| /* SPDX-License-Identifier: GPL-2.0-only */ |
| /* |
| * s390x startup code |
| * |
| * Copyright (c) 2017 Red Hat Inc |
| * Copyright (c) 2019 IBM Corp. |
| * |
| * Authors: |
| * Thomas Huth <thuth@redhat.com> |
| * David Hildenbrand <david@redhat.com> |
| * Janosch Frank <frankja@linux.ibm.com> |
| */ |
| #include <asm/asm-offsets.h> |
| #include <asm/sigp.h> |
| |
| #include "macros.S" |
| .section .init |
| |
| /* |
| * Short init between 0x10000 and 0x10480 and then jump to 0x11000. |
| * 0x10480 - 0x11000 are written to by bootloader. |
| * |
| * For KVM and TCG kernel boot we are in 64 bit z/Arch mode. |
| * When booting from disk the initial short psw is in 31 bit mode. |
| * When running under LPAR or z/VM, we might start in 31 bit and esam mode. |
| */ |
| .globl start |
| start: |
| /* Switch to z/Architecture mode and 64-bit */ |
| slr %r0, %r0 # Set cpuid to zero |
| lhi %r1, 2 # mode 2 = esame |
| sigp %r1, %r0, SIGP_SET_ARCHITECTURE |
| /* XOR all registers with themselves to clear them fully. */ |
| .irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 |
| xgr \i,\i |
| .endr |
| sam64 # Set addressing mode to 64 bit |
| /* setup stack */ |
| larl %r15, stackptr |
| /* setup initial PSW mask + control registers*/ |
| larl %r1, initial_psw |
| lpswe 0(%r1) |
| clear_bss_start: |
| larl %r2, __bss_start |
| larl %r3, __bss_end |
| slgr %r3, %r2 # Get sizeof bss |
| aghi %r3,-1 |
| srlg %r4,%r3,8 # Calc number of 256 byte chunks |
| ltgr %r4,%r4 |
| lgr %r1,%r2 |
| jz clear_bss_remainder # If none, clear remaining bytes |
| clear_bss_loop: |
| xc 0(256,%r1), 0(%r1) # Clear 256 byte chunks via xor |
| la %r1, 256(%r1) |
| brctg %r4, clear_bss_loop |
| clear_bss_remainder: |
| larl %r2, memsetxc |
| ex %r3, 0(%r2) |
| /* setup pgm interrupt handler */ |
| larl %r1, pgm_int_psw |
| mvc GEN_LC_PGM_NEW_PSW(16), 0(%r1) |
| /* setup ext interrupt handler */ |
| larl %r1, ext_int_psw |
| mvc GEN_LC_EXT_NEW_PSW(16), 0(%r1) |
| /* setup mcck interrupt handler */ |
| larl %r1, mcck_int_psw |
| mvc GEN_LC_MCCK_NEW_PSW(16), 0(%r1) |
| /* setup io interrupt handler */ |
| larl %r1, io_int_psw |
| mvc GEN_LC_IO_NEW_PSW(16), 0(%r1) |
| /* setup svc interrupt handler */ |
| larl %r1, svc_int_psw |
| mvc GEN_LC_SVC_NEW_PSW(16), 0(%r1) |
| /* setup cr0, enabling e.g. AFP-register control */ |
| larl %r1, initial_cr0 |
| lctlg %c0, %c0, 0(%r1) |
| /* call setup() */ |
| brasl %r14, setup |
| /* forward test parameter */ |
| larl %r2, __argc |
| llgf %r2, 0(%r2) |
| larl %r3, __argv |
| /* call to main() */ |
| brasl %r14, main |
| /* forward exit code */ |
| lgr %r3, %r2 |
| /* call exit() */ |
| j exit |
| |
| memsetxc: |
| xc 0(1,%r1),0(%r1) |
| |
| .section .text |
| pgm_int: |
| CALL_INT_HANDLER handle_pgm_int, GEN_LC_PGM_OLD_PSW |
| |
| ext_int: |
| CALL_INT_HANDLER handle_ext_int, GEN_LC_EXT_OLD_PSW |
| |
| mcck_int: |
| CALL_INT_HANDLER handle_mcck_int, GEN_LC_MCCK_OLD_PSW |
| |
| io_int: |
| CALL_INT_HANDLER handle_io_int, GEN_LC_IO_OLD_PSW |
| |
| svc_int: |
| CALL_INT_HANDLER handle_svc_int, GEN_LC_SVC_OLD_PSW |
| |
| .align 8 |
| initial_psw: |
| .quad 0x0000000180000000, clear_bss_start |
| pgm_int_psw: |
| .quad 0x0000000180000000, pgm_int |
| ext_int_psw: |
| .quad 0x0000000180000000, ext_int |
| mcck_int_psw: |
| .quad 0x0000000180000000, mcck_int |
| io_int_psw: |
| .quad 0x0000000180000000, io_int |
| svc_int_psw: |
| .quad 0x0000000180000000, svc_int |
| .globl initial_cr0 |
| initial_cr0: |
| /* enable AFP-register control, so FP regs (+BFP instr) can be used */ |
| .quad 0x0000000000040000 |
