summaryrefslogtreecommitdiffstats
path: root/arch
diff options
context:
space:
mode:
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/kernel/e820_64.c19
-rw-r--r--arch/x86_64/Kconfig19
2 files changed, 34 insertions, 4 deletions
diff --git a/arch/x86/kernel/e820_64.c b/arch/x86/kernel/e820_64.c
index 57616865d8a0..1ca228b06a20 100644
--- a/arch/x86/kernel/e820_64.c
+++ b/arch/x86/kernel/e820_64.c
@@ -729,3 +729,22 @@ __init void e820_setup_gap(void)
printk(KERN_INFO "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n",
pci_mem_start, gapstart, gapsize);
}
+
+int __init arch_get_ram_range(int slot, u64 *addr, u64 *size)
+{
+ int i;
+
+ if (slot < 0 || slot >= e820.nr_map)
+ return -1;
+ for (i = slot; i < e820.nr_map; i++) {
+ if (e820.map[i].type != E820_RAM)
+ continue;
+ break;
+ }
+ if (i == e820.nr_map || e820.map[i].addr > (max_pfn << PAGE_SHIFT))
+ return -1;
+ *addr = e820.map[i].addr;
+ *size = min_t(u64, e820.map[i].size + e820.map[i].addr,
+ max_pfn << PAGE_SHIFT) - *addr;
+ return i + 1;
+}
diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig
index 5c9aaed589a5..5cf941774347 100644
--- a/arch/x86_64/Kconfig
+++ b/arch/x86_64/Kconfig
@@ -755,11 +755,22 @@ config DMAR
depends on PCI_MSI && ACPI && EXPERIMENTAL
default y
help
- DMA remapping(DMAR) devices support enables independent address
- translations for Direct Memory Access(DMA) from Devices.
+ DMA remapping (DMAR) devices support enables independent address
+ translations for Direct Memory Access (DMA) from devices.
These DMA remapping devices are reported via ACPI tables
- and includes pci device scope covered by these DMA
- remapping device.
+ and include PCI device scope covered by these DMA
+ remapping devices.
+
+config DMAR_GFX_WA
+ bool "Support for Graphics workaround"
+ depends on DMAR
+ default y
+ help
+ Current Graphics drivers tend to use physical address
+ for DMA and avoid using DMA APIs. Setting this config
+ option permits the IOMMU driver to set a unity map for
+ all the OS-visible memory. Hence the driver can continue
+ to use physical addresses for DMA.
source "drivers/pci/pcie/Kconfig"
OpenPOWER on IntegriCloud