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Date: Tue, 2 Jun 2009 10:24:15 -0300
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Subject: Re: MPC8343 - serial8250: too much work
From: Alemao <xcarandiru@gmail.com>
To: linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org
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Hi all,

In a normal situation, I have something like this:

serial8250_interrupt()
serial8250_handle_port()
transmit_chars()
pass_counter: 0
serial8250_handle_port()
pass_counter: 1
serial8250_handle_port()
pass_counter: 2
pass_counter: 3


But when the problem happends:

serial8250_interrupt(16)
serial8250_handle_port()
transmit_chars()
uart_circ_empty()
pass_counter: 0
.
.
.
serial8250_handle_port()
transmit_chars()
uart_circ_empty()
pass_counter: 257
serial8250: too much work for irq16

If the circ buffer is empty, why iterate 256 times?

How can I trace the application that is calling serial routines?

Its difficult to debug cause I use serial console to communicate with the board.

Thanks in advance,

--
Alemao