u-boot/board/freescale/common/ngpixis.c
Timur Tabi 5a46960883 p2020ds: add alternate boot bank support using the ngPIXIS FPGA
The Freescale P2020DS board uses a new type of PIXIS FPGA, called the ngPIXIS.
The ngPIXIS has one distinct new feature: the values of the on-board switches
can be selectively overridden with shadow registers.  This feature is used to
boot from a different NOR flash bank, instead of having a register dedicated
for this purpose.  Because the ngPIXIS is so different from the previous PIXIS,
a new file is introduced: ngpixis.c.

Also update the P2020DS checkboard() function to use the new macros defined
in the header file.

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2010-04-07 00:21:28 -05:00

136 lines
3.5 KiB
C

/**
* Copyright 2010 Freescale Semiconductor
* Author: Timur Tabi <timur@freescale.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This file provides support for the ngPIXIS, a board-specific FPGA used on
* some Freescale reference boards.
*
* A "switch" is black rectangular block on the motherboard. It contains
* eight "bits". The ngPIXIS has a set of memory-mapped registers (SWx) that
* shadow the actual physical switches. There is also another set of
* registers (ENx) that tell the ngPIXIS which bits of SWx should actually be
* used to override the values of the bits in the physical switches.
*
* The following macros need to be defined:
*
* PIXIS_BASE - The virtual address of the base of the PIXIS register map
*
* PIXIS_LBMAP_SWITCH - The switch number (i.e. the "x" in "SWx"). This value
* is used in the PIXIS_SW() macro to determine which offset in
* the PIXIS register map corresponds to the physical switch that controls
* the boot bank.
*
* PIXIS_LBMAP_MASK - A bit mask the defines which bits in SWx to use.
*
* PIXIS_LBMAP_SHIFT - The shift value that corresponds to PIXIS_LBMAP_MASK.
*
* PIXIS_LBMAP_ALTBANK - The value to program into SWx to tell the ngPIXIS to
* boot from the alternate bank.
*/
#include <common.h>
#include <command.h>
#include <watchdog.h>
#include <asm/cache.h>
#include <asm/io.h>
#include "ngpixis.h"
/*
* Reset the board. This ignores the ENx registers.
*/
void pixis_reset(void)
{
out_8(&pixis->rst, 0);
while (1);
}
/*
* Reset the board. Like pixis_reset(), but it honors the ENx registers.
*/
void pixis_bank_reset(void)
{
out_8(&pixis->vctl, 0);
out_8(&pixis->vctl, 1);
while (1);
}
/**
* Set the boot bank to the power-on default bank
*/
void clear_altbank(void)
{
/* Tell the ngPIXIS to use this the bits in the physical switch for the
* boot bank value, instead of the SWx register. We need to be careful
* only to set the bits in SWx that correspond to the boot bank.
*/
clrbits_8(&PIXIS_EN(PIXIS_LBMAP_SWITCH), PIXIS_LBMAP_MASK);
}
/**
* Set the boot bank to the alternate bank
*/
void set_altbank(void)
{
/* Program the alternate bank number into the SWx register.
*/
clrsetbits_8(&PIXIS_SW(PIXIS_LBMAP_SWITCH), PIXIS_LBMAP_MASK,
PIXIS_LBMAP_ALTBANK);
/* Tell the ngPIXIS to use this the bits in the SWx register for the
* boot bank value, instead of the physical switch. We need to be
* careful only to set the bits in SWx that correspond to the boot bank.
*/
setbits_8(&PIXIS_EN(PIXIS_LBMAP_SWITCH), PIXIS_LBMAP_MASK);
}
int pixis_reset_cmd(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
unsigned int i;
char *p_altbank = NULL;
char *unknown_param = NULL;
/* No args is a simple reset request.
*/
if (argc <= 1)
pixis_reset();
for (i = 1; i < argc; i++) {
if (strcmp(argv[i], "altbank") == 0) {
p_altbank = argv[i];
continue;
}
unknown_param = argv[i];
}
if (unknown_param) {
printf("Invalid option: %s\n", unknown_param);
return 1;
}
if (p_altbank)
set_altbank();
else
clear_altbank();
pixis_bank_reset();
/* Shouldn't be reached. */
return 0;
}
U_BOOT_CMD(
pixis_reset, CONFIG_SYS_MAXARGS, 1, pixis_reset_cmd,
"Reset the board using the FPGA sequencer",
"- hard reset to default bank\n"
"pixis_reset altbank - reset to alternate bank\n"
);