diff mbox

ARM: tegra: add kexec support to defconfig

Message ID 1357161141-26430-1-git-send-email-swarren@wwwdotorg.org (mailing list archive)
State New, archived
Headers show

Commit Message

Stephen Warren Jan. 2, 2013, 9:12 p.m. UTC 
From: Stephen Warren <swarren@nvidia.com>

Signed-off-by: Stephen Warren <swarren@nvidia.com>
---
 arch/arm/configs/tegra_defconfig |    1 +
 1 file changed, 1 insertion(+)

Comments

Stephen Warren Jan. 3, 2013, 4:50 p.m. UTC | #1 
On 01/02/2013 02:12 PM, Stephen Warren wrote:
>...

Applied to (squashed into) Tegra's for-3.9/defconfig branch.
Thierry Reding Jan. 3, 2013, 9:05 p.m. UTC | #2 
On Wed, Jan 02, 2013 at 02:12:21PM -0700, Stephen Warren wrote:
> From: Stephen Warren <swarren@nvidia.com>
> 
> Signed-off-by: Stephen Warren <swarren@nvidia.com>
> ---
>  arch/arm/configs/tegra_defconfig |    1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm/configs/tegra_defconfig b/arch/arm/configs/tegra_defconfig
> index 742dc41..e621603 100644
> --- a/arch/arm/configs/tegra_defconfig
> +++ b/arch/arm/configs/tegra_defconfig
> @@ -34,6 +34,7 @@ CONFIG_AEABI=y
>  CONFIG_HIGHMEM=y
>  CONFIG_ZBOOT_ROM_TEXT=0x0
>  CONFIG_ZBOOT_ROM_BSS=0x0
> +CONFIG_KEXEC=y
>  CONFIG_CPU_FREQ=y
>  CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
>  CONFIG_CPU_IDLE=y

Interesting. What do you plan to use this for? kdump?

Thierry
Stephen Warren Jan. 3, 2013, 9:18 p.m. UTC | #3 
On 01/03/2013 02:05 PM, Thierry Reding wrote:
> On Wed, Jan 02, 2013 at 02:12:21PM -0700, Stephen Warren wrote:
>> From: Stephen Warren <swarren@nvidia.com>
>> 
>> Signed-off-by: Stephen Warren <swarren@nvidia.com> --- 
>> arch/arm/configs/tegra_defconfig |    1 + 1 file changed, 1
>> insertion(+)
>> 
>> diff --git a/arch/arm/configs/tegra_defconfig
>> b/arch/arm/configs/tegra_defconfig index 742dc41..e621603 100644 
>> --- a/arch/arm/configs/tegra_defconfig +++
>> b/arch/arm/configs/tegra_defconfig @@ -34,6 +34,7 @@
>> CONFIG_AEABI=y CONFIG_HIGHMEM=y CONFIG_ZBOOT_ROM_TEXT=0x0 
>> CONFIG_ZBOOT_ROM_BSS=0x0 +CONFIG_KEXEC=y CONFIG_CPU_FREQ=y 
>> CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y CONFIG_CPU_IDLE=y
> 
> Interesting. What do you plan to use this for? kdump?

I plan to burn a kernel (and a small stub, and a DTB) into flash
instead of U-Boot, and hence not have to rely on any bootloader.

Even ignoring that, a quick scp of a new kernel to a target followed
by a kexec is faster than rebooting all the way through U-Boot's
slower Ethernet support to boot a new kernel.
Thierry Reding Jan. 3, 2013, 9:29 p.m. UTC | #4 
On Thu, Jan 03, 2013 at 02:18:27PM -0700, Stephen Warren wrote:
> On 01/03/2013 02:05 PM, Thierry Reding wrote:
> > On Wed, Jan 02, 2013 at 02:12:21PM -0700, Stephen Warren wrote:
> >> From: Stephen Warren <swarren@nvidia.com>
> >> 
> >> Signed-off-by: Stephen Warren <swarren@nvidia.com> --- 
> >> arch/arm/configs/tegra_defconfig |    1 + 1 file changed, 1
> >> insertion(+)
> >> 
> >> diff --git a/arch/arm/configs/tegra_defconfig
> >> b/arch/arm/configs/tegra_defconfig index 742dc41..e621603 100644 
> >> --- a/arch/arm/configs/tegra_defconfig +++
> >> b/arch/arm/configs/tegra_defconfig @@ -34,6 +34,7 @@
> >> CONFIG_AEABI=y CONFIG_HIGHMEM=y CONFIG_ZBOOT_ROM_TEXT=0x0 
> >> CONFIG_ZBOOT_ROM_BSS=0x0 +CONFIG_KEXEC=y CONFIG_CPU_FREQ=y 
> >> CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y CONFIG_CPU_IDLE=y
> > 
> > Interesting. What do you plan to use this for? kdump?
> 
> I plan to burn a kernel (and a small stub, and a DTB) into flash
> instead of U-Boot, and hence not have to rely on any bootloader.

