From: Franck Bui-Huu <fbuihuu@xxxxxxxxx>
The old code was assuming that min_low_pfn was always 0. This
means that we can't handle platforms with a big hole at start
of memory since mem_map[] size would blew up.
This patch does not relax this constraint but it's a first
step to achieve that.
Signed-off-by: Franck Bui-Huu <fbuihuu@xxxxxxxxx>
---
arch/mips/kernel/setup.c | 27 +++++++++++++++++++--------
arch/mips/mm/init.c | 15 ++++++---------
include/asm-mips/dma.h | 1 +
3 files changed, 26 insertions(+), 17 deletions(-)
diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 89440a0..8e58d7f 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -271,7 +271,6 @@ static void __init bootmem_init(void)
static void __init bootmem_init(void)
{
unsigned long reserved_end;
- unsigned long highest = 0;
unsigned long mapstart = -1UL;
unsigned long bootmap_size;
int i;
@@ -284,6 +283,13 @@ static void __init bootmem_init(void)
reserved_end = max(init_initrd(), PFN_UP(__pa_symbol(&_end)));
/*
+ * max_low_pfn is not a number of pages. The number of pages
+ * of the system is given by 'max_low_pfn - min_low_pfn'.
+ */
+ min_low_pfn = -1UL;
+ max_low_pfn = 0;
+
+ /*
* Find the highest page frame number we have available.
*/
for (i = 0; i < boot_mem_map.nr_map; i++) {
@@ -296,8 +302,10 @@ static void __init bootmem_init(void)
end = PFN_DOWN(boot_mem_map.map[i].addr
+ boot_mem_map.map[i].size);
- if (end > highest)
- highest = end;
+ if (end > max_low_pfn)
+ max_low_pfn = end;
+ if (start < min_low_pfn)
+ min_low_pfn = start;
if (end <= reserved_end)
continue;
if (start >= mapstart)
@@ -305,22 +313,25 @@ static void __init bootmem_init(void)
mapstart = max(reserved_end, start);
}
+ if (min_low_pfn >= max_low_pfn)
+ panic("Boggus memory mapping !!!");
+
/*
* Determine low and high memory ranges
*/
- if (highest > PFN_DOWN(HIGHMEM_START)) {
+ if (max_low_pfn > PFN_DOWN(HIGHMEM_START)) {
#ifdef CONFIG_HIGHMEM
highstart_pfn = PFN_DOWN(HIGHMEM_START);
- highend_pfn = highest;
+ highend_pfn = max_low_pfn;
#endif
- highest = PFN_DOWN(HIGHMEM_START);
+ max_low_pfn = PFN_DOWN(HIGHMEM_START);
}
/*
* Initialize the boot-time allocator with low memory only.
*/
- bootmap_size = init_bootmem(mapstart, highest);
-
+ bootmap_size = init_bootmem_node(NODE_DATA(0), mapstart,
+ min_low_pfn, max_low_pfn);
/*
* Register fully available low RAM pages with the bootmem allocator.
*/
diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c
index 30245c0..e78a1b1 100644
--- a/arch/mips/mm/init.c
+++ b/arch/mips/mm/init.c
@@ -341,7 +341,6 @@ static int __init page_is_ram(unsigned l
void __init paging_init(void)
{
unsigned long zones_size[MAX_NR_ZONES] = { 0, };
- unsigned long max_dma, low;
#ifndef CONFIG_FLATMEM
unsigned long zholes_size[MAX_NR_ZONES] = { 0, };
unsigned long i, j, pfn;
@@ -354,18 +353,16 @@ void __init paging_init(void)
#endif
kmap_coherent_init();
- max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
- low = max_low_pfn;
-
#ifdef CONFIG_ISA
- if (low < max_dma)
- zones_size[ZONE_DMA] = low;
+ if (max_low_pfn < MAX_DMA_PFN)
+ zones_size[ZONE_DMA] = max_low_pfn;
else {
- zones_size[ZONE_DMA] = max_dma;
- zones_size[ZONE_NORMAL] = low - max_dma;
+ unsigned long start_normal_zone = max(min_low_pfn, MAX_DMA_PFN);
+ zones_size[ZONE_DMA] = MAX_DMA_PFN;
+ zones_size[ZONE_NORMAL] = max_low_pfn - start_normal_zone;
}
#else
- zones_size[ZONE_DMA] = low;
+ zones_size[ZONE_DMA] = max_low_pfn - min_low_pfn;
#endif
#ifdef CONFIG_HIGHMEM
zones_size[ZONE_HIGHMEM] = highend_pfn - highstart_pfn;
diff --git a/include/asm-mips/dma.h b/include/asm-mips/dma.h
index 23f789c..e06ef07 100644
--- a/include/asm-mips/dma.h
+++ b/include/asm-mips/dma.h
@@ -91,6 +91,7 @@
#else
#define MAX_DMA_ADDRESS (PAGE_OFFSET + 0x01000000)
#endif
+#define MAX_DMA_PFN PFN_DOWN(virt_to_phys((void *)MAX_DMA_ADDRESS))
/* 8237 DMA controllers */
#define IO_DMA1_BASE 0x00 /* 8 bit slave DMA, channels 0..3 */
--
1.4.4.1
