path: root/Documentation/arm
diff options
authorRussell King <rmk+kernel@arm.linux.org.uk>2011-01-21 11:04:45 +0000
committerRussell King <rmk+kernel@arm.linux.org.uk>2011-01-24 19:05:19 +0000
commit82e6923e1862428b755ec306b3dbccf926849314 (patch)
treee0be095c30c7cbfeff2a2096cf53e9c2f92fed13 /Documentation/arm
parent1bae4ce27c9c90344f23c65ea6966c50ffeae2f5 (diff)
ARM: lh7a40x: remove unmaintained platform support
lh7a40x has only been receiving updates for updates to generic code. The last involvement from the maintainer according to the git logs was in 2006. As such, it is a maintainence burden with no benefit. This gets rid of two defconfigs. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'Documentation/arm')
9 files changed, 0 insertions, 367 deletions
diff --git a/Documentation/arm/Sharp-LH/ADC-LH7-Touchscreen b/Documentation/arm/Sharp-LH/ADC-LH7-Touchscreen
deleted file mode 100644
index dc460f05564..00000000000
--- a/Documentation/arm/Sharp-LH/ADC-LH7-Touchscreen
+++ /dev/null
@@ -1,61 +0,0 @@
-README on the ADC/Touchscreen Controller
-The LH79524 and LH7A404 include a built-in Analog to Digital
-controller (ADC) that is used to process input from a touchscreen.
-The driver only implements a four-wire touch panel protocol.
-The touchscreen driver is maintenance free except for the pen-down or
-touch threshold. Some resistive displays and board combinations may
-require tuning of this threshold. The driver exposes some of its
-internal state in the sys filesystem. If the kernel is configured
-with it, CONFIG_SYSFS, and sysfs is mounted at /sys, there will be a
- /sys/devices/platform/adc-lh7.0
-containing these files.
- -r--r--r-- 1 root root 4096 Jan 1 00:00 samples
- -rw-r--r-- 1 root root 4096 Jan 1 00:00 threshold
- -r--r--r-- 1 root root 4096 Jan 1 00:00 threshold_range
-The threshold is the current touch threshold. It defaults to 750 on
-most targets.
- # cat threshold
- 750
-The threshold_range contains the range of valid values for the
-threshold. Values outside of this range will be silently ignored.
- # cat threshold_range
- 0 1023
-To change the threshold, write a value to the threshold file.
- # echo 500 > threshold
- # cat threshold
- 500
-The samples file contains the most recently sampled values from the
-ADC. There are 12. Below are typical of the last sampled values when
-the pen has been released. The first two and last two samples are for
-detecting whether or not the pen is down. The third through sixth are
-X coordinate samples. The seventh through tenth are Y coordinate
- # cat samples
- 1023 1023 0 0 0 0 530 529 530 529 1023 1023
-To determine a reasonable threshold, press on the touch panel with an
-appropriate stylus and read the values from samples.
- # cat samples
- 1023 676 92 103 101 102 855 919 922 922 1023 679
-The first and eleventh samples are discarded. Thus, the important
-values are the second and twelfth which are used to determine if the
-pen is down. When both are below the threshold, the driver registers
-that the pen is down. When either is above the threshold, it
-registers then pen is up.
diff --git a/Documentation/arm/Sharp-LH/CompactFlash b/Documentation/arm/Sharp-LH/CompactFlash
deleted file mode 100644
index 8616d877df9..00000000000
--- a/Documentation/arm/Sharp-LH/CompactFlash
+++ /dev/null
@@ -1,32 +0,0 @@
-README on the Compact Flash for Card Engines
-There are three challenges in supporting the CF interface of the Card
-Engines. First, every IO operation must be followed with IO to
-another memory region. Second, the slot is wired for one-to-one
-address mapping *and* it is wired for 16 bit access only. Second, the
-interrupt request line from the CF device isn't wired.
-The IOBARRIER issue is covered in README.IOBARRIER. This isn't an
-onerous problem. Enough said here.
