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authorArnd Bergmann <arnd@arndb.de>2018-03-07 23:21:59 +0300
committerArnd Bergmann <arnd@arndb.de>2018-03-10 01:19:58 +0300
commitfd8773f9f544955f6f47dc2ac3ab85ad64376b7f (patch)
tree2eedaf10b5a4b62df0d3b514cec9614a6af6b563 /Documentation
parent739d875dd6982618020d30f58f8acf10f6076e6d (diff)
downloadlinux-fd8773f9f544955f6f47dc2ac3ab85ad64376b7f.tar.xz
arch: remove frv port
The Fujitsu FRV kernel port has been around for a long time, but has not seen regular updates in several years and instead was marked 'Orphaned' in 2016 by long-time maintainer David Howells. The SoC product line apparently is apparently still around in the form of the Socionext Milbeaut image processor, but this one no longer uses the FRV CPU cores. This removes all FRV specific files from the kernel. Link: http://www.socionext.com/en/products/assp/milbeaut/ Cc: David Howells <dhowells@redhat.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/00-INDEX2
-rw-r--r--Documentation/frv/README.txt51
-rw-r--r--Documentation/frv/atomic-ops.txt134
-rw-r--r--Documentation/frv/booting.txt182
-rw-r--r--Documentation/frv/clock.txt65
-rw-r--r--Documentation/frv/configuring.txt125
-rw-r--r--Documentation/frv/features.txt310
-rw-r--r--Documentation/frv/gdbinit102
-rw-r--r--Documentation/frv/gdbstub.txt130
-rw-r--r--Documentation/frv/kernel-ABI.txt262
-rw-r--r--Documentation/frv/mmu-layout.txt306
11 files changed, 0 insertions, 1669 deletions
diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX
index bd7e2d08d790..b56b88e20196 100644
--- a/Documentation/00-INDEX
+++ b/Documentation/00-INDEX
@@ -172,8 +172,6 @@ fmc/
- information about the FMC bus abstraction
fpga/
- FPGA Manager Core.
-frv/
- - Fujitsu FR-V Linux documentation.
futex-requeue-pi.txt
- info on requeueing of tasks from a non-PI futex to a PI futex
gcc-plugins.txt
diff --git a/Documentation/frv/README.txt b/Documentation/frv/README.txt
deleted file mode 100644
index a984faa968e8..000000000000
--- a/Documentation/frv/README.txt
+++ /dev/null
@@ -1,51 +0,0 @@
- ================================
- Fujitsu FR-V LINUX DOCUMENTATION
- ================================
-
-This directory contains documentation for the Fujitsu FR-V CPU architecture
-port of Linux.
-
-The following documents are available:
-
- (*) features.txt
-
- A description of the basic features inherent in this architecture port.
-
-
- (*) configuring.txt
-
- A summary of the configuration options particular to this architecture.
-
-
- (*) booting.txt
-
- A description of how to boot the kernel image and a summary of the kernel
- command line options.
-
-
- (*) gdbstub.txt
-
- A description of how to debug the kernel using GDB attached by serial
- port, and a summary of the services available.
-
-
- (*) mmu-layout.txt
-
- A description of the virtual and physical memory layout used in the
- MMU linux kernel, and the registers used to support it.
-
-
- (*) gdbinit
-
- An example .gdbinit file for use with GDB. It includes macros for viewing
- MMU state on the FR451. See mmu-layout.txt for more information.
-
-
- (*) clock.txt
-
- A description of the CPU clock scaling interface.
-
-
- (*) atomic-ops.txt
-
- A description of how the FR-V kernel's atomic operations work.
diff --git a/Documentation/frv/atomic-ops.txt b/Documentation/frv/atomic-ops.txt
deleted file mode 100644
index 96638e9b9fe0..000000000000
--- a/Documentation/frv/atomic-ops.txt
+++ /dev/null
@@ -1,134 +0,0 @@
- =====================================
- FUJITSU FR-V KERNEL ATOMIC OPERATIONS
- =====================================
-
-On the FR-V CPUs, there is only one atomic Read-Modify-Write operation: the SWAP/SWAPI
-instruction. Unfortunately, this alone can't be used to implement the following operations:
-
- (*) Atomic add to memory
-
- (*) Atomic subtract from memory
-
- (*) Atomic bit modification (set, clear or invert)
-
- (*) Atomic compare and exchange
-
-On such CPUs, the standard way of emulating such operations in uniprocessor mode is to disable
-interrupts, but on the FR-V CPUs, modifying the PSR takes a lot of clock cycles, and it has to be
-done twice. This means the CPU runs for a relatively long time with interrupts disabled,
-potentially having a great effect on interrupt latency.
-
-
-=============
-NEW ALGORITHM
-=============
-
-To get around this, the following algorithm has been implemented. It operates in a way similar to
-the LL/SC instruction pairs supported on a number of platforms.
-
- (*) The CCCR.CC3 register is reserved within the kernel to act as an atomic modify abort flag.
-
- (*) In the exception prologues run on kernel->kernel entry, CCCR.CC3 is set to 0 (Undefined
- state).
-
- (*) All atomic operations can then be broken down into the following algorithm:
-
- (1) Set ICC3.Z to true and set CC3 to True (ORCC/CKEQ/ORCR).
-
- (2) Load the value currently in the memory to be modified into a register.
-
- (3) Make changes to the value.
-
- (4) If CC3 is still True, simultaneously and atomically (by VLIW packing):
-
- (a) Store the modified value back to memory.
-
- (b) Set ICC3.Z to false (CORCC on GR29 is sufficient for this - GR29 holds the current
- task pointer in the kernel, and so is guaranteed to be non-zero).
-
- (5) If ICC3.Z is still true, go back to step (1).
-
-This works in a non-SMP environment because any interrupt or other exception that happens between
-steps (1) and (4) will set CC3 to the Undefined, thus aborting the store in (4a), and causing the
-condition in ICC3 to remain with the Z flag set, thus causing step (5) to loop back to step (1).
-
-
-This algorithm suffers from two problems:
-
- (1) The condition CCCR.CC3 is cleared unconditionally by an exception, irrespective of whether or
- not any changes were made to the target memory location during that exception.
-
- (2) The branch from step (5) back to step (1) may have to happen more than once until the store
- manages to take place. In theory, this loop could cycle forever because there are too many
- interrupts coming in, but it's unlikely.
-
-
-=======
-EXAMPLE
-=======
-
-Taking an example from include/asm-frv/atomic.h:
-
- static inline int atomic_add_return(int i, atomic_t *v)
- {
- unsigned long val;
-
- asm("0: \n"
-
-It starts by setting ICC3.Z to true for later use, and also transforming that into CC3 being in the
-True state.
-
- " orcc gr0,gr0,gr0,icc3 \n" <-- (1)
- " ckeq icc3,cc7 \n" <-- (1)
-
-Then it does the load. Note that the final phase of step (1) is done at the same time as the
-load. The VLIW packing ensures they are done simultaneously. The ".p" on the load must not be
-removed without swapping the order of these two instructions.
-
- " ld.p %M0,%1 \n" <-- (2)
- " orcr cc7,cc7,cc3 \n" <-- (1)
-
-Then the proposed modification is generated. Note that the old value can be retained if required
-(such as in test_and_set_bit()).
-
- " add%I2 %1,%2,%1 \n" <-- (3)
-
-Then it attempts to store the value back, contingent on no exception having cleared CC3 since it
-was set to True.
-
- " cst.p %1,%M0 ,cc3,#1 \n" <-- (4a)
-
-It simultaneously records the success or failure of the store in ICC3.Z.
-
- " corcc gr29,gr29,gr0 ,cc3,#1 \n" <-- (4b)
-
-Such that the branch can then be taken if the operation was aborted.
-
- " beq icc3,#0,0b \n" <-- (5)
- : "+U"(v->counter), "=&r"(val)
- : "NPr"(i)
- : "memory", "cc7", "cc3", "icc3"
- );
-
- return val;
- }
-
-
-=============
-CONFIGURATION
-=============
-
-The atomic ops implementation can be made inline or out-of-line by changing the
-CONFIG_FRV_OUTOFLINE_ATOMIC_OPS configuration variable. Making it out-of-line has a number of
-advantages:
-
- - The resulting kernel image may be smaller
- - Debugging is easier as atomic ops can just be stepped over and they can be breakpointed
-
-Keeping it inline also has a number of advantages:
-
- - The resulting kernel may be Faster
- - no out-of-line function calls need to be made
- - the compiler doesn't have half its registers clobbered by making a call
-
-The out-of-line implementations live in arch/frv/lib/atomic-ops.S.
diff --git a/Documentation/frv/booting.txt b/Documentation/frv/booting.txt
deleted file mode 100644
index cd9dc1dfb144..000000000000
--- a/Documentation/frv/booting.txt
+++ /dev/null
@@ -1,182 +0,0 @@
- =========================
- BOOTING FR-V LINUX KERNEL
- =========================
-
-======================
-PROVIDING A FILESYSTEM
-======================
-
-First of all, a root filesystem must be made available. This can be done in
-one of two ways:
-
- (1) NFS Export
-
- A filesystem should be constructed in a directory on an NFS server that
- the target board can reach. This directory should then be NFS exported
- such that the target board can read and write into it as root.
-
- (2) Flash Filesystem (JFFS2 Recommended)
-
- In this case, the image must be stored or built up on flash before it
- can be used. A complete image can be built using the mkfs.jffs2 or
- similar program and then downloaded and stored into flash by RedBoot.
-
-
-========================
-LOADING THE KERNEL IMAGE
-========================
-
-The kernel will need to be loaded into RAM by RedBoot (or by some alternative
-boot loader) before it can be run. The kernel image (arch/frv/boot/Image) may
-be loaded in one of three ways:
-
- (1) Load from Flash
-
- This is the simplest. RedBoot can store an image in the flash (see the
- RedBoot documentation) and then load it back into RAM. RedBoot keeps
- track of the load address, entry point and size, so the command to do
- this is simply:
-
- fis load linux
-
- The image is then ready to be executed.
