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| author | Alexey Brodkin <Alexey.Brodkin@synopsys.com> | 2014-02-08 10:10:01 +0400 |
|---|---|---|
| committer | Tom Rini <trini@ti.com> | 2014-02-21 07:54:05 -0500 |
| commit | 1d568c7666e81fa920de38a3c83895764ea8cf0f (patch) | |
| tree | bd6cf473cb378c4355e65f9d579a0c2c0af4a4a5 /drivers/serial/serial_arc.c | |
| parent | 6853e6aa77b388998a5368b400aee3ae7776b1c2 (diff) | |
| download | u-boot-imx-1d568c7666e81fa920de38a3c83895764ea8cf0f.zip u-boot-imx-1d568c7666e81fa920de38a3c83895764ea8cf0f.tar.gz u-boot-imx-1d568c7666e81fa920de38a3c83895764ea8cf0f.tar.bz2 | |
serial/serial_arc: add work-around of ISS bug
Explanation is in in-lined comment.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Tom Rini <trini@ti.com>
Diffstat (limited to 'drivers/serial/serial_arc.c')
| -rw-r--r-- | drivers/serial/serial_arc.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/serial/serial_arc.c b/drivers/serial/serial_arc.c index e63d25d..55d0769 100644 --- a/drivers/serial/serial_arc.c +++ b/drivers/serial/serial_arc.c @@ -39,7 +39,23 @@ static void arc_serial_setbrg(void) arc_console_baud = gd->cpu_clk / (gd->baudrate * 4) - 1; writel(arc_console_baud & 0xff, ®s->baudl); + +#ifdef CONFIG_ARC + /* + * UART ISS(Instruction Set simulator) emulation has a subtle bug: + * A existing value of Baudh = 0 is used as a indication to startup + * it's internal state machine. + * Thus if baudh is set to 0, 2 times, it chokes. + * This happens with BAUD=115200 and the formaula above + * Until that is fixed, when running on ISS, we will set baudh to !0 + */ + if (gd->arch.running_on_hw) + writel((arc_console_baud & 0xff00) >> 8, ®s->baudh); + else + writel(1, ®s->baudh); +#else writel((arc_console_baud & 0xff00) >> 8, ®s->baudh); +#endif } static int arc_serial_init(void) |