1 /* $NetBSD: acpi_pci_smccc.c,v 1.2 2022/10/15 10:45:40 jmcneill Exp $ */
2
3 /*-
4 * Copyright (c) 2021 Jared McNeill <jmcneill@invisible.ca>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: acpi_pci_smccc.c,v 1.2 2022/10/15 10:45:40 jmcneill Exp $");
31
32 #include <sys/param.h>
33 #include <sys/kernel.h>
34
35 #include <dev/pci/pcireg.h>
36 #include <dev/pci/pcivar.h>
37 #include <dev/pci/pciconf.h>
38
39 #include <dev/acpi/acpivar.h>
40 #include <dev/acpi/acpi_pci.h>
41 #include <dev/acpi/acpi_mcfg.h>
42
43 #include <arm/acpi/acpi_pci_machdep.h>
44
45 #include <arm/pci/pci_smccc.h>
46
47 static int
acpi_pci_smccc_conf_read(pci_chipset_tag_t pc,pcitag_t tag,int reg,pcireg_t * data)48 acpi_pci_smccc_conf_read(pci_chipset_tag_t pc, pcitag_t tag, int reg,
49 pcireg_t *data)
50 {
51 struct acpi_pci_context *ap = pc->pc_conf_v;
52 int b, d, f;
53 int status;
54
55 pci_decompose_tag(pc, tag, &b, &d, &f);
56
57 if (b < ap->ap_bus || b > ap->ap_maxbus) {
58 *data = -1;
59 return EINVAL;
60 }
61
62 status = pci_smccc_read(PCI_SMCCC_SBDF(ap->ap_seg, b, d, f), reg,
63 PCI_SMCCC_ACCESS_32BIT, data);
64 if (!PCI_SMCCC_SUCCESS(status)) {
65 *data = -1;
66 return EINVAL;
67 }
68
69 return 0;
70 }
71
72 static int
acpi_pci_smccc_conf_write(pci_chipset_tag_t pc,pcitag_t tag,int reg,pcireg_t data)73 acpi_pci_smccc_conf_write(pci_chipset_tag_t pc, pcitag_t tag, int reg,
74 pcireg_t data)
75 {
76 struct acpi_pci_context *ap = pc->pc_conf_v;
77 int b, d, f;
78 int status;
79
80 pci_decompose_tag(pc, tag, &b, &d, &f);
81
82 if (b < ap->ap_bus || b > ap->ap_maxbus) {
83 return EINVAL;
84 }
85
86 status = pci_smccc_write(PCI_SMCCC_SBDF(ap->ap_seg, b, d, f), reg,
87 PCI_SMCCC_ACCESS_32BIT, data);
88 if (!PCI_SMCCC_SUCCESS(status)) {
89 return EINVAL;
90 }
91
92 return 0;
93 }
94
95
96 void
acpi_pci_smccc_init(struct acpi_pci_context * ap)97 acpi_pci_smccc_init(struct acpi_pci_context *ap)
98 {
99 int status, ver;
100 uint8_t bus_start, bus_end;
101 uint16_t next_seg;
102
103 ver = pci_smccc_version();
104 if (!PCI_SMCCC_SUCCESS(ver)) {
105 aprint_error_dev(ap->ap_dev,
106 "SMCCC: PCI_VERSION call failed, status %#x\n", ver);
107 return;
108 }
109 aprint_normal_dev(ap->ap_dev, "SMCCC: PCI impl. version %u.%u\n",
110 (ver >> 16) & 0x7fff, ver & 0xffff);
111
112 status = pci_smccc_get_seg_info(ap->ap_seg, &bus_start, &bus_end,
113 &next_seg);
114 if (!PCI_SMCCC_SUCCESS(status)) {
115 aprint_error_dev(ap->ap_dev,
116 "SMCCC: No info for segment %u, status %#x\n",
117 ap->ap_seg, status);
118 return;
119 }
120 aprint_normal_dev(ap->ap_dev, "SMCCC: segment %u, bus %u-%u\n",
121 ap->ap_seg, bus_start, bus_end);
122
123 ap->ap_bus = bus_start;
124 ap->ap_maxbus = bus_end;
125 ap->ap_conf_read = acpi_pci_smccc_conf_read;
126 ap->ap_conf_write = acpi_pci_smccc_conf_write;
127 ap->ap_flags |= ACPI_PCI_FLAG_NO_MCFG;
128 ap->ap_pciflags_clear = PCI_FLAGS_MSI_OKAY | PCI_FLAGS_MSIX_OKAY;
129 }
130