From 37ba7ab5e33cebc25c68fffe33e9f21e7c2014e8 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Mon, 11 May 2009 15:56:08 -0700 Subject: x86, boot: make kernel_alignment adjustable; new bzImage fields Make the kernel_alignment field adjustable; this allows us to set it to a large value (intended to be 16 MB to avoid ZONE_DMA contention, memory holes and other weirdness) while a smart bootloader can still force a loading at a lesser alignment if absolutely necessary. Also export pref_address (preferred loading address, corresponding to the link-time address) and init_size, the total amount of linear memory the kernel will require during initialization. [ Impact: allows better kernel placement, gives bootloader more info ] Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/boot.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'arch/x86/include/asm/boot.h') diff --git a/arch/x86/include/asm/boot.h b/arch/x86/include/asm/boot.h index 6ba23dd9fc9..418e632d4a8 100644 --- a/arch/x86/include/asm/boot.h +++ b/arch/x86/include/asm/boot.h @@ -8,11 +8,26 @@ #ifdef __KERNEL__ +#include + /* Physical address where kernel should be loaded. */ #define LOAD_PHYSICAL_ADDR ((CONFIG_PHYSICAL_START \ + (CONFIG_PHYSICAL_ALIGN - 1)) \ & ~(CONFIG_PHYSICAL_ALIGN - 1)) +/* Minimum kernel alignment, as a power of two */ +#ifdef CONFIG_x86_64 +#define MIN_KERNEL_ALIGN_LG2 PMD_SHIFT +#else +#define MIN_KERNEL_ALIGN_LG2 (PAGE_SHIFT+1) +#endif +#define MIN_KERNEL_ALIGN (_AC(1, UL) << MIN_KERNEL_ALIGN_LG2) + +#if (CONFIG_PHYSICAL_ALIGN & (CONFIG_PHYSICAL_ALIGN-1)) || \ + (CONFIG_PHYSICAL_ALIGN < (_AC(1, UL) << MIN_KERNEL_ALIGN_LG2)) +#error "Invalid value for CONFIG_PHYSICAL_ALIGN" +#endif + #ifdef CONFIG_KERNEL_BZIP2 #define BOOT_HEAP_SIZE 0x400000 #else /* !CONFIG_KERNEL_BZIP2 */ -- cgit v1.2.3