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
47static int
48acpi_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
72static int
73acpi_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
96void
97acpi_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