Antwort: [PATCH v2] serial: ns16550: Fix ordering of getting base address

Wolfgang Wallner wolfgang.wallner at
Fri Apr 3 15:01:29 CEST 2020

Hi Bin,

-----"Bin Meng" < at> schrieb: -----
>Betreff: [PATCH v2] serial: ns16550: Fix ordering of getting base
>Currently the driver gets ns16550 base address in the driver
>probe() routine, which may potentially break any ns16550 wrapper
>driver that does additional initialization before calling
>Things are complicated that we need consider ns16550 devices on
>both simple-bus and PCI bus. To fix the issue we move the base
>address assignment for simple-bus ns16550 device back to the
>ofdata_to_platdata(), and assign base address for PCI ns16550
>device in ns16550_serial_probe().
>This is still not perfect. Ideally if any PCI bus based ns16550
>wrapper driver tries to access plat->base before calling probe(),
>it is subject to break.
>Fixes: 720f9e1fdb0c9 ("serial: ns16550: Move PCI access from
>ofdata_to_platdata() to probe()")
>Reported-by: Andy Shevchenko <andriy.shevchenko at>
>Signed-off-by: Bin Meng < at>
>Tested-by: Andy Shevchenko <andriy.shevchenko at>
>Reviewed-by: Wolfgang Wallner <wolfgang.wallner at>
>Tested-by: Wolfgang Wallner <wolfgang.wallner at>
>Changes in v2:
>- not to break Fixes, etc to two or more lines in the commit message
>- add the same CONFIG_SYS_NS16550_PORT_MAPPED ifdefs in the PCI case
> drivers/serial/ns16550.c | 53
> 1 file changed, 27 insertions(+), 26 deletions(-)

I have also tested v2, just to be sure.
Works as expected.

regards, Wolfgang

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