From: Kefeng Wang <wangkefeng.wang@huawei.com>
Date: Sat, 31 Oct 2020 06:01:12 +0000 (+0800)
Subject: riscv: Enable CMA support
X-Git-Tag: v5.10.155~46
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d7716240bca508fb9e74d00d96304bc30acc3d6c;p=thirdparty%2Fkernel%2Fstable.git

riscv: Enable CMA support

[ Upstream commit da815582cf4594e96defa1cddb72cd00b1e7aac5 ]

riscv has selected HAVE_DMA_CONTIGUOUS, but doesn't call
dma_contiguous_reserve().  This calls dma_contiguous_reserve(), which
enables CMA.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Stable-dep-of: 50e63dd8ed92 ("riscv: fix reserved memory setup")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index e8921e78a2926..56314e82f0512 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -13,6 +13,7 @@
 #include <linux/of_fdt.h>
 #include <linux/libfdt.h>
 #include <linux/set_memory.h>
+#include <linux/dma-map-ops.h>
 
 #include <asm/fixmap.h>
 #include <asm/tlbflush.h>
@@ -41,13 +42,14 @@ struct pt_alloc_ops {
 #endif
 };
 
+static phys_addr_t dma32_phys_limit __ro_after_init;
+
 static void __init zone_sizes_init(void)
 {
 	unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
 
 #ifdef CONFIG_ZONE_DMA32
-	max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G,
-			(unsigned long) PFN_PHYS(max_low_pfn)));
+	max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
 #endif
 	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 
@@ -193,6 +195,7 @@ void __init setup_bootmem(void)
 
 	max_pfn = PFN_DOWN(dram_end);
 	max_low_pfn = max_pfn;
+	dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
 	set_max_mapnr(max_low_pfn);
 
 #ifdef CONFIG_BLK_DEV_INITRD
@@ -206,6 +209,7 @@ void __init setup_bootmem(void)
 	memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
 
 	early_init_fdt_scan_reserved_mem();
+	dma_contiguous_reserve(dma32_phys_limit);
 	memblock_allow_resize();
 	memblock_dump_all();
 }