The current CHIP11 errata truncates the device tree memory node, and subtracts
(hardcoded) 4096 bytes. This breaks kernels with larger PAGE_SIZE, since the
bootmem allocator assumes that total memory is a multiple of 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]>
---
Changes from v2:
- David pointed out I'd duplicated the fdt_add_mem_rsv() prototype, and that
4xx.c should directly include libfdt/libfdt.h instead.
Using large pages results in a huge performance improvement for KVM, and this
patch is required to make Ilya's large page patch work. David and/or Josh,
please apply.
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
@@ -20,8 +20,9 @@
#include "ops.h"
#include "reg.h"
#include "dcr.h"
+#include "libfdt/libfdt.h"
-static unsigned long chip_11_errata(unsigned long memsize)
+static void chip_11_errata(unsigned long memsize)
{
unsigned long pvr;
@@ -31,13 +32,11 @@ static unsigned long chip_11_errata(unsi
case 0x40000850:
case 0x400008d0:
case 0x200008d0:
- memsize -= 4096;
+ fdt_add_mem_rsv(fdt, memsize - 256, 256);
break;
default:
break;
}
-
- return memsize;
}
/* Read the 4xx SDRAM controller to get size of system memory. */
@@ -53,7 +52,7 @@ 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 +218,7 @@ 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
@@ -51,7 +51,7 @@
#define devp_offset_find(devp) (((int)(devp))-1)
#define devp_offset(devp) (devp ? ((int)(devp))-1 : 0)
-static void *fdt;
+void *fdt;
static void *buf; /* = NULL */
#define EXPAND_GRANULARITY 1024
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
@@ -14,6 +14,7 @@
#include <stddef.h>
#include "types.h"
#include "string.h"
+#include "libfdt_env.h"
#define COMMAND_LINE_SIZE 512
#define MAX_PATH_LEN 256
@@ -32,6 +33,9 @@ struct platform_ops {
void * (*vmlinux_alloc)(unsigned long size);
};
extern struct platform_ops platform_ops;
+
+/* The device tree itself. Should almost always be accessed via dt_ops. */
+extern void *fdt;
/* Device Tree operations */
struct dt_ops {
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