SMBIOS/SCONFIG: Allow devtree-defined Type 41 entries
Introduce the `smbios_dev_info` devicetree keyword to specify the
instance ID and RefDes (Reference Designation) of onboard devices.
Example syntax:
device pci 1c.0 on # PCIe Port #1
device pci 00.0 on
smbios_dev_info 6
end
end
device pci 1c.1 on # PCIe Port #2
device pci 00.0 on
smbios_dev_info 42 "PCIe-PCI Time Machine"
end
end
The `SMBIOS_TYPE41_PROVIDED_BY_DEVTREE` Kconfig option enables using
this syntax to control the generated Type 41 entries. When this option
is enabled, Type 41 entries are only autogenerated for devices with a
defined instance ID. This avoids having to keep track of which instance
IDs have been used for every device class.
Using `smbios_dev_info` when `SMBIOS_TYPE41_PROVIDED_BY_DEVTREE` is not
enabled will result in a build-time error, as the syntax is meaningless
in this case. This is done with preprocessor guards around the Type 41
members in `struct device` and the code which uses the guarded members.
Although the preprocessor usage isn't particularly elegant, adjusting
the devicetree syntax and/or grammar depending on a Kconfig option is
probably even worse.
Change-Id: Iecca9ada6ee1000674cb5dd7afd5c309d8e1a64b
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57370
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/src/Kconfig b/src/Kconfig
index be269b6..e4ddf0c 100644
--- a/src/Kconfig
+++ b/src/Kconfig
@@ -785,6 +785,21 @@
If unsure, say Y.
+config SMBIOS_TYPE41_PROVIDED_BY_DEVTREE
+ bool
+ depends on ARCH_X86
+ help
+ If enabled, only generate SMBIOS Type 41 entries for PCI devices in
+ the devicetree for which Type 41 information is provided, e.g. with
+ the `smbios_dev_info` devicetree syntax. This is useful to manually
+ assign specific instance IDs to onboard devices irrespective of the
+ device traversal order. It is assumed that instance IDs for devices
+ of the same class are unique.
+ When disabled, coreboot autogenerates SMBIOS Type 41 entries for all
+ appropriate PCI devices in the devicetree. Instance IDs are assigned
+ successive numbers from a monotonically increasing counter, with one
+ counter for each device class.
+
config SMBIOS_PROVIDED_BY_MOBO
bool
default n
diff --git a/src/arch/x86/smbios.c b/src/arch/x86/smbios.c
index ea42971..c05f905 100644
--- a/src/arch/x86/smbios.c
+++ b/src/arch/x86/smbios.c
@@ -1177,30 +1177,55 @@
}
}
+static bool smbios_get_type41_instance_id(struct device *dev, u8 device_type, u8 *instance_id)
+{
+#if CONFIG(SMBIOS_TYPE41_PROVIDED_BY_DEVTREE)
+ *instance_id = dev->smbios_instance_id;
+ return dev->smbios_instance_id_valid;
+#else
+ static u8 type41_inst_cnt[SMBIOS_DEVICE_TYPE_COUNT + 1] = {};
+
+ if (device_type == SMBIOS_DEVICE_TYPE_OTHER ||
+ device_type == SMBIOS_DEVICE_TYPE_UNKNOWN)
+ return false;
+
+ if (device_type > SMBIOS_DEVICE_TYPE_COUNT)
+ return false;
+
+ *instance_id = type41_inst_cnt[device_type]++;
+ return true;
+#endif
+}
+
+static const char *smbios_get_type41_refdes(struct device *dev)
+{
+#if CONFIG(SMBIOS_TYPE41_PROVIDED_BY_DEVTREE)
+ if (dev->smbios_refdes)
+ return dev->smbios_refdes;
+#endif
+ return get_pci_subclass_name(dev);
+}
+
static int smbios_generate_type41_from_devtree(struct device *dev, int *handle,
unsigned long *current)
{
- static u8 type41_inst_cnt[SMBIOS_DEVICE_TYPE_COUNT + 1] = {};
-
if (dev->path.type != DEVICE_PATH_PCI)
return 0;
if (!dev->on_mainboard)
return 0;
- u8 device_type = smbios_get_device_type_from_dev(dev);
+ const u8 device_type = smbios_get_device_type_from_dev(dev);
- if (device_type == SMBIOS_DEVICE_TYPE_OTHER ||
- device_type == SMBIOS_DEVICE_TYPE_UNKNOWN)
+ u8 instance_id;
+
+ if (!smbios_get_type41_instance_id(dev, device_type, &instance_id))
return 0;
- if (device_type > SMBIOS_DEVICE_TYPE_COUNT)
- return 0;
-
- const char *name = get_pci_subclass_name(dev);
+ const char *name = smbios_get_type41_refdes(dev);
return smbios_write_type41(current, handle,
name, // name
- type41_inst_cnt[device_type]++, // inst
+ instance_id, // inst
0, // segment
dev->bus->secondary, //bus
PCI_SLOT(dev->path.pci.devfn), // device
diff --git a/src/include/device/device.h b/src/include/device/device.h
index 8610e0a..237d836 100644
--- a/src/include/device/device.h
+++ b/src/include/device/device.h
@@ -148,6 +148,17 @@
u8 smbios_slot_data_width;
u8 smbios_slot_length;
const char *smbios_slot_designation;
+
+#if CONFIG(SMBIOS_TYPE41_PROVIDED_BY_DEVTREE)
+ /*
+ * These fields are intentionally guarded so that attempts to use
+ * the corresponding devicetree syntax without selecting the Kconfig
+ * option result in build-time errors. Smaller size is a side effect.
+ */
+ bool smbios_instance_id_valid;
+ u8 smbios_instance_id;
+ const char *smbios_refdes;
+#endif
#endif
#endif
DEVTREE_CONST void *chip_info;