diff options
| author | Catalin Marinas <catalin.marinas@arm.com> | 2024-08-11 10:09:35 +0300 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2024-08-22 06:18:00 +0200 |
| commit | ba0fb44aed47693cc2482427f63ba6cd19051327 (patch) | |
| tree | 621c630705defd780fbeac9b9b103f3c80264c23 /arch/arm64/mm/init.c | |
| parent | fa3c109a6d302b56437a6412c5f3044c3e12de03 (diff) | |
dma-mapping: replace zone_dma_bits by zone_dma_limit
The hardware DMA limit might not be power of 2. When RAM range starts
above 0, say 4GB, DMA limit of 30 bits should end at 5GB. A single high
bit can not encode this limit.
Use a plain address for the DMA zone limit instead.
Since the DMA zone can now potentially span beyond 4GB physical limit of
DMA32, make sure to use DMA zone for GFP_DMA32 allocations in that case.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Co-developed-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Petr Tesarik <ptesarik@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'arch/arm64/mm/init.c')
| -rw-r--r-- | arch/arm64/mm/init.c | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 9b5ab6818f7f..c45e2152ca9e 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -115,35 +115,35 @@ static void __init arch_reserve_crashkernel(void) } /* - * Return the maximum physical address for a zone accessible by the given bits - * limit. If DRAM starts above 32-bit, expand the zone to the maximum + * Return the maximum physical address for a zone given its limit. + * If DRAM starts above 32-bit, expand the zone to the maximum * available memory, otherwise cap it at 32-bit. */ -static phys_addr_t __init max_zone_phys(unsigned int zone_bits) +static phys_addr_t __init max_zone_phys(phys_addr_t zone_limit) { - phys_addr_t zone_mask = DMA_BIT_MASK(zone_bits); phys_addr_t phys_start = memblock_start_of_DRAM(); if (phys_start > U32_MAX) - zone_mask = PHYS_ADDR_MAX; - else if (phys_start > zone_mask) - zone_mask = U32_MAX; + zone_limit = PHYS_ADDR_MAX; + else if (phys_start > zone_limit) + zone_limit = U32_MAX; - return min(zone_mask, memblock_end_of_DRAM() - 1) + 1; + return min(zone_limit, memblock_end_of_DRAM() - 1) + 1; } static void __init zone_sizes_init(void) { unsigned long max_zone_pfns[MAX_NR_ZONES] = {0}; - unsigned int __maybe_unused acpi_zone_dma_bits; - unsigned int __maybe_unused dt_zone_dma_bits; - phys_addr_t __maybe_unused dma32_phys_limit = max_zone_phys(32); + phys_addr_t __maybe_unused acpi_zone_dma_limit; + phys_addr_t __maybe_unused dt_zone_dma_limit; + phys_addr_t __maybe_unused dma32_phys_limit = + max_zone_phys(DMA_BIT_MASK(32)); #ifdef CONFIG_ZONE_DMA - acpi_zone_dma_bits = fls64(acpi_iort_dma_get_max_cpu_address()); - dt_zone_dma_bits = fls64(of_dma_get_max_cpu_address(NULL)); - zone_dma_bits = min3(32U, dt_zone_dma_bits, acpi_zone_dma_bits); - arm64_dma_phys_limit = max_zone_phys(zone_dma_bits); + acpi_zone_dma_limit = acpi_iort_dma_get_max_cpu_address(); + dt_zone_dma_limit = of_dma_get_max_cpu_address(NULL); + zone_dma_limit = min(dt_zone_dma_limit, acpi_zone_dma_limit); + 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 |