Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Tue, 2008-11-11 at 08:19 -0500, Josh Boyer wrote:
On Fri, Oct 31, 2008 at 06:23:28PM -0500, Hollis Blanchard wrote:
On Wed, Oct 22, 2008 at 9:28 AM, Christian Ehrhardt
[EMAIL PROTECTED] wrote:
Hi Ilya,
I just tried your patch on my 440 board because it would help us in our
environment.
Unfortunately I run into a bug on early boot (mark_bootmem).
A log can be found in this mail, this is the bug when running with 64k page
size.
I tried this with and without your 2/2 265k patch and also with page size
configured to 16k, the error is the same in all cases.
I used an earlier version of your patch in the past and it worked fine.
Applying this old patch causes the same problem.
Therefore I expect that there was some other code changed that breaks with
page size != 4k.
This patch seems to solve the problem for me, but I have to run and
haven't yet worked out if it's the right fix.
diff --git a/mm/bootmem.c b/mm/bootmem.c
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -300,7 +300,7 @@ static int __init mark_bootmem(unsigned
unsigned long max;
if (pos bdata-node_min_pfn ||
- pos = bdata-node_low_pfn) {
+ pos bdata-node_low_pfn) {
BUG_ON(pos != start);
continue;
}
@@ -399,7 +399,7 @@ int __init reserve_bootmem(unsigned long
unsigned long start, end;
start = PFN_DOWN(addr);
- end = PFN_UP(addr + size);
+ end = PFN_DOWN(addr + size);
return mark_bootmem(start, end, 1, flags);
}
Hollis, if I'm understanding things correctly this patch is no
longer needed if we do the memory reserve in the boot wrapper for
the errata. Correct?
Correct.
--
Hollis Blanchard
IBM Linux Technology Center
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Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Fri, Oct 31, 2008 at 06:23:28PM -0500, Hollis Blanchard wrote:
On Wed, Oct 22, 2008 at 9:28 AM, Christian Ehrhardt
[EMAIL PROTECTED] wrote:
Hi Ilya,
I just tried your patch on my 440 board because it would help us in our
environment.
Unfortunately I run into a bug on early boot (mark_bootmem).
A log can be found in this mail, this is the bug when running with 64k page
size.
I tried this with and without your 2/2 265k patch and also with page size
configured to 16k, the error is the same in all cases.
I used an earlier version of your patch in the past and it worked fine.
Applying this old patch causes the same problem.
Therefore I expect that there was some other code changed that breaks with
page size != 4k.
This patch seems to solve the problem for me, but I have to run and
haven't yet worked out if it's the right fix.
diff --git a/mm/bootmem.c b/mm/bootmem.c
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -300,7 +300,7 @@ static int __init mark_bootmem(unsigned
unsigned long max;
if (pos bdata-node_min_pfn ||
- pos = bdata-node_low_pfn) {
+ pos bdata-node_low_pfn) {
BUG_ON(pos != start);
continue;
}
@@ -399,7 +399,7 @@ int __init reserve_bootmem(unsigned long
unsigned long start, end;
start = PFN_DOWN(addr);
- end = PFN_UP(addr + size);
+ end = PFN_DOWN(addr + size);
return mark_bootmem(start, end, 1, flags);
}
Hollis, if I'm understanding things correctly this patch is no
longer needed if we do the memory reserve in the boot wrapper for
the errata. Correct?
josh
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Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Mon, 2008-11-03 at 15:00 -0500, Josh Boyer wrote:
On Mon, 03 Nov 2008 13:55:21 -0600
Hollis Blanchard [EMAIL PROTECTED] wrote:
On Mon, 2008-11-03 at 11:43 +1100, Benjamin Herrenschmidt wrote:
Cropping the size of the memory node. That was simplest to do from the
cuboot wrapper at the time. If marking it reserved via a reserve map
is more elegant and correct, we could do that.
But I will still like to know what about the other way is hairy please.
I don't like it :-) Bad feeling ... don't like having a memory
node entry that isn't aligned to some large power of two typically.
More specifically, mm/bootmem.c seems to be making the implicit
assumption that memory size is an even multiple of PAGE_SIZE. With 4K
pages, 0x000 bytes of RAM fits; with 64K pages it does not.
Hmm.. I dunno what to think about that. Again, how does mem= play
into this? (I will look myself in a bit, but if someone knows offhand
that would be nice..)
Using the device tree reserve map stuff does indeed seem to solve the
problem. However, I really don't understand the layering in
arch/powerpc/boot at all, so I'll just put this patch out here and
people can play with wrappers and prototypes all they want:
This actually looks pretty nice. I'll wait for David to Ack the fdt
parts.
David?
--
Hollis Blanchard
IBM Linux Technology Center
powerpc/4xx: work around CHIP11 errata in a more PAGE_SIZE-friendly way
The current CHIP11 errata truncates the device tree memory node, and
assumes a
4K page size. This breaks kernels with non-4K PAGE_SIZE.
Instead, use a device tree memory reservation to reserve only the 256 bytes
actually affected by the errata, leaving the total memory size unaltered.