-
- (2) Load by TFTP
-
- The following command will download a raw binary kernel image from the
- default server (as negotiated by BOOTP) and store it into RAM:
-
- load -b 0x00100000 -r /tftpboot/image.bin
-
- The image is then ready to be executed.
-
- (3) Load by Y-Modem
-
- The following command will download a raw binary kernel image across the
- serial port that RedBoot is currently using:
-
- load -m ymodem -b 0x00100000 -r zImage
-
- The serial client (such as minicom) must then be told to transmit the
- program by Y-Modem.
-
- When finished, the image will then be ready to be executed.
-
-
-==================
-BOOTING THE KERNEL
-==================
-
-Boot the image with the following RedBoot command:
-
- exec -c "<CMDLINE>" 0x00100000
-
-For example:
-
- exec -c "console=ttySM0,115200 ip=:::::dhcp root=/dev/mtdblock2 rw"
-
-This will start the kernel running. Note that if the GDB-stub is compiled in,
-then the kernel will immediately wait for GDB to connect over serial before
-doing anything else. See the section on kernel debugging with GDB.
-
-The kernel command line <CMDLINE> tells the kernel where its console is and
-how to find its root filesystem. This is made up of the following components,
-separated by spaces:
-
- (*) console=ttyS<x>[,<baud>[<parity>[<bits>[<flow>]]]]
-
- This specifies that the system console should output through on-chip
- serial port <x> (which can be "0" or "1").
-
- <baud> is a standard baud rate between 1200 and 115200 (default 9600).
-
- <parity> is a parity setting of "N", "O", "E", "M" or "S" for None, Odd,
- Even, Mark or Space. "None" is the default.
-
- <stop> is "7" or "8" for the number of bits per character. "8" is the
- default.
-
- <flow> is "r" to use flow control (XCTS on serial port 2 only). The
- default is to not use flow control.
-
- For example:
-
- console=ttyS0,115200
-
- To use the first on-chip serial port at baud rate 115200, no parity, 8
- bits, and no flow control.
-
- (*) root=<xxxx>
-
- This specifies the device upon which the root filesystem resides. It
- may be specified by major and minor number, device path, or even
- partition uuid, if supported. For example:
-
- /dev/nfs NFS root filesystem
- /dev/mtdblock3 Fourth RedBoot partition on the System Flash
- PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF/PARTNROFF=1
- first partition after the partition with the given UUID
- 253:0 Device with major 253 and minor 0
-
- Authoritative information can be found in
- "Documentation/admin-guide/kernel-parameters.rst".
-
- (*) rw
-
- Start with the root filesystem mounted Read/Write.
-
- The remaining components are all optional:
-
- (*) ip=<ip>::::<host>:<iface>:<cfg>
-
- Configure the network interface. If <cfg> is "off" then <ip> should
- specify the IP address for the network device <iface>. <host> provide
- the hostname for the device.
-
- If <cfg> is "bootp" or "dhcp", then all of these parameters will be
- discovered by consulting a BOOTP or DHCP server.
-
- For example, the following might be used:
-
- ip=192.168.73.12::::frv:eth0:off
-
- This sets the IP address on the VDK motherboard RTL8029 ethernet chipset
- (eth0) to be 192.168.73.12, and sets the board's hostname to be "frv".
-
- (*) nfsroot=<server>:<dir>[,v<vers>]
-
- This is mandatory if "root=/dev/nfs" is given as an option. It tells the
- kernel the IP address of the NFS server providing its root filesystem,
- and the pathname on that server of the filesystem.
-
- The NFS version to use can also be specified. v2 and v3 are supported by
- Linux.
-
- For example:
-
- nfsroot=192.168.73.1:/nfsroot-frv
-
- (*) profile=1
-
- Turns on the kernel profiler (accessible through /proc/profile).
-
- (*) console=gdb0
-
- This can be used as an alternative to the "console=ttyS..." listed
- above. I tells the kernel to pass the console output to GDB if the
- gdbstub is compiled in to the kernel.
-
- If this is used, then the gdbstub passes the text to GDB, which then
- simply dumps it to its standard output.
-
- (*) mem=<xxx>M
-
- Normally the kernel will work out how much SDRAM it has by reading the
- SDRAM controller registers. That can be overridden with this
- option. This allows the kernel to be told that it has <xxx> megabytes of
- memory available.
-
- (*) init=<prog> [<arg> [<arg> [<arg> ...]]]
-
- This tells the kernel what program to run initially. By default this is
- /sbin/init, but /sbin/sash or /bin/sh are common alternatives.
diff --git a/Documentation/frv/clock.txt b/Documentation/frv/clock.txt
deleted file mode 100644
index c72d350e177a..000000000000
--- a/Documentation/frv/clock.txt
+++ /dev/null
@@ -1,65 +0,0 @@
-Clock scaling
--------------
-
-The kernel supports scaling of CLCK.CMODE, CLCK.CM and CLKC.P0 clock
-registers. If built with CONFIG_PM and CONFIG_SYSCTL options enabled, four
-extra files will appear in the directory /proc/sys/pm/. Reading these files
-will show:
-
- p0 -- current value of the P0 bit in CLKC register.
- cm -- current value of the CM bits in CLKC register.
- cmode -- current value of the CMODE bits in CLKC register.
-
-On all boards, the 'p0' file should also be writable, and either '1' or '0'
-can be rewritten, to set or clear the CLKC_P0 bit respectively, hence
-controlling whether the resource bus rate clock is halved.
-
-The 'cm' file should also be available on all boards. '0' can be written to it
-to shift the board into High-Speed mode (normal), and '1' can be written to
-shift the board into Medium-Speed mode. Selecting Low-Speed mode is not
-supported by this interface, even though some CPUs do support it.
-
-On the boards with FR405 CPU (i.e. CB60 and CB70), the 'cmode' file is also
-writable, allowing the CPU core speed (and other clock speeds) to be
-controlled from userspace.
-
-
-Determining current and possible settings
------------------------------------------
-
-The current state and the available masks can be found in /proc/cpuinfo. For
-example, on the CB70:
-
- # cat /proc/cpuinfo
- CPU-Series: fr400
- CPU-Core: fr405, gr0-31, BE, CCCR
- CPU: mb93405
- MMU: Prot
- FP-Media: fr0-31, Media
- System: mb93091-cb70, mb93090-mb00
- PM-Controls: cmode=0xd31f, cm=0x3, p0=0x3, suspend=0x9
- PM-Status: cmode=3, cm=0, p0=0
- Clock-In: 50.00 MHz
- Clock-Core: 300.00 MHz
- Clock-SDRAM: 100.00 MHz
- Clock-CBus: 100.00 MHz
- Clock-Res: 50.00 MHz
- Clock-Ext: 50.00 MHz
- Clock-DSU: 25.00 MHz
- BogoMips: 300.00
-
-And on the PDK, the PM lines look like the following:
-
- PM-Controls: cm=0x3, p0=0x3, suspend=0x9
- PM-Status: cmode=9, cm=0, p0=0
-
-The PM-Controls line, if present, will indicate which /proc/sys/pm files can
-be set to what values. The specification values are bitmasks; so, for example,
-"suspend=0x9" indicates that 0 and 3 can be written validly to
-/proc/sys/pm/suspend.
-
-The PM-Controls line will only be present if CONFIG_PM is configured to Y.
-
-The PM-Status line indicates which clock controls are set to which value. If
-the file can be read, then the suspend value must be 0, and so that's not
-included.
diff --git a/Documentation/frv/configuring.txt b/Documentation/frv/configuring.txt
deleted file mode 100644
index 36e76a2336fa..000000000000
--- a/Documentation/frv/configuring.txt
+++ /dev/null
@@ -1,125 +0,0 @@
- =======================================
- FUJITSU FR-V LINUX KERNEL CONFIGURATION
- =======================================
-
-=====================
-CONFIGURATION OPTIONS
-=====================
-
-The most important setting is in the "MMU support options" tab (the first
-presented in the configuration tools available):
-
- (*) "Kernel Type"
-
- This options allows selection of normal, MMU-requiring linux, and uClinux
- (which doesn't require an MMU and doesn't have inter-process protection).
-
-There are a number of settings in the "Processor type and features" section of
-the kernel configuration that need to be considered.
-
- (*) "CPU"
-
- The register and instruction sets at the core of the processor. This can
- only be set to "FR40x/45x/55x" at the moment - but this permits usage of
- the kernel with MB93091 CB10, CB11, CB30, CB41, CB60, CB70 and CB451
- CPU boards, and with the MB93093 PDK board.
-
- (*) "System"
-
- This option allows a choice of basic system. This governs the peripherals
- that are expected to be available.
-
- (*) "Motherboard"
-
- This specifies the type of motherboard being used, and the peripherals
- upon it. Currently only "MB93090-MB00" can be set here.
-
- (*) "Default cache-write mode"
-
- This controls the initial data cache write management mode. By default
- Write-Through is selected, but Write-Back (Copy-Back) can also be
- selected. This can be changed dynamically once the kernel is running (see
- features.txt).
-
-There are some architecture specific configuration options in the "General
-Setup" section of the kernel configuration too:
-
- (*) "Reserve memory uncached for (PCI) DMA"
-
- This requests that a uClinux kernel set aside some memory in an uncached
- window for the use as consistent DMA memory (mainly for PCI). At least a
- megabyte will be allocated in this way, possibly more. Any memory so
- reserved will not be available for normal allocations.
-
- (*) "Kernel support for ELF-FDPIC binaries"
-
- This enables the binary-format driver for the new FDPIC ELF binaries that
- this platform normally uses. These binaries are totally relocatable -
- their separate sections can relocated independently, allowing them to be
- shared on uClinux where possible. This should normally be enabled.
-
- (*) "Kernel image protection"
-
- This makes the protection register governing access to the core kernel
- image prohibit access by userspace programs. This option is available on
- uClinux only.
-
-There are also a number of settings in the "Kernel Hacking" section of the
-kernel configuration especially for debugging a kernel on this
-architecture. See the "gdbstub.txt" file for information about those.
-
-
-======================
-DEFAULT CONFIGURATIONS
-======================
-
-The kernel sources include a number of example default configurations:
-
- (*) defconfig-mb93091
-
- Default configuration for the MB93091-VDK with both CPU board and
- MB93090-MB00 motherboard running uClinux.
