[PATCH v2 5/6] ARM: LPC32xx: serial.c: HW bug workaround

Roland Stigge stigge at antcom.de
Mon Feb 27 16:59:11 EST 2012


Hi!

On 27/02/12 20:02, Kevin Wells wrote:
> There isn't any errata related to this, but something strange was
> happening with the serial ports (only in Linux) if I didn't do this.
> I stumbled across a 'bug' comment in the pnx4008 port related to
> serial, tried the same fix, and the problem went away, so I
> (incorrectly) keyed in the errata wording.
> 
> Here's the original comment from the ARM pnx4008 port (serial.c):
>   48         /* Send a NULL to fix the UART HW bug */
>   49         __raw_writel(0x00, UART5_BASE_VA);
>   50         __raw_writel(0x00, UART3_BASE_VA);

Hard to trace since pnx4008's serial.c contains it since the beginning
in 2006.

OTOH, you added a bit more than this to lpc32xx' serial.c.

Anyway, I guess that PNX4008's and LPC3200's standard UARTs share some
ideas, NXP internally. ;-)

Roland



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