dm, serial: problem with using ns16550 driver before relocation on mpc83xx

Heiko Schocher hs at denx.de
Wed Feb 5 10:04:32 CET 2020


Hello Bin, Simon,

I just porting the mpc83xx based kmcoge5ne board support DTS and got
problems using the serial ns16550 driver.

I need the serial driver before rolcation, so I enabled
"u-boot,dm-pre-reloc;" as usual in the device tree, but board does not
boot ...

I found the commit:

commit 4687919684e0e4390b9fc20d1809ecaa9dc3cb81
Author: Bin Meng <bmeng.cn at gmail.com>
Date:   Wed Oct 24 06:36:36 2018 -0700

     serial: Remove DM_FLAG_PRE_RELOC flag in various drivers

which added to the ns16550 serial driver:

diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c
index 04b604fa2c..1e6fc6c668 100644
--- a/drivers/serial/ns16550.c
+++ b/drivers/serial/ns16550.c
@@ -487,7 +487,9 @@ U_BOOT_DRIVER(ns16550_serial) = {
         .priv_auto_alloc_size = sizeof(struct NS16550),
         .probe = ns16550_serial_probe,
         .ops    = &ns16550_serial_ops,
+#if !CONFIG_IS_ENABLED(OF_CONTROL)
         .flags  = DM_FLAG_PRE_RELOC,
+#endif
  };
  #endif
  #endif /* SERIAL_PRESENT */

So, as OF_CONTROL is defined for me, the flag "u-boot,dm-pre-reloc" seems
not working anymore ...

Adding this back:

hs at xmglap:u-boot-secu  [20200205-temp] $ git diff
diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c
index 9851663dc5..386ca9cffa 100644
--- a/drivers/serial/ns16550.c
+++ b/drivers/serial/ns16550.c
@@ -528,7 +528,7 @@ U_BOOT_DRIVER(ns16550_serial) = {
         .priv_auto_alloc_size = sizeof(struct NS16550),
         .probe = ns16550_serial_probe,
         .ops    = &ns16550_serial_ops,
-#if !CONFIG_IS_ENABLED(OF_CONTROL)
+#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
         .flags  = DM_FLAG_PRE_RELOC,
  #endif
  };

and board boots fine with the flag "u-boot,dm-pre-reloc" in DTS ...

May I do something wrong here? I found in mainline for example
the "arch/powerpc/dts/gdsys/gazerbeam-uboot.dtsi" board, which
has the exactly same dts settings than I have now.

@Dirk: Can you check, if this board boots with current mainline?

Shouldn;t be the logic, that in case OF_CONTROL is enabled and if
flag "u-boot,dm-pre-reloc" is set in DTS for the device, the device
should be bound before relocation, and we do not need to check, if
the driver sets DM_FLAG_PRE_RELOC ?

But may I miss here something ...

Any hints?

bye,
Heiko
-- 
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