[PATCH] powerpc: serial port discovery: cope with broken firmware

On Tue, 2005-11-22 at 15:49 +1100, Benjamin Herrenschmidt wrote:
> This moves the discovery of legacy serial ports to a separate file,
> makes it common to ppc32 and ppc64, and reworks it to use the new OF
> address translators to get to the ports early. This new version can also
> detect some PCI serial cards using legacy chips and will probably match
> those discovered port with the default console choice.

This makes it deal with the fact that the Pegasos firmware reports that
its clock frequency is zero...
Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

arch/powerpc/kernel/legacy_serial.c

@@ -43,7 +43,10 @@ static int __init add_legacy_port(struct device_node *np, int want_index,
 
 	/* get clock freq. if present */
 	clk = (u32 *)get_property(np, "clock-frequency", NULL);
-	clock = clk ? *clk : BASE_BAUD * 16;
+	if (clk && *clk)
+		clock = *clk;
+	else
+		clock = BASE_BAUD * 16;
 
 	/* get default speed if present */
 	spd = (u32 *)get_property(np, "current-speed", NULL);