diff --git a/src/plat/allwinnerA20/overlay-allwinnerA20.dts b/src/plat/allwinnerA20/overlay-allwinnerA20.dts
index a6a58e4d6f8c2bfe6691097ba5eff5d83b8272ce..0c08583fecf4851f4e310f4f93da2b92523d0594 100644
--- a/src/plat/allwinnerA20/overlay-allwinnerA20.dts
+++ b/src/plat/allwinnerA20/overlay-allwinnerA20.dts
@@ -12,6 +12,9 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial0";
+
seL4,kernel-devices =
"serial0",
&{/soc@1c00000/interrupt-controller@1c81000},
diff --git a/src/plat/am335x/overlay-am335x.dts b/src/plat/am335x/overlay-am335x.dts
index 8cd502addb7c5204851b3c68df7ab024ec13e5db..5427e988dd00f06bc4b5f2aedddc5c1254b238e8 100644
--- a/src/plat/am335x/overlay-am335x.dts
+++ b/src/plat/am335x/overlay-am335x.dts
@@ -12,6 +12,8 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial0";
seL4,kernel-devices =
"serial0",
&{/ocp/interrupt-controller@48200000},
diff --git a/src/plat/apq8064/overlay-apq8064.dts b/src/plat/apq8064/overlay-apq8064.dts
index 49b0d1088251ad9c6d9c8e96e8251d37cd4809f6..60f56fb9bb813fed7855b1765e8f3602bf7db5b6 100644
--- a/src/plat/apq8064/overlay-apq8064.dts
+++ b/src/plat/apq8064/overlay-apq8064.dts
@@ -12,6 +12,8 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial0";
seL4,kernel-devices =
"serial0",
&{/soc/interrupt-controller@2000000},
diff --git a/src/plat/bcm2837/overlay-rpi3.dts b/src/plat/bcm2837/overlay-rpi3.dts
index e3219d30250a68cae3ab99301afbd325c9df9737..5f783209a48afc47c2fe353cccc9423464270f9d 100644
--- a/src/plat/bcm2837/overlay-rpi3.dts
+++ b/src/plat/bcm2837/overlay-rpi3.dts
@@ -12,6 +12,9 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial1";
+
seL4,kernel-devices =
"serial1",
&{/soc/interrupt-controller@7e00b200},
diff --git a/src/plat/exynos4/overlay-exynos4.dts b/src/plat/exynos4/overlay-exynos4.dts
index ece5d960e42d80adc5966c195461aef542792ee5..02873cd908d89d2ce628ff17a94e400ff48b256f 100644
--- a/src/plat/exynos4/overlay-exynos4.dts
+++ b/src/plat/exynos4/overlay-exynos4.dts
@@ -12,6 +12,9 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial1";
+
seL4,kernel-devices =
"serial1",
&{/soc/interrupt-controller@10490000},
diff --git a/src/plat/exynos5/overlay-exynos5250.dts b/src/plat/exynos5/overlay-exynos5250.dts
index 510b269a3ce189185bd218d83173a80b2624ca34..009f629ef2b74b135b3e9cccc2e6f0a5c784a433 100644
--- a/src/plat/exynos5/overlay-exynos5250.dts
+++ b/src/plat/exynos5/overlay-exynos5250.dts
@@ -14,6 +14,8 @@
/* Pick serial console */
chosen {
stdout-path = "serial2:115200n8";
+ seL4,elfloader-devices =
+ "serial2";
seL4,kernel-devices =
"serial2",
&{/soc/interrupt-controller@10481000},
diff --git a/src/plat/exynos5/overlay-exynos5410.dts b/src/plat/exynos5/overlay-exynos5410.dts
index d673defd5a5c58bf24a10fb3f37a105593d169c3..6c75a42ecb51f11d272eabb752bda896571e07a2 100644
--- a/src/plat/exynos5/overlay-exynos5410.dts
+++ b/src/plat/exynos5/overlay-exynos5410.dts
@@ -14,6 +14,8 @@
/* pick the right boot CPU */
chosen {
seL4,boot-cpu = <&{/cpus/cpu@0}>;
+ seL4,elfloader-devices =
+ "serial2";
seL4,kernel-devices =
"serial2",
&{/soc/interrupt-controller@10481000},
diff --git a/src/plat/exynos5/overlay-exynos5422.dts b/src/plat/exynos5/overlay-exynos5422.dts
