u-boot/arch/arm/cpu/armv7/mx5/lowlevel_init.S
Fabio Estevam 41c881c0ca mx53: Turn off child clocks before reconfigure perclk_root
In addition to ensuring that PERCLK remains at least 2.5 times slower
than the AHB clock, certain steps need to be followed to ensure robust
operation of PERCLK when reconfiguring the PERCLK clock source.

To properly configure the PERCLK clock source, the following steps are
required:

1.In the CCGR registers, gate the clocks to all PERCLK-dependent
  modules.
2.Select the desired input clock for the PERCLK root clock (to be either
  source from the peripherals main source clock or the
  lp_apm clock source). Refer to the CMCBR register,  perclk_lp_apm_sel bit.
3.Configure the perclk_pred1, perclk_pred2, and perclk_podf dividers
  to the desired setting.  Refer to the CBCDR register for details.
4.In the CCGR registers, enable the desired clocks for the
  PERCLK-dependent module clocks.

If these steps aren't followed, GPT timer may stop and the kernel stops
at "Calibrating delay loop".

Signed-off-by: Terry Lv <r65388@freescale.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
2011-11-04 22:06:37 +01:00

351 lines
8 KiB
ArmAsm

/*
* Copyright (C) 2007, Guennadi Liakhovetski <lg@denx.de>
*
* (C) Copyright 2009 Freescale Semiconductor, Inc.
*
* 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 <config.h>
#include <asm/arch/imx-regs.h>
#include <generated/asm-offsets.h>
/*
* L2CC Cache setup/invalidation/disable
*/
.macro init_l2cc
/* explicitly disable L2 cache */
mrc 15, 0, r0, c1, c0, 1
bic r0, r0, #0x2
mcr 15, 0, r0, c1, c0, 1
/* reconfigure L2 cache aux control reg */
mov r0, #0xC0 /* tag RAM */
add r0, r0, #0x4 /* data RAM */
orr r0, r0, #(1 << 24) /* disable write allocate delay */
orr r0, r0, #(1 << 23) /* disable write allocate combine */
orr r0, r0, #(1 << 22) /* disable write allocate */
#if defined(CONFIG_MX51)
ldr r1, =0x0
ldr r3, [r1, #ROM_SI_REV]
cmp r3, #0x10
/* disable write combine for TO 2 and lower revs */
orrls r0, r0, #(1 << 25)
#endif
mcr 15, 1, r0, c9, c0, 2
.endm /* init_l2cc */
/* AIPS setup - Only setup MPROTx registers.
* The PACR default values are good.*/
.macro init_aips
/*
* Set all MPROTx to be non-bufferable, trusted for R/W,
* not forced to user-mode.
*/
ldr r0, =AIPS1_BASE_ADDR
ldr r1, =0x77777777
str r1, [r0, #0x0]
str r1, [r0, #0x4]
ldr r0, =AIPS2_BASE_ADDR
str r1, [r0, #0x0]
str r1, [r0, #0x4]
/*
* Clear the on and off peripheral modules Supervisor Protect bit
* for SDMA to access them. Did not change the AIPS control registers
* (offset 0x20) access type
*/
.endm /* init_aips */
/* M4IF setup */
.macro init_m4if
#ifdef CONFIG_MX51
/* VPU and IPU given higher priority (0x4)
* IPU accesses with ID=0x1 given highest priority (=0xA)
*/
