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, 269 deletions

diff --git a/arch/tile/kernel/smpboot.c b/arch/tile/kernel/smpboot.c
deleted file mode 100644
index 869c22e57561..000000000000
--- a/arch/tile/kernel/smpboot.c
+++ /dev/null
@@ -1,269 +0,0 @@
-/*
- * Copyright 2010 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.
- */
-
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/sched/mm.h>
-#include <linux/sched/task.h>
-#include <linux/kernel_stat.h>
-#include <linux/bootmem.h>
-#include <linux/notifier.h>
-#include <linux/cpu.h>
-#include <linux/percpu.h>
-#include <linux/delay.h>
-#include <linux/err.h>
-#include <linux/irq.h>
-#include <asm/mmu_context.h>
-#include <asm/tlbflush.h>
-#include <asm/sections.h>
-
-/* State of each CPU. */
-static DEFINE_PER_CPU(int, cpu_state) = { 0 };
-
-/* The messaging code jumps to this pointer during boot-up */
-unsigned long start_cpu_function_addr;
-
-/* Called very early during startup to mark boot cpu as online */
-void __init smp_prepare_boot_cpu(void)
-{
-	int cpu = smp_processor_id();
-	set_cpu_online(cpu, 1);
-	set_cpu_present(cpu, 1);
-	__this_cpu_write(cpu_state, CPU_ONLINE);
-
-	init_messaging();
-}
-
-static void start_secondary(void);
-
-/*
- * Called at the top of init() to launch all the other CPUs.
- * They run free to complete their initialization and then wait
- * until they get an IPI from the boot cpu to come online.
- */
-void __init smp_prepare_cpus(unsigned int max_cpus)
-{
-	long rc;
-	int cpu, cpu_count;
-	int boot_cpu = smp_processor_id();
-
-	current_thread_info()->cpu = boot_cpu;
-
-	/*
-	 * Pin this task to the boot CPU while we bring up the others,
-	 * just to make sure we don't uselessly migrate as they come up.
-	 */
-	rc = sched_setaffinity(current->pid, cpumask_of(boot_cpu));
-	if (rc != 0)
-		pr_err("Couldn't set init affinity to boot cpu (%ld)\n", rc);
-
-	/* Print information about disabled and dataplane cpus. */
-	print_disabled_cpus();
-
-	/*
-	 * Tell the messaging subsystem how to respond to the
-	 * startup message.  We use a level of indirection to avoid
-	 * confusing the linker with the fact that the messaging
-	 * subsystem is calling __init code.
-	 */
-	start_cpu_function_addr = (unsigned long) &online_secondary;
-
-	/* Set up thread context for all new processors. */
-	cpu_count = 1;
-	for (cpu = 0; cpu < NR_CPUS; ++cpu)	{
-		struct task_struct *idle;
-
-		if (cpu == boot_cpu)
-			continue;
-
-		if (!cpu_possible(cpu)) {
-			/*
-			 * Make this processor do nothing on boot.
-			 * Note that we don't give the boot_pc function
-			 * a stack, so it has to be assembly code.
-			 */
-			per_cpu(boot_sp, cpu) = 0;
-			per_cpu(boot_pc, cpu) = (unsigned long) smp_nap;
-			continue;
-		}
-
-		/* Create a new idle thread to run start_secondary() */
-		idle = fork_idle(cpu);
-		if (IS_ERR(idle))
-			panic("failed fork for CPU %d", cpu);
-		idle->thread.pc = (unsigned long) start_secondary;
-
-		/* Make this thread the boot thread for this processor */
-		per_cpu(boot_sp, cpu) = task_ksp0(idle);
-		per_cpu(boot_pc, cpu) = idle->thread.pc;
-
-		++cpu_count;
-	}
-	BUG_ON(cpu_count > (max_cpus ? max_cpus : 1));
-
-	/* Fire up the other tiles, if any */
-	init_cpu_present(cpu_possible_mask);
-	if (cpumask_weight(cpu_present_mask) > 1) {
-		mb();  /* make sure all data is visible to new processors */
-		hv_start_all_tiles();
-	}
-}
-
-static __initdata struct cpumask init_affinity;
-
-static __init int reset_init_affinity(void)
-{
-	long rc = sched_setaffinity(current->pid, &init_affinity);
-	if (rc != 0)
-		pr_warn("couldn't reset init affinity (%ld)\n", rc);
-	return 0;
-}
-late_initcall(reset_init_affinity);
-
-static struct cpumask cpu_started;
-
-/*
- * Activate a secondary processor.  Very minimal; don't add anything
- * to this path without knowing what you're doing, since SMP booting
- * is pretty fragile.
