| Message ID | alpine.DEB.2.21.9999.1910091252160.11044@viisi.sifive.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Documentation: admin-guide: add earlycon documentation for RISC-V | expand |
On Wed, Oct 9, 2019 at 9:53 PM Paul Walmsley <paul.walmsley@sifive.com> wrote: > Kernels booting on RISC-V can specify "earlycon" with no options on > the Linux command line, and the generic DT earlycon support will query > the "chosen/stdout-path" property (if present) to determine which > early console device to use. Document this appropriately in the > admin-guide. > > Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Gr{oetje,eeting}s, Geert
On Thu, 10 Oct 2019 09:10:18 +0200 Geert Uytterhoeven <geert@linux-m68k.org> wrote: > On Wed, Oct 9, 2019 at 9:53 PM Paul Walmsley <paul.walmsley@sifive.com> wrote: > > Kernels booting on RISC-V can specify "earlycon" with no options on > > the Linux command line, and the generic DT earlycon support will query > > the "chosen/stdout-path" property (if present) to determine which > > early console device to use. Document this appropriately in the > > admin-guide. > > > > Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> > > Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Applied, thanks. jon
On Wed, Oct 09, 2019 at 12:53:50PM -0700, Paul Walmsley wrote: > > Kernels booting on RISC-V can specify "earlycon" with no options on > the Linux command line, and the generic DT earlycon support will query > the "chosen/stdout-path" property (if present) to determine which > early console device to use. Document this appropriately in the > admin-guide. Jon already applied a patch from me removing the bogus arch restrictions on the earlycon without arguments documentation, so this should not be required.
Jon, can you please revert this? The paragraph above this addition already describes the riscv case perfecty well with my previous patch: earlycon= [KNL] Output early console device and options. When used with no options, the early console is determined by stdout-path property in device tree's chosen node or the ACPI SPCR table if supported by the platform. [RISCV] When used with no options, the early console is determined by the stdout-path property in the device tree's chosen node.
Hi Jon, On Fri, 8 Nov 2019, Christoph Hellwig wrote: > can you please revert this? The paragraph above this addition already > describes the riscv case perfecty well with my previous patch: > > earlycon= [KNL] Output early console device and options. > > When used with no options, the early console is > determined by stdout-path property in device tree's > chosen node or the ACPI SPCR table if supported by > the platform. > > [RISCV] When used with no options, the early > console is determined by the stdout-path > property in the device tree's chosen node. I support reverting the RISCV section, now that Christoph's more general change has gone in. - Paul
On Mon, 11 Nov 2019 17:30:13 +0000 (UTC) Paul Walmsley <paul@pwsan.com> wrote: > On Fri, 8 Nov 2019, Christoph Hellwig wrote: > > > can you please revert this? The paragraph above this addition already > > describes the riscv case perfecty well with my previous patch: > > > > earlycon= [KNL] Output early console device and options. > > > > When used with no options, the early console is > > determined by stdout-path property in device tree's > > chosen node or the ACPI SPCR table if supported by > > the platform. > > > > [RISCV] When used with no options, the early > > console is determined by the stdout-path > > property in the device tree's chosen node. > > I support reverting the RISCV section, now that Christoph's more general > change has gone in. OK, the patch has been reverted. Thanks, jon
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index c7ac2f3ac99f..011fee969ece 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -990,6 +990,10 @@ [X86] When used with no options the early console is determined by the ACPI SPCR table. + [RISCV] When used with no options, the early + console is determined by the stdout-path + property in the device tree's chosen node. + cdns,<addr>[,options] Start an early, polled-mode console on a Cadence (xuartps) serial port at the specified address. Only
Kernels booting on RISC-V can specify "earlycon" with no options on the Linux command line, and the generic DT earlycon support will query the "chosen/stdout-path" property (if present) to determine which early console device to use. Document this appropriately in the admin-guide. Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Andreas Schwab <schwab@suse.de> --- Documentation/admin-guide/kernel-parameters.txt | 4 ++++ 1 file changed, 4 insertions(+)