blob: e6c80ac076974e491264a51b2c33dc3d6ff5188d [file] [log] [blame]
Michael Ellerman85f2bf92007-05-08 12:58:35 +10001/*
2 * Copyright 2006 Jake Moilanen <moilanen@austin.ibm.com>, IBM Corp.
3 * Copyright 2006-2007 Michael Ellerman, IBM Corp.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; version 2 of the
8 * License.
9 *
10 */
11
12#include <linux/device.h>
13#include <linux/irq.h>
14#include <linux/msi.h>
15
16#include <asm/rtas.h>
17#include <asm/hw_irq.h>
18#include <asm/ppc-pci.h>
19
20static int query_token, change_token;
21
22#define RTAS_QUERY_FN 0
23#define RTAS_CHANGE_FN 1
24#define RTAS_RESET_FN 2
25#define RTAS_CHANGE_MSI_FN 3
26#define RTAS_CHANGE_MSIX_FN 4
27
28static struct pci_dn *get_pdn(struct pci_dev *pdev)
29{
30 struct device_node *dn;
31 struct pci_dn *pdn;
32
33 dn = pci_device_to_OF_node(pdev);
34 if (!dn) {
35 dev_dbg(&pdev->dev, "rtas_msi: No OF device node\n");
36 return NULL;
37 }
38
39 pdn = PCI_DN(dn);
40 if (!pdn) {
41 dev_dbg(&pdev->dev, "rtas_msi: No PCI DN\n");
42 return NULL;
43 }
44
45 return pdn;
46}
47
48/* RTAS Helpers */
49
50static int rtas_change_msi(struct pci_dn *pdn, u32 func, u32 num_irqs)
51{
52 u32 addr, seq_num, rtas_ret[3];
53 unsigned long buid;
54 int rc;
55
56 addr = rtas_config_addr(pdn->busno, pdn->devfn, 0);
57 buid = pdn->phb->buid;
58
59 seq_num = 1;
60 do {
61 if (func == RTAS_CHANGE_MSI_FN || func == RTAS_CHANGE_MSIX_FN)
62 rc = rtas_call(change_token, 6, 4, rtas_ret, addr,
63 BUID_HI(buid), BUID_LO(buid),
64 func, num_irqs, seq_num);
65 else
66 rc = rtas_call(change_token, 6, 3, rtas_ret, addr,
67 BUID_HI(buid), BUID_LO(buid),
68 func, num_irqs, seq_num);
69
70 seq_num = rtas_ret[1];
71 } while (rtas_busy_delay(rc));
72
Michael Ellermand3853662007-09-20 16:36:50 +100073 /*
74 * If the RTAS call succeeded, check the number of irqs is actually
75 * what we asked for. If not, return an error.
76 */
77 if (rc == 0 && rtas_ret[0] != num_irqs)
78 rc = -ENOSPC;
Michael Ellerman85f2bf92007-05-08 12:58:35 +100079
Michael Ellermand3853662007-09-20 16:36:50 +100080 pr_debug("rtas_msi: ibm,change_msi(func=%d,num=%d), got %d rc = %d\n",
81 func, num_irqs, rtas_ret[0], rc);
Michael Ellerman85f2bf92007-05-08 12:58:35 +100082
83 return rc;
84}
85
86static void rtas_disable_msi(struct pci_dev *pdev)
87{
88 struct pci_dn *pdn;
89
90 pdn = get_pdn(pdev);
91 if (!pdn)
92 return;
93
Michael Ellermand3853662007-09-20 16:36:50 +100094 if (rtas_change_msi(pdn, RTAS_CHANGE_FN, 0))
Michael Ellerman85f2bf92007-05-08 12:58:35 +100095 pr_debug("rtas_msi: Setting MSIs to 0 failed!\n");
96}
97
98static int rtas_query_irq_number(struct pci_dn *pdn, int offset)
99{
100 u32 addr, rtas_ret[2];
101 unsigned long buid;
102 int rc;
103
104 addr = rtas_config_addr(pdn->busno, pdn->devfn, 0);
105 buid = pdn->phb->buid;
106
107 do {
108 rc = rtas_call(query_token, 4, 3, rtas_ret, addr,
109 BUID_HI(buid), BUID_LO(buid), offset);
110 } while (rtas_busy_delay(rc));
111
112 if (rc) {
113 pr_debug("rtas_msi: error (%d) querying source number\n", rc);
114 return rc;
115 }
116
117 return rtas_ret[0];
118}
119
120static void rtas_teardown_msi_irqs(struct pci_dev *pdev)
121{
122 struct msi_desc *entry;
123
124 list_for_each_entry(entry, &pdev->msi_list, list) {
125 if (entry->irq == NO_IRQ)
126 continue;
127
128 set_irq_msi(entry->irq, NULL);
129 irq_dispose_mapping(entry->irq);
130 }
131
132 rtas_disable_msi(pdev);
133}
134
Michael Ellerman3a51c0c2009-01-22 20:54:31 +0000135static int check_req(struct pci_dev *pdev, int nvec, char *prop_name)
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000136{
137 struct device_node *dn;
138 struct pci_dn *pdn;
139 const u32 *req_msi;
140
141 pdn = get_pdn(pdev);
142 if (!pdn)
143 return -ENODEV;
144
145 dn = pdn->node;
146
Michael Ellerman3a51c0c2009-01-22 20:54:31 +0000147 req_msi = of_get_property(dn, prop_name, NULL);
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000148 if (!req_msi) {
Michael Ellerman3a51c0c2009-01-22 20:54:31 +0000149 pr_debug("rtas_msi: No %s on %s\n", prop_name, dn->full_name);
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000150 return -ENOENT;
151 }
152
153 if (*req_msi < nvec) {
Michael Ellerman3a51c0c2009-01-22 20:54:31 +0000154 pr_debug("rtas_msi: %s requests < %d MSIs\n", prop_name, nvec);
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000155 return -ENOSPC;
156 }
157
158 return 0;
159}
160
Michael Ellerman3a51c0c2009-01-22 20:54:31 +0000161static int check_req_msi(struct pci_dev *pdev, int nvec)
162{
163 return check_req(pdev, nvec, "ibm,req#msi");
164}
165
166static int check_req_msix(struct pci_dev *pdev, int nvec)
167{
168 return check_req(pdev, nvec, "ibm,req#msi-x");
169}
170
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000171static int rtas_msi_check_device(struct pci_dev *pdev, int nvec, int type)
172{
173 if (type == PCI_CAP_ID_MSIX)
Michael Ellerman3a51c0c2009-01-22 20:54:31 +0000174 return check_req_msix(pdev, nvec);
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000175
176 return check_req_msi(pdev, nvec);
177}
178
179static int rtas_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
180{
181 struct pci_dn *pdn;
182 int hwirq, virq, i, rc;
183 struct msi_desc *entry;
Michael Ellerman1db3e892007-10-23 14:23:44 +1000184 struct msi_msg msg;
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000185
186 pdn = get_pdn(pdev);
187 if (!pdn)
188 return -ENODEV;
189
190 /*
191 * Try the new more explicit firmware interface, if that fails fall
192 * back to the old interface. The old interface is known to never
193 * return MSI-Xs.