-
-
- (*) defconfig-mb93091-fb
-
- Default configuration for the MB93091-VDK with CPU board,
- MB93090-MB00 motherboard, and DAV board running uClinux.
- Includes framebuffer driver.
-
-
- (*) defconfig-mb93093
-
- Default configuration for the MB93093-PDK board running uClinux.
-
-
- (*) defconfig-cb70-standalone
-
- Default configuration for the MB93091-VDK with only CB70 CPU board
- running uClinux. This will use the CB70's DM9000 for network access.
-
-
- (*) defconfig-mmu
-
- Default configuration for the MB93091-VDK with both CB451 CPU board and
- MB93090-MB00 motherboard running MMU linux.
-
- (*) defconfig-mmu-audio
-
- Default configuration for the MB93091-VDK with CB451 CPU board, DAV
- board, and MB93090-MB00 motherboard running MMU linux. Includes
- audio driver.
-
- (*) defconfig-mmu-fb
-
- Default configuration for the MB93091-VDK with CB451 CPU board, DAV
- board, and MB93090-MB00 motherboard running MMU linux. Includes
- framebuffer driver.
-
- (*) defconfig-mmu-standalone
-
- Default configuration for the MB93091-VDK with only CB451 CPU board
- running MMU linux.
-
-
-
diff --git a/Documentation/frv/features.txt b/Documentation/frv/features.txt
deleted file mode 100644
index fa20c0e72833..000000000000
--- a/Documentation/frv/features.txt
+++ /dev/null
@@ -1,310 +0,0 @@
- ===========================
- FUJITSU FR-V LINUX FEATURES
- ===========================
-
-This kernel port has a number of features of which the user should be aware:
-
- (*) Linux and uClinux
-
- The FR-V architecture port supports both normal MMU linux and uClinux out
- of the same sources.
-
-
- (*) CPU support
-
- Support for the FR401, FR403, FR405, FR451 and FR555 CPUs should work with
- the same uClinux kernel configuration.
-
- In normal (MMU) Linux mode, only the FR451 CPU will work as that is the
- only one with a suitably featured CPU.
-
- The kernel is written and compiled with the assumption that only the
- bottom 32 GR registers and no FR registers will be used by the kernel
- itself, however all extra userspace registers will be saved on context
- switch. Note that since most CPUs can't support lazy switching, no attempt
- is made to do lazy register saving where that would be possible (FR555
- only currently).
-
-
- (*) Board support
-
- The board on which the kernel will run can be configured on the "Processor
- type and features" configuration tab.
-
- Set the System to "MB93093-PDK" to boot from the MB93093 (FR403) PDK.
-
- Set the System to "MB93091-VDK" to boot from the CB11, CB30, CB41, CB60,
- CB70 or CB451 VDK boards. Set the Motherboard setting to "MB93090-MB00" to
- boot with the standard ATA90590B VDK motherboard, and set it to "None" to
- boot without any motherboard.
-
-
- (*) Binary Formats
-
- The only userspace binary format supported is FDPIC ELF. Normal ELF, FLAT
- and AOUT binaries are not supported for this architecture.
-
- FDPIC ELF supports shared library and program interpreter facilities.
-
-
- (*) Scheduler Speed
-
- The kernel scheduler runs at 100Hz irrespective of the clock speed on this
- architecture. This value is set in asm/param.h (see the HZ macro defined
- there).
-
-
- (*) Normal (MMU) Linux Memory Layout.
-
- See mmu-layout.txt in this directory for a description of the normal linux
- memory layout
-
- See include/asm-frv/mem-layout.h for constants pertaining to the memory
- layout.
-
- See include/asm-frv/mb-regs.h for the constants pertaining to the I/O bus
- controller configuration.
-
-
- (*) uClinux Memory Layout
-
- The memory layout used by the uClinux kernel is as follows:
-
- 0x00000000 - 0x00000FFF Null pointer catch page
- 0x20000000 - 0x200FFFFF CS2# [PDK] FPGA
- 0xC0000000 - 0xCFFFFFFF SDRAM
- 0xC0000000 Base of Linux kernel image
- 0xE0000000 - 0xEFFFFFFF CS2# [VDK] SLBUS/PCI window
- 0xF0000000 - 0xF0FFFFFF CS5# MB93493 CSC area (DAV daughter board)
- 0xF1000000 - 0xF1FFFFFF CS7# [CB70/CB451] CPU-card PCMCIA port space
- 0xFC000000 - 0xFC0FFFFF CS1# [VDK] MB86943 config space
- 0xFC100000 - 0xFC1FFFFF CS6# [CB70/CB451] CPU-card DM9000 NIC space
- 0xFC100000 - 0xFC1FFFFF CS6# [PDK] AX88796 NIC space
- 0xFC200000 - 0xFC2FFFFF CS3# MB93493 CSR area (DAV daughter board)
- 0xFD000000 - 0xFDFFFFFF CS4# [CB70/CB451] CPU-card extra flash space
- 0xFE000000 - 0xFEFFFFFF Internal CPU peripherals
- 0xFF000000 - 0xFF1FFFFF CS0# Flash 1
- 0xFF200000 - 0xFF3FFFFF CS0# Flash 2
- 0xFFC00000 - 0xFFC0001F CS0# [VDK] FPGA
-
- The kernel reads the size of the SDRAM from the memory bus controller
- registers by default.
-
- The kernel initialisation code (1) adjusts the SDRAM base addresses to
- move the SDRAM to desired address, (2) moves the kernel image down to the
- bottom of SDRAM, (3) adjusts the bus controller registers to move I/O
- windows, and (4) rearranges the protection registers to protect all of
- this.
-
- The reasons for doing this are: (1) the page at address 0 should be
- inaccessible so that NULL pointer errors can be caught; and (2) the bottom
- three quarters are left unoccupied so that an FR-V CPU with an MMU can use
- it for virtual userspace mappings.
-
- See include/asm-frv/mem-layout.h for constants pertaining to the memory
- layout.
-
- See include/asm-frv/mb-regs.h for the constants pertaining to the I/O bus
- controller configuration.
-
-
- (*) uClinux Memory Protection
-
- A DAMPR register is used to cover the entire region used for I/O
- (0xE0000000 - 0xFFFFFFFF). This permits the kernel to make uncached
- accesses to this region. Userspace is not permitted to access it.
-
- The DAMPR/IAMPR protection registers not in use for any other purpose are
- tiled over the top of the SDRAM such that:
-
- (1) The core kernel image is covered by as small a tile as possible
- granting only the kernel access to the underlying data, whilst
- making sure no SDRAM is actually made unavailable by this approach.
-
- (2) All other tiles are arranged to permit userspace access to the rest
- of the SDRAM.
-
- Barring point (1), there is nothing to protect kernel data against
- userspace damage - but this is uClinux.
-
-
- (*) Exceptions and Fixups
-
- Since the FR40x and FR55x CPUs that do not have full MMUs generate
- imprecise data error exceptions, there are currently no automatic fixup
- services available in uClinux. This includes misaligned memory access
- fixups.
-
- Userspace EFAULT errors can be trapped by issuing a MEMBAR instruction and
- forcing the fault to happen there.
-
- On the FR451, however, data exceptions are mostly precise, and so
- exception fixup handling is implemented as normal.
-
-
- (*) Userspace Breakpoints
-
- The ptrace() system call supports the following userspace debugging
- features:
-
- (1) Hardware assisted single step.
-
- (2) Breakpoint via the FR-V "BREAK" instruction.
-
- (3) Breakpoint via the FR-V "TIRA GR0, #1" instruction.
-
- (4) Syscall entry/exit trap.
-
- Each of the above generates a SIGTRAP.
-
-
- (*) On-Chip Serial Ports
-
- The FR-V on-chip serial ports are made available as ttyS0 and ttyS1. Note
- that if the GDB stub is compiled in, ttyS1 will not actually be available
- as it will be being used for the GDB stub.
-
- These ports can be made by:
-
- mknod /dev/ttyS0 c 4 64
- mknod /dev/ttyS1 c 4 65
-
-
- (*) Maskable Interrupts
-
- Level 15 (Non-maskable) interrupts are dealt with by the GDB stub if
- present, and cause a panic if not. If the GDB stub is present, ttyS1's
- interrupts are rated at level 15.
-
- All other interrupts are distributed over the set of available priorities
- so that no IRQs are shared where possible. The arch interrupt handling
- routines attempt to disentangle the various sources available through the
- CPU's own multiplexor, and those on off-CPU peripherals.
-
-
- (*) Accessing PCI Devices
-
- Where PCI is available, care must be taken when dealing with drivers that
- access PCI devices. PCI devices present their data in little-endian form,
- but the CPU sees it in big-endian form. The macros in asm/io.h try to get
- this right, but may not under all circumstances...
-
-
- (*) Ax88796 Ethernet Driver
-
- The MB93093 PDK board has an Ax88796 ethernet chipset (an NE2000 clone). A
- driver has been written to deal specifically with this. The driver
- provides MII services for the card.
-
- The driver can be configured by running make xconfig, and going to:
-
- (*) Network device support
- - turn on "Network device support"
- (*) Ethernet (10 or 100Mbit)
- - turn on "Ethernet (10 or 100Mbit)"
- - turn on "AX88796 NE2000 compatible chipset"
-
- The driver can be found in:
-
- drivers/net/ax88796.c
- include/asm/ax88796.h
-
-
- (*) WorkRAM Driver
-
- This driver provides a character device that permits access to the WorkRAM
- that can be found on the FR451 CPU. Each page is accessible through a
- separate minor number, thereby permitting each page to have its own
- filesystem permissions set on the device file.
-
- The device files should be:
-
- mknod /dev/frv/workram0 c 240 0
- mknod /dev/frv/workram1 c 240 1
- mknod /dev/frv/workram2 c 240 2
- ...
-
- The driver will not permit the opening of any device file that does not
- correspond to at least a partial page of WorkRAM. So the first device file
- is the only one available on the FR451. If any other CPU is detected, none
- of the devices will be openable.
