diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/acpi-hotkey.txt | 3 | ||||
| -rw-r--r-- | Documentation/arm/Samsung-S3C24XX/USB-Host.txt | 93 | ||||
| -rw-r--r-- | Documentation/feature-removal-schedule.txt | 12 | ||||
| -rw-r--r-- | Documentation/kernel-parameters.txt | 5 | ||||
| -rw-r--r-- | Documentation/kprobes.txt | 588 | ||||
| -rw-r--r-- | Documentation/networking/cxgb.txt | 352 | ||||
| -rw-r--r-- | Documentation/networking/phy.txt | 288 | ||||
| -rw-r--r-- | Documentation/pci.txt | 14 | ||||
| -rw-r--r-- | Documentation/serial/driver | 15 | ||||
| -rw-r--r-- | Documentation/sound/alsa/ALSA-Configuration.txt | 1 | ||||
| -rw-r--r-- | Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl | 15 | ||||
| -rw-r--r-- | Documentation/usb/usbmon.txt | 2 | ||||
| -rw-r--r-- | Documentation/video4linux/bttv/Insmod-options | 3 | ||||
| -rw-r--r-- | Documentation/x86_64/boot-options.txt | 5 |
14 files changed, 1366 insertions, 30 deletions
diff --git a/Documentation/acpi-hotkey.txt b/Documentation/acpi-hotkey.txt index 4c115a7bb82..0acdc80c30c 100644 --- a/Documentation/acpi-hotkey.txt +++ b/Documentation/acpi-hotkey.txt @@ -33,3 +33,6 @@ The result of the execution of this aml method is attached to /proc/acpi/hotkey/poll_method, which is dnyamically created. Please use command "cat /proc/acpi/hotkey/polling_method" to retrieve it. + +Note: Use cmdline "acpi_generic_hotkey" to over-ride +loading any platform specific drivers. diff --git a/Documentation/arm/Samsung-S3C24XX/USB-Host.txt b/Documentation/arm/Samsung-S3C24XX/USB-Host.txt new file mode 100644 index 00000000000..b93b68e2b14 --- /dev/null +++ b/Documentation/arm/Samsung-S3C24XX/USB-Host.txt @@ -0,0 +1,93 @@ + S3C24XX USB Host support + ======================== + + + +Introduction +------------ + + This document details the S3C2410/S3C2440 in-built OHCI USB host support. + +Configuration +------------- + + Enable at least the following kernel options: + + menuconfig: + + Device Drivers ---> + USB support ---> + <*> Support for Host-side USB + <*> OHCI HCD support + + + .config: + CONFIG_USB + CONFIG_USB_OHCI_HCD + + + Once these options are configured, the standard set of USB device + drivers can be configured and used. + + +Board Support +------------- + + The driver attaches to a platform device, which will need to be + added by the board specific support file in linux/arch/arm/mach-s3c2410, + such as mach-bast.c or mach-smdk2410.c + + The platform device's platform_data field is only needed if the + board implements extra power control or over-current monitoring. + + The OHCI driver does not ensure the state of the S3C2410's MISCCTRL + register, so if both ports are to be used for the host, then it is + the board support file's responsibility to ensure that the second + port is configured to be connected to the OHCI core. + + +Platform Data +------------- + + See linux/include/asm-arm/arch-s3c2410/usb-control.h for the + descriptions of the platform device data. An implementation + can be found in linux/arch/arm/mach-s3c2410/usb-simtec.c . + + The `struct s3c2410_hcd_info` contains a pair of functions + that get called to enable over-current detection, and to + control the port power status. + + The ports are numbered 0 and 1. + + power_control: + + Called to enable or disable the power on the port. + + enable_oc: + + Called to enable or disable the over-current monitoring. + This should claim or release the resources being used to + check the power condition on the port, such as an IRQ. + + report_oc: + + The OHCI driver fills this field in for the over-current code + to call when there is a change to the over-current state on + an port. The ports argument is a bitmask of 1 bit per port, + with bit X being 1 for an over-current on port X. + + The function s3c2410_usb_report_oc() has been provided to + ensure this is called correctly. + + port[x]: + + This is struct describes each port, 0 or 1. The platform driver + should set the flags field of each port to S3C_HCDFLG_USED if + the port is enabled. + + + +Document Author +--------------- + +Ben Dooks, (c) 2005 Simtec Electronics diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 8b1430b4665..0665cb12bd6 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -135,3 +135,15 @@ Why: With the 16-bit PCMCIA subsystem now behaving (almost) like a pcmciautils package available at http://kernel.org/pub/linux/utils/kernel/pcmcia/ Who: Dominik Brodowski <linux@brodo.de> + +--------------------------- + +What: ip_queue and ip6_queue (old ipv4-only and ipv6-only netfilter queue) +When: December 2005 +Why: This interface has been obsoleted by the new layer3-independent + "nfnetlink_queue". The Kernel interface is compatible, so the old + ip[6]tables "QUEUE" targets still work and will transparently handle + all packets into nfnetlink queue number 0. Userspace users will have + to link against API-compatible library on top of libnfnetlink_queue + instead of the current 'libipq'. +Who: Harald Welte <laforge@netfilter.org> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index a998a8c2f95..3d5cd7a09b2 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -159,6 +159,11 @@ running once the system is up. acpi_fake_ecdt [HW,ACPI] Workaround failure due to BIOS lacking ECDT + acpi_generic_hotkey [HW,ACPI] + Allow consolidated generic hotkey driver to + over-ride platform specific driver. + See also Documentation/acpi-hotkey.txt. + ad1816= [HW,OSS] Format: <io>,<irq>,<dma>,<dma2> See also Documentation/sound/oss/AD1816. diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt new file mode 100644 index 00000000000..0541fe1de70 --- /dev/null +++ b/Documentation/kprobes.txt @@ -0,0 +1,588 @@ +Title : Kernel Probes (Kprobes) +Authors : Jim Keniston <jkenisto@us.ibm.com> + : Prasanna S Panchamukhi <prasanna@in.ibm.com> + +CONTENTS + +1. Concepts: Kprobes, Jprobes, Return Probes +2. Architectures Supported +3. Configuring Kprobes +4. API Reference +5. Kprobes Features and Limitations +6. Probe Overhead +7. TODO +8. Kprobes Example +9. Jprobes Example +10. Kretprobes Example + +1. Concepts: Kprobes, Jprobes, Return Probes + +Kprobes enables you to dynamically break into any kernel routine and +collect debugging and performance information non-disruptively. You +can trap at almost any kernel code address, specifying a handler +routine to be invoked when the breakpoint is hit. + +There are currently three types of probes: kprobes, jprobes, and +kretprobes (also called return probes). A kprobe can be inserted +on virtually any instruction in the kernel. A jprobe is inserted at +the entry to a kernel function, and provides convenient access to the +function's arguments. A return probe fires when a specified function +returns. + +In the typical case, Kprobes-based instrumentation is packaged as +a kernel module. The module's init function installs ("registers") +one or more probes, and the exit function unregisters them. A +registration function such as register_kprobe() specifies where +the probe is to be inserted and what handler is to be called when +the probe is hit. + +The next three subsections explain how the different types of +probes work. They explain certain things that you'll need to +know in order to make the best use of Kprobes -- e.g., the +difference between a pre_handler and a post_handler, and how +to use the maxactive and nmissed fields of a kretprobe. But +if you're in a hurry to start using Kprobes, you can skip ahead +to section 