metag: Remove arch/metag/

The earliest Meta architecture port of Linux I have a record of was an
import of a Meta port of Linux v2.4.1 in February 2004, which was worked
on significantly over the next few years by Graham Whaley, Will Newton,
Matt Fleming, myself and others.

Eventually the port was merged into mainline in v3.9 in March 2013, not
long after Imagination Technologies bought MIPS Technologies and shifted
its CPU focus over to the MIPS architecture.

As a result, though the port was maintained for a while, kept on life
support for a while longer, and useful for testing a few specific
drivers for which I don't have ready access to the equivalent MIPS
hardware, it is now essentially dead with no users.

It is also stuck using an out-of-tree toolchain based on GCC 4.2.4 which
is no longer maintained, now struggles to build modern kernels due to
toolchain bugs, and doesn't itself build with a modern GCC. The latest
buildroot port is still using an old uClibc snapshot which is no longer
served, and the latest uClibc doesn't build with GCC 4.2.4.

So lets call it a day and drop the Meta architecture port from the
kernel. RIP Meta.

Signed-off-by: James Hogan <jhogan@kernel.org>
Link: https://lkml.kernel.org/r/95906b76-6ce1-3f84-eaba-c29b4ae952eb@roeck-us.net
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Graham Whaley <graham.whaley@gmail.com>
Cc: linux-metag@vger.kernel.org

