Mirrors/u-boot
2
0
Fork 0
mirror of https://github.com/AsahiLinux/u-boot synced 2024-11-25 22:20:45 +00:00
Code Issues Projects Releases Packages Wiki Activity

ARM1176: Coexist with other ARM1176 platforms

Browse source 
The current ARM1176 CPU specific code is too specific to the SMDK6400
architecture.  The following changes were necessary prerequisites for the
addition of other SoCs based on ARM1176.

Existing board's (SMDK6400) configuration has been modified to keep behavior
unchanged despite these changes.

1. Peripheral port remap configurability
The earlier code had hardcoded remap values specific to s3c64xx in start.S.
This change makes the peripheral port remap addresses and sizes configurable.

2. U-Boot code relocation support
Most architectures allow u-boot code to run initially at a different
address (possibly in NOR) and then get relocated to its final resting place
in RAM.  Added support for this capability in ARM1176 architecture.

3. Disable TCM if necessary
If a ROM based bootloader happened to have initialized TCM, we disable it here
to keep things sane.

4. Remove unnecessary SoC specific includes
ARM1176 code does not really need this SoC specific include.  The presence
of this include prevents builds on other ARM1176 archs.

5. Modified virt-to-phys conversion during MMU disable
The original MMU disable code masks out too many bits from the load address
when it tries to figure out the physical address of the jump target label.
Consequently, it ends up branching to the wrong address after disabling the
MMU.

Signed-off-by: Cyril Chemparathy <cyril@ti.com>
Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>
This commit is contained in:
Cyril Chemparathy 2010-06-07 14:13:27 -04:00 committed by Tom
parent b5d289fc29
commit 678e008c3a
3 changed files with 53 additions and 23 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
arch/arm/cpu/arm1176/cpu.c
View file

@ -33,9 +33,6 @@
#include <common.h>
#include <command.h>
#ifdef CONFIG_S3C64XX
#include <asm/arch/s3c6400.h>
#endif
#include <asm/system.h>
static void cache_flush (void);

65
arch/arm/cpu/arm1176/start.S
View file

@ -1,5 +1,5 @@
/*
* armboot - Startup Code for S3C6400/ARM1176 CPU-core
* armboot - Startup Code for ARM1176 CPU-core
*
* Copyright (c) 2007 Samsung Electronics
*
@ -35,9 +35,6 @@
#ifdef CONFIG_ENABLE_MMU
#include <asm/proc/domain.h>
#endif
#ifdef CONFIG_S3C64XX
#include <asm/arch/s3c6400.h>
#endif
#if !defined(CONFIG_ENABLE_MMU) && !defined(CONFIG_SYS_PHY_UBOOT_BASE)
#define CONFIG_SYS_PHY_UBOOT_BASE CONFIG_SYS_UBOOT_BASE
@ -172,14 +169,10 @@ cpu_init_crit:
bic r0, r0, #0x00000087 @ clear bits 7, 2:0 (B--- -CAM)
orr r0, r0, #0x00000002 @ set bit 2 (A) Align
orr r0, r0, #0x00001000 @ set bit 12 (I) I-Cache
/* Prepare to disable the MMU */
adr r1, mmu_disable_phys
/* We presume we're within the first 1024 bytes */
and r1, r1, #0x3fc
ldr r2, _TEXT_PHY_BASE
ldr r3, =0xfff00000
and r2, r2, r3
orr r2, r2, r1
adr r2, mmu_disable_phys
sub r2, r2, #(CONFIG_SYS_PHY_UBOOT_BASE - TEXT_BASE)
b mmu_disable
.align 5
@ -189,14 +182,30 @@ mmu_disable:
nop
nop
mov pc, r2
mmu_disable_phys:
#ifdef CONFIG_DISABLE_TCM
/*
* Disable the TCMs
*/
mrc p15, 0, r0, c0, c0, 2 /* Return TCM details */
cmp r0, #0
beq skip_tcmdisable
mov r1, #0
mov r2, #1
tst r0, r2
mcrne p15, 0, r1, c9, c1, 1 /* Disable Instruction TCM if present*/
tst r0, r2, LSL #16
mcrne p15, 0, r1, c9, c1, 0 /* Disable Data TCM if present*/
skip_tcmdisable:
#endif
#endif
mmu_disable_phys:
#ifdef CONFIG_S3C64XX
#ifdef CONFIG_PERIPORT_REMAP
/* Peri port setup */
ldr r0, =0x70000000
orr r0, r0, #0x13
mcr p15,0,r0,c15,c2,4 @ 256M (0x70000000 - 0x7fffffff)
ldr r0, =CONFIG_PERIPORT_BASE
orr r0, r0, #CONFIG_PERIPORT_SIZE
mcr p15,0,r0,c15,c2,4
#endif
/*
@ -204,7 +213,25 @@ mmu_disable_phys:
*/
bl lowlevel_init /* go setup pll,mux,memory */
after_copy:
#ifndef CONFIG_SKIP_RELOCATE_UBOOT
relocate: /* relocate U-Boot to RAM */
adr r0, _start /* r0 <- current position of code */
ldr r1, _TEXT_BASE /* test if we run from flash or RAM */
cmp r0, r1 /* don't reloc during debug */
beq stack_setup
ldr r2, _armboot_start
ldr r3, _bss_start
sub r2, r3, r2 /* r2 <- size of armboot */
add r2, r0, r2 /* r2 <- source end address */
copy_loop:
ldmia r0!, {r3-r10} /* copy from source address [r0] */
stmia r1!, {r3-r10} /* copy to target address [r1] */
cmp r0, r2 /* until source end addreee [r2] */
ble copy_loop
#endif /* CONFIG_SKIP_RELOCATE_UBOOT */
#ifdef CONFIG_ENABLE_MMU
enable_mmu:
/* enable domain access */
@ -240,9 +267,9 @@ mmu_enable:
nop
nop
mov pc, r2
skip_hw_init:
#endif
skip_hw_init:
/* Set up the stack */
stack_setup:
ldr r0, =CONFIG_SYS_UBOOT_BASE /* base of copy in DRAM */
@ -310,6 +337,8 @@ phy_last_jump:
mov r0, #0
mov pc, r9
#endif
/*
*************************************************************************
*

8
include/configs/smdk6400.h
View file

@ -40,6 +40,12 @@
#define CONFIG_S3C64XX 1 /* in a SAMSUNG S3C64XX Family */
#define CONFIG_SMDK6400 1 /* on a SAMSUNG SMDK6400 Board */
#define CONFIG_SKIP_RELOCATE_UBOOT
#define CONFIG_PERIPORT_REMAP
#define CONFIG_PERIPORT_BASE 0x70000000
#define CONFIG_PERIPORT_SIZE 0x13
#define CONFIG_SYS_SDRAM_BASE 0x50000000
/* input clock of PLL: SMDK6400 has 12MHz input clock */
@ -61,8 +67,6 @@
#define CONFIG_DISPLAY_CPUINFO
#define CONFIG_DISPLAY_BOARDINFO
#undef CONFIG_SKIP_RELOCATE_UBOOT
/*
* Size of malloc() pool
*/