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/*-
* Copyright (c) 2006 M. Warner Losh. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* This software is derived from software provide by Kwikbyte who specifically
* disclaimed copyright on the code.
*
* $FreeBSD$
*/
#include "at91rm9200.h"
#include "at91rm9200_lowlevel.h"
extern int __bss_start__[];
extern int __bss_end__[];
#define BAUD 115200
#define AT91C_US_ASYNC_MODE (AT91C_US_USMODE_NORMAL | AT91C_US_NBSTOP_1_BIT | \
AT91C_US_PAR_NONE | AT91C_US_CHRL_8_BITS | AT91C_US_CLKS_CLOCK)
/*
* void DefaultSystemInit(void)
* Load the system with sane values based on how the system is configured.
* at91rm9200_lowlevel.h is expected to define the necessary parameters.
*/
void
_init(void)
{
int *i;
AT91PS_USART pUSART = (AT91PS_USART)AT91C_BASE_DBGU;
AT91PS_PDC pPDC = (AT91PS_PDC)&(pUSART->US_RPR);
register unsigned value;
volatile sdram_size_t *p = (sdram_size_t *)SDRAM_BASE;
#ifdef BOOT_TSC
// For the TSC board, we turn ON the one LED we have while
// early in boot.
AT91C_BASE_PIOC->PIO_PER = AT91C_PIO_PC10;
AT91C_BASE_PIOC->PIO_OER = AT91C_PIO_PC10;
AT91C_BASE_PIOC->PIO_CODR = AT91C_PIO_PC10;
#endif
#ifdef BOOT_KB920X
AT91C_BASE_PIOC->PIO_PER = AT91C_PIO_PC18 | AT91C_PIO_PC19 |
AT91C_PIO_PC20;
AT91C_BASE_PIOC->PIO_OER = AT91C_PIO_PC18 | AT91C_PIO_PC19 |
AT91C_PIO_PC20;
AT91C_BASE_PIOC->PIO_SODR = AT91C_PIO_PC18 | AT91C_PIO_PC19 |
AT91C_PIO_PC20;
AT91C_BASE_PIOC->PIO_CODR = AT91C_PIO_PC18;
#endif
// configure clocks
// assume:
// main osc = 10Mhz
// PLLB configured for 96MHz (48MHz after div)
// CSS = PLLB
// set PLLA = 180MHz
// assume main osc = 10Mhz
// div = 5 , out = 2 (150MHz = 240MHz)
value = AT91C_BASE_CKGR->CKGR_PLLAR;
value &= ~(AT91C_CKGR_DIVA | AT91C_CKGR_OUTA | AT91C_CKGR_MULA);
value |= OSC_MAIN_FREQ_DIV | AT91C_CKGR_OUTA_2 | AT91C_CKGR_SRCA |
((OSC_MAIN_MULT - 1) << 16);
AT91C_BASE_CKGR->CKGR_PLLAR = value;
// wait for lock
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_LOCKA))
continue;
// change divider = 3, pres = 1
value = AT91C_BASE_PMC->PMC_MCKR;
value &= ~(AT91C_PMC_MDIV | AT91C_PMC_PRES);
value |= AT91C_PMC_MDIV_3 | AT91C_PMC_PRES_CLK;
AT91C_BASE_PMC->PMC_MCKR = value;
// wait for update
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY))
continue;
// change CSS = PLLA
value &= ~AT91C_PMC_CSS;
value |= AT91C_PMC_CSS_PLLA_CLK;
AT91C_BASE_PMC->PMC_MCKR = value;
// wait for update
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY))
continue;
#ifdef BOOT_KB920X
// setup flash access (allow ample margin)
// 9 wait states, 1 setup, 1 hold, 1 float for 8-bit device
((AT91PS_SMC2)AT91C_BASE_SMC2)->SMC2_CSR[0] =
AT91C_SMC2_WSEN |
(9 & AT91C_SMC2_NWS) |
((1 << 8) & AT91C_SMC2_TDF) |
AT91C_SMC2_DBW_8 |
((1 << 24) & AT91C_SMC2_RWSETUP) |
((1 << 29) & AT91C_SMC2_RWHOLD);
#endif
// setup SDRAM access
// EBI chip-select register (CS1 = SDRAM controller)
// 9 col, 13row, 4 bank, CAS2
// write recovery = 2 (Twr)
// row cycle = 5 (Trc)
// precharge delay = 2 (Trp)
// row to col delay 2 (Trcd)
// active to precharge = 4 (Tras)
// exit self refresh to active = 6 (Txsr)
value = ((AT91PS_EBI)AT91C_BASE_EBI)->EBI_CSA;
value &= ~AT91C_EBI_CS1A;
value |= AT91C_EBI_CS1A_SDRAMC;
AT91C_BASE_EBI->EBI_CSA = value;
AT91C_BASE_SDRC->SDRC_CR =
AT91C_SDRC_NC_9 |
AT91C_SDRC_NR_13 |
AT91C_SDRC_NB_4_BANKS |
AT91C_SDRC_CAS_2 |
((2 << 7) & AT91C_SDRC_TWR) |
((5 << 11) & AT91C_SDRC_TRC) |
((2 << 15) & AT91C_SDRC_TRP) |
((2 << 19) & AT91C_SDRC_TRCD) |
((4 << 23) & AT91C_SDRC_TRAS) |
((6 << 27) & AT91C_SDRC_TXSR);
// Step 1: We assume 200us of idle time.
