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-rw-r--r--Documentation/cputopology.txt6
-rw-r--r--Documentation/kernel-parameters.txt7
-rw-r--r--Documentation/x86/boot.txt18
-rw-r--r--Documentation/x86/earlyprintk.txt101
4 files changed, 121 insertions, 11 deletions
diff --git a/Documentation/cputopology.txt b/Documentation/cputopology.txt
index 45932ec21cee..b41f3e58aefa 100644
--- a/Documentation/cputopology.txt
+++ b/Documentation/cputopology.txt
@@ -18,11 +18,11 @@ For an architecture to support this feature, it must define some of
these macros in include/asm-XXX/topology.h:
#define topology_physical_package_id(cpu)
#define topology_core_id(cpu)
-#define topology_thread_siblings(cpu)
-#define topology_core_siblings(cpu)
+#define topology_thread_cpumask(cpu)
+#define topology_core_cpumask(cpu)
The type of **_id is int.
-The type of siblings is cpumask_t.
+The type of siblings is (const) struct cpumask *.
To be consistent on all architectures, include/linux/topology.h
provides default definitions for any of the above macros that are
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index d1cb2069e2f4..454f42b21f16 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1320,8 +1320,13 @@ and is between 256 and 4096 characters. It is defined in the file
memtest= [KNL,X86] Enable memtest
Format: <integer>
- range: 0,4 : pattern number
default : 0 <disable>
+ Specifies the number of memtest passes to be
+ performed. Each pass selects another test
+ pattern from a given set of patterns. Memtest
+ fills the memory with this pattern, validates
+ memory contents and reserves bad memory
+ regions that are detected.
meye.*= [HW] Set MotionEye Camera parameters
See Documentation/video4linux/meye.txt.
diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt
index 7b4596ac4120..e0203662f9e9 100644
--- a/Documentation/x86/boot.txt
+++ b/Documentation/x86/boot.txt
@@ -158,7 +158,7 @@ Offset Proto Name Meaning
0202/4 2.00+ header Magic signature "HdrS"
0206/2 2.00+ version Boot protocol version supported
0208/4 2.00+ realmode_swtch Boot loader hook (see below)
-020C/2 2.00+ start_sys The load-low segment (0x1000) (obsolete)
+020C/2 2.00+ start_sys_seg The load-low segment (0x1000) (obsolete)
020E/2 2.00+ kernel_version Pointer to kernel version string
0210/1 2.00+ type_of_loader Boot loader identifier
0211/1 2.00+ loadflags Boot protocol option flags
@@ -170,10 +170,11 @@ Offset Proto Name Meaning
0224/2 2.01+ heap_end_ptr Free memory after setup end
0226/2 N/A pad1 Unused
0228/4 2.02+ cmd_line_ptr 32-bit pointer to the kernel command line
-022C/4 2.03+ initrd_addr_max Highest legal initrd address
+022C/4 2.03+ ramdisk_max Highest legal initrd address
0230/4 2.05+ kernel_alignment Physical addr alignment required for kernel
0234/1 2.05+ relocatable_kernel Whether kernel is relocatable or not
-0235/3 N/A pad2 Unused
+0235/1 N/A pad2 Unused
+0236/2 N/A pad3 Unused
0238/4 2.06+ cmdline_size Maximum size of the kernel command line
023C/4 2.07+ hardware_subarch Hardware subarchitecture
0240/8 2.07+ hardware_subarch_data Subarchitecture-specific data
@@ -299,14 +300,14 @@ Protocol: 2.00+
e.g. 0x0204 for version 2.04, and 0x0a11 for a hypothetical version
10.17.
-Field name: readmode_swtch
+Field name: realmode_swtch
Type: modify (optional)
Offset/size: 0x208/4
Protocol: 2.00+
Boot loader hook (see ADVANCED BOOT LOADER HOOKS below.)
-Field name: start_sys
+Field name: start_sys_seg
Type: read
Offset/size: 0x20c/2
Protocol: 2.00+
@@ -468,7 +469,7 @@ Protocol: 2.02+
zero, the kernel will assume that your boot loader does not support
the 2.02+ protocol.
-Field name: initrd_addr_max
+Field name: ramdisk_max
Type: read
Offset/size: 0x22c/4
Protocol: 2.03+
@@ -542,7 +543,10 @@ Protocol: 2.08+
The payload may be compressed. The format of both the compressed and
uncompressed data should be determined using the standard magic
- numbers. Currently only gzip compressed ELF is used.