-
- The devices can be accessed with read, write and llseek, and can also be
- mmapped. If they're mmapped, they will only map at the appropriate
- 0x7e8nnnnn address on linux and at the 0xfe8nnnnn address on uClinux. If
- MAP_FIXED is not specified, the appropriate address will be chosen anyway.
-
- The mappings must be MAP_SHARED not MAP_PRIVATE, and must not be
- PROT_EXEC. They must also start at file offset 0, and must not be longer
- than one page in size.
-
- This driver can be configured by running make xconfig, and going to:
-
- (*) Character devices
- - turn on "Fujitsu FR-V CPU WorkRAM support"
-
-
- (*) Dynamic data cache write mode changing
-
- It is possible to view and to change the data cache's write mode through
- the /proc/sys/frv/cache-mode file while the kernel is running. There are
- two modes available:
-
- NAME MEANING
- ===== ==========================================
- wthru Data cache is in Write-Through mode
- wback Data cache is in Write-Back/Copy-Back mode
-
- To read the cache mode:
-
- # cat /proc/sys/frv/cache-mode
- wthru
-
- To change the cache mode:
-
- # echo wback >/proc/sys/frv/cache-mode
- # cat /proc/sys/frv/cache-mode
- wback
-
-
- (*) MMU Context IDs and Pinning
-
- On MMU Linux the CPU supports the concept of a context ID in its MMU to
- make it more efficient (TLB entries are labelled with a context ID to link
- them to specific tasks).
-
- Normally once a context ID is allocated, it will remain affixed to a task
- or CLONE_VM'd group of tasks for as long as it exists. However, since the
- kernel is capable of supporting more tasks than there are possible ID
- numbers, the kernel will pass context IDs from one task to another if
- there are insufficient available.
-
- The context ID currently in use by a task can be viewed in /proc:
-
- # grep CXNR /proc/1/status
- CXNR: 1
-
- Note that kernel threads do not have a userspace context, and so will not
- show a CXNR entry in that file.
-
- Under some circumstances, however, it is desirable to pin a context ID on
- a process such that the kernel won't pass it on. This can be done by
- writing the process ID of the target process to a special file:
-
- # echo 17 >/proc/sys/frv/pin-cxnr
-
- Reading from the file will then show the context ID pinned.
-
- # cat /proc/sys/frv/pin-cxnr
- 4
-
- The context ID will remain pinned as long as any process is using that
- context, i.e.: when the all the subscribing processes have exited or
- exec'd; or when an unpinning request happens:
-
- # echo 0 >/proc/sys/frv/pin-cxnr
-
- When there isn't a pinned context, the file shows -1:
-
- # cat /proc/sys/frv/pin-cxnr
- -1
diff --git a/Documentation/frv/gdbinit b/Documentation/frv/gdbinit
deleted file mode 100644
index 51517b6f307f..000000000000
--- a/Documentation/frv/gdbinit
+++ /dev/null
@@ -1,102 +0,0 @@
-set remotebreak 1
-
-define _amr
-
-printf "AMRx DAMR IAMR \n"
-printf "==== ===================== =====================\n"
-printf "amr0 : L:%08lx P:%08lx : L:%08lx P:%08lx\n",__debug_mmu.damr[0x0].L,__debug_mmu.damr[0x0].P,__debug_mmu.iamr[0x0].L,__debug_mmu.iamr[0x0].P
-printf "amr1 : L:%08lx P:%08lx : L:%08lx P:%08lx\n",__debug_mmu.damr[0x1].L,__debug_mmu.damr[0x1].P,__debug_mmu.iamr[0x1].L,__debug_mmu.iamr[0x1].P
-printf "amr2 : L:%08lx P:%08lx : L:%08lx P:%08lx\n",__debug_mmu.damr[0x2].L,__debug_mmu.damr[0x2].P,__debug_mmu.iamr[0x2].L,__debug_mmu.iamr[0x2].P
-printf "amr3 : L:%08lx P:%08lx : L:%08lx P:%08lx\n",__debug_mmu.damr[0x3].L,__debug_mmu.damr[0x3].P,__debug_mmu.iamr[0x3].L,__debug_mmu.iamr[0x3].P
-printf "amr4 : L:%08lx P:%08lx : L:%08lx P:%08lx\n",__debug_mmu.damr[0x4].L,__debug_mmu.damr[0x4].P,__debug_mmu.iamr[0x4].L,__debug_mmu.iamr[0x4].P
-printf "amr5 : L:%08lx P:%08lx : L:%08lx P:%08lx\n",__debug_mmu.damr[0x5].L,__debug_mmu.damr[0x5].P,__debug_mmu.iamr[0x5].L,__debug_mmu.iamr[0x5].P
-printf "amr6 : L:%08lx P:%08lx : L:%08lx P:%08lx\n",__debug_mmu.damr[0x6].L,__debug_mmu.damr[0x6].P,__debug_mmu.iamr[0x6].L,__debug_mmu.iamr[0x6].P
-printf "amr7 : L:%08lx P:%08lx : L:%08lx P:%08lx\n",__debug_mmu.damr[0x7].L,__debug_mmu.damr[0x7].P,__debug_mmu.iamr[0x7].L,__debug_mmu.iamr[0x7].P
-
-printf "amr8 : L:%08lx P:%08lx\n",__debug_mmu.damr[0x8].L,__debug_mmu.damr[0x8].P
-printf "amr9 : L:%08lx P:%08lx\n",__debug_mmu.damr[0x9].L,__debug_mmu.damr[0x9].P
-printf "amr10: L:%08lx P:%08lx\n",__debug_mmu.damr[0xa].L,__debug_mmu.damr[0xa].P
-printf "amr11: L:%08lx P:%08lx\n",__debug_mmu.damr[0xb].L,__debug_mmu.damr[0xb].P
-
-end
-
-
-define _tlb
-printf "tlb[0x00]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x0].L,__debug_mmu.tlb[0x0].P,__debug_mmu.tlb[0x40+0x0].L,__debug_mmu.tlb[0x40+0x0].P
-printf "tlb[0x01]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x1].L,__debug_mmu.tlb[0x1].P,__debug_mmu.tlb[0x40+0x1].L,__debug_mmu.tlb[0x40+0x1].P
-printf "tlb[0x02]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x2].L,__debug_mmu.tlb[0x2].P,__debug_mmu.tlb[0x40+0x2].L,__debug_mmu.tlb[0x40+0x2].P
-printf "tlb[0x03]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x3].L,__debug_mmu.tlb[0x3].P,__debug_mmu.tlb[0x40+0x3].L,__debug_mmu.tlb[0x40+0x3].P
-printf "tlb[0x04]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x4].L,__debug_mmu.tlb[0x4].P,__debug_mmu.tlb[0x40+0x4].L,__debug_mmu.tlb[0x40+0x4].P
-printf "tlb[0x05]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x5].L,__debug_mmu.tlb[0x5].P,__debug_mmu.tlb[0x40+0x5].L,__debug_mmu.tlb[0x40+0x5].P
-printf "tlb[0x06]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x6].L,__debug_mmu.tlb[0x6].P,__debug_mmu.tlb[0x40+0x6].L,__debug_mmu.tlb[0x40+0x6].P
-printf "tlb[0x07]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x7].L,__debug_mmu.tlb[0x7].P,__debug_mmu.tlb[0x40+0x7].L,__debug_mmu.tlb[0x40+0x7].P
-printf "tlb[0x08]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x8].L,__debug_mmu.tlb[0x8].P,__debug_mmu.tlb[0x40+0x8].L,__debug_mmu.tlb[0x40+0x8].P
-printf "tlb[0x09]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x9].L,__debug_mmu.tlb[0x9].P,__debug_mmu.tlb[0x40+0x9].L,__debug_mmu.tlb[0x40+0x9].P
-printf "tlb[0x0a]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0xa].L,__debug_mmu.tlb[0xa].P,__debug_mmu.tlb[0x40+0xa].L,__debug_mmu.tlb[0x40+0xa].P
-printf "tlb[0x0b]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0xb].L,__debug_mmu.tlb[0xb].P,__debug_mmu.tlb[0x40+0xb].L,__debug_mmu.tlb[0x40+0xb].P
-printf "tlb[0x0c]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0xc].L,__debug_mmu.tlb[0xc].P,__debug_mmu.tlb[0x40+0xc].L,__debug_mmu.tlb[0x40+0xc].P
-printf "tlb[0x0d]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0xd].L,__debug_mmu.tlb[0xd].P,__debug_mmu.tlb[0x40+0xd].L,__debug_mmu.tlb[0x40+0xd].P
-printf "tlb[0x0e]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0xe].L,__debug_mmu.tlb[0xe].P,__debug_mmu.tlb[0x40+0xe].L,__debug_mmu.tlb[0x40+0xe].P
-printf "tlb[0x0f]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0xf].L,__debug_mmu.tlb[0xf].P,__debug_mmu.tlb[0x40+0xf].L,__debug_mmu.tlb[0x40+0xf].P
-printf "tlb[0x10]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x10].L,__debug_mmu.tlb[0x10].P,__debug_mmu.tlb[0x40+0x10].L,__debug_mmu.tlb[0x40+0x10].P
-printf "tlb[0x11]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x11].L,__debug_mmu.tlb[0x11].P,__debug_mmu.tlb[0x40+0x11].L,__debug_mmu.tlb[0x40+0x11].P
-printf "tlb[0x12]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x12].L,__debug_mmu.tlb[0x12].P,__debug_mmu.tlb[0x40+0x12].L,__debug_mmu.tlb[0x40+0x12].P
-printf "tlb[0x13]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x13].L,__debug_mmu.tlb[0x13].P,__debug_mmu.tlb[0x40+0x13].L,__debug_mmu.tlb[0x40+0x13].P
-printf "tlb[0x14]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x14].L,__debug_mmu.tlb[0x14].P,__debug_mmu.tlb[0x40+0x14].L,__debug_mmu.tlb[0x40+0x14].P
-printf "tlb[0x15]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x15].L,__debug_mmu.tlb[0x15].P,__debug_mmu.tlb[0x40+0x15].L,__debug_mmu.tlb[0x40+0x15].P
