Re: N900 device tree conversion: how to do first step

[Pavel Machek <pavel@ucw.cz>]

On Sun 2013-06-09 11:24:40, Pali Rohár wrote:
> On Sunday 09 June 2013 03:59:44 Pavel Machek wrote:
> > Hi!
> > 
> > I'd like to convert Nokia N900 to device tree.
> > 
> > Unfortunately, serial port is not easily available (very
> > special cable would be needed, does someone know where to get
> > one?) and I don't have BDI (and very special cable would be
> > needed, too).
> > 
> 
> Hello,
> 
> I used serial port only in qemu for debugging. Maybe you can try
> to play with qemu first. Qemu has good n900 HW support.

Yes, qemu is helpful.

For the record: this is how you use it.

KERNEL=/data/l/linux-n900/zImage_dtb
./qflasher -m rx51 -x ./xloader-qemu.bin -s ./secondary-qemu.bin -k $KERNEL -o n900.img -p k=6072

> sd-empty
./qemu-system-arm -s -M n900 -mtdblock n900.img -sd sd-empty -serial
stdio -clock unix -redir tcp:5555:10.0.2.15:22

...and this patch is needed to make it past rx51_init.

Author: Pavel <pavel@ucw.cz>
Date:   Sun Jun 9 18:45:39 2013 +0200

    Comment out errata workaround that breaks qemu.

diff --git a/arch/arm/mach-omap2/board-rx51.c b/arch/arm/mach-omap2/board-rx51.c
index 938e46f..0ffd7d3 100644
--- a/arch/arm/mach-omap2/board-rx51.c
+++ b/arch/arm/mach-omap2/board-rx51.c
@@ -108,11 +108,13 @@ static void __init rx51_init(void)
 	rx51_peripherals_init();
 	rx51_camera_init();
 
+#if 0
 #ifdef CONFIG_ARM_ERRATA_430973
 	printk(KERN_INFO "RX-51: Enabling ARM errata 430973 workaround.\n");
 	/* set IBE to 1 */
 	rx51_secure_update_aux_cr(1 << 6, 0);
 #endif
+#endif
 
 	/* Ensure SDRC pins are mux'd for self-refresh */
 	omap_mux_init_signal("sdrc_cke0", OMAP_PIN_OUTPUT);


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