-The addressing issue is solved in the
-arch/arm/mach-lh7a40x/ide-lpd7a40x.c file with some awkward
-work-arounds. We implement a special SELECT_DRIVE routine that is
-called before the IDE driver performs its own SELECT_DRIVE. Our code
-recognizes that the SELECT register cannot be modified without also
-writing a command. It send an IDLE_IMMEDIATE command on selecting a
-drive. The function also prevents drive select to the slave drive
-since there can be only one. The awkward part is that the IDE driver,
-even though we have a select procedure, also attempts to change the
-drive by writing directly the SELECT register. This attempt is
-explicitly blocked by the OUTB function--not pretty, but effective.
-The lack of interrupts is a more serious problem. Even though the CF
-card is fast when compared to a normal IDE device, we don't know that
-the CF is really flash. A user could use one of the very small hard
-drives being shipped with a CF interface. The IDE code includes a
-check for interfaces that lack an IRQ. In these cases, submitting a
-command to the IDE controller is followed by a call to poll for
-completion. If the device isn't immediately ready, it schedules a
-timer to poll again later.
diff --git a/Documentation/arm/Sharp-LH/IOBarrier b/Documentation/arm/Sharp-LH/IOBarrier
deleted file mode 100644
index 2e953e228f4..00000000000
--- a/Documentation/arm/Sharp-LH/IOBarrier
+++ /dev/null
@@ -1,45 +0,0 @@
-README on the IOBARRIER for CardEngine IO
-Due to an unfortunate oversight when the Card Engines were designed,
-the signals that control access to some peripherals, most notably the
-SMC91C9111 ethernet controller, are not properly handled.
-The symptom is that some back to back IO with the peripheral returns
-unreliable data. With the SMC chip, you'll see errors about the bank
-register being 'screwed'.
-The cause is that the AEN signal to the SMC chip does not transition
-for every memory access. It is driven through the CPLD from the CS7
-line of the CPU's static memory controller which is optimized to
-eliminate unnecessary transitions. Yet, the SMC requires a transition
-for every write access. The Sharp website has more information about
-the effect this power-conserving feature has on peripheral
-The solution is to follow every write access to the SMC chip with an
-access to another memory region that will force the CPU to release the
-chip select line. It is important to guarantee that this access
-forces the CPU off-chip. We map a page of SDRAM as if it were an
-uncacheable IO device and read from it after every SMC IO write
-Only this sequence is important. It does not matter that there is no
-BARRIER IO before the access to the SMC chip because the AEN latch
-only needs occurs after the SMC IO write cycle. The routines that
-implement this work-around make an additional concession which is to
-disable interrupts during the IO sequence. Other hardware devices
-(the LogicPD CPLD) have registers in the same physical memory
-region as the SMC chip. An interrupt might allow an access to one of
-those registers while SMC IO is being performed.
-You might be tempted to think that we have to access another device
-attached to the static memory controller, but the empirical evidence
-indicates that this is not so. Mapping 0x00000000 (flash) and
-0xc0000000 (SDRAM) appear to have the same effect. Using SDRAM seems
-to be faster. Choosing to access an undecoded memory region is not
-desirable as there is no way to know how that chip select will be used
-in the future.
diff --git a/Documentation/arm/Sharp-LH/KEV7A400 b/Documentation/arm/Sharp-LH/KEV7A400
deleted file mode 100644
index be32b14cd53..00000000000
--- a/Documentation/arm/Sharp-LH/KEV7A400
+++ /dev/null
@@ -1,8 +0,0 @@
-README on Implementing Linux for Sharp's KEV7a400
-This product has been discontinued by Sharp. For the time being, the
-partially implemented code remains in the kernel. At some point in
-the future, either the code will be finished or it will be removed
-completely. This depends primarily on how many of the development
-boards are in the field.
diff --git a/Documentation/arm/Sharp-LH/LCDPanels b/Documentation/arm/Sharp-LH/LCDPanels
deleted file mode 100644
index fb1b21c2f2f..00000000000
--- a/Documentation/arm/Sharp-LH/LCDPanels
+++ /dev/null
@@ -1,59 +0,0 @@
-README on the LCD Panels
-Configuration options for several LCD panels, available from Logic PD,
-are included in the kernel source. This README will help you
-understand the configuration data and give you some guidance for
-adding support for other panels if you wish.
-There is no way, at present, to detect which panel is attached to the
-system at runtime. Thus the kernel configuration is static. The file
-arch/arm/mach-ld7a40x/lcd-panels.h (or similar) defines all of the
-panel specific parameters.
