On 2019-01-31 00:07, Rob Herring wrote:> On Wed, Jan 23, 2019 at 08:05:13PM +0800, liaoweixiong wrote: >> Create DT binding document for blkoops. >> >> Signed-off-by: liaoweixiong <liaoweixiong@xxxxxxxxxxxxxxxxx> >> --- >> .../devicetree/bindings/pstore-block/blkoops.txt | 32 ++++++++++++++++++++++ > > /bindings/pstore/... > > I wouldn't call it blkoops either. I believe ramoops is called that to > maintain compatibility keeping the same kernel module name that > preceeded pstore. > Fixed. In addition, I don't known whether should we move ramreserved-memory/ooos.txt to /bindings/pstore. This is for maintainer to decide, and do it on other patch. >> MAINTAINERS | 1 + >> 2 files changed, 33 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/pstore-block/blkoops.txt >> >> diff --git a/Documentation/devicetree/bindings/pstore-block/blkoops.txt b/Documentation/devicetree/bindings/pstore-block/blkoops.txt >> new file mode 100644 >> index 0000000..a25835b >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/pstore-block/blkoops.txt >> @@ -0,0 +1,32 @@ >> +Blkoops oops logger >> +=================== >> + >> +Blkoops provides a block partition for oops, excluding panics now, so they can >> +be recovered after a reboot. >> + >> +Any space of block partition will be used for a circular buffer of oops records. >> +These records have a configurable size, with a size of 0 indicating that they >> +should be disabled. >> + >> +"partition-size" and at least one of "dmesg-size" or "pmsg-size" must be set >> +non-zero, but are otherwise optional as listed below. >> + >> +Blkoops will take value from Kconfig if device tree do not set, but settings >> +from module parameters can also overwrite them. > > That's all kernel details not relevant to the binidng. > Deleted. >> + >> +Required properties: >> + >> +- compatible: must be "blkoops". >> + >> +- partition-size: size in kbytes, must be a multiple of 4. > > This seems unnecessary given a partition has a known size. > partition-size is necessary for psotre/blk. User should tell pstore/blk how large space can it use. >> + >> +Optional properties: >> + >> +- partition-path: strings must begin with "/dev", tell blkoops which partition >> + it can used. If it is not set, blkoops will drop all data when reboot. > > No. '/dev/...' is a Linux thing and doesn't belong in DT. > > You should define a partition UUID and/or label and the kernel can find > the right partition to use. > pstore/blk do general read/write by filp_open/kernel_read/kernel_write, which need device path. In addition, i have no idea how to use UUID and/or label to do general read/write on kernel layer, can you give me a tip? >> + >> +- dmesg-size: maximum size in kbytes of each dump done on oops, which must be a >> + multiple of 4. >> + >> +- pmsg-size: maximum size in kbytes for userspace messages, which must be a >> + multiple of 4. > > Common properties shared with ramoops should be in a common doc. > The size limit are different. Size for ramoops must be power of 2, but be a multiple of 4k for pstore/blk. > Rob > -- liaoweixiong
