Commit 4ba66a97 authored by Arnd Bergmann's avatar Arnd Bergmann

arch: remove blackfin port

The Analog Devices Blackfin port was added in 2007 and was rather
active for a while, but all work on it has come to a standstill
over time, as Analog have changed their product line-up.

Aaron Wu confirmed that the architecture port is no longer relevant,
and multiple people suggested removing blackfin independently because
of some of its oddities like a non-working SMP port, and the amount of
duplication between the chip variants, which cause extra work when
doing cross-architecture changes.

Link: https://docs.blackfin.uclinux.org/Acked-by: default avatarAaron Wu <Aaron.Wu@analog.com>
Acked-by: Bryan Wu's avatarBryan Wu <cooloney@gmail.com>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Mike Frysinger <vapier@chromium.org>
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
parent b8c9c8f0
......@@ -66,8 +66,6 @@ backlight/
- directory with info on controlling backlights in flat panel displays
bcache.txt
- Block-layer cache on fast SSDs to improve slow (raid) I/O performance.
blackfin/
- directory with documentation for the Blackfin arch.
block/
- info on the Block I/O (BIO) layer.
blockdev/
......
......@@ -89,7 +89,6 @@ parameter is applicable::
APM Advanced Power Management support is enabled.
ARM ARM architecture is enabled.
AX25 Appropriate AX.25 support is enabled.
BLACKFIN Blackfin architecture is enabled.
CLK Common clock infrastructure is enabled.
CMA Contiguous Memory Area support is enabled.
DRM Direct Rendering Management support is enabled.
......
......@@ -1025,7 +1025,7 @@
address. The serial port must already be setup
and configured. Options are not yet supported.
earlyprintk= [X86,SH,BLACKFIN,ARM,M68k,S390]
earlyprintk= [X86,SH,ARM,M68k,S390]
earlyprintk=vga
earlyprintk=efi
earlyprintk=sclp
......
00-INDEX
- This file
bfin-gpio-notes.txt
- Notes in developing/using bfin-gpio driver.
bfin-spi-notes.txt
- Notes for using bfin spi bus driver.
/*
* File: Documentation/blackfin/bfin-gpio-notes.txt
* Based on:
* Author:
*
* Created: $Id: bfin-gpio-note.txt 2008-11-24 16:42 grafyang $
* Description: This file contains the notes in developing/using bfin-gpio.
*
*
* Rev:
*
* Modified:
* Copyright 2004-2008 Analog Devices Inc.
*
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
*/
1. Blackfin GPIO introduction
There are many GPIO pins on Blackfin. Most of these pins are muxed to
multi-functions. They can be configured as peripheral, or just as GPIO,
configured to input with interrupt enabled, or output.
For detailed information, please see "arch/blackfin/kernel/bfin_gpio.c",
or the relevant HRM.
2. Avoiding resource conflict
Followed function groups are used to avoiding resource conflict,
- Use the pin as peripheral,
int peripheral_request(unsigned short per, const char *label);
int peripheral_request_list(const unsigned short per[], const char *label);
void peripheral_free(unsigned short per);
void peripheral_free_list(const unsigned short per[]);
- Use the pin as GPIO,
int bfin_gpio_request(unsigned gpio, const char *label);
void bfin_gpio_free(unsigned gpio);
- Use the pin as GPIO interrupt,
int bfin_gpio_irq_request(unsigned gpio, const char *label);
void bfin_gpio_irq_free(unsigned gpio);
The request functions will record the function state for a certain pin,
the free functions will clear its function state.
Once a pin is requested, it can't be requested again before it is freed by
previous caller, otherwise kernel will dump stacks, and the request
function fail.
These functions are wrapped by other functions, most of the users need not
care.
3. But there are some exceptions
- Kernel permit the identical GPIO be requested both as GPIO and GPIO
interrupt.
Some drivers, like gpio-keys, need this behavior. Kernel only print out
warning messages like,
bfin-gpio: GPIO 24 is already reserved by gpio-keys: BTN0, and you are
configuring it as IRQ!
Note: Consider the case that, if there are two drivers need the
identical GPIO, one of them use it as GPIO, the other use it as
GPIO interrupt. This will really cause resource conflict. So if
there is any abnormal driver behavior, please check the bfin-gpio
warning messages.
- Kernel permit the identical GPIO be requested from the same driver twice.
SPI Chip Select behavior:
With the Blackfin on-chip SPI peripheral, there is some logic tied to the CPHA
bit whether the Slave Select Line is controlled by hardware (CPHA=0) or
controlled by software (CPHA=1). However, the Linux SPI bus driver assumes that
the Slave Select is always under software control and being asserted during
the entire SPI transfer. - And not just bits_per_word duration.
