diff options
Diffstat (limited to 'arch/sh/boot/compressed/head_64.S')
| -rw-r--r-- | arch/sh/boot/compressed/head_64.S | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/arch/sh/boot/compressed/head_64.S b/arch/sh/boot/compressed/head_64.S new file mode 100644 index 000000000..9993113c6 --- /dev/null +++ b/arch/sh/boot/compressed/head_64.S @@ -0,0 +1,159 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * arch/shmedia/boot/compressed/head.S + * + * Copied from + * arch/shmedia/kernel/head.S + * which carried the copyright: + * Copyright (C) 2000, 2001 Paolo Alberelli + * + * Modification for compressed loader: + * Copyright (C) 2002 Stuart Menefy (stuart.menefy@st.com) + */ +#include <asm/cache.h> +#include <asm/tlb.h> +#include <cpu/mmu_context.h> +#include <cpu/registers.h> + +/* + * Fixed TLB entries to identity map the beginning of RAM + */ +#define MMUIR_TEXT_H 0x0000000000000003 | CONFIG_MEMORY_START + /* Enabled, Shared, ASID 0, Eff. Add. 0xA0000000 */ +#define MMUIR_TEXT_L 0x000000000000009a | CONFIG_MEMORY_START + /* 512 Mb, Cacheable (Write-back), execute, Not User, Ph. Add. */ + +#define MMUDR_CACHED_H 0x0000000000000003 | CONFIG_MEMORY_START + /* Enabled, Shared, ASID 0, Eff. Add. 0xA0000000 */ +#define MMUDR_CACHED_L 0x000000000000015a | CONFIG_MEMORY_START + /* 512 Mb, Cacheable (Write-back), read/write, Not User, Ph. Add. */ + +#define ICCR0_INIT_VAL ICCR0_ON | ICCR0_ICI /* ICE + ICI */ +#define ICCR1_INIT_VAL ICCR1_NOLOCK /* No locking */ + +#define OCCR0_INIT_VAL OCCR0_ON | OCCR0_OCI | OCCR0_WB /* OCE + OCI + WB */ +#define OCCR1_INIT_VAL OCCR1_NOLOCK /* No locking */ + + .text + + .global startup +startup: + /* + * Prevent speculative fetch on device memory due to + * uninitialized target registers. + * This must be executed before the first branch. + */ + ptabs/u r63, tr0 + ptabs/u r63, tr1 + ptabs/u r63, tr2 + ptabs/u r63, tr3 + ptabs/u r63, tr4 + ptabs/u r63, tr5 + ptabs/u r63, tr6 + ptabs/u r63, tr7 + synci + + /* + * Set initial TLB entries for cached and uncached regions. + * Note: PTA/BLINK is PIC code, PTABS/BLINK isn't ! + */ + /* Clear ITLBs */ + pta 1f, tr1 + movi ITLB_FIXED, r21 + movi ITLB_LAST_VAR_UNRESTRICTED+TLB_STEP, r22 +1: putcfg r21, 0, r63 /* Clear MMUIR[n].PTEH.V */ + addi r21, TLB_STEP, r21 + bne r21, r22, tr1 + + /* Clear DTLBs */ + pta 1f, tr1 + movi DTLB_FIXED, r21 + movi DTLB_LAST_VAR_UNRESTRICTED+TLB_STEP, r22 +1: putcfg r21, 0, r63 /* Clear MMUDR[n].PTEH.V */ + addi r21, TLB_STEP, r21 + bne r21, r22, tr1 + + /* Map one big (512Mb) page for ITLB */ + movi ITLB_FIXED, r21 + movi MMUIR_TEXT_L, r22 /* PTEL first */ + putcfg r21, 1, r22 /* Set MMUIR[0].PTEL */ + movi MMUIR_TEXT_H, r22 /* PTEH last */ + putcfg r21, 0, r22 /* Set MMUIR[0].PTEH */ + + /* Map one big CACHED (512Mb) page for DTLB */ + movi DTLB_FIXED, r21 + movi MMUDR_CACHED_L, r22 /* PTEL first */ + putcfg r21, 1, r22 /* Set MMUDR[0].PTEL */ + movi MMUDR_CACHED_H, r22 /* PTEH last */ + putcfg r21, 0, r22 /* Set MMUDR[0].PTEH */ + + /* ICache */ + movi ICCR_BASE, r21 + movi ICCR0_INIT_VAL, r22 + movi ICCR1_INIT_VAL, r23 + putcfg r21, ICCR_REG0, r22 + putcfg r21, ICCR_REG1, r23 + synci + + /* OCache */ + movi OCCR_BASE, r21 + movi OCCR0_INIT_VAL, r22 + movi OCCR1_INIT_VAL, r23 + putcfg r21, OCCR_REG0, r22 + putcfg r21, OCCR_REG1, r23 + synco + + /* + * Enable the MMU. + * From here-on code can be non-PIC. + */ + movi SR_HARMLESS | SR_ENABLE_MMU, r22 + putcon r22, SSR + movi 1f, r22 + putcon r22, SPC + synco + rte /* And now go into the hyperspace ... */ +1: /* ... that's the next instruction ! */ + + /* Set initial stack pointer */ + movi datalabel stack_start, r0 + ld.l r0, 0, r15 + + /* + * Clear bss + */ + pt 1f, tr1 + movi datalabel __bss_start, r22 + movi datalabel _end, r23 +1: st.l r22, 0, r63 + addi r22, 4, r22 + bne r22, r23, tr1 + + /* + * Decompress the kernel. + */ + pt decompress_kernel, tr0 + blink tr0, r18 + + /* + * Disable the MMU. + */ + movi SR_HARMLESS, r22 + putcon r22, SSR + movi 1f, r22 + putcon r22, SPC + synco + rte /* And now go into the hyperspace ... */ +1: /* ... that's the next instruction ! */ + + /* Jump into the decompressed kernel */ + movi datalabel (CONFIG_MEMORY_START + 0x2000)+1, r19 + ptabs r19, tr0 + blink tr0, r18 + + /* Shouldn't return here, but just in case, loop forever */ + pt 1f, tr0 +1: blink tr0, r63 |