mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-16 17:58:23 +00:00
a21d0c2cc9
Add serial boot support Signed-off-by: TsiChung Liew <Tsi-Chung.Liew@freescale.com>
140 lines
3.5 KiB
C
140 lines
3.5 KiB
C
/*
|
|
*
|
|
* Copyright (C) 2004-2007 Freescale Semiconductor, Inc.
|
|
* TsiChung Liew (Tsi-Chung.Liew@freescale.com)
|
|
*
|
|
* See file CREDITS for list of people who contributed to this
|
|
* project.
|
|
*
|
|
* 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 program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
|
|
* MA 02111-1307 USA
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <asm/processor.h>
|
|
|
|
#include <asm/immap.h>
|
|
|
|
DECLARE_GLOBAL_DATA_PTR;
|
|
|
|
/*
|
|
* Low Power Divider specifications
|
|
*/
|
|
#define CLOCK_LPD_MIN (1 << 0) /* Divider (decoded) */
|
|
#define CLOCK_LPD_MAX (1 << 15) /* Divider (decoded) */
|
|
|
|
#define CLOCK_PLL_FVCO_MAX 540000000
|
|
#define CLOCK_PLL_FVCO_MIN 300000000
|
|
|
|
#define CLOCK_PLL_FSYS_MAX 266666666
|
|
#define CLOCK_PLL_FSYS_MIN 100000000
|
|
#define MHZ 1000000
|
|
|
|
void clock_enter_limp(int lpdiv)
|
|
{
|
|
volatile ccm_t *ccm = (volatile ccm_t *)MMAP_CCM;
|
|
int i, j;
|
|
|
|
/* Check bounds of divider */
|
|
if (lpdiv < CLOCK_LPD_MIN)
|
|
lpdiv = CLOCK_LPD_MIN;
|
|
if (lpdiv > CLOCK_LPD_MAX)
|
|
lpdiv = CLOCK_LPD_MAX;
|
|
|
|
/* Round divider down to nearest power of two */
|
|
for (i = 0, j = lpdiv; j != 1; j >>= 1, i++) ;
|
|
|
|
/* Apply the divider to the system clock */
|
|
ccm->cdr = (ccm->cdr & 0xF0FF) | CCM_CDR_LPDIV(i);
|
|
|
|
/* Enable Limp Mode */
|
|
ccm->misccr |= CCM_MISCCR_LIMP;
|
|
}
|
|
|
|
/*
|
|
* brief Exit Limp mode
|
|
* warning The PLL should be set and locked prior to exiting Limp mode
|
|
*/
|
|
void clock_exit_limp(void)
|
|
{
|
|
volatile ccm_t *ccm = (volatile ccm_t *)MMAP_CCM;
|
|
volatile pll_t *pll = (volatile pll_t *)MMAP_PLL;
|
|
|
|
/* Exit Limp mode */
|
|
ccm->misccr &= ~CCM_MISCCR_LIMP;
|
|
|
|
/* Wait for the PLL to lock */
|
|
while (!(pll->psr & PLL_PSR_LOCK)) ;
|
|
}
|
|
|
|
/*
|
|
* get_clocks() fills in gd->cpu_clock and gd->bus_clk
|
|
*/
|
|
int get_clocks(void)
|
|
{
|
|
|
|
volatile ccm_t *ccm = (volatile ccm_t *)MMAP_CCM;
|
|
volatile pll_t *pll = (volatile pll_t *)MMAP_PLL;
|
|
int vco, temp, pcrvalue, pfdr;
|
|
u8 bootmode;
|
|
|
|
pcrvalue = pll->pcr & 0xFF0F0FFF;
|
|
pfdr = pcrvalue >> 24;
|
|
|
|
if (pfdr == 0x1E)
|
|
bootmode = 0; /* Normal Mode */
|
|
|
|
#ifdef CONFIG_CF_SBF
|
|
bootmode = 3; /* Serial Mode */
|
|
#endif
|
|
|
|
if (bootmode == 0) {
|
|
/* Normal mode */
|
|
vco = ((pll->pcr & 0xFF000000) >> 24) * CONFIG_SYS_INPUT_CLKSRC;
|
|
if ((vco < CLOCK_PLL_FVCO_MIN) || (vco > CLOCK_PLL_FVCO_MAX)) {
|
|
/* Default value */
|
|
pcrvalue = (pll->pcr & 0x00FFFFFF);
|
|
pcrvalue |= 0x1E << 24;
|
|
pll->pcr = pcrvalue;
|
|
vco =
|
|
((pll->pcr & 0xFF000000) >> 24) *
|
|
CONFIG_SYS_INPUT_CLKSRC;
|
|
}
|
|
gd->vco_clk = vco; /* Vco clock */
|
|
} else if (bootmode == 3) {
|
|
/* serial mode */
|
|
vco = ((pll->pcr & 0xFF000000) >> 24) * CONFIG_SYS_INPUT_CLKSRC;
|
|
gd->vco_clk = vco; /* Vco clock */
|
|
}
|
|
|
|
if ((ccm->ccr & CCM_MISCCR_LIMP) == CCM_MISCCR_LIMP) {
|
|
/* Limp mode */
|
|
} else {
|
|
gd->inp_clk = CONFIG_SYS_INPUT_CLKSRC; /* Input clock */
|
|
|
|
temp = (pll->pcr & PLL_PCR_OUTDIV1_MASK) + 1;
|
|
gd->cpu_clk = vco / temp; /* cpu clock */
|
|
|
|
temp = ((pll->pcr & PLL_PCR_OUTDIV2_MASK) >> 4) + 1;
|
|
gd->flb_clk = vco / temp; /* flexbus clock */
|
|
gd->bus_clk = gd->flb_clk;
|
|
}
|
|
|
|
#ifdef CONFIG_FSL_I2C
|
|
gd->i2c1_clk = gd->bus_clk;
|
|
#endif
|
|
|
|
return (0);
|
|
}
|