diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/DocBook/Makefile | 2 | ||||
| -rw-r--r-- | Documentation/DocBook/kernel-api.tmpl | 1 | ||||
| -rw-r--r-- | Documentation/acpi-hotkey.txt | 2 | ||||
| -rw-r--r-- | Documentation/fujitsu/frv/kernel-ABI.txt | 192 | ||||
| -rw-r--r-- | Documentation/kernel-parameters.txt | 34 | ||||
| -rw-r--r-- | Documentation/networking/packet_mmap.txt | 2 | ||||
| -rw-r--r-- | Documentation/networking/tuntap.txt | 2 |
7 files changed, 128 insertions, 107 deletions
diff --git a/Documentation/DocBook/Makefile b/Documentation/DocBook/Makefile index 7d87dd73cbe..5a2882d275b 100644 --- a/Documentation/DocBook/Makefile +++ b/Documentation/DocBook/Makefile @@ -2,7 +2,7 @@ # This makefile is used to generate the kernel documentation, # primarily based on in-line comments in various source files. # See Documentation/kernel-doc-nano-HOWTO.txt for instruction in how -# to ducument the SRC - and how to read it. +# to document the SRC - and how to read it. # To add a new book the only step required is to add the book to the # list of DOCBOOKS. diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl index 8c9c6704e85..ca02e04a906 100644 --- a/Documentation/DocBook/kernel-api.tmpl +++ b/Documentation/DocBook/kernel-api.tmpl @@ -322,7 +322,6 @@ X!Earch/i386/kernel/mca.c <chapter id="sysfs"> <title>The Filesystem for Exporting Kernel Objects</title> !Efs/sysfs/file.c -!Efs/sysfs/dir.c !Efs/sysfs/symlink.c !Efs/sysfs/bin.c </chapter> diff --git a/Documentation/acpi-hotkey.txt b/Documentation/acpi-hotkey.txt index 744f1aec655..38040fa3764 100644 --- a/Documentation/acpi-hotkey.txt +++ b/Documentation/acpi-hotkey.txt @@ -30,7 +30,7 @@ specific hotkey(event)) echo "event_num:event_type:event_argument" > /proc/acpi/hotkey/action. The result of the execution of this aml method is -attached to /proc/acpi/hotkey/poll_method, which is dnyamically +attached to /proc/acpi/hotkey/poll_method, which is dynamically created. Please use command "cat /proc/acpi/hotkey/polling_method" to retrieve it. diff --git a/Documentation/fujitsu/frv/kernel-ABI.txt b/Documentation/fujitsu/frv/kernel-ABI.txt index 0ed9b0a779b..8b0a5fc8bfd 100644 --- a/Documentation/fujitsu/frv/kernel-ABI.txt +++ b/Documentation/fujitsu/frv/kernel-ABI.txt @@ -1,17 +1,19 @@ - ================================= - 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. + ================================= + 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: @@ -39,7 +41,8 @@ When a system call is made, the following registers are effective: CPU OPERATING MODES =================== -The FR-V CPU has three basic operating modes. In order of increasing capability: +The FR-V CPU has three basic operating modes. In order of increasing +capability: (1) User mode. @@ -47,42 +50,46 @@ The FR-V CPU has three basic operating modes. In order of increasing capability: (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: + 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. + 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. + 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. + 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. + 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. +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 @@ -92,10 +99,12 @@ transition prologues. 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) + 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) + 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. @@ -104,18 +113,21 @@ transition prologues. 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) + 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 + GR28-GR31 Special Only accessed + explicitly LR Return address after CALL Clobbered CCR/CCCR - Mostly Clobbered @@ -124,46 +136,53 @@ Certain registers are also used or modified across function calls: 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. +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) + 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. +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. -Futhermore, 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. +Futhermore, 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 +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. + 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] @@ -176,8 +195,9 @@ What happens is this: 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. + (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) @@ -187,48 +207,56 @@ What happens is this: 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). + 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. + (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 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). + 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.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. + 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. + 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. + 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. + (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)). +(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. +(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. +This trap (#2) is only available in kernel mode. In user mode it will +result in SIGILL. diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index f8cb55c30b0..b3a6187e530 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1,4 +1,4 @@ -February 2003 Kernel Parameters v2.5.59 + Kernel Parameters ~~~~~~~~~~~~~~~~~ The following is a consolidated list of the kernel parameters as implemented @@ -17,9 +17,17 @@ are specified on the kernel command line with the module name plus usbcore.blinkenlights=1 -The text in square brackets at the beginning of the description states the -restrictions on the kernel for the said kernel parameter to be valid. The -restrictions referred to are that the relevant option is valid if: +This document may not be entirely up to date and comprehensive. The command +"modinfo -p ${modulename}" shows a current list of all parameters of a loadable +module. Loadable modules, after being loaded into the running kernel, also +reveal their parameters in /sys/module/${modulename}/parameters/. Some of these +parameters may be changed at runtime by the command +"echo -n ${value} > /sys/module/${modulename}/parameters/${parm}". + +The parameters listed below are only valid if certain kernel build options were +enabled and if respective hardware is present. The text in square brackets at +the beginning of each description states the restrictions within which a +parameter is applicable: ACPI ACPI support is enabled. ALSA ALSA sound support is enabled. @@ -1046,10 +1054,10 @@ running once the system is up. noltlbs [PPC] Do not use large page/tlb entries for kernel lowmem mapping on PPC40x. - nomce [IA-32] Machine Check Exception - nomca [IA-64] Disable machine check abort handling + nomce [IA-32] Machine Check Exception + noresidual [PPC] Don't use residual data on PReP machines. noresume [SWSUSP] Disables resume and restores original swap @@ -1682,20 +1690,6 @@ running once the system is up. ______________________________________________________________________ -Changelog: - -2000-06-?? Mr. Unknown - The last known update (for 2.4.0) - the changelog was not kept before. - -2002-11-24 Petr Baudis <pasky@ucw.cz> - Randy Dunlap <randy.dunlap@verizon.net> - Update for 2.5.49, description for most of the options introduced, - references to other documentation (C files, READMEs, ..), added S390, - PPC, SPARC, MTD, ALSA and OSS category. Minor corrections and - reformatting. - -2005-10-19 Randy Dunlap <rdunlap@xenotime.net> - Lots of typos, whitespace, some reformatting. TODO: diff --git a/Documentation/networking/packet_mmap.txt b/Documentation/networking/packet_mmap.txt index 4fc8e987432..aaf99d5f0da 100644 --- a/Documentation/networking/packet_mmap.txt +++ b/Documentation/networking/packet_mmap.txt @@ -254,7 +254,7 @@ and, the number of frames be <block number> * <block size> / <frame size> -Suposse the following parameters, which apply for 2.6 kernel and an +Suppose the following parameters, which apply for 2.6 kernel and an i386 architecture: <size-max> = 131072 bytes diff --git a/Documentation/networking/tuntap.txt b/Documentation/networking/tuntap.txt index ec3d109d787..76750fb9151 100644 --- a/Documentation/networking/tuntap.txt +++ b/Documentation/networking/tuntap.txt @@ -138,7 +138,7 @@ This means that you have to read/write IP packets when you are using tun and ethernet frames when using tap. 5. What is the difference between BPF and TUN/TAP driver? -BFP is an advanced packet filter. It can be attached to existing +BPF is an advanced packet filter. It can be attached to existing network interface. It does not provide a virtual network interface. A TUN/TAP driver does provide a virtual network interface and it is possible to attach BPF to this interface. |