FAILED: Patch "MIPS: rb532: Fix MMIO UART resource registration" failed to apply to 5.15-stable tree

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From e93bb4b76cfefb302534246e892c7667491cb8cc Mon Sep 17 00:00:00 2001
From: Jiaxun Yang <[email protected]>
Date: Thu, 5 Feb 2026 10:08:42 +0000
Subject: [PATCH] MIPS: rb532: Fix MMIO UART resource registration

Since commit 6e690d54cfa8 ("serial: 8250: fix return error code in serial8250_request_std_resource()"), registering an 8250 MMIO port without mapbase no longer works, as the resource range is derived from mapbase/mapsize.

Populate mapbase and mapsize accordingly. Also drop ugly membase KSEG1 pointer and set UPF_IOREMAP instead, letting the 8250 core perform the ioremap.

---
 arch/mips/rb532/devices.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

index b7f6f782d9a13..ffa4d38ca95df 100644
@@ -212,11 +212,12 @@ static struct platform_device rb532_wdt = {
 static struct plat_serial8250_port rb532_uart_res[] = {
 	{
 		.type           = PORT_16550A,
-		.membase	= (char *)KSEG1ADDR(REGBASE + UART0BASE),
+		.mapbase        = REGBASE + UART0BASE,
+		.mapsize        = 0x1000,
 		.irq		= UART0_IRQ,
 		.regshift	= 2,
 		.iotype		= UPIO_MEM,
-		.flags		= UPF_BOOT_AUTOCONF,
+		.flags		= UPF_BOOT_AUTOCONF | UPF_IOREMAP,
 	},
 	{
 		.flags		= 0,

2.51.0