2. + +1.1 How Does a Kprobe Work? + +When a kprobe is registered, Kprobes makes a copy of the probed +instruction and replaces the first byte(s) of the probed instruction +with a breakpoint instruction (e.g., int3 on i386 and x86_64). + +When a CPU hits the breakpoint instruction, a trap occurs, the CPU's +registers are saved, and control passes to Kprobes via the +notifier_call_chain mechanism. Kprobes executes the "pre_handler" +associated with the kprobe, passing the handler the addresses of the +kprobe struct and the saved registers. + +Next, Kprobes single-steps its copy of the probed instruction. +(It would be simpler to single-step the actual instruction in place, +but then Kprobes would have to temporarily remove the breakpoint +instruction. This would open a small time window when another CPU +could sail right past the probepoint.) + +After the instruction is single-stepped, Kprobes executes the +"post_handler," if any, that is associated with the kprobe. +Execution then continues with the instruction following the probepoint. + +1.2 How Does a Jprobe Work? + +A jprobe is implemented using a kprobe that is placed on a function's +entry point. It employs a simple mirroring principle to allow +seamless access to the probed function's arguments. The jprobe +handler routine should have the same signature (arg list and return +type) as the function being probed, and must always end by calling +the Kprobes function jprobe_return(). + +Here's how it works. When the probe is hit, Kprobes makes a copy of +the saved registers and a generous portion of the stack (see below). +Kprobes then points the saved instruction pointer at the jprobe's +handler routine, and returns from the trap. As a result, control +passes to the handler, which is presented with the same register and +stack contents as the probed function. When it is done, the handler +calls jprobe_return(), which traps again to restore the original stack +contents and processor state and switch to the probed function. + +By convention, the callee owns its arguments, so gcc may produce code +that unexpectedly modifies that portion of the stack. This is why +Kprobes saves a copy of the stack and restores it after the jprobe +handler has run. Up to MAX_STACK_SIZE bytes are copied -- e.g., +64 bytes on i386. + +Note that the probed function's args may be passed on the stack +or in registers (e.g., for x86_64 or for an i386 fastcall function). +The jprobe will work in either case, so long as the handler's +prototype matches that of the probed function. + +1.3 How Does a Return Probe Work? + +When you call register_kretprobe(), Kprobes establishes a kprobe at +the entry to the function. When the probed function is called and this +probe is hit, Kprobes saves a copy of the return address, and replaces +the return address with the address of a "trampoline." The trampoline +is an arbitrary piece of code -- typically just a nop instruction. +At boot time, Kprobes registers a kprobe at the trampoline. + +When the probed function executes its return instruction, control +passes to the trampoline and that probe is hit. Kprobes' trampoline +handler calls the user-specified handler associated with the kretprobe, +then sets the saved instruction pointer to the saved return address, +and that's where execution resumes upon return from the trap. + +While the probed function is executing, its return address is +stored in an object of type kretprobe_instance. Before calling +register_kretprobe(), the user sets the maxactive field of the +kretprobe struct to specify how many instances of the specified +function can be probed simultaneously. register_kretprobe() +pre-allocates the indicated number of kretprobe_instance objects. + +For example, if the function is non-recursive and is called with a +spinlock held, maxactive = 1 should be enough. If the function is +non-recursive and can never relinquish the CPU (e.g., via a semaphore +or preemption), NR_CPUS should be enough. If maxactive <= 0, it is +set to a default value. If CONFIG_PREEMPT is enabled, the default +is max(10, 2*NR_CPUS). Otherwise, the default is NR_CPUS. + +It's not a disaster if you set maxactive too low; you'll just miss +some probes. In the kretprobe struct, the nmissed field is set to +zero when the return probe is registered, and is incremented every +time the probed function is entered but there is no kretprobe_instance +object available for establishing the return probe. + +2. Architectures Supported + +Kprobes, jprobes, and return probes are implemented on the following +architectures: + +- i386 +- x86_64 (AMD-64, E64MT) +- ppc64 +- ia64 (Support for probes on certain instruction types is still in progress.) +- sparc64 (Return probes not yet implemented.) + +3. Configuring Kprobes + +When configuring the kernel using make menuconfig/xconfig/oldconfig, +ensure that CONFIG_KPROBES is set to "y". Under "Kernel hacking", +look for "Kprobes". You may have to enable "Kernel debugging" +(CONFIG_DEBUG_KERNEL) before you can enable Kprobes. + +You may also want to ensure that CONFIG_KALLSYMS and perhaps even +CONFIG_KALLSYMS_ALL are set to "y", since kallsyms_lookup_name() +is a handy, version-independent way to find a function's address. + +If you need to insert a probe in the middle of a function, you may find +it useful to "Compile the kernel with debug info" (CONFIG_DEBUG_INFO), +so you can use "objdump -d -l vmlinux" to see the source-to-object +code mapping. + +4. API Reference + +The Kprobes API includes a "register" function and an "unregister" +function for each type of probe. Here are terse, mini-man-page +specifications for these functions and the associated probe handlers +that you'll write. See the latter half of this document for examples. + +4.1 register_kprobe + +#include <linux/kprobes.h> +int register_kprobe(struct kprobe *kp); + +Sets a breakpoint at the address kp->addr. When the breakpoint is +hit, Kprobes calls kp->pre_handler. After the probed instruction +is single-stepped, Kprobe calls kp->post_handler. If a fault +occurs during execution of kp->pre_handler or kp->post_handler, +or during single-stepping of the probed instruction, Kprobes calls +kp->fault_handler. Any or all handlers can be NULL. + +register_kprobe() returns 0 on success, or a negative errno otherwise. + +User's pre-handler (kp->pre_handler): +#include <linux/kprobes.h> +#include <linux/ptrace.h> +int pre_handler(struct kprobe *p, struct pt_regs *regs); + +Called with p pointing to the kprobe associated with the breakpoint, +and regs pointing to the struct containing the registers saved when +the breakpoint was hit. Return 0 here unless you're a Kprobes geek. + +User's post-handler (kp->post_handler): +#include <linux/kprobes.h> +#include <linux/ptrace.h> +void post_handler(struct kprobe *p, struct pt_regs *regs, + unsigned long flags); + +p and regs are as described for the pre_handler. flags always seems +to be zero. + +User's fault-handler (kp->fault_handler): +#include <linux/kprobes.h> +#include <linux/ptrace.h> +int fault_handler(struct kprobe *p, struct pt_regs *regs, int trapnr); + +p and regs are as described for the pre_handler. trapnr is the +architecture-specific trap number associated with the fault (e.g., +on i386, 13 for a general protection fault or 14 for a page fault). +Returns 1 if it successfully handled the exception. + +4.2 register_jprobe + +#include <linux/kprobes.h> +int register_jprobe(struct jprobe *jp) + +Sets a breakpoint