[PATCH 04/28] arm64: introduce arch_zone_limits_init()

Mike Rapoport
2025-12-28T12:41:19Z

While on it rename zone_sizes_init() to dma_limits_init() to better
reflect what that function does.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
---
arch/arm64/mm/init.c | 22 +++++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 524d34a0e921..06815d34cc11 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -118,7 +118,21 @@ static phys_addr_t __init max_zone_phys(phys_addr_t zone_limit)
return min(zone_limit, memblock_end_of_DRAM() - 1) + 1;
}

-static void __init zone_sizes_init(void)
+void __init arch_zone_limits_init(unsigned long *max_zone_pfns)
+{
+ phys_addr_t __maybe_unused dma32_phys_limit =
+ max_zone_phys(DMA_BIT_MASK(32));
+
+#ifdef CONFIG_ZONE_DMA
+ max_zone_pfns[ZONE_DMA] = PFN_DOWN(max_zone_phys(zone_dma_limit));
+#endif
+#ifdef CONFIG_ZONE_DMA32
+ max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
+#endif
+ max_zone_pfns[ZONE_NORMAL] = max_pfn;
+}
+
+static void __init dma_limits_init(void)
{
unsigned long max_zone_pfns[MAX_NR_ZONES] = {0};
phys_addr_t __maybe_unused acpi_zone_dma_limit;
@@ -139,17 +153,15 @@ static void __init zone_sizes_init(void)
if (memblock_start_of_DRAM() < U32_MAX)
zone_dma_limit = min(zone_dma_limit, U32_MAX);
arm64_dma_phys_limit = max_zone_phys(zone_dma_limit);
- max_zone_pfns[ZONE_DMA] = PFN_DOWN(arm64_dma_phys_limit);
#endif
#ifdef CONFIG_ZONE_DMA32
- max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
if (!arm64_dma_phys_limit)
arm64_dma_phys_limit = dma32_phys_limit;
#endif
if (!arm64_dma_phys_limit)
arm64_dma_phys_limit = PHYS_MASK + 1;
- max_zone_pfns[ZONE_NORMAL] = max_pfn;

+ arch_zone_limits_init(max_zone_pfns);
free_area_init(max_zone_pfns);
}

@@ -319,7 +331,7 @@ void __init bootmem_init(void)
* done after the fixed reservations
*/
sparse_init();
- zone_sizes_init();
+ dma_limits_init();

/*
* Reserve the CMA area after arm64_dma_phys_limit was initialised.
--
2.51.0