index 46999dee22e760fd3e7c2b76281488c95a8c2c81..04643b6c211ab6cc852563b7164247f576d1916c 100644
--- a/src/plat/exynos5/overlay-exynos5422.dts
+++ b/src/plat/exynos5/overlay-exynos5422.dts
@@ -20,6 +20,8 @@
*/
chosen {
seL4,boot-cpu = <&{/cpus/cpu@100}>;
+ seL4,elfloader-devices =
+ "serial2";
seL4,kernel-devices =
"serial2",
&{/soc/interrupt-controller@10481000},
diff --git a/src/plat/fvp/overlay-fvp.dts b/src/plat/fvp/overlay-fvp.dts
index 61fbc2619c3554f557a4b8ebcf7b734f06f0d9e3..e213b163ee8326023d7ea0b75276ff5ffbb37244 100644
--- a/src/plat/fvp/overlay-fvp.dts
+++ b/src/plat/fvp/overlay-fvp.dts
@@ -12,6 +12,10 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial0",
+ &{/psci};
+
seL4,kernel-devices =
"serial0",
&{/interrupt-controller@2f000000},
diff --git a/src/plat/hikey/overlay-hikey.dts b/src/plat/hikey/overlay-hikey.dts
index 89b41726e8217b61bb91e5d252f66a4d09c9b102..f764f10acfa3c987307c257b7e38bd560f2db99d 100644
--- a/src/plat/hikey/overlay-hikey.dts
+++ b/src/plat/hikey/overlay-hikey.dts
@@ -13,6 +13,11 @@
/ {
chosen {
stdout-path = "serial0:115200n8";
+
+ seL4,elfloader-devices =
+ "serial0",
+ &{/psci};
+
seL4,kernel-devices =
"serial0",
&{/interrupt-controller@f6801000},
diff --git a/src/plat/imx31/overlay-kzm.dts b/src/plat/imx31/overlay-kzm.dts
index 96d37bf7e4451a14223f4d3be04665bf67989975..a8b7ba7b261a533292d5d929b1f498548e81adf7 100644
--- a/src/plat/imx31/overlay-kzm.dts
+++ b/src/plat/imx31/overlay-kzm.dts
@@ -14,6 +14,8 @@
/* Pick serial console */
chosen {
stdout-path = "serial0";
+ seL4,elfloader-devices =
+ "serial0";
seL4,kernel-devices =
"serial0",
&{/interrupt-controller@68000000},
diff --git a/src/plat/imx6/overlay-sabre.dts b/src/plat/imx6/overlay-sabre.dts
index 5e4d63eead7949e3a810b16b6d61c01be0333103..f6e799b9c4b5c022fe360bc5c080c1f425f4702b 100644
--- a/src/plat/imx6/overlay-sabre.dts
+++ b/src/plat/imx6/overlay-sabre.dts
@@ -12,6 +12,10 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial1",
+ &{/soc/aips-bus@2000000/src@20d8000};
+
seL4,kernel-devices =
"serial1",
&{/soc/interrupt-controller@a01000},
diff --git a/src/plat/imx6/overlay-wandq.dts b/src/plat/imx6/overlay-wandq.dts
index 6952a92438b4f0ad6855893c8bf01fd3744be4df..ad74db66d061e1c15b31addb22d9d8b6e03f3cd3 100644
--- a/src/plat/imx6/overlay-wandq.dts
+++ b/src/plat/imx6/overlay-wandq.dts
@@ -12,6 +12,10 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial0",
+ &{/soc/aips-bus@2000000/src@20d8000};
+
seL4,kernel-devices =
"serial0",
&{/soc/interrupt-controller@a01000},
diff --git a/src/plat/imx7/overlay-imx7sabre.dts b/src/plat/imx7/overlay-imx7sabre.dts
index c910b0d0493514f4aac84c3036b33ce77e625685..19e33a2c52a9f0876be4f04a6d5a01701a905d11 100644
--- a/src/plat/imx7/overlay-imx7sabre.dts
+++ b/src/plat/imx7/overlay-imx7sabre.dts
@@ -12,6 +12,8 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial0";
seL4,kernel-devices =
"serial0",
&{/soc/interrupt-controller@31001000},
diff --git a/src/plat/imx8m-evk/overlay-imx8mm-evk.dts b/src/plat/imx8m-evk/overlay-imx8mm-evk.dts
index abc2596fa167885baf525937a75b79e15a87ce43..fe553eaf30e05c81da8dde7fb4500d9081564a4b 100644