-printf "tlb[0x16]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x16].L,__debug_mmu.tlb[0x16].P,__debug_mmu.tlb[0x40+0x16].L,__debug_mmu.tlb[0x40+0x16].P
-printf "tlb[0x17]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x17].L,__debug_mmu.tlb[0x17].P,__debug_mmu.tlb[0x40+0x17].L,__debug_mmu.tlb[0x40+0x17].P
-printf "tlb[0x18]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x18].L,__debug_mmu.tlb[0x18].P,__debug_mmu.tlb[0x40+0x18].L,__debug_mmu.tlb[0x40+0x18].P
-printf "tlb[0x19]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x19].L,__debug_mmu.tlb[0x19].P,__debug_mmu.tlb[0x40+0x19].L,__debug_mmu.tlb[0x40+0x19].P
-printf "tlb[0x1a]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x1a].L,__debug_mmu.tlb[0x1a].P,__debug_mmu.tlb[0x40+0x1a].L,__debug_mmu.tlb[0x40+0x1a].P
-printf "tlb[0x1b]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x1b].L,__debug_mmu.tlb[0x1b].P,__debug_mmu.tlb[0x40+0x1b].L,__debug_mmu.tlb[0x40+0x1b].P
-printf "tlb[0x1c]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x1c].L,__debug_mmu.tlb[0x1c].P,__debug_mmu.tlb[0x40+0x1c].L,__debug_mmu.tlb[0x40+0x1c].P
-printf "tlb[0x1d]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x1d].L,__debug_mmu.tlb[0x1d].P,__debug_mmu.tlb[0x40+0x1d].L,__debug_mmu.tlb[0x40+0x1d].P
-printf "tlb[0x1e]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x1e].L,__debug_mmu.tlb[0x1e].P,__debug_mmu.tlb[0x40+0x1e].L,__debug_mmu.tlb[0x40+0x1e].P
-printf "tlb[0x1f]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x1f].L,__debug_mmu.tlb[0x1f].P,__debug_mmu.tlb[0x40+0x1f].L,__debug_mmu.tlb[0x40+0x1f].P
-printf "tlb[0x20]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x20].L,__debug_mmu.tlb[0x20].P,__debug_mmu.tlb[0x40+0x20].L,__debug_mmu.tlb[0x40+0x20].P
-printf "tlb[0x21]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x21].L,__debug_mmu.tlb[0x21].P,__debug_mmu.tlb[0x40+0x21].L,__debug_mmu.tlb[0x40+0x21].P
-printf "tlb[0x22]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x22].L,__debug_mmu.tlb[0x22].P,__debug_mmu.tlb[0x40+0x22].L,__debug_mmu.tlb[0x40+0x22].P
-printf "tlb[0x23]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x23].L,__debug_mmu.tlb[0x23].P,__debug_mmu.tlb[0x40+0x23].L,__debug_mmu.tlb[0x40+0x23].P
-printf "tlb[0x24]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x24].L,__debug_mmu.tlb[0x24].P,__debug_mmu.tlb[0x40+0x24].L,__debug_mmu.tlb[0x40+0x24].P
-printf "tlb[0x25]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x25].L,__debug_mmu.tlb[0x25].P,__debug_mmu.tlb[0x40+0x25].L,__debug_mmu.tlb[0x40+0x25].P
-printf "tlb[0x26]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x26].L,__debug_mmu.tlb[0x26].P,__debug_mmu.tlb[0x40+0x26].L,__debug_mmu.tlb[0x40+0x26].P
-printf "tlb[0x27]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x27].L,__debug_mmu.tlb[0x27].P,__debug_mmu.tlb[0x40+0x27].L,__debug_mmu.tlb[0x40+0x27].P
-printf "tlb[0x28]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x28].L,__debug_mmu.tlb[0x28].P,__debug_mmu.tlb[0x40+0x28].L,__debug_mmu.tlb[0x40+0x28].P
-printf "tlb[0x29]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x29].L,__debug_mmu.tlb[0x29].P,__debug_mmu.tlb[0x40+0x29].L,__debug_mmu.tlb[0x40+0x29].P
-printf "tlb[0x2a]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x2a].L,__debug_mmu.tlb[0x2a].P,__debug_mmu.tlb[0x40+0x2a].L,__debug_mmu.tlb[0x40+0x2a].P
-printf "tlb[0x2b]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x2b].L,__debug_mmu.tlb[0x2b].P,__debug_mmu.tlb[0x40+0x2b].L,__debug_mmu.tlb[0x40+0x2b].P
-printf "tlb[0x2c]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x2c].L,__debug_mmu.tlb[0x2c].P,__debug_mmu.tlb[0x40+0x2c].L,__debug_mmu.tlb[0x40+0x2c].P
-printf "tlb[0x2d]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x2d].L,__debug_mmu.tlb[0x2d].P,__debug_mmu.tlb[0x40+0x2d].L,__debug_mmu.tlb[0x40+0x2d].P
-printf "tlb[0x2e]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x2e].L,__debug_mmu.tlb[0x2e].P,__debug_mmu.tlb[0x40+0x2e].L,__debug_mmu.tlb[0x40+0x2e].P
-printf "tlb[0x2f]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x2f].L,__debug_mmu.tlb[0x2f].P,__debug_mmu.tlb[0x40+0x2f].L,__debug_mmu.tlb[0x40+0x2f].P
-printf "tlb[0x30]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x30].L,__debug_mmu.tlb[0x30].P,__debug_mmu.tlb[0x40+0x30].L,__debug_mmu.tlb[0x40+0x30].P
-printf "tlb[0x31]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x31].L,__debug_mmu.tlb[0x31].P,__debug_mmu.tlb[0x40+0x31].L,__debug_mmu.tlb[0x40+0x31].P
-printf "tlb[0x32]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x32].L,__debug_mmu.tlb[0x32].P,__debug_mmu.tlb[0x40+0x32].L,__debug_mmu.tlb[0x40+0x32].P
-printf "tlb[0x33]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x33].L,__debug_mmu.tlb[0x33].P,__debug_mmu.tlb[0x40+0x33].L,__debug_mmu.tlb[0x40+0x33].P
-printf "tlb[0x34]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x34].L,__debug_mmu.tlb[0x34].P,__debug_mmu.tlb[0x40+0x34].L,__debug_mmu.tlb[0x40+0x34].P
-printf "tlb[0x35]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x35].L,__debug_mmu.tlb[0x35].P,__debug_mmu.tlb[0x40+0x35].L,__debug_mmu.tlb[0x40+0x35].P
-printf "tlb[0x36]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x36].L,__debug_mmu.tlb[0x36].P,__debug_mmu.tlb[0x40+0x36].L,__debug_mmu.tlb[0x40+0x36].P
-printf "tlb[0x37]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x37].L,__debug_mmu.tlb[0x37].P,__debug_mmu.tlb[0x40+0x37].L,__debug_mmu.tlb[0x40+0x37].P
-printf "tlb[0x38]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x38].L,__debug_mmu.tlb[0x38].P,__debug_mmu.tlb[0x40+0x38].L,__debug_mmu.tlb[0x40+0x38].P
-printf "tlb[0x39]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x39].L,__debug_mmu.tlb[0x39].P,__debug_mmu.tlb[0x40+0x39].L,__debug_mmu.tlb[0x40+0x39].P
-printf "tlb[0x3a]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x3a].L,__debug_mmu.tlb[0x3a].P,__debug_mmu.tlb[0x40+0x3a].L,__debug_mmu.tlb[0x40+0x3a].P
-printf "tlb[0x3b]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x3b].L,__debug_mmu.tlb[0x3b].P,__debug_mmu.tlb[0x40+0x3b].L,__debug_mmu.tlb[0x40+0x3b].P
-printf "tlb[0x3c]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x3c].L,__debug_mmu.tlb[0x3c].P,__debug_mmu.tlb[0x40+0x3c].L,__debug_mmu.tlb[0x40+0x3c].P
-printf "tlb[0x3d]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x3d].L,__debug_mmu.tlb[0x3d].P,__debug_mmu.tlb[0x40+0x3d].L,__debug_mmu.tlb[0x40+0x3d].P
-printf "tlb[0x3e]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x3e].L,__debug_mmu.tlb[0x3e].P,__debug_mmu.tlb[0x40+0x3e].L,__debug_mmu.tlb[0x40+0x3e].P
-printf "tlb[0x3f]: %08lx %08lx %08lx %08lx\n",__debug_mmu.tlb[0x3f].L,__debug_mmu.tlb[0x3f].P,__debug_mmu.tlb[0x40+0x3f].L,__debug_mmu.tlb[0x40+0x3f].P
-end
-
-
-define _pgd
-p (pgd_t[0x40])*(pgd_t*)(__debug_mmu.damr[0x3].L)
-end
-
-define _ptd_i
-p (pte_t[0x1000])*(pte_t*)(__debug_mmu.damr[0x4].L)
-end
-
-define _ptd_d
-p (pte_t[0x1000])*(pte_t*)(__debug_mmu.damr[0x5].L)
-end
diff --git a/Documentation/frv/gdbstub.txt b/Documentation/frv/gdbstub.txt
deleted file mode 100644
index b92bfd902a4e..000000000000
--- a/Documentation/frv/gdbstub.txt
+++ /dev/null
@@ -1,130 +0,0 @@
- ====================
- DEBUGGING FR-V LINUX
- ====================
-
-
-The kernel contains a GDB stub that talks GDB remote protocol across a serial
-port. This permits GDB to single step through the kernel, set breakpoints and
-trap exceptions that happen in kernel space and interrupt execution. It also
-permits the NMI interrupt button or serial port events to jump the kernel into
-the debugger.
-
-On the CPUs that have on-chip UARTs (FR400, FR403, FR405, FR555), the
-GDB stub hijacks a serial port for its own purposes, and makes it
-generate level 15 interrupts (NMI). The kernel proper cannot see the serial
-port in question under these conditions.
-
-On the MB93091-VDK CPU boards, the GDB stub uses UART1, which would otherwise
-be /dev/ttyS1. On the MB93093-PDK, the GDB stub uses UART0. Therefore, on the
-PDK there is no externally accessible serial port and the serial port to
-which the touch screen is attached becomes /dev/ttyS0.