Why does that require kexec support?

> Even ignoring that, a quick scp of a new kernel to a target followed
> by a kexec is faster than rebooting all the way through U-Boot's
> slower Ethernet support to boot a new kernel.

That sounds like an interesting approach. I wonder if this actually
works with the current state of drivers in mainline. Sounds like this
could speed up development quite a bit by avoiding full reboots.

Thierry
Stephen Warren Jan. 3, 2013, 9:45 p.m. UTC | #5 
On 01/03/2013 02:29 PM, Thierry Reding wrote:
> On Thu, Jan 03, 2013 at 02:18:27PM -0700, Stephen Warren wrote:
>> On 01/03/2013 02:05 PM, Thierry Reding wrote:
>>> On Wed, Jan 02, 2013 at 02:12:21PM -0700, Stephen Warren
>>> wrote:
>>>> From: Stephen Warren <swarren@nvidia.com>
>>>> 
>>>> Signed-off-by: Stephen Warren <swarren@nvidia.com> --- 
>>>> arch/arm/configs/tegra_defconfig |    1 + 1 file changed, 1 
>>>> insertion(+)
>>>> 
>>>> diff --git a/arch/arm/configs/tegra_defconfig 
>>>> b/arch/arm/configs/tegra_defconfig index 742dc41..e621603
>>>> 100644 --- a/arch/arm/configs/tegra_defconfig +++ 
>>>> b/arch/arm/configs/tegra_defconfig @@ -34,6 +34,7 @@ 
>>>> CONFIG_AEABI=y CONFIG_HIGHMEM=y CONFIG_ZBOOT_ROM_TEXT=0x0 
>>>> CONFIG_ZBOOT_ROM_BSS=0x0 +CONFIG_KEXEC=y CONFIG_CPU_FREQ=y 
>>>> CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y CONFIG_CPU_IDLE=y
>>> 
>>> Interesting. What do you plan to use this for? kdump?
>> 
>> I plan to burn a kernel (and a small stub, and a DTB) into flash 
>> instead of U-Boot, and hence not have to rely on any bootloader.
> 
> Why does that require kexec support?

Because I'd be using that kernel plus an initrd to download the "real"
kernel over e.g. TFTP and kexec it.
Thierry Reding Jan. 4, 2013, 8:08 p.m. UTC | #6 
On Thu, Jan 03, 2013 at 02:45:02PM -0700, Stephen Warren wrote:
> On 01/03/2013 02:29 PM, Thierry Reding wrote:
> > On Thu, Jan 03, 2013 at 02:18:27PM -0700, Stephen Warren wrote:
> >> On 01/03/2013 02:05 PM, Thierry Reding wrote:
> >>> On Wed, Jan 02, 2013 at 02:12:21PM -0700, Stephen Warren
> >>> wrote:
> >>>> From: Stephen Warren <swarren@nvidia.com>
> >>>> 
> >>>> Signed-off-by: Stephen Warren <swarren@nvidia.com> --- 
> >>>> arch/arm/configs/tegra_defconfig |    1 + 1 file changed, 1 
> >>>> insertion(+)
> >>>> 
> >>>> diff --git a/arch/arm/configs/tegra_defconfig 
> >>>> b/arch/arm/configs/tegra_defconfig index 742dc41..e621603
> >>>> 100644 --- a/arch/arm/configs/tegra_defconfig +++ 
> >>>> b/arch/arm/configs/tegra_defconfig @@ -34,6 +34,7 @@ 
> >>>> CONFIG_AEABI=y CONFIG_HIGHMEM=y CONFIG_ZBOOT_ROM_TEXT=0x0 
> >>>> CONFIG_ZBOOT_ROM_BSS=0x0 +CONFIG_KEXEC=y CONFIG_CPU_FREQ=y 
> >>>> CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y CONFIG_CPU_IDLE=y
> >>> 
> >>> Interesting. What do you plan to use this for? kdump?
> >> 
> >> I plan to burn a kernel (and a small stub, and a DTB) into flash 
> >> instead of U-Boot, and hence not have to rely on any bootloader.
> > 
> > Why does that require kexec support?
> 
> Because I'd be using that kernel plus an initrd to download the "real"
> kernel over e.g. TFTP and kexec it.

Right, that makes sense. Thanks for explaining.

Thierry
diff mbox

Patch

diff --git a/arch/arm/configs/tegra_defconfig b/arch/arm/configs/tegra_defconfig
index 742dc41..e621603 100644
--- a/arch/arm/configs/tegra_defconfig
+++ b/arch/arm/configs/tegra_defconfig
@@ -34,6 +34,7 @@  CONFIG_AEABI=y
 CONFIG_HIGHMEM=y
 CONFIG_ZBOOT_ROM_TEXT=0x0
 CONFIG_ZBOOT_ROM_BSS=0x0
+CONFIG_KEXEC=y
 CONFIG_CPU_FREQ=y
 CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
 CONFIG_CPU_IDLE=y