Re: [PATCH 2/6] Introduce CONFIG_ZONE_DMA

Christoph Lameter
2006-09-18T22:58:52Z

On Tue, 19 Sep 2006, Paul Mundt wrote:

> You've missed the other ZONE_DMA references, if you scroll a bit further
> down that's where we fill in ZONE_DMA, this is simply the default zone
> layout that we rely on for nommu.

Are you sure that sh does not need ZONE_DMA? There is code in there
to check for the DMA boundary. The following patch disables that
code if CONFIG_ZONE_DMA is not set.

sh / sh64: Remove ZONE_DMA remains.

Both arches do not need ZONE_DMA

Signed-off-by: Christoph Lameter <clameter@sgi.com>

Index: linux-2.6.18-rc6-mm2/arch/sh/mm/init.c
=================================--- linux-2.6.18-rc6-mm2.orig/arch/sh/mm/init.c 2006-09-18 13:27:48.125691412 -0500
+++ linux-2.6.18-rc6-mm2/arch/sh/mm/init.c 2006-09-18 17:56:23.632421140 -0500
@@ -156,7 +156,6 @@ void __init paging_init(void)
* Setup some defaults for the zone sizes.. these should be safe
* regardless of distcontiguous memory or MMU settings.
*/
- zones_size[ZONE_DMA] = 0 >> PAGE_SHIFT;
zones_size[ZONE_NORMAL] = __MEMORY_SIZE >> PAGE_SHIFT;
#ifdef CONFIG_HIGHMEM
zones_size[ZONE_HIGHMEM] = 0 >> PAGE_SHIFT;
@@ -186,13 +185,16 @@ void __init paging_init(void)
max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
low = MAX_LOW_PFN;

- if (low < max_dma) {
- zones_size[ZONE_DMA] = low - start_pfn;
- zones_size[ZONE_NORMAL] = 0;
- } else {
+#ifdef CONFIG_ZONE_DMA
+ if (low < max_dma)
+#endif
+ zones_size[ZONE_NORMAL] = low - start_pfn;
+#ifdef CONFIG_ZONE_DMA
+ else {
zones_size[ZONE_DMA] = max_dma - start_pfn;
zones_size[ZONE_NORMAL] = low - max_dma;
}
+#endif
}

#elif defined(CONFIG_CPU_SH3) || defined(CONFIG_CPU_SH4)
Index: linux-2.6.18-rc6-mm2/arch/sh64/mm/init.c
=================================--- linux-2.6.18-rc6-mm2.orig/arch/sh64/mm/init.c 2006-09-18 13:27:48.134481203 -0500
+++ linux-2.6.18-rc6-mm2/arch/sh64/mm/init.c 2006-09-18 17:54:14.263532486 -0500
@@ -118,10 +118,7 @@ void __init paging_init(void)

mmu_context_cache = MMU_CONTEXT_FIRST_VERSION;

- /*
- * All memory is good as ZONE_NORMAL (fall-through) and ZONE_DMA.
- */
- zones_size[ZONE_DMA] = MAX_LOW_PFN - START_PFN;
+ zones_size[ZONE_NORMAL] = MAX_LOW_PFN - START_PFN;
NODE_DATA(0)->node_mem_map = NULL;
free_area_init_node(0, NODE_DATA(0), zones_size, __MEMORY_START >> PAGE_SHIFT, 0);
}
Index: linux-2.6.18-rc6-mm2/arch/sh64/Kconfig
=================================--- linux-2.6.18-rc6-mm2.orig/arch/sh64/Kconfig 2006-09-18 13:27:48.145224281 -0500
+++ linux-2.6.18-rc6-mm2/arch/sh64/Kconfig 2006-09-18 17:54:14.285995416 -0500
@@ -36,9 +36,6 @@ config GENERIC_CALIBRATE_DELAY
config RWSEM_XCHGADD_ALGORITHM
bool

-config GENERIC_ISA_DMA
- bool
-
source init/Kconfig

menu "System type"