Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
This fixes support for rev c8 of the ALi/ULi PATA, and keeps pcmcia in
sync so ide_cs and pata_pcmcia are interchangable, both are only changes
to constants.
Right now rev 0xC8 and higher don't work with libata but 0xc8 is in the
field now.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev:
[libata] pata_artop: kill gcc warning
[PATCH] libata: turn off NCQ if queue depth is adjusted to 1
[PATCH] libata: cosmetic changes to constants
[libata] DocBook minor updates, fixes
[libata] PCI ID table cleanup in various drivers
[libata] Print out Status register, if a BSY-sleep takes too long
[libata] init probe_ent->private_data in a common location
[libata] minor PCI IDE probe fixes and cleanups
[libata] Use new PCI_VDEVICE() macro to dramatically shorten ID lists
[PATCH] Fix reference of uninitialised memory in ata_device_add()
gcc complains thusly:
drivers/ata/pata_artop.c: In function ‘artop_init_one’:
drivers/ata/pata_artop.c:429: warning: ‘info’ may be used uninitialized in this function
While this warning is indeed bogus, even with improved static analysis
and value range propagation, gcc will probably never be able to detect
this.
Add a BUG_ON() to trap invalid driver_data entries in the PCI table.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* Use PCI_VDEVICE() macro
* const-ify pci_device_id table
* standardize list terminator as "{ }"
* convert spaces to tab in pci_driver struct (Alan-ism)
* various minor whitespace cleanups
Signed-off-by: Jeff Garzik <jeff@garzik.org>
We have the info stored in an ata_busy_sleep() variable, so might as
well print it, and provide some additional diagnostic info.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Don't write the same code twice, in two different functions, when they
both call the same initialization function, with the same private_data
pointer info.
Also, note a bug found with a FIXME.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* Replace needless 'n_ports > 2' check with a simple BUG_ON().
No existing driver ever wants more than 2 ports.
* Delete ATA_FLAG_NO_LEGACY check. No current driver uses
ata_pci_init_one(), that sets this flag.
* Move PCI_CLASS_PROG register read below pci_enable_device()
* Handle ata_device_add() failure
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ata_device_add fails, calls ata_host_remove with pointers to unitialized
memory.
Signed-off-by: Dave Jones <davej@redhat.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The PATA driver set got converted to the new error handling setup, but
the old hooks were accidentally left in place. Now, removed.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Only two of three ata_port_operations structs had a ->data_xfer member,
which led to, uh, a lack of data xfer.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This removes the layering violation where drivers have to fiddle
directly with EH flags. Instead we now recognize -ENOENT means "no port"
and do the handling in the core code.
This also removes an instance of a call to disable the port, and an
identical printk from each driver doing this. Even better - future rule
changes will be in one place only.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The legacy and QDI drivers are ISA/VLB bus [we don't have a VLB define
but ISA will do nicely].
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
We don't currently support pure polled operation so when we meet a BIOS
which forgot to assign an IRQ to a PCI device it all goes a little pear
shaped. Trap this case properly.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Our ATA probe code checks that a device is not reporting a diagnostic
failure during start up. Unfortunately at least one device seems to like
doing this - the Gigabyte iRAM.
This is only done for the master right now (which is fine for the iRAM
as it is SATA), as with PATA some combinations of ATAPI device seem to
fool the check into seeing a drive that isn't there if it is applied to
the slave.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Non-uniform ports handling got broken while updating libata to handle
those in the same host. Only separate irq for the non-uniform
secondary port was implemented while all other fields (host flags,
transfer mode...) of the secondary port simply shared those of the
first.
For ata_piix combined mode, which ATM is the only user of non-uniform
ports, this causes the secondary port assume the wrong type. This can
cause PATA port to use SATA ops, which results in bogus check on PCS
and detection failure.
This patch adds ata_probe_ent->pinfo2 which points to optional
port_info for the secondary port. For the time being, this seems to
be the simplest solution. This workaround will be removed together
with ata_probe_ent itself after init model is updated to allow more
flexibility.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Nelson A. de Oliveira <naoliv@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
A couple of people reported long delays on probe with the newer kernels
and Nvidia PATA. This turned out to be because the Nvidia path forgot to
check the enable bits so probed empty ports.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The vast majority of drivers and changes are from Alan Cox. Albert Lee
contributed and maintains pata_pdc2027x. Adrian Bunk, Andrew Morton,
and Tejun Heo contributed various minor fixes and updates.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The biggest change is that ata_host_set is renamed to ata_host.
* ata_host_set => ata_host
* ata_probe_ent->host_flags => ata_probe_ent->port_flags
* ata_probe_ent->host_set_flags => ata_probe_ent->_host_flags
* ata_host_stats => ata_port_stats
* ata_port->host => ata_port->scsi_host
* ata_port->host_set => ata_port->host
* ata_port_info->host_flags => ata_port_info->flags
* ata_(.*)host_set(.*)\(\) => ata_\1host\2()
The leading underscore in ata_probe_ent->_host_flags is to avoid
reusing ->host_flags for different purpose. Currently, the only user
of the field is libata-bmdma.c and probe_ent itself is scheduled to be
removed.
ata_port->host is reused for different purpose but this field is used
inside libata core proper and of different type.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Remove some code which is unneeded if CONFIG_PM=n.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch adds support for the VIA Technologies VT8237A SATA controller,
used, for example, on the ASUS M2V socket AM2 motherboard.
Signed-off-by: Jay Cliburn <jacliburn@bellsouth.net>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