- */
-static void start_secondary(void)
-{
-	int cpuid;
-
-	preempt_disable();
-
-	cpuid = smp_processor_id();
-
-	/* Set our thread pointer appropriately. */
-	set_my_cpu_offset(__per_cpu_offset[cpuid]);
-
-	/*
-	 * In large machines even this will slow us down, since we
-	 * will be contending for for the printk spinlock.
-	 */
-	/* printk(KERN_DEBUG "Initializing CPU#%d\n", cpuid); */
-
-	/* Initialize the current asid for our first page table. */
-	__this_cpu_write(current_asid, min_asid);
-
-	/* Set up this thread as another owner of the init_mm */
-	mmgrab(&init_mm);
-	current->active_mm = &init_mm;
-	if (current->mm)
-		BUG();
-	enter_lazy_tlb(&init_mm, current);
-
-	/* Allow hypervisor messages to be received */
-	init_messaging();
-	local_irq_enable();
-
-	/* Indicate that we're ready to come up. */
-	/* Must not do this before we're ready to receive messages */
-	if (cpumask_test_and_set_cpu(cpuid, &cpu_started)) {
-		pr_warn("CPU#%d already started!\n", cpuid);
-		for (;;)
-			local_irq_enable();
-	}
-
-	smp_nap();
-}
-
-/*
- * Bring a secondary processor online.
- */
-void online_secondary(void)
-{
-	/*
-	 * low-memory mappings have been cleared, flush them from
-	 * the local TLBs too.
-	 */
-	local_flush_tlb();
-
-	BUG_ON(in_interrupt());
-
-	/* This must be done before setting cpu_online_mask */
-	wmb();
-
-	notify_cpu_starting(smp_processor_id());
-
-	set_cpu_online(smp_processor_id(), 1);
-	__this_cpu_write(cpu_state, CPU_ONLINE);
-
-	/* Set up tile-specific state for this cpu. */
-	setup_cpu(0);
-
-	/* Set up tile-timer clock-event device on this cpu */
-	setup_tile_timer();
-
-	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
-}
-
-int __cpu_up(unsigned int cpu, struct task_struct *tidle)
-{
-	/* Wait 5s total for all CPUs for them to come online */
-	static int timeout;
-	for (; !cpumask_test_cpu(cpu, &cpu_started); timeout++) {
-		if (timeout >= 50000) {
-			pr_info("skipping unresponsive cpu%d\n", cpu);
-			local_irq_enable();
-			return -EIO;
-		}
-		udelay(100);
-	}
-
-	local_irq_enable();
-	per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
-
-	/* Unleash the CPU! */
-	send_IPI_single(cpu, MSG_TAG_START_CPU);
-	while (!cpumask_test_cpu(cpu, cpu_online_mask))
-		cpu_relax();
-	return 0;
-}
-
-static void panic_start_cpu(void)
-{
-	panic("Received a MSG_START_CPU IPI after boot finished.");
-}
-
-void __init smp_cpus_done(unsigned int max_cpus)
-{
-	int cpu, next, rc;
-
-	/* Reset the response to a (now illegal) MSG_START_CPU IPI. */
-	start_cpu_function_addr = (unsigned long) &panic_start_cpu;
-
-	cpumask_copy(&init_affinity, cpu_online_mask);
-
-	/*
-	 * Pin ourselves to a single cpu in the initial affinity set
-	 * so that kernel mappings for the rootfs are not in the dataplane,
-	 * if set, and to avoid unnecessary migrating during bringup.
-	 * Use the last cpu just in case the whole chip has been
-	 * isolated from the scheduler, to keep init away from likely
-	 * more useful user code.  This also ensures that work scheduled
-	 * via schedule_delayed_work() in the init routines will land
-	 * on this cpu.
-	 */
-	for (cpu = cpumask_first(&init_affinity);
-	     (next = cpumask_next(cpu, &init_affinity)) < nr_cpu_ids;
-	     cpu = next)
-		;
-	rc = sched_setaffinity(current->pid, cpumask_of(cpu));
-	if (rc != 0)
-		pr_err("Couldn't set init affinity to cpu %d (%d)\n", cpu, rc);
-}