This patch keeps disabled the strict alignment CP15 bit for
all armv6 and armv7 processor without the mmu. This behaviour
is now same as in the mmu case.
Signed-off-by: Armando Visconti <redacted>
---
arch/arm/kernel/head-nommu.S | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
This patch keeps disabled the strict alignment CP15 bit for
all armv6 and armv7 processor without the mmu. This behaviour
is now same as in the mmu case.
Signed-off-by: Armando Visconti<redacted>
---
arch/arm/kernel/head-nommu.S | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
From: Nicolas Pitre <hidden> Date: 2012-12-03 16:51:28
On Mon, 3 Dec 2012, Armando Visconti wrote:
On 11/29/2012 12:04 PM, Armando VISCONTI wrote:
quoted
This patch keeps disabled the strict alignment CP15 bit for
all armv6 and armv7 processor without the mmu. This behaviour
is now same as in the mmu case.
Signed-off-by: Armando Visconti<redacted>
---
arch/arm/kernel/head-nommu.S | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
From: Will Deacon <hidden> Date: 2012-12-03 16:55:07
On Mon, Dec 03, 2012 at 04:44:11PM +0000, Armando Visconti wrote:
On 11/29/2012 12:04 PM, Armando VISCONTI wrote:
quoted
This patch keeps disabled the strict alignment CP15 bit for
all armv6 and armv7 processor without the mmu. This behaviour
is now same as in the mmu case.
Signed-off-by: Armando Visconti<redacted>
---
arch/arm/kernel/head-nommu.S | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
Although this is correct, you still need some extra patches to avoid
unaligned accesses to strongly-ordered memory (given that we don't
currently have mainline support for the MPU). Take a look at my nommu/fixes
branch:
https://git.kernel.org/?p=linux/kernel/git/will/linux.git;a=shortlog;h=refs/heads/nommu/fixes
I'm happy to post some of that if it's useful to you.
Will
From: Russell King - ARM Linux <hidden> Date: 2012-12-03 17:29:19
On Mon, Dec 03, 2012 at 05:44:11PM +0100, Armando Visconti wrote:
On 11/29/2012 12:04 PM, Armando VISCONTI wrote:
quoted
This patch keeps disabled the strict alignment CP15 bit for
all armv6 and armv7 processor without the mmu. This behaviour
is now same as in the mmu case.
Signed-off-by: Armando Visconti<redacted>
---
arch/arm/kernel/head-nommu.S | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
From: Will Deacon <hidden> Date: 2012-12-03 17:46:33
On Mon, Dec 03, 2012 at 05:25:53PM +0000, Russell King - ARM Linux wrote:
On Mon, Dec 03, 2012 at 05:44:11PM +0100, Armando Visconti wrote:
quoted
On 11/29/2012 12:04 PM, Armando VISCONTI wrote:
quoted
This patch keeps disabled the strict alignment CP15 bit for
all armv6 and armv7 processor without the mmu. This behaviour
is now same as in the mmu case.
Signed-off-by: Armando Visconti<redacted>
---
arch/arm/kernel/head-nommu.S | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
Well, it brings the nommu version into line with the mmu version, so
it's sensible. Please put it in the patch system, thanks.
In which case, I'll definitely dust-off the patches to prevent unaligned
accesses to strongly-ordered memory because that results in good ol'
UNPREDICTABLE behaviour.
I think Uwe also requires some of the stuff there for his M3 port.
Will
On Mon, Dec 03, 2012 at 05:25:53PM +0000, Russell King - ARM Linux wrote:
quoted
On Mon, Dec 03, 2012 at 05:44:11PM +0100, Armando Visconti wrote:
quoted
On 11/29/2012 12:04 PM, Armando VISCONTI wrote:
quoted
This patch keeps disabled the strict alignment CP15 bit for
all armv6 and armv7 processor without the mmu. This behaviour
is now same as in the mmu case.
Signed-off-by: Armando Visconti<redacted>
---
arch/arm/kernel/head-nommu.S | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
Well, it brings the nommu version into line with the mmu version, so
it's sensible. Please put it in the patch system, thanks.
Done!
In which case, I'll definitely dust-off the patches to prevent unaligned
accesses to strongly-ordered memory because that results in good ol'
UNPREDICTABLE behaviour.
Hello,
On Mon, Dec 03, 2012 at 05:46:17PM +0000, Will Deacon wrote:
On Mon, Dec 03, 2012 at 05:25:53PM +0000, Russell King - ARM Linux wrote:
quoted
On Mon, Dec 03, 2012 at 05:44:11PM +0100, Armando Visconti wrote:
quoted
On 11/29/2012 12:04 PM, Armando VISCONTI wrote:
quoted
This patch keeps disabled the strict alignment CP15 bit for
all armv6 and armv7 processor without the mmu. This behaviour
is now same as in the mmu case.
Signed-off-by: Armando Visconti<redacted>
---
arch/arm/kernel/head-nommu.S | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
Well, it brings the nommu version into line with the mmu version, so
it's sensible. Please put it in the patch system, thanks.
In which case, I'll definitely dust-off the patches to prevent unaligned
accesses to strongly-ordered memory because that results in good ol'
UNPREDICTABLE behaviour.
I think Uwe also requires some of the stuff there for his M3 port.
I didn't check more context than available in the patch and I also
didn't double-check the M3-docs, but AFAIK the M3 doesn't have a cp15
and I noopt this code out.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | http://www.pengutronix.de/ |
From: Will Deacon <hidden> Date: 2012-12-06 10:47:36
On Wed, Dec 05, 2012 at 07:51:34PM +0000, Uwe Kleine-K?nig wrote:
Hello,
Hi Uwe,
On Mon, Dec 03, 2012 at 05:46:17PM +0000, Will Deacon wrote:
quoted
I think Uwe also requires some of the stuff there for his M3 port.
I didn't check more context than available in the patch and I also
didn't double-check the M3-docs, but AFAIK the M3 doesn't have a cp15
and I noopt this code out.
I was thinking more about the word-at-a-time stuff, which relies on
efficient unaligned access for the dcache accesses.
Will