* Re: [PATCH v20 14/14] Documentation: dt: usable-memory and elfcorehdr nodes for arm64 kexec [not found] ` <e212cd53fdf9d09923408eb906fe0228d22432a9.1466702804.git.geoff@infradead.org> @ 2016-06-27 18:22 ` Thiago Jung Bauermann 2016-06-28 3:59 ` Michael Ellerman 0 siblings, 1 reply; 2+ messages in thread From: Thiago Jung Bauermann @ 2016-06-27 18:22 UTC (permalink / raw) To: Geoff Levand, James Morse, kexec, linuxppc-dev Hello, Am Donnerstag, 23 Juni 2016, 17:54:49 schrieb Geoff Levand: > +linux,usable-memory > +------------------- > + > +This property is set on PowerPC and arm64 by kexec-tools during kdump > +to tell the crash kernel the base address of its reserved area of memory, > and +the size. e.g. > + > +/ { > + chosen { > + linux,usable-memory = <0x9 0xf0000000 0x0 0x10000000>; > + }; > +}; On powerpc, linux,usable-memory isn't in /chosen. It is put by kexec-tools in each /memory node and has the same format as the reg property. During early boot, the kernel goes through the /memory nodes to find usable memory and for each node, if there's a linux,usable-memory property it will use it instead of the reg property to find the ranges of memory it can use (see early_init_dt_scan_memory in drivers/of/fdt.c). []'s Thiago Jung Bauermann IBM Linux Technology Center ^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: [PATCH v20 14/14] Documentation: dt: usable-memory and elfcorehdr nodes for arm64 kexec 2016-06-27 18:22 ` [PATCH v20 14/14] Documentation: dt: usable-memory and elfcorehdr nodes for arm64 kexec Thiago Jung Bauermann @ 2016-06-28 3:59 ` Michael Ellerman 0 siblings, 0 replies; 2+ messages in thread From: Michael Ellerman @ 2016-06-28 3:59 UTC (permalink / raw) To: Thiago Jung Bauermann, Geoff Levand, James Morse, kexec, linuxppc-dev On Mon, 2016-06-27 at 15:22 -0300, Thiago Jung Bauermann wrote: > Am Donnerstag, 23 Juni 2016, 17:54:49 schrieb Geoff Levand: > > +linux,usable-memory > > +------------------- > > + > > +This property is set on PowerPC and arm64 by kexec-tools during kdump > > +to tell the crash kernel the base address of its reserved area of memory, > > and +the size. e.g. > > + > > +/ { > > + chosen { > > + linux,usable-memory = <0x9 0xf0000000 0x0 0x10000000>; > > + }; > > +}; > > On powerpc, linux,usable-memory isn't in /chosen. It is put by kexec-tools > in each /memory node and has the same format as the reg property. During > early boot, the kernel goes through the /memory nodes to find usable memory > and for each node, if there's a linux,usable-memory property it will use it > instead of the reg property to find the ranges of memory it can use (see > early_init_dt_scan_memory in drivers/of/fdt.c). Yep that sounds right to me. Added in: ba7594852f4e ("[PATCH] powerpc: Add support for "linux,usable-memory" on memory nodes") cheers ^ permalink raw reply [flat|nested] 2+ messages in thread
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2016-06-27 18:22 ` [PATCH v20 14/14] Documentation: dt: usable-memory and elfcorehdr nodes for arm64 kexec Thiago Jung Bauermann
2016-06-28 3:59 ` Michael Ellerman
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