+ numbers. The currently supported compression formats are gzip
+ (magic numbers 1F 8B or 1F 9E), bzip2 (magic number 42 5A) and LZMA
+ (magic number 5D 00). The uncompressed payload is currently always ELF
+ (magic number 7F 45 4C 46).
Field name: payload_length
Type: read
diff --git a/Documentation/x86/earlyprintk.txt b/Documentation/x86/earlyprintk.txt
new file mode 100644
index 000000000000..607b1a016064
--- /dev/null
+++ b/Documentation/x86/earlyprintk.txt
@@ -0,0 +1,101 @@
+
+Mini-HOWTO for using the earlyprintk=dbgp boot option with a
+USB2 Debug port key and a debug cable, on x86 systems.
+
+You need two computers, the 'USB debug key' special gadget and
+and two USB cables, connected like this:
+
+ [host/target] <-------> [USB debug key] <-------> [client/console]
+
+1. There are three specific hardware requirements:
+
+ a.) Host/target system needs to have USB debug port capability.
+
+ You can check this capability by looking at a 'Debug port' bit in
+ the lspci -vvv output:
+
+ # lspci -vvv
+ ...
+ 00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 03) (prog-if 20 [EHCI])
+ Subsystem: Lenovo ThinkPad T61
+ Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx-
+ Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
+ Latency: 0
+ Interrupt: pin D routed to IRQ 19
+ Region 0: Memory at fe227000 (32-bit, non-prefetchable) [size=1K]
+ Capabilities: [50] Power Management version 2
+ Flags: PMEClk- DSI- D1- D2- AuxCurrent=375mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
+ Status: D0 PME-Enable- DSel=0 DScale=0 PME+
+ Capabilities: [58] Debug port: BAR=1 offset=00a0
+ ^^^^^^^^^^^ <==================== [ HERE ]
+ Kernel driver in use: ehci_hcd
+ Kernel modules: ehci-hcd
+ ...
+
+( If your system does not list a debug port capability then you probably
+ wont be able to use the USB debug key. )
+
+ b.) You also need a Netchip USB debug cable/key:
+
+ http://www.plxtech.com/products/NET2000/NET20DC/default.asp
+
+ This is a small blue plastic connector with two USB connections,
+ it draws power from its USB connections.
+
+ c.) Thirdly, you need a second client/console system with a regular USB port.
+
+2. Software requirements:
+
+ a.) On the host/target system:
+
+ You need to enable the following kernel config option:
+
+ CONFIG_EARLY_PRINTK_DBGP=y
+
+ And you need to add the boot command line: "earlyprintk=dbgp".
+ (If you are using Grub, append it to the 'kernel' line in
+ /etc/grub.conf)
+
+ NOTE: normally earlyprintk console gets turned off once the
+ regular console is alive - use "earlyprintk=dbgp,keep" to keep
+ this channel open beyond early bootup. This can be useful for
+ debugging crashes under Xorg, etc.
+
+ b.) On the client/console system:
+
+ You should enable the following kernel config option:
+
+ CONFIG_USB_SERIAL_DEBUG=y
+
+ On the next bootup with the modified kernel you should
+ get a /dev/ttyUSBx device(s).
+
+ Now this channel of kernel messages is ready to be used: start
+ your favorite terminal emulator (minicom, etc.) and set
+ it up to use /dev/ttyUSB0 - or use a raw 'cat /dev/ttyUSBx' to
+ see the raw output.
+
+ c.) On Nvidia Southbridge based systems: the kernel will try to probe
+ and find out which port has debug device connected.
+
+3. Testing that it works fine:
+
+ You can test the output by using earlyprintk=dbgp,keep and provoking
+ kernel messages on the host/target system. You can provoke a harmless
+ kernel message by for example doing:
+
+ echo h > /proc/sysrq-trigger
+
+ On the host/target system you should see this help line in "dmesg" output:
+
+ SysRq : HELP : loglevel(0-9) reBoot Crashdump terminate-all-tasks(E) memory-full-oom-kill(F) kill-all-tasks(I) saK show-backtrace-all-active-cpus(L) show-memory-usage(M) nice-all-RT-tasks(N) powerOff show-registers(P) show-all-timers(Q) unRaw Sync show-task-states(T) Unmount show-blocked-tasks(W) dump-ftrace-buffer(Z)
+
+ On the client/console system do:
+
+ cat /dev/ttyUSB0
+
+ And you should see the help line above displayed shortly after you've
+ provoked it on the host system.
+
+If it does not work then please ask about it on the linux-kernel@vger.kernel.org
+mailing list or contact the x86 maintainers.