arm: drop Execute-In-Place

nearly no-one use it, only amop1, pxa and sa1100 implement it

this is the only reason why we need to keep the PLAT_PHY_OFFSET and do not enable the "Patch physical to virtual translations at runtime" support when have MMU enabled

As done on AT91

Signed-off-by Jean-Christophe PLAGNIOL-VILLARD <[email protected]>

Cc Russell King <[email protected]>

Cc Nicolas Pitre <[email protected]>

Cc Eric Miao <[email protected]>

Cc Tony Lindgren <[email protected]>

Cc Nicolas Ferre <[email protected]>

Quoted 1 line · Jean-Christophe PLAGNIOL-VILLARD

nearly no-one use it, only amop1, pxa and sa1100 implement it

What's amop1?

Quoted 4 lines

this is the only reason why we need to keep the PLAT_PHY_OFFSET and do not enable the "Patch physical to virtual translations at runtime" support when have MMU enabled

I'm actually poking around several SoCs that have relatively large and fast NOR flash and they do use XIP.

Quoted 9 lines

As done on AT91

Signed-off-by Jean-Christophe PLAGNIOL-VILLARD <[email protected]>

Cc Russell King <[email protected]>

Cc Nicolas Pitre <[email protected]>

Cc Eric Miao <[email protected]>

Cc Tony Lindgren <[email protected]>

Cc Nicolas Ferre <[email protected]>

So this is most definitely a NAK from my side. By killing XIP we're moving Linux kernel out of Automotive scope.

I'd rather let at91 go.

nearly no-one use it, only amop1, pxa and sa1100 implement it

Quoted 1 line · Jean-Christophe PLAGNIOL-VILLARD

nearly no-one use it, only amop1, pxa and sa1100 implement it

Sony uses this - a lot. Principally we're using this on a NEC naviengine part, which is ARM11MPCore based, support for which is (sadly) out of tree.

I'd like to see MORE support for XIP in the kernel, not less.

NAK from me.

Quoted 6 lines · Tim Bird

Quoted 1 line · Jean-Christophe PLAGNIOL-VILLARD

nearly no-one use it, only amop1, pxa and sa1100 implement it

Sony uses this - a lot. Principally we're using this on a NEC naviengine part, which is ARM11MPCore based, support for which is (sadly) out of tree.

Quoted 7 lines · Tim Bird

Quoted 6 lines · Tim Bird

Quoted 1 line · Jean-Christophe PLAGNIOL-VILLARD

nearly no-one use it, only amop1, pxa and sa1100 implement it

Sony uses this - a lot. Principally we're using this on a NEC naviengine part, which is ARM11MPCore based, support for which is (sadly) out of tree.

If you're out of tree, you don't exist.

Quoted 9 lines · David Woodhouse

Quoted 7 lines · Tim Bird

Quoted 6 lines · Tim Bird

Quoted 1 line · Jean-Christophe PLAGNIOL-VILLARD

nearly no-one use it, only amop1, pxa and sa1100 implement it

Sony uses this - a lot. Principally we're using this on a NEC naviengine part, which is ARM11MPCore based, support for which is (sadly) out of tree.

Quoted 1 line

If you're out of tree, you don't exist.

Yeah - I know. I guess I should tell NEC we'll drop support for their chip and move to another one that supports XIP if they don't get their act together. If XIP survives...

Quoted 10 lines · Tim Bird

Quoted 9 lines · David Woodhouse

Quoted 7 lines · Tim Bird

Quoted 6 lines · Tim Bird

Quoted 1 line · Jean-Christophe PLAGNIOL-VILLARD

nearly no-one use it, only amop1, pxa and sa1100 implement it

Sony uses this - a lot. ?Principally we're using this on a NEC naviengine part, which is ARM11MPCore based, support for which is (sadly) out of tree.

Quoted 5 lines

Quoted 1 line

If you're out of tree, you don't exist.

Yeah - I know. ?I guess I should tell NEC we'll drop support for their chip and move to another one that supports XIP if they don't get their act together. ?If XIP survives...

It is easy enough to keep it alive... as long as someone uses it of course.

Quoted 17 lines · Nicolas Pitre

Quoted 15 lines · Tim Bird

Quoted 10 lines · David Woodhouse

Quoted 7 lines · Tim Bird

Quoted 6 lines · Tim Bird

Quoted 1 line · Jean-Christophe PLAGNIOL-VILLARD

nearly no-one use it, only amop1, pxa and sa1100 implement it

Sony uses this - a lot. Principally we're using this on a NEC naviengine part, which is ARM11MPCore based, support for which is (sadly) out of tree.