--- a/src/plat/imx8m-evk/overlay-imx8mm-evk.dts
+++ b/src/plat/imx8m-evk/overlay-imx8mm-evk.dts
@@ -12,6 +12,10 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial1",
+ &{/psci};
+
seL4,kernel-devices =
"serial1",
&{/interrupt-controller@38800000},
diff --git a/src/plat/imx8m-evk/overlay-imx8mq-evk.dts b/src/plat/imx8m-evk/overlay-imx8mq-evk.dts
index 0ef1fe5ff27782441d7dc70d65dea48871ced38f..5bd284d4dafe201363776b022486ffc482f039ea 100644
--- a/src/plat/imx8m-evk/overlay-imx8mq-evk.dts
+++ b/src/plat/imx8m-evk/overlay-imx8mq-evk.dts
@@ -12,6 +12,10 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial0",
+ &{/psci};
+
seL4,kernel-devices =
"serial0",
&{/interrupt-controller@38800000},
diff --git a/src/plat/odroidc2/overlay-odroidc2.dts b/src/plat/odroidc2/overlay-odroidc2.dts
index d00b10763c23a9a8378aad784fef247ff2971360..72efd73750906e43ef69408851eb563887c12ffb 100644
--- a/src/plat/odroidc2/overlay-odroidc2.dts
+++ b/src/plat/odroidc2/overlay-odroidc2.dts
@@ -12,6 +12,10 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial0",
+ &{/psci};
+
seL4,kernel-devices =
"serial0",
&{/soc/interrupt-controller@c4301000},
diff --git a/src/plat/omap3/overlay-omap3.dts b/src/plat/omap3/overlay-omap3.dts
index d80883782115d8c3da618aa788b83fdac7391aeb..725a2fa30638beec6d7152c2948e4ee6b8e9de36 100644
--- a/src/plat/omap3/overlay-omap3.dts
+++ b/src/plat/omap3/overlay-omap3.dts
@@ -13,6 +13,8 @@
/ {
chosen {
stdout-path = "serial2";
+ seL4,elfloader-devices =
+ "serial2";
seL4,kernel-devices =
"serial2",
&{/ocp@68000000/interrupt-controller@48200000},
diff --git a/src/plat/qemu-arm-virt/overlay-qemu-arm-virt.dts b/src/plat/qemu-arm-virt/overlay-qemu-arm-virt.dts
index 9fa1e5ab1004c9240a4946847dfd1a4fc6535aa3..176487bcd30fcc219d8d6b8b896f96d986f12e16 100644
--- a/src/plat/qemu-arm-virt/overlay-qemu-arm-virt.dts
+++ b/src/plat/qemu-arm-virt/overlay-qemu-arm-virt.dts
@@ -12,6 +12,9 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ &{/pl011@9000000},
+ &{/psci};
seL4,kernel-devices =
&{/pl011@9000000},
&{/intc@8000000},
diff --git a/src/plat/rockpro64/overlay-rockpro64.dts b/src/plat/rockpro64/overlay-rockpro64.dts
index 388dd3aa850a3486214d43a2cbbb4c4403cc2c63..046ed72debfe376340e2f1efa5126e84f3c1fdcb 100644
--- a/src/plat/rockpro64/overlay-rockpro64.dts
+++ b/src/plat/rockpro64/overlay-rockpro64.dts
@@ -12,6 +12,9 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial2",
+ &{/psci};
seL4,kernel-devices =
"serial2",
&{/interrupt-controller@fee00000},
diff --git a/src/plat/tk1/overlay-tk1.dts b/src/plat/tk1/overlay-tk1.dts
index 64c1bb73e5b756c74290045e0a8837812010e905..e2d71aa37552676a5e249145a41d112bd1e4d3fc 100644
--- a/src/plat/tk1/overlay-tk1.dts
+++ b/src/plat/tk1/overlay-tk1.dts
@@ -12,6 +12,8 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial0";
seL4,kernel-devices =
"serial0",
&{/interrupt-controller@50041000},
diff --git a/src/plat/tx1/overlay-tx1.dts b/src/plat/tx1/overlay-tx1.dts
index 733aec786582a0cd483d292c5f631665fa5fb6e1..f4d47b59ef1e8738edeb4e2771dd94450097a84c 100644
--- a/src/plat/tx1/overlay-tx1.dts
+++ b/src/plat/tx1/overlay-tx1.dts
@@ -12,6 +12,10 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial0",