ldr r0, =M4IF_BASE_ADDR
ldr r1, =0x00000203
str r1, [r0, #0x40]
ldr r1, =0x0
str r1, [r0, #0x44]
ldr r1, =0x00120125
str r1, [r0, #0x9C]
ldr r1, =0x001901A3
str r1, [r0, #0x48]
#endif
.endm /* init_m4if */
.macro setup_pll pll, freq
ldr r0, =\pll
ldr r1, =0x00001232
str r1, [r0, #PLL_DP_CTL] /* Set DPLL ON (set UPEN bit): BRMO=1 */
mov r1, #0x2
str r1, [r0, #PLL_DP_CONFIG] /* Enable auto-restart AREN bit */
ldr r1, W_DP_OP_\freq
str r1, [r0, #PLL_DP_OP]
str r1, [r0, #PLL_DP_HFS_OP]
ldr r1, W_DP_MFD_\freq
str r1, [r0, #PLL_DP_MFD]
str r1, [r0, #PLL_DP_HFS_MFD]
ldr r1, W_DP_MFN_\freq
str r1, [r0, #PLL_DP_MFN]
str r1, [r0, #PLL_DP_HFS_MFN]
ldr r1, =0x00001232
str r1, [r0, #PLL_DP_CTL]
1: ldr r1, [r0, #PLL_DP_CTL]
ands r1, r1, #0x1
beq 1b
.endm
.macro setup_pll_errata pll, freq
ldr r2, =\pll
mov r1, #0x0
str r1, [r2, #PLL_DP_CONFIG] /* Disable auto-restart AREN bit */
ldr r1, =0x00001236
str r1, [r2, #PLL_DP_CTL] /* Restart PLL with PLM=1 */
1: ldr r1, [r2, #PLL_DP_CTL] /* Wait for lock */
ands r1, r1, #0x1
beq 1b
ldr r5, \freq
str r5, [r2, #PLL_DP_MFN] /* Modify MFN value */
str r5, [r2, #PLL_DP_HFS_MFN]
mov r1, #0x1
str r1, [r2, #PLL_DP_CONFIG] /* Reload MFN value */
2: ldr r1, [r2, #PLL_DP_CONFIG]
tst r1, #1
bne 2b
ldr r1, =100 /* Wait at least 4 us */
3: subs r1, r1, #1
bge 3b
mov r1, #0x2
str r1, [r2, #PLL_DP_CONFIG] /* Enable auto-restart AREN bit */
.endm
.macro init_clock
ldr r0, =CCM_BASE_ADDR
#if defined(CONFIG_MX51)
/* Gate of clocks to the peripherals first */
ldr r1, =0x3FFFFFFF
str r1, [r0, #CLKCTL_CCGR0]
ldr r1, =0x0
str r1, [r0, #CLKCTL_CCGR1]
str r1, [r0, #CLKCTL_CCGR2]
str r1, [r0, #CLKCTL_CCGR3]
ldr r1, =0x00030000
str r1, [r0, #CLKCTL_CCGR4]
ldr r1, =0x00FFF030
str r1, [r0, #CLKCTL_CCGR5]
ldr r1, =0x00000300
str r1, [r0, #CLKCTL_CCGR6]
/* Disable IPU and HSC dividers */
mov r1, #0x60000
str r1, [r0, #CLKCTL_CCDR]
/* Make sure to switch the DDR away from PLL 1 */
ldr r1, =0x19239145
str r1, [r0, #CLKCTL_CBCDR]
/* make sure divider effective */
1: ldr r1, [r0, #CLKCTL_CDHIPR]
cmp r1, #0x0
bne 1b
#else
ldr r1, =0x3FFFFFFF
str r1, [r0, #CLKCTL_CCGR0]
ldr r1, =0x0
str r1, [r0, #CLKCTL_CCGR1]
str r1, [r0, #CLKCTL_CCGR2]
str r1, [r0, #CLKCTL_CCGR3]
str r1, [r0, #CLKCTL_CCGR7]
ldr r1, =0x00030000
str r1, [r0, #CLKCTL_CCGR4]
ldr r1, =0x00FFF030
str r1, [r0, #CLKCTL_CCGR5]
ldr r1, =0x0F00030F
str r1, [r0, #CLKCTL_CCGR6]
#endif
/* Switch ARM to step clock */
mov r1, #0x4
str r1, [r0, #CLKCTL_CCSR]
#if defined(CONFIG_MX51_PLL_ERRATA)
setup_pll PLL1_BASE_ADDR, 864
setup_pll_errata PLL1_BASE_ADDR, W_DP_MFN_800_DIT
#else
setup_pll PLL1_BASE_ADDR, 800
#endif
#if defined(CONFIG_MX51)
setup_pll PLL3_BASE_ADDR, 665
/* Switch peripheral to PLL 3 */
ldr r0, =CCM_BASE_ADDR
ldr r1, =0x000010C0
orr r1,r1,#CONFIG_SYS_DDR_CLKSEL
