diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2025-10-24 15:46:21 -0700 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2025-10-28 12:36:34 -0500 |
| commit | bcce8c74f1ce1e2731ac0261287897e3768767d8 (patch) | |
| tree | dc29b2f93bbd5c82ac2a7532955db50af85f14ba /drivers/pci/controller/dwc/pcie-qcom-common.c | |
| parent | 3a8660878839faadb4f1a6dd72c3179c1df56787 (diff) | |
PCI: Enable host bridge emulation for PCI_DOMAINS_GENERIC platforms
The ability to emulate a host bridge is useful not only for hardware PCI
controllers like CONFIG_VMD, or virtual PCI controllers like
CONFIG_PCI_HYPERV, but also for test and development scenarios like
CONFIG_SAMPLES_DEVSEC [1].
One stumbling block for defining CONFIG_SAMPLES_DEVSEC, a sample
implementation of a platform TSM for PCI Device Security, is the need to
accommodate PCI_DOMAINS_GENERIC architectures alongside x86 [2].
In support of supplementing the existing CONFIG_PCI_BRIDGE_EMUL
infrastructure for host bridges:
* Introduce pci_bus_find_emul_domain_nr() as a common way to find a free
PCI domain number whether that is to reuse the existing dynamic
allocation code in the !ACPI case, or to assign an unused domain above
the last ACPI segment.
* Convert pci-hyperv to the new allocator so that the PCI core can
unconditionally assume that bridge->domain_nr != PCI_DOMAIN_NR_NOT_SET
is the dynamically allocated case.
A follow on patch can also convert vmd to the new scheme. Currently vmd is
limited to CONFIG_PCI_DOMAINS_GENERIC=n (x86) so, unlike pci-hyperv, it
does not immediately conflict with this new pci_bus_find_emul_domain_nr()
mechanism.
Link: http://lore.kernel.org/174107249038.1288555.12362100502109498455.stgit@dwillia2-xfh.jf.intel.com [1]
Reported-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Closes: http://lore.kernel.org/20250311144601.145736-3-suzuki.poulose@arm.com [2]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Rob Herring <robh@kernel.org>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Dexuan Cui <decui@microsoft.com>
Link: https://patch.msgid.link/20251024224622.1470555-2-dan.j.williams@intel.com
Diffstat (limited to 'drivers/pci/controller/dwc/pcie-qcom-common.c')
0 files changed, 0 insertions, 0 deletions