at the address jp->kp.addr, which must be the address +of the first instruction of a function. When the breakpoint is hit, +Kprobes runs the handler whose address is jp->entry. + +The handler should have the same arg list and return type as the probed +function; and just before it returns, it must call jprobe_return(). +(The handler never actually returns, since jprobe_return() returns +control to Kprobes.) If the probed function is declared asmlinkage, +fastcall, or anything else that affects how args are passed, the +handler's declaration must match. + +register_jprobe() returns 0 on success, or a negative errno otherwise. + +4.3 register_kretprobe + +#include <linux/kprobes.h> +int register_kretprobe(struct kretprobe *rp); + +Establishes a return probe for the function whose address is +rp->kp.addr. When that function returns, Kprobes calls rp->handler. +You must set rp->maxactive appropriately before you call +register_kretprobe(); see "How Does a Return Probe Work?" for details. + +register_kretprobe() returns 0 on success, or a negative errno +otherwise. + +User's return-probe handler (rp->handler): +#include <linux/kprobes.h> +#include <linux/ptrace.h> +int kretprobe_handler(struct kretprobe_instance *ri, struct pt_regs *regs); + +regs is as described for kprobe.pre_handler. ri points to the +kretprobe_instance object, of which the following fields may be +of interest: +- ret_addr: the return address +- rp: points to the corresponding kretprobe object +- task: points to the corresponding task struct +The handler's return value is currently ignored. + +4.4 unregister_*probe + +#include <linux/kprobes.h> +void unregister_kprobe(struct kprobe *kp); +void unregister_jprobe(struct jprobe *jp); +void unregister_kretprobe(struct kretprobe *rp); + +Removes the specified probe. The unregister function can be called +at any time after the probe has been registered. + +5. Kprobes Features and Limitations + +As of Linux v2.6.12, Kprobes allows multiple probes at the same +address. Currently, however, there cannot be multiple jprobes on +the same function at the same time. + +In general, you can install a probe anywhere in the kernel. +In particular, you can probe interrupt handlers. Known exceptions +are discussed in this section. + +For obvious reasons, it's a bad idea to install a probe in +the code that implements Kprobes (mostly kernel/kprobes.c and +arch/*/kernel/kprobes.c). A patch in the v2.6.13 timeframe instructs +Kprobes to reject such requests. + +If you install a probe in an inline-able function, Kprobes makes +no attempt to chase down all inline instances of the function and +install probes there. gcc may inline a function without being asked, +so keep this in mind if you're not seeing the probe hits you expect. + +A probe handler can modify the environment of the probed function +-- e.g., by modifying kernel data structures, or by modifying the +contents of the pt_regs struct (which are restored to the registers +upon return from the breakpoint). So Kprobes can be used, for example, +to install a bug fix or to inject faults for testing. Kprobes, of +course, has no way to distinguish the deliberately injected faults +from the accidental ones. Don't drink and probe. + +Kprobes makes no attempt to prevent probe handlers from stepping on +each other -- e.g., probing printk() and then calling printk() from a +probe handler. As of Linux v2.6.12, if a probe handler hits a probe, +that second probe's handlers won't be run in that instance. + +In Linux v2.6.12 and previous versions, Kprobes' data structures are +protected by a single lock that is held during probe registration and +unregistration and while handlers are run. Thus, no two handlers +can run simultaneously. To improve scalability on SMP systems, +this restriction will probably be removed soon, in which case +multiple handlers (or multiple instances of the same handler) may +run concurrently on different CPUs. Code your handlers accordingly. + +Kprobes does not use semaphores or allocate memory except during +registration and unregistration. + +Probe handlers are run with preemption disabled. Depending on the +architecture, handlers may also run with interrupts disabled. In any +case, your handler should not yield the CPU (e.g., by attempting to +acquire a semaphore). + +Since a return probe is implemented by replacing the return +address with the trampoline's address, stack backtraces and calls +to __builtin_return_address() will typically yield the trampoline's +address instead of the real return address for kretprobed functions. +(As far as we can tell, __builtin_return_address() is used only +for instrumentation and error reporting.) + +If the number of times a function is called does not match the +number of times it returns, registering a return probe on that +function may produce undesirable results. We have the do_exit() +and do_execve() cases covered. do_fork() is not an issue. We're +unaware of other specific cases where this could be a problem. + +6. Probe Overhead + +On a typical CPU in use in 2005, a kprobe hit takes 0.5 to 1.0 +microseconds to process. Specifically, a benchmark that hits the same +probepoint repeatedly, firing a simple handler each time, reports 1-2 +million hits per second, depending on the architecture. A jprobe or +return-probe hit typically takes 50-75% longer than a kprobe hit. +When you have a return probe set on a function, adding a kprobe at +the entry to that function adds essentially no overhead. + +Here are sample overhead figures (in usec) for different architectures. +k = kprobe; j = jprobe; r = return probe; kr = kprobe + return probe +on same function; jr = jprobe + return probe on same function + +i386: Intel Pentium M, 1495 MHz, 2957.31 bogomips +k = 0.57 usec; j = 1.00; r = 0.92; kr = 0.99; jr = 1.40 + +x86_64: AMD Opteron 246, 1994 MHz, 3971.48 bogomips +k = 0.49 usec; j = 0.76; r = 0.80; kr = 0.82; jr = 1.07 + +ppc64: POWER5 (gr), 1656 MHz (SMT disabled, 1 virtual CPU per physical CPU) +k = 0.77 usec; j = 1.31; r = 1.26; kr = 1.45; jr = 1.99 + +7. TODO + +a. SystemTap (http://sourceware.org/systemtap): Work in progress +to provide a simplified programming interface for probe-based +instrumentation. +b. Improved SMP scalability: Currently, work is in progress to handle +multiple kprobes in parallel. +c. Kernel return probes for sparc64. +d. Support for other architectures. +e. User-space probes. + +8. Kprobes Example + +Here's a sample kernel module showing the use of kprobes to dump a +stack trace and selected i386 registers when do_fork() is called. +----- cut here ----- +/*kprobe_example.c*/ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/kprobes.h> +#include <linux/kallsyms.h> +#include <linux/sched.h> + +/*For each probe you need to allocate a kprobe structure*/ +static struct kprobe kp; + +/*kprobe pre_handler: called just before the probed instruction is executed*/ +int handler_pre(struct kprobe *p, struct pt_regs *regs) +{ + printk("pre_handler: p->addr=0x%p, eip=%lx, eflags=0x%lx\n", + p->addr, regs->eip, regs->eflags); + dump_stack(); + return 0; +} + +/*kprobe post_handler: called after the probed instruction is executed*/ +void handler_post(struct kprobe *p, struct pt_regs *regs, unsigned long flags) +{ + printk("post_handler: p->addr=0x%p, eflags=0x%lx\n", + p->addr, regs->eflags); +} + +/* fault_handler: this is called if an exception is generated for any + * instruction within the pre- or post-handler, or when