[ARM] pxa/zeus: relax memory timings on Zeus ethernet ports
Marc Zyngier [Sat, 26 Dec 2009 20:24:12 +0000 (21:24 +0100)]
DM9000s on Zeus sometime fail under heavy load.
Relaxing the timings a bit seems to be of a great help.

Signed-off-by: Marc Zyngier <maz@misterjones.org>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>

arch/arm/mach-pxa/zeus.c

index 865df5d..2f480a2 100644 (file)
@@ -726,9 +726,18 @@ static mfp_cfg_t zeus_pin_config[] __initdata = {
        GPIO99_GPIO,            /* CF RDY */
 };
 
+/*
+ * DM9k MSCx settings: SRAM, 16 bits
+ *                     17 cycles delay first access
+ *                      5 cycles delay next access
+ *                     13 cycles recovery time
+ *                     faster device
+ */
+#define DM9K_MSC_VALUE         0xe4c9
+
 static void __init zeus_init(void)
 {
-       u16 dm9000_msc = 0xe279;
+       u16 dm9000_msc = DM9K_MSC_VALUE;
 
        system_rev = __raw_readw(ZEUS_CPLD_VERSION);
        pr_info("Zeus CPLD V%dI%d\n", (system_rev & 0xf0) >> 4, (system_rev & 0x0f));