Commit b1f1e9dcfa renamed 'riscv,delegate' to 'riscv,delegation' since
it is the correct name as per dt-bindings, and the absence of the
correct name will result in validation fails when dumping the dtb and
using dt-validate.
But this change has a side-effect: every other firmware available that
is AIA capable is using 'riscv,delegate', and it will fault/misbehave if
this property isn't present. The property was added back in QEMU 7.0,
meaning we have 2 years of firmware development using the wrong
property.
Re-introducing 'riscv,delegate' while keeping 'riscv,delegation' will
make current firmwares to keep booting with the 'virt' machine and
dt-validate won't complain about it since we're still using the expected
property 'riscv,delegation'. 'riscv,delegate' is then marked for future
deprecation and its use is being discouraged.
Cc: Conor Dooley <co...@kernel.org>
Cc: Anup Patel <apa...@ventanamicro.com>
Fixes: b1f1e9dcfa ("hw/riscv/virt.c: aplic DT: rename prop to 'riscv,
delegation'")
Signed-off-by: Daniel Henrique Barboza <dbarb...@ventanamicro.com>
---
docs/about/deprecated.rst | 11 +++++++++++
hw/riscv/virt.c | 9 +++++++++
2 files changed, 20 insertions(+)
diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
index 20b7a17cf0..88f0f03786 100644
--- a/docs/about/deprecated.rst
+++ b/docs/about/deprecated.rst
@@ -479,6 +479,17 @@ versions, aliases will point to newer CPU model versions
depending on the machine type, so management software must
resolve CPU model aliases before starting a virtual machine.
+RISC-V "virt" board "riscv,delegate" DT property (since 9.1)
+''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
+
+The "riscv,delegate" DT property was added in QEMU 7.0 as part of
+the AIA APLIC support. The property changed name during the review
+process in Linux and the correct name ended up being
+"riscv,delegation". Changing the DT property name will break all
+available firmwares that are using the current (wrong) name. The
+property is kept as is in 9.1, together with "riscv,delegation", to
+give more time for firmware developers to change their code.
+
Migration
---------
diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
index bc0893e087..9981e0f6c9 100644
--- a/hw/riscv/virt.c
+++ b/hw/riscv/virt.c
@@ -651,6 +651,15 @@ static void create_fdt_one_aplic(RISCVVirtState *s, int
socket,
qemu_fdt_setprop_cells(ms->fdt, aplic_name, "riscv,delegation",
aplic_child_phandle, 0x1,
VIRT_IRQCHIP_NUM_SOURCES);
+ /*
+ * DEPRECATED_9.1: Compat property kept temporarily
+ * to allow old firmwares to work with AIA. Do *not*
+ * use 'riscv,delegate' in new code: use
+ * 'riscv,delegation' instead.
+ */
+ qemu_fdt_setprop_cells(ms->fdt, aplic_name, "riscv,delegate",
+ aplic_child_phandle, 0x1,
+ VIRT_IRQCHIP_NUM_SOURCES);
}
riscv_socket_fdt_write_id(ms, aplic_name, socket);
--
2.45.2