Kprobes + * single-steps the probed instruction. + */ +int handler_fault(struct kprobe *p, struct pt_regs *regs, int trapnr) +{ + printk("fault_handler: p->addr=0x%p, trap #%dn", + p->addr, trapnr); + /* Return 0 because we don't handle the fault. */ + return 0; +} + +int init_module(void) +{ + int ret; + kp.pre_handler = handler_pre; + kp.post_handler = handler_post; + kp.fault_handler = handler_fault; + kp.addr = (kprobe_opcode_t*) kallsyms_lookup_name("do_fork"); + /* register the kprobe now */ + if (!kp.addr) { + printk("Couldn't find %s to plant kprobe\n", "do_fork"); + return -1; + } + if ((ret = register_kprobe(&kp) < 0)) { + printk("register_kprobe failed, returned %d\n", ret); + return -1; + } + printk("kprobe registered\n"); + return 0; +} + +void cleanup_module(void) +{ + unregister_kprobe(&kp); + printk("kprobe unregistered\n"); +} + +MODULE_LICENSE("GPL"); +----- cut here ----- + +You can build the kernel module, kprobe-example.ko, using the following +Makefile: +----- cut here ----- +obj-m := kprobe-example.o +KDIR := /lib/modules/$(shell uname -r)/build +PWD := $(shell pwd) +default: + $(MAKE) -C $(KDIR) SUBDIRS=$(PWD) modules +clean: + rm -f *.mod.c *.ko *.o +----- cut here ----- + +$ make +$ su - +... +# insmod kprobe-example.ko + +You will see the trace data in /var/log/messages and on the console +whenever do_fork() is invoked to create a new process. + +9. Jprobes Example + +Here's a sample kernel module showing the use of jprobes to dump +the arguments of do_fork(). +----- cut here ----- +/*jprobe-example.c */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/uio.h> +#include <linux/kprobes.h> +#include <linux/kallsyms.h> + +/* + * Jumper probe for do_fork. + * Mirror principle enables access to arguments of the probed routine + * from the probe handler. + */ + +/* Proxy routine having the same arguments as actual do_fork() routine */ +long jdo_fork(unsigned long clone_flags, unsigned long stack_start, + struct pt_regs *regs, unsigned long stack_size, + int __user * parent_tidptr, int __user * child_tidptr) +{ + printk("jprobe: clone_flags=0x%lx, stack_size=0x%lx, regs=0x%p\n", + clone_flags, stack_size, regs); + /* Always end with a call to jprobe_return(). */ + jprobe_return(); + /*NOTREACHED*/ + return 0; +} + +static struct jprobe my_jprobe = { + .entry = (kprobe_opcode_t *) jdo_fork +}; + +int init_module(void) +{ + int ret; + my_jprobe.kp.addr = (kprobe_opcode_t *) kallsyms_lookup_name("do_fork"); + if (!my_jprobe.kp.addr) { + printk("Couldn't find %s to plant jprobe\n", "do_fork"); + return -1; + } + + if ((ret = register_jprobe(&my_jprobe)) <0) { + printk("register_jprobe failed, returned %d\n", ret); + return -1; + } + printk("Planted jprobe at %p, handler addr %p\n", + my_jprobe.kp.addr, my_jprobe.entry); + return 0; +} + +void cleanup_module(void) +{ + unregister_jprobe(&my_jprobe); + printk("jprobe unregistered\n"); +} + +MODULE_LICENSE("GPL"); +----- cut here ----- + +Build and insert the kernel module as shown in the above kprobe +example. You will see the trace data in /var/log/messages and on +the console whenever do_fork() is invoked to create a new process. +(Some messages may be suppressed if syslogd is configured to +eliminate duplicate messages.) + +10. Kretprobes Example + +Here's a sample kernel module showing the use of return probes to +report failed calls to sys_open(). +----- cut here ----- +/*kretprobe-example.c*/ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/kprobes.h> +#include <linux/kallsyms.h> + +static const char *probed_func = "sys_open"; + +/* Return-probe handler: If the probed function fails, log the return value. */ +static int ret_handler(struct kretprobe_instance *ri, struct pt_regs *regs) +{ + // Substitute the appropriate register name for your architecture -- + // e.g., regs->rax for x86_64, regs->gpr[3] for ppc64. + int retval = (int) regs->eax; + if (retval < 0) { + printk("%s returns %d\n", probed_func, retval); + } + return 0; +} + +static struct kretprobe my_kretprobe = { + .handler = ret_handler, + /* Probe up to 20 instances concurrently. */ + .maxactive = 20 +}; + +int init_module(void) +{ + int ret; + my_kretprobe.kp.addr = + (kprobe_opcode_t *) kallsyms_lookup_name(probed_func); + if (!my_kretprobe.kp.addr) { + printk("Couldn't find %s to plant return probe\n", probed_func); + return -1; + } + if ((ret = register_kretprobe(&my_kretprobe)) < 0) { + printk("register_kretprobe failed, returned %d\n", ret); + return -1; + } + printk("Planted return probe at %p\n", my_kretprobe.kp.addr); + return 0; +} + +void cleanup_module(void) +{ + unregister_kretprobe(&my_kretprobe); + printk("kretprobe unregistered\n"); + /* nmissed > 0 suggests that maxactive was set too low. */ + printk("Missed probing %d instances of %s\n", + my_kretprobe.nmissed, probed_func); +} + +MODULE_LICENSE("GPL"); +----- cut here ----- + +Build and insert the kernel module as shown in the above kprobe +example. You will see the trace data in /var/log/messages and on the +console whenever sys_open() returns a negative value. (Some messages +may be suppressed if syslogd is configured to eliminate duplicate +messages.) + +For additional information on Kprobes, refer to the following URLs: +http://www-106.ibm.com/developerworks/library/l-kprobes.html?ca=dgr-lnxw42Kprobe +http://www.redhat.com/magazine/005mar05/features/kprobes/ diff --git a/Documentation/networking/cxgb.txt b/Documentation/networking/cxgb.txt new file mode 100644 index 00000000000..76324638626 --- /dev/null +++ b/Documentation/networking/cxgb.txt @@ -0,0 +1,352 @@ + Chelsio N210 10Gb Ethernet Network Controller + + Driver Release Notes for Linux + + Version 2.1.1 + + June 20, 2005 + +CONTENTS +======== + INTRODUCTION + FEATURES + PERFORMANCE + DRIVER MESSAGES + KNOWN ISSUES + SUPPORT + + +INTRODUCTION +============ + + This document describes the Linux driver for Chelsio 10Gb Ethernet Network + Controller. This driver supports the Chelsio N210 NIC and is backward + compatible with the Chelsio N110 model 10Gb NICs. + + +FEATURES +======== + + Adaptive Interrupts (adaptive-rx) + --------------------------------- + + This feature provides an adaptive algorithm that adjusts the interrupt + coalescing parameters, allowing the driver to dynamically adapt the latency + settings to achieve the highest performance during various types of network + load. + + The interface used to control this feature is ethtool. Please see the + ethtool manpage for additional usage information. + + By default, adaptive-rx is disabled. + To enable adaptive-rx: + + ethtool -C <interface> adaptive-rx on + + To disable adaptive-rx, use ethtool: + + ethtool -C <interface> adaptive-rx off + + After disabling adaptive-rx, the timer latency value will be set to 50us. + You may set the timer latency after disabling adaptive-rx: + + ethtool -C <interface> rx-usecs <microseconds> + + An example to set the timer latency value to 100us on eth0: + + ethtool -C eth0 rx-usecs 100 + + You may also provide a timer latency value while disabling adpative-rx: + + ethtool -C <interface> adaptive-rx off rx-usecs <microseconds> + + If adaptive-rx is disabled and a timer latency value is specified, the timer + will be set to the specified value until changed by the user or until + adaptive-rx is enabled. + + To view the status of the adaptive-rx and timer latency values: + + ethtool -c <interface> + + + TCP Segmentation Offloading (TSO) Support + ----------------------------------------- + + This