-
-Note that the GDB stub runs entirely within CPU debug mode, and so should not
-incur any exceptions or interrupts whilst it is active. In particular, note
-that the clock will lose time since it is implemented in software.
-
-
-==================
-KERNEL PREPARATION
-==================
-
-Firstly, a debuggable kernel must be built. To do this, unpack the kernel tree
-and copy the configuration that you wish to use to .config. Then reconfigure
-the following things on the "Kernel Hacking" tab:
-
- (*) "Include debugging information"
-
- Set this to "Y". This causes all C and Assembly files to be compiled
- to include debugging information.
-
- (*) "In-kernel GDB stub"
-
- Set this to "Y". This causes the GDB stub to be compiled into the
- kernel.
-
- (*) "Immediate activation"
-
- Set this to "Y" if you want the GDB stub to activate as soon as possible
- and wait for GDB to connect. This allows you to start tracing right from
- the beginning of start_kernel() in init/main.c.
-
- (*) "Console through GDB stub"
-
- Set this to "Y" if you wish to be able to use "console=gdb0" on the
- command line. That tells the kernel to pass system console messages to
- GDB (which then prints them on its standard output). This is useful when
- debugging the serial drivers that'd otherwise be used to pass console
- messages to the outside world.
-
-Then build as usual, download to the board and execute. Note that if
-"Immediate activation" was selected, then the kernel will wait for GDB to
-attach. If not, then the kernel will boot immediately and GDB will have to
-interrupt it or wait for an exception to occur before doing anything with
-the kernel.
-
-
-=========================
-KERNEL DEBUGGING WITH GDB
-=========================
-
-Set the serial port on the computer that's going to run GDB to the appropriate
-baud rate. Assuming the board's debug port is connected to ttyS0/COM1 on the
-computer doing the debugging:
-
- stty -F /dev/ttyS0 115200
-
-Then start GDB in the base of the kernel tree:
-
- frv-uclinux-gdb linux [uClinux]
-
-Or:
-
- frv-uclinux-gdb vmlinux [MMU linux]
-
-When the prompt appears:
-
- GNU gdb frv-031024
- Copyright 2003 Free Software Foundation, Inc.
- GDB is free software, covered by the GNU General Public License, and you are
- welcome to change it and/or distribute copies of it under certain conditions.
- Type "show copying" to see the conditions.
- There is absolutely no warranty for GDB. Type "show warranty" for details.
- This GDB was configured as "--host=i686-pc-linux-gnu --target=frv-uclinux"...
- (gdb)
-
-Attach to the board like this:
-
- (gdb) target remote /dev/ttyS0
- Remote debugging using /dev/ttyS0
- start_kernel () at init/main.c:395
- (gdb)
-
-This should show the appropriate lines from the source too. The kernel can
-then be debugged almost as if it's any other program.
-
-
-===============================
-INTERRUPTING THE RUNNING KERNEL
-===============================
-
-The kernel can be interrupted whilst it is running, causing a jump back to the
-GDB stub and the debugger:
-
- (*) Pressing Ctrl-C in GDB. This will cause GDB to try and interrupt the
- kernel by sending an RS232 BREAK over the serial line to the GDB
- stub. This will (mostly) immediately interrupt the kernel and return it
- to the debugger.
-
- (*) Pressing the NMI button on the board will also cause a jump into the
- debugger.
-
- (*) Setting a software breakpoint. This sets a break instruction at the
- desired location which the GDB stub then traps the exception for.
-
- (*) Setting a hardware breakpoint. The GDB stub is capable of using the IBAR
- and DBAR registers to assist debugging.
-
-Furthermore, the GDB stub will intercept a number of exceptions automatically
-if they are caused by kernel execution. It will also intercept BUG() macro
-invocation.
-
diff --git a/Documentation/frv/kernel-ABI.txt b/Documentation/frv/kernel-ABI.txt
deleted file mode 100644
index aaa1cec86f0b..000000000000
--- a/Documentation/frv/kernel-ABI.txt
+++ /dev/null
@@ -1,262 +0,0 @@
- =================================
- INTERNAL KERNEL ABI FOR FR-V ARCH
- =================================
-
-The internal FRV kernel ABI is not quite the same as the userspace ABI. A
-number of the registers are used for special purposed, and the ABI is not
-consistent between modules vs core, and MMU vs no-MMU.
-
-This partly stems from the fact that FRV CPUs do not have a separate
-supervisor stack pointer, and most of them do not have any scratch
-registers, thus requiring at least one general purpose register to be
-clobbered in such an event. Also, within the kernel core, it is possible to
-simply jump or call directly between functions using a relative offset.
-This cannot be extended to modules for the displacement is likely to be too
-far. Thus in modules the address of a function to call must be calculated
-in a register and then used, requiring two extra instructions.
-
-This document has the following sections:
-
- (*) System call register ABI
- (*) CPU operating modes
- (*) Internal kernel-mode register ABI
- (*) Internal debug-mode register ABI
- (*) Virtual interrupt handling
-
-
-========================
-SYSTEM CALL REGISTER ABI
-========================
-
-When a system call is made, the following registers are effective:
-
- REGISTERS CALL RETURN
- =============== ======================= =======================
- GR7 System call number Preserved
- GR8 Syscall arg #1 Return value
- GR9-GR13 Syscall arg #2-6 Preserved
-
-
-===================
-CPU OPERATING MODES
-===================
-
-The FR-V CPU has three basic operating modes. In order of increasing
-capability:
-
- (1) User mode.
-
- Basic userspace running mode.
-
- (2) Kernel mode.
-
- Normal kernel mode. There are many additional control registers
- available that may be accessed in this mode, in addition to all the
- stuff available to user mode. This has two submodes:
-
- (a) Exceptions enabled (PSR.T == 1).
-
- Exceptions will invoke the appropriate normal kernel mode
- handler. On entry to the handler, the PSR.T bit will be cleared.
-
- (b) Exceptions disabled (PSR.T == 0).
-
- No exceptions or interrupts may happen. Any mandatory exceptions
- will cause the CPU to halt unless the CPU is told to jump into
- debug mode instead.
-
- (3) Debug mode.
-
- No exceptions may happen in this mode. Memory protection and
- management exceptions will be flagged for later consideration, but
- the exception handler won't be invoked. Debugging traps such as
- hardware breakpoints and watchpoints will be ignored. This mode is
- entered only by debugging events obtained from the other two modes.
-
- All kernel mode registers may be accessed, plus a few extra debugging
- specific registers.
-
-
-=================================
-INTERNAL KERNEL-MODE REGISTER ABI
-=================================
-
-There are a number of permanent register assignments that are set up by
-entry.S in the exception prologue. Note that there is a complete set of
-exception prologues for each of user->kernel transition and kernel->kernel
-transition. There are also user->debug and kernel->debug mode transition
-prologues.
-
-
- REGISTER FLAVOUR USE
- =============== ======= ==============================================
- GR1 Supervisor stack pointer
- GR15 Current thread info pointer
- GR16 GP-Rel base register for small data
- GR28 Current exception frame pointer (__frame)
- GR29 Current task pointer (current)
- GR30 Destroyed by kernel mode entry
- GR31 NOMMU Destroyed by debug mode entry
- GR31 MMU Destroyed by TLB miss kernel mode entry
- CCR.ICC2 Virtual interrupt disablement tracking
- CCCR.CC3 Cleared by exception prologue
- (atomic op emulation)
- SCR0 MMU See mmu-layout.txt.
- SCR1 MMU See mmu-layout.txt.
- SCR2 MMU Save for EAR0 (destroyed by icache insns
- in debug mode)
- SCR3 MMU Save for GR31 during debug exceptions
- DAMR/IAMR NOMMU Fixed memory protection layout.
- DAMR/IAMR MMU See mmu-layout.txt.
-
-
-Certain registers are also used or modified across function calls:
-
- REGISTER CALL RETURN
- =============== =============================== ======================
- GR0 Fixed Zero -
- GR2 Function call frame pointer
- GR3 Special Preserved
- GR3-GR7 - Clobbered
- GR8 Function call arg #1 Return value
- (or clobbered)
- GR9 Function call arg #2 Return value MSW
- (or clobbered)
- GR10-GR13 Function call arg #3-#6 Clobbered
- GR14 - Clobbered
- GR15-GR16 Special Preserved
- GR17-GR27 - Preserved
- GR28-GR31 Special Only accessed
- explicitly
- LR Return address after CALL Clobbered
- CCR/CCCR - Mostly Clobbered
-
-
-================================
-INTERNAL DEBUG-MODE REGISTER ABI
-================================
-
-This is the same as the kernel-mode register ABI for functions calls. The
-difference is that in debug-mode there's a different stack and a different
-exception frame. Almost all the global registers from kernel-mode
-(including the stack pointer) may be changed.
-
- REGISTER FLAVOUR USE
- =============== ======= ==============================================
- GR1 Debug stack pointer
- GR16 GP-Rel base register for small data
- GR31 Current debug exception frame pointer
- (__debug_frame)
- SCR3 MMU Saved value of GR31
-
-
-Note that debug mode is able to interfere with the kernel's emulated atomic
-ops, so it must be exceedingly careful not to do any that would interact
-with the main kernel in this regard. Hence the debug mode code (gdbstub) is
-almost completely self-contained. The only external code used is the
-sprintf family of functions.
-
-Furthermore, break.S is so complicated because single-step mode does not
-switch off on entry to an exception. That means unless manually disabled,
-single-stepping will blithely go on stepping into things like interrupts.
-See gdbstub.txt for more information.
-
-
-==========================
-VIRTUAL INTERRUPT HANDLING
-==========================
-
-Because accesses to the PSR is so slow, and to disable interrupts we have
-to access it twice (once to read and once to write), we don't actually
-disable interrupts at all if we don't have to. What we do instead is use
-the ICC2 condition code flags to note virtual disablement, such that if we
-then do take an interrupt, we note the flag, really disable interrupts, set
-another flag and resume execution at the point the interrupt happened.
-Setting condition flags as a side effect of an arithmetic or logical
-instruction is really fast. This use of the ICC2 only occurs within the
-kernel - it does not affect userspace.
