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termios parameters
Before setting STOP_TX, set _brkcr to 0 so the SMC does not send a break
character. The driver appears to properly re-initialize _brkcr when the
SMC is restarted.
Do not interrupt RX/TX when the termios is being adjusted; it results in
corrupted characters appearing on the line.
Cc: Vitaly Bordug <vbordug@ru.mvista.com>
Cc: Scott Wood <scottwood@freescale.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Add in console polling hooks for the cpm uart for use with kgdb and
kgdboc.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
CC: galak@kernel.crashing.org
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I missed the cpm_uart one. Thanks to Kumar Gala for reporting it. A double
check found samsung also needed fixing up.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Set port->fifosize to the software FIFO size, and update the port timeout
when the baud rate is modified. SCC ports have an optional 32 byte hardware
FIFO which is currently not taken into account, as there is no documented way
to check when the FIFO becomes empty.
Signed-off-by: Laurent Pinchart <laurentp@cse-semaphore.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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Fix CPM serial port corruption when running with CONFIG_PREEMPT_RT.
Userland usage of console, and kernel printf's were stepping on each others toes.
Also only take lock if not in an oops.
Signed-off-by: Rune Torgersen <runet@innovsys.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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Now that arch/ppc is gone we always define CONFIG_PPC_CPM_NEW_BINDING so
we can remove all the code associated with !CONFIG_PPC_CPM_NEW_BINDING.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This patch allocates parameter RAM for SMC serial ports without relying on
previous initialisation by a boot loader or a wrapper layer.
SMC parameter RAM on CPM2-based platforms can be allocated anywhere in the
general-purpose areas of the dual-port RAM. The current code relies on the
boot loader to allocate a section of general-purpose CPM RAM and gets the
section address from the device tree.
This patch modifies the device tree address usage to reference the SMC
parameter RAM base pointer instead of a pre-allocated RAM section and
allocates memory from the CPM dual-port RAM when initialising the SMC port.
CPM1-based platforms are not affected.
Signed-off-by: Laurent Pinchart <laurentp@cse-semaphore.com>
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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Mostly in and around irq handlers.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: "Luck Tony" <tony.luck@intel.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Cc: Karsten Keil <kkeil@suse.de>
Acked-by: "John W. Linville" <linville@tuxdriver.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: David Brownell <david-b@pacbell.net>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Rename commproc.[ch] to cpm1.[ch] to be more consistent with cpm2. Also
rename cpm2_common.c to cpm2.c as suggested by Scott Wood. Adjust the
includes accordingly.
Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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cpmux is need in all cases, having wrapped by the ifndef CONFIG_STX_GP3
was causing a compile error.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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This patch moves the CPM command handling into commproc.c
for CPM1 and cpm2_common.c. This is yet another preparation
to get rid of drivers accessing the CPM via the global cpmp.
Signed-off-by: Jochen Friedrich <jochen@scram.de>
Acked-by: Scott Wood <scottwood@freescale.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vitaly Bordug <vitb@kernel.crashing.org>
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The way the current CPM binding describes available multi-user (a.k.a.
dual-ported) RAM doesn't work well when there are multiple free regions,
and it doesn't work at all if the region doesn't begin at the start of
the muram area (as the hardware needs to be programmed with offsets into
this area). The latter situation can happen with SMC UARTs on CPM2, as its
parameter RAM is relocatable, u-boot puts it at zero, and the kernel doesn't
support moving it.
It is now described with a muram node, similar to QE. The current CPM
binding is sufficiently recent (i.e. never appeared in an official release)
that compatibility with existing device trees is not an issue.
The code supporting the new binding is shared between cpm1 and cpm2, rather
than remain separated. QE should be able to use this code as well, once
minor fixes are made to its device trees.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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This prevents some bootloader/bootwrapper characters from being lost.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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Mostly a bunch of direct access to in/out conversions, plus a few
cast removals, __iomem annotations, and miscellaneous cleanup.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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is set.
The existing OF glue code was crufty and broken. Rather than fix it,
it has been removed, and the serial driver now talks to the device tree
directly.
The non-CONFIG_PPC_CPM_NEW_BINDING code can go away once CPM platforms
are dropped from arch/ppc (which will hopefully be soon), and existing
arch/powerpc boards that I wasn't able to test on for this patchset get
converted (which should be even sooner).
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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in cpm_uart_cpm1.h, DPRAM_BASE is assigned an address derived from cpmp.
On ARC=ppc, this is a physical address with 1:1 DMA mapping which can't
be used for arithmetric compare operations with virtual addresses
returned by cpm_dpram_addr. This patch changes the assignment to use
cpm_dpram_addr as well, like in cpm_uart_cpm2.h.
Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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cpm_uart_init_portdesc is referenced from non-init code and thus we were
getting the following warning:
WARNING: drivers/built-in.o - Section mismatch: reference to .init.text:cpm_uart_init_portdesc from .text between 'cpm_uart_init' (at offset 0x18020) and 'cpm_uart_drv_remove'
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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This eliminates some warnings.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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The rheap allocation functions return a pointer, but the actual value is based
on how the heap was initialized, and so it can be anything, e.g. an offset
into a buffer. A ulong is a better representation of the value returned by
the allocation functions.
