commit eb6c3ba1d42fd087708f568ca220ff557f22104e
Author: Jakob Haufe <sur5r@sur5r.net>
Date:   Tue Jun 17 13:58:19 2025 +0200

    MIPS: OCTEON: Add UBNT specific DTS pruning
    
    This imports device specific DTS pruning from
    https://github.com/UI-Packages/kernel_e200/blob/master/arch/mips/cavium-octeon/octeon-platform.c#L1067
    
    - Reduce MMC clock frequency on E200/E220 to make
      MMC communication reliable again. See linked issue.
    - Remove unused MMC node on E300.
    
    Related: https://github.com/openwrt/openwrt/issues/13762
    
    Signed-off-by: Jakob Haufe <sur5r@sur5r.net>

--- a/arch/mips/cavium-octeon/octeon-platform.c
+++ b/arch/mips/cavium-octeon/octeon-platform.c
@@ -1133,6 +1133,41 @@ end_led:
 	}
 #endif
 
+
+	return 0;
+}
+
+int __init ubnt_prune_device_tree(void)
+{
+	/* MMC on UBNT */
+	pr_info("UBNT board DTS pruning...\n");
+	if (octeon_bootinfo->board_type == CVMX_BOARD_TYPE_UBNT_E300) {
+		pr_info("UBNT E300 found, looking for mmc-slot@2\n");
+		// Remove unused MMC slot definition
+		int mmc_slot2 = fdt_path_offset(initial_boot_params, "/soc/mmc/mmc-slot@2");
+
+		if (mmc_slot2 > 0) {
+			pr_info("UBNT E300 found, deleting mmc-slot@2\n");
+			fdt_nop_node(initial_boot_params, mmc_slot2);
+		} else {
+			pr_info("mmc-slot@2 not found\n");
+		}
+	} else if (octeon_bootinfo->board_type == CVMX_BOARD_TYPE_UBNT_E200 ||
+		   octeon_bootinfo->board_type == CVMX_BOARD_TYPE_UBNT_E220) {
+		pr_info("UBNT E200/E220 found, looking for mmc-slot@0\n");
+		int mmc_slot0 = fdt_path_offset(initial_boot_params, "/soc/mmc/mmc-slot@0");
+
+		u32 freq = 26000000;
+
+		if (mmc_slot0 > 0) {
+			pr_info("UBNT E200/E220 mmc-slot@0 found, setting frequency to 26MHz");
+			fdt_setprop_inplace_cell(initial_boot_params, mmc_slot0,
+						 "spi-max-frequency", freq);
+		} else {
+			pr_info("mmc-slot@0 not found\n");
+		}
+	}
+
 	return 0;
 }
 
--- a/arch/mips/cavium-octeon/setup.c
+++ b/arch/mips/cavium-octeon/setup.c
@@ -1168,6 +1168,7 @@ void __init prom_free_prom_memory(void)
 	}
 }
 
+int __init ubnt_prune_device_tree(void);
 void __init octeon_fill_mac_addresses(void);
 
 void __init device_tree_init(void)
@@ -1207,6 +1208,9 @@ void __init device_tree_init(void)
 		octeon_prune_device_tree();
 		pr_info("Using internal Device Tree.\n");
 	}
+
+	ubnt_prune_device_tree();
+
 	if (fill_mac)
 		octeon_fill_mac_addresses();
 	unflatten_and_copy_device_tree();