Messages in this thread | | | Date | Fri, 6 Dec 2013 13:42:11 +1100 | From | James Cameron <> | Subject | Re: [PATCH] serial: rewrite pxa2xx-uart to use 8250_core |
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On Fri, Dec 06, 2013 at 03:28:37AM +0400, Sergei Ianovich wrote: > pxa2xx-uart was a separate uart platform driver. It was declaring > the same device names and numbers as 8250 driver. As a result, > it was impossible to use 8250 driver on PXA SoCs. > > Upon closer examination pxa2xx-uart turned out to be a clone of > 8250_core driver.
[...]
> +/* Uart divisor latch write */ > +static void serial_pxa_dl_write(struct uart_8250_port *up, int value) > +{ > + serial_out(up, UART_DLL, value & 0xff); > + serial_out(up, UART_DLM, value >> 8 & 0xff); > +}
This is a change. drivers/tty/serial/pxa.c did read back UART_DLL as an errata work around:
> - /* > - * work around Errata #75 according to Intel(R) PXA27x Processor Family > - * Specification Update (Nov 2005) > - */ > - dll = serial_in(up, UART_DLL); > - WARN_ON(dll != (quot & 0xff));
If this is no longer needed, serial_pxa_dl_write can be removed because it is same as default_serial_dl_write.
I did not check the other errata work arounds.
-- James Cameron http://quozl.linux.org.au/
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