Signed-off-by: Hollis Blanchard [EMAIL PROTECTED]
diff --git a/arch/powerpc/boot/4xx.c b/arch/powerpc/boot/4xx.c
--- a/arch/powerpc/boot/4xx.c
+++ b/arch/powerpc/boot/4xx.c
@@ -21,7 +21,7 @@
#include reg.h
#include dcr.h
-static unsigned long chip_11_errata(unsigned long memsize)
+static void chip_11_errata(unsigned long memsize)
{
unsigned long pvr;
@@ -31,13 +31,11 @@ static unsigned long chip_11_errata(unsi
case 0x4850:
case 0x48d0:
case 0x28d0:
- memsize -= 4096;
+ fdt_reserve_mem(memsize - 256, 256);
break;
default:
break;
}
-
- return memsize;
}
/* Read the 4xx SDRAM controller to get size of system memory. */
@@ -53,7 +51,7 @@ void ibm4xx_sdram_fixup_memsize(void)
memsize += SDRAM_CONFIG_BANK_SIZE(bank_config);
}
- memsize = chip_11_errata(memsize);
+ chip_11_errata(memsize);
dt_fixup_memory(0, memsize);
}
@@ -219,7 +217,7 @@ void ibm4xx_denali_fixup_memsize(void)
bank = 4; /* 4 banks */
memsize = cs * (1 (col+row)) * bank * dpath;
- memsize = chip_11_errata(memsize);
+ chip_11_errata(memsize);
dt_fixup_memory(0, memsize);
}
diff --git a/arch/powerpc/boot/libfdt-wrapper.c
b/arch/powerpc/boot/libfdt-wrapper.c
--- a/arch/powerpc/boot/libfdt-wrapper.c
+++ b/arch/powerpc/boot/libfdt-wrapper.c
@@ -167,6 +167,11 @@ static unsigned long fdt_wrapper_finaliz
return (unsigned long)fdt;
}
+int fdt_reserve_mem(unsigned long addr, unsigned long bytes)
+{
+ return fdt_add_mem_rsv(fdt, addr, bytes);
+}
+
void fdt_init(void *blob)
{
int err;
diff --git a/arch/powerpc/boot/ops.h b/arch/powerpc/boot/ops.h
--- a/arch/powerpc/boot/ops.h
+++ b/arch/powerpc/boot/ops.h
@@ -83,6 +83,7 @@ extern struct loader_info loader_info;
void start(void);
void fdt_init(void *blob);
+int fdt_reserve_mem(unsigned long addr, unsigned long bytes);
int serial_console_init(void);
int ns16550_console_init(void *devp, struct serial_console_data *scdp);
int mpsc_console_init(void *devp, struct serial_console_data *scdp);
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Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Wed, Nov 05, 2008 at 11:33:28AM -0600, Hollis Blanchard wrote: On Mon, 2008-11-03 at 15:00 -0500, Josh Boyer wrote: On Mon, 03 Nov 2008 13:55:21 -0600 Hollis Blanchard [EMAIL PROTECTED] wrote: On Mon, 2008-11-03 at 11:43 +1100, Benjamin Herrenschmidt wrote: Cropping the size of the memory node. That was simplest to do from the cuboot wrapper at the time. If marking it reserved via a reserve map is more elegant and correct, we could do that. But I will still like to know what about the other way is hairy please. I don't like it :-) Bad feeling ... don't like having a memory node entry that isn't aligned to some large power of two typically. More specifically, mm/bootmem.c seems to be making the implicit assumption that memory size is an even multiple of PAGE_SIZE. With 4K pages, 0x000 bytes of RAM fits; with 64K pages it does not. Hmm.. I dunno what to think about that. Again, how does mem= play into this? (I will look myself in a bit, but if someone knows offhand that would be nice..) Using the device tree reserve map stuff does indeed seem to solve the problem. However, I really don't understand the layering in arch/powerpc/boot at all, so I'll just put this patch out here and people can play with wrappers and prototypes all they want: This actually looks pretty nice. I'll wait for David to Ack the fdt parts. David? Sorry, I've been on leave for a few days. I assume you mean the new call through to fdt_add_mem_rsv(). Hrm.. currently all the things in fdt_wrapper are hooks called through dt_ops. Adding such a trivial wrapper seems a little silly. There have been other people wanting to use other libfdt features directly, knowing that they have a flat tree on their system. I think it would be more sensible, I think, to just expose the global fdt pointer, so that people can use the libfdt functions directly, without having to go through the wrapper code. Unless of course there is occasion to use this add reserve callback on real OF systems, in which case it should be a new dt_ops hook. -- David Gibson| I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Mon, 03 Nov 2008 11:43:54 +1100 Benjamin Herrenschmidt [EMAIL PROTECTED] wrote: Cropping the size of the memory node. That was simplest to do from the cuboot wrapper at the time. If marking it reserved via a reserve map is more elegant and correct, we could do that. But I will still like to know what about the other way is hairy please. I don't like it :-) Bad feeling ... don't like having a memory node entry that isn't aligned to some large power of two typically. Erm, ok. And does your heebie-geebies extend to people using the mem= parameter in a similar fashion? josh ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Mon, 2008-11-03 at 11:43 +1100, Benjamin Herrenschmidt wrote:
Cropping the size of the memory node. That was simplest to do from the
cuboot wrapper at the time. If marking it reserved via a reserve map
is more elegant and correct, we could do that.
But I will still like to know what about the other way is hairy please.
I don't like it :-) Bad feeling ... don't like having a memory
node entry that isn't aligned to some large power of two typically.
More specifically, mm/bootmem.c seems to be making the implicit
assumption that memory size is an even multiple of PAGE_SIZE. With 4K
pages, 0x000 bytes of RAM fits; with 64K pages it does not.
Using the device tree reserve map stuff does indeed seem to solve the
problem. However, I really don't understand the layering in
arch/powerpc/boot at all, so I'll just put this patch out here and
people can play with wrappers and prototypes all they want:
powerpc/4xx: work around CHIP11 errata in a more PAGE_SIZE-friendly way
The current CHIP11 errata truncates the device tree memory node, and assumes a
4K page size. This breaks kernels with non-4K PAGE_SIZE.
Instead, use a device tree memory reservation to reserve only the 256 bytes
actually affected by the errata, leaving the total memory size unaltered.