If you're out of tree, you don't exist.

Yeah - I know. I guess I should tell NEC we'll drop support for their chip and move to another one that supports XIP if they don't get their act together. If XIP survives...

Quoted 2 lines

It is easy enough to keep it alive... as long as someone uses it of course.

i think David's point:
... someone <in tree> uses it ...

Quoted 18 lines · Mike Frysinger

Quoted 17 lines · Nicolas Pitre

Quoted 15 lines · Tim Bird

Quoted 10 lines · David Woodhouse

Quoted 7 lines · Tim Bird

Quoted 6 lines · Tim Bird

Quoted 1 line · Jean-Christophe PLAGNIOL-VILLARD

nearly no-one use it, only amop1, pxa and sa1100 implement it

Sony uses this - a lot. Principally we're using this on a NEC naviengine part, which is ARM11MPCore based, support for which is (sadly) out of tree.

If you're out of tree, you don't exist.

Yeah - I know. I guess I should tell NEC we'll drop support for their chip and move to another one that supports XIP if they don't get their act together. If XIP survives...

Quoted 5 lines

Quoted 2 lines

It is easy enough to keep it alive... as long as someone uses it of course.

i think David's point:
... someone <in tree> uses it ...

I should add that I tried to use XIP on omap (for research purposes), but it was broken and I didn't have time to fix it. My bad.

If anyone is using XIP on in-tree platforms, I'd like to hear about it.

As for in-tree-ness - I thought the most recent message was to stay out of tree until the refactoring was over. ;-)

Just to be clear... We have XIP in the tree already. ?If it is useful to someone, in-tree or out-of-tree, then it is worth keeping around. Even if the only user was out-of-tree which certainly wasn't the case when I added XIP support to the kernel, then ripping it out and adding it back later would be more trouble than preserving it.

What I was asking recently is whether or not XIP is still useful to someone today. ?Apparently it is, which is the answer I was looking for.

Quoted 3 lines · Tim Bird

I should add that I tried to use XIP on omap (for research purposes), but it was broken and I didn't have time to fix it. My bad.

OMAP is doing pretty nasty things with their early serial port support. This is most likely to screw up XIP.

Quoted 21 lines · Mike Frysinger

Quoted 19 lines · Nicolas Pitre

Quoted 10 lines · Tim Bird

Quoted 9 lines · David Woodhouse

Quoted 7 lines · Tim Bird

Quoted 6 lines · Tim Bird

Quoted 1 line · Jean-Christophe PLAGNIOL-VILLARD

nearly no-one use it, only amop1, pxa and sa1100 implement it

Sony uses this - a lot. ?Principally we're using this on a NEC naviengine part, which is ARM11MPCore based, support for which is (sadly) out of tree.

Quoted 5 lines

Quoted 1 line

If you're out of tree, you don't exist.

Yeah - I know. ?I guess I should tell NEC we'll drop support for their chip and move to another one that supports XIP if they don't get their act together. ?If XIP survives...

It is easy enough to keep it alive... as long as someone uses it of course.

Quoted 2 lines

i think David's point:
... someone <in tree> uses it ...

I should add that I tried to use XIP on omap (for research purposes), but it was broken and I didn't have time to fix it. ?My bad. If anyone is using XIP on in-tree platforms, I'd like to hear about it.

As for in-tree-ness - I thought the most recent message was to stay out of tree until the refactoring was over. ;-)

Quoted 22 lines · Tim Bird

Quoted 21 lines · Mike Frysinger

Quoted 19 lines · Nicolas Pitre

Quoted 10 lines · Tim Bird

Quoted 9 lines · David Woodhouse

Quoted 7 lines · Tim Bird

Quoted 6 lines · Tim Bird

Quoted 1 line · Jean-Christophe PLAGNIOL-VILLARD

nearly no-one use it, only amop1, pxa and sa1100 implement it

Sony uses this - a lot. Principally we're using this on a NEC naviengine part, which is ARM11MPCore based, support for which is (sadly) out of tree.

Quoted 5 lines

Quoted 1 line

If you're out of tree, you don't exist.

