On Sat, Aug 17, 2024 at 2:08 AM Andrew Jones <ajo...@ventanamicro.com> wrote: > > Older firmwares and OS kernels which use deprecated device tree > properties or are missing support for new properties may not be > tolerant of fully compliant device trees. When divergence to the > bindings specifications is harmless for new firmwares and OS kernels > which are compliant, then it's probably better to also continue > supporting the old firmwares and OS kernels by generating > non-compliant device trees. The '#msi-cells=<0>' property of the > imsic is one such property. Generating that property doesn't provide > anything necessary (no '#msi-cells' property or an '#msi-cells' > property with a value of zero mean the same thing) but it does > cause PCI devices to fail to find the MSI controller on Linux and, > for that reason, riscv virt doesn't currently generate it despite > that putting the DT out of compliance. For users that want a > compliant DT and know their software supports it, introduce a machine > property 'strict-dt' to do so. We also drop the one redundant > property that uses a deprecated name when strict-dt is enabled. > > Signed-off-by: Andrew Jones <ajo...@ventanamicro.com> > --- > docs/system/riscv/virt.rst | 11 ++++++++++ > hw/riscv/virt.c | 43 ++++++++++++++++++++++++++++++-------- > include/hw/riscv/virt.h | 1 + > 3 files changed, 46 insertions(+), 9 deletions(-) > > diff --git a/docs/system/riscv/virt.rst b/docs/system/riscv/virt.rst > index 9a06f95a3444..f08d0a053051 100644 > --- a/docs/system/riscv/virt.rst > +++ b/docs/system/riscv/virt.rst > @@ -116,6 +116,17 @@ The following machine-specific options are supported: > having AIA IMSIC (i.e. "aia=aplic-imsic" selected). When not specified, > the default number of per-HART VS-level AIA IMSIC pages is 0. > > +- strict-dt=[on|off]
Hmm... I don't love the idea of having yet another command line option. Does this really buy us a lot? Eventually we should deprecate the invalid DT bindings anyway Alistair
