[PATCH 08/28] m68k: introduce arch_zone_limits_init()

Mike Rapoport
2025-12-28T12:42:19Z

Since all variants of m68k add all memory to ZONE_DMA, it is possible to
use unified implementation for arch_zone_limits_init() that sets the end
of ZONE_DMA to memblock_end_of_DRAM().

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
---
arch/m68k/mm/init.c | 7 ++++++-
arch/m68k/mm/mcfmmu.c | 2 +-
arch/m68k/mm/motorola.c | 2 +-
arch/m68k/mm/sun3mmu.c | 2 +-
4 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/arch/m68k/mm/init.c b/arch/m68k/mm/init.c
index 488411af1b3f..6b1d9d2434b5 100644
--- a/arch/m68k/mm/init.c
+++ b/arch/m68k/mm/init.c
@@ -40,6 +40,11 @@
void *empty_zero_page;
EXPORT_SYMBOL(empty_zero_page);

+void __init arch_zone_limits_init(unsigned long *max_zone_pfns)
+{
+ max_zone_pfns[ZONE_DMA] = PFN_DOWN(memblock_end_of_DRAM());
+}
+
#ifdef CONFIG_MMU

int m68k_virt_to_node_shift;
@@ -69,7 +74,7 @@ void __init paging_init(void)
high_memory = (void *) end_mem;

empty_zero_page = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
- max_zone_pfn[ZONE_DMA] = end_mem >> PAGE_SHIFT;
+ arch_zone_limits_init(max_zone_pfn);
free_area_init(max_zone_pfn);
}

diff --git a/arch/m68k/mm/mcfmmu.c b/arch/m68k/mm/mcfmmu.c
index 19a75029036c..24a6f7bbd1ce 100644
--- a/arch/m68k/mm/mcfmmu.c
+++ b/arch/m68k/mm/mcfmmu.c
@@ -73,7 +73,7 @@ void __init paging_init(void)
}

current->mm = NULL;
- max_zone_pfn[ZONE_DMA] = PFN_DOWN(_ramend);
+ arch_zone_limits_init(max_zone_pfn);
free_area_init(max_zone_pfn);
}

diff --git a/arch/m68k/mm/motorola.c b/arch/m68k/mm/motorola.c
index 62283bc2ed79..d6ccd23caf61 100644
--- a/arch/m68k/mm/motorola.c
+++ b/arch/m68k/mm/motorola.c
@@ -517,6 +517,6 @@ void __init paging_init(void)
if (node_present_pages(i))
node_set_state(i, N_NORMAL_MEMORY);

- max_zone_pfn[ZONE_DMA] = memblock_end_of_DRAM();
+ arch_zone_limits_init(max_zone_pfn);
free_area_init(max_zone_pfn);
}
diff --git a/arch/m68k/mm/sun3mmu.c b/arch/m68k/mm/sun3mmu.c
index 1ecf6bdd08bf..fdd69cc4240c 100644
--- a/arch/m68k/mm/sun3mmu.c
+++ b/arch/m68k/mm/sun3mmu.c
@@ -82,7 +82,7 @@ void __init paging_init(void)
current->mm = NULL;

/* memory sizing is a hack stolen from motorola.c.. hope it works for us */
- max_zone_pfn[ZONE_DMA] = ((unsigned long)high_memory) >> PAGE_SHIFT;
+ arch_zone_limits_init(max_zone_pfn);

/* I really wish I knew why the following change made things better... -- Sam */
free_area_init(max_zone_pfn);