From f637a49e507c88354ab32b5d914e06acfb7ee00d Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Wed, 27 May 2009 13:44:50 +1000 Subject: powerpc: Minor cleanups of kernel virt address space definitions Make FIXADDR_TOP a compile time constant and cleanup a couple of definitions relative to the layout of the kernel address space on ppc32. We also print out that layout at boot time for debugging purposes. This is a pre-requisite for properly fixing non-coherent DMA allocactions. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/fixmap.h | 4 ++-- arch/powerpc/include/asm/pgtable-ppc32.h | 22 ++++++++++++++++++++-- 2 files changed, 22 insertions(+), 4 deletions(-) (limited to 'arch/powerpc/include/asm') diff --git a/arch/powerpc/include/asm/fixmap.h b/arch/powerpc/include/asm/fixmap.h index d60fd18f428..f1f4e23a84e 100644 --- a/arch/powerpc/include/asm/fixmap.h +++ b/arch/powerpc/include/asm/fixmap.h @@ -14,8 +14,6 @@ #ifndef _ASM_FIXMAP_H #define _ASM_FIXMAP_H -extern unsigned long FIXADDR_TOP; - #ifndef __ASSEMBLY__ #include #include @@ -24,6 +22,8 @@ extern unsigned long FIXADDR_TOP; #include #endif +#define FIXADDR_TOP ((unsigned long)(-PAGE_SIZE)) + /* * Here we define all the compile-time 'special' virtual * addresses. The point is to have a constant address at diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h b/arch/powerpc/include/asm/pgtable-ppc32.h index ba45c997830..28fe9d4bae3 100644 --- a/arch/powerpc/include/asm/pgtable-ppc32.h +++ b/arch/powerpc/include/asm/pgtable-ppc32.h @@ -10,7 +10,7 @@ extern unsigned long va_to_phys(unsigned long address); extern pte_t *va_to_pte(unsigned long address); -extern unsigned long ioremap_bot, ioremap_base; +extern unsigned long ioremap_bot; #ifdef CONFIG_44x extern int icache_44x_need_flush; @@ -55,9 +55,27 @@ extern int icache_44x_need_flush; #define pgd_ERROR(e) \ printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e)) +/* + * This is the bottom of the PKMAP area with HIGHMEM or an arbitrary + * value (for now) on others, from where we can start layout kernel + * virtual space that goes below PKMAP and FIXMAP + */ +#ifdef CONFIG_HIGHMEM +#define KVIRT_TOP PKMAP_BASE +#else +#define KVIRT_TOP (0xfe000000UL) /* for now, could be FIXMAP_BASE ? */ +#endif + +/* + * ioremap_bot starts at that address. Early ioremaps move down from there, + * until mem_init() at which point this becomes the top of the vmalloc + * and ioremap space + */ +#define IOREMAP_TOP KVIRT_TOP + /* * Just any arbitrary offset to the start of the vmalloc VM area: the - * current 64MB value just means that there will be a 64MB "hole" after the + * current 16MB value just means that there will be a 64MB "hole" after the * physical memory until the kernel virtual memory starts. That means that * any out-of-bounds memory accesses will hopefully be caught. * The vmalloc() routines leaves a hole of 4kB between each vmalloced -- cgit v1.2.3