[PATCH v5 2/2] powerpc/fadump: update documentation about 'fadump_append=' parameter

[Hari Bathini <hbathini@linux.vnet.ibm.com>]

With the introduction of 'fadump_append=' parameter to pass additional
parameters to fadump (capture) kernel, update documentation about it.

Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
---

Changes from v4:
* Based on top of patchset that includes
  https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?h=akpm&id=05f383cdfba8793240e73f9a9fbff4e25d66003f


 Documentation/powerpc/firmware-assisted-dump.txt |   10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/Documentation/powerpc/firmware-assisted-dump.txt b/Documentation/powerpc/firmware-assisted-dump.txt
index 8394bc8..6327193 100644
--- a/Documentation/powerpc/firmware-assisted-dump.txt
+++ b/Documentation/powerpc/firmware-assisted-dump.txt
@@ -162,7 +162,15 @@ How to enable firmware-assisted dump (fadump):
 
 1. Set config option CONFIG_FA_DUMP=y and build kernel.
 2. Boot into linux kernel with 'fadump=on' kernel cmdline option.
-3. Optionally, user can also set 'crashkernel=' kernel cmdline
+3. A user can pass additional command line parameters as a comma
+   separated list through 'fadump_append=' parameter, to be enforced
+   when fadump is active. For example, if parameters like nr_cpus=1,
+   numa=off & udev.children-max=2 are to be enforced when fadump is
+   active, 'fadump_append=nr_cpus=1,numa=off,udev.children-max=2'
+   can be passed in command line, which will be replaced with
+   "nr_cpus=1 numa=off udev.children-max=2" when fadump is active.
+   This helps in reducing memory consumption during dump capture.
+4. Optionally, user can also set 'crashkernel=' kernel cmdline
    to specify size of the memory to reserve for boot memory dump
    preservation.