| Message ID | alpine.LFD.2.02.1210221041450.16518@xanadu.home (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Oct 22, 2012 at 02:20:31PM -0400, Nicolas Pitre wrote: > On Mon, 22 Oct 2012, Arnd Bergmann wrote: > > > (adding Nico, who did a lot of the work to get rid of PLAT_PHYS_OFFSET) > > > > On Monday 22 October 2012, Simon Horman wrote: > > > On Mon, Oct 22, 2012 at 09:33:51AM +0900, Simon Horman wrote: > > > > On Fri, Oct 19, 2012 at 08:18:50AM +0000, Arnd Bergmann wrote: > > > > > On Friday 19 October 2012, Simon Horman wrote: > > > > > > * A more significant problem seems to be the use of CONFIG_MEMORY_START > > > > > > to define PLAT_PHYS_OFFSET in arch/arm/mach-shmobile/include/mach/memory.h > > > > > > > > > > > > I'm not sure that I see an easy way to get around this one. > > > > > > > > > > ARM_PATCH_PHYS_VIRT should take care of this, have you tried it? > > > > > > I believe that this leaves mach-shmobile with three areas > > > where CONFIG_MEMORY_START/PLAT_PHYS_OFFSET is used. > > > > Hmm, I just noticed that in fact shmobile is the only remaining > > platform that uses CONFIG_MEMORY_START with a per-board or per-soc > > setting. > > > > > * arch/arm/mach-shmobile/headsmp.S > > > > > > This uses PLAT_PHYS_OFFSET. > > > > > > I believe this can be replaced with a run-time calculation. Though I > > > haven't thought about the details yet. > > What about this (untested): Thanks. I have not managed to successfully test this yet, but I think something like this is the right direction. I will try and massage it into a working version. > > diff --git a/arch/arm/mach-shmobile/headsmp.S b/arch/arm/mach-shmobile/headsmp.S > index b202c12725..9293319fcb 100644 > --- a/arch/arm/mach-shmobile/headsmp.S > +++ b/arch/arm/mach-shmobile/headsmp.S > @@ -64,18 +64,23 @@ ENTRY(v7_invalidate_l1) > mov pc, lr > ENDPROC(v7_invalidate_l1) > > -ENTRY(shmobile_invalidate_start) > +ENTRY(shmobile_secondary_entry) > bl v7_invalidate_l1 > b secondary_startup > -ENDPROC(shmobile_invalidate_start) > +ENDPROC(shmobile_secondary_entry) > > /* > * Reset vector for secondary CPUs. > * This will be mapped at address 0 by SBAR register. > * We need _long_ jump to the physical address. > + * the loaded address is initialized to the physical address of > + * shmobile_secondary_entry > + * in platform_secondary_init(). > */ > + .data > .align 12 > + .arm > ENTRY(shmobile_secondary_vector) > ldr pc, 1f > -1: .long shmobile_invalidate_start - PAGE_OFFSET + PLAT_PHYS_OFFSET > +1: .long 0 > ENDPROC(shmobile_secondary_vector) > diff --git a/arch/arm/mach-shmobile/platsmp.c b/arch/arm/mach-shmobile/platsmp.c > index fde0d23121..356f82da16 100644 > --- a/arch/arm/mach-shmobile/platsmp.c > +++ b/arch/arm/mach-shmobile/platsmp.c > @@ -76,8 +76,14 @@ int shmobile_platform_cpu_kill(unsigned int cpu) > > void __cpuinit platform_secondary_init(unsigned int cpu) > { > + long shmobile_secondary_address; > + > trace_hardirqs_off(); > > + shmobile_secondary_address = (long *)(shmobile_secondary_vector) + 1; > + *shmobile_secondary_address = virt_to_phys(shmobile_secondary_entry); > + __cpuc_flush_dcache_area(shmobile_secondary_address, sizeof(long)); > + > if (is_sh73a0()) > sh73a0_secondary_init(cpu); > > > > > * arch/arm/boot/compressed/head-shmobile.S > > > > > > This makes use of CONFIG_MEMORY_START. > > > This is only used if CONFIG_ZBOOT_ROM is set. > > > > > > I'm unsure if this can be replaced with a run-time calculation or not. > > > But regardless it is only used if CONFIG_ZBOOT_ROM is set, which is not > > > the default at this time. > > This code is meant to be executed from ROM which means a very tailored > kernel configuration. In that case it makes little sense to have > CONFIG_ARM_PATCH_PHYS_VIRT nor CONFIG_AUTO_ZRELADDR turned on anyway. Agreed. > > Right, you can probably make CONFIG_ZBOOT_ROM_MMCIF and > > CONFIG_ZBOOT_ROM_SH_MOBILE_SDHI depend on !ARM_PATCH_PHYS_VIRT > > The right dependency would be CONFIG_AUTO_ZRELADDR, not > ARM_PATCH_PHYS_VIRT. The later concerns the final kernel image, not the > decompressor. Thanks. > > > * arch/arm/mach-shmobile/Makefile.boot > > > > > > This makes use of CONFIG_MEMORY_START to set zreladdr. > > > > > > I believe that the solution to this is to make use of CONFIG_AUTO_ZRELADDR. > > > However, it is not yet clear to me how that can be used in conjunction > > > with a uImage. As I understand it the boot loader on many of our boards, > > > including the Marzen board which is my first target for this work, boot > > > uImage imagess. > > > > If this doesn't work, we probably also need to find a solution to > > build multiple uImage files from the same vmlinux when building a > > multiplatform kernel. > > The right solution to the U-Boot problem is to remove uImage creation > from the kernel entirely. The U-Boot image format should be created at > _installation_ time, not at build time. The fact that the U-Boot image > format is (or was until very recently) inflexible is not Linux's fault. > > If the uImage build target is to remain in the kernel, it should be > marked incompatible with a multi-arch config. There is no point > distributing a multi-arch kernel image when wrapped into a uImage > format. I agree with you reasoning, and that in the long term removing uImage as a target and having an install-time mechanism would be a nice goal. However, I wonder what the way forward is. Provide install-scripts in the kernel tree somewhere? Provide information on the start address under Documentation/ somewhere? While I am more than happy to help address the issues raised in this thread, and others that arise. There do seem to be a number of issues between where we are now and a more generic shmobile_defconfig. I would like consideration given to allowing the exixting, working, well-maintained, per-board defconfigs to be updated until these issues have been resolved.