In most cases you can utilize SPI MODE_3 instead of MODE_0 to work-around this
behavior. If your SPI slave device in question requires SPI MODE_0 or MODE_2
timing, you can utilize the GPIO controlled SPI Slave Select option instead.
In this case, you should use GPIO based CS for all of your slaves and not just
the ones using mode 0 or 2 in order to guarantee correct CS toggling behavior.
You can even use the same pin whose peripheral role is a SSEL,
but use it as a GPIO instead.
......@@ -2629,51 +2629,6 @@ F: Documentation/filesystems/bfs.txt
F: fs/bfs/
F: include/uapi/linux/bfs_fs.h
BLACKFIN ARCHITECTURE
L: adi-buildroot-devel@lists.sourceforge.net (moderated for non-subscribers)
T: git git://git.code.sf.net/p/adi-linux/code
W: http://blackfin.uclinux.org
S: Orphan
F: arch/blackfin/
BLACKFIN EMAC DRIVER
L: adi-buildroot-devel@lists.sourceforge.net (moderated for non-subscribers)
W: http://blackfin.uclinux.org
S: Orphan
F: drivers/net/ethernet/adi/
BLACKFIN MEDIA DRIVER
L: adi-buildroot-devel@lists.sourceforge.net (moderated for non-subscribers)
W: http://blackfin.uclinux.org/
S: Orphan
F: drivers/media/platform/blackfin/
F: drivers/media/i2c/adv7183*
F: drivers/media/i2c/vs6624*
BLACKFIN RTC DRIVER
L: adi-buildroot-devel@lists.sourceforge.net (moderated for non-subscribers)
W: http://blackfin.uclinux.org
S: Orphan
F: drivers/rtc/rtc-bfin.c
BLACKFIN SDH DRIVER
L: adi-buildroot-devel@lists.sourceforge.net (moderated for non-subscribers)
W: http://blackfin.uclinux.org
S: Orphan
F: drivers/mmc/host/bfin_sdh.c
BLACKFIN SERIAL DRIVER
L: adi-buildroot-devel@lists.sourceforge.net (moderated for non-subscribers)
W: http://blackfin.uclinux.org
S: Orphan
F: drivers/tty/serial/bfin_uart.c
BLACKFIN WATCHDOG DRIVER
L: adi-buildroot-devel@lists.sourceforge.net (moderated for non-subscribers)
W: http://blackfin.uclinux.org
S: Orphan
F: drivers/watchdog/bfin_wdt.c
BLINKM RGB LED DRIVER
M: Jan-Simon Moeller <jansimon.moeller@gmx.de>
S: Maintained
......
The Clear BSD license:
Copyright (c) 2012, Analog Devices, Inc. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted (subject to the limitations in the
disclaimer below) provided that the following conditions are met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the
distribution.
* Neither the name of Analog Devices, Inc. nor the names of its
contributors may be used to endorse or promote products derived
from this software without specific prior written permission.
NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE
GRANTED BY THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT
HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
This diff is collapsed.
# SPDX-License-Identifier: GPL-2.0
menu "Kernel hacking"
source "lib/Kconfig.debug"
config DEBUG_VERBOSE
bool "Verbose fault messages"
default y
select PRINTK
help
When a program crashes due to an exception, or the kernel detects
an internal error, the kernel can print a not so brief message
explaining what the problem was. This debugging information is
useful to developers and kernel hackers when tracking down problems,
but mostly meaningless to other people. This is always helpful for
debugging but serves no purpose on a production system.
Most people should say N here.
config DEBUG_MMRS
tristate "Generate Blackfin MMR tree"
depends on !PINCTRL
select DEBUG_FS
help
Create a tree of Blackfin MMRs via the debugfs tree. If
you enable this, you will find all MMRs laid out in the
/sys/kernel/debug/blackfin/ directory where you can read/write
MMRs directly from userspace. This is obviously just a debug
feature.
config DEBUG_HWERR
bool "Hardware error interrupt debugging"
depends on DEBUG_KERNEL
help
When enabled, the hardware error interrupt is never disabled, and
will happen immediately when an error condition occurs. This comes
at a slight cost in code size, but is necessary if you are getting
hardware error interrupts and need to know where they are coming
from.
config EXACT_HWERR
bool "Try to make Hardware errors exact"
depends on DEBUG_HWERR
help
By default, the Blackfin hardware errors are not exact - the error
be reported multiple cycles after the error happens. This delay
can cause the wrong application, or even the kernel to receive a
signal to be killed. If you are getting HW errors in your system,
try turning this on to ensure they are at least coming from the
proper thread.