-
-The flags we use are:
-
- (*) CCR.ICC2.Z [Zero flag]
-
- Set to virtually disable interrupts, clear when interrupts are
- virtually enabled. Can be modified by logical instructions without
- affecting the Carry flag.
-
- (*) CCR.ICC2.C [Carry flag]
-
- Clear to indicate hardware interrupts are really disabled, set otherwise.
-
-
-What happens is this:
-
- (1) Normal kernel-mode operation.
-
- ICC2.Z is 0, ICC2.C is 1.
-
- (2) An interrupt occurs. The exception prologue examines ICC2.Z and
- determines that nothing needs doing. This is done simply with an
- unlikely BEQ instruction.
-
- (3) The interrupts are disabled (local_irq_disable)
-
- ICC2.Z is set to 1.
-
- (4) If interrupts were then re-enabled (local_irq_enable):
-
- ICC2.Z would be set to 0.
-
- A TIHI #2 instruction (trap #2 if condition HI - Z==0 && C==0) would
- be used to trap if interrupts were now virtually enabled, but
- physically disabled - which they're not, so the trap isn't taken. The
- kernel would then be back to state (1).
-
- (5) An interrupt occurs. The exception prologue examines ICC2.Z and
- determines that the interrupt shouldn't actually have happened. It
- jumps aside, and there disabled interrupts by setting PSR.PIL to 14
- and then it clears ICC2.C.
-
- (6) If interrupts were then saved and disabled again (local_irq_save):
-
- ICC2.Z would be shifted into the save variable and masked off
- (giving a 1).
-
- ICC2.Z would then be set to 1 (thus unchanged), and ICC2.C would be
- unaffected (ie: 0).
-
- (7) If interrupts were then restored from state (6) (local_irq_restore):
-
- ICC2.Z would be set to indicate the result of XOR'ing the saved
- value (ie: 1) with 1, which gives a result of 0 - thus leaving
- ICC2.Z set.
-
- ICC2.C would remain unaffected (ie: 0).
-
- A TIHI #2 instruction would be used to again assay the current state,
- but this would do nothing as Z==1.
-
- (8) If interrupts were then enabled (local_irq_enable):
-
- ICC2.Z would be cleared. ICC2.C would be left unaffected. Both
- flags would now be 0.
-
- A TIHI #2 instruction again issued to assay the current state would
- then trap as both Z==0 [interrupts virtually enabled] and C==0
- [interrupts really disabled] would then be true.
-
- (9) The trap #2 handler would simply enable hardware interrupts
- (set PSR.PIL to 0), set ICC2.C to 1 and return.
-
-(10) Immediately upon returning, the pending interrupt would be taken.
-
-(11) The interrupt handler would take the path of actually processing the
- interrupt (ICC2.Z is clear, BEQ fails as per step (2)).
-
-(12) The interrupt handler would then set ICC2.C to 1 since hardware
- interrupts are definitely enabled - or else the kernel wouldn't be here.
-
-(13) On return from the interrupt handler, things would be back to state (1).
-
-This trap (#2) is only available in kernel mode. In user mode it will
-result in SIGILL.
diff --git a/Documentation/frv/mmu-layout.txt b/Documentation/frv/mmu-layout.txt
deleted file mode 100644
index db10250df6be..000000000000
--- a/Documentation/frv/mmu-layout.txt
+++ /dev/null
@@ -1,306 +0,0 @@
- =================================
- FR451 MMU LINUX MEMORY MANAGEMENT
- =================================
-
-============
-MMU HARDWARE
-============
-
-FR451 MMU Linux puts the MMU into EDAT mode whilst running. This means that it uses both the SAT
-registers and the DAT TLB to perform address translation.
-
-There are 8 IAMLR/IAMPR register pairs and 16 DAMLR/DAMPR register pairs for SAT mode.
-
-In DAT mode, there is also a TLB organised in cache format as 64 lines x 2 ways. Each line spans a
-16KB range of addresses, but can match a larger region.
-
-
-===========================
-MEMORY MANAGEMENT REGISTERS
-===========================
-
-Certain control registers are used by the kernel memory management routines:
-
- REGISTERS USAGE
- ====================== ==================================================
- IAMR0, DAMR0 Kernel image and data mappings
- IAMR1, DAMR1 First-chance TLB lookup mapping
- DAMR2 Page attachment for cache flush by page
- DAMR3 Current PGD mapping
- SCR0, DAMR4 Instruction TLB PGE/PTD cache
- SCR1, DAMR5 Data TLB PGE/PTD cache
- DAMR6-10 kmap_atomic() mappings
- DAMR11 I/O mapping
- CXNR mm_struct context ID
- TTBR Page directory (PGD) pointer (physical address)
-
-
-=====================
-GENERAL MEMORY LAYOUT
-=====================
-
-The physical memory layout is as follows:
-
- PHYSICAL ADDRESS CONTROLLER DEVICE
- =================== ============== =======================================
- 00000000 - BFFFFFFF SDRAM SDRAM area
- E0000000 - EFFFFFFF L-BUS CS2# VDK SLBUS/PCI window
- F0000000 - F0FFFFFF L-BUS CS5# MB93493 CSC area (DAV daughter board)
- F1000000 - F1FFFFFF L-BUS CS7# (CB70 CPU-card PCMCIA port I/O space)
- FC000000 - FC0FFFFF L-BUS CS1# VDK MB86943 config space
- FC100000 - FC1FFFFF L-BUS CS6# DM9000 NIC I/O space
- FC200000 - FC2FFFFF L-BUS CS3# MB93493 CSR area (DAV daughter board)
- FD000000 - FDFFFFFF L-BUS CS4# (CB70 CPU-card extra flash space)
- FE000000 - FEFFFFFF Internal CPU peripherals
- FF000000 - FF1FFFFF L-BUS CS0# Flash 1
- FF200000 - FF3FFFFF L-BUS CS0# Flash 2
- FFC00000 - FFC0001F L-BUS CS0# FPGA
-
-The virtual memory layout is:
-
- VIRTUAL ADDRESS PHYSICAL TRANSLATOR FLAGS SIZE OCCUPATION
- ================= ======== ============== ======= ======= ===================================
- 00004000-BFFFFFFF various TLB,xAMR1 D-N-??V 3GB Userspace
- C0000000-CFFFFFFF 00000000 xAMPR0 -L-S--V 256MB Kernel image and data
- D0000000-D7FFFFFF various TLB,xAMR1 D-NS??V 128MB vmalloc area
- D8000000-DBFFFFFF various TLB,xAMR1 D-NS??V 64MB kmap() area
- DC000000-DCFFFFFF various TLB 1MB Secondary kmap_atomic() frame
- DD000000-DD27FFFF various DAMR 160KB Primary kmap_atomic() frame
- DD040000 DAMR2/IAMR2 -L-S--V page Page cache flush attachment point
- DD080000 DAMR3 -L-SC-V page Page Directory (PGD)
- DD0C0000 DAMR4 -L-SC-V page Cached insn TLB Page Table lookup
- DD100000 DAMR5 -L-SC-V page Cached data TLB Page Table lookup
- DD140000 DAMR6 -L-S--V page kmap_atomic(KM_BOUNCE_READ)
- DD180000 DAMR7 -L-S--V page kmap_atomic(KM_SKB_SUNRPC_DATA)
- DD1C0000 DAMR8 -L-S--V page kmap_atomic(KM_SKB_DATA_SOFTIRQ)
- DD200000 DAMR9 -L-S--V page kmap_atomic(KM_USER0)
- DD240000 DAMR10 -L-S--V page kmap_atomic(KM_USER1)
- E0000000-FFFFFFFF E0000000 DAMR11 -L-SC-V 512MB I/O region
-
-IAMPR1 and DAMPR1 are used as an extension to the TLB.
-
-
-====================
-KMAP AND KMAP_ATOMIC
-====================
-
-To access pages in the page cache (which may not be directly accessible if highmem is available),
-the kernel calls kmap(), does the access and then calls kunmap(); or it calls kmap_atomic(), does
-the access and then calls kunmap_atomic().
-
-kmap() creates an attachment between an arbitrary inaccessible page and a range of virtual
-addresses by installing a PTE in a special page table. The kernel can then access this page as it
-wills. When it's finished, the kernel calls kunmap() to clear the PTE.
-
-kmap_atomic() does something slightly different. In the interests of speed, it chooses one of two
-strategies:
-
- (1) If possible, kmap_atomic() attaches the requested page to one of DAMPR5 through DAMPR10
- register pairs; and the matching kunmap_atomic() clears the DAMPR. This makes high memory
- support really fast as there's no need to flush the TLB or modify the page tables. The DAMLR
- registers being used for this are preset during boot and don't change over the lifetime of the
- process. There's a direct mapping between the first few kmap_atomic() types, DAMR number and
- virtual address slot.
-
- However, there are more kmap_atomic() types defined than there are DAMR registers available,
- so we fall back to:
-
- (2) kmap_atomic() uses a slot in the secondary frame (determined by the type parameter), and then
- locks an entry in the TLB to translate that slot to the specified page. The number of slots is
- obviously limited, and their positions are controlled such that each slot is matched by a
- different line in the TLB. kunmap() ejects the entry from the TLB.
-
-Note that the first three kmap atomic types are really just declared as placeholders. The DAMPR
-registers involved are actually modified directly.
-
-Also note that kmap() itself may sleep, kmap_atomic() may never sleep and both always succeed;
-furthermore, a driver using kmap() may sleep before calling kunmap(), but may not sleep before
-calling kunmap_atomic() if it had previously called kmap_atomic().
-
-
-===============================
-USING MORE THAN 256MB OF MEMORY
-===============================
-
-The kernel cannot access more than 256MB of memory directly. The physical layout, however, permits
-up to 3GB of SDRAM (possibly 3.25GB) to be made available. By using CONFIG_HIGHMEM, the kernel can
-allow userspace (by way of page tables) and itself (by way of kmap) to deal with the memory
-allocation.
-
-External devices can, of course, still DMA to and from all of the SDRAM, even if the kernel can't
-see it directly. The kernel translates page references into real addresses for communicating to the
-devices.
