resync master into wip

This is the System V ABI default.

* i386/i386/fpu.c (fpinit): Use FPC_PC_64 instead of FPC_PC_53.
(fp_state_alloc): Likewise.

resync with master

* linux/dev/arch/i386/kernel/irq.c (ndisabled_irq): New array.
(__disable_irq, __enable_irq): New functions, count with ndisabled_irq
before really calling mask_irq/unmask_irq.
(linux_pic_mask): New variable.
(disable_irq, enable_irq): Manage linux_pic_mask and call
__disable_irq/__enable_irq instead of calling mask_irq/unmask_irq.
* linux/src/include/asm-i386/irq.h (__disable_irq, __enable_irq): New
prototypes.

Specs seems to be saying that we should mask an irq out while
acknowledging it with EOI. Also, better acknowledge only the concerned
irq.

* i386/i386at/interrupt.S (interrupt): Mask irq before notifying EOI.
Using specific EOI instead of unspecific EOI.

* i386/i386/pic.h (SPECIFIC_EOI, ROT_NON_SPEC, SET_ROT_AEOI,
ROT_SPEC_EOI, SET_PRIORITY, NO_OPERATION): Shift value left by one bit.

On real hardware, irq 7 seems to get raised often for some reason.

* i386/i386/pic.c (intnull): Only print once the warning about interrupt
being unexpectedly raised.

And simplify prtnull vs intnull vs linux_bad_intr.

* i386/i386/ipl.h (intpri): Remove declaration
* i386/i386/pic.c (prtnull_count): Remove variable.
(prtnull): Remove function.
* i386/i386/pic.h (prtnull): Remove declaration.
* i386/i386at/autoconf.c (take_dev_irq, take_ctlr_irq): Use ivect instead of
intpri to determine irq availability. Do not set intpri.
* i386/i386at/pic_isa.c (ivect): Replace prtnull with intnull.
(intpri): Remove array.
* linux/dev/arch/i386/kernel/irq.c (linux_intr_pri): Remove variable.
(linux_bad_intr): Remove function.
(setup_x86_irq): Do not check intpri coherency. Do not set intpri. Set
default ivect to intnull instead of linux_bad_intr.
(probe_irq_on): Check ivect against intnull instead of linux_bad_intr.
Do not set intpri.
(probe_irq_off): Likewise.
(reserve_mach_irqs): Do not check against prtnull.
(old_clock_pri): Remove variable.
(init_IRQ): Do not set intpri. Do not set ivect to linux_bad_intr.
(restore_IRQ): Do not set ivect.
* i386/i386/pit.c (clkstart): Do not set intpri.
* i386/i386at/kd_mouse.c (kd_mouse_open, kd_mouse_close): Likewise.
* linux/dev/drivers/block/genhd.c (device_setup): Do not set linux_intr_pri.
* linux/dev/glue/block.c (init_partition, device_open): Likewise.
* linux/dev/glue/net.c (device_open): Likewise.
* linux/dev/glue/glue.h (linux_intr_pri, linux_bad_intr): Remove
declarations.

* linux/configfrag.ac (AM53C974, aha1542, eata, eata_pio, ppa, wd7000,
3c515, de600, de620): Disable by default drivers for elder hardware,
which have scary boot messages.
* linux/pcmcia-cs/modules/ds.c (init_pcmcia_ds): Make message about
socket not being found less scary.

* ddb/db_command.c: Include <ipc/mach_port.h>.

* i386/i386at/interrupt.S (interrupt): Call spl7 instead of the
intpri-provided one.

We have removed spl levels, now remove the machinery to manage different
PIC masks according to levels. Only keep machinery to disable interrupts
whatever the level.

* i386/i386/pic.c (pic_mask): Remove array.
(picinit): Do not form PIC mask. Set initial PIC mask to 0.
(form_pic_mask): Remove function.
* i386/i386/pic.h (form_pic_mask, pic_mask): Remove declarations.
* i386/i386/spl.S (SETMASK): Remove macro.
(XEN_SETMASK): Add macro, containing the Xen version of SETMASK.
(spl0, splx_cli, spl) [MACH_XEN]: Call XEN_SETMASK instead of SETMASK.
* i386/i386/pit.c (clkstart): Do not call form_pic_mask.
* i386/i386at/autoconf.c (take_dev_irq, take_ctlr_irq): Likewise.
* i386/i386at/kd_mouse.c (kd_mouse_open, kd_mouse_close): Likewise.
* linux/dev/arch/i386/kernel/irq.c (mask_irq, unmask_irq): Directly update
curr_pic_mask without using pic_mask array.
(init_IRQ, restore_IRQ): do not call form_pic_mask.
* linux/dev/include/asm-i386/system.h: Include <i386/ipl.h>.
(__save_flags, __restore_flags): Use curr_ipl and splx instead of
hardware flags.
* linux/dev/init/main.c (linux_init): Do not call cli.
* linux/dev/kernel/sched.c (linux_timer_intr): Do not use pic_mask.
* linux/src/drivers/block/ide.c (try_to_identify): Disable irq probing.
* linux/src/drivers/scsi/NCR53c406a.c (NCR53c406a_detect): Disable irq
probing.

To avoid even trying to probe IRQs. Nowadays' hardware use the default
IRQ anyway.

* linux/src/drivers/block/ide.c (init_hwif_data): Set hwif->irq to
default_irqs[index].

* i386/i386/spl.S (SETIPL): Remove macro.
(splsoftclock, spl1, spl2, spl3, splnet, splhdw, spl4, splbio, spldcm,
spl5, spltty, splimp, splvm, spl6): Move entries to the spl7 entry.

* i386/intel/pmap.c (pmap_bootstrap, pmap_set_page_readwrite,
pmap_set_page_readonly, pmap_set_page_readonly_init,
pmap_clear_bootstrap_pagetable, pmap_map_mfn, pmap_destroy, pmap_enter,
pmap_collect, phys_attribute_clear): Fix format warnings.

Xen seems to want a whole page for the PAE pdp.

* i386/intel/pmap.c (pmap_init): Make pdpt cache use page-size
allocation.