arm64: Replace ZONE_DMA32 with ZONE_DMA

On arm64 we do not have two DMA zones, so it does not make sense to
implement ZONE_DMA32. This patch changes ZONE_DMA32 with ZONE_DMA, the
latter covering 32-bit dma address space to honour GFP_DMA allocations.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 0cb33a2..33e8f84 100644 (file)
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -86,7 +86,7 @@ config GENERIC_CSUM
 config GENERIC_CALIBRATE_DELAY
        def_bool y
 
-config ZONE_DMA32
+config ZONE_DMA
        def_bool y
 
 config ARCH_DMA_ADDR_T_64BIT

diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 985fc07..26b2512 100644 (file)
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -39,9 +39,9 @@ static void *__dma_alloc_coherent(struct device *dev, size_t size,
                return NULL;
        }
 
-       if (IS_ENABLED(CONFIG_ZONE_DMA32) &&
+       if (IS_ENABLED(CONFIG_ZONE_DMA) &&
            dev->coherent_dma_mask <= DMA_BIT_MASK(32))
-               flags |= GFP_DMA32;
+               flags |= GFP_DMA;
        if (IS_ENABLED(CONFIG_DMA_CMA)) {
                struct page *page;
 

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index d0b4c2e..a61a4d5 100644 (file)
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -30,6 +30,7 @@
 #include <linux/memblock.h>
 #include <linux/sort.h>
 #include <linux/of_fdt.h>
+#include <linux/dma-mapping.h>
 #include <linux/dma-contiguous.h>
 
 #include <asm/sections.h>
@@ -59,22 +60,22 @@ static int __init early_initrd(char *p)
 early_param("initrd", early_initrd);
 #endif
 
-#define MAX_DMA32_PFN ((4UL * 1024 * 1024 * 1024) >> PAGE_SHIFT)
-
 static void __init zone_sizes_init(unsigned long min, unsigned long max)
 {
        struct memblock_region *reg;
        unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
-       unsigned long max_dma32 = min;
+       unsigned long max_dma = min;
 
        memset(zone_size, 0, sizeof(zone_size));
 
-#ifdef CONFIG_ZONE_DMA32
        /* 4GB maximum for 32-bit only capable devices */
-       max_dma32 = max(min, min(max, MAX_DMA32_PFN));
-       zone_size[ZONE_DMA32] = max_dma32 - min;
-#endif
-       zone_size[ZONE_NORMAL] = max - max_dma32;
+       if (IS_ENABLED(CONFIG_ZONE_DMA)) {
+               unsigned long max_dma_phys =
+                       (unsigned long)dma_to_phys(NULL, DMA_BIT_MASK(32) + 1);
+               max_dma = max(min, min(max, max_dma_phys >> PAGE_SHIFT));
+               zone_size[ZONE_DMA] = max_dma - min;
+       }
+       zone_size[ZONE_NORMAL] = max - max_dma;
 
        memcpy(zhole_size, zone_size, sizeof(zhole_size));
 
@@ -84,15 +85,15 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)
 
                if (start >= max)
                        continue;
-#ifdef CONFIG_ZONE_DMA32
-               if (start < max_dma32) {
-                       unsigned long dma_end = min(end, max_dma32);
-                       zhole_size[ZONE_DMA32] -= dma_end - start;
+
+               if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) {
+                       unsigned long dma_end = min(end, max_dma);
+                       zhole_size[ZONE_DMA] -= dma_end - start;
                }
-#endif
-               if (end > max_dma32) {
+
+               if (end > max_dma) {
                        unsigned long normal_end = min(end, max);
-                       unsigned long normal_start = max(start, max_dma32);
+                       unsigned long normal_start = max(start, max_dma);
                        zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
                }
        }