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/bootmem.h>
26 #include <linux/pci.h>
27 #include <linux/msi.h>
28 #include <linux/of_platform.h>
29 #include <linux/interrupt.h>
30 #include <linux/export.h>
31 #include <asm/prom.h>
32 #include <asm/hw_irq.h>
33 #include <asm/ppc-pci.h>
34 #include <boot/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 #define NR_MSI_IRQS 4
47
48 struct ppc4xx_msi {
49 u32 msi_addr_lo;
50 u32 msi_addr_hi;
51 void __iomem *msi_regs;
52 int msi_virqs[NR_MSI_IRQS];
53 struct msi_bitmap bitmap;
54 struct device_node *msi_dev;
55 };
56
57 static struct ppc4xx_msi ppc4xx_msi;
58
ppc4xx_msi_init_allocator(struct platform_device * dev,struct ppc4xx_msi * msi_data)59 static int ppc4xx_msi_init_allocator(struct platform_device *dev,
60 struct ppc4xx_msi *msi_data)
61 {
62 int err;
63
64 err = msi_bitmap_alloc(&msi_data->bitmap, NR_MSI_IRQS,
65 dev->dev.of_node);
66 if (err)
67 return err;
68
69 err = msi_bitmap_reserve_dt_hwirqs(&msi_data->bitmap);
70 if (err < 0) {
71 msi_bitmap_free(&msi_data->bitmap);
72 return err;
73 }
74
75 return 0;
76 }
77
ppc4xx_setup_msi_irqs(struct pci_dev * dev,int nvec,int type)78 static int ppc4xx_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
79 {
80 int int_no = -ENOMEM;
81 unsigned int virq;
82 struct msi_msg msg;
83 struct msi_desc *entry;
84 struct ppc4xx_msi *msi_data = &ppc4xx_msi;
85
86 list_for_each_entry(entry, &dev->msi_list, list) {
87 int_no = msi_bitmap_alloc_hwirqs(&msi_data->bitmap, 1);
88 if (int_no >= 0)
89 break;
90 if (int_no < 0) {
91 pr_debug("%s: fail allocating msi interrupt\n",
92 __func__);
93 }
94 virq = irq_of_parse_and_map(msi_data->msi_dev, int_no);
95 if (virq == NO_IRQ) {
96 dev_err(&dev->dev, "%s: fail mapping irq\n", __func__);
97 msi_bitmap_free_hwirqs(&msi_data->bitmap, int_no, 1);
98 return -ENOSPC;
99 }
100 dev_dbg(&dev->dev, "%s: virq = %d\n", __func__, virq);
101
102 /* Setup msi address space */
103 msg.address_hi = msi_data->msi_addr_hi;
104 msg.address_lo = msi_data->msi_addr_lo;
105
106 irq_set_msi_desc(virq, entry);
107 msg.data = int_no;
108 write_msi_msg(virq, &msg);
109 }
110 return 0;
111 }
112
ppc4xx_teardown_msi_irqs(struct pci_dev * dev)113 void ppc4xx_teardown_msi_irqs(struct pci_dev *dev)
114 {
115 struct msi_desc *entry;
116 struct ppc4xx_msi *msi_data = &ppc4xx_msi;
117
118 dev_dbg(&dev->dev, "PCIE-MSI: tearing down msi irqs\n");
119
120 list_for_each_entry(entry, &dev->msi_list, list) {
121 if (entry->irq == NO_IRQ)
122 continue;
123 irq_set_msi_desc(entry->irq, NULL);
124 msi_bitmap_free_hwirqs(&msi_data->bitmap,
125 virq_to_hw(entry->irq), 1);
126 irq_dispose_mapping(entry->irq);
127 }
128 }
129
ppc4xx_msi_check_device(struct pci_dev * pdev,int nvec,int type)130 static int ppc4xx_msi_check_device(struct pci_dev *pdev, int nvec, int type)
131 {
132 dev_dbg(&pdev->dev, "PCIE-MSI:%s called. vec %x type %d\n",
133 __func__, nvec, type);
134 if (type == PCI_CAP_ID_MSIX)
135 pr_debug("ppc4xx msi: MSI-X untested, trying anyway.\n");
136
137 return 0;
138 }
139
ppc4xx_setup_pcieh_hw(struct platform_device * dev,struct resource res,struct ppc4xx_msi * msi)140 static int ppc4xx_setup_pcieh_hw(struct platform_device *dev,
141 struct resource res, struct ppc4xx_msi *msi)
142 {