-It should be possible for this data to be shared among several device
-families. The current layout may be insufficiently general, but it is
-amenable to improvement.
-The panel data sheets will give a range of acceptable pixel clocks.
-The fundamental LCDCLK input frequency is divided down by a PCD
-constant in field '.tim2'. It may happen that it is impossible to set
-the pixel clock within this range. A clock which is too slow will
-tend to flicker. For the highest quality image, set the clock as high
-as possible.
-These values may be difficult to glean from the panel data sheet. In
-the case of the Sharp panels, the upper margin is explicitly called
-out as a specific number of lines from the top of the frame. The
-other values may not matter as much as the panels tend to
-automatically center the image.
-Sync Sense
-The sense of the hsync and vsync pulses may be called out in the data
-sheet. On one panel, the sense of these pulses determine the height
-of the visible region on the panel. Most of the Sharp panels use
-negative sense sync pulses set by the TIM2_IHS and TIM2_IVS bits in
-Pel Layout
-The Sharp color TFT panels are all configured for 16 bit direct color
-modes. The amba-lcd driver sets the pel mode to 565 for 5 bits of
-each red and blue and 6 bits of green.
diff --git a/Documentation/arm/Sharp-LH/LPD7A400 b/Documentation/arm/Sharp-LH/LPD7A400
deleted file mode 100644
index 3275b453bfd..00000000000
--- a/Documentation/arm/Sharp-LH/LPD7A400
+++ /dev/null
@@ -1,15 +0,0 @@
-README on Implementing Linux for the Logic PD LPD7A400-10
-- CPLD memory mapping
- The board designers chose to use high address lines for controlling
- access to the CPLD registers. It turns out to be a big waste
- because we're using an MMU and must map IO space into virtual
- memory. The result is that we have to make a mapping for every
- register.
-- Serial Console
- It may be OK not to use the serial console option if the user passes
- the console device name to the kernel. This deserves some exploration.
diff --git a/Documentation/arm/Sharp-LH/LPD7A40X b/Documentation/arm/Sharp-LH/LPD7A40X
deleted file mode 100644
index 8c29a27e208..00000000000
--- a/Documentation/arm/Sharp-LH/LPD7A40X
+++ /dev/null
@@ -1,16 +0,0 @@
-README on Implementing Linux for the Logic PD LPD7A40X-10
-- CPLD memory mapping
- The board designers chose to use high address lines for controlling
- access to the CPLD registers. It turns out to be a big waste
- because we're using an MMU and must map IO space into virtual
- memory. The result is that we have to make a mapping for every
- register.
-- Serial Console
- It may be OK not to use the serial console option if the user passes
- the console device name to the kernel. This deserves some exploration.
diff --git a/Documentation/arm/Sharp-LH/SDRAM b/Documentation/arm/Sharp-LH/SDRAM
deleted file mode 100644
index 93ddc23c2fa..00000000000
--- a/Documentation/arm/Sharp-LH/SDRAM
+++ /dev/null
@@ -1,51 +0,0 @@
-README on the SDRAM Controller for the LH7a40X
-The standard configuration for the SDRAM controller generates a sparse
-memory array. The precise layout is determined by the SDRAM chips. A
-default kernel configuration assembles the discontiguous memory
-regions into separate memory nodes via the NUMA (Non-Uniform Memory
-Architecture) facilities. In this default configuration, the kernel
-is forgiving about the precise layout. As long as it is given an
-accurate picture of available memory by the bootloader the kernel will
-execute correctly.
-The SDRC supports a mode where some of the chip select lines are
-swapped in order to make SDRAM look like a synchronous ROM. Setting
-this bit means that the RAM will present as a contiguous array. Some
-programmers prefer this to the discontiguous layout. Be aware that
-may be a penalty for this feature where some some configurations of
-memory are significantly reduced; i.e. 64MiB of RAM appears as only 32
-There are a couple of configuration options to override the default
-behavior. When the SROMLL bit is set and memory appears as a
-contiguous array, there is no reason to support NUMA.
-CONFIG_LH7A40X_CONTIGMEM disables NUMA support. When physical memory
-is discontiguous, the memory tables are organized such that there are
-two banks per nodes with a small gap between them. This layout wastes
-some kernel memory for page tables representing non-existent memory.