Signed-off-by: Hollis Blanchard [EMAIL PROTECTED]
diff --git a/arch/powerpc/boot/4xx.c b/arch/powerpc/boot/4xx.c
--- a/arch/powerpc/boot/4xx.c
+++ b/arch/powerpc/boot/4xx.c
@@ -21,7 +21,7 @@
#include reg.h
#include dcr.h
-static unsigned long chip_11_errata(unsigned long memsize)
+static void chip_11_errata(unsigned long memsize)
{
unsigned long pvr;
@@ -31,13 +31,11 @@ static unsigned long chip_11_errata(unsi
case 0x4850:
case 0x48d0:
case 0x28d0:
- memsize -= 4096;
+ fdt_reserve_mem(memsize - 256, 256);
break;
default:
break;
}
-
- return memsize;
}
/* Read the 4xx SDRAM controller to get size of system memory. */
@@ -53,7 +51,7 @@ void ibm4xx_sdram_fixup_memsize(void)
memsize += SDRAM_CONFIG_BANK_SIZE(bank_config);
}
- memsize = chip_11_errata(memsize);
+ chip_11_errata(memsize);
dt_fixup_memory(0, memsize);
}
@@ -219,7 +217,7 @@ void ibm4xx_denali_fixup_memsize(void)
bank = 4; /* 4 banks */
memsize = cs * (1 (col+row)) * bank * dpath;
- memsize = chip_11_errata(memsize);
+ chip_11_errata(memsize);
dt_fixup_memory(0, memsize);
}
diff --git a/arch/powerpc/boot/libfdt-wrapper.c
b/arch/powerpc/boot/libfdt-wrapper.c
--- a/arch/powerpc/boot/libfdt-wrapper.c
+++ b/arch/powerpc/boot/libfdt-wrapper.c
@@ -167,6 +167,11 @@ static unsigned long fdt_wrapper_finaliz
return (unsigned long)fdt;
}
+int fdt_reserve_mem(unsigned long addr, unsigned long bytes)
+{
+ return fdt_add_mem_rsv(fdt, addr, bytes);
+}
+
void fdt_init(void *blob)
{
int err;
diff --git a/arch/powerpc/boot/ops.h b/arch/powerpc/boot/ops.h
--- a/arch/powerpc/boot/ops.h
+++ b/arch/powerpc/boot/ops.h
@@ -83,6 +83,7 @@ extern struct loader_info loader_info;
void start(void);
void fdt_init(void *blob);
+int fdt_reserve_mem(unsigned long addr, unsigned long bytes);
int serial_console_init(void);
int ns16550_console_init(void *devp, struct serial_console_data *scdp);
int mpsc_console_init(void *devp, struct serial_console_data *scdp);
--
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IBM Linux Technology Center
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Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Mon, 03 Nov 2008 13:55:21 -0600
Hollis Blanchard [EMAIL PROTECTED] wrote:
On Mon, 2008-11-03 at 11:43 +1100, Benjamin Herrenschmidt wrote:
Cropping the size of the memory node. That was simplest to do from the
cuboot wrapper at the time. If marking it reserved via a reserve map
is more elegant and correct, we could do that.
But I will still like to know what about the other way is hairy please.
I don't like it :-) Bad feeling ... don't like having a memory
node entry that isn't aligned to some large power of two typically.
More specifically, mm/bootmem.c seems to be making the implicit
assumption that memory size is an even multiple of PAGE_SIZE. With 4K
pages, 0x000 bytes of RAM fits; with 64K pages it does not.
Hmm.. I dunno what to think about that. Again, how does mem= play
into this? (I will look myself in a bit, but if someone knows offhand
that would be nice..)
Using the device tree reserve map stuff does indeed seem to solve the
problem. However, I really don't understand the layering in
arch/powerpc/boot at all, so I'll just put this patch out here and
people can play with wrappers and prototypes all they want:
This actually looks pretty nice. I'll wait for David to Ack the fdt
parts.
josh
powerpc/4xx: work around CHIP11 errata in a more PAGE_SIZE-friendly way
The current CHIP11 errata truncates the device tree memory node, and assumes a
4K page size. This breaks kernels with non-4K PAGE_SIZE.
Instead, use a device tree memory reservation to reserve only the 256 bytes
actually affected by the errata, leaving the total memory size unaltered.
