| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| /* |
| * HPMC (High Priority Machine Check) handler. |
| * |
| * Copyright (C) 1999 Philipp Rumpf <prumpf@tux.org> |
| * Copyright (C) 1999 Hewlett-Packard (Frank Rowand) |
| * Copyright (C) 2000 Hewlett-Packard (John Marvin) |
| */ |
| |
| |
| /* |
| * This HPMC handler retrieves the HPMC pim data, resets IO and |
| * returns to the default trap handler with code set to 1 (HPMC). |
| * The default trap handler calls handle interruption, which |
| * does a stack and register dump. This at least allows kernel |
| * developers to get back to C code in virtual mode, where they |
| * have the option to examine and print values from memory that |
| * would help in debugging an HPMC caused by a software bug. |
| * |
| * There is more to do here: |
| * |
| * 1) On MP systems we need to synchronize processors |
| * before calling pdc/iodc. |
| * 2) We should be checking the system state and not |
| * returning to the fault handler if things are really |
| * bad. |
| * |
| */ |
| |
| .level 1.1 |
| |
| #include <asm/assembly.h> |
| #include <asm/pdc.h> |
| #include <asm/psw.h> |
| |
| #include <linux/linkage.h> |
| #include <linux/init.h> |
| |
| /* |
| * stack for os_hpmc, the HPMC handler. |
| * buffer for IODC procedures (for the HPMC handler). |
| * |
| * IODC requires 7K byte stack. That leaves 1K byte for os_hpmc. |
| */ |
| |
| .import toc_stack,data |
| #define hpmc_stack toc_stack /* re-use the TOC stack */ |
| |
| #define HPMC_IODC_BUF_SIZE 0x8000 |
| |
| __PAGE_ALIGNED_BSS |
| .align 4096 |
| hpmc_iodc_buf: |
| .block HPMC_IODC_BUF_SIZE |
| |
| .section .bss |
| .align 8 |
| hpmc_raddr: |
| .block 128 |
| |
| #define HPMC_PIM_DATA_SIZE 896 /* Enough to hold all architected 2.0 state */ |
| |
| .section .bss |
| .align 8 |
| ENTRY(hpmc_pim_data) |
| .block HPMC_PIM_DATA_SIZE |
| END(hpmc_pim_data) |
| |
| .text |
| |
| .import intr_save, code |
| .align 16 |
| ENTRY(os_hpmc) |
| .os_hpmc: |
| |
| /* |
| * registers modified: |
| * |
| * Using callee saves registers without saving them. The |
| * original values are in the pim dump if we need them. |
| * |
| * r2 (rp) return pointer |
| * r3 address of PDCE_PROC |
| * r4 scratch |
| * r5 scratch |
| * r23 (arg3) procedure arg |
| * r24 (arg2) procedure arg |
| * r25 (arg1) procedure arg |
| * r26 (arg0) procedure arg |
| * r30 (sp) stack pointer |
| * |
| * registers read: |
| * |
| * r26 contains address of PDCE_PROC on entry |
| * r28 (ret0) return value from procedure |
| */ |
| |
| copy arg0, %r3 /* save address of PDCE_PROC */ |
| |
| /* |
| * disable nested HPMCs |
| * |
| * Increment os_hpmc checksum to invalidate it. |
| * Do this before turning the PSW M bit off. |
| */ |
| |
| mfctl %cr14, %r4 |
| ldw 52(%r4),%r5 |
| addi 1,%r5,%r5 |
| stw %r5,52(%r4) |
| |
| /* MP_FIXME: synchronize all processors. */ |
| |
| /* Setup stack pointer. */ |
| |
| load32 PA(hpmc_stack),sp |
| |
| ldo 128(sp),sp /* leave room for arguments */ |
| |
| /* |
| * Most PDC routines require that the M bit be off. |
| * So turn on the Q bit and turn off the M bit. |
| */ |
| |
| ldi PSW_SM_Q,%r4 /* PSW Q on, PSW M off */ |
| mtctl %r4,ipsw |
| mtctl %r0,pcsq |
| mtctl %r0,pcsq |
| load32 PA(os_hpmc_1),%r4 |
| mtctl %r4,pcoq |
| ldo 4(%r4),%r4 |
| mtctl %r4,pcoq |
| rfi |
| nop |
| |
| os_hpmc_1: |
| |
| /* Call PDC_PIM to get HPMC pim info */ |
| |
| /* |
| * Note that on some newer boxes, PDC_PIM must be called |
| * before PDC_IO if you want IO to be reset. PDC_PIM sets |
| * a flag that PDC_IO examines. |
| */ |
| |
| ldo PDC_PIM(%r0), arg0 |
| ldo PDC_PIM_HPMC(%r0),arg1 /* Transfer HPMC data */ |
