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authorLinus Torvalds <torvalds@linux-foundation.org>2016-05-16 17:17:24 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-05-16 17:17:24 -0700
commitbe092017b6ffbd013f481f915632db6aa9fc3ca3 (patch)
tree56f37b2b232ef41c0202c4f57d8e83e93d9168f4 /Documentation
parentfb6363e9f4eeb37323feb8253b93854195942b8b (diff)
parente6d9a52543338603e25e71e0e4942f05dae0dd8a (diff)
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon: - virt_to_page/page_address optimisations - support for NUMA systems described using device-tree - support for hibernate/suspend-to-disk - proper support for maxcpus= command line parameter - detection and graceful handling of AArch64-only CPUs - miscellaneous cleanups and non-critical fixes * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits) arm64: do not enforce strict 16 byte alignment to stack pointer arm64: kernel: Fix incorrect brk randomization arm64: cpuinfo: Missing NULL terminator in compat_hwcap_str arm64: secondary_start_kernel: Remove unnecessary barrier arm64: Ensure pmd_present() returns false after pmd_mknotpresent() arm64: Replace hard-coded values in the pmd/pud_bad() macros arm64: Implement pmdp_set_access_flags() for hardware AF/DBM arm64: Fix typo in the pmdp_huge_get_and_clear() definition arm64: mm: remove unnecessary EXPORT_SYMBOL_GPL arm64: always use STRICT_MM_TYPECHECKS arm64: kvm: Fix kvm teardown for systems using the extended idmap arm64: kaslr: increase randomization granularity arm64: kconfig: drop CONFIG_RTC_LIB dependency arm64: make ARCH_SUPPORTS_DEBUG_PAGEALLOC depend on !HIBERNATION arm64: hibernate: Refuse to hibernate if the boot cpu is offline arm64: kernel: Add support for hibernate/suspend-to-disk PM / Hibernate: Call flush_icache_range() on pages restored in-place arm64: Add new asm macro copy_page arm64: Promote KERNEL_START/KERNEL_END definitions to a header file arm64: kernel: Include _AC definition in page.h ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/arm64/booting.txt4
-rw-r--r--Documentation/devicetree/bindings/numa.txt275
-rw-r--r--Documentation/kernel-parameters.txt6
3 files changed, 283 insertions, 2 deletions
diff --git a/Documentation/arm64/booting.txt b/Documentation/arm64/booting.txt
index 56d6d8b796db..8d0df62c3fe0 100644
--- a/Documentation/arm64/booting.txt
+++ b/Documentation/arm64/booting.txt
@@ -132,6 +132,10 @@ NOTE: versions prior to v4.6 cannot make use of memory below the
physical offset of the Image so it is recommended that the Image be
placed as close as possible to the start of system RAM.
+If an initrd/initramfs is passed to the kernel at boot, it must reside
+entirely within a 1 GB aligned physical memory window of up to 32 GB in
+size that fully covers the kernel Image as well.
+
Any memory described to the kernel (even that below the start of the
image) which is not marked as reserved from the kernel (e.g., with a
memreserve region in the device tree) will be considered as available to
diff --git a/Documentation/devicetree/bindings/numa.txt b/Documentation/devicetree/bindings/numa.txt
new file mode 100644
index 000000000000..21b35053ca5a
--- /dev/null
+++ b/Documentation/devicetree/bindings/numa.txt
@@ -0,0 +1,275 @@
+==============================================================================
+NUMA binding description.
+==============================================================================
+
+==============================================================================
+1 - Introduction
+==============================================================================
+
+Systems employing a Non Uniform Memory Access (NUMA) architecture contain
+collections of hardware resources including processors, memory, and I/O buses,
+that comprise what is commonly known as a NUMA node.
+Processor accesses to memory within the local NUMA node is generally faster
+than processor accesses to memory outside of the local NUMA node.
+DT defines interfaces that allow the platform to convey NUMA node
+topology information to OS.
+
+==============================================================================
+2 - numa-node-id
+==============================================================================
+
+For the purpose of identification, each NUMA node is associated with a unique
+token known as a node id. For the purpose of this binding
+a node id is a 32-bit integer.
+
+A device node is associated with a NUMA node by the presence of a
+numa-node-id property which contains the node id of the device.
+
+Example:
+ /* numa node 0 */
+ numa-node-id = <0>;
+
+ /* numa node 1 */
+ numa-node-id = <1>;
+
+==============================================================================
+3 - distance-map
+==============================================================================
+
+The optional device tree node distance-map describes the relative
+distance (memory latency) between all numa nodes.
+
+- compatible : Should at least contain "numa-distance-map-v1".
+
+- distance-matrix
+ This property defines a matrix to describe the relative distances
+ between all numa nodes.
+ It is represented as a list of node pairs and their relative distance.
+
+ Note:
+ 1. Each entry represents distance from first node to second node.
+ The distances are equal in either direction.
+ 2. The distance from a node to self (local distance) is represented
+ with value 10 and all internode distance should be represented with
+ a value greater than 10.
+ 3. distance-matrix should have entries in lexicographical ascending
+ order of nodes.
+ 4. There must be only one device node distance-map which must
+ reside in the root node.
+ 5. If the distance-map node is not present, a default
+ distance-matrix is used.