// Step 2: Issue an all banks precharge command
AT91C_BASE_SDRC->SDRC_MR = SDRAM_WIDTH | AT91C_SDRC_MODE_PRCGALL_CMD;
*p = 0;
// Step 3: Issue 8 Auto-refresh (CBR) cycles
AT91C_BASE_SDRC->SDRC_MR = SDRAM_WIDTH | AT91C_SDRC_MODE_RFSH_CMD;
*p = 0;
*p = 0;
*p = 0;
*p = 0;
*p = 0;
*p = 0;
*p = 0;
*p = 0;
// Step 4: Issue an Mode Set Register (MRS) cycle to program in
// the parameters that we setup in the SDRC_CR register above.
AT91C_BASE_SDRC->SDRC_MR = SDRAM_WIDTH | AT91C_SDRC_MODE_LMR_CMD;
*p = 0;
// Step 5: set the refresh timer and access memory to start it
// running. We have to wait 3 clocks after the LMR_CMD above,
// and this fits the bill nicely.
AT91C_BASE_SDRC->SDRC_TR = 7 * AT91C_MASTER_CLOCK / 1000000;
*p = 0;
// Step 6: Set normal mode.
AT91C_BASE_SDRC->SDRC_MR = SDRAM_WIDTH | AT91C_SDRC_MODE_NORMAL_CMD;
*p = 0;
#if SDRAM_WIDTH == AT91C_SDRC_DBW_32_BITS
// Turn on the upper 16 bits on the SDRAM bus.
AT91C_BASE_PIOC->PIO_ASR = 0xffff0000;
AT91C_BASE_PIOC->PIO_PDR = 0xffff0000;
#endif
// Configure DBGU -use local routine optimized for space
AT91C_BASE_PIOA->PIO_ASR = AT91C_PA31_DTXD | AT91C_PA30_DRXD;
AT91C_BASE_PIOA->PIO_PDR = AT91C_PA31_DTXD | AT91C_PA30_DRXD;
pUSART->US_IDR = (unsigned int) -1;
pUSART->US_CR =
AT91C_US_RSTRX | AT91C_US_RSTTX | AT91C_US_RXDIS | AT91C_US_TXDIS;
pUSART->US_BRGR = ((((AT91C_MASTER_CLOCK*10)/(BAUD*16))+5)/10);
pUSART->US_TTGR = 0;
pPDC->PDC_PTCR = AT91C_PDC_RXTDIS;
pPDC->PDC_PTCR = AT91C_PDC_TXTDIS;
pPDC->PDC_TNPR = 0;
pPDC->PDC_TNCR = 0;
pPDC->PDC_RNPR = 0;
pPDC->PDC_RNCR = 0;
pPDC->PDC_TPR = 0;
pPDC->PDC_TCR = 0;
pPDC->PDC_RPR = 0;
pPDC->PDC_RCR = 0;
pPDC->PDC_PTCR = AT91C_PDC_RXTEN;
pPDC->PDC_PTCR = AT91C_PDC_TXTEN;
pUSART->US_MR = AT91C_US_ASYNC_MODE;
pUSART->US_CR = AT91C_US_TXEN;
pUSART->US_CR = AT91C_US_RXEN;
/* Zero BSS now that we have memory setup */
i = (int *)__bss_start__;
while (i < (int *)__bss_end__)
*i++ = 0;
}
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