1 /*
2 * Adding PCI-E MSI support for PPC4XX SoCs.
3 *
4 * Copyright (c) 2010, Applied Micro Circuits Corporation
5 * Authors: Tirumala R Marri <tmarri@apm.com>
6 * Feng Kan <fkan@apm.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21 * MA 02111-1307 USA
22 */
23
24 #include <linux/irq.h>
25 #include <linux/pci.h>
26 #include <linux/msi.h>
27 #include <linux/of_platform.h>
28 #include <linux/interrupt.h>
29 #include <linux/export.h>
30 #include <linux/kernel.h>
31 #include <asm/prom.h>
32 #include <asm/hw_irq.h>
33 #include <asm/ppc-pci.h>
34 #include <asm/dcr.h>
35 #include <asm/dcr-regs.h>
36 #include <asm/msi_bitmap.h>
37
38 #define PEIH_TERMADH 0x00
39 #define PEIH_TERMADL 0x08
40 #define PEIH_MSIED 0x10
41 #define PEIH_MSIMK 0x18
42 #define PEIH_MSIASS 0x20
43 #define PEIH_FLUSH0 0x30
44 #define PEIH_FLUSH1 0x38
45 #define PEIH_CNTRST 0x48
46
47 static int msi_irqs;
48
49 struct ppc4xx_msi {
50 u32 msi_addr_lo;
51 u32 msi_addr_hi;
52 void __iomem *msi_regs;
53 int *msi_virqs;
54 struct msi_bitmap bitmap;
55 struct device_node *msi_dev;
56 };
57
58 static struct ppc4xx_msi ppc4xx_msi;
59
ppc4xx_msi_init_allocator(struct platform_device * dev,struct ppc4xx_msi * msi_data)60 static int ppc4xx_msi_init_allocator(struct platform_device *dev,
61 struct ppc4xx_msi *msi_data)
62 {
63 int err;
64
65 err = msi_bitmap_alloc(&msi_data->bitmap, msi_irqs,
66 dev->dev.of_node);
67 if (err)
68 return err;
69
70 err = msi_bitmap_reserve_dt_hwirqs(&msi_data->bitmap);
71 if (err < 0) {
72 msi_bitmap_free(&msi_data->bitmap);
73 return err;
74 }
75
76 return 0;
77 }
78
ppc4xx_setup_msi_irqs(struct pci_dev * dev,int nvec,int type)79 static int ppc4xx_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
80 {
81 int int_no = -ENOMEM;
82 unsigned int virq;
83 struct msi_msg msg;
84 struct msi_desc *entry;
85 struct ppc4xx_msi *msi_data = &ppc4xx_msi;
86
87 dev_dbg(&dev->dev, "PCIE-MSI:%s called. vec %x type %d\n",
88 __func__, nvec, type);
89 if (type == PCI_CAP_ID_MSIX)
90 pr_debug("ppc4xx msi: MSI-X untested, trying anyway.\n");
91
92 msi_data->msi_virqs = kmalloc((msi_irqs) * sizeof(int), GFP_KERNEL);
93 if (!msi_data->msi_virqs)
94 return -ENOMEM;
95
96 for_each_pci_msi_entry(entry, dev) {
97 int_no = msi_bitmap_alloc_hwirqs(&msi_data->bitmap, 1);
98 if (int_no >= 0)
99 break;
100 if (int_no < 0) {
101 pr_debug("%s: fail allocating msi interrupt\n",
102 __func__);
103 }
104 virq = irq_of_parse_and_map(msi_data->msi_dev, int_no);
105 if (!virq) {
106 dev_err(&dev->dev, "%s: fail mapping irq\n", __func__);
107 msi_bitmap_free_hwirqs(&msi_data->bitmap, int_no, 1);
108 return -ENOSPC;
109 }
110 dev_dbg(&dev->dev, "%s: virq = %d\n", __func__, virq);
111
112 /* Setup msi address space */
113 msg.address_hi = msi_data->msi_addr_hi;
114 msg.address_lo = msi_data->msi_addr_lo;
115
116 irq_set_msi_desc(virq, entry);
117 msg.data = int_no;
118 pci_write_msi_msg(virq, &msg);
119 }
120 return 0;
121 }
122
ppc4xx_teardown_msi_irqs(struct pci_dev * dev)123 void ppc4xx_teardown_msi_irqs(struct pci_dev *dev)
124 {
125 struct msi_desc *entry;
126 struct ppc4xx_msi *msi_data = &ppc4xx_msi;
127 irq_hw_number_t hwirq;
128
129 dev_dbg(&dev->dev, "PCIE-MSI: tearing down msi irqs\n");
130
131 for_each_pci_msi_entry(entry, dev) {
132 if (!entry->irq)
133 continue;
134 hwirq = virq_to_hw(entry->irq);
135 irq_set_msi_desc(entry->irq, NULL);
136 irq_dispose_mapping(entry->irq);
137 msi_bitmap_free_hwirqs(&msi_data->bitmap, hwirq, 1);
138 }
139 }
140
ppc4xx_setup_pcieh_hw(struct platform_device * dev,struct resource res,struct ppc4xx_msi * msi)141 static int ppc4xx_setup_pcieh_hw(struct platform_device *dev,
142 struct resource res, struct ppc4xx_msi *msi)
143 {
144 const u32 *msi_data;
145 const u32 *msi_mask;
146 const u32 *sdr_addr;
147 dma_addr_t msi_phys;
148 void *msi_virt;
149
150 sdr_addr = of_get_property(dev->dev.of_node, "sdr-base", NULL);
