BeagleV-Fire Cape_4_Uarts only has 3 UARTs showing up in Linux

BeagleV
,
1

I’m using the CAPE_4_UARTS cape option, and in the device tree overlay file, I see that there are 4 UARTS specified as follows:

&mmuart1 {
	status = "okay";
	symlink = "bone/uart/5";
};

&mmuart2 {
	status = "okay";
	symlink = "bone/uart/1";
};

&mmuart3 {
	status = "okay";
	symlink = "bone/uart/2";
};

&mmuart4 {
	status = "okay";
	symlink = "bone/uart/4";
};

However, when I do the build, I only see three of them show up as valid ports in /dev/bone/uart:

beagle@BeagleV:/dev/bone/uart$ ll
total 4
drwxr-xr-x 2 root root 120 Mar 18 19:32 ./
drwxr-xr-x 7 root root 140 Mar 18 19:32 ../
lrwxrwxrwx 1 root root  11 Sep 19  2023 1 -> ../../ttyS2
lrwxrwxrwx 1 root root  11 Sep 19  2023 2 -> ../../ttyS3
lrwxrwxrwx 1 root root  11 Sep 19  2023 5 -> ../../ttyS1
-rw-r--r-- 1 root root 344 Mar 18 19:32 README.md
beagle@BeagleV:/dev/bone/uart$

I have looked in the Libero project, and it appears to me that all 4 UARTS that route through FPGA fabric (MMUART_1 through MMUART_4) are enabled, and are routed to the pins as expected:

image
image587×496 41.8 KB

The three UARTs that show up are working as expected. Is there something else I need to do to get the fourth UART working?