* Re: [PATCH] OMAP: Store reboot mode in scratchpad on OMAP34xx
2009-03-09 17:21 ` Tony Lindgren
@ 2009-03-09 17:50 ` Kevin Hilman
2009-03-09 18:08 ` Juha Yrjola
2009-03-12 7:57 ` Paul Walmsley
2009-08-13 12:51 ` Kevin Hilman
2 siblings, 1 reply; 8+ messages in thread
From: Kevin Hilman @ 2009-03-09 17:50 UTC (permalink / raw)
To: Tony Lindgren; +Cc: Juha Yrjola, linux-omap, Paul Walmsley
Tony Lindgren <tony@atomide.com> writes:
> * Juha Yrjola <juha.yrjola@solidboot.com> [090308 10:20]:
>> The reboot mode can be communicated to a bootloader (or the
>> kernel itself) with a scratchpad register. This functionality
>> is especially useful, if userspace is allowed to change
>> the reboot mode.
>>
>> Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
>> ---
>> arch/arm/mach-omap2/prcm.c | 10 ++++++++--
>> 1 files changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/arm/mach-omap2/prcm.c b/arch/arm/mach-omap2/prcm.c
>> index f945156..2bd239e 100644
>> --- a/arch/arm/mach-omap2/prcm.c
>> +++ b/arch/arm/mach-omap2/prcm.c
>> @@ -43,9 +43,15 @@ void omap_prcm_arch_reset(char mode)
>>
>> if (cpu_is_omap24xx())
>> prcm_offs = WKUP_MOD;
>> - else if (cpu_is_omap34xx())
>> + else if (cpu_is_omap34xx()) {
>> + u32 l;
>> +
>> prcm_offs = OMAP3430_GR_MOD;
>> - else
>> + l = ('B' << 24) | ('M' << 16) | mode;
>> + /* Reserve the first word in scratchpad for communicating
>> + * with the boot ROM. */
>> + omap_writel(l, OMAP343X_SCRATCHPAD + 4);
>> + } else
>> WARN_ON(1);
>>
>> prm_set_mod_reg_bits(OMAP_RST_DPLL3, prcm_offs, RM_RSTCTRL);
>
> Looks OK to me, any comments from Kevin or Paul?
>
Looks ok to me.
Maybe just a brief description of this scratchpad location is reserved.
Is there a boot ROM doc that could be referenced?
Any interactions with bootrom are a bit of black magic, so I like there to be
as much description as possible.
Kevin
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] OMAP: Store reboot mode in scratchpad on OMAP34xx
2009-03-09 17:50 ` Kevin Hilman
@ 2009-03-09 18:08 ` Juha Yrjola
2009-03-09 18:25 ` Kevin Hilman
0 siblings, 1 reply; 8+ messages in thread
From: Juha Yrjola @ 2009-03-09 18:08 UTC (permalink / raw)
To: Kevin Hilman; +Cc: Tony Lindgren, linux-omap, Paul Walmsley
Kevin Hilman wrote:
> Maybe just a brief description of this scratchpad location is reserved.
> Is there a boot ROM doc that could be referenced?
I don't know how public the boot ROM behaviour is. On my OMAP34xx TRM,
the relevant info is in Chapter 26.4.4.4, Software Booting Configuration.
Cheers,
Juha
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] OMAP: Store reboot mode in scratchpad on OMAP34xx
2009-03-09 18:08 ` Juha Yrjola
@ 2009-03-09 18:25 ` Kevin Hilman
0 siblings, 0 replies; 8+ messages in thread
From: Kevin Hilman @ 2009-03-09 18:25 UTC (permalink / raw)
To: Juha Yrjola; +Cc: Tony Lindgren, linux-omap, Paul Walmsley
Juha Yrjola <juha.yrjola@solidboot.com> writes:
> Kevin Hilman wrote:
>
>> Maybe just a brief description of this scratchpad location is reserved.
>> Is there a boot ROM doc that could be referenced?
>
> I don't know how public the boot ROM behaviour is. On my OMAP34xx TRM,
> the relevant info is in Chapter 26.4.4.4, Software Booting
> Configuration.
I think we can reference the TRM section without describing it and
that should be safe under the NDAs.
Kevin
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] OMAP: Store reboot mode in scratchpad on OMAP34xx
2009-03-09 17:21 ` Tony Lindgren
2009-03-09 17:50 ` Kevin Hilman
@ 2009-03-12 7:57 ` Paul Walmsley
2009-08-13 12:51 ` Kevin Hilman
2 siblings, 0 replies; 8+ messages in thread
From: Paul Walmsley @ 2009-03-12 7:57 UTC (permalink / raw)
To: Tony Lindgren; +Cc: Juha Yrjola, linux-omap, Kevin Hilman
On Mon, 9 Mar 2009, Tony Lindgren wrote:
> * Juha Yrjola <juha.yrjola@solidboot.com> [090308 10:20]:
> > The reboot mode can be communicated to a bootloader (or the
> > kernel itself) with a scratchpad register. This functionality
> > is especially useful, if userspace is allowed to change
> > the reboot mode.
