From 486df8bc4627bdfc032d11bedcd056cc5343ee62 Mon Sep 17 00:00:00 2001 From: Andreas Schwab Date: Thu, 24 Apr 2014 12:24:48 +0200 Subject: [PATCH] m68k: Increase initial mapping to 8 or 16 MiB if possible If the size of the first memory chunk is at least 8 or 16 MiB increase the initial mapping to 8 resp. 16 MiB instead of 4 MiB. This makes it possible to 1. Map more memory in the first node without running out of space for the page tables, 2. Boot kernels that don't fit in 4 MiB (e.g. multi_defconfig). Signed-off-by: Andreas Schwab - Add support for 8 MiB, - Store initial mapping size in head.S for later reuse, - Add comment about large kernels. Signed-off-by: Geert Uytterhoeven --- arch/m68k/kernel/head.S | 19 +++++++++++++++++-- arch/m68k/mm/motorola.c | 10 ++++++---- 2 files changed, 23 insertions(+), 6 deletions(-) diff --git a/arch/m68k/kernel/head.S b/arch/m68k/kernel/head.S index 15c8f55e4835..dbb118e1a4e0 100644 --- a/arch/m68k/kernel/head.S +++ b/arch/m68k/kernel/head.S @@ -292,6 +292,7 @@ .globl kernel_pg_dir .globl availmem +.globl m68k_init_mapped_size .globl m68k_pgtable_cachemode .globl m68k_supervisor_cachemode #ifdef CONFIG_MVME16x @@ -907,10 +908,21 @@ L(nocon): * * This block of code does what's necessary to map in the various kinds * of machines for execution of Linux. - * First map the first 4 MB of kernel code & data + * First map the first 4, 8, or 16 MB of kernel code & data */ - mmu_map #PAGE_OFFSET,%pc@(L(phys_kernel_start)),#4*1024*1024,\ + get_bi_record BI_MEMCHUNK + movel %a0@(4),%d0 + movel #16*1024*1024,%d1 + cmpl %d0,%d1 + jls 1f + lsrl #1,%d1 + cmpl %d0,%d1 + jls 1f + lsrl #1,%d1 +1: + movel %d1,m68k_init_mapped_size + mmu_map #PAGE_OFFSET,%pc@(L(phys_kernel_start)),%d1,\ %pc@(m68k_supervisor_cachemode) putc 'C' @@ -3730,6 +3742,9 @@ func_return console_plot_pixel __INITDATA .align 4 +m68k_init_mapped_size: + .long 0 + #if defined(CONFIG_ATARI) || defined(CONFIG_AMIGA) || \ defined(CONFIG_HP300) || defined(CONFIG_APOLLO) L(custom): diff --git a/arch/m68k/mm/motorola.c b/arch/m68k/mm/motorola.c index 7d4024432163..b958916e5eac 100644 --- a/arch/m68k/mm/motorola.c +++ b/arch/m68k/mm/motorola.c @@ -45,7 +45,7 @@ EXPORT_SYMBOL(mm_cachebits); #endif /* size of memory already mapped in head.S */ -#define INIT_MAPPED_SIZE (4UL<<20) +extern __initdata unsigned long m68k_init_mapped_size; extern unsigned long availmem; @@ -271,10 +271,12 @@ void __init paging_init(void) */ addr = m68k_memory[0].addr; size = m68k_memory[0].size; - free_bootmem_node(NODE_DATA(0), availmem, min(INIT_MAPPED_SIZE, size) - (availmem - addr)); + free_bootmem_node(NODE_DATA(0), availmem, + min(m68k_init_mapped_size, size) - (availmem - addr)); map_node(0); - if (size > INIT_MAPPED_SIZE) - free_bootmem_node(NODE_DATA(0), addr + INIT_MAPPED_SIZE, size - INIT_MAPPED_SIZE); + if (size > m68k_init_mapped_size) + free_bootmem_node(NODE_DATA(0), addr + m68k_init_mapped_size, + size - m68k_init_mapped_size); for (i = 1; i < m68k_num_memory; i++) map_node(i); -- 2.20.1