Signed-off-by: Hollis Blanchard [EMAIL PROTECTED]
diff --git a/arch/powerpc/boot/4xx.c b/arch/powerpc/boot/4xx.c
--- a/arch/powerpc/boot/4xx.c
+++ b/arch/powerpc/boot/4xx.c
@@ -21,7 +21,7 @@
#include reg.h
#include dcr.h
-static unsigned long chip_11_errata(unsigned long memsize)
+static void chip_11_errata(unsigned long memsize)
{
unsigned long pvr;
@@ -31,13 +31,11 @@ static unsigned long chip_11_errata(unsi
case 0x4850:
case 0x48d0:
case 0x28d0:
- memsize -= 4096;
+ fdt_reserve_mem(memsize - 256, 256);
break;
default:
break;
}
-
- return memsize;
}
/* Read the 4xx SDRAM controller to get size of system memory. */
@@ -53,7 +51,7 @@ void ibm4xx_sdram_fixup_memsize(void)
memsize += SDRAM_CONFIG_BANK_SIZE(bank_config);
}
- memsize = chip_11_errata(memsize);
+ chip_11_errata(memsize);
dt_fixup_memory(0, memsize);
}
@@ -219,7 +217,7 @@ void ibm4xx_denali_fixup_memsize(void)
bank = 4; /* 4 banks */
memsize = cs * (1 (col+row)) * bank * dpath;
- memsize = chip_11_errata(memsize);
+ chip_11_errata(memsize);
dt_fixup_memory(0, memsize);
}
diff --git a/arch/powerpc/boot/libfdt-wrapper.c
b/arch/powerpc/boot/libfdt-wrapper.c
--- a/arch/powerpc/boot/libfdt-wrapper.c
+++ b/arch/powerpc/boot/libfdt-wrapper.c
@@ -167,6 +167,11 @@ static unsigned long fdt_wrapper_finaliz
return (unsigned long)fdt;
}
+int fdt_reserve_mem(unsigned long addr, unsigned long bytes)
+{
+ return fdt_add_mem_rsv(fdt, addr, bytes);
+}
+
void fdt_init(void *blob)
{
int err;
diff --git a/arch/powerpc/boot/ops.h b/arch/powerpc/boot/ops.h
--- a/arch/powerpc/boot/ops.h
+++ b/arch/powerpc/boot/ops.h
@@ -83,6 +83,7 @@ extern struct loader_info loader_info;
void start(void);
void fdt_init(void *blob);
+int fdt_reserve_mem(unsigned long addr, unsigned long bytes);
int serial_console_init(void);
int ns16550_console_init(void *devp, struct serial_console_data *scdp);
int mpsc_console_init(void *devp, struct serial_console_data *scdp);
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Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Mon, 2008-11-03 at 06:26 -0500, Josh Boyer wrote: On Mon, 03 Nov 2008 11:43:54 +1100 Benjamin Herrenschmidt [EMAIL PROTECTED] wrote: Cropping the size of the memory node. That was simplest to do from the cuboot wrapper at the time. If marking it reserved via a reserve map is more elegant and correct, we could do that. But I will still like to know what about the other way is hairy please. I don't like it :-) Bad feeling ... don't like having a memory node entry that isn't aligned to some large power of two typically. Erm, ok. And does your heebie-geebies extend to people using the mem= parameter in a similar fashion? Nah, not really. It's not that it won't work, I suppose it does, though I would have preferred a way to reserve that memory rather than take it off. In fact, that last page could be used for other things, for example it could be used as a dummy page to point stale DMA to or whatever else. Ben. ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Sun, Nov 02, 2008 at 08:55:02AM +1100, Benjamin Herrenschmidt wrote: On Sat, 2008-11-01 at 07:30 -0400, Josh Boyer wrote: That is on purpose. The chip has an errata that causes badness if you use the last XX bytes of DRAM. I forget exactly what XX is, but we just remove the last page. Doing that from the device-tree is very hairy tho... you end up with informations in there that aren't aligned etc... oh well. What? -ENOTVERBOSEENOUGH. I don't see how this is really different from U-Boot just passing in a smaller memory size in the old arch/ppc world. (And I think U-Boot will actually fixup the device tree in a similar manner itself these days.) So if there are problems with this, please do tell. josh ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Sun, 2008-11-02 at 08:41 -0500, Josh Boyer wrote: On Sun, Nov 02, 2008 at 08:55:02AM +1100, Benjamin Herrenschmidt wrote: On Sat, 2008-11-01 at 07:30 -0400, Josh Boyer wrote: That is on purpose. The chip has an errata that causes badness if you use the last XX bytes of DRAM. I forget exactly what XX is, but we just remove the last page. Doing that from the device-tree is very hairy tho... you end up with informations in there that aren't aligned etc... oh well. What? -ENOTVERBOSEENOUGH. I don't see how this is really different from U-Boot just passing in a smaller memory size in the old arch/ppc world. (And I think U-Boot will actually fixup the device tree in a similar manner itself these days.) So if there are problems with this, please do tell. Is it cropping the memory nodes or using the reserve map ? Ben. ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Mon, 03 Nov 2008 08:33:16 +1100 Benjamin Herrenschmidt [EMAIL PROTECTED] wrote: On Sun, 2008-11-02 at 08:41 -0500, Josh Boyer wrote: On Sun, Nov 02, 2008 at 08:55:02AM +1100, Benjamin Herrenschmidt wrote: On Sat, 2008-11-01 at 07:30 -0400, Josh Boyer wrote: That is on purpose. The chip has an errata that causes badness if you use the last XX bytes of DRAM. I forget exactly what XX is, but we just remove the last page. Doing that from the device-tree is very hairy tho... you end up with informations in there that aren't aligned etc... oh well. What? -ENOTVERBOSEENOUGH. I don't see how this is really different from U-Boot just passing in a smaller memory size in the old arch/ppc world. (And I think U-Boot will actually fixup the device tree in a similar manner itself these days.) So if there are problems with this, please do tell. Is it cropping the memory nodes or using the reserve map ? Cropping the size of the memory node. That was simplest to do from the cuboot wrapper at the time. If marking it reserved via a reserve map is more elegant and correct, we could do that. But I will still like to know what about the other way is hairy please. josh ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
Cropping the size of the memory node. That was simplest to do from the cuboot wrapper at the time. If marking it reserved via a reserve map is more elegant and correct, we could do that. But I will still like to know what about the other way is hairy please. I don't like it :-) Bad feeling ... don't like having a memory node entry that isn't aligned to some large power of two typically. Cheers, Ben. ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Fri, Oct 31, 2008 at 06:23:28PM -0500, Hollis Blanchard wrote:
On Wed, Oct 22, 2008 at 9:28 AM, Christian Ehrhardt
[EMAIL PROTECTED] wrote:
Hi Ilya,
I just tried your patch on my 440 board because it would help us in our
environment.
Unfortunately I run into a bug on early boot (mark_bootmem).
A log can be found in this mail, this is the bug when running with 64k page
size.
I tried this with and without your 2/2 265k patch and also with page size
configured to 16k, the error is the same in all cases.
