External/cloud-hypervisor
1
0
Fork 0
mirror of https://github.com/cloud-hypervisor/cloud-hypervisor.git synced 2025-02-21 19:02:30 +00:00
Code Issues Packages Projects Releases Wiki Activity

aarch64: Add optional cpu-map node in device tree

Browse Source 
The Arm CPU topology is defined within the `cpu-map` node, which is
a direct child of the cpus node and provides a container where the
actual topology nodes are listed.

This commit adds an optional cpu-map node in device tree, based on
the Cloud Hypervisor command line vCPU topology information.

Signed-off-by: Henry Wang <Henry.Wang@arm.com>
This commit is contained in:
Henry Wang 2021-07-29 05:26:11 -04:00 committed by Michael
parent 7fb980f17b
commit 447c986916
1 changed files with 73 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

73
arch/src/aarch64/fdt.rs
View File

@ -34,6 +34,9 @@ const MSI_PHANDLE: u32 = 2;
const CLOCK_PHANDLE: u32 = 3;
// This is a value for uniquely identifying the FDT node containing the gpio controller.
const GPIO_PHANDLE: u32 = 4;
// This is a value for uniquely identifying the FDT node containing the first vCPU.
// The last number of vCPU phandle depends on the number of vCPUs.
const FIRST_VCPU_PHANDLE: u32 = 5;
// Read the documentation specified when appending the root node to the FDT.
const ADDRESS_CELLS: u32 = 0x2;
@ -137,7 +140,11 @@ fn create_cpu_nodes(
let cpus_node = fdt.begin_node("cpus")?;
fdt.property_u32("#address-cells", 0x1)?;
fdt.property_u32("#size-cells", 0x0)?;
let num_cpus = vcpu_mpidr.len();
let threads_per_core = vcpu_topology.unwrap_or_default().0 as u8;
let cores_per_package = vcpu_topology.unwrap_or_default().1 as u8;
let packages = vcpu_topology.unwrap_or_default().2 as u8;
for (cpu_id, mpidr) in vcpu_mpidr.iter().enumerate().take(num_cpus) {
let cpu_name = format!("cpu@{:x}", cpu_id);
@ -151,9 +158,75 @@ fn create_cpu_nodes(
// Set the field to first 24 bits of the MPIDR - Multiprocessor Affinity Register.
// See http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0488c/BABHBJCI.html.
fdt.property_u32("reg", (mpidr & 0x7FFFFF) as u32)?;
fdt.property_u32("phandle", cpu_id as u32 + FIRST_VCPU_PHANDLE)?;
fdt.end_node(cpu_node)?;
}
// If there is a valid cpu topology config, create the cpu-map node.
if (threads_per_core > 0)
&& (cores_per_package > 0)
&& (packages > 0)
&& (num_cpus as u8 == threads_per_core * cores_per_package * packages)
{
let cpu_map_node = fdt.begin_node("cpu-map")?;
// Create mappings between CPU index and cluster,core, and thread.
let mut cluster_core_thread_to_cpuidx = HashMap::new();
for cpu_idx in 0..num_cpus as u8 {
if threads_per_core > 1 {
cluster_core_thread_to_cpuidx.insert(
(
cpu_idx / (cores_per_package * threads_per_core),
(cpu_idx / threads_per_core) % cores_per_package,
cpu_idx % threads_per_core,
),
cpu_idx,
);
} else {
cluster_core_thread_to_cpuidx.insert(
(cpu_idx / cores_per_package, cpu_idx % cores_per_package, 0),
cpu_idx,
);
}
}
// Create device tree nodes with regard of above mapping.
for cluster_idx in 0..packages {
let cluster_name = format!("cluster{:x}", cluster_idx);
let cluster_node = fdt.begin_node(&cluster_name)?;
for core_idx in 0..cores_per_package {
let core_name = format!("core{:x}", core_idx);
let core_node = fdt.begin_node(&core_name)?;
if threads_per_core > 1 {
for thread_idx in 0..threads_per_core {
let thread_name = format!("thread{:x}", thread_idx);
let thread_node = fdt.begin_node(&thread_name)?;
let cpu_idx = cluster_core_thread_to_cpuidx
.get(&(cluster_idx, core_idx, thread_idx))
.unwrap();
fdt.property_u32("cpu", *cpu_idx as u32 + FIRST_VCPU_PHANDLE)?;
fdt.end_node(thread_node)?;
}
} else {
let cpu_idx = cluster_core_thread_to_cpuidx
.get(&(cluster_idx, core_idx, 0))
.unwrap();
fdt.property_u32("cpu", *cpu_idx as u32 + FIRST_VCPU_PHANDLE)?;
}
fdt.end_node(core_node)?;
}
fdt.end_node(cluster_node)?;
}
fdt.end_node(cpu_map_node)?;
} else {
debug!("Boot using device tree, CPU topology is not (correctly) specified");
}
fdt.end_node(cpus_node)?;
Ok(())
}