+ &{/psci};
+
seL4,kernel-devices =
"serial0",
&{/interrupt-controller@50041000},
diff --git a/src/plat/tx2/overlay-tx2.dts b/src/plat/tx2/overlay-tx2.dts
index 8d2ca52869d5ac43a68a1159ca8e3dbcc8edc54e..d375d7074ce28c2eb7807eb8f4e0c0b5fba20694 100644
--- a/src/plat/tx2/overlay-tx2.dts
+++ b/src/plat/tx2/overlay-tx2.dts
@@ -14,6 +14,9 @@
/* seL4 on the TX2 boots on the first non-NVIDIA core */
chosen {
seL4,boot-cpu = <&{/cpus/cpu@2}>;
+ seL4,elfloader-devices =
+ "serial0",
+ &{/psci};
seL4,kernel-devices =
"serial0",
&{/interrupt-controller@3881000},
diff --git a/src/plat/zynq7000/overlay-zynq7000.dts b/src/plat/zynq7000/overlay-zynq7000.dts
index 7eae7b89439caa6930222973b0f1181552790660..7896543a930583acfd1b06fc8732e2dc4fe1af78 100644
--- a/src/plat/zynq7000/overlay-zynq7000.dts
+++ b/src/plat/zynq7000/overlay-zynq7000.dts
@@ -12,6 +12,9 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial0",
+ &{/amba/slcr@f8000000/rstc@200};
seL4,kernel-devices =
"serial0",
&{/amba/interrupt-controller@f8f01000},
diff --git a/src/plat/zynqmp/overlay-zynqmp.dts b/src/plat/zynqmp/overlay-zynqmp.dts
index 00b276df20730d5879bf77703c95541ddc686c2b..48842af233ed77a49fe59e33bab23465f44dc914 100644
--- a/src/plat/zynqmp/overlay-zynqmp.dts
+++ b/src/plat/zynqmp/overlay-zynqmp.dts
@@ -12,6 +12,9 @@
/ {
chosen {
+ seL4,elfloader-devices =
+ "serial0",
+ &{/psci};
seL4,kernel-devices =
"serial0",
&{/amba_apu@0/interrupt-controller@f9010000},
diff --git a/tools/hardware.yml b/tools/hardware.yml
index fbe210fa0b7ff79bb893d779a83beb1813252a0a..ee63d946be8741dec6474ca63e6ab8ed51b670af 100644
--- a/tools/hardware.yml
+++ b/tools/hardware.yml
@@ -238,3 +238,12 @@ devices:
regions:
- index: 0
kernel: PLIC_PPTR
+
+ # elfloader rules
+ - compatible:
+ - arm,psci-0.2
+ - arm,psci-1.0
+ - compatible:
+ - fsl,imx6q-src
+ - compatible:
+ - xlnx,zynq-reset
diff --git a/tools/hardware/device.py b/tools/hardware/device.py
index 365504aa5ca8dbf6b9ea5280d1fc70c07fa1843b..f6ce9ec0789141cd9ac56b7c6100c954e2cc686d 100644
--- a/tools/hardware/device.py
+++ b/tools/hardware/device.py
@@ -113,6 +113,11 @@ class WrappedNode:
reg.append(Region(self.parent._translate_child_address(r[0]), r[1], self))
return reg
+ def parse_address(self, array) -> int:
+ ''' parse a single address from the array. will pop values from the array '''
+ size = self.parent.get_addr_cells()
+ return Utils.make_number(size, array)
+
def get_interrupts(self, tree: 'FdtParser') -> List[int]:
irqs = []
if 'interrupts-extended' in self.props:
@@ -135,9 +140,12 @@ class WrappedNode:
def visit(self, visitor: Any):
''' Visit this node and all its children '''
- visitor(self)
+ ret = [visitor(self)]
+ if ret[0] is None:
+ ret = []
for child in self.children.values():
- child.visit(visitor)
+ ret += child.visit(visitor)
+ return ret
def __iter__(self) -> Generator['WrappedNode', None, None]:
''' Iterate over all immediate children of this node '''
diff --git a/tools/hardware/fdt.py b/tools/hardware/fdt.py
index 75a3f7704c22d3bfbf794c3e00726306641b4340..aa6b50dacaa27384dd40ef170affa93a44eb769c 100644
--- a/tools/hardware/fdt.py
+++ b/tools/hardware/fdt.py
@@ -79,13 +79,19 @@ class FdtParser:
return prop.strings[0]
def get_kernel_devices(self) -> List[WrappedNode]:
+ return self.get_devices_list('seL4,kernel-devices')
+
+ def get_elfloader_devices(self) -> List[WrappedNode]:
+ return self.get_devices_list('seL4,elfloader-devices')
+
+ def get_devices_list(self, prop) -> List[WrappedNode]:
''' Returns a list of devices that are used by the kernel '''
chosen = self.get_path('/chosen')
- if not chosen.has_prop('seL4,kernel-devices'):
+ if not chosen.has_prop(prop):
return []
ret = []
- paths = chosen.get_prop('seL4,kernel-devices').strings
+ paths = chosen.get_prop(prop).strings
for path in paths:
if path[0] != '/':
@@ -104,4 +110,4 @@ class FdtParser:
def visit(self, visitor: Any):
''' Walk the tree, calling the given visitor function on each node '''
- self.wrapped_root.visit(visitor)
+ return self.wrapped_root.visit(visitor)
diff --git a/tools/hardware/outputs/elfloader.py b/tools/hardware/outputs/elfloader.py
index cabfc95b9792d7b61983e9a970f315a42aa1946a..10a994b2550b98f433ce2cec294f6270dfb45f53 100644
--- a/tools/hardware/outputs/elfloader.py
+++ b/tools/hardware/outputs/elfloader.py
@@ -18,9 +18,10 @@ import logging
import pyfdt.pyfdt
from jinja2 import Environment, BaseLoader
+from typing import List
-from hardware import config, fdt
-from hardware.utils import memory, rule
+from hardware import config, device, fdt
+from hardware.utils import cpu, memory, rule
HEADER_TEMPLATE = '''/*
@@ -40,6 +41,11 @@ HEADER_TEMPLATE = '''/*
#pragma once
+#include <types.h>
+{% if uses_psci %}
+#include <psci.h>
+{% endif %}
+
#define MAX_NUM_REGIONS {{ max_reg }}
struct elfloader_driver;
@@ -50,6 +56,13 @@ struct elfloader_device {
struct elfloader_driver *drv;
};
+struct elfloader_cpu {
+ const char *compat;
+ const char *enable_method;
+ word_t cpu_id;
+ word_t extra_data;
+};
+
#ifdef DRIVER_COMMON
struct elfloader_device elfloader_devices[] = {
{% for d in devices %}
@@ -77,33 +90,73 @@ struct elfloader_device elfloader_devices[] = {
},
{% endif %}
};
+
+struct elfloader_cpu elfloader_cpus[] = {
+ {% for cpu in cpus %}
+ {
+ /* {{ cpu['path'] }} */
+ .compat = "{{ cpu['compat'] }}",
+ .enable_method = {{ '"{}"'.format(cpu['enable_method']) if cpu['enable_method'] else 'NULL' }},
+ .cpu_id = {{ "0x{:x}".format(cpu['cpuid']) }},
+ .extra_data = {{ cpu['extra'] }}
+ },
+ {% endfor %}
+ { .compat = NULL /* sentinel */ },
+};
#else
-struct elfloader_device *elfloader_devices;
+extern struct elfloader_device elfloader_devices[];
+extern struct elfloader_cpu elfloader_cpus[];
#endif
'''
-def get_elfloader_devices(tree: fdt.FdtParser, rules: rule.HardwareYaml):
- devices = []
+def get_elfloader_cpus(tree: fdt.FdtParser, devices: List[device.WrappedNode]) -> List[dict]:
+ cpus = cpu.get_cpus(tree)
+ PSCI_COMPAT = ['arm,psci-0.2', 'arm,psci-1.0']
+ psci_node = [n for n in devices if n.has_prop('compatible')
+ and n.get_prop('compatible').strings[0] in PSCI_COMPAT]
- # serial device
- chosen = tree.get_path('/chosen')
- if not chosen.has_prop('stdout-path') or type(chosen.get_prop('stdout-path')) != pyfdt.pyfdt.FdtPropertyStrings:
- logging.info('DT has no stdout-path, elfloader may not produce output!')
