diff options
| author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
|---|---|---|
| committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
| commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
| tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /arch/powerpc/kernel/prom_entry_64.S | |
| parent | Initial commit. (diff) | |
| download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip | |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/kernel/prom_entry_64.S')
| -rw-r--r-- | arch/powerpc/kernel/prom_entry_64.S | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/prom_entry_64.S b/arch/powerpc/kernel/prom_entry_64.S new file mode 100644 index 0000000000..f1b8793d28 --- /dev/null +++ b/arch/powerpc/kernel/prom_entry_64.S @@ -0,0 +1,87 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * PowerPC version + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP + * Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu> + * Adapted for Power Macintosh by Paul Mackerras. + * Low-level exception handlers and MMU support + * rewritten by Paul Mackerras. + * Copyright (C) 1996 Paul Mackerras. + * MPC8xx modifications Copyright (C) 1997 Dan Malek (dmalek@jlc.net). + * + * This file contains the 64-bit prom entry code. + */ +#include <asm/asm-offsets.h> +#ifdef CONFIG_PPC_BOOK3S +#include <asm/exception-64s.h> +#else +#include <asm/exception-64e.h> +#endif +#include <asm/ppc_asm.h> + +.section ".text","ax",@progbits + +_GLOBAL(enter_prom) + mflr r0 + std r0,16(r1) + stdu r1,-SWITCH_FRAME_SIZE(r1) /* Save SP and create stack space */ + + /* Because PROM is running in 32b mode, it clobbers the high order half + * of all registers that it saves. We therefore save those registers + * PROM might touch to the stack. (r0, r3-r13 are caller saved) + */ + SAVE_GPR(2, r1) + SAVE_GPR(13, r1) + SAVE_NVGPRS(r1) + mfcr r10 + mfmsr r11 + std r10,_CCR(r1) + std r11,_MSR(r1) + + /* Put PROM address in SRR0 */ + mtsrr0 r4 + + /* Setup our trampoline return addr in LR */ + bcl 20,31,$+4 +0: mflr r4 + addi r4,r4,(1f - 0b) + mtlr r4 + + /* Prepare a 32-bit mode big endian MSR + */ +#ifdef CONFIG_PPC_BOOK3E_64 + rlwinm r11,r11,0,1,31 + mtsrr1 r11 + rfi +#else /* CONFIG_PPC_BOOK3E_64 */ + LOAD_REG_IMMEDIATE(r12, MSR_SF | MSR_LE) + andc r11,r11,r12 + mtsrr1 r11 + RFI_TO_KERNEL +#endif /* CONFIG_PPC_BOOK3E_64 */ + +1: /* Return from OF */ + FIXUP_ENDIAN + + /* Just make sure that r1 top 32 bits didn't get + * corrupt by OF + */ + rldicl r1,r1,0,32 + + /* Restore the MSR (back to 64 bits) */ + ld r0,_MSR(r1) + MTMSRD(r0) + isync + + /* Restore other registers */ + REST_GPR(2, r1) + REST_GPR(13, r1) + REST_NVGPRS(r1) + ld r4,_CCR(r1) + mtcr r4 + + addi r1,r1,SWITCH_FRAME_SIZE + ld r0,16(r1) + mtlr r0 + blr |