This patch changes all of the relevant rheap functions to use a unsigned long
integers instead of a pointer. In case of an error, the value returned is
a negative error code that has been cast to an unsigned long. The caller can
use the IS_ERR_VALUE() macro to check for this.
All code which calls the rheap functions is updated accordingly. Macros
IS_MURAM_ERR() and IS_DPERR(), have been deleted in favor of IS_ERR_VALUE().
Also added error checking to rh_attach_region().
Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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SPIN_LOCK_UNLOCKED cleanup,use __SPIN_LOCK_UNLOCKED instead
Signed-off-by: Milind Arun Choudhary <milindchoudhary@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fix bug that exists in kernel.org since 2.6.17rc4 - compiles fail if
CONFIG_SERIAL_CPM_SMC is defined. Tested on a board using SMC1 console.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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Recent update of asm-powerpc/io.h caused cpm-related stuff to break in the
current kernel. Current patch fixes it, as well as other inconsistencies
expressed, that do not permit targets from working properly:
- Updated dts with a chosen node with interrupt controller,
- fixed messed device IDs among CPM2 SoC devices,
- corrected odd header name and fixed type in defines,
- Added 82xx subdir to the powerpc/platforms Makefile, missed during
initial commit,
- new solely-powerpc header file for 8260 family (was using one from
arch/ppc, this one cleaned up from the extra stuff), in fact for now
a placeholder to get the board-specific includes for stuff not yet
capable to live with devicetree peeks only
- Fixed couple of misprints in reference mpc8272 dts.
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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This makes cpm uart able to work using OF-passed parameters
in case of CPM stuff (found on most mpc8xx reference and custom
boards). The idea is to keep ppc stuff working yet making it able to be
used for powerpc.
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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The below hunk was missed from the recent patch, and now, there are somewhat
inconsistent definitions:
in cpm_uart.h:
int __init cpm_uart_init_portdesc(void);
in cpm_uart_cpm1.c:
int __init cpm_uart_init_portdesc(void)
{
}
in cpm_uart_cpm2.c:
int cpm_uart_init_portdesc(void)
{
}
Signed-off-by: Kalle Pokki <kalle.pokki@iki.fi>
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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The cpm_uart driver is initialised incorrectly, if there is a frame buffer
console, and CONFIG_SERIAL_CPM_CONSOLE is defined. The driver fails to
call cpm_uart_init_portdesc() and set_lineif() in this case.
Signed-off-by: Kalle Pokki <kalle.pokki@iki.fi>
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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The SMC and SCC hardware transmitter is enabled at the wrong
place. Simply writing twice to the non-console port, like
$ echo asdf > /dev/ttyCPM1
$ echo asdf > /dev/ttyCPM1
puts the shell into endless uninterruptible sleep, since the
transmitter is stopped after the first write, and is not enabled
before the shutdown function of the second write. Thus the transmit
buffers are never emptied.
Signed-off-by: Kalle Pokki <kalle.pokki@iki.fi>
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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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)
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kbuild explicitly includes this at build time.
Signed-off-by: Dave Jones <davej@redhat.com>
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Many files include the filename at the beginning, serveral used a wrong one.
Signed-off-by: Uwe Zeisberger <Uwe_Zeisberger@digi.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
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The fs_no mean used to be fs_enet driver driven, hence it was an
enumeration across all the possible fs_enet "users" in the SoC. Now, with
QE on the pipeline, and to make DTS descriptions more clear, fs_no features
relevant SoC part number, with additional field to describe the SoC type.
Another reason for that is now not only fs_enet is going to utilize those
stuff. There might be UART, HLDC, and even USB, so to prevent confusion and
be ready for upcoming OF_device transfer, fs_enet and cpm_uart drivers were
updated in that concern, as well as the relevant DTS.
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
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Incorporating the new way of cpm2 immr access, introduced in the previous
patch, into CPM2 peripheral devices (fs_enet and cpm_uart). Both ppc and
powerpc approved working( real actions taken in powerpc only, ppc just
has a wrapper to keep init stuff consistent).
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
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The stuff below cleans up the code attempting to remap the whole cpm2_immr
early, as well as places happily assuming that fact. This is more like the 2.4
legacy stuff, and is at least confusing and unclear now.
To keep the world comfortable, a new mechanism is introduced: before accessing
specific immr register/register set, one needs to map it, using cpm2_map(<reg>),
for instance, access to CPM command register will look like
volatile cpm_cpm2_t *cp = cpm2_map(im_cpm);
keeping the code clear, yet without "already defined somewhere" cpm2_immr.
So far, unmapping code is not implemented, but it's not a big deal to add it,
if the whole idea makes sense.
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
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Driver core has been updated to make use of the new powerpc OF-inspired
platform devices, yet keeping compatibility to the vast board list from
ppc.
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
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Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
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This fixes various odd things that missed update together with cpm_uart
platform_device move. Unified resources names, restructurisation, etc.