+ if len(psci_node) > 0:
+ psci_node = psci_node[0]
else:
- val = chosen.get_prop('stdout-path').strings[0]
- if val[0] == '/':
- path = val
- else:
- path = tree.lookup_alias(val)
- devices.append(tree.get_path(path))
- return devices
+ psci_node = None
+
+ cpu_info = []
+ for i, cpu_node in enumerate(sorted(cpus, key=lambda a: a.path)):
+ enable_method = None
+ if cpu_node.has_prop('enable-method'):
+ enable_method = cpu_node.get_prop('enable-method').strings[0]
+
+ cpuid = i
+ if cpu_node.has_prop('reg'):
+ cpuid = cpu_node.parse_address(list(cpu_node.get_prop('reg').words))
+
+ extra_data = 0
+ if enable_method == 'psci' and psci_node:
+ extra_data = 'PSCI_METHOD_' + psci_node.get_prop('method').strings[0].upper()
+ elif enable_method == 'spin-table':
+ extra_data = '0x{:x}'.format(
+ device.Utils.make_number(2, list(cpu_node.get_prop('cpu-release-addr').words)))
+
+ obj = {
+ 'compat': cpu_node.get_prop('compatible').strings[0],
+ 'enable_method': enable_method,
+ 'cpuid': cpuid,
+ 'path': cpu_node.path,
+ 'extra': extra_data,
+ }
+ cpu_info.append(obj)
+
+ # guarantee that cpus in the same cluster will be consecutive
+ return sorted(cpu_info, key=lambda a: a['cpuid'])
def run(tree: fdt.FdtParser, hardware: rule.HardwareYaml, config: config.Config, args: argparse.Namespace):
- devices = get_elfloader_devices(tree, hardware)
- device_info = []
+ devices = tree.get_elfloader_devices()
+ cpu_info = get_elfloader_cpus(tree, devices)
+
max_reg = 1
+ device_info = []
for dev in devices:
obj = {
'compat': hardware.get_matched_compatible(dev),
@@ -120,8 +173,10 @@ def run(tree: fdt.FdtParser, hardware: rule.HardwareYaml, config: config.Config,
lstrip_blocks=True).from_string(HEADER_TEMPLATE)
template_args = dict(builtins.__dict__, **{
+ 'cpus': cpu_info,
'devices': device_info,
- 'max_reg': max_reg
+ 'max_reg': max_reg,
+ 'uses_psci': any([c['enable_method'] == 'psci' for c in cpu_info])
})
data = template.render(template_args)
diff --git a/tools/hardware/utils/cpu.py b/tools/hardware/utils/cpu.py
new file mode 100644
index 0000000000000000000000000000000000000000..5795e8e0cdf56d9fd96444650f2364b8000f6c0e
--- /dev/null
+++ b/tools/hardware/utils/cpu.py
@@ -0,0 +1,30 @@
+#
+# Copyright 2019, Data61
+# Commonwealth Scientific and Industrial Research Organisation (CSIRO)
+# ABN 41 687 119 230.
+#
+# This software may be distributed and modified according to the terms of
+# the GNU General Public License version 2. Note that NO WARRANTY is provided.
+# See "LICENSE_GPLv2.txt" for details.
+#
+# @TAG(DATA61_GPL)
+#
+from typing import List
+
+from hardware.device import WrappedNode
+from hardware.fdt import FdtParser
+
+# documentation for CPU bindings:
+# https://www.kernel.org/doc/Documentation/devicetree/bindings/arm/cpus.yaml
+
+
+def get_cpus(tree: FdtParser) -> List[WrappedNode]:
+ ' Return a list of all the CPUs described in this device tree. '
+ cpus_node = tree.get_path('/cpus')
+
+ found_cpus = []
+ for node in cpus_node:
+ if node.has_prop('device_type') and node.get_prop('device_type').strings[0] == 'cpu':
+ found_cpus.append(node)
+
+ return found_cpus