[POWERPC] Introduce lowmem_end_addr to distinguish from total_lowmem

total_lowmem represents the amount of low memory, not the physical
address that low memory ends at.  If the start of memory is at 0 it
happens that total_lowmem can be used as both the size and the address
that lowmem ends at (or more specifically one byte beyond the end).

To make the code a bit more clear and deal with the case when the start of
memory isn't at physical 0, we introduce lowmem_end_addr that represents
one byte beyond the last physical address in the lowmem region.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Kumar Gala 2008-04-16 05:52:22 +10:00 committed by Paul Mackerras
parent 99c62dd773
commit d7917ba705
5 changed files with 16 additions and 9 deletions

View file

@ -67,7 +67,7 @@ unsigned long __init mmu_mapin_ram(void)
/* Pin in enough TLBs to cover any lowmem not covered by the
* initial 256M mapping established in head_44x.S */
for (addr = PPC_PIN_SIZE; addr < total_lowmem;
for (addr = PPC_PIN_SIZE; addr < lowmem_end_addr;
addr += PPC_PIN_SIZE)
ppc44x_pin_tlb(addr + PAGE_OFFSET, addr);

View file

@ -146,6 +146,7 @@ void __init MMU_init(void)
}
total_lowmem = total_memory = lmb_end_of_DRAM() - memstart_addr;
lowmem_end_addr = memstart_addr + total_lowmem;
#ifdef CONFIG_FSL_BOOKE
/* Freescale Book-E parts expect lowmem to be mapped by fixed TLB
@ -156,9 +157,10 @@ void __init MMU_init(void)
if (total_lowmem > __max_low_memory) {
total_lowmem = __max_low_memory;
lowmem_end_addr = memstart_addr + total_lowmem;
#ifndef CONFIG_HIGHMEM
total_memory = total_lowmem;
lmb_enforce_memory_limit(total_lowmem);
lmb_enforce_memory_limit(lowmem_end_addr);
lmb_analyze();
#endif /* CONFIG_HIGHMEM */
}

View file

@ -75,6 +75,8 @@
/* max amount of RAM to use */
unsigned long __max_memory;
phys_addr_t memstart_addr;
void free_initmem(void)
{
unsigned long addr;

View file

@ -216,9 +216,11 @@ void __init do_init_bootmem(void)
unsigned long total_pages;
int boot_mapsize;
max_pfn = total_pages = lmb_end_of_DRAM() >> PAGE_SHIFT;
max_pfn = lmb_end_of_DRAM() >> PAGE_SHIFT;
total_pages = (lmb_end_of_DRAM() - memstart_addr) >> PAGE_SHIFT;
#ifdef CONFIG_HIGHMEM
total_pages = total_lowmem >> PAGE_SHIFT;
max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
#endif
/*
@ -244,18 +246,18 @@ void __init do_init_bootmem(void)
* present.
*/
#ifdef CONFIG_HIGHMEM
free_bootmem_with_active_regions(0, total_lowmem >> PAGE_SHIFT);
free_bootmem_with_active_regions(0, lowmem_end_addr >> PAGE_SHIFT);
/* reserve the sections we're already using */
for (i = 0; i < lmb.reserved.cnt; i++) {
unsigned long addr = lmb.reserved.region[i].base +
lmb_size_bytes(&lmb.reserved, i) - 1;
if (addr < total_lowmem)
if (addr < lowmem_end_addr)
reserve_bootmem(lmb.reserved.region[i].base,
lmb_size_bytes(&lmb.reserved, i),
BOOTMEM_DEFAULT);
else if (lmb.reserved.region[i].base < total_lowmem) {
unsigned long adjusted_size = total_lowmem -
else if (lmb.reserved.region[i].base < lowmem_end_addr) {
unsigned long adjusted_size = lowmem_end_addr -
lmb.reserved.region[i].base;
reserve_bootmem(lmb.reserved.region[i].base,
adjusted_size, BOOTMEM_DEFAULT);
@ -325,7 +327,7 @@ void __init paging_init(void)
(top_of_ram - total_ram) >> 20);
memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
#ifdef CONFIG_HIGHMEM
max_zone_pfns[ZONE_DMA] = total_lowmem >> PAGE_SHIFT;
max_zone_pfns[ZONE_DMA] = lowmem_end_addr >> PAGE_SHIFT;
max_zone_pfns[ZONE_HIGHMEM] = top_of_ram >> PAGE_SHIFT;
#else
max_zone_pfns[ZONE_DMA] = top_of_ram >> PAGE_SHIFT;
@ -380,7 +382,7 @@ void __init mem_init(void)
{
unsigned long pfn, highmem_mapnr;
highmem_mapnr = total_lowmem >> PAGE_SHIFT;
highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
struct page *page = pfn_to_page(pfn);
if (lmb_is_reserved(pfn << PAGE_SHIFT))

View file

@ -52,6 +52,7 @@ extern unsigned long __initial_memory_limit;
extern unsigned long total_memory;
extern unsigned long total_lowmem;
extern phys_addr_t memstart_addr;
extern phys_addr_t lowmem_end_addr;
/* ...and now those things that may be slightly different between processor
* architectures. -- Dan