MN10300: Fix ret_from_kernel_thread

ret_from_kernel_thread needs to set A2 to the thread_info pointer before
jumping to syscall_exit.

Without this, we never correctly start userspace.

This was caused by the rejuggling of the fork/exec paths in commit
ddf23e87a804 ("mn10300: switch to saner kernel_execve() semantics")

Reported-by: Ken Cox <jkc@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ken Cox <jkc@redhat.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
MN10300: Enable IRQs more in system call exit work path

Enable IRQs when calling schedule() for TIF_NEED_RESCHED and
do_notify_resume().  If interrupts are enabled during do_notify_resume(), a
warning can be seen (see lower down).

Whilst we're at it, resume_userspace can be made local to entry.S as it is not
called outside of there and it can be merged with the part of work_resched that
occurs after schedule() is called.

  WARNING: at kernel/softirq.c:160 local_bh_enable+0x42/0xa0()
  Call Trace:
    local_bh_enable+0x42/0xa0
    unix_release_sock+0x86/0x23c
    unix_release+0x20/0x28
    sock_release+0x17/0x88
    sock_close+0x20/0x28
    __fput+0xc9/0x1fc
    ____fput+0xb/0x10
    task_work_run+0x64/0x78
    do_notify_resume+0x53d/0x544
    work_notifysig+0xa/0xc

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ken Cox <jkc@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
MN10300: ASB2305's PCI code needs the definition of XIRQ1

The code for PCI in the ASB2305 needs the definition of XIRQ1 from proc/irq.h
otherwise the following error appears:

  arch/mn10300/unit-asb2305/pci.c: In function 'unit_pci_init':
  arch/mn10300/unit-asb2305/pci.c:481: error: 'XIRQ1' undeclared (first use in this function)
  arch/mn10300/unit-asb2305/pci.c:481: error: (Each undeclared identifier is reported only once
  arch/mn10300/unit-asb2305/pci.c:481: error: for each function it appears in.)

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ken Cox <jkc@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
MN10300: Need pci_iomap() and __pci_ioport_map() defining

Include the generic definitions of pci_iomap() and __pci_ioport_map()
otherwise we can get errors like:

  lib/pci_iomap.c: In function 'pci_iomap':
  lib/pci_iomap.c:37: error: implicit declaration of function '__pci_ioport_map'
  lib/pci_iomap.c:37: warning: return makes pointer from integer without a cast

and:

  drivers/pci/quirks.c: In function 'disable_igfx_irq':
  drivers/pci/quirks.c:2893: error: implicit declaration of function 'pci_iomap'
  drivers/pci/quirks.c:2893: warning: initialization makes pointer from integer without a cast
  drivers/pci/quirks.c: In function 'reset_ivb_igd':
  drivers/pci/quirks.c:3133: warning: assignment makes pointer from integer without a cast

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ken Cox <jkc@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'mn10300' (mn10300 fixes from David Howells)

Merge mn10300 fixes from David Howells.

* emailed patches from David Howells <dhowells@redhat.com>:
  MN10300: Need pci_iomap() and __pci_ioport_map() defining
  MN10300: ASB2305's PCI code needs the definition of XIRQ1
  MN10300: Enable IRQs more in system call exit work path
  MN10300: Fix ret_from_kernel_thread