Merge branch 'next' into for-linus

[firefly-linux-kernel-4.4.55.git] / Documentation / debugging-via-ohci1394.txt

diff --git a/Documentation/debugging-via-ohci1394.txt b/Documentation/debugging-via-ohci1394.txt
index 611f5a5499b153c9594ad37e7237f7a35489b3bd..fa0151a712f9c5a0d9fe43db6e0746ff4046a5e0 100644 (file)
--- a/Documentation/debugging-via-ohci1394.txt
+++ b/Documentation/debugging-via-ohci1394.txt
@@ -22,10 +22,12 @@ locations such as buffers like the printk buffer or the process table.
 Retrieving a full system memory dump is also possible over the FireWire,
 using data transfer rates in the order of 10MB/s or more.
 
 Retrieving a full system memory dump is also possible over the FireWire,
 using data transfer rates in the order of 10MB/s or more.
 

-Memory access is currently limited to the low 4G of physical address
-space which can be a problem on IA64 machines where memory is located
-mostly above that limit, but it is rarely a problem on more common
-hardware such as hardware based on x86, x86-64 and PowerPC.
+With most FireWire controllers, memory access is limited to the low 4 GB
+of physical address space.  This can be a problem on IA64 machines where
+memory is located mostly above that limit, but it is rarely a problem on
+more common hardware such as x86, x86-64 and PowerPC.  However, at least
+Agere/LSI FW643e and FW643e2 controllers are known to support access to
+physical addresses above 4 GB.

 
 Together with a early initialization of the OHCI-1394 controller for debugging,
 this facility proved most useful for examining long debugs logs in the printk
 
 Together with a early initialization of the OHCI-1394 controller for debugging,
 this facility proved most useful for examining long debugs logs in the printk


@@ -36,17 +38,11 @@ available (notebooks) or too slow for extensive debug information (like ACPI).
 Drivers
 -------
 
 Drivers
 -------
 

-The ohci1394 driver in drivers/ieee1394 initializes the OHCI-1394 controllers
-to a working state and enables physical DMA by default for all remote nodes.
-This can be turned off by ohci1394's module parameter phys_dma=0.
-
-The alternative firewire-ohci driver in drivers/firewire uses filtered physical
+The firewire-ohci driver in drivers/firewire uses filtered physical

 DMA by default, which is more secure but not suitable for remote debugging.
 DMA by default, which is more secure but not suitable for remote debugging.

-Compile the driver with CONFIG_FIREWIRE_OHCI_REMOTE_DMA (Kernel hacking menu:
-Remote debugging over FireWire with firewire-ohci) to get unfiltered physical
-DMA.
+Pass the remote_dma=1 parameter to the driver to get unfiltered physical DMA.

 
 

-Because ohci1394 and firewire-ohci depend on the PCI enumeration to be
+Because the firewire-ohci driver depends on the PCI enumeration to be

 completed, an initialization routine which runs pretty early has been
 implemented for x86.  This routine runs long before console_init() can be
 called, i.e. before the printk buffer appears on the console.
 completed, an initialization routine which runs pretty early has been
 implemented for x86.  This routine runs long before console_init() can be
 called, i.e. before the printk buffer appears on the console.


@@ -64,7 +60,7 @@ be used to view the printk buffer of a remote machine, even with live update.
 
 Bernhard Kaindl enhanced firescope to support accessing 64-bit machines
 from 32-bit firescope and vice versa:
 
 Bernhard Kaindl enhanced firescope to support accessing 64-bit machines
 from 32-bit firescope and vice versa:

-- http://halobates.de/firewire/firescope-0.2.2.tar.bz2
+- http://v3.sk/~lkundrak/firescope/

 
 and he implemented fast system dump (alpha version - read README.txt):
 - http://halobates.de/firewire/firedump-0.1.tar.bz2
 
 and he implemented fast system dump (alpha version - read README.txt):
 - http://halobates.de/firewire/firedump-0.1.tar.bz2


@@ -92,11 +88,11 @@ Step-by-step instructions for using firescope with early OHCI initialization:
 
 1) Verify that your hardware is supported:
 
 
 1) Verify that your hardware is supported:
 

-   Load the ohci1394 or the fw-ohci module and check your kernel logs.
+   Load the firewire-ohci module and check your kernel logs.

    You should see a line similar to
 
    You should see a line similar to
 

-   ohci1394: fw-host0: OHCI-1394 1.1 (PCI): IRQ=[18]  MMIO=[fe9ff800-fe9fffff]
-   ... Max Packet=[2048]  IR/IT contexts=[4/8]
+   firewire_ohci 0000:15:00.1: added OHCI v1.0 device as card 2, 4 IR + 4 IT
+   ... contexts, quirks 0x11

 
    when loading the driver. If you have no supported controller, many PCI,
    CardBus and even some Express cards which are fully compliant to OHCI-1394
 
    when loading the driver. If you have no supported controller, many PCI,
    CardBus and even some Express cards which are fully compliant to OHCI-1394


@@ -105,6 +101,9 @@ Step-by-step instructions for using firescope with early OHCI initialization:
    compliant, they are based on TI PCILynx chips and require drivers for Win-
    dows operating systems.
 
    compliant, they are based on TI PCILynx chips and require drivers for Win-
    dows operating systems.
 

+   The mentioned kernel log message contains ">4 GB phys DMA" in case of
+   OHCI-1394 controllers which support accesses above this limit.
+

 2) Establish a working FireWire cable connection:
 
    Any FireWire cable, as long at it provides electrically and mechanically
 2) Establish a working FireWire cable connection:
 
    Any FireWire cable, as long at it provides electrically and mechanically


@@ -113,20 +112,18 @@ Step-by-step instructions for using firescope with early OHCI initialization:
 
    If an driver is running on both machines you should see a line like
 
 
    If an driver is running on both machines you should see a line like
 

-   ieee1394: Node added: ID:BUS[0-01:1023]  GUID[0090270001b84bba]
+   firewire_core 0000:15:00.1: created device fw1: GUID 00061b0020105917, S400

 
    on both machines in the kernel log when the cable is plugged in
    and connects the two machines.
 
 3) Test physical DMA using firescope:
 
 
    on both machines in the kernel log when the cable is plugged in
    and connects the two machines.
 
 3) Test physical DMA using firescope:
 

-   On the debug host,
-       - load the raw1394 module,
-       - make sure that /dev/raw1394 is accessible,
+   On the debug host, make sure that /dev/fw* is accessible,

    then start firescope:
 
        $ firescope
    then start firescope:
 
        $ firescope

-       Port 0 (ohci1394) opened, 2 nodes detected
+       Port 0 (/dev/fw1) opened, 2 nodes detected

 
        FireScope
        ---------
 
        FireScope
        ---------