feature, also known as "large send", enables a system's protocol stack + to offload portions of outbound TCP processing to a network interface card + thereby reducing system CPU utilization and enhancing performance. + + The interface used to control this feature is ethtool version 1.8 or higher. + Please see the ethtool manpage for additional usage information. + + By default, TSO is enabled. + To disable TSO: + + ethtool -K <interface> tso off + + To enable TSO: + + ethtool -K <interface> tso on + + To view the status of TSO: + + ethtool -k <interface> + + +PERFORMANCE +=========== + + The following information is provided as an example of how to change system + parameters for "performance tuning" an what value to use. You may or may not + want to change these system parameters, depending on your server/workstation + application. Doing so is not warranted in any way by Chelsio Communications, + and is done at "YOUR OWN RISK". Chelsio will not be held responsible for loss + of data or damage to equipment. + + Your distribution may have a different way of doing things, or you may prefer + a different method. These commands are shown only to provide an example of + what to do and are by no means definitive. + + Making any of the following system changes will only last until you reboot + your system. You may want to write a script that runs at boot-up which + includes the optimal settings for your system. + + Setting PCI Latency Timer: + setpci -d 1425:* 0x0c.l=0x0000F800 + + Disabling TCP timestamp: + sysctl -w net.ipv4.tcp_timestamps=0 + + Disabling SACK: + sysctl -w net.ipv4.tcp_sack=0 + + Setting large number of incoming connection requests: + sysctl -w net.ipv4.tcp_max_syn_backlog=3000 + + Setting maximum receive socket buffer size: + sysctl -w net.core.rmem_max=1024000 + + Setting maximum send socket buffer size: + sysctl -w net.core.wmem_max=1024000 + + Set smp_affinity (on a multiprocessor system) to a single CPU: + echo 1 > /proc/irq/<interrupt_number>/smp_affinity + + Setting default receive socket buffer size: + sysctl -w net.core.rmem_default=524287 + + Setting default send socket buffer size: + sysctl -w net.core.wmem_default=524287 + + Setting maximum option memory buffers: + sysctl -w net.core.optmem_max=524287 + + Setting maximum backlog (# of unprocessed packets before kernel drops): + sysctl -w net.core.netdev_max_backlog=300000 + + Setting TCP read buffers (min/default/max): + sysctl -w net.ipv4.tcp_rmem="10000000 10000000 10000000" + + Setting TCP write buffers (min/pressure/max): + sysctl -w net.ipv4.tcp_wmem="10000000 10000000 10000000" + + Setting TCP buffer space (min/pressure/max): + sysctl -w net.ipv4.tcp_mem="10000000 10000000 10000000" + + TCP window size for single connections: + The receive buffer (RX_WINDOW) size must be at least as large as the + Bandwidth-Delay Product of the communication link between the sender and + receiver. Due to the variations of RTT, you may want to increase the buffer + size up to 2 times the Bandwidth-Delay Product. Reference page 289 of + "TCP/IP Illustrated, Volume 1, The Protocols" by W. Richard Stevens. + At 10Gb speeds, use the following formula: + RX_WINDOW >= 1.25MBytes * RTT(in milliseconds) + Example for RTT with 100us: RX_WINDOW = (1,250,000 * 0.1) = 125,000 + RX_WINDOW sizes of 256KB - 512KB should be sufficient. + Setting the min, max, and default receive buffer (RX_WINDOW) size: + sysctl -w net.ipv4.tcp_rmem="<min> <default> <max>" + + TCP window size for multiple connections: + The receive buffer (RX_WINDOW) size may be calculated the same as single + connections, but should be divided by the number of connections. The + smaller window prevents congestion and facilitates better pacing, + especially if/when MAC level flow control does not work well or when it is + not supported on the machine. Experimentation may be necessary to attain + the correct value. This method is provided as a starting point fot the + correct receive buffer size. + Setting the min, max, and default receive buffer (RX_WINDOW) size is + performed in the same manner as single connection. + + +DRIVER MESSAGES +=============== + + The following messages are the most common messages logged by syslog. These + may be found in /var/log/messages. + + Driver up: + Chelsio Network Driver - version 2.1.1 + + NIC detected: + eth#: Chelsio N210 1x10GBaseX NIC (rev #), PCIX 133MHz/64-bit + + Link up: + eth#: link is up at 10 Gbps, full duplex + + Link down: + eth#: link is down + + +KNOWN ISSUES +============ + + These issues have been identified during testing. The following information + is provided as a workaround to the problem. In some cases, this problem is + inherent to Linux or to a particular Linux Distribution and/or hardware + platform. + + 1. Large number of TCP retransmits on a multiprocessor (SMP) system. + + On a system with multiple CPUs, the interrupt (IRQ) for the network + controller may be bound to more than one CPU. This will cause TCP + retransmits if the packet data were to be split across different CPUs + and re-assembled in a different order than expected. + + To eliminate the TCP retransmits, set smp_affinity on the particular + interrupt to a single CPU. You can locate the interrupt (IRQ) used on + the N110/N210 by using ifconfig: + ifconfig <dev_name> | grep Interrupt + Set the smp_affinity to a single CPU: + echo 1 > /proc/irq/<interrupt_number>/smp_affinity + + It is highly suggested that you do not run the irqbalance daemon on your + system, as this will change any smp_affinity setting you have applied. + The irqbalance daemon runs on a 10 second interval and binds interrupts + to the least loaded CPU determined by the daemon. To disable this daemon: + chkconfig --level 2345 irqbalance off + + By default, some Linux distributions enable the kernel feature, + irqbalance, which performs the same function as the daemon. To disable + this feature, add the following line to your bootloader: + noirqbalance + + Example using the Grub bootloader: + title Red Hat Enterprise Linux AS (2.4.21-27.ELsmp) + root (hd0,0) + kernel /vmlinuz-2.4.21-27.ELsmp ro root=/dev/hda3 noirqbalance + initrd /initrd-2.4.21-27.ELsmp.img + + 2. After running insmod, the driver is loaded and the incorrect network + interface is brought up without running ifup. + + When using 2.4.x kernels, including RHEL kernels, the Linux kernel + invokes a script named "hotplug". This script is primarily used to + automatically bring up USB devices when they are plugged in, however, + the script also attempts to automatically bring up a network interface + after loading the kernel module. The hotplug script does this by scanning + the ifcfg-eth# config files in /etc/sysconfig/network-scripts, looking + for HWADDR=<mac_address>. + + If the hotplug script does not find the HWADDRR within any of the + ifcfg-eth# files, it will bring up the device with the next available + interface name. If this interface is already configured for a different + network card, your new interface will have incorrect IP address and + network settings. + + To solve this issue, you can add the HWADDR=<mac_address> key to the + interface config file of your network controller. + + To disable this "hotplug" feature, you may add the driver (module name) + to the "blacklist" file located in /etc/hotplug. It has been noted that + this does not work for network devices because the net.agent script + does not use the blacklist file. Simply remove, or