151 if (!sdr_addr)
152 return -1;
153
154 mtdcri(SDR0, *sdr_addr, upper_32_bits(res.start)); /*HIGH addr */
155 mtdcri(SDR0, *sdr_addr + 1, lower_32_bits(res.start)); /* Low addr */
156
157 msi->msi_dev = of_find_node_by_name(NULL, "ppc4xx-msi");
158 if (!msi->msi_dev)
159 return -ENODEV;
160
161 msi->msi_regs = of_iomap(msi->msi_dev, 0);
162 if (!msi->msi_regs) {
163 dev_err(&dev->dev, "of_iomap problem failed\n");
164 return -ENOMEM;
165 }
166 dev_dbg(&dev->dev, "PCIE-MSI: msi register mapped 0x%x 0x%x\n",
167 (u32) (msi->msi_regs + PEIH_TERMADH), (u32) (msi->msi_regs));
168
169 msi_virt = dma_alloc_coherent(&dev->dev, 64, &msi_phys, GFP_KERNEL);
170 if (!msi_virt)
171 return -ENOMEM;
172 msi->msi_addr_hi = upper_32_bits(msi_phys);
173 msi->msi_addr_lo = lower_32_bits(msi_phys & 0xffffffff);
174 dev_dbg(&dev->dev, "PCIE-MSI: msi address high 0x%x, low 0x%x\n",
175 msi->msi_addr_hi, msi->msi_addr_lo);
176
177 /* Progam the Interrupt handler Termination addr registers */
178 out_be32(msi->msi_regs + PEIH_TERMADH, msi->msi_addr_hi);
179 out_be32(msi->msi_regs + PEIH_TERMADL, msi->msi_addr_lo);
180
181 msi_data = of_get_property(dev->dev.of_node, "msi-data", NULL);
182 if (!msi_data)
183 return -1;
184 msi_mask = of_get_property(dev->dev.of_node, "msi-mask", NULL);
185 if (!msi_mask)
186 return -1;
187 /* Program MSI Expected data and Mask bits */
188 out_be32(msi->msi_regs + PEIH_MSIED, *msi_data);
189 out_be32(msi->msi_regs + PEIH_MSIMK, *msi_mask);
190
191 dma_free_coherent(&dev->dev, 64, msi_virt, msi_phys);
192
193 return 0;
194 }
195
ppc4xx_of_msi_remove(struct platform_device * dev)196 static int ppc4xx_of_msi_remove(struct platform_device *dev)
197 {
198 struct ppc4xx_msi *msi = dev->dev.platform_data;
199 int i;
200 int virq;
201
202 for (i = 0; i < msi_irqs; i++) {
203 virq = msi->msi_virqs[i];
204 if (virq)
205 irq_dispose_mapping(virq);
206 }
207
208 if (msi->bitmap.bitmap)
209 msi_bitmap_free(&msi->bitmap);
210 iounmap(msi->msi_regs);
211 of_node_put(msi->msi_dev);
212 kfree(msi);
213
214 return 0;
215 }
216
ppc4xx_msi_probe(struct platform_device * dev)217 static int ppc4xx_msi_probe(struct platform_device *dev)
218 {
219 struct ppc4xx_msi *msi;
220 struct resource res;
221 int err = 0;
222 struct pci_controller *phb;
223
224 dev_dbg(&dev->dev, "PCIE-MSI: Setting up MSI support...\n");
225
226 msi = kzalloc(sizeof(struct ppc4xx_msi), GFP_KERNEL);
227 if (!msi) {
228 dev_err(&dev->dev, "No memory for MSI structure\n");
229 return -ENOMEM;
230 }
231 dev->dev.platform_data = msi;
232
233 /* Get MSI ranges */
234 err = of_address_to_resource(dev->dev.of_node, 0, &res);
235 if (err) {
236 dev_err(&dev->dev, "%s resource error!\n",
237 dev->dev.of_node->full_name);
238 goto error_out;
239 }
240
241 msi_irqs = of_irq_count(dev->dev.of_node);
242 if (!msi_irqs)
243 return -ENODEV;
244
245 if (ppc4xx_setup_pcieh_hw(dev, res, msi))
246 goto error_out;
247
248 err = ppc4xx_msi_init_allocator(dev, msi);
249 if (err) {
250 dev_err(&dev->dev, "Error allocating MSI bitmap\n");
251 goto error_out;
252 }
253 ppc4xx_msi = *msi;
254
255 list_for_each_entry(phb, &hose_list, list_node) {
256 phb->controller_ops.setup_msi_irqs = ppc4xx_setup_msi_irqs;
257 phb->controller_ops.teardown_msi_irqs = ppc4xx_teardown_msi_irqs;
258 }
259 return err;
260
261 error_out:
262 ppc4xx_of_msi_remove(dev);
263 return err;
264 }
265 static const struct of_device_id ppc4xx_msi_ids[] = {
266 {
267 .compatible = "amcc,ppc4xx-msi",
268 },
269 {}
270 };
271 static struct platform_driver ppc4xx_msi_driver = {
272 .probe = ppc4xx_msi_probe,
273 .remove = ppc4xx_of_msi_remove,
274 .driver = {
275 .name = "ppc4xx-msi",
276 .of_match_table = ppc4xx_msi_ids,
277 },
278
279 };
280
ppc4xx_msi_init(void)281 static __init int ppc4xx_msi_init(void)
282 {
283 return platform_driver_register(&ppc4xx_msi_driver);
284 }
285
286 subsys_initcall(ppc4xx_msi_init);
287