arch: remove tile port

The Tile architecture port was added by Chris Metcalf in 2010, and
maintained until early 2018 when he orphaned it due to his departure
from Mellanox, and nobody else stepped up to maintain it. The product
line is still around in the form of the BlueField SoC, but no longer
uses the Tile architecture.

There are also still products for sale with Tile-GX SoCs, notably the
Mikrotik CCR router family. The products all use old (linux-3.3) kernels
with lots of patches and won't be upgraded by their manufacturers. There
have been efforts to port both OpenWRT and Debian to these, but both
projects have stalled and are very unlikely to be continued in the future.

Given that we are reasonably sure that nobody is still using the port
with an upstream kernel any more, it seems better to remove it now while
the port is in a good shape than to let it bitrot for a few years first.

Cc: Chris Metcalf <chris.d.metcalf@gmail.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: http://www.mellanox.com/page/npu_multicore_overview
Link: https://jenkins.debian.net/view/rebootstrap/job/rebootstrap_tilegx_gcc7/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 0 insertions, 138 deletions

diff --git a/arch/tile/include/asm/spinlock_64.h b/arch/tile/include/asm/spinlock_64.h
deleted file mode 100644
index 5b616ef642a8..000000000000
--- a/arch/tile/include/asm/spinlock_64.h
+++ /dev/null
@@ -1,138 +0,0 @@
-/*
- * Copyright 2011 Tilera Corporation. All Rights Reserved.
- *
- *   This program is free software; you can redistribute it and/or
- *   modify it under the terms of the GNU General Public License
- *   as published by the Free Software Foundation, version 2.
- *
- *   This program is distributed in the hope that it will be useful, but
- *   WITHOUT ANY WARRANTY; without even the implied warranty of
- *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
- *   NON INFRINGEMENT.  See the GNU General Public License for
- *   more details.
- *
- * 64-bit SMP ticket spinlocks, allowing only a single CPU anywhere
- * (the type definitions are in asm/spinlock_types.h)
- */
-
-#ifndef _ASM_TILE_SPINLOCK_64_H
-#define _ASM_TILE_SPINLOCK_64_H
-
-#include <linux/compiler.h>
-
-/* Shifts and masks for the various fields in "lock". */
-#define __ARCH_SPIN_CURRENT_SHIFT	17
-#define __ARCH_SPIN_NEXT_MASK		0x7fff
-#define __ARCH_SPIN_NEXT_OVERFLOW	0x8000
-
-/*
- * Return the "current" portion of a ticket lock value,
- * i.e. the number that currently owns the lock.
- */
-static inline u32 arch_spin_current(u32 val)
-{
-	return val >> __ARCH_SPIN_CURRENT_SHIFT;
-}
-
-/*
- * Return the "next" portion of a ticket lock value,
- * i.e. the number that the next task to try to acquire the lock will get.
- */
-static inline u32 arch_spin_next(u32 val)
-{
-	return val & __ARCH_SPIN_NEXT_MASK;
-}
-
-/* The lock is locked if a task would have to wait to get it. */
-static inline int arch_spin_is_locked(arch_spinlock_t *lock)
-{
-	/* Use READ_ONCE() to ensure that calling this in a loop is OK. */
-	u32 val = READ_ONCE(lock->lock);
-	return arch_spin_current(val) != arch_spin_next(val);
-}
-
-/* Bump the current ticket so the next task owns the lock. */
-static inline void arch_spin_unlock(arch_spinlock_t *lock)
-{
-	wmb();  /* guarantee anything modified under the lock is visible */
-	__insn_fetchadd4(&lock->lock, 1U << __ARCH_SPIN_CURRENT_SHIFT);
-}
-
-void arch_spin_lock_slow(arch_spinlock_t *lock, u32 val);
-
-/* Grab the "next" ticket number and bump it atomically.
- * If the current ticket is not ours, go to the slow path.
- * We also take the slow path if the "next" value overflows.
- */
-static inline void arch_spin_lock(arch_spinlock_t *lock)
-{
-	u32 val = __insn_fetchadd4(&lock->lock, 1);
-	u32 ticket = val & (__ARCH_SPIN_NEXT_MASK | __ARCH_SPIN_NEXT_OVERFLOW);
-	if (unlikely(arch_spin_current(val) != ticket))
-		arch_spin_lock_slow(lock, ticket);
-}
-
-/* Try to get the lock, and return whether we succeeded. */
-int arch_spin_trylock(arch_spinlock_t *lock);
-
-/*
- * Read-write spinlocks, allowing multiple readers
- * but only one writer.
- *
- * We use fetchadd() for readers, and fetchor() with the sign bit
- * for writers.
- */
-
-#define __WRITE_LOCK_BIT (1 << 31)
-
-static inline int arch_write_val_locked(int val)
-{
-	return val < 0;  /* Optimize "val & __WRITE_LOCK_BIT". */
-}
-
-extern void __read_lock_failed(arch_rwlock_t *rw);
-
-static inline void arch_read_lock(arch_rwlock_t *rw)
-{
-	u32 val = __insn_fetchaddgez4(&rw->lock, 1);
-	if (unlikely(arch_write_val_locked(val)))
-		__read_lock_failed(rw);
-}
-
-extern void __write_lock_failed(arch_rwlock_t *rw, u32 val);
-
-static inline void arch_write_lock(arch_rwlock_t *rw)
-{
-	u32 val = __insn_fetchor4(&rw->lock, __WRITE_LOCK_BIT);
-	if (unlikely(val != 0))
-		__write_lock_failed(rw, val);
-}
-
-static inline void arch_read_unlock(arch_rwlock_t *rw)
-{
-	__insn_mf();
-	__insn_fetchadd4(&rw->lock, -1);
-}
-
-static inline void arch_write_unlock(arch_rwlock_t *rw)
-{
-	__insn_mf();
-	__insn_exch4(&rw->lock, 0);  /* Avoid waiting in the write buffer. */
-}
-
-static inline int arch_read_trylock(arch_rwlock_t *rw)
-{
-	return !arch_write_val_locked(__insn_fetchaddgez4(&rw->lock, 1));
-}
-
-static inline int arch_write_trylock(arch_rwlock_t *rw)
-{
-	u32 val = __insn_fetchor4(&rw->lock, __WRITE_LOCK_BIT);
-	if (likely(val == 0))
-		return 1;
-	if (!arch_write_val_locked(val))
-		__insn_fetchand4(&rw->lock, ~__WRITE_LOCK_BIT);
-	return 0;
-}
-
-#endif /* _ASM_TILE_SPINLOCK_64_H */