I used an earlier version of your patch in the past and it worked fine.
Applying this old patch causes the same problem.
Therefore I expect that there was some other code changed that breaks with
page size != 4k.
This patch seems to solve the problem for me, but I have to run and
haven't yet worked out if it's the right fix.
diff --git a/mm/bootmem.c b/mm/bootmem.c
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -300,7 +300,7 @@ static int __init mark_bootmem(unsigned
unsigned long max;
if (pos bdata-node_min_pfn ||
- pos = bdata-node_low_pfn) {
+ pos bdata-node_low_pfn) {
BUG_ON(pos != start);
continue;
}
@@ -399,7 +399,7 @@ int __init reserve_bootmem(unsigned long
unsigned long start, end;
start = PFN_DOWN(addr);
- end = PFN_UP(addr + size);
+ end = PFN_DOWN(addr + size);
return mark_bootmem(start, end, 1, flags);
}
Looks like the breakage may have been accidentally introduced by
Johannes Weiner [EMAIL PROTECTED] on Jul 24 (post 2.6.26).
FWIW, the boards Christian and I are hitting the problem on are
Sequoias with 256MB of RAM. cuImage is reporting only 0x000 bytes
of RAM though, which may be exacerbating the situation.
That is on purpose. The chip has an errata that causes badness if
you use the last XX bytes of DRAM. I forget exactly what XX is, but
we just remove the last page.
josh
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Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Sat, 2008-11-01 at 07:30 -0400, Josh Boyer wrote: That is on purpose. The chip has an errata that causes badness if you use the last XX bytes of DRAM. I forget exactly what XX is, but we just remove the last page. Doing that from the device-tree is very hairy tho... you end up with informations in there that aren't aligned etc... oh well. Ben. ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Wed, Oct 22, 2008 at 9:28 AM, Christian Ehrhardt
[EMAIL PROTECTED] wrote:
Hi Ilya,
I just tried your patch on my 440 board because it would help us in our
environment.
Unfortunately I run into a bug on early boot (mark_bootmem).
A log can be found in this mail, this is the bug when running with 64k page
size.
I tried this with and without your 2/2 265k patch and also with page size
configured to 16k, the error is the same in all cases.
I used an earlier version of your patch in the past and it worked fine.
Applying this old patch causes the same problem.
Therefore I expect that there was some other code changed that breaks with
page size != 4k.
This patch seems to solve the problem for me, but I have to run and
haven't yet worked out if it's the right fix.
diff --git a/mm/bootmem.c b/mm/bootmem.c
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -300,7 +300,7 @@ static int __init mark_bootmem(unsigned
unsigned long max;
if (pos bdata-node_min_pfn ||
- pos = bdata-node_low_pfn) {
+ pos bdata-node_low_pfn) {
BUG_ON(pos != start);
continue;
}
@@ -399,7 +399,7 @@ int __init reserve_bootmem(unsigned long
unsigned long start, end;
start = PFN_DOWN(addr);
- end = PFN_UP(addr + size);
+ end = PFN_DOWN(addr + size);
return mark_bootmem(start, end, 1, flags);
}
Looks like the breakage may have been accidentally introduced by
Johannes Weiner [EMAIL PROTECTED] on Jul 24 (post 2.6.26).
FWIW, the boards Christian and I are hitting the problem on are
Sequoias with 256MB of RAM. cuImage is reporting only 0x000 bytes
of RAM though, which may be exacerbating the situation.
-Hollis
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Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
Hi Ilya, I just tried your patch on my 440 board because it would help us in our environment. Unfortunately I run into a bug on early boot (mark_bootmem). A log can be found in this mail, this is the bug when running with 64k page size. I tried this with and without your 2/2 265k patch and also with page size configured to 16k, the error is the same in all cases. I used an earlier version of your patch in the past and it worked fine. Applying this old patch causes the same problem. Therefore I expect that there was some other code changed that breaks with page size != 4k. I did not check that in detail yet, but I would be happy for every hint I could get to fix this. = bootm ## Booting kernel from Legacy Image at 0400 ... Image Name: Linux-2.6.27-dirty Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size:1512203 Bytes = 1.4 MB Load Address: 0040 Entry Point: 00400458 Verifying Checksum ... OK Uncompressing Kernel Image ... OK CPU clock-frequency - 0x27bc86a4 (667MHz) CPU timebase-frequency - 0x27bc86a4 (667MHz) /plb: clock-frequency - 9ef21a9 (167MHz) /plb/opb: clock-frequency - 4f790d4 (83MHz) /plb/opb/ebc: clock-frequency - 34fb5e3 (56MHz) /plb/opb/[EMAIL PROTECTED]: clock-frequency - a8c000 (11MHz) /plb/opb/[EMAIL PROTECTED]: clock-frequency - a8c000 (11MHz) /plb/opb/[EMAIL PROTECTED]: clock-frequency - 42ecac (4MHz) /plb/opb/[EMAIL PROTECTED]: clock-frequency - 42ecac (4MHz) Memory - 0x0 0x0 0x000 (255MB) ethernet0: local-mac-address - 00:10:ec:00:e2:3e ethernet1: local-mac-address - 00:10:ec:80:e2:3e zImage starting: loaded at 0x0040 (sp: 0x0fe3c820) Allocating 0x3c54dc bytes for kernel ... gunzipping (0x - 0x0040e000:0x007a2428)...done 0x380a90 bytes Linux/PowerPC load: console=ttyS0,115200 ip=dhcp nfsroot=192.168.1.2:/home/paelzer/ubuntu_ppc.8.04 root=/dev/nfs rw Finalizing device tree... flat tree at 0x40bed8 Using PowerPC 44x Platform machine description Linux version 2.6.27-dirty ([EMAIL PROTECTED]) (gcc version 4.2.3) #5 Wed Oct 22 15:15:40 CEST 2008 console [udbg0] enabled [ cut here ] Kernel BUG at c02be6cc [verbose debug info unavailable] Oops: Exception in kernel mode, sig: 5 [#1] PowerPC 44x Platform NIP: c02be6cc LR: c02ba4e4 CTR: REGS: c0351eb0 TRAP: 0700 Not tainted (2.6.27-dirty) MSR: 00021000 ME CR: 22004022 XER: 005f TASK = c03204a8[0] 'swapper' THREAD: c035 GPR00: c02d0a1c c0351f60 c03204a8 0fff 1000 0001 GPR08: e000 c02d0a14 2224 0ffa6800 0ffbf000 GPR16: c02ed838 bfe8f45c 0ffa7500 0fe3cb20 0001 c02d0a1c GPR24: 0001 1000 0fff c039 0fff c039d1d0 c02d0a08 NIP [c02be6cc] mark_bootmem+0xe0/0x124 LR [c02ba4e4] do_init_bootmem+0x134/0x168 Call Trace: [c0351f60] [c02be6a4] mark_bootmem+0xb8/0x124 (unreliable) [c0351f90] [c02ba4e4] do_init_bootmem+0x134/0x168 [c0351fb0] [c02b8e00] setup_arch+0x13c/0x1b8 [c0351fc0] [c02b066c] start_kernel+0x94/0x2ac [c0351ff0] [c1e8] skpinv+0x190/0x1cc Instruction dump: 7f07c378 4bfffe15 7c7e1b78 4192000c 2f83 409e0024 7f9ae000 419e0050 817f0014 83bf0004 3bebffec 4b68 0fe0 4800 7f63db78 7fa4eb78 ---[ end trace 31fd0ba7d8756001 ]--- Kernel panic - not syncing: Attempted to kill the idle task! Rebooting in 180 seconds.. Ilya Yanok wrote: This patch adds support for page sizes bigger than 4K (16K/64K) on PPC 44x. Signed-off-by: Yuri Tikhonov [EMAIL PROTECTED] Signed-off-by: Vladimir Panfilov [EMAIL PROTECTED] Signed-off-by: Ilya Yanok [EMAIL PROTECTED] --- arch/powerpc/Kconfig | 26 -- arch/powerpc/include/asm/highmem.h |8 +++- arch/powerpc/include/asm/mmu-44x.h | 18 ++ arch/powerpc/include/asm/page.h| 13 - arch/powerpc/include/asm/pgtable.h |3 +++ arch/powerpc/kernel/asm-offsets.c |4 arch/powerpc/kernel/head_44x.S | 22 +- arch/powerpc/kernel/misc_32.S | 12 ++-- arch/powerpc/mm/pgtable_32.c |9 ++--- arch/powerpc/platforms/Kconfig.cputype |2 +- 10 files changed, 82 insertions(+), 35 deletions(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 587da5e..9627cfd 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -402,16 +402,30 @@ config PPC_HAS_HASH_64K depends on PPC64 default n -config PPC_64K_PAGES - bool 64k page size - depends on PPC64 - select PPC_HAS_HASH_64K +choice + prompt Page size + default PPC_4K_PAGES help - This option changes the kernel logical page size to 64k. On machines + The PAGE_SIZE definition. Increasing the page size may + improve the system performance in some dedicated cases like software + RAID with accelerated calculations. In PPC64 case on machines
Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
Ilya, here the snippet you asked for with CONFIG_DEBUG_BUGVERBOSE enabled and bootmem_debug set. ## Booting kernel from Legacy Image at 0400 ... Image Name: Linux-2.6.27-dirty Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size:1521505 Bytes = 1.5 MB Load Address: 0040 Entry Point: 00400458 Verifying Checksum ... OK Uncompressing Kernel Image ... OK CPU clock-frequency - 0x27bc86a4 (667MHz) CPU timebase-frequency - 0x27bc86a4 (667MHz) /plb: clock-frequency - 9ef21a9 (167MHz) /plb/opb: clock-frequency - 4f790d4 (83MHz) /plb/opb/ebc: clock-frequency - 34fb5e3 (56MHz) /plb/opb/[EMAIL PROTECTED]: clock-frequency - a8c000 (11MHz) /plb/opb/[EMAIL PROTECTED]: clock-frequency - a8c000 (11MHz) /plb/opb/[EMAIL PROTECTED]: clock-frequency - 42ecac (4MHz) /plb/opb/[EMAIL PROTECTED]: clock-frequency - 42ecac (4MHz) Memory - 0x0 0x0 0x000 (255MB) ethernet0: local-mac-address - 00:10:ec:00:e2:3e ethernet1: local-mac-address - 00:10:ec:80:e2:3e zImage starting: loaded at 0x0040 (sp: 0x0fe3c820) Allocating 0x3d54dc bytes for kernel ... gunzipping (0x - 0x0040e000:0x007b24a4)...done 0x390af8 bytes Linux/PowerPC load: console=ttyS0,115200 ip=dhcp nfsroot=192.168.1.2:/home/paelzer/ubuntu_ppc.8.04 root=/dev/nfs rw bootmem_debug Finalizing device tree... flat tree at 0x40bed8 Using PowerPC 44x Platform machine description Linux version 2.6.27-dirty ([EMAIL PROTECTED]) (gcc version 4.2.3) #12 Wed Oct 22 19:40:49 CEST 2008 console [udbg0] enabled bootmem::init_bootmem_core nid=0 start=0 map=ffd end=fff mapsize=200 bootmem::mark_bootmem_node nid=0 start=0 end=fff reserve=0 