On production systems, it is safe (and a small optimization) to say N.
config DEBUG_DOUBLEFAULT
bool "Debug Double Faults"
default n
help
If an exception is caused while executing code within the exception
handler, the NMI handler, the reset vector, or in emulator mode,
a double fault occurs. On the Blackfin, this is a unrecoverable
event. You have two options:
- RESET exactly when double fault occurs. The excepting
instruction address is stored in RETX, where the next kernel
boot will print it out.
- Print debug message. This is much more error prone, although
easier to handle. It is error prone since:
- The excepting instruction is not committed.
- All writebacks from the instruction are prevented.
- The generated exception is not taken.
- The EXCAUSE field is updated with an unrecoverable event
The only way to check this is to see if EXCAUSE contains the
unrecoverable event value at every exception return. By selecting
this option, you are skipping over the faulting instruction, and
hoping things stay together enough to print out a debug message.
This does add a little kernel code, but is the only method to debug
double faults - if unsure say "Y"
choice
prompt "Double Fault Failure Method"
default DEBUG_DOUBLEFAULT_PRINT
depends on DEBUG_DOUBLEFAULT
config DEBUG_DOUBLEFAULT_PRINT
bool "Print"
config DEBUG_DOUBLEFAULT_RESET
bool "Reset"
endchoice
config DEBUG_HUNT_FOR_ZERO
bool "Catch NULL pointer reads/writes"
default y
help
Say Y here to catch reads/writes to anywhere in the memory range
from 0x0000 - 0x0FFF (the first 4k) of memory. This is useful in
catching common programming errors such as NULL pointer dereferences.
Misbehaving applications will be killed (generate a SEGV) while the
kernel will trigger a panic.
Enabling this option will take up an extra entry in CPLB table.
Otherwise, there is no extra overhead.
config DEBUG_BFIN_HWTRACE_ON
bool "Turn on Blackfin's Hardware Trace"
default y
help
All Blackfins include a Trace Unit which stores a history of the last
16 changes in program flow taken by the program sequencer. The history
allows the user to recreate the program sequencer’s recent path. This
can be handy when an application dies - we print out the execution
path of how it got to the offending instruction.
By turning this off, you may save a tiny amount of power.
choice
prompt "Omit loop Tracing"
default DEBUG_BFIN_HWTRACE_COMPRESSION_OFF
depends on DEBUG_BFIN_HWTRACE_ON
help
The trace buffer can be configured to omit recording of changes in
program flow that match either the last entry or one of the last
two entries. Omitting one of these entries from the record prevents
the trace buffer from overflowing because of any sort of loop (for, do
while, etc) in the program.
Because zero-overhead Hardware loops are not recorded in the trace buffer,
this feature can be used to prevent trace overflow from loops that
are nested four deep.
config DEBUG_BFIN_HWTRACE_COMPRESSION_OFF
bool "Trace all Loops"
help
The trace buffer records all changes of flow
config DEBUG_BFIN_HWTRACE_COMPRESSION_ONE
bool "Compress single-level loops"
help
The trace buffer does not record single loops - helpful if trace
is spinning on a while or do loop.
config DEBUG_BFIN_HWTRACE_COMPRESSION_TWO
bool "Compress two-level loops"
help
The trace buffer does not record loops two levels deep. Helpful if
the trace is spinning in a nested loop
endchoice
config DEBUG_BFIN_HWTRACE_COMPRESSION
int
depends on DEBUG_BFIN_HWTRACE_ON
default 0 if DEBUG_BFIN_HWTRACE_COMPRESSION_OFF
default 1 if DEBUG_BFIN_HWTRACE_COMPRESSION_ONE
default 2 if DEBUG_BFIN_HWTRACE_COMPRESSION_TWO
config DEBUG_BFIN_HWTRACE_EXPAND
bool "Expand Trace Buffer greater than 16 entries"
depends on DEBUG_BFIN_HWTRACE_ON
default n
help
By selecting this option, every time the 16 hardware entries in
the Blackfin's HW Trace buffer are full, the kernel will move them
into a software buffer, for dumping when there is an issue. This
has a great impact on performance, (an interrupt every 16 change of
flows) and should normally be turned off, except in those nasty
debugging sessions
config DEBUG_BFIN_HWTRACE_EXPAND_LEN
int "Size of Trace buffer (in power of 2k)"
range 0 4
depends on DEBUG_BFIN_HWTRACE_EXPAND
default 1
help
This sets the size of the software buffer that the trace information
is kept in.
