From eef015c8aa74451f848307fe5f65485070533bbb Mon Sep 17 00:00:00 2001 From: Chris Metcalf Date: Wed, 9 May 2012 12:26:30 -0400 Subject: arch/tile: enable ZONE_DMA for tilegx This is required for PCI root complex legacy support and USB OHCI root complex support. With this change tilegx now supports allocating memory whose PA fits in 32 bits. Signed-off-by: Chris Metcalf --- arch/tile/kernel/pci-dma.c | 15 +++++++++------ arch/tile/kernel/setup.c | 12 +++++++++++- 2 files changed, 20 insertions(+), 7 deletions(-) (limited to 'arch/tile/kernel') diff --git a/arch/tile/kernel/pci-dma.c b/arch/tile/kernel/pci-dma.c index 9814d70..edd856a 100644 --- a/arch/tile/kernel/pci-dma.c +++ b/arch/tile/kernel/pci-dma.c @@ -45,14 +45,17 @@ void *dma_alloc_coherent(struct device *dev, gfp |= __GFP_ZERO; /* - * By forcing NUMA node 0 for 32-bit masks we ensure that the - * high 32 bits of the resulting PA will be zero. If the mask - * size is, e.g., 24, we may still not be able to guarantee a - * suitable memory address, in which case we will return NULL. - * But such devices are uncommon. + * If the mask specifies that the memory be in the first 4 GB, then + * we force the allocation to come from the DMA zone. We also + * force the node to 0 since that's the only node where the DMA + * zone isn't empty. If the mask size is smaller than 32 bits, we + * may still not be able to guarantee a suitable memory address, in + * which case we will return NULL. But such devices are uncommon. */ - if (dma_mask <= DMA_BIT_MASK(32)) + if (dma_mask <= DMA_BIT_MASK(32)) { + gfp |= GFP_DMA; node = 0; + } pg = homecache_alloc_pages_node(node, gfp, order, PAGE_HOME_DMA); if (pg == NULL) diff --git a/arch/tile/kernel/setup.c b/arch/tile/kernel/setup.c index 6d179df..fdde3b6 100644 --- a/arch/tile/kernel/setup.c +++ b/arch/tile/kernel/setup.c @@ -658,6 +658,8 @@ static void __init zone_sizes_init(void) unsigned long zones_size[MAX_NR_ZONES] = { 0 }; int size = percpu_size(); int num_cpus = smp_height * smp_width; + const unsigned long dma_end = (1UL << (32 - PAGE_SHIFT)); + int i; for (i = 0; i < num_cpus; ++i) @@ -729,6 +731,14 @@ static void __init zone_sizes_init(void) zones_size[ZONE_NORMAL] = end - start; #endif + if (start < dma_end) { + zones_size[ZONE_DMA] = min(zones_size[ZONE_NORMAL], + dma_end - start); + zones_size[ZONE_NORMAL] -= zones_size[ZONE_DMA]; + } else { + zones_size[ZONE_DMA] = 0; + } + /* Take zone metadata from controller 0 if we're isolnode. */ if (node_isset(i, isolnodes)) NODE_DATA(i)->bdata = &bootmem_node_data[0]; @@ -738,7 +748,7 @@ static void __init zone_sizes_init(void) PFN_UP(node_percpu[i])); /* Track the type of memory on each node */ - if (zones_size[ZONE_NORMAL]) + if (zones_size[ZONE_NORMAL] || zones_size[ZONE_DMA]) node_set_state(i, N_NORMAL_MEMORY); #ifdef CONFIG_HIGHMEM if (end != start) -- cgit v1.1