summaryrefslogtreecommitdiffstats
path: root/drivers/serial/pmac_zilog.c
Commit message (Collapse)AuthorAgeFilesLines
* IRQ: Maintain regs pointer globally rather than passing to IRQ handlersDavid Howells2006-10-051-9/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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)
* [POWERPC] powermac: Constify & voidify get_property()Jeremy Kerr2006-07-311-4/+5
| | | | | | | | | | | | | Now that get_property() returns a void *, there's no need to cast its return value. Also, treat the return value as const, so we can constify get_property later. powermac platform & macintosh driver changes. Built for pmac32_defconfig, g5_defconfig Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
* [POWERPC] Add new interrupt mapping core and change platforms to use itBenjamin Herrenschmidt2006-07-031-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds the new irq remapper core and removes the old one. Because there are some fundamental conflicts with the old code, like the value of NO_IRQ which I'm now setting to 0 (as per discussions with Linus), etc..., this commit also changes the relevant platform and driver code over to use the new remapper (so as not to cause difficulties later in bisecting). This patch removes the old pre-parsing of the open firmware interrupt tree along with all the bogus assumptions it made to try to renumber interrupts according to the platform. This is all to be handled by the new code now. For the pSeries XICS interrupt controller, a single remapper host is created for the whole machine regardless of how many interrupt presentation and source controllers are found, and it's set to match any device node that isn't a 8259. That works fine on pSeries and avoids having to deal with some of the complexities of split source controllers vs. presentation controllers in the pSeries device trees. The powerpc i8259 PIC driver now always requests the legacy interrupt range. It also has the feature of being able to match any device node (including NULL) if passed no device node as an input. That will help porting over platforms with broken device-trees like Pegasos who don't have a proper interrupt tree. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
* [PATCH] irq-flags: serial: Use the new IRQF_ constantsThomas Gleixner2006-07-021-1/+1
| | | | | | | | | | Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Remove obsolete #include <linux/config.h>Jörn Engel2006-06-301-1/+0
| | | | | Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [PATCH] devfs: Remove devfs support from the serial subsystemGreg Kroah-Hartman2006-06-261-1/+0
| | | | | | Also fixes all serial drivers. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [SERIAL] kernel console should send CRLF not LFCRRussell King2006-03-201-12/+11
| | | | | | | | | | | Glen Turner reported that writing LFCR rather than the more traditional CRLF causes issues with some terminals. Since this aflicts many serial drivers, extract the common code to a library function (uart_console_write) and arrange for each driver to supply a "putchar" function. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [SERIAL] uart_port iotype member should use UPIO_*Russell King2006-02-051-1/+1
| | | | | | Convert usage of SERIAL_IO_* to UPIO_*. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [SERIAL] convert uart_state.sem to uart_state.mutexIngo Molnar2006-01-131-5/+4
| | | | | | | | | | | | semaphore to mutex conversion. the conversion was generated via scripts, and the result was validated automatically via a script as well. build and boot tested. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [SERIAL] turn serial semaphores into mutexesArjan van de Ven2006-01-121-11/+12
| | | | | | | Turn several drivers/serial/ semaphores-used-as-mutex into mutexes Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [PATCH] TTY layer buffering revampAlan Cox2006-01-101-31/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The API and code have been through various bits of initial review by serial driver people but they definitely need to live somewhere for a while so the unconverted drivers can get knocked into shape, existing drivers that have been updated can be better tuned and bugs whacked out. This replaces the tty flip buffers with kmalloc objects in rings. In the normal situation for an IRQ driven serial port at typical speeds the behaviour is pretty much the same, two buffers end up allocated and the kernel cycles between them as before. When there are delays or at high speed we now behave far better as the buffer pool can grow a bit rather than lose characters. This also means that we can operate at higher speeds reliably. For drivers that receive characters in blocks (DMA based, USB and especially virtualisation) the layer allows a lot of driver specific code that works around the tty layer with private secondary queues to be removed. The IBM folks need this sort of layer, the smart serial port people do, the virtualisers do (because a virtualised tty typically operates at infinite speed rather than emulating 9600 baud). Finally many drivers had invalid and unsafe attempts to avoid buffer overflows by directly invoking tty methods extracted out of the innards of work queue structs. These are no longer needed and all go away. That fixes various random hangs with serial ports on overflow. The other change in here is to optimise the receive_room path that is used by some callers. It turns out that only one ldisc uses receive room except asa constant and it updates it far far less than the value is read. We thus make it a variable not a function call. I expect the code to contain bugs due to the size alone but I'll be watching and squashing them and feeding out new patches as it goes. Because the buffers now dynamically expand you should only run out of buffering when the kernel runs out of memory for real. That means a lot of the horrible hacks high performance drivers used to do