view target-utils/include/romvars.h @ 407:19e5a3e2f9c0

fcup-settime: moved time() retrieval a little closer to the output A fundamental problem with all simple time transfer tools is that there is always some delay between the time retrieval on the source system and that transmitted time being set on the destination, and the resulting time on the destination system is off by that delay amount. This delay cannot be fully eliminated when working in a simple environment like ours, but we should make our best effort to minimize it. In the present case, moving the atinterf_init() call before the time() retrieval should make a teensy-tiny improvement.
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 11 Aug 2018 21:52:17 +0000
parents e7502631a0f9
children
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/*
 * Our loadagent will always be loaded into Calypso targets by the on-chip
 * boot ROM operating in the UART download mode.  The lowest IRAM address
 * at which we can load our code is 0x800750; somewhat lower at 0x800518
 * the boot ROM downloader has a few variables which may have been intended
 * to be private to the boot ROM, but which are useful to us.  For example,
 * by looking at these variables, we can see which of the two UARTs was
 * used to feed our code to the boot ROM, and use the same UART for
 * subsequent communication - without building multiple versions of our
 * loadagent or resorting to other ugliness.
 *
 * This header file defines the layout of the IRAM structure in question,
 * based on the disassembly of the boot ROM.
 */

#ifndef __ROMVARS_H
#define	__ROMVARS_H

#include "types.h"

struct boot_rom_vars {
	u8	baud_rate_code;
	u8	pad1[3];
	u32	uart_timeout;
	u8	uart_id;
	u8	pll_config;
	u16	cs_ws_config;
	u8	clktcxo_13mhz;
	u8	rhea_cntl;
	u16	chksum_cmd;
	u16	chksum_accum;
	u16	pad2;
	u32	branch_addr;
};

#endif	/* include guard */