+
+Example:
+ 4 nodes connected in mesh/ring topology as below,
+
+ 0_______20______1
+ | |
+ | |
+ 20 20
+ | |
+ | |
+ |_______________|
+ 3 20 2
+
+ if relative distance for each hop is 20,
+ then internode distance would be,
+ 0 -> 1 = 20
+ 1 -> 2 = 20
+ 2 -> 3 = 20
+ 3 -> 0 = 20
+ 0 -> 2 = 40
+ 1 -> 3 = 40
+
+ and dt presentation for this distance matrix is,
+
+ distance-map {
+ compatible = "numa-distance-map-v1";
+ distance-matrix = <0 0 10>,
+ <0 1 20>,
+ <0 2 40>,
+ <0 3 20>,
+ <1 0 20>,
+ <1 1 10>,
+ <1 2 20>,
+ <1 3 40>,
+ <2 0 40>,
+ <2 1 20>,
+ <2 2 10>,
+ <2 3 20>,
+ <3 0 20>,
+ <3 1 40>,
+ <3 2 20>,
+ <3 3 10>;
+ };
+
+==============================================================================
+4 - Example dts
+==============================================================================
+
+Dual socket system consists of 2 boards connected through ccn bus and
+each board having one socket/soc of 8 cpus, memory and pci bus.
+
+ memory@c00000 {
+ device_type = "memory";
+ reg = <0x0 0xc00000 0x0 0x80000000>;
+ /* node 0 */
+ numa-node-id = <0>;
+ };
+
+ memory@10000000000 {
+ device_type = "memory";
+ reg = <0x100 0x0 0x0 0x80000000>;
+ /* node 1 */
+ numa-node-id = <1>;
+ };
+
+ cpus {
+ #address-cells = <2>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0x0>;
+ enable-method = "psci";
+ /* node 0 */
+ numa-node-id = <0>;
+ };
+ cpu@1 {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0x1>;
+ enable-method = "psci";
+ numa-node-id = <0>;
+ };
+ cpu@2 {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0x2>;
+ enable-method = "psci";
+ numa-node-id = <0>;
+ };
+ cpu@3 {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0x3>;
+ enable-method = "psci";
+ numa-node-id = <0>;
+ };
+ cpu@4 {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0x4>;
+ enable-method = "psci";
+ numa-node-id = <0>;
+ };
+ cpu@5 {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0x5>;
+ enable-method = "psci";
+ numa-node-id = <0>;
+ };
+ cpu@6 {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0x6>;
+ enable-method = "psci";
+ numa-node-id = <0>;
+ };
+ cpu@7 {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0x7>;
+ enable-method = "psci";
+ numa-node-id = <0>;
+ };
+ cpu@8 {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0x8>;
+ enable-method = "psci";
+ /* node 1 */
+ numa-node-id = <1>;
+ };
+ cpu@9 {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0x9>;
+ enable-method = "psci";
+ numa-node-id = <1>;
+ };
+ cpu@a {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0xa>;
+ enable-method = "psci";
+ numa-node-id = <1>;
+ };
+ cpu@b {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0xb>;
+ enable-method = "psci";
+ numa-node-id = <1>;
+ };
+ cpu@c {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0xc>;
+ enable-method = "psci";
+ numa-node-id = <1>;
+ };
+ cpu@d {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0xd>;
+ enable-method = "psci";
+ numa-node-id = <1>;
+ };
+ cpu@e {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0xe>;
+ enable-method = "psci";
+ numa-node-id = <1>;
+ };
+ cpu@f {
+ device_type = "cpu";
+ compatible = "arm,armv8";
+ reg = <0x0 0xf>;
+ enable-method = "psci";
+ numa-node-id = <1>;
+ };
+ };
+
+ pcie0: pcie0@848000000000 {
+ compatible = "arm,armv8";
+ device_type = "pci";
+ bus-range = <0 255>;
+ #size-cells = <2>;
+ #address-cells = <3>;
+ reg = <0x8480 0x00000000 0 0x10000000>; /* Configuration space */
+ ranges = <0x03000000 0x8010 0x00000000 0x8010 0x00000000 0x70 0x00000000>;
+ /* node 0 */
+ numa-node-id = <0>;
+ };
+
+ pcie1: pcie1@948000000000 {
+ compatible = "arm,armv8";
+ device_type = "pci";
+ bus-range = <0 255>;
+ #size-cells = <2>;
+ #address-cells = <3>;
+ reg = <0x9480 0x00000000 0 0x10000000>; /* Configuration space */
+ ranges = <0x03000000 0x9010 0x00000000 0x9010 0x00000000 0x70 0x00000000>;
+ /* node 1 */
+ numa-node-id = <1>;
+ };
+
+ distance-map {
+ compatible = "numa-distance-map-v1";
+ distance-matrix = <0 0 10>,
+ <0 1 20>,
+ <1 1 10>;
+ };
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 13f89d18bc25..09126c2307d2 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -168,16 +168,18 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
acpi= [HW,ACPI,X86,ARM64]
Advanced Configuration and Power Interface
- Format: { force | off | strict | noirq | rsdt |
+ Format: { force | on | off | strict | noirq | rsdt |
copy_dsdt }
force -- enable ACPI if default was off
+ on -- enable ACPI but allow fallback to DT [arm64]
off -- disable ACPI if default was on
noirq -- do not use ACPI for IRQ routing
strict -- Be less tolerant of platforms that are not
strictly ACPI specification compliant.
rsdt -- prefer RSDT over (default) XSDT
copy_dsdt -- copy DSDT to memory
- For ARM64, ONLY "acpi=off" or "acpi=force" are available
+ For ARM64, ONLY "acpi=off", "acpi=on" or "acpi=force"
+ are available
See also Documentation/power/runtime_pm.txt, pci=noacpi