flags=0 bootmem::__free nid=0 start=0 end=fff bootmem::mark_bootmem_node nid=0 start=0 end=3e reserve=1 flags=0 bootmem::__reserve nid=0 start=0 end=3e flags=0 bootmem::mark_bootmem_node nid=0 start=40 end=41 reserve=1 flags=0 bootmem::__reserve nid=0 start=40 end=41 flags=0 bootmem::mark_bootmem_node nid=0 start=ffd end=fff reserve=1 flags=0 bootmem::__reserve nid=0 start=ffd end=fff flags=0 [ cut here ] kernel BUG at mm/bootmem.c:320! Oops: Exception in kernel mode, sig: 5 [#1] PowerPC 44x Platform NIP: c02ce838 LR: c02ca4e4 CTR: c000dcf8 REGS: c0361eb0 TRAP: 0700 Not tainted (2.6.27-dirty) MSR: 00021000 ME CR: 22004022 XER: 005f TASK = c03304a8[0] 'swapper' THREAD: c036 GPR00: c02e0c98 c0361f60 c03304a8 0fff 1000 0001 4000 GPR08: e000 c02e0c90 2224 0ffa6800 0ffbf000 GPR16: 100c 100c 0ffa7500 0fe3cb20 0001 c02e0c98 GPR24: 0001 1000 0fff c03a 0fff c03ad1e0 c02e0c84 NIP [c02ce838] mark_bootmem+0xe0/0x124 LR [c02ca4e4] do_init_bootmem+0x134/0x168 Call Trace: [c0361f60] [c02ce810] mark_bootmem+0xb8/0x124 (unreliable) [c0361f90] [c02ca4e4] do_init_bootmem+0x134/0x168 [c0361fb0] [c02c8e00] setup_arch+0x13c/0x1b8 [c0361fc0] [c02c066c] start_kernel+0x94/0x2ac [c0361ff0] [c1e8] skpinv+0x190/0x1cc Instruction dump: 7f07c378 4bfffe15 7c7e1b78 4192000c 2f83 409e0024 7f9ae000 419e0050 817f0014 83bf0004 3bebffec 4b68 0fe0 4800 7f63db78 7fa4eb78 ---[ end trace 31fd0ba7d8756001 ]--- Kernel panic - not syncing: Attempted to kill the idle task! Rebooting in 180 seconds.. Christian Ehrhardt wrote: Hi Ilya, I just tried your patch on my 440 board because it would help us in our environment. Unfortunately I run into a bug on early boot (mark_bootmem). A log can be found in this mail, this is the bug when running with 64k page size. I tried this with and without your 2/2 265k patch and also with page size configured to 16k, the error is the same in all cases. I used an earlier version of your patch in the past and it worked fine. Applying this old patch causes the same problem. Therefore I expect that there was some other code changed that breaks with page size != 4k. I did not check that in detail yet, but I would be happy for every hint I could get to fix this. = bootm ## Booting kernel from Legacy Image at 0400 ... Image Name: Linux-2.6.27-dirty Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size:1512203 Bytes = 1.4 MB Load Address: 0040 Entry Point: 00400458 Verifying Checksum ... OK Uncompressing Kernel Image ... OK CPU clock-frequency - 0x27bc86a4 (667MHz) CPU timebase-frequency - 0x27bc86a4 (667MHz) /plb: clock-frequency - 9ef21a9 (167MHz) /plb/opb: clock-frequency - 4f790d4 (83MHz) /plb/opb/ebc: clock-frequency - 34fb5e3 (56MHz) /plb/opb/[EMAIL PROTECTED]: clock-frequency - a8c000 (11MHz) /plb/opb/[EMAIL PROTECTED]: clock-frequency - a8c000 (11MHz) /plb/opb/[EMAIL PROTECTED]: clock-frequency - 42ecac (4MHz) /plb/opb/[EMAIL PROTECTED]: clock-frequency - 42ecac (4MHz) Memory - 0x0 0x0 0x000 (255MB) ethernet0: local-mac-address - 00:10:ec:00:e2:3e ethernet1: local-mac-address - 00:10:ec:80:e2:3e zImage starting: loaded at 0x0040 (sp: 0x0fe3c820) Allocating
Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Fri, 17 Oct 2008 08:54:52 -0700 prodyut hazarika [EMAIL PROTECTED] wrote: On Wed, Oct 15, 2008 at 7:22 PM, Ilya Yanok [EMAIL PROTECTED] wrote: This patch adds support for page sizes bigger than 4K (16K/64K) on PPC 44x. This patch looks good to me. Seems that all the review comments have been incorporated. Josh, it would be great if this patch is pulled into the mainline kernel. I have seen significant performance improvement with RAID0/5 by using 64K pages. It helps if you CC the person you're writing too :). Anyway, I looked over it briefly and agree it looks pretty good. A bit late for 2.6.28, but I'll do a more thorough review and get it in for 2.6.29. josh ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
It helps if you CC the person you're writing too :). Thanks Josh for pointing this out :-) I will be careful in future. Anyway, I looked over it briefly and agree it looks pretty good. A bit late for 2.6.28, but I'll do a more thorough review and get it in for 2.6.29. Great. Look forward to seeing this on the mainline kernel. ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
On Wed, Oct 15, 2008 at 7:22 PM, Ilya Yanok [EMAIL PROTECTED] wrote: This patch adds support for page sizes bigger than 4K (16K/64K) on PPC 44x. This patch looks good to me. Seems that all the review comments have been incorporated. Josh, it would be great if this patch is pulled into the mainline kernel. I have seen significant performance improvement with RAID0/5 by using 64K pages. ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
[PATCH 1/2] powerpc: add 16K/64K pages support for the 44x PPC32 architectures.
