From 5ec9c4ff0430e33b602cc0ff8ab9dec8ef548d28 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 16 Jan 2018 09:37:50 +0100 Subject: 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 Signed-off-by: Christoph Hellwig Signed-off-by: Palmer Dabbelt --- arch/riscv/Kconfig | 5 +++++ arch/riscv/kernel/setup.c | 9 +++++++++ arch/riscv/mm/init.c | 10 ++++++---- 3 files changed, 20 insertions(+), 4 deletions(-) (limited to 'arch') 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 #include #include +#include #include #include @@ -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) -- cgit v1.2.3-58-ga151