| load32 PA(hpmc_raddr),arg2 |
| load32 PA(hpmc_pim_data),arg3 |
| load32 HPMC_PIM_DATA_SIZE,%r4 |
| stw %r4,-52(sp) |
| |
| ldil L%PA(os_hpmc_2), rp |
| bv (r3) /* call pdce_proc */ |
| ldo R%PA(os_hpmc_2)(rp), rp |
| |
| os_hpmc_2: |
| comib,<> 0,ret0, os_hpmc_fail |
| |
| /* Reset IO by calling the hversion dependent PDC_IO routine */ |
| |
| ldo PDC_IO(%r0),arg0 |
| ldo 0(%r0),arg1 /* log IO errors */ |
| ldo 0(%r0),arg2 /* reserved */ |
| ldo 0(%r0),arg3 /* reserved */ |
| stw %r0,-52(sp) /* reserved */ |
| |
| ldil L%PA(os_hpmc_3),rp |
| bv (%r3) /* call pdce_proc */ |
| ldo R%PA(os_hpmc_3)(rp),rp |
| |
| os_hpmc_3: |
| |
| /* FIXME? Check for errors from PDC_IO (-1 might be OK) */ |
| |
| /* |
| * Initialize the IODC console device (HPA,SPA, path etc. |
| * are stored on page 0. |
| */ |
| |
| /* |
| * Load IODC into hpmc_iodc_buf by calling PDC_IODC. |
| * Note that PDC_IODC handles flushing the appropriate |
| * data and instruction cache lines. |
| */ |
| |
| ldo PDC_IODC(%r0),arg0 |
| ldo PDC_IODC_READ(%r0),arg1 |
| load32 PA(hpmc_raddr),arg2 |
| ldw BOOT_CONSOLE_HPA_OFFSET(%r0),arg3 /* console hpa */ |
| ldo PDC_IODC_RI_INIT(%r0),%r4 |
| stw %r4,-52(sp) |
| load32 PA(hpmc_iodc_buf),%r4 |
| stw %r4,-56(sp) |
| load32 HPMC_IODC_BUF_SIZE,%r4 |
| stw %r4,-60(sp) |
| |
| ldil L%PA(os_hpmc_4),rp |
| bv (%r3) /* call pdce_proc */ |
| ldo R%PA(os_hpmc_4)(rp),rp |
| |
| os_hpmc_4: |
| comib,<> 0,ret0,os_hpmc_fail |
| |
| /* Call the entry init (just loaded by PDC_IODC) */ |
| |
| ldw BOOT_CONSOLE_HPA_OFFSET(%r0),arg0 /* console hpa */ |
| ldo ENTRY_INIT_MOD_DEV(%r0), arg1 |
| ldw BOOT_CONSOLE_SPA_OFFSET(%r0),arg2 /* console spa */ |
| depi 0,31,11,arg2 /* clear bits 21-31 */ |
| ldo BOOT_CONSOLE_PATH_OFFSET(%r0),arg3 /* console path */ |
| load32 PA(hpmc_raddr),%r4 |
| stw %r4, -52(sp) |
| stw %r0, -56(sp) /* HV */ |
| stw %r0, -60(sp) /* HV */ |
| stw %r0, -64(sp) /* HV */ |
| stw %r0, -68(sp) /* lang, must be zero */ |
| |
| load32 PA(hpmc_iodc_buf),%r5 |
| ldil L%PA(os_hpmc_5),rp |
| bv (%r5) |
| ldo R%PA(os_hpmc_5)(rp),rp |
| |
| os_hpmc_5: |
| comib,<> 0,ret0,os_hpmc_fail |
| |
| /* Prepare to call intr_save */ |
| |
| /* |
| * Load kernel page directory (load into user also, since |
| * we don't intend to ever return to user land anyway) |
| */ |
| |
| load32 PA(swapper_pg_dir),%r4 |
| mtctl %r4,%cr24 /* Initialize kernel root pointer */ |
| mtctl %r4,%cr25 /* Initialize user root pointer */ |
| |
| /* Clear sr4-sr7 */ |
| |
| mtsp %r0, %sr4 |
| mtsp %r0, %sr5 |
| mtsp %r0, %sr6 |
| mtsp %r0, %sr7 |
| |
| tovirt_r1 %r30 /* make sp virtual */ |
| |
| rsm PSW_SM_Q,%r0 /* Clear Q bit */ |
| ldi 1,%r8 /* Set trap code to "1" for HPMC */ |
| load32 PA(intr_save),%r1 |
| be 0(%sr7,%r1) |
| nop |
| |
| os_hpmc_fail: |
| |
| /* |
| * Reset the system |
| * |
| * Some systems may lockup from a broadcast reset, so try the |
| * hversion PDC_BROADCAST_RESET() first. |
| * MP_FIXME: reset all processors if more than one central bus. |
| */ |
| |
| /* PDC_BROADCAST_RESET() */ |
| |
| ldo PDC_BROADCAST_RESET(%r0),arg0 |
| ldo 0(%r0),arg1 /* do reset */ |
| |
| ldil L%PA(os_hpmc_6),rp |
| bv (%r3) /* call pdce_proc */ |
| ldo R%PA(os_hpmc_6)(rp),rp |
| |
| os_hpmc_6: |
| |
| /* |
| * possible return values: |
| * -1 non-existent procedure |
| * -2 non-existent option |
| * -16 unaligned stack |
| * |
| * If call returned, do a broadcast reset. |
| */ |
| |
| ldil L%0xfffc0000,%r4 /* IO_BROADCAST */ |
| ldo 5(%r0),%r5 |
| stw %r5,48(%r4) /* CMD_RESET to IO_COMMAND offset */ |
| |
| b . |
| nop |
| .align 16 /* make function length multiple of 16 bytes */ |