This patch adds support for page sizes bigger than 4K (16K/64K) on
PPC 44x.
Signed-off-by: Yuri Tikhonov [EMAIL PROTECTED]
Signed-off-by: Vladimir Panfilov [EMAIL PROTECTED]
Signed-off-by: Ilya Yanok [EMAIL PROTECTED]
---
arch/powerpc/Kconfig | 26 --
arch/powerpc/include/asm/highmem.h |8 +++-
arch/powerpc/include/asm/mmu-44x.h | 18 ++
arch/powerpc/include/asm/page.h| 13 -
arch/powerpc/include/asm/pgtable.h |3 +++
arch/powerpc/kernel/asm-offsets.c |4
arch/powerpc/kernel/head_44x.S | 22 +-
arch/powerpc/kernel/misc_32.S | 12 ++--
arch/powerpc/mm/pgtable_32.c |9 ++---
arch/powerpc/platforms/Kconfig.cputype |2 +-
10 files changed, 82 insertions(+), 35 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 587da5e..9627cfd 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -402,16 +402,30 @@ config PPC_HAS_HASH_64K
depends on PPC64
default n
-config PPC_64K_PAGES
- bool 64k page size
- depends on PPC64
- select PPC_HAS_HASH_64K
+choice
+ prompt Page size
+ default PPC_4K_PAGES
help
- This option changes the kernel logical page size to 64k. On machines
+ The PAGE_SIZE definition. Increasing the page size may
+ improve the system performance in some dedicated cases like software
+ RAID with accelerated calculations. In PPC64 case on machines
without processor support for 64k pages, the kernel will simulate
them by loading each individual 4k page on demand transparently,
while on hardware with such support, it will be used to map
normal application pages.
+ If unsure, set it to 4 KB.
+
+config PPC_4K_PAGES
+ bool 4k page size
+
+config PPC_16K_PAGES
+ bool 16k page size if 44x
+
+config PPC_64K_PAGES
+ bool 64k page size if 44x || PPC64
+ select PPC_HAS_HASH_64K if PPC64
+
+endchoice
config FORCE_MAX_ZONEORDER
int Maximum zone order
@@ -435,7 +449,7 @@ config FORCE_MAX_ZONEORDER
config PPC_SUBPAGE_PROT
bool Support setting protections for 4k subpages
- depends on PPC_64K_PAGES
+ depends on PPC64 PPC_64K_PAGES
help
This option adds support for a system call to allow user programs
to set access permissions (read/write, readonly, or no access)
diff --git a/arch/powerpc/include/asm/highmem.h
b/arch/powerpc/include/asm/highmem.h
index 5d99b64..dc1132c 100644
--- a/arch/powerpc/include/asm/highmem.h
+++ b/arch/powerpc/include/asm/highmem.h
@@ -38,9 +38,15 @@ extern pte_t *pkmap_page_table;
* easily, subsequent pte tables have to be allocated in one physical
* chunk of RAM.
*/
+#if defined(CONFIG_PPC_64K_PAGES) !defined(CONFIG_PPC64)
+#define PKMAP_ORDER(27 - PAGE_SHIFT)
+#define LAST_PKMAP (1 PKMAP_ORDER)
+#define PKMAP_BASE (FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1))
+#else
#define LAST_PKMAP (1 PTE_SHIFT)
-#define LAST_PKMAP_MASK (LAST_PKMAP-1)
#define PKMAP_BASE ((FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1))
PMD_MASK)
+#endif
+#define LAST_PKMAP_MASK(LAST_PKMAP-1)
#define PKMAP_NR(virt) ((virt-PKMAP_BASE) PAGE_SHIFT)
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) PAGE_SHIFT))
diff --git a/arch/powerpc/include/asm/mmu-44x.h
b/arch/powerpc/include/asm/mmu-44x.h
index a825524..2ca18e8 100644
--- a/arch/powerpc/include/asm/mmu-44x.h
+++ b/arch/powerpc/include/asm/mmu-44x.h
@@ -4,6 +4,8 @@
* PPC440 support
*/
+#include asm/page.h
+
#define PPC44x_MMUCR_TID 0x00ff
#define PPC44x_MMUCR_STS 0x0001
@@ -73,4 +75,20 @@ typedef struct {
/* Size of the TLBs used for pinning in lowmem */
#define PPC_PIN_SIZE (1 28) /* 256M */
+#if (PAGE_SHIFT == 12)
+#define PPC44x_TLBE_SIZE PPC44x_TLB_4K
+#elif (PAGE_SHIFT == 14)
+#define PPC44x_TLBE_SIZE PPC44x_TLB_16K
+#elif (PAGE_SHIFT == 16)
+#define PPC44x_TLBE_SIZE PPC44x_TLB_64K
+#else
+#error Unsupported PAGE_SIZE
+#endif
+
+#define PPC44x_PGD_OFF_SHIFT (32 - PMD_SHIFT + 2)
+#define PPC44x_PGD_OFF_MASK(PMD_SHIFT - 2)
+#define PPC44x_PTE_ADD_SHIFT (32 - PMD_SHIFT + PTE_SHIFT + 3)
+#define PPC44x_PTE_ADD_MASK(32 - 3 - PTE_SHIFT)
+#define PPC44x_RPN_MASK(31 - PAGE_SHIFT)
+
#endif /* _ASM_POWERPC_MMU_44X_H_ */
diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index e088545..537d5b1 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -15,12 +15,15 @@
#include asm/types.h
/*
- * On PPC32 page size is 4K. For PPC64 we support either 4K or 64K software
+ * On regular PPC32 page size is 4K (but we support 4K/16K/64K pages
+ * on PPC44x). For PPC64 we support either 4K or 64K software
* page size. When using 64K pages however, whether we are
