|  | /* | 
|  | * 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 program is free software; you can redistribute it and/or modify | 
|  | *    it under the terms of the GNU General Public License as published by | 
|  | *    the Free Software Foundation; either version 2, or (at your option) | 
|  | *    any later version. | 
|  | * | 
|  | *    This program is distributed in the hope that it will be useful, | 
|  | *    but WITHOUT ANY WARRANTY; without even the implied warranty of | 
|  | *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | 
|  | *    GNU General Public License for more details. | 
|  | * | 
|  | *    You should have received a copy of the GNU General Public License | 
|  | *    along with this program; if not, write to the Free Software | 
|  | *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA | 
|  | */ | 
|  |  | 
|  |  | 
|  | /* | 
|  | * 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 | 
|  | .data | 
|  |  | 
|  | #include <asm/assembly.h> | 
|  | #include <asm/pdc.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. | 
|  | */ | 
|  |  | 
|  | .align	PAGE_SIZE | 
|  | hpmc_stack: | 
|  | .block 16384 | 
|  |  | 
|  | #define HPMC_IODC_BUF_SIZE 0x8000 | 
|  |  | 
|  | .align	PAGE_SIZE | 
|  | hpmc_iodc_buf: | 
|  | .block HPMC_IODC_BUF_SIZE | 
|  |  | 
|  | .align 8 | 
|  | hpmc_raddr: | 
|  | .block 128 | 
|  |  | 
|  | #define HPMC_PIM_DATA_SIZE 896 /* Enough to hold all architected 2.0 state */ | 
|  |  | 
|  | .align 8 | 
|  | ENTRY(hpmc_pim_data) | 
|  | .block HPMC_PIM_DATA_SIZE | 
|  | END(hpmc_pim_data) | 
|  |  | 
|  | __HEAD | 
|  |  | 
|  | .import intr_save, code | 
|  | ENTRY(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. | 
|  | */ | 
|  |  | 
|  | ldo     8(%r0),%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 8,%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 | 
|  | ENDPROC(os_hpmc) | 
|  | ENTRY(os_hpmc_end)	/* this label used to compute os_hpmc checksum */ | 
|  | nop |