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, 239 deletions

diff --git a/arch/tile/kernel/ftrace.c b/arch/tile/kernel/ftrace.c
deleted file mode 100644
index b827a418b155..000000000000
--- a/arch/tile/kernel/ftrace.c
+++ /dev/null
@@ -1,239 +0,0 @@
-/*
- * Copyright 2012 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.
- *
- * TILE-Gx specific ftrace support
- */
-
-#include <linux/ftrace.h>
-#include <linux/uaccess.h>
-
-#include <asm/cacheflush.h>
-#include <asm/ftrace.h>
-#include <asm/sections.h>
-#include <asm/insn.h>
-
-#include <arch/opcode.h>
-
-#ifdef CONFIG_DYNAMIC_FTRACE
-
-static int machine_stopped __read_mostly;
-
-int ftrace_arch_code_modify_prepare(void)
-{
-	machine_stopped = 1;
-	return 0;
-}
-
-int ftrace_arch_code_modify_post_process(void)
-{
-	flush_icache_range(0, CHIP_L1I_CACHE_SIZE());
-	machine_stopped = 0;
-	return 0;
-}
-
-/*
- * Put { move r10, lr; jal ftrace_caller } in a bundle, this lets dynamic
- * tracer just add one cycle overhead to every kernel function when disabled.
- */
-static unsigned long ftrace_gen_branch(unsigned long pc, unsigned long addr,
-				       bool link)
-{
-	tilegx_bundle_bits opcode_x0, opcode_x1;
-	long pcrel_by_instr = (addr - pc) >> TILEGX_LOG2_BUNDLE_SIZE_IN_BYTES;
-
-	if (link) {
-		/* opcode: jal addr */
-		opcode_x1 =
-			create_Opcode_X1(JUMP_OPCODE_X1) |
-			create_JumpOpcodeExtension_X1(JAL_JUMP_OPCODE_X1) |
-			create_JumpOff_X1(pcrel_by_instr);
-	} else {
-		/* opcode: j addr */
-		opcode_x1 =
-			create_Opcode_X1(JUMP_OPCODE_X1) |
-			create_JumpOpcodeExtension_X1(J_JUMP_OPCODE_X1) |
-			create_JumpOff_X1(pcrel_by_instr);
-	}
-
-	/*
-	 * Also put { move r10, lr; jal ftrace_stub } in a bundle, which
-	 * is used to replace the instruction in address ftrace_call.
-	 */
-	if (addr == FTRACE_ADDR || addr == (unsigned long)ftrace_stub) {
-		/* opcode: or r10, lr, zero */
-		opcode_x0 =
-			create_Dest_X0(10) |
-			create_SrcA_X0(TREG_LR) |
-			create_SrcB_X0(TREG_ZERO) |
-			create_RRROpcodeExtension_X0(OR_RRR_0_OPCODE_X0) |
-			create_Opcode_X0(RRR_0_OPCODE_X0);
-	} else {
-		/* opcode: fnop */
-		opcode_x0 =
-			create_UnaryOpcodeExtension_X0(FNOP_UNARY_OPCODE_X0) |
-			create_RRROpcodeExtension_X0(UNARY_RRR_0_OPCODE_X0) |
-			create_Opcode_X0(RRR_0_OPCODE_X0);
-	}
-
-	return opcode_x1 | opcode_x0;
-}
-
-static unsigned long ftrace_nop_replace(struct dyn_ftrace *rec)
-{
-	return NOP();
-}
-
-static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr)
-{
-	return ftrace_gen_branch(pc, addr, true);
-}
-
-static int ftrace_modify_code(unsigned long pc, unsigned long old,
-			      unsigned long new)
-{
-	unsigned long pc_wr;
-
-	/* Check if the address is in kernel text space and module space. */
-	if (!kernel_text_address(pc))
-		return -EINVAL;
-
-	/* Operate on writable kernel text mapping. */
-	pc_wr = ktext_writable_addr(pc);
-
-	if (probe_kernel_write((void *)pc_wr, &new, MCOUNT_INSN_SIZE))
-		return -EPERM;
-
-	smp_wmb();
-
-	if (!machine_stopped && num_online_cpus() > 1)
-		flush_icache_range(pc, pc + MCOUNT_INSN_SIZE);
-
-	return 0;
-}
-
-int ftrace_update_ftrace_func(ftrace_func_t func)
-{
-	unsigned long pc, old;
-	unsigned long new;
-	int ret;
-
-	pc = (unsigned long)&ftrace_call;
-	memcpy(&old, &ftrace_call, MCOUNT_INSN_SIZE);
-	new = ftrace_call_replace(pc, (unsigned long)func);
-
-	ret = ftrace_modify_code(pc, old, new);
-
-	return ret;
-}
-
-int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
-{
-	unsigned long new, old;
-	unsigned long ip = rec->ip;
-
-	old = ftrace_nop_replace(rec);
-	new = ftrace_call_replace(ip, addr);
-
-	return ftrace_modify_code(rec->ip, old, new);
-}
-
-int ftrace_make_nop(struct module *mod,
-		    struct dyn_ftrace *rec, unsigned long addr)
-{
-	unsigned long ip = rec->ip;
-	unsigned long old;
-	unsigned long new;
-	int ret;
-
-	old = ftrace_call_replace(ip, addr);
-	new = ftrace_nop_replace(rec);
-	ret = ftrace_modify_code(ip, old, new);
-
-	return ret;
-}
-
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
-#endif /* CONFIG_DYNAMIC_FTRACE */
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
-			   unsigned long frame_pointer)
-{
-	unsigned long return_hooker = (unsigned long) &return_to_handler;
-	struct ftrace_graph_ent trace;
-	unsigned long old;
-	int err;
-
-	if (unlikely(atomic_read(&current->tracing_graph_pause)))
-		return;
-
-	old = *parent;
-	*parent = return_hooker;
-
-	err = ftrace_push_return_trace(old, self_addr, &trace.depth,
-				       frame_pointer, NULL);
-	if (err == -EBUSY) {
-		*parent = old;
-		return;
-	}
-
-	trace.func = self_addr;
-
-	/* Only trace if the calling function expects to */
-	if (!ftrace_graph_entry(&trace)) {
-		current->curr_ret_stack--;
-		*parent = old;
-	}
-}
-
-#ifdef CONFIG_DYNAMIC_FTRACE
-extern unsigned long ftrace_graph_call;
-
-static int __ftrace_modify_caller(unsigned long *callsite,
-				  void (*func) (void), bool enable)
-{
-	unsigned long caller_fn = (unsigned long) func;
-	unsigned long pc = (unsigned long) callsite;
-	unsigned long branch = ftrace_gen_branch(pc, caller_fn, false);
-	unsigned long nop = NOP();
-	unsigned long old = enable ? nop : branch;
-	unsigned long new = enable ? branch : nop;
-
-	return ftrace_modify_code(pc, old, new);
-}
-
-static int ftrace_modify_graph_caller(bool enable)
-{
-	int ret;
-
-	ret = __ftrace_modify_caller(&ftrace_graph_call,
-				     ftrace_graph_caller,
-				     enable);
-
-	return ret;
-}
-
-int ftrace_enable_ftrace_graph_caller(void)
-{
-	return ftrace_modify_graph_caller(true);
-}
-
-int ftrace_disable_ftrace_graph_caller(void)
-{
-	return ftrace_modify_graph_caller(false);
-}
-#endif /* CONFIG_DYNAMIC_FTRACE */
-#endif /* CONFIG_FUNCTION_GRAPH_TRACER */