str r1, [r0, #CLKCTL_CBCMR]
ldr r1, =0x13239145
str r1, [r0, #CLKCTL_CBCDR]
setup_pll PLL2_BASE_ADDR, 665
/* Switch peripheral to PLL2 */
ldr r0, =CCM_BASE_ADDR
ldr r1, =0x19239145
str r1, [r0, #CLKCTL_CBCDR]
ldr r1, =0x000020C0
orr r1,r1,#CONFIG_SYS_DDR_CLKSEL
str r1, [r0, #CLKCTL_CBCMR]
#endif
setup_pll PLL3_BASE_ADDR, 216
/* Set the platform clock dividers */
ldr r0, =ARM_BASE_ADDR
ldr r1, =0x00000725
str r1, [r0, #0x14]
ldr r0, =CCM_BASE_ADDR
#if defined(CONFIG_MX51)
/* Run 3.0 at Full speed, for other TO's wait till we increase VDDGP */
ldr r1, =0x0
ldr r3, [r1, #ROM_SI_REV]
cmp r3, #0x10
movls r1, #0x1
movhi r1, #0
#else
mov r1, #0
#endif
str r1, [r0, #CLKCTL_CACRR]
/* Switch ARM back to PLL 1 */
mov r1, #0
str r1, [r0, #CLKCTL_CCSR]
#if defined(CONFIG_MX51)
/* setup the rest */
/* Use lp_apm (24MHz) source for perclk */
ldr r1, =0x000020C2
orr r1,r1,#CONFIG_SYS_DDR_CLKSEL
str r1, [r0, #CLKCTL_CBCMR]
/* ddr clock from PLL 1, all perclk dividers are 1 since using 24MHz */
ldr r1, =CONFIG_SYS_CLKTL_CBCDR
str r1, [r0, #CLKCTL_CBCDR]
#endif
/* Restore the default values in the Gate registers */
ldr r1, =0xFFFFFFFF
str r1, [r0, #CLKCTL_CCGR0]
str r1, [r0, #CLKCTL_CCGR1]
str r1, [r0, #CLKCTL_CCGR2]
str r1, [r0, #CLKCTL_CCGR3]
str r1, [r0, #CLKCTL_CCGR4]
str r1, [r0, #CLKCTL_CCGR5]
str r1, [r0, #CLKCTL_CCGR6]
#if defined(CONFIG_MX53)
str r1, [r0, #CLKCTL_CCGR7]
#endif
#if defined(CONFIG_MX51)
/* Use PLL 2 for UART's, get 66.5MHz from it */
ldr r1, =0xA5A2A020
str r1, [r0, #CLKCTL_CSCMR1]
ldr r1, =0x00C30321
str r1, [r0, #CLKCTL_CSCDR1]
#elif defined(CONFIG_MX53)
ldr r1, [r0, #CLKCTL_CSCDR1]
orr r1, r1, #0x3f
eor r1, r1, #0x3f
orr r1, r1, #0x21
str r1, [r0, #CLKCTL_CSCDR1]
#endif
/* make sure divider effective */
1: ldr r1, [r0, #CLKCTL_CDHIPR]
cmp r1, #0x0
bne 1b
mov r1, #0x0
str r1, [r0, #CLKCTL_CCDR]
/* for cko - for ARM div by 8 */
mov r1, #0x000A0000
add r1, r1, #0x00000F0
str r1, [r0, #CLKCTL_CCOSR]
.endm
.macro setup_wdog
ldr r0, =WDOG1_BASE_ADDR
mov r1, #0x30
strh r1, [r0]
.endm
.section ".text.init", "x"
.globl lowlevel_init
lowlevel_init:
#if defined(CONFIG_MX51)
ldr r0, =GPIO1_BASE_ADDR
ldr r1, [r0, #0x0]
orr r1, r1, #(1 << 23)
str r1, [r0, #0x0]
ldr r1, [r0, #0x4]
orr r1, r1, #(1 << 23)
str r1, [r0, #0x4]
#endif
init_l2cc
init_aips
init_m4if
init_clock
/* r12 saved upper lr*/
mov pc,lr
/* Board level setting value */
W_DP_OP_864: .word DP_OP_864
W_DP_MFD_864: .word DP_MFD_864
W_DP_MFN_864: .word DP_MFN_864
W_DP_MFN_800_DIT: .word DP_MFN_800_DIT
W_DP_OP_800: .word DP_OP_800
W_DP_MFD_800: .word DP_MFD_800
W_DP_MFN_800: .word DP_MFN_800
W_DP_OP_665: .word DP_OP_665
W_DP_MFD_665: .word DP_MFD_665
W_DP_MFN_665: .word DP_MFN_665
W_DP_OP_216: .word DP_OP_216
W_DP_MFD_216: .word DP_MFD_216
W_DP_MFN_216: .word DP_MFN_216