rename, the net.agent + script located in /etc/hotplug to disable this feature. + + 3. Transport Protocol (TP) hangs when running heavy multi-connection traffic + on an AMD Opteron system with HyperTransport PCI-X Tunnel chipset. + + If your AMD Opteron system uses the AMD-8131 HyperTransport PCI-X Tunnel + chipset, you may experience the "133-Mhz Mode Split Completion Data + Corruption" bug identified by AMD while using a 133Mhz PCI-X card on the + bus PCI-X bus. + + AMD states, "Under highly specific conditions, the AMD-8131 PCI-X Tunnel + can provide stale data via split completion cycles to a PCI-X card that + is operating at 133 Mhz", causing data corruption. + + AMD's provides three workarounds for this problem, however, Chelsio + recommends the first option for best performance with this bug: + + For 133Mhz secondary bus operation, limit the transaction length and + the number of outstanding transactions, via BIOS configuration + programming of the PCI-X card, to the following: + + Data Length (bytes): 1k + Total allowed outstanding transactions: 2 + + Please refer to AMD 8131-HT/PCI-X Errata 26310 Rev 3.08 August 2004, + section 56, "133-MHz Mode Split Completion Data Corruption" for more + details with this bug and workarounds suggested by AMD. + + It may be possible to work outside AMD's recommended PCI-X settings, try + increasing the Data Length to 2k bytes for increased performance. If you + have issues with these settings, please revert to the "safe" settings + and duplicate the problem before submitting a bug or asking for support. + + NOTE: The default setting on most systems is 8 outstanding transactions + and 2k bytes data length. + + 4. On multiprocessor systems, it has been noted that an application which + is handling 10Gb networking can switch between CPUs causing degraded + and/or unstable performance. + + If running on an SMP system and taking performance measurements, it + is suggested you either run the latest netperf-2.4.0+ or use a binding + tool such as Tim Hockin's procstate utilities (runon) + <http://www.hockin.org/~thockin/procstate/>. + + Binding netserver and netperf (or other applications) to particular + CPUs will have a significant difference in performance measurements. + You may need to experiment which CPU to bind the application to in + order to achieve the best performance for your system. + + If you are developing an application designed for 10Gb networking, + please keep in mind you may want to look at kernel functions + sched_setaffinity & sched_getaffinity to bind your application. + + If you are just running user-space applications such as ftp, telnet, + etc., you may want to try the runon tool provided by Tim Hockin's + procstate utility. You could also try binding the interface to a + particular CPU: runon 0 ifup eth0 + + +SUPPORT +======= + + If you have problems with the software or hardware, please contact our + customer support team via email at support@chelsio.com or check our website + at http://www.chelsio.com + +=============================================================================== + + Chelsio Communications + 370 San Aleso Ave. + Suite 100 + Sunnyvale, CA 94085 + http://www.chelsio.com + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License, version 2, as +published by the Free Software Foundation. + +You should have received a copy of the GNU General Public License along +with this program; if not, write to the Free Software Foundation, Inc., +59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + +THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED +WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF +MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. + + Copyright (c) 2003-2005 Chelsio Communications. All rights reserved. + +=============================================================================== diff --git a/Documentation/networking/phy.txt b/Documentation/networking/phy.txt new file mode 100644 index 00000000000..29ccae40903 --- /dev/null +++ b/Documentation/networking/phy.txt @@ -0,0 +1,288 @@ + +------- +PHY Abstraction Layer +(Updated 2005-07-21) + +Purpose + + Most network devices consist of set of registers which provide an interface + to a MAC layer, which communicates with the physical connection through a + PHY. The PHY concerns itself with negotiating link parameters with the link + partner on the other side of the network connection (typically, an ethernet + cable), and provides a register interface to allow drivers to determine what + settings were chosen, and to configure what settings are allowed. + + While these devices are distinct from the network devices, and conform to a + standard layout for the registers, it has been common practice to integrate + the PHY management code with the network driver. This has resulted in large + amounts of redundant code. Also, on embedded systems with multiple (and + sometimes quite different) ethernet controllers connected to the same + management bus, it is difficult to ensure safe use of the bus. + + Since the PHYs are devices, and the management busses through which they are + accessed are, in fact, busses, the PHY Abstraction Layer treats them as such. + In doing so, it has these goals: + + 1) Increase code-reuse + 2) Increase overall code-maintainability + 3) Speed development time for new network drivers, and for new systems + + Basically, this layer is meant to provide an interface to PHY devices which + allows network driver writers to write as little code as possible, while + still providing a full feature set. + +The MDIO bus + + Most network devices are connected to a PHY by means of a management bus. + Different devices use different busses (though some share common interfaces). + In order to take advantage of the PAL, each bus interface needs to be + registered as a distinct device. + + 1) read and write functions must be implemented. Their prototypes are: + + int write(struct mii_bus *bus, int mii_id, int regnum, u16 value); + int read(struct mii_bus *bus, int mii_id, int regnum); + + mii_id is the address on the bus for the PHY, and regnum is the register + number. These functions are guaranteed not to be called from interrupt + time, so it is safe for them to block, waiting for an interrupt to signal + the operation is complete + + 2) A reset function is necessary. This is used to return the bus to an + initialized state. + + 3) A probe function is needed. This function should set up anything the bus + driver needs, setup the mii_bus structure, and register with the PAL using + mdiobus_register. Similarly, there's a remove function to undo all of + that (use mdiobus_unregister). + + 4) Like any driver, the device_driver structure must be configured, and init + exit functions are used to register the driver. + + 5) The bus must also be declared somewhere as a device, and registered. + + As an example for how one driver implemented an mdio bus driver, see + drivers/net/gianfar_mii.c and arch/ppc/syslib/mpc85xx_devices.c + +Connecting to a PHY + + Sometime during startup, the network driver needs to establish a connection + between the PHY device, and the network device. At this time, the PHY's bus + and drivers need to all have been loaded, so it is ready for the connection. + At this point, there are several ways to connect to the PHY: + + 1) The PAL handles everything, and only calls the network driver when + the link state changes, so it can react. + + 2) The PAL handles everything