For early boot logs, did you enabled required configs???? Regards, Jagan.
On Mon, Oct 31, 2011 at 8:43 PM, Sam King <[email protected]> wrote: > Hello, > > I am having trouble getting information out of my tegra2 (ventana) > system early in the boot sequence, which is making debugging some > early boot code I am working on nearly impossible. My code runs right > after the bootloader well before the MMU has been enabled. I tried > writing pixel valued directly to both of the video memory regions for > my platform, but nothing happend. Since fastboot prints some simple > messages to the screen I am assuming this is possible, I just can't > figure out how. > > I also tried enabling the early boot 8250 driver and I tried writing > directly to the serial port myself using this code, any help is > appreciated: > > #define FCR (2<<2) > #define IER (1<<2) > #define DLL 0 > #define DLH (1<<2) > #define LCR (3<<2) > #define MCR (4<<2) > #define TX 0 > #define LCR_DLAB 0x80 > > .global _reset > _reset: > /* physical serial port location, uses 8250 interface on > ventana board */ > ldr r0, =0x70006300 > /* 8n1 */ > mov r1, #0x3 > strb r1, [r0, #LCR] > /* interrupts off */ > mov r1, #0 > strb r1, [r0, #IER] > /* no fifo */ > mov r1, #0 > strb r1, [r0, #FCR] > > /* 115200 baud rate, usbclk is 216000000 for ventana divisor > = 0x75 */ > ldrb r1, [r0, #LCR] > orr r1, r1, #LCR_DLAB > strb r1, [r0, #LCR] > mov r1, #0x75 > strb r1, [r0, #DLL] > mov r1, #0x0 > strb r1, [r0, #DLH] > mov r1, #3 > strb r1, [r0, #LCR] > > /* Send an 'A' */ > mov r1, #0x41 > strb r1, [r0, #TX] > > -- > unsubscribe: [email protected] > website: http://groups.google.com/group/android-kernel -- unsubscribe: [email protected] website: http://groups.google.com/group/android-kernel