Also, addressed issue with recent phys/virt translation rework. Being
cache-coherent, CPM2's do alloc_bootmem() for the console stuff, and it was
used to treat console buffer descriptor mapping 1:1 (as in CPM1 case),
which is definitely wrong.
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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A number of small issues are fixed, and added the header file, missed from the
original series. With this, driver should be pretty stable as tested among
both platform-device-driven and "old way" boards. Also added missing GPL
statement , and updated year field on existing ones to reflect
code update.
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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SCC uart sends a break sequence each time it is stopped with the
CPM_CR_STOP_TX command. That means that each time an application closes the
serial device, a break is transmitted. To fix this, graceful tx stop is
issued for SCC.
Signed-off-by: David Jander <david.jander@protonic.nl>
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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Current address translation methods can produce wrong results, because
virt_to_bus and vice versa may not produce correct offsets on dma-allocated
memory. The right way is, while tracking both phys and virt address of the
window that has been allocated for boffer descriptors, and use those
numbers to compute the offset and make translation properly.
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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This is intended to make the driver code more generic and flexible,
to get rid of board-specific layouts within driver, and generic rehaul,
yet keeping compatibility with the existing stuff utilizing it, being
compatible with legacy behavior (but with complaints that legacy mode
used).
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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This replaces old direct usage of tty->flip stuff with relative flip API
calls.
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Convert usage of SERIAL_IO_* to UPIO_*.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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while using SCC as uart and as serial console at same time I got this:
[ 138.214258] Oops: kernel access of bad area, sig: 11 [#1]
[ 138.218832] PREEMPT
[ 138.221021] NIP: C0105C48 LR: C0105E60 SP: C03D5D10 REGS: c03d5c60 TRAP: 0300 Not tainted
[ 138.229280] MSR: 00009032 EE: 1 PR: 0 FP: 0 ME: 1 IR/DR: 11
[ 138.234713] DAR: 00000000, DSISR: C0000000
[ 138.238745] TASK = c0349420[693] 'sh' THREAD: c03d4000
[ 138.243754] Last syscall: 6
[ 138.246402] GPR00: FEFFFFFF C03D5D10 C0349420 C01FB094 00000011 00000000 C1ECFBBC C01F24B0
[ 138.254602] GPR08: FF002820 00000000 FF0028C0 00000000 19133615 A0CBCD5E 02000300 00000000
[ 138.262804] GPR16: 00000000 01FF9E4C 00000000 7FA9A770 00000000 00000000 1003E2A8 00000000
[ 138.271003] GPR24: 100562F4 7F9B6EF4 C0210000 C02A5338 C01FB094 00000000 C01FB094 C1F14574
[ 138.279376] NIP [c0105c48] cpm_uart_tx_pump+0x4c/0x22c
[ 138.284419] LR [c0105e60] cpm_uart_start_tx+0x38/0xb0
[ 138.289361] Call trace:
[ 138.291762] [c0105e60] cpm_uart_start_tx+0x38/0xb0
[ 138.296547] [c010277c] uart_send_xchar+0x88/0x118
[ 138.301244] [c01029a0] uart_unthrottle+0x6c/0x138
[ 138.305942] [c00ece10] check_unthrottle+0x60/0x64
[ 138.310641] [c00ecec4] reset_buffer_flags+0xb0/0x138
[ 138.315595] [c00ecf64] n_tty_flush_buffer+0x18/0x78
[ 138.320465] [c00e81b0] tty_ldisc_flush+0x64/0x7c
[ 138.325078] [c010410c] uart_close+0xf0/0x2c8
[ 138.329348] [c00e9c48] release_dev+0x724/0x8d4
[ 138.333790] [c00e9e18] tty_release+0x20/0x3c
[ 138.338061] [c006e544] __fput+0x178/0x1e0
[ 138.342076] [c006c43c] filp_close+0x54/0xac
[ 138.346261] [c0002d90] ret_from_syscall+0x0/0x44
[ 138.352386] note: sh[693] exited with preempt_count 2
a easy way to reproduce it is log into the system using ssh and do:
cat >/dev/ttyCPM0
then, switch to minicom and write some stuff on it back to ssh, a control C
produce the oops
this happens because uart_close calls uart_shutdown which frees xmit.buf,
currently used by xchar sending in cpm_uart_tx_pump(), which seems wrong.
the attached patch fixes the oops and also fixes xchar sending.
Signed-off-by: Paul Mackerras <paulus@samba.org>
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Changed jobs and the Freescale address is no longer valid.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Base addess register for SMC 1 and 2 are never initialized. This means
that they will not work unless a bootloader already configured them.
The DPRAM already have space reserved, this patch just makes sure the base
addess register is updated correctly on initialization.
Signed-off-by: Rune Torgersen <runet@innovsys.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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use schedule_timeout instead of direct call to schedule
Signed-off-by: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The 2nd serial port on the MPC8560 ADS was not being configured correctly
and thus could not be used as a console. Updated the defconfig for the
board to configure the proper SCC channel for the 2nd serial port.
Signed-off-by: Roy Zang <tie-fei.zang@freescale.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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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>
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