2 * HPMC (High Priority Machine Check) handler.
4 * Copyright (C) 1999 Philipp Rumpf <prumpf@tux.org>
5 * Copyright (C) 1999 Hewlett-Packard (Frank Rowand)
6 * Copyright (C) 2000 Hewlett-Packard (John Marvin)
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2, or (at your option)
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 * This HPMC handler retrieves the HPMC pim data, resets IO and
26 * returns to the default trap handler with code set to 1 (HPMC).
27 * The default trap handler calls handle interruption, which
28 * does a stack and register dump. This at least allows kernel
29 * developers to get back to C code in virtual mode, where they
30 * have the option to examine and print values from memory that
31 * would help in debugging an HPMC caused by a software bug.
33 * There is more to do here:
35 * 1) On MP systems we need to synchronize processors
36 * before calling pdc/iodc.
37 * 2) We should be checking the system state and not
38 * returning to the fault handler if things are really
47 #include <asm/assembly.h>
51 * stack for os_hpmc, the HPMC handler.
52 * buffer for IODC procedures (for the HPMC handler).
54 * IODC requires 7K byte stack. That leaves 1K byte for os_hpmc.
61 #define HPMC_IODC_BUF_SIZE 0x8000
65 .block HPMC_IODC_BUF_SIZE
71 #define HPMC_PIM_DATA_SIZE 896 /* Enough to hold all architected 2.0 state */
73 .export hpmc_pim_data, data
76 .block HPMC_PIM_DATA_SIZE
81 .import intr_save, code
88 * Using callee saves registers without saving them. The
89 * original values are in the pim dump if we need them.
91 * r2 (rp) return pointer
92 * r3 address of PDCE_PROC
95 * r23 (arg3) procedure arg
96 * r24 (arg2) procedure arg
97 * r25 (arg1) procedure arg
98 * r26 (arg0) procedure arg
99 * r30 (sp) stack pointer
103 * r26 contains address of PDCE_PROC on entry
104 * r28 (ret0) return value from procedure
107 copy arg0, %r3 /* save address of PDCE_PROC */
110 * disable nested HPMCs
112 * Increment os_hpmc checksum to invalidate it.
113 * Do this before turning the PSW M bit off.
121 /* MP_FIXME: synchronize all processors. */
123 /* Setup stack pointer. */
125 ldil L%PA(hpmc_stack),sp
126 ldo R%PA(hpmc_stack)(sp),sp
128 ldo 128(sp),sp /* leave room for arguments */
131 * Most PDC routines require that the M bit be off.
132 * So turn on the Q bit and turn off the M bit.
135 ldo 8(%r0),%r4 /* PSW Q on, PSW M off */
139 ldil L%PA(os_hpmc_1),%r4
140 ldo R%PA(os_hpmc_1)(%r4),%r4
149 /* Call PDC_PIM to get HPMC pim info */
152 * Note that on some newer boxes, PDC_PIM must be called
153 * before PDC_IO if you want IO to be reset. PDC_PIM sets
154 * a flag that PDC_IO examines.
157 ldo PDC_PIM(%r0), arg0
158 ldo PDC_PIM_HPMC(%r0),arg1 /* Transfer HPMC data */
159 ldil L%PA(hpmc_raddr),arg2
160 ldo R%PA(hpmc_raddr)(arg2),arg2
161 ldil L%PA(hpmc_pim_data),arg3
162 ldo R%PA(hpmc_pim_data)(arg3),arg3
163 ldil L%HPMC_PIM_DATA_SIZE,%r4
164 ldo R%HPMC_PIM_DATA_SIZE(%r4),%r4
167 ldil L%PA(os_hpmc_2), rp
168 bv (r3) /* call pdce_proc */
169 ldo R%PA(os_hpmc_2)(rp), rp
172 comib,<> 0,ret0, os_hpmc_fail
174 /* Reset IO by calling the hversion dependent PDC_IO routine */
177 ldo 0(%r0),arg1 /* log IO errors */
178 ldo 0(%r0),arg2 /* reserved */
179 ldo 0(%r0),arg3 /* reserved */
180 stw %r0,-52(sp) /* reserved */
182 ldil L%PA(os_hpmc_3),rp
183 bv (%r3) /* call pdce_proc */
184 ldo R%PA(os_hpmc_3)(rp),rp
188 /* FIXME? Check for errors from PDC_IO (-1 might be OK) */
191 * Initialize the IODC console device (HPA,SPA, path etc.