except interrupts (usually because the + controller has the interrupt registers). + + 3) The PAL handles everything, but checks in with the driver every second, + allowing the network driver to react first to any changes before the PAL + does. + + 4) The PAL serves only as a library of functions, with the network device + manually calling functions to update status, and configure the PHY + + +Letting the PHY Abstraction Layer do Everything + + If you choose option 1 (The hope is that every driver can, but to still be + useful to drivers that can't), connecting to the PHY is simple: + + First, you need a function to react to changes in the link state. This + function follows this protocol: + + static void adjust_link(struct net_device *dev); + + Next, you need to know the device name of the PHY connected to this device. + The name will look something like, "phy0:0", where the first number is the + bus id, and the second is the PHY's address on that bus. + + Now, to connect, just call this function: + + phydev = phy_connect(dev, phy_name, &adjust_link, flags); + + phydev is a pointer to the phy_device structure which represents the PHY. If + phy_connect is successful, it will return the pointer. dev, here, is the + pointer to your net_device. Once done, this function will have started the + PHY's software state machine, and registered for the PHY's interrupt, if it + has one. The phydev structure will be populated with information about the + current state, though the PHY will not yet be truly operational at this + point. + + flags is a u32 which can optionally contain phy-specific flags. + This is useful if the system has put hardware restrictions on + the PHY/controller, of which the PHY needs to be aware. + + Now just make sure that phydev->supported and phydev->advertising have any + values pruned from them which don't make sense for your controller (a 10/100 + controller may be connected to a gigabit capable PHY, so you would need to + mask off SUPPORTED_1000baseT*). See include/linux/ethtool.h for definitions + for these bitfields. Note that you should not SET any bits, or the PHY may + get put into an unsupported state. + + Lastly, once the controller is ready to handle network traffic, you call + phy_start(phydev). This tells the PAL that you are ready, and configures the + PHY to connect to the network. If you want to handle your own interrupts, + just set phydev->irq to PHY_IGNORE_INTERRUPT before you call phy_start. + Similarly, if you don't want to use interrupts, set phydev->irq to PHY_POLL. + + When you want to disconnect from the network (even if just briefly), you call + phy_stop(phydev). + +Keeping Close Tabs on the PAL + + It is possible that the PAL's built-in state machine needs a little help to + keep your network device and the PHY properly in sync. If so, you can + register a helper function when connecting to the PHY, which will be called + every second before the state machine reacts to any changes. To do this, you + need to manually call phy_attach() and phy_prepare_link(), and then call + phy_start_machine() with the second argument set to point to your special + handler. + + Currently there are no examples of how to use this functionality, and testing + on it has been limited because the author does not have any drivers which use + it (they all use option 1). So Caveat Emptor. + +Doing it all yourself + + There's a remote chance that the PAL's built-in state machine cannot track + the complex interactions between the PHY and your network device. If this is + so, you can simply call phy_attach(), and not call phy_start_machine or + phy_prepare_link(). This will mean that phydev->state is entirely yours to + handle (phy_start and phy_stop toggle between some of the states, so you + might need to avoid them). + + An effort has been made to make sure that useful functionality can be + accessed without the state-machine running, and most of these functions are + descended from functions which did not interact with a complex state-machine. + However, again, no effort has been made so far to test running without the + state machine, so tryer beware. + + Here is a brief rundown of the functions: + + int phy_read(struct phy_device *phydev, u16 regnum); + int phy_write(struct phy_device *phydev, u16 regnum, u16 val); + + Simple read/write primitives. They invoke the bus's read/write function + pointers. + + void phy_print_status(struct phy_device *phydev); + + A convenience function to print out the PHY status neatly. + + int phy_clear_interrupt(struct phy_device *phydev); + int phy_config_interrupt(struct phy_device *phydev, u32 interrupts); + + Clear the PHY's interrupt, and configure which ones are allowed, + respectively. Currently only supports all on, or all off. + + int phy_enable_interrupts(struct phy_device *phydev); + int phy_disable_interrupts(struct phy_device *phydev); + + Functions which enable/disable PHY interrupts, clearing them + before and after, respectively. + + int phy_start_interrupts(struct phy_device *phydev); + int phy_stop_interrupts(struct phy_device *phydev); + + Requests the IRQ for the PHY interrupts, then enables them for + start, or disables then frees them for stop. + + struct phy_device * phy_attach(struct net_device *dev, const char *phy_id, + u32 flags); + + Attaches a network device to a particular PHY, binding the PHY to a generic + driver if none was found during bus initialization. Passes in + any phy-specific flags as needed. + + int phy_start_aneg(struct phy_device *phydev); + + Using variables inside the phydev structure, either configures advertising + and resets autonegotiation, or disables autonegotiation, and configures + forced settings. + + static inline int phy_read_status(struct phy_device *phydev); + + Fills the phydev structure with up-to-date information about the current + settings in the PHY. + + void phy_sanitize_settings(struct phy_device *phydev) + + Resolves differences between currently desired settings, and + supported settings for the given PHY device. Does not make + the changes in the hardware, though. + + int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd); + int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd); + + Ethtool convenience functions. + + int phy_mii_ioctl(struct phy_device *phydev, + struct mii_ioctl_data *mii_data, int cmd); + + The MII ioctl. Note that this function will completely screw up the state + machine if you write registers like BMCR, BMSR, ADVERTISE, etc. Best to + use this only to write registers which are not standard, and don't set off + a renegotiation. + + +PHY Device Drivers + + With the PHY Abstraction Layer, adding support for new PHYs is + quite easy. In some cases, no work is required at all! However, + many PHYs require a little hand-holding to get up-and-running. + +Generic PHY driver + + If the desired PHY doesn't have any errata, quirks, or special + features you want to support, then it may be best to not add + support, and let the PHY Abstraction Layer's Generic PHY Driver + do all of the work. + +Writing a PHY driver + + If you do need to write a PHY driver, the first thing to do is + make sure it can be matched with an appropriate PHY device. + This is done during bus initialization by reading the device's + UID (stored in registers 2 and 3), then comparing it to each + driver's phy_id field by ANDing it with each driver's + phy_id_mask field. Also, it needs a name. Here's an example: + + static struct