> >
> > Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
> > ---
> > arch/arm/mach-omap2/prcm.c | 10 ++++++++--
> > 1 files changed, 8 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/arm/mach-omap2/prcm.c b/arch/arm/mach-omap2/prcm.c
> > index f945156..2bd239e 100644
> > --- a/arch/arm/mach-omap2/prcm.c
> > +++ b/arch/arm/mach-omap2/prcm.c
> > @@ -43,9 +43,15 @@ void omap_prcm_arch_reset(char mode)
> >
> > if (cpu_is_omap24xx())
> > prcm_offs = WKUP_MOD;
> > - else if (cpu_is_omap34xx())
> > + else if (cpu_is_omap34xx()) {
> > + u32 l;
> > +
> > prcm_offs = OMAP3430_GR_MOD;
> > - else
> > + l = ('B' << 24) | ('M' << 16) | mode;
> > + /* Reserve the first word in scratchpad for communicating
> > + * with the boot ROM. */
> > + omap_writel(l, OMAP343X_SCRATCHPAD + 4);
> > + } else
> > WARN_ON(1);
> >
> > prm_set_mod_reg_bits(OMAP_RST_DPLL3, prcm_offs, RM_RSTCTRL);
>
> Looks OK to me, any comments from Kevin or Paul?
Can't find "BMxx" in the Rev O 34xx TRM. Is this a NOLO-specific feature,
or is this a known standard supported by other bootloaders? If the
former, maybe it would be good to add a few lines of documentation in
Documentation/arm/OMAP/rebooting or some other place?
- Paul
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] OMAP: Store reboot mode in scratchpad on OMAP34xx
2009-03-09 17:21 ` Tony Lindgren
2009-03-09 17:50 ` Kevin Hilman
2009-03-12 7:57 ` Paul Walmsley
@ 2009-08-13 12:51 ` Kevin Hilman
2009-08-13 12:54 ` Paul Walmsley
2 siblings, 1 reply; 8+ messages in thread
From: Kevin Hilman @ 2009-08-13 12:51 UTC (permalink / raw)
To: Tony Lindgren; +Cc: Juha Yrjola, linux-omap, Paul Walmsley
Tony Lindgren <tony@atomide.com> writes:
> * Juha Yrjola <juha.yrjola@solidboot.com> [090308 10:20]:
>> The reboot mode can be communicated to a bootloader (or the
>> kernel itself) with a scratchpad register. This functionality
>> is especially useful, if userspace is allowed to change
>> the reboot mode.
>>
>> Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
>> ---
>> arch/arm/mach-omap2/prcm.c | 10 ++++++++--
>> 1 files changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/arm/mach-omap2/prcm.c b/arch/arm/mach-omap2/prcm.c
>> index f945156..2bd239e 100644
>> --- a/arch/arm/mach-omap2/prcm.c
>> +++ b/arch/arm/mach-omap2/prcm.c
>> @@ -43,9 +43,15 @@ void omap_prcm_arch_reset(char mode)
>>
>> if (cpu_is_omap24xx())
>> prcm_offs = WKUP_MOD;
>> - else if (cpu_is_omap34xx())
>> + else if (cpu_is_omap34xx()) {
>> + u32 l;
>> +
>> prcm_offs = OMAP3430_GR_MOD;
>> - else
>> + l = ('B' << 24) | ('M' << 16) | mode;
>> + /* Reserve the first word in scratchpad for communicating
>> + * with the boot ROM. */
>> + omap_writel(l, OMAP343X_SCRATCHPAD + 4);
>> + } else
>> WARN_ON(1);
>>
>> prm_set_mod_reg_bits(OMAP_RST_DPLL3, prcm_offs, RM_RSTCTRL);
>
> Looks OK to me, any comments from Kevin or Paul?
>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
I've had this one in the PM branch for awhile now I think can go upstream.
Kevin
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] OMAP: Store reboot mode in scratchpad on OMAP34xx
2009-08-13 12:51 ` Kevin Hilman
@ 2009-08-13 12:54 ` Paul Walmsley
0 siblings, 0 replies; 8+ messages in thread
From: Paul Walmsley @ 2009-08-13 12:54 UTC (permalink / raw)
To: Kevin Hilman; +Cc: Tony Lindgren, Juha Yrjola, linux-omap
On Thu, 13 Aug 2009, Kevin Hilman wrote:
> Tony Lindgren <tony@atomide.com> writes:
>
> > * Juha Yrjola <juha.yrjola@solidboot.com> [090308 10:20]:
> >> The reboot mode can be communicated to a bootloader (or the
> >> kernel itself) with a scratchpad register. This functionality
> >> is especially useful, if userspace is allowed to change
> >> the reboot mode.
> >>
> >> Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
> >> ---
> >> arch/arm/mach-omap2/prcm.c | 10 ++++++++--
> >> 1 files changed, 8 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/arch/arm/mach-omap2/prcm.c b/arch/arm/mach-omap2/prcm.c
> >> index f945156..2bd239e 100644
> >> --- a/arch/arm/mach-omap2/prcm.c
> >> +++ b/arch/arm/mach-omap2/prcm.c
> >> @@ -43,9 +43,15 @@ void omap_prcm_arch_reset(char mode)
> >>
> >> if (cpu_is_omap24xx())
> >> prcm_offs = WKUP_MOD;
> >> - else if (cpu_is_omap34xx())
> >> + else if (cpu_is_omap34xx()) {
> >> + u32 l;
> >> +
> >> prcm_offs = OMAP3430_GR_MOD;
> >> - else
> >> + l = ('B' << 24) | ('M' << 16) | mode;
> >> + /* Reserve the first word in scratchpad for communicating
> >> + * with the boot ROM. */
> >> + omap_writel(l, OMAP343X_SCRATCHPAD + 4);
> >> + } else
> >> WARN_ON(1);
> >>
> >> prm_set_mod_reg_bits(OMAP_RST_DPLL3, prcm_offs, RM_RSTCTRL);
> >
> > Looks OK to me, any comments from Kevin or Paul?
> >
>
> Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
>
> I've had this one in the PM branch for awhile now I think can go upstream.
The omap_writel() should be nuked and replaced that with an
omap_ctrl_write(). Other than that, I don't have any comment on it...
- Paul
^ permalink raw reply [flat|nested] 8+ messages in thread