just aren't needed any more. Description: tty_insert_flip_char is an old API and continues to work as before, as does tty_flip_buffer_push() [this is why many drivers dont need modification]. It does now also return the number of chars inserted There are also tty_buffer_request_room(tty, len) which asks for a buffer block of the length requested and returns the space found. This improves efficiency with hardware that knows how much to transfer. and tty_insert_flip_string_flags(tty, str, flags, len) to insert a string of characters and flags For a smart interface the usual code is len = tty_request_buffer_room(tty, amount_hardware_says); tty_insert_flip_string(tty, buffer_from_card, len); More description! At the moment tty buffers are attached directly to the tty. This is causing a lot of the problems related to tty layer locking, also problems at high speed and also with bursty data (such as occurs in virtualised environments) I'm working on ripping out the flip buffers and replacing them with a pool of dynamically allocated buffers. This allows both for old style "byte I/O" devices and also helps virtualisation and smart devices where large blocks of data suddenely materialise and need storing. So far so good. Lots of drivers reference tty->flip.*. Several of them also call directly and unsafely into function pointers it provides. This will all break. Most drivers can use tty_insert_flip_char which can be kept as an API but others need more. At the moment I've added the following interfaces, if people think more will be needed now is a good time to say int tty_buffer_request_room(tty, size) Try and ensure at least size bytes are available, returns actual room (may be zero). At the moment it just uses the flipbuf space but that will change. Repeated calls without characters being added are not cumulative. (ie if you call it with 1, 1, 1, and then 4 you'll have four characters of space. The other functions will also try and grow buffers in future but this will be a more efficient way when you know block sizes. int tty_insert_flip_char(tty, ch, flag) As before insert a character if there is room. Now returns 1 for success, 0 for failure. int tty_insert_flip_string(tty, str, len) Insert a block of non error characters. Returns the number inserted. int tty_prepare_flip_string(tty, strptr, len) Adjust the buffer to allow len characters to be added. Returns a buffer pointer in strptr and the length available. This allows for hardware that needs to use functions like insl or mencpy_fromio. Signed-off-by: Alan Cox <alan@redhat.com> Cc: Paul Fulghum <paulkf@microgate.com> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] powerpc: Remove device_node addrs/n_addrBenjamin Herrenschmidt2006-01-091-4/+11
| | | | | | | | | | | | The pre-parsed addrs/n_addrs fields in struct device_node are finally gone. Remove the dodgy heuristics that did that parsing at boot and remove the fields themselves since we now have a good replacement with the new OF parsing code. This patch also fixes a bunch of drivers to use the new code instead, so that at least pmac32, pseries, iseries and g5 defconfigs build. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
* [PATCH] swsusp: switch pm_message_t to structPavel Machek2005-09-051-3/+3
| | | | | | | | | | | | | | This adds type-checking to pm_message_t, so that people can't confuse it with int or u32. It also allows us to fix "disk yoyo" during suspend (disk spinning down/up/down). [We've tried that before; since that cpufreq problems were fixed and I've tried make allyes config and fixed resulting damage.] Signed-off-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Alexander Nyberg <alexn@telia.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [SERIAL] Clean up and fix tty transmission start/stopingRussell King2005-08-311-4/+3
| | | | | | | | | | | | | | | | | | | | | | | The start_tx and stop_tx methods were passed a flag to indicate whether the start/stop was from the tty start/stop callbacks, and some drivers used this flag to decide whether to ask the UART to immediately stop transmission (where the UART supports such a feature.) There are other cases when we wish this to occur - when CTS is lowered, or if we change from soft to hard flow control and CTS is inactive. In these cases, this flag was false, and we would allow the transmitter to drain before stopping. There is really only one case where we want to let the transmitter drain before disabling, and that's when we run out of characters to send. Hence, re-jig the start_tx and stop_tx methods to eliminate this flag, and introduce new functions for the special "disable and allow transmitter to drain" case. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [PATCH] openfirmware: generate device table for userspaceJeff Mahoney2005-07-061-6/+3
| | | | | | | | | | | | | | | | This converts the usage of struct of_match to struct of_device_id, similar to pci_device_id. This allows a device table to be generated, which can be parsed by depmod(8) to generate a map file for module loading. In order for hotplug to work with macio devices, patches to module-init-tools and hotplug must be applied. Those patches are available at: ftp://ftp.suse.com/pub/people/jeffm/linux/macio-hotplug/ Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Serial: Adjust serial lockingRussell King2005-06-291-2/+2
| | | | | | | | This patch changes the way serial ports are locked when getting modem status. This change is necessary because we will need to atomically read the modem status and take action depending on the CTS status. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [PATCH] fix u32 vs. pm_message_t in drivers/Pavel Machek2005-04-161-1/+1
| | | | | | | | -rc2-mm1 still contains few places where u32 and pm_message_t. This fixes drivers/serial [should change no code]. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+2048
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
OpenPOWER on IntegriCloud