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-rw-r--r--Documentation/arm/Sharp-LH/ADC-LH7-Touchscreen61
-rw-r--r--Documentation/arm/Sharp-LH/CompactFlash32
-rw-r--r--Documentation/arm/Sharp-LH/IOBarrier45
-rw-r--r--Documentation/arm/Sharp-LH/KEV7A4008
-rw-r--r--Documentation/arm/Sharp-LH/LCDPanels59
-rw-r--r--Documentation/arm/Sharp-LH/LPD7A40015
-rw-r--r--Documentation/arm/Sharp-LH/LPD7A40X16
-rw-r--r--Documentation/arm/Sharp-LH/SDRAM51
-rw-r--r--Documentation/arm/Sharp-LH/VectoredInterruptController80
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 dc460f0..0000000
--- 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
-directory
-
- /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
-samples.
-
- # 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 8616d87..0000000
--- 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 2e953e2..0000000
--- 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
-interfacing.
-
-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
-operation.
-
- SMC IO
- BARRIER IO
-
-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 be32b14..0000000
--- 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 fb1b21c..0000000
--- 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.
-
-
-lcd-panels.h
-------------
-
-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.
-
-
-PIXEL_CLOCK
------------
-
-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.
-
-
-MARGINS
--------
-
-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
-'.tim2'.
-
-
-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 3275b45..0000000
--- 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 8c29a27..0000000
--- 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 93ddc23..0000000
--- 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
-MiB.
-
-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 23047e9..0000000
--- 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[] = {
- IRQ_T3UI, IRQ_GPIO7INTR,
- IRQ_UART1INTR, IRQ_UART2INTR, IRQ_UART3INTR, };
-
-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.
-
-
-ISR
----
-
-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)
-
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