xref: /illumos-gate/usr/src/uts/i86pc/os/pci_mech1_amd.c (revision dd72704bd9e794056c558153663c739e2012d721)
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  * Copyright 2010 Advanced Micro Devices, Inc.
23  * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
24  * Copyright 2022 Oxide Computer Company
25  */
26 
27 /*
28  * PCI Mechanism 1 low-level routines with ECS support for AMD family >= 0x10
29  */
30 
31 #include <sys/controlregs.h>
32 #include <sys/cpuvar.h>
33 #include <sys/types.h>
34 #include <sys/pci.h>
35 #include <sys/pci_impl.h>
36 #include <sys/sunddi.h>
37 #include <sys/pci_cfgspace_impl.h>
38 #include <sys/x86_archext.h>
39 
40 boolean_t
41 pci_check_amd_ioecs(void)
42 {
43 	struct cpuid_regs cp;
44 	int family;
45 
46 	ASSERT(is_x86_feature(x86_featureset, X86FSET_CPUID));
47 
48 	/*
49 	 * Get the CPU vendor string from CPUID.
50 	 * This PCI mechanism only applies to AMD CPUs.
51 	 */
52 	cp.cp_eax = 0;
53 	(void) __cpuid_insn(&cp);
54 
55 	if ((cp.cp_ebx != 0x68747541) || /* Auth */
56 	    (cp.cp_edx != 0x69746e65) || /* enti */
57 	    (cp.cp_ecx != 0x444d4163))   /* cAMD */
58 		return (B_FALSE);
59 
60 	/*
61 	 * Get the CPU family from CPUID.
62 	 * This PCI mechanism is only available on family 0x10 or higher.
63 	 */
64 	cp.cp_eax = 1;
65 	(void) __cpuid_insn(&cp);
66 	family = ((cp.cp_eax >> 8) & 0xf) + ((cp.cp_eax >> 20) & 0xff);
67 
68 	if (family < 0x10)
69 		return (B_FALSE);
70 
71 	/*
72 	 * Set the EnableCf8ExtCfg bit in the Northbridge Configuration Register
73 	 * to enable accessing PCI ECS using in/out instructions.
74 	 */
75 	wrmsr(MSR_AMD_NB_CFG, rdmsr(MSR_AMD_NB_CFG) | AMD_GH_NB_CFG_EN_ECS);
76 	return (B_TRUE);
77 }
78 
79 /*
80  * Macro to setup PCI Extended Configuration Space (ECS) address to give to
81  * "in/out" instructions
82  */
83 #define	PCI_CADDR1_ECS(b, d, f, r) \
84 	(PCI_CADDR1((b), (d), (f), (r)) | ((((r) >> 8) & 0xf) << 24))
85 
86 /*
87  * Per PCI 2.1 section 3.7.4.1 and PCI-PCI Bridge Architecture 1.0 section
88  * 5.3.1.2:  dev=31 func=7 reg=0 means a special cycle.  We don't want to
89  * trigger that by accident, so we pretend that dev 31, func 7 doesn't
90  * exist.  If we ever want special cycle support, we'll add explicit
91  * special cycle support.
92  */
93 
94 uint8_t
95 pci_mech1_amd_getb(int bus, int device, int function, int reg)
96 {
97 	uint8_t val;
98 
99 	if (device == PCI_MECH1_SPEC_CYCLE_DEV &&
100 	    function == PCI_MECH1_SPEC_CYCLE_FUNC) {
101 		return (PCI_EINVAL8);
102 	}
103 
104 	if (reg > pci_iocfg_max_offset) {
105 		return (PCI_EINVAL8);
106 	}
107 
108 	mutex_enter(&pcicfg_mutex);
109 	outl(PCI_CONFADD, PCI_CADDR1_ECS(bus, device, function, reg));
110 	val = inb(PCI_CONFDATA | (reg & 0x3));
111 	mutex_exit(&pcicfg_mutex);
112 	return (val);
113 }
114 
115 uint16_t
116 pci_mech1_amd_getw(int bus, int device, int function, int reg)
117 {
118 	uint16_t val;
119 
120 	if (device == PCI_MECH1_SPEC_CYCLE_DEV &&
121 	    function == PCI_MECH1_SPEC_CYCLE_FUNC) {
122 		return (PCI_EINVAL16);
123 	}
124 
125 	if (reg > pci_iocfg_max_offset) {
126 		return (PCI_EINVAL16);
127 	}
128 
129 	mutex_enter(&pcicfg_mutex);
130 	outl(PCI_CONFADD, PCI_CADDR1_ECS(bus, device, function, reg));
131 	val =  inw(PCI_CONFDATA | (reg & 0x2));
132 	mutex_exit(&pcicfg_mutex);
133 	return (val);
134 }
135 
136 uint32_t
137 pci_mech1_amd_getl(int bus, int device, int function, int reg)
138 {
139 	uint32_t val;
140 
141 	if (device == PCI_MECH1_SPEC_CYCLE_DEV &&
142 	    function == PCI_MECH1_SPEC_CYCLE_FUNC) {
143 		return (PCI_EINVAL32);
144 	}
145 
146 	if (reg > pci_iocfg_max_offset) {
147 		return (PCI_EINVAL32);
148 	}
149 
150 	mutex_enter(&pcicfg_mutex);
151 	outl(PCI_CONFADD, PCI_CADDR1_ECS(bus, device, function, reg));
152 	val = inl(PCI_CONFDATA);
153 	mutex_exit(&pcicfg_mutex);
154 	return (val);
155 }
156 
157 void
158 pci_mech1_amd_putb(int bus, int device, int function, int reg, uint8_t val)
159 {
160 	if (device == PCI_MECH1_SPEC_CYCLE_DEV &&
161 	    function == PCI_MECH1_SPEC_CYCLE_FUNC) {
162 		return;
163 	}
164 
165 	mutex_enter(&pcicfg_mutex);
166 	outl(PCI_CONFADD, PCI_CADDR1_ECS(bus, device, function, reg));
167 	outb(PCI_CONFDATA | (reg & 0x3), val);
168 	mutex_exit(&pcicfg_mutex);
169 }
170 
171 void
172 pci_mech1_amd_putw(int bus, int device, int function, int reg, uint16_t val)
173 {
174 	if (device == PCI_MECH1_SPEC_CYCLE_DEV &&
175 	    function == PCI_MECH1_SPEC_CYCLE_FUNC) {
176 		return;
177 	}
178 
179 	mutex_enter(&pcicfg_mutex);
180 	outl(PCI_CONFADD, PCI_CADDR1_ECS(bus, device, function, reg));
181 	outw(PCI_CONFDATA | (reg & 0x2), val);
182 	mutex_exit(&pcicfg_mutex);
183 }
184 
185 void
186 pci_mech1_amd_putl(int bus, int device, int function, int reg, uint32_t val)
187 {
188 	if (device == PCI_MECH1_SPEC_CYCLE_DEV &&
189 	    function == PCI_MECH1_SPEC_CYCLE_FUNC) {
190 		return;
191 	}
192 
193 	mutex_enter(&pcicfg_mutex);
194 	outl(PCI_CONFADD, PCI_CADDR1_ECS(bus, device, function, reg));
195 	outl(PCI_CONFDATA, val);
196 	mutex_exit(&pcicfg_mutex);
197 }
198