-CONFIG_LH7A40X_ONE_BANK_PER_NODE optimizes the node tables such that
-there are no gaps. These options control the low level organization
-of the memory management tables in ways that may prevent the kernel
-from booting or may cause the kernel to allocated excessively large
-page tables. Be warned. Only change these options if you know what
-you are doing. The default behavior is a reasonable compromise that
-will suit all users.
-A typical 32MiB system with the default configuration options will
-find physical memory managed as follows.
- node 0: 0xc0000000 4MiB
- 0xc1000000 4MiB
- node 1: 0xc4000000 4MiB
- 0xc5000000 4MiB
- node 2: 0xc8000000 4MiB
- 0xc9000000 4MiB
- node 3: 0xcc000000 4MiB
- 0xcd000000 4MiB
-Setting CONFIG_LH7A40X_ONE_BANK_PER_NODE will put each bank into a
-separate node.
diff --git a/Documentation/arm/Sharp-LH/VectoredInterruptController b/Documentation/arm/Sharp-LH/VectoredInterruptController
deleted file mode 100644
index 23047e9861e..00000000000
--- a/Documentation/arm/Sharp-LH/VectoredInterruptController
+++ /dev/null
@@ -1,80 +0,0 @@
-README on the Vectored Interrupt Controller of the LH7A404
-The 404 revision of the LH7A40X series comes with two vectored
-interrupts controllers. While the kernel does use some of the
-features of these devices, it is far from the purpose for which they
-were designed.
-When this README was written, the implementation of the VICs was in
-flux. It is possible that some details, especially with priorities,
-will change.
-The VIC support code is inspired by routines written by Sharp.
-Priority Control
-The significant reason for using the VIC's vectoring is to control
-interrupt priorities. There are two tables in
-arch/arm/mach-lh7a40x/irq-lh7a404.c that look something like this.
- static unsigned char irq_pri_vic1[] = { IRQ_GPIO3INTR, };
- static unsigned char irq_pri_vic2[] = {
-The initialization code reads these tables and inserts a vector
-address and enable for each indicated IRQ. Vectored interrupts have
-higher priority than non-vectored interrupts. So, on VIC1,
-IRQ_GPIO3INTR will be served before any other non-FIQ interrupt. Due
-to the way that the vectoring works, IRQ_T3UI is the next highest
-priority followed by the other vectored interrupts on VIC2. After
-that, the non-vectored interrupts are scanned in VIC1 then in VIC2.
-The interrupt service routine macro get_irqnr() in
-arch/arm/kernel/entry-armv.S scans the VICs for the next active
-interrupt. The vectoring makes this code somewhat larger than it was
-before using vectoring (refer to the LH7A400 implementation). In the
-case where an interrupt is vectored, the implementation will tend to
-be faster than the non-vectored version. However, the worst-case path
-is longer.
-It is worth noting that at present, there is no need to read
-VIC2_VECTADDR because the register appears to be shared between the
-controllers. The code is written such that if this changes, it ought
-to still work properly.
-Vector Addresses
-The proper use of the vectoring hardware would jump to the ISR
-specified by the vectoring address. Linux isn't structured to take
-advantage of this feature, though it might be possible to change
-things to support it.
-In this implementation, the vectoring address is used to speed the
-search for the active IRQ. The address is coded such that the lowest
-6 bits store the IRQ number for vectored interrupts. These numbers
-correspond to the bits in the interrupt status registers. IRQ zero is
-the lowest interrupt bit in VIC1. IRQ 32 is the lowest interrupt bit
-in VIC2. Because zero is a valid IRQ number and because we cannot
-detect whether or not there is a valid vectoring address if that
-address is zero, the eigth bit (0x100) is set for vectored interrupts.
-The address for IRQ 0x18 (VIC2) is 0x118. Only the ninth bit is set
-for the default handler on VIC1 and only the tenth bit is set for the
-default handler on VIC2.
-In other words.
- 0x000 - no active interrupt
- 0x1ii - vectored interrupt 0xii
- 0x2xx - unvectored interrupt on VIC1 (xx is don't care)
- 0x4xx - unvectored interrupt on VIC2 (xx is don't care)