On Tuesday 30 October 2012, Simon Horman wrote: > While I am more than happy to help address the issues raised in this > thread, and others that arise. There do seem to be a number of issues > between where we are now and a more generic shmobile_defconfig. I would > like consideration given to allowing the exixting, working, well-maintained, > per-board defconfigs to be updated until these issues have been resolved. Yes, no problem. This seemed like a low-hanging fruit initially but has turned into something much bigger now. Instead of attacking all these at ones, we can leave them as something worthwhile doing later. I noticed that out of the 11 shmobile defconfigs, only three (marzen, kzm9d and kzm9g) actually have a nonzero MEMORY_START. Maybe it's possible to consolidate all or some of the others first, since they should still work with the same uImage at the expense of just making the early debugging a little harder, as we discussed earlier. For all I know, these three boards are also the ones seeing the most ongoing development, so you could start by using a shared defconfig for the oldest (ARM11 based) boards at first that are also less likely to impact new development starting from the defconfig. Arnd
On Tue, Oct 30, 2012 at 09:41:27PM +0000, Arnd Bergmann wrote: > On Tuesday 30 October 2012, Simon Horman wrote: > > While I am more than happy to help address the issues raised in this > > thread, and others that arise. There do seem to be a number of issues > > between where we are now and a more generic shmobile_defconfig. I would > > like consideration given to allowing the exixting, working, well-maintained, > > per-board defconfigs to be updated until these issues have been resolved. > > Yes, no problem. This seemed like a low-hanging fruit initially but has > turned into something much bigger now. > > Instead of attacking all these at ones, we can leave them as something > worthwhile doing later. I noticed that out of the 11 shmobile defconfigs, > only three (marzen, kzm9d and kzm9g) actually have a nonzero MEMORY_START. > > Maybe it's possible to consolidate all or some of the others first, since > they should still work with the same uImage at the expense of just making > the early debugging a little harder, as we discussed earlier. > > For all I know, these three boards are also the ones seeing the most > ongoing development, so you could start by using a shared defconfig > for the oldest (ARM11 based) boards at first that are also less likely > to impact new development starting from the defconfig. Thanks, good observations. I will look into that. My expectation is that marzen and kzm9g will continue to see heavy development in the near future.
diff --git a/arch/arm/mach-shmobile/headsmp.S b/arch/arm/mach-shmobile/headsmp.S index b202c12725..9293319fcb 100644 --- a/arch/arm/mach-shmobile/headsmp.S +++ b/arch/arm/mach-shmobile/headsmp.S @@ -64,18 +64,23 @@ ENTRY(v7_invalidate_l1) mov pc, lr ENDPROC(v7_invalidate_l1) -ENTRY(shmobile_invalidate_start) +ENTRY(shmobile_secondary_entry) bl v7_invalidate_l1 b secondary_startup -ENDPROC(shmobile_invalidate_start) +ENDPROC(shmobile_secondary_entry) /* * Reset vector for secondary CPUs. * This will be mapped at address 0 by SBAR register. * We need _long_ jump to the physical address. + * the loaded address is initialized to the physical address of + * shmobile_secondary_entry + * in platform_secondary_init(). */ + .data .align 12 + .arm ENTRY(shmobile_secondary_vector) ldr pc, 1f -1: .long shmobile_invalidate_start - PAGE_OFFSET + PLAT_PHYS_OFFSET +1: .long 0 ENDPROC(shmobile_secondary_vector) diff --git a/arch/arm/mach-shmobile/platsmp.c b/arch/arm/mach-shmobile/platsmp.c index fde0d23121..356f82da16 100644 --- a/arch/arm/mach-shmobile/platsmp.c +++ b/arch/arm/mach-shmobile/platsmp.c @@ -76,8 +76,14 @@ int shmobile_platform_cpu_kill(unsigned int cpu) void __cpuinit platform_secondary_init(unsigned int cpu) { + long shmobile_secondary_address; + trace_hardirqs_off(); + shmobile_secondary_address = (long *)(shmobile_secondary_vector) + 1; + *shmobile_secondary_address = virt_to_phys(shmobile_secondary_entry); + __cpuc_flush_dcache_area(shmobile_secondary_address, sizeof(long)); + if (is_sh73a0()) sh73a0_secondary_init(cpu);