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 --- v6: remove CONFIG_SKIP_LOWLEVEL_INIT support v6: modified virt-to-phys mapping to use offset instead of mask v6: changed code comments v6: removed undef CONFIG_SKIP_RELOCATE_UBOOT from smdk6400 config v5: rebased on master in u-boot-arm.git v4: rebased on next in u-boot-arm.git v3: unchanged from v2 v2: unchanged from v1
arch/arm/cpu/arm1176/cpu.c | 3 -- arch/arm/cpu/arm1176/start.S | 65 ++++++++++++++++++++++++++++++----------- include/configs/smdk6400.h | 8 ++++- 3 files changed, 53 insertions(+), 23 deletions(-)
diff --git a/arch/arm/cpu/arm1176/cpu.c b/arch/arm/cpu/arm1176/cpu.c index befa0cd..c0fd114 100644 --- a/arch/arm/cpu/arm1176/cpu.c +++ b/arch/arm/cpu/arm1176/cpu.c @@ -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); diff --git a/arch/arm/cpu/arm1176/start.S b/arch/arm/cpu/arm1176/start.S index e2b6c9b..a540edb 100644 --- a/arch/arm/cpu/arm1176/start.S +++ b/arch/arm/cpu/arm1176/start.S @@ -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 + + /* ************************************************************************* * diff --git a/include/configs/smdk6400.h b/include/configs/smdk6400.h index f04feae..624fe04 100644 --- a/include/configs/smdk6400.h +++ b/include/configs/smdk6400.h @@ -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 */