diff options
| -rw-r--r-- | arch/arm/cpu/pxa/start.S | 112 | ||||
| -rw-r--r-- | arch/arm/cpu/pxa/u-boot.lds | 6 |
2 files changed, 116 insertions, 2 deletions
diff --git a/arch/arm/cpu/pxa/start.S b/arch/arm/cpu/pxa/start.S index 88a4cc2..6504819 100644 --- a/arch/arm/cpu/pxa/start.S +++ b/arch/arm/cpu/pxa/start.S @@ -38,6 +38,13 @@ #include <asm-offsets.h> #include <config.h> #include <version.h> + +#ifdef CONFIG_PXA25X +#if ((CONFIG_SYS_INIT_SP_ADDR) != 0xfffff800) +#error "Init SP address must be set to 0xfffff800 for PXA250" +#endif +#endif + .globl _start _start: b reset #ifdef CONFIG_SPL_BUILD @@ -153,6 +160,10 @@ reset: bl cpu_init_crit #endif +#ifdef CONFIG_PXA250 + bl lock_cache_for_stack +#endif + /* Set stackpointer in internal RAM to call board_init_f */ call_board_init_f: ldr sp, =(CONFIG_SYS_INIT_SP_ADDR) @@ -179,6 +190,11 @@ relocate_code: stack_setup: mov sp, r4 +/* Disable the Dcache RAM lock for stack now */ +#ifdef CONFIG_PXA250 + bl cpu_init_crit +#endif + adr r0, _start cmp r0, r6 beq clear_bss /* skip relocation */ @@ -291,7 +307,7 @@ _dynsym_start_ofs: * ************************************************************************* */ -#ifndef CONFIG_SKIP_LOWLEVEL_INIT +#if !defined(CONFIG_SKIP_LOWLEVEL_INIT) || defined(CONFIG_PXA250) cpu_init_crit: /* * flush v4 I/D caches @@ -311,7 +327,7 @@ cpu_init_crit: mcr p15, 0, r0, c1, c0, 0 mov pc, lr /* back to my caller */ -#endif /* CONFIG_SKIP_LOWLEVEL_INIT */ +#endif /* !CONFIG_SKIP_LOWLEVEL_INIT || CONFIG_PXA250 */ #ifndef CONFIG_SPL_BUILD /* @@ -495,3 +511,95 @@ fiq: #endif .align 5 #endif /* CONFIG_SPL_BUILD */ + + +/* + * Enable MMU to use DCache as DRAM. + * + * This is useful on PXA25x and PXA26x in early bootstages, where there is no + * other possible memory available to hold stack. + */ +#ifdef CONFIG_PXA250 +.macro CPWAIT reg + mrc p15, 0, \reg, c2, c0, 0 + mov \reg, \reg + sub pc, pc, #4 +.endm +lock_cache_for_stack: + /* Domain access -- enable for all CPs */ + ldr r0, =0x0000ffff + mcr p15, 0, r0, c3, c0, 0 + + /* Point TTBR to MMU table */ + ldr r0, =mmutable + mcr p15, 0, r0, c2, c0, 0 + + /* Kick in MMU, ICache, DCache, BTB */ + mrc p15, 0, r0, c1, c0, 0 + bic r0, #0x1b00 + bic r0, #0x0087 + orr r0, #0x1800 + orr r0, #0x0005 + mcr p15, 0, r0, c1, c0, 0 + CPWAIT r0 + + /* Unlock Icache, Dcache */ + mcr p15, 0, r0, c9, c1, 1 + mcr p15, 0, r0, c9, c2, 1 + + /* Flush Icache, Dcache, BTB */ + mcr p15, 0, r0, c7, c7, 0 + + /* Unlock I-TLB, D-TLB */ + mcr p15, 0, r0, c10, c4, 1 + mcr p15, 0, r0, c10, c8, 1 + + /* Flush TLB */ + mcr p15, 0, r0, c8, c7, 0 + + /* Allocate 4096 bytes of Dcache as RAM */ + + /* Drain pending loads and stores */ + mcr p15, 0, r0, c7, c10, 4 + + mov r4, #0x00 + mov r5, #0x00 + mov r2, #0x01 + mcr p15, 0, r0, c9, c2, 0 + CPWAIT r0 + + /* 128 lines reserved (128 x 32bytes = 4096 bytes total) */ + mov r0, #128 + ldr r1, =0xfffff000 + +alloc: + mcr p15, 0, r1, c7, c2, 5 + /* Drain pending loads and stores */ + mcr p15, 0, r0, c7, c10, 4 + strd r4, [r1], #8 + strd r4, [r1], #8 + strd r4, [r1], #8 + strd r4, [r1], #8 + subs r0, #0x01 + bne alloc + /* Drain pending loads and stores */ + mcr p15, 0, r0, c7, c10, 4 + mov r2, #0x00 + mcr p15, 0, r2, c9, c2, 0 + CPWAIT r0 + + mov pc, lr + +.section .mmutable, "a" +mmutable: + .align 14 + /* 0x00000000 - 0xffe00000 : 1:1, uncached mapping */ + .set __base, 0 + .rept 0xfff + .word (__base << 20) | 0xc12 + .set __base, __base + 1 + .endr + + /* 0xfff00000 : 1:1, cached mapping */ + .word (0xfff << 20) | 0x1c1e +#endif /* CONFIG_PXA250 */ diff --git a/arch/arm/cpu/pxa/u-boot.lds b/arch/arm/cpu/pxa/u-boot.lds index e163369..e86e781 100644 --- a/arch/arm/cpu/pxa/u-boot.lds +++ b/arch/arm/cpu/pxa/u-boot.lds @@ -63,6 +63,12 @@ SECTIONS *(.dynsym) } + . = ALIGN(4096); + + .mmutable : { + *(.mmutable) + } + _end = .; .bss __rel_dyn_start (OVERLAY) : { |