-
-
-===================
-PAGE TABLE TOPOLOGY
-===================
-
-The page tables are arranged in 2-layer format. There is a middle layer (PMD) that would be used in
-3-layer format tables but that is folded into the top layer (PGD) and so consumes no extra memory
-or processing power.
-
- +------+ PGD PMD
- | TTBR |--->+-------------------+
- +------+ | | : STE |
- | PGE0 | PME0 : STE |
- | | : STE |
- +-------------------+ Page Table
- | | : STE -------------->+--------+ +0x0000
- | PGE1 | PME0 : STE -----------+ | PTE0 |
- | | : STE -------+ | +--------+
- +-------------------+ | | | PTE63 |
- | | : STE | | +-->+--------+ +0x0100
- | PGE2 | PME0 : STE | | | PTE64 |
- | | : STE | | +--------+
- +-------------------+ | | PTE127 |
- | | : STE | +------>+--------+ +0x0200
- | PGE3 | PME0 : STE | | PTE128 |
- | | : STE | +--------+
- +-------------------+ | PTE191 |
- +--------+ +0x0300
-
-Each Page Directory (PGD) is 16KB (page size) in size and is divided into 64 entries (PGEs). Each
-PGE contains one Page Mid Directory (PMD).
-
-Each PMD is 256 bytes in size and contains a single entry (PME). Each PME holds 64 FR451 MMU
-segment table entries of 4 bytes apiece. Each PME "points to" a page table. In practice, each STE
-points to a subset of the page table, the first to PT+0x0000, the second to PT+0x0100, the third to
-PT+0x200, and so on.
-
-Each PGE and PME covers 64MB of the total virtual address space.
-
-Each Page Table (PTD) is 16KB (page size) in size, and is divided into 4096 entries (PTEs). Each
-entry can point to one 16KB page. In practice, each Linux page table is subdivided into 64 FR451
-MMU page tables. But they are all grouped together to make management easier, in particular rmap
-support is then trivial.
-
-Grouping page tables in this fashion makes PGE caching in SCR0/SCR1 more efficient because the
-coverage of the cached item is greater.
-
-Page tables for the vmalloc area are allocated at boot time and shared between all mm_structs.
-
-
-=================
-USER SPACE LAYOUT
-=================
-
-For MMU capable Linux, the regions userspace code are allowed to access are kept entirely separate
-from those dedicated to the kernel:
-
- VIRTUAL ADDRESS SIZE PURPOSE
- ================= ===== ===================================
- 00000000-00003fff 4KB NULL pointer access trap
- 00004000-01ffffff ~32MB lower mmap space (grows up)
- 02000000-021fffff 2MB Stack space (grows down from top)
- 02200000-nnnnnnnn Executable mapping
- nnnnnnnn- brk space (grows up)
- -bfffffff upper mmap space (grows down)
-
-This is so arranged so as to make best use of the 16KB page tables and the way in which PGEs/PMEs
-are cached by the TLB handler. The lower mmap space is filled first, and then the upper mmap space
-is filled.
-
-
-===============================
-GDB-STUB MMU DEBUGGING SERVICES
-===============================
-
-The gdb-stub included in this kernel provides a number of services to aid in the debugging of MMU
-related kernel services:
-
- (*) Every time the kernel stops, certain state information is dumped into __debug_mmu. This
- variable is defined in arch/frv/kernel/gdb-stub.c. Note that the gdbinit file in this
- directory has some useful macros for dealing with this.
-
- (*) __debug_mmu.tlb[]
-
- This receives the current TLB contents. This can be viewed with the _tlb GDB macro:
-
- (gdb) _tlb
- tlb[0x00]: 01000005 00718203 01000002 00718203
- tlb[0x01]: 01004002 006d4201 01004005 006d4203
- tlb[0x02]: 01008002 006d0201 01008006 00004200
- tlb[0x03]: 0100c006 007f4202 0100c002 0064c202
- tlb[0x04]: 01110005 00774201 01110002 00774201
- tlb[0x05]: 01114005 00770201 01114002 00770201
- tlb[0x06]: 01118002 0076c201 01118005 0076c201
- ...
- tlb[0x3d]: 010f4002 00790200 001f4002 0054ca02
- tlb[0x3e]: 010f8005 0078c201 010f8002 0078c201
- tlb[0x3f]: 001fc002 0056ca01 001fc005 00538a01
-
- (*) __debug_mmu.iamr[]
- (*) __debug_mmu.damr[]
-
- These receive the current IAMR and DAMR contents. These can be viewed with the _amr
- GDB macro:
-
- (gdb) _amr
- AMRx DAMR IAMR
- ==== ===================== =====================
- amr0 : L:c0000000 P:00000cb9 : L:c0000000 P:000004b9
- amr1 : L:01070005 P:006f9203 : L:0102c005 P:006a1201
- amr2 : L:d8d00000 P:00000000 : L:d8d00000 P:00000000
- amr3 : L:d8d04000 P:00534c0d : L:00000000 P:00000000
- amr4 : L:d8d08000 P:00554c0d : L:00000000 P:00000000
- amr5 : L:d8d0c000 P:00554c0d : L:00000000 P:00000000
- amr6 : L:d8d10000 P:00000000 : L:00000000 P:00000000
- amr7 : L:d8d14000 P:00000000 : L:00000000 P:00000000
- amr8 : L:d8d18000 P:00000000
- amr9 : L:d8d1c000 P:00000000
- amr10: L:d8d20000 P:00000000
- amr11: L:e0000000 P:e0000ccd
-
- (*) The current task's page directory is bound to DAMR3.
-
- This can be viewed with the _pgd GDB macro:
-
- (gdb) _pgd
- $3 = {{pge = {{ste = {0x554001, 0x554101, 0x554201, 0x554301, 0x554401,
- 0x554501, 0x554601, 0x554701, 0x554801, 0x554901, 0x554a01,
- 0x554b01, 0x554c01, 0x554d01, 0x554e01, 0x554f01, 0x555001,
- 0x555101, 0x555201, 0x555301, 0x555401, 0x555501, 0x555601,
- 0x555701, 0x555801, 0x555901, 0x555a01, 0x555b01, 0x555c01,
- 0x555d01, 0x555e01, 0x555f01, 0x556001, 0x556101, 0x556201,
- 0x556301, 0x556401, 0x556501, 0x556601, 0x556701, 0x556801,
- 0x556901, 0x556a01, 0x556b01, 0x556c01, 0x556d01, 0x556e01,
- 0x556f01, 0x557001, 0x557101, 0x557201, 0x557301, 0x557401,
- 0x557501, 0x557601, 0x557701, 0x557801, 0x557901, 0x557a01,
- 0x557b01, 0x557c01, 0x557d01, 0x557e01, 0x557f01}}}}, {pge = {{
- ste = {0x0 <repeats 64 times>}}}} <repeats 51 times>, {pge = {{ste = {
- 0x248001, 0x248101, 0x248201, 0x248301, 0x248401, 0x248501,
- 0x248601, 0x248701, 0x248801, 0x248901, 0x248a01, 0x248b01,
- 0x248c01, 0x248d01, 0x248e01, 0x248f01, 0x249001, 0x249101,
- 0x249201, 0x249301, 0x249401, 0x249501, 0x249601, 0x249701,
- 0x249801, 0x249901, 0x249a01, 0x249b01, 0x249c01, 0x249d01,
- 0x249e01, 0x249f01, 0x24a001, 0x24a101, 0x24a201, 0x24a301,
- 0x24a401, 0x24a501, 0x24a601, 0x24a701, 0x24a801, 0x24a901,
- 0x24aa01, 0x24ab01, 0x24ac01, 0x24ad01, 0x24ae01, 0x24af01,
- 0x24b001, 0x24b101, 0x24b201, 0x24b301, 0x24b401, 0x24b501,
- 0x24b601, 0x24b701, 0x24b801, 0x24b901, 0x24ba01, 0x24bb01,
- 0x24bc01, 0x24bd01, 0x24be01, 0x24bf01}}}}, {pge = {{ste = {
- 0x0 <repeats 64 times>}}}} <repeats 11 times>}
-
- (*) The PTD last used by the instruction TLB miss handler is attached to DAMR4.
- (*) The PTD last used by the data TLB miss handler is attached to DAMR5.
-
- These can be viewed with the _ptd_i and _ptd_d GDB macros:
-
- (gdb) _ptd_d
- $5 = {{pte = 0x0} <repeats 127 times>, {pte = 0x539b01}, {
- pte = 0x0} <repeats 896 times>, {pte = 0x719303}, {pte = 0x6d5303}, {
- pte = 0x0}, {pte = 0x0}, {pte = 0x0}, {pte = 0x0}, {pte = 0x0}, {
- pte = 0x0}, {pte = 0x0}, {pte = 0x0}, {pte = 0x0}, {pte = 0x6a1303}, {
- pte = 0x0} <repeats 12 times>, {pte = 0x709303}, {pte = 0x0}, {pte = 0x0},
- {pte = 0x6fd303}, {pte = 0x6f9303}, {pte = 0x6f5303}, {pte = 0x0}, {
- pte = 0x6ed303}, {pte = 0x531b01}, {pte = 0x50db01}, {
- pte = 0x0} <repeats 13 times>, {pte = 0x5303}, {pte = 0x7f5303}, {
- pte = 0x509b01}, {pte = 0x505b01}, {pte = 0x7c9303}, {pte = 0x7b9303}, {
- pte = 0x7b5303}, {pte = 0x7b1303}, {pte = 0x7ad303}, {pte = 0x0}, {
- pte = 0x0}, {pte = 0x7a1303}, {pte = 0x0}, {pte = 0x795303}, {pte = 0x0}, {
- pte = 0x78d303}, {pte = 0x0}, {pte = 0x0}, {pte = 0x0}, {pte = 0x0}, {
- pte = 0x0}, {pte = 0x775303}, {pte = 0x771303}, {pte = 0x76d303}, {
- pte = 0x0}, {pte = 0x765303}, {pte = 0x7c5303}, {pte = 0x501b01}, {
- pte = 0x4f1b01}, {pte = 0x4edb01}, {pte = 0x0}, {pte = 0x4f9b01}, {
- pte = 0x4fdb01}, {pte = 0x0} <repeats 2992 times>}