FAILED: patch "[PATCH] earlycon: add reg-offset to physical address before mapping" failed to apply to 4.9-stable tree

FAILED: patch "[PATCH] earlycon: add reg-offset to physical address before mapping" failed to apply to 4.9-stable tree

[gregkh]

The patch below does not apply to the 4.9-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 <stable@vger.kernel.org>.

thanks,

greg k-h

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

>From f572a034d9e07157dd07d2b6be3a1459b5574b58 Mon Sep 17 00:00:00 2001
From: Greentime Hu <greentime@andestech.com>
Date: Thu, 16 Nov 2017 19:33:35 +0800
Subject: [PATCH] earlycon: add reg-offset to physical address before mapping

It will get the wrong virtual address because port->mapbase is not added
the correct reg-offset yet. We have to update it before earlycon_map()
is called

Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Rob Herring <robh@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: stable@vger.kernel.org
Fixes: 088da2a17619 ("of: earlycon: Initialize port fields from DT
properties")

diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 870e84fb6e39..a24278380fec 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -245,11 +245,12 @@ int __init of_setup_earlycon(const struct earlycon_id *match,
 	}
 	port->mapbase = addr;
 	port->uartclk = BASE_BAUD * 16;
-	port->membase = earlycon_map(port->mapbase, SZ_4K);
 
 	val = of_get_flat_dt_prop(node, "reg-offset", NULL);
 	if (val)
 		port->mapbase += be32_to_cpu(*val);
+	port->membase = earlycon_map(port->mapbase, SZ_4K);
+
 	val = of_get_flat_dt_prop(node, "reg-shift", NULL);
 	if (val)
 		port->regshift = be32_to_cpu(*val);

Re: FAILED: patch "[PATCH] earlycon: add reg-offset to physical address before mapping" failed to apply to 4.9-stable tree

[Arnd Bergmann]

On Mon, Apr 16, 2018 at 12:13 PM,  <gregkh@linuxfoundation.org> wrote:
>
> The patch below does not apply to the 4.9-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 <stable@vger.kernel.org>.

I think we can do without it: there are only three machines that have
dt files with a reg-offset property in their uart:

- nds32 ae3xx was added in 4.17 and requires it there
- powerpc (virtex) has its own early console support and doesn't
  rely on earlycon.c
- mips (nexys4ddr) could use it, but has never made use of the
  earlycon driver in its DT files. It should now work out of the box
  in 4.17

       Arnd