0 for (2^0) 1k, or 256 entries,
1 for (2^1) 2k, or 512 entries,
2 for (2^2) 4k, or 1024 entries,
3 for (2^3) 8k, or 2048 entries,
4 for (2^4) 16k, or 4096 entries
config DEBUG_BFIN_NO_KERN_HWTRACE
bool "Turn off hwtrace in CPLB handlers"
depends on DEBUG_BFIN_HWTRACE_ON
default y
help
The CPLB error handler contains a lot of flow changes which can
quickly fill up the hardware trace buffer. When debugging crashes,
the hardware trace may indicate that the problem lies in kernel
space when in reality an application is buggy.
Say Y here to disable hardware tracing in some known "jumpy" pieces
of code so that the trace buffer will extend further back.
config EARLY_PRINTK
bool "Early printk"
default n
select SERIAL_CORE_CONSOLE
help
This option enables special console drivers which allow the kernel
to print messages very early in the bootup process.
This is useful for kernel debugging when your machine crashes very
early before the console code is initialized. After enabling this
feature, you must add "earlyprintk=serial,uart0,57600" to the
command line (bootargs). It is safe to say Y here in all cases, as
all of this lives in the init section and is thrown away after the
kernel boots completely.
config NMI_WATCHDOG
bool "Enable NMI watchdog to help debugging lockup on SMP"
default n
depends on SMP
help
If any CPU in the system does not execute the period local timer
interrupt for more than 5 seconds, then the NMI handler dumps debug
information. This information can be used to debug the lockup.
config CPLB_INFO
bool "Display the CPLB information"
help
Display the CPLB information via /proc/cplbinfo.
config ACCESS_CHECK
bool "Check the user pointer address"
default y
help
Usually the pointer transfer from user space is checked to see if its
address is in the kernel space.
Say N here to disable that check to improve the performance.
config BFIN_ISRAM_SELF_TEST
bool "isram boot self tests"
default n
help
Run some self tests of the isram driver code at boot.
config BFIN_PSEUDODBG_INSNS
bool "Support pseudo debug instructions"
default n
help
This option allows the kernel to emulate some pseudo instructions which
allow simulator test cases to be run under Linux with no changes.
Most people should say N here.
config BFIN_PM_WAKEUP_TIME_BENCH
bool "Display the total time for kernel to resume from power saving mode"
default n
help
Display the total time when kernel resumes normal from standby or
suspend to mem mode.
endmenu
#
# arch/blackfin/Makefile
#
# This file is subject to the terms and conditions of the GNU General Public
# License. See the file "COPYING" in the main directory of this archive
# for more details.
#
ifeq ($(CROSS_COMPILE),)
CROSS_COMPILE := bfin-uclinux-
endif
LDFLAGS_vmlinux := -X
OBJCOPYFLAGS := -O binary -R .note -R .comment -S
GZFLAGS := -9
KBUILD_CFLAGS += $(call cc-option,-mno-fdpic)
ifeq ($(CONFIG_ROMKERNEL),y)
KBUILD_CFLAGS += -mlong-calls
endif
KBUILD_AFLAGS += $(call cc-option,-mno-fdpic)
KBUILD_CFLAGS_MODULE += -mlong-calls
LDFLAGS += -m elf32bfin
KBUILD_DEFCONFIG := BF537-STAMP_defconfig
# setup the machine name and the machine dependent settings
machine-$(CONFIG_BF512) := bf518
machine-$(CONFIG_BF514) := bf518
machine-$(CONFIG_BF516) := bf518
machine-$(CONFIG_BF518) := bf518
machine-$(CONFIG_BF522) := bf527
machine-$(CONFIG_BF523) := bf527
machine-$(CONFIG_BF524) := bf527
machine-$(CONFIG_BF525) := bf527
machine-$(CONFIG_BF526) := bf527
machine-$(CONFIG_BF527) := bf527
machine-$(CONFIG_BF531) := bf533
machine-$(CONFIG_BF532) := bf533
machine-$(CONFIG_BF533) := bf533
machine-$(CONFIG_BF534) := bf537
machine-$(CONFIG_BF536) := bf537
machine-$(CONFIG_BF537) := bf537
machine-$(CONFIG_BF538) := bf538
machine-$(CONFIG_BF539) := bf538
machine-$(CONFIG_BF542) := bf548
machine-$(CONFIG_BF542M) := bf548
machine-$(CONFIG_BF544) := bf548