phy_driver dm9161_driver = { + .phy_id = 0x0181b880, + .name = "Davicom DM9161E", + .phy_id_mask = 0x0ffffff0, + ... + } + + Next, you need to specify what features (speed, duplex, autoneg, + etc) your PHY device and driver support. Most PHYs support + PHY_BASIC_FEATURES, but you can look in include/mii.h for other + features. + + Each driver consists of a number of function pointers: + + config_init: configures PHY into a sane state after a reset. + For instance, a Davicom PHY requires descrambling disabled. + probe: Does any setup needed by the driver + suspend/resume: power management + config_aneg: Changes the speed/duplex/negotiation settings + read_status: Reads the current speed/duplex/negotiation settings + ack_interrupt: Clear a pending interrupt + config_intr: Enable or disable interrupts + remove: Does any driver take-down + + Of these, only config_aneg and read_status are required to be + assigned by the driver code. The rest are optional. Also, it is + preferred to use the generic phy driver's versions of these two + functions if at all possible: genphy_read_status and + genphy_config_aneg. If this is not possible, it is likely that + you only need to perform some actions before and after invoking + these functions, and so your functions will wrap the generic + ones. + + Feel free to look at the Marvell, Cicada, and Davicom drivers in + drivers/net/phy/ for examples (the lxt and qsemi drivers have + not been tested as of this writing) diff --git a/Documentation/pci.txt b/Documentation/pci.txt index 62b1dc5d97e..76d28d03365 100644 --- a/Documentation/pci.txt +++ b/Documentation/pci.txt @@ -266,20 +266,6 @@ port an old driver to the new PCI interface. They are no longer present in the kernel as they aren't compatible with hotplug or PCI domains or having sane locking. -pcibios_present() and Since ages, you don't need to test presence -pci_present() of PCI subsystem when trying to talk to it. - If it's not there, the list of PCI devices - is empty and all functions for searching for - devices just return NULL. -pcibios_(read|write)_* Superseded by their pci_(read|write)_* - counterparts. -pcibios_find_* Superseded by their pci_get_* counterparts. -pci_for_each_dev() Superseded by pci_get_device() -pci_for_each_dev_reverse() Superseded by pci_find_device_reverse() -pci_for_each_bus() Superseded by pci_find_next_bus() pci_find_device() Superseded by pci_get_device() pci_find_subsys() Superseded by pci_get_subsys() pci_find_slot() Superseded by pci_get_slot() -pcibios_find_class() Superseded by pci_get_class() -pci_find_class() Superseded by pci_get_class() -pci_(read|write)_*_nodev() Superseded by pci_bus_(read|write)_*() diff --git a/Documentation/serial/driver b/Documentation/serial/driver index ac7eabbf662..87856d3cfb6 100644 --- a/Documentation/serial/driver +++ b/Documentation/serial/driver @@ -111,24 +111,17 @@ hardware. Interrupts: locally disabled. This call must not sleep - stop_tx(port,tty_stop) + stop_tx(port) Stop transmitting characters. This might be due to the CTS line becoming inactive or the tty layer indicating we want - to stop transmission. - - tty_stop: 1 if this call is due to the TTY layer issuing a - TTY stop to the driver (equiv to rs_stop). + to stop transmission due to an XOFF character. Locking: port->lock taken. Interrupts: locally disabled. This call must not sleep - start_tx(port,tty_start) - start transmitting characters. (incidentally, nonempty will - always be nonzero, and shouldn't be used - it will be dropped). - - tty_start: 1 if this call was due to the TTY layer issuing - a TTY start to the driver (equiv to rs_start) + start_tx(port) + start transmitting characters. Locking: port->lock taken. Interrupts: locally disabled. diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt index a18ecb92b35..5c49ba07e70 100644 --- a/Documentation/sound/alsa/ALSA-Configuration.txt +++ b/Documentation/sound/alsa/ALSA-Configuration.txt @@ -132,6 +132,7 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed. mpu_irq - IRQ # for MPU-401 UART (PnP setup) dma1 - first DMA # for AD1816A chip (PnP setup) dma2 - second DMA # for AD1816A chip (PnP setup) + clockfreq - Clock frequency for AD1816A chip (default = 0, 33000Hz) Module supports up to 8 cards, autoprobe and PnP. diff --git a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl index db0b7d2dc47..0475478c248 100644 --- a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl +++ b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl @@ -3422,10 +3422,17 @@ struct _snd_pcm_runtime { <para> The <structfield>iface</structfield> field specifies the type of - the control, - <constant>SNDRV_CTL_ELEM_IFACE_XXX</constant>. There are - <constant>MIXER</constant>, <constant>PCM</constant>, - <constant>CARD</constant>, etc. + the control, <constant>SNDRV_CTL_ELEM_IFACE_XXX</constant>, which + is usually <constant>MIXER</constant>. + Use <constant>CARD</constant> for global controls that are not + logically part of the mixer. + If the control is closely associated with some specific device on + the sound card, use <constant>HWDEP</constant>, + <constant>PCM</constant>, <constant>RAWMIDI</constant>, + <constant>TIMER</constant>, or <constant>SEQUENCER</constant>, and + specify the device number with the + <structfield>device</structfield> and + <structfield>subdevice</structfield> fields. </para> <para> diff --git a/Documentation/usb/usbmon.txt b/Documentation/usb/usbmon.txt index f1896ee3bb2..63cb7edd177 100644 --- a/Documentation/usb/usbmon.txt +++ b/Documentation/usb/usbmon.txt @@ -102,7 +102,7 @@ Here is the list of words, from left to right: - URB Status. This field makes no sense for submissions, but is present to help scripts with parsing. In error case, it contains the error code. In case of a setup packet, it contains a Setup Tag. If scripts read a number - in this field, the proceed to read Data Length. Otherwise, they read + in this field, they proceed to read Data Length. Otherwise, they read the setup packet before reading the Data Length. - Setup packet, if present, consists of 5 words: one of each for bmRequestType, bRequest, wValue, wIndex, wLength, as specified by the USB Specification 2.0. diff --git a/Documentation/video4linux/bttv/Insmod-options b/Documentation/video4linux/bttv/Insmod-options index 7bb5a50b077..fc94ff235ff 100644 --- a/Documentation/video4linux/bttv/Insmod-options +++ b/Documentation/video4linux/bttv/Insmod-options @@ -44,6 +44,9 @@ bttv.o push used by bttv. bttv will disable overlay by default on this hardware to avoid crashes. With this insmod option you can override this. + no_overlay=1 Disable overlay. It should be used by broken + hardware that doesn't support PCI2PCI direct + transfers. automute=0/1 Automatically mutes the sound if there is no TV signal, on by default. You might try to disable this if you have bad input signal diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt index 476c0c22fbb..678e8f192db 100644 --- a/Documentation/x86_64/boot-options.txt +++ b/Documentation/x86_64/boot-options.txt @@ -6,6 +6,11 @@ only the AMD64 specific ones are listed here. Machine check mce=off disable machine check + mce=bootlog Enable logging of machine checks left over from booting. + Disabled by default because some BIOS leave bogus ones. + If your BIOS doesn't do that it's a good idea to enable though + to make sure you log even machine check events that result + in a reboot. nomce (for compatibility with i386): same as mce=off |