192 * are stored on page 0.
196 * Load IODC into hpmc_iodc_buf by calling PDC_IODC.
197 * Note that PDC_IODC handles flushing the appropriate
198 * data and instruction cache lines.
201 ldo PDC_IODC(%r0),arg0
202 ldo PDC_IODC_READ(%r0),arg1
203 ldil L%PA(hpmc_raddr),arg2
204 ldo R%PA(hpmc_raddr)(arg2),arg2
205 ldw BOOT_CONSOLE_HPA_OFFSET(%r0),arg3 /* console hpa */
206 ldo PDC_IODC_RI_INIT(%r0),%r4
208 ldil L%PA(hpmc_iodc_buf),%r4
209 ldo R%PA(hpmc_iodc_buf)(%r4),%r4
211 ldil L%HPMC_IODC_BUF_SIZE,%r4
212 ldo R%HPMC_IODC_BUF_SIZE(%r4),%r4
215 ldil L%PA(os_hpmc_4),rp
216 bv (%r3) /* call pdce_proc */
217 ldo R%PA(os_hpmc_4)(rp),rp
220 comib,<> 0,ret0,os_hpmc_fail
222 /* Call the entry init (just loaded by PDC_IODC) */
224 ldw BOOT_CONSOLE_HPA_OFFSET(%r0),arg0 /* console hpa */
225 ldo ENTRY_INIT_MOD_DEV(%r0), arg1
226 ldw BOOT_CONSOLE_SPA_OFFSET(%r0),arg2 /* console spa */
227 depi 0,31,11,arg2 /* clear bits 21-31 */
228 ldo BOOT_CONSOLE_PATH_OFFSET(%r0),arg3 /* console path */
229 ldil L%PA(hpmc_raddr),%r4
230 ldo R%PA(hpmc_raddr)(%r4),%r4
232 stw %r0, -56(sp) /* HV */
233 stw %r0, -60(sp) /* HV */
234 stw %r0, -64(sp) /* HV */
235 stw %r0, -68(sp) /* lang, must be zero */
237 ldil L%PA(hpmc_iodc_buf),%r5
238 ldo R%PA(hpmc_iodc_buf)(%r5),%r5
239 ldil L%PA(os_hpmc_5),rp
241 ldo R%PA(os_hpmc_5)(rp),rp
244 comib,<> 0,ret0,os_hpmc_fail
246 /* Prepare to call intr_save */
249 * Load kernel page directory (load into user also, since
250 * we don't intend to ever return to user land anyway)
253 ldil L%PA(swapper_pg_dir),%r4
254 ldo R%PA(swapper_pg_dir)(%r4),%r4
255 mtctl %r4,%cr24 /* Initialize kernel root pointer */
256 mtctl %r4,%cr25 /* Initialize user root pointer */
265 tovirt %r30 /* make sp virtual */
267 rsm 8,%r0 /* Clear Q bit */
269 mtctl %r1,%cr29 /* Set trap code to "1" for HPMC */
270 mtctl %r0,%cr30 /* Force interruptions to use hpmc stack */
271 ldil L%PA(intr_save), %r1
272 ldo R%PA(intr_save)(%r1), %r1
281 * Some systems may lockup from a broadcast reset, so try the
282 * hversion PDC_BROADCAST_RESET() first.
283 * MP_FIXME: reset all processors if more than one central bus.
286 /* PDC_BROADCAST_RESET() */
288 ldo PDC_BROADCAST_RESET(%r0),arg0
289 ldo 0(%r0),arg1 /* do reset */
291 ldil L%PA(os_hpmc_6),rp
292 bv (%r3) /* call pdce_proc */
293 ldo R%PA(os_hpmc_6)(rp),rp
298 * possible return values:
299 * -1 non-existent procedure
300 * -2 non-existent option
301 * -16 unaligned stack
303 * If call returned, do a broadcast reset.
306 ldil L%0xfffc0000,%r4 /* IO_BROADCAST */
308 stw %r5,48(%r4) /* CMD_RESET to IO_COMMAND offset */
313 /* this label used to compute os_hpmc checksum */
315 .export os_hpmc_end, code