1 files changed, 0 insertions, 247 deletions

diff --git a/arch/metag/mm/fault.c b/arch/metag/mm/fault.c
deleted file mode 100644
index de54fe6..0000000
--- a/arch/metag/mm/fault.c
+++ /dev/null
@@ -1,247 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- *  Meta page fault handling.
- *
- *  Copyright (C) 2005-2012 Imagination Technologies Ltd.
- */
-
-#include <linux/mman.h>
-#include <linux/mm.h>
-#include <linux/kernel.h>
-#include <linux/ptrace.h>
-#include <linux/sched/debug.h>
-#include <linux/interrupt.h>
-#include <linux/uaccess.h>
-
-#include <asm/tlbflush.h>
-#include <asm/mmu.h>
-#include <asm/traps.h>
-
-/* Clear any pending catch buffer state. */
-static void clear_cbuf_entry(struct pt_regs *regs, unsigned long addr,
-			     unsigned int trapno)
-{
-	PTBICTXEXTCB0 cbuf = regs->extcb0;
-
-	switch (trapno) {
-		/* Instruction fetch faults leave no catch buffer state. */
-	case TBIXXF_SIGNUM_IGF:
-	case TBIXXF_SIGNUM_IPF:
-		return;
-	default:
-		if (cbuf[0].CBAddr == addr) {
-			cbuf[0].CBAddr = 0;
-			cbuf[0].CBFlags &= ~TXCATCH0_FAULT_BITS;
-
-			/* And, as this is the ONLY catch entry, we
-			 * need to clear the cbuf bit from the context!
-			 */
-			regs->ctx.SaveMask &= ~(TBICTX_CBUF_BIT |
-						TBICTX_XCBF_BIT);
-
-			return;
-		}
-		pr_err("Failed to clear cbuf entry!\n");
-	}
-}
-
-int show_unhandled_signals = 1;
-
-int do_page_fault(struct pt_regs *regs, unsigned long address,
-		  unsigned int write_access, unsigned int trapno)
-{
-	struct task_struct *tsk;
-	struct mm_struct *mm;
-	struct vm_area_struct *vma, *prev_vma;
-	siginfo_t info;
-	int fault;
-	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
-
-	tsk = current;
-
-	if ((address >= VMALLOC_START) && (address < VMALLOC_END)) {
-		/*
-		 * Synchronize this task's top level page-table
-		 * with the 'reference' page table.
-		 *
-		 * Do _not_ use "tsk" here. We might be inside
-		 * an interrupt in the middle of a task switch..
-		 */
-		int offset = pgd_index(address);
-		pgd_t *pgd, *pgd_k;
-		pud_t *pud, *pud_k;
-		pmd_t *pmd, *pmd_k;
-		pte_t *pte_k;
-
-		pgd = ((pgd_t *)mmu_get_base()) + offset;
-		pgd_k = swapper_pg_dir + offset;
-
-		/* This will never happen with the folded page table. */
-		if (!pgd_present(*pgd)) {
-			if (!pgd_present(*pgd_k))
-				goto bad_area_nosemaphore;
-			set_pgd(pgd, *pgd_k);
-			return 0;
-		}
-
-		pud = pud_offset(pgd, address);
-		pud_k = pud_offset(pgd_k, address);
-		if (!pud_present(*pud_k))
-			goto bad_area_nosemaphore;
-		set_pud(pud, *pud_k);
-
-		pmd = pmd_offset(pud, address);
-		pmd_k = pmd_offset(pud_k, address);
-		if (!pmd_present(*pmd_k))
-			goto bad_area_nosemaphore;
-		set_pmd(pmd, *pmd_k);
-
-		pte_k = pte_offset_kernel(pmd_k, address);
-		if (!pte_present(*pte_k))
-			goto bad_area_nosemaphore;
-
-		/* May only be needed on Chorus2 */
-		flush_tlb_all();
-		return 0;
-	}
-
-	mm = tsk->mm;
-
-	if (faulthandler_disabled() || !mm)
-		goto no_context;
-
-	if (user_mode(regs))
-		flags |= FAULT_FLAG_USER;
-retry:
-	down_read(&mm->mmap_sem);
-
-	vma = find_vma_prev(mm, address, &prev_vma);
-
-	if (!vma || address < vma->vm_start)
-		goto check_expansion;
-
-good_area:
-	if (write_access) {
-		if (!(vma->vm_flags & VM_WRITE))
-			goto bad_area;
-		flags |= FAULT_FLAG_WRITE;
-	} else {
-		if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
-			goto bad_area;
-	}
-
-	/*
-	 * If for any reason at all we couldn't handle the fault,
-	 * make sure we exit gracefully rather than endlessly redo
-	 * the fault.
-	 */
-	fault = handle_mm_fault(vma, address, flags);
-
-	if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))
-		return 0;
-
-	if (unlikely(fault & VM_FAULT_ERROR)) {
-		if (fault & VM_FAULT_OOM)
-			goto out_of_memory;
-		else if (fault & VM_FAULT_SIGSEGV)
-			goto bad_area;
-		else if (fault & VM_FAULT_SIGBUS)
-			goto do_sigbus;
-		BUG();
-	}
-	if (flags & FAULT_FLAG_ALLOW_RETRY) {
-		if (fault & VM_FAULT_MAJOR)
-			tsk->maj_flt++;
-		else
-			tsk->min_flt++;
-		if (fault & VM_FAULT_RETRY) {
-			flags &= ~FAULT_FLAG_ALLOW_RETRY;
-			flags |= FAULT_FLAG_TRIED;
-
-			/*
-			 * No need to up_read(&mm->mmap_sem) as we would
-			 * have already released it in __lock_page_or_retry
-			 * in mm/filemap.c.
-			 */
-
-			goto retry;
-		}
-	}
-
-	up_read(&mm->mmap_sem);
-	return 0;
-
-check_expansion:
-	vma = prev_vma;
-	if (vma && (expand_stack(vma, address) == 0))
-		goto good_area;
-
-bad_area:
-	up_read(&mm->mmap_sem);
-
-bad_area_nosemaphore:
-	if (user_mode(regs)) {
-		info.si_signo = SIGSEGV;
-		info.si_errno = 0;
-		info.si_code = SEGV_MAPERR;
-		info.si_addr = (__force void __user *)address;
-		info.si_trapno = trapno;
-
-		if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&
-		    printk_ratelimit()) {
-			printk("%s%s[%d]: segfault at %lx pc %08x sp %08x write %d trap %#x (%s)",
-			       task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
-			       tsk->comm, task_pid_nr(tsk), address,
-			       regs->ctx.CurrPC, regs->ctx.AX[0].U0,
-			       write_access, trapno, trap_name(trapno));
-			print_vma_addr(" in ", regs->ctx.CurrPC);
-			print_vma_addr(" rtp in ", regs->ctx.DX[4].U1);
-			printk("\n");
-			show_regs(regs);
-		}
-		force_sig_info(SIGSEGV, &info, tsk);
-		return 1;
-	}
-	goto no_context;
-
-do_sigbus:
-	up_read(&mm->mmap_sem);
-
-	/*
-	 * Send a sigbus, regardless of whether we were in kernel
-	 * or user mode.
-	 */
-	info.si_signo = SIGBUS;
-	info.si_errno = 0;
-	info.si_code = BUS_ADRERR;
-	info.si_addr = (__force void __user *)address;
-	info.si_trapno = trapno;
-	force_sig_info(SIGBUS, &info, tsk);
-
-	/* Kernel mode? Handle exceptions or die */
-	if (!user_mode(regs))
-		goto no_context;
-
-	return 1;
-
-	/*
-	 * We ran out of memory, or some other thing happened to us that made
-	 * us unable to handle the page fault gracefully.
-	 */
-out_of_memory:
-	up_read(&mm->mmap_sem);
-	if (user_mode(regs)) {
-		pagefault_out_of_memory();
-		return 1;
-	}
-
-no_context:
-	/* Are we prepared to handle this kernel fault?  */
-	if (fixup_exception(regs)) {
-		clear_cbuf_entry(regs, address, trapno);
-		return 1;
-	}
-
-	die("Oops", regs, (write_access << 15) | trapno, address);
-	do_exit(SIGKILL);
-}