194 */
195 if (type == PCI_CAP_ID_MSI) {
196 rc = rtas_change_msi(pdn, RTAS_CHANGE_MSI_FN, nvec);
197
Michael Ellermand3853662007-09-20 16:36:50 +1000198 if (rc) {
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000199 pr_debug("rtas_msi: trying the old firmware call.\n");
200 rc = rtas_change_msi(pdn, RTAS_CHANGE_FN, nvec);
201 }
202 } else
203 rc = rtas_change_msi(pdn, RTAS_CHANGE_MSIX_FN, nvec);
204
Michael Ellermand3853662007-09-20 16:36:50 +1000205 if (rc) {
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000206 pr_debug("rtas_msi: rtas_change_msi() failed\n");
Michael Ellermanfcbe8092007-09-20 16:36:48 +1000207 return rc;
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000208 }
209
210 i = 0;
211 list_for_each_entry(entry, &pdev->msi_list, list) {
Michael Ellermane27ed692009-01-22 20:54:31 +0000212 hwirq = rtas_query_irq_number(pdn, i++);
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000213 if (hwirq < 0) {
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000214 pr_debug("rtas_msi: error (%d) getting hwirq\n", rc);
Michael Ellermanfcbe8092007-09-20 16:36:48 +1000215 return hwirq;
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000216 }
217
218 virq = irq_create_mapping(NULL, hwirq);
219
220 if (virq == NO_IRQ) {
221 pr_debug("rtas_msi: Failed mapping hwirq %d\n", hwirq);
Michael Ellermanfcbe8092007-09-20 16:36:48 +1000222 return -ENOSPC;
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000223 }
224
225 dev_dbg(&pdev->dev, "rtas_msi: allocated virq %d\n", virq);
226 set_irq_msi(virq, entry);
Michael Ellerman1db3e892007-10-23 14:23:44 +1000227
228 /* Read config space back so we can restore after reset */
229 read_msi_msg(virq, &msg);
230 entry->msg = msg;
231
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000232 unmask_msi_irq(virq);
233 }
234
235 return 0;
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000236}
237
238static void rtas_msi_pci_irq_fixup(struct pci_dev *pdev)
239{
240 /* No LSI -> leave MSIs (if any) configured */
241 if (pdev->irq == NO_IRQ) {
242 dev_dbg(&pdev->dev, "rtas_msi: no LSI, nothing to do.\n");
243 return;
244 }
245
246 /* No MSI -> MSIs can't have been assigned by fw, leave LSI */
Michael Ellerman649781f2009-01-22 20:54:32 +0000247 if (check_req_msi(pdev, 1) && check_req_msix(pdev, 1)) {
248 dev_dbg(&pdev->dev, "rtas_msi: no req#msi/x, nothing to do.\n");
Michael Ellerman85f2bf92007-05-08 12:58:35 +1000249 return;
250 }
251
252 dev_dbg(&pdev->dev, "rtas_msi: disabling existing MSI.\n");
253 rtas_disable_msi(pdev);
254}
255
256static int rtas_msi_init(void)
257{
258 query_token = rtas_token("ibm,query-interrupt-source-number");
259 change_token = rtas_token("ibm,change-msi");
260
261 if ((query_token == RTAS_UNKNOWN_SERVICE) ||
262 (change_token == RTAS_UNKNOWN_SERVICE)) {
263 pr_debug("rtas_msi: no RTAS tokens, no MSI support.\n");
264 return -1;
265 }
266
267 pr_debug("rtas_msi: Registering RTAS MSI callbacks.\n");
268
269 WARN_ON(ppc_md.setup_msi_irqs);
270 ppc_md.setup_msi_irqs = rtas_setup_msi_irqs;
271 ppc_md.teardown_msi_irqs = rtas_teardown_msi_irqs;
272 ppc_md.msi_check_device = rtas_msi_check_device;
273
274 WARN_ON(ppc_md.pci_irq_fixup);
275 ppc_md.pci_irq_fixup = rtas_msi_pci_irq_fixup;
276
277 return 0;
278}
279arch_initcall(rtas_msi_init);