2020-12-30 10:19:44

by chenzhou

Subject: [PATCH v2 0/3] arm64: mm: reserve CMA and crashkernel in ZONE_DMA if enabled

Currently, CMA and crashkernel are reserved in ZONE_DMA32, which
is OK for majority of devices. But the ones that need them in ZONE_DMA
need to configure it explicitly.

Since patchset "arm64: Default to 32-bit wide ZONE_DMA", ZONE_DMA's
size is fine-tuned. So we could directly reserve CMA and crashkernel
in ZONE_DMA if CONFIG_ZONE_DMA is enabled, otherwise, reserving in
ZONE_DMA32.

Patch 1 updates the comments about the ZONE_DMA.
Patch 2 move dma_contiguous_reserve() to bootmem_init()
Patch 3 reserve CMA and crashkernel in ZONE_DMA if enabled

Changes since v1:
- Add Reviewed-by for patch 1 from Nicolas.
- Suggested by Nicolas, also reserve CMA in ZONE_DMA if enabled.

Chen Zhou (3):
arm64: mm: update the comments about ZONE_DMA
arm64: mm: move dma_contiguous_reserve() to bootmem_init()
arm64: mm: reserve CMA and crashkernel in ZONE_DMA if enabled

arch/arm64/mm/init.c | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)

--
2.20.1

2020-12-30 10:19:54

by chenzhou

Subject: [PATCH v2 2/3] arm64: mm: move dma_contiguous_reserve() to bootmem_init()

Like crashkernel, CMA might also reserve memory located in ZONE_DMA,
so move dma_contiguous_reserve() to bootmem_init() to make sure that
arm64_dma_phys_limit is populated.

Just place dma_contiguous_reserve() after reserve_crashkernel() as
before.

Signed-off-by: Chen Zhou <[email protected]>
Suggested-by: Nicolas Saenz Julienne <[email protected]>
---
arch/arm64/mm/init.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 7b9809e39927..64a0e8f551d6 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -403,8 +403,6 @@ void __init arm64_memblock_init(void)
reserve_elfcorehdr();

high_memory = __va(memblock_end_of_DRAM() - 1) + 1;
-
- dma_contiguous_reserve(arm64_dma32_phys_limit);
}

void __init bootmem_init(void)
@@ -445,6 +443,8 @@ void __init bootmem_init(void)
*/
reserve_crashkernel();

+ dma_contiguous_reserve(arm64_dma32_phys_limit);
+
memblock_dump_all();
}

--
2.20.1

2020-12-30 10:22:25

by chenzhou

Subject: [PATCH v2 3/3] arm64: mm: reserve CMA and crashkernel in ZONE_DMA if enabled

Currently, CMA and crashkernel are reserved in ZONE_DMA32, which
is OK for majority of devices. But the ones that need them in ZONE_DMA
need to configure it explicitly.

Since patchset "arm64: Default to 32-bit wide ZONE_DMA", ZONE_DMA's
size is fine-tuned. So we could directly reserve CMA and crashkernel
in ZONE_DMA if CONFIG_ZONE_DMA is enabled, otherwise, reserving in
ZONE_DMA32.

Signed-off-by: Chen Zhou <[email protected]>
Suggested-by: Nicolas Saenz Julienne <[email protected]>
---
arch/arm64/mm/init.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 64a0e8f551d6..26de149b21c7 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -85,7 +85,8 @@ static void __init reserve_crashkernel(void)

if (crash_base == 0) {
/* Current arm64 boot protocol requires 2MB alignment */
- crash_base = memblock_find_in_range(0, arm64_dma32_phys_limit,
+ crash_base = memblock_find_in_range(0,
+ arm64_dma_phys_limit ? : arm64_dma32_phys_limit,
crash_size, SZ_2M);
if (crash_base == 0) {
pr_warn("cannot allocate crashkernel (size:0x%llx)\n",
@@ -443,7 +444,7 @@ void __init bootmem_init(void)
*/
reserve_crashkernel();

- dma_contiguous_reserve(arm64_dma32_phys_limit);
+ dma_contiguous_reserve(arm64_dma_phys_limit ? : arm64_dma32_phys_limit);

memblock_dump_all();
}
--
2.20.1