xref: /illumos-gate/usr/src/uts/i86pc/cpu/amd_opteron/ao_cpu.c (revision 66582b606a8194f7f3ba5b3a3a6dca5b0d346361)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include <sys/types.h>
28 #include <sys/pghw.h>
29 #include <sys/cmn_err.h>
30 #include <sys/sysmacros.h>
31 #include <sys/fm/protocol.h>
32 #include <sys/x86_archext.h>
33 #include <sys/pci_cfgspace.h>
34 
35 #include "ao.h"
36 
37 /*
38  * AMD Opteron CPU Subroutines
39  *
40  * The following two tunables are used to determine the scrubbing rates for
41  * the D$ and L2$.  The values range from 0x00-0x16 as described in BKDG
42  * Scrub Control Register.  A value of zero disables the scrubber.  Values
43  * above zero indicate rates in descending order.
44  *
45  * The current default values are used on several Sun systems.  In the future
46  * this code should assign values dynamically based on cache sizing.  If you
47  * tune these values manually be aware of the following architectural issue:
48  * At present, Opteron can only survive certain kinds of multi-bit errors if
49  * they are detected by the scrubbers.  Therefore in general we want these
50  * values tuned as high as possible without impacting workload performance.
51  */
52 uint32_t ao_scrub_rate_dcache = 8;	/* 64B every 5.12 us */
53 uint32_t ao_scrub_rate_l2cache = 9;	/* 64B every 10.2 us */
54 
55 enum {
56 	AO_SCRUB_BIOSDEFAULT,		/* retain system default values */
57 	AO_SCRUB_FIXED,			/* assign ao_scrub_rate_* values */
58 	AO_SCRUB_MAX			/* assign max of system and tunables */
59 } ao_scrub_policy = AO_SCRUB_MAX;
60 
61 void
62 ao_pcicfg_write(uint_t procnodeid, uint_t func, uint_t reg, uint32_t val)
63 {
64 	ASSERT(procnodeid + 24 <= 31);
65 	ASSERT((func & 7) == func);
66 	ASSERT((reg & 3) == 0 && reg < 256);
67 
68 	cmi_pci_putl(0, procnodeid + 24, func, reg, 0, val);
69 }
70 
71 uint32_t
72 ao_pcicfg_read(uint_t procnodeid, uint_t func, uint_t reg)
73 {
74 	ASSERT(procnodeid + 24 <= 31);
75 	ASSERT((func & 7) == func);
76 	ASSERT((reg & 3) == 0 && reg < 256);
77 
78 	return (cmi_pci_getl(0, procnodeid + 24, func, reg, 0, 0));
79 }
80 
81 
82 /*
83  * Return the maximum scrubbing rate between r1 and r2, where r2 is extracted
84  * from the specified 'cfg' register value using 'mask' and 'shift'.  If a
85  * value is zero, scrubbing is off so return the opposite value.  Otherwise
86  * the maximum rate is the smallest non-zero value of the two values.
87  */
88 static uint32_t
89 ao_scrubber_max(uint32_t r1, uint32_t r2)
90 {
91 	if (r1 != 0 && r2 != 0)
92 		return (MIN(r1, r2));
93 
94 	return (r1 ? r1 : r2);
95 }
96 
97 /*
98  * Enable the node-specific hardware scrubbers for the D$ and L2$.  We set
99  * the scrubber rate based on a set of tunables defined at the top of the file.
100  */
101 void
102 ao_procnode_scrubber_enable(cmi_hdl_t hdl, ao_ms_data_t *ao)
103 {
104 	uint_t procnodeid = cmi_hdl_procnodeid(hdl);
105 	union mcreg_scrubctl scrubctl;
106 
107 	ao->ao_ms_shared->aos_bcfg_scrubctl = MCREG_VAL32(&scrubctl) =
108 	    ao_pcicfg_read(procnodeid, MC_FUNC_MISCCTL, MC_CTL_REG_SCRUBCTL);
109 
110 	if (ao_scrub_policy == AO_SCRUB_BIOSDEFAULT)
111 		return;
112 
113 	if (ao_scrub_rate_dcache > AMD_NB_SCRUBCTL_RATE_MAX) {
114 		cmn_err(CE_WARN, "ao_scrub_rate_dcache is too large; "
115 		    "resetting to 0x%x\n", AMD_NB_SCRUBCTL_RATE_MAX);
116 		ao_scrub_rate_dcache = AMD_NB_SCRUBCTL_RATE_MAX;
117 	}
118 
119 	if (ao_scrub_rate_l2cache > AMD_NB_SCRUBCTL_RATE_MAX) {
120 		cmn_err(CE_WARN, "ao_scrub_rate_l2cache is too large; "
121 		    "resetting to 0x%x\n", AMD_NB_SCRUBCTL_RATE_MAX);
122 		ao_scrub_rate_l2cache = AMD_NB_SCRUBCTL_RATE_MAX;
123 	}
124 
125 	switch (ao_scrub_policy) {
126 	case AO_SCRUB_FIXED:
127 		/* Use the system values checked above */
128 		break;
129 
130 	default:
131 		cmn_err(CE_WARN, "Unknown ao_scrub_policy value %d - "
132 		    "using default policy of AO_SCRUB_MAX", ao_scrub_policy);
133 		/*FALLTHRU*/
134 
135 	case AO_SCRUB_MAX:
136 		ao_scrub_rate_dcache =
137 		    ao_scrubber_max(ao_scrub_rate_dcache,
138 		    MCREG_FIELD_CMN(&scrubctl, DcacheScrub));
139 
140 		ao_scrub_rate_l2cache =
141 		    ao_scrubber_max(ao_scrub_rate_l2cache,
142 		    MCREG_FIELD_CMN(&scrubctl, L2Scrub));
143 		break;
144 	}
145 
146 	MCREG_FIELD_CMN(&scrubctl, DcacheScrub) = ao_scrub_rate_dcache;
147 	MCREG_FIELD_CMN(&scrubctl, L2Scrub) = ao_scrub_rate_l2cache;
148 
149 	ao_pcicfg_write(procnodeid, MC_FUNC_MISCCTL, MC_CTL_REG_SCRUBCTL,
150 	    MCREG_VAL32(&scrubctl));
151 }
152