <linux/bug.h>
-#include <asm/barrier.h>
#include <asm/fence.h>
#define __xchg_relaxed(ptr, new, size) \
diff --git a/arch/riscv/include/asm/fence.h b/arch/riscv/include/asm/fence.h
index 6c26c44..6bcd803 100644
--- a/arch/riscv/include/asm/fence.h
+++ b/arch/riscv/include/asm/fence.h
@@ -1,10 +1,14 @@
#ifndef _ASM_RISCV_FENCE_H
#define _ASM_RISCV_FENCE_H
+#define RISCV_FENCE_ASM(p, s) "\tfence " #p "," #s "\n"
+#define RISCV_FENCE(p, s) \
+ ({ __asm__ __volatile__ (RISCV_FENCE_ASM(p, s) : : : "memory"); })
+
#ifdef CONFIG_SMP
-#define RISCV_ACQUIRE_BARRIER "\tfence r , rw\n"
-#define RISCV_RELEASE_BARRIER "\tfence rw, w\n"
-#define RISCV_FULL_BARRIER "\tfence rw, rw\n"
+#define RISCV_ACQUIRE_BARRIER RISCV_FENCE_ASM(r, rw)
+#define RISCV_RELEASE_BARRIER RISCV_FENCE_ASM(rw, w)
+#define RISCV_FULL_BARRIER RISCV_FENCE_ASM(rw, rw)
#else
#define RISCV_ACQUIRE_BARRIER
#define RISCV_RELEASE_BARRIER
diff --git a/arch/riscv/include/asm/io.h b/arch/riscv/include/asm/io.h
index 42497d4..1c5c641 100644
--- a/arch/riscv/include/asm/io.h
+++ b/arch/riscv/include/asm/io.h
@@ -47,10 +47,10 @@
* sufficient to ensure this works sanely on controllers that support I/O
* writes.
*/
-#define __io_pbr() __asm__ __volatile__ ("fence io,i" : : : "memory");
-#define __io_par(v) __asm__ __volatile__ ("fence i,ior" : : : "memory");
-#define __io_pbw() __asm__ __volatile__ ("fence iow,o" : : : "memory");
-#define __io_paw() __asm__ __volatile__ ("fence o,io" : : : "memory");
+#define __io_pbr() RISCV_FENCE(io, i)
+#define __io_par(v) RISCV_FENCE(i, ior)
+#define __io_pbw() RISCV_FENCE(iow, o)
+#define __io_paw() RISCV_FENCE(o, io)
/*
* Accesses from a single hart to a single I/O address must be ordered. This
diff --git a/arch/riscv/include/asm/mmio.h b/arch/riscv/include/asm/mmio.h
index 4c58ee7..06cadfd 100644
--- a/arch/riscv/include/asm/mmio.h
+++ b/arch/riscv/include/asm/mmio.h
@@ -12,6 +12,7 @@
#define _ASM_RISCV_MMIO_H
#include <linux/types.h>
+#include <asm/fence.h>
#include <asm/mmiowb.h>
/* Generic IO read/write. These perform native-endian accesses. */
@@ -131,8 +132,8 @@
* doesn't define any ordering between the memory space and the I/O space.
*/
#define __io_br() do {} while (0)
-#define __io_ar(v) ({ __asm__ __volatile__ ("fence i,ir" : : : "memory"); })
-#define __io_bw() ({ __asm__ __volatile__ ("fence w,o" : : : "memory"); })
+#define __io_ar(v) RISCV_FENCE(i, ir)
+#define __io_bw() RISCV_FENCE(w, o)
#define __io_aw() mmiowb_set_pending()
#define readb(c) ({ u8 __v; __io_br(); __v = readb_cpu(c); __io_ar(__v); __v; })
diff --git a/arch/riscv/include/asm/mmiowb.h b/arch/riscv/include/asm/mmiowb.h
index 0b2333e7..52ce4a39 100644
--- a/arch/riscv/include/asm/mmiowb.h
+++ b/arch/riscv/include/asm/mmiowb.h
@@ -7,7 +7,7 @@
* "o,w" is sufficient to ensure that all writes to the device have completed
* before the write to the spinlock is allowed to commit.
*/
-#define mmiowb() __asm__ __volatile__ ("fence o,w" : : : "memory");
+#define mmiowb() RISCV_FENCE(o, w)
#include <linux/smp.h>
#include <asm-generic/mmiowb.h>
