diff mbox series

[PULL,12/18] hw/arm/virt: Add serial aliases in DTB

Message ID 20240622120643.3797539-13-peter.maydell@linaro.org
State Accepted
Commit 9ed2fb65cc827904241dee189c801c10079c2fe3
Headers show
Series [PULL,01/18] hw/net/can/xlnx-versal-canfd: Fix sorting of the tx queue | expand

Commit Message

Peter Maydell June 22, 2024, 12:06 p.m. UTC
If there is more than one UART in the DTB, then there is no guarantee
on which order a guest is supposed to initialise them.  The standard
solution to this is "serialN" entries in the "/aliases" node of the
dtb which give the nodename of the UARTs.

At the moment we only have two UARTs in the DTB when one is for
the Secure world and one for the Non-Secure world, so this isn't
really a problem. However if we want to add a second NS UART we'll
need the aliases to ensure guests pick the right one.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20240610162343.2131524-2-peter.maydell@linaro.org
---
 hw/arm/virt.c | 4 ++++
 1 file changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index c7a1f754e72..61a9d47c026 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -284,6 +284,8 @@  static void create_fdt(VirtMachineState *vms)
         }
     }
 
+    qemu_fdt_add_subnode(fdt, "/aliases");
+
     /* Clock node, for the benefit of the UART. The kernel device tree
      * binding documentation claims the PL011 node clock properties are
      * optional but in practice if you omit them the kernel refuses to
@@ -939,7 +941,9 @@  static void create_uart(const VirtMachineState *vms, int uart,
 
     if (uart == VIRT_UART) {
         qemu_fdt_setprop_string(ms->fdt, "/chosen", "stdout-path", nodename);
+        qemu_fdt_setprop_string(ms->fdt, "/aliases", "serial0", nodename);
     } else {
+        qemu_fdt_setprop_string(ms->fdt, "/aliases", "serial1", nodename);
         /* Mark as not usable by the normal world */
         qemu_fdt_setprop_string(ms->fdt, nodename, "status", "disabled");
         qemu_fdt_setprop_string(ms->fdt, nodename, "secure-status", "okay");