diff options
| author | Christoph Hellwig <hch@lst.de> | 2018-01-16 09:37:50 +0100 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@dabbelt.com> | 2018-01-31 04:14:27 +0100 |
| commit | 5ec9c4ff0430e33b602cc0ff8ab9dec8ef548d28 (patch) | |
| tree | 3fb2ff5397466ecc5516d7e8d56e71e17e15ca41 /arch/riscv | |
| parent | RISC-V: Limit the scope of TLB shootdowns (diff) | |
| download | linux-5ec9c4ff0430e33b602cc0ff8ab9dec8ef548d28.tar.xz linux-5ec9c4ff0430e33b602cc0ff8ab9dec8ef548d28.zip | |
riscv: add ZONE_DMA32
This patch allows devices that require memory that can be addressed
using 32-bit addresses to work easily on RISC-V systems. The newly
improved dma-direct ops will tap into this pool automatically for
32-bit addressing.
Based on an earlier patch from Wesley W. Terpstra.
CC: Wesley W. Terpstra <terpstra@sifive.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Diffstat (limited to 'arch/riscv')
| -rw-r--r-- | arch/riscv/Kconfig | 5 | ||||
| -rw-r--r-- | arch/riscv/kernel/setup.c | 9 | ||||
| -rw-r--r-- | arch/riscv/mm/init.c | 10 |
3 files changed, 20 insertions, 4 deletions
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 504ba386b22e..0e66993f44cc 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -22,6 +22,7 @@ config RISCV select GENERIC_ATOMIC64 if !64BIT || !RISCV_ISA_A select ARCH_WANT_OPTIONAL_GPIOLIB select HAVE_MEMBLOCK + select HAVE_MEMBLOCK_NODE_MAP select HAVE_DMA_API_DEBUG select HAVE_DMA_CONTIGUOUS select HAVE_GENERIC_DMA_COHERENT @@ -43,6 +44,10 @@ config MMU config ARCH_PHYS_ADDR_T_64BIT def_bool y +config ZONE_DMA32 + bool + default y + config ARCH_DMA_ADDR_T_64BIT def_bool y diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index c6d095ff5ab8..09f7064e898c 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -181,6 +181,15 @@ static void __init setup_bootmem(void) early_init_fdt_scan_reserved_mem(); memblock_allow_resize(); memblock_dump_all(); + + for_each_memblock(memory, reg) { + unsigned long start_pfn = memblock_region_memory_base_pfn(reg); + unsigned long end_pfn = memblock_region_memory_end_pfn(reg); + + memblock_set_node(PFN_PHYS(start_pfn), + PFN_PHYS(end_pfn - start_pfn), + &memblock.memory, 0); + } } void __init setup_arch(char **cmdline_p) diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 9f4bee5e51fd..a6c0e8e7d888 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -17,6 +17,7 @@ #include <linux/initrd.h> #include <linux/memblock.h> #include <linux/swap.h> +#include <linux/sizes.h> #include <asm/tlbflush.h> #include <asm/sections.h> @@ -25,11 +26,12 @@ static void __init zone_sizes_init(void) { - unsigned long zones_size[MAX_NR_ZONES]; + unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, }; - memset(zones_size, 0, sizeof(zones_size)); - zones_size[ZONE_NORMAL] = max_mapnr; - free_area_init_node(0, zones_size, pfn_base, NULL); + max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G, max_low_pfn)); + max_zone_pfns[ZONE_NORMAL] = max_low_pfn; + + free_area_init_nodes(max_zone_pfns); } void setup_zero_page(void) |