Yeah - I know. I guess I should tell NEC we'll drop support for their chip and move to another one that supports XIP if they don't get their act together. If XIP survives...

It is easy enough to keep it alive... as long as someone uses it of course.

Quoted 7 lines

Quoted 2 lines

i think David's point:
... someone <in tree> uses it ...

I should add that I tried to use XIP on omap (for research purposes), but it was broken and I didn't have time to fix it. My bad. If anyone is using XIP on in-tree platforms, I'd like to hear about it.

XIP on Blackfin should work right now, but that doesnt directly apply to the patch in question here. it does however imply that other pieces in the stack work (like the MTD/mm layers).

Quoted 2 lines

As for in-tree-ness - I thought the most recent message was to stay out of tree until the refactoring was over. ;-)

to be fair, does this have any relevance whatsoever to NEC parts ? istm that the hindrance here is NEC doing any actual work for mainline. even if there was no refactoring, i find it hard to believe that an NEC port would be posted. if it were actually something that could happen, then they should already be posting patches for *basic* review to get the pieces unrelated to the refactoring worked out. there's no reason this has to be done serially.

Quoted 11 lines · Mike Frysinger

Quoted 2 lines · Tim Bird

As for in-tree-ness - I thought the most recent message was to stay out of tree until the refactoring was over. ;-)

to be fair, does this have any relevance whatsoever to NEC parts ? istm that the hindrance here is NEC doing any actual work for mainline. ?even if there was no refactoring, i find it hard to believe that an NEC port would be posted. ?if it were actually something that could happen, then they should already be posting patches for *basic* review to get the pieces unrelated to the refactoring worked out. there's no reason this has to be done serially.

Well, OK. ?I just don't want to lob bombs at NEC and then have some poor soul over there get immediately rebuffed, due to basic ARM churn. ?Maybe not having naviengine support upstream is my fault, but Sony doesn't make the CPU, so it doesn't seem like it should be my job to mainline the chip support. ?About the only thing I have at my disposal is pressure not to buy the chip (but this is harder to exercise than one might think.)

Quoted 13 lines · Tim Bird

Quoted 11 lines · Mike Frysinger

Quoted 2 lines · Tim Bird

As for in-tree-ness - I thought the most recent message was to stay out of tree until the refactoring was over. ;-)

to be fair, does this have any relevance whatsoever to NEC parts ? istm that the hindrance here is NEC doing any actual work for mainline. ?even if there was no refactoring, i find it hard to believe that an NEC port would be posted. ?if it were actually something that could happen, then they should already be posting patches for *basic* review to get the pieces unrelated to the refactoring worked out. there's no reason this has to be done serially.

Quoted 7 lines

Well, OK. ?I just don't want to lob bombs at NEC and then have some poor soul over there get immediately rebuffed, due to basic ARM churn. ?Maybe not having naviengine support upstream is my fault, but Sony doesn't make the CPU, so it doesn't seem like it should be my job to mainline the chip support. ?About the only thing I have at my disposal is pressure not to buy the chip (but this is harder to exercise than one might think.)

i dont have any vested interest either way wrt NEC or ARM/XIP. i was just trying to highlight what i saw as a red herring.

i think the axiom "post early & post often" holds just as true here.

Quoted 1 line · Jean-Christophe PLAGNIOL-VILLARD

nearly no-one use it, only amop1, pxa and sa1100 implement it

Sony uses this - a lot. Principally we're using this on a NEC naviengine part, which is ARM11MPCore based, support for which is (sadly) out of tree.

I'd like to see MORE support for XIP in the kernel, not less.

Quoted 7 lines · Tim Bird

Quoted 1 line · Jean-Christophe PLAGNIOL-VILLARD

nearly no-one use it, only amop1, pxa and sa1100 implement it

Sony uses this - a lot. Principally we're using this on a NEC naviengine part, which is ARM11MPCore based, support for which is (sadly) out of tree.

Quoted 1 line

I'd like to see MORE support for XIP in the kernel, not less.

OK. If done properly, there shouldn't be any need to drop XIP support. However, given that XIP is already a specialized configuration that is handled by hardware experts, in the future you might have to provide at kernel configuration time the actual physical address of your RAM as it is currently done for the ROM address where the kernel image is located.

Sony uses this - a lot. ?Principally we're using this on a NEC naviengine part, which is ARM11MPCore based, support for which is (sadly) out of tree.

From [email protected] Sun May 8 19:27:37 2011