143 const u32 *msi_data;
144 const u32 *msi_mask;
145 const u32 *sdr_addr;
146 dma_addr_t msi_phys;
147 void *msi_virt;
148
149 sdr_addr = of_get_property(dev->dev.of_node, "sdr-base", NULL);
150 if (!sdr_addr)
151 return -1;
152
153 SDR0_WRITE(sdr_addr, (u64)res.start >> 32); /*HIGH addr */
154 SDR0_WRITE(sdr_addr + 1, res.start & 0xFFFFFFFF); /* Low addr */
155
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 msi->msi_addr_hi = 0x0;
171 msi->msi_addr_lo = (u32) msi_phys;
172 dev_dbg(&dev->dev, "PCIE-MSI: msi address 0x%x\n", msi->msi_addr_lo);
173
174 /* Progam the Interrupt handler Termination addr registers */
175 out_be32(msi->msi_regs + PEIH_TERMADH, msi->msi_addr_hi);
176 out_be32(msi->msi_regs + PEIH_TERMADL, msi->msi_addr_lo);
177
178 msi_data = of_get_property(dev->dev.of_node, "msi-data", NULL);
179 if (!msi_data)
180 return -1;
181 msi_mask = of_get_property(dev->dev.of_node, "msi-mask", NULL);
182 if (!msi_mask)
183 return -1;
184 /* Program MSI Expected data and Mask bits */
185 out_be32(msi->msi_regs + PEIH_MSIED, *msi_data);
186 out_be32(msi->msi_regs + PEIH_MSIMK, *msi_mask);
187
188 return 0;
189 }
190
ppc4xx_of_msi_remove(struct platform_device * dev)191 static int ppc4xx_of_msi_remove(struct platform_device *dev)
192 {
193 struct ppc4xx_msi *msi = dev->dev.platform_data;
194 int i;
195 int virq;
196
197 for (i = 0; i < NR_MSI_IRQS; i++) {
198 virq = msi->msi_virqs[i];
199 if (virq != NO_IRQ)
200 irq_dispose_mapping(virq);
201 }
202
203 if (msi->bitmap.bitmap)
204 msi_bitmap_free(&msi->bitmap);
205 iounmap(msi->msi_regs);
206 of_node_put(msi->msi_dev);
207 kfree(msi);
208
209 return 0;
210 }
211
ppc4xx_msi_probe(struct platform_device * dev)212 static int __devinit ppc4xx_msi_probe(struct platform_device *dev)
213 {
214 struct ppc4xx_msi *msi;
215 struct resource res;
216 int err = 0;
217
218 msi = &ppc4xx_msi;/*keep the msi data for further use*/
219
220 dev_dbg(&dev->dev, "PCIE-MSI: Setting up MSI support...\n");
221
222 msi = kzalloc(sizeof(struct ppc4xx_msi), GFP_KERNEL);
223 if (!msi) {
224 dev_err(&dev->dev, "No memory for MSI structure\n");
225 return -ENOMEM;
226 }
227 dev->dev.platform_data = msi;
228
229 /* Get MSI ranges */
230 err = of_address_to_resource(dev->dev.of_node, 0, &res);
231 if (err) {
232 dev_err(&dev->dev, "%s resource error!\n",
233 dev->dev.of_node->full_name);
234 goto error_out;
235 }
236
237 if (ppc4xx_setup_pcieh_hw(dev, res, msi))
238 goto error_out;
239
240 err = ppc4xx_msi_init_allocator(dev, msi);
241 if (err) {
242 dev_err(&dev->dev, "Error allocating MSI bitmap\n");
243 goto error_out;
244 }
245
246 ppc_md.setup_msi_irqs = ppc4xx_setup_msi_irqs;
247 ppc_md.teardown_msi_irqs = ppc4xx_teardown_msi_irqs;
248 ppc_md.msi_check_device = ppc4xx_msi_check_device;
249 return err;
250
251 error_out:
252 ppc4xx_of_msi_remove(dev);
253 return err;
254 }
255 static const struct of_device_id ppc4xx_msi_ids[] = {
256 {
257 .compatible = "amcc,ppc4xx-msi",
258 },
259 {}
260 };
261 static struct platform_driver ppc4xx_msi_driver = {
262 .probe = ppc4xx_msi_probe,
263 .remove = ppc4xx_of_msi_remove,
264 .driver = {
265 .name = "ppc4xx-msi",
266 .owner = THIS_MODULE,
267 .of_match_table = ppc4xx_msi_ids,
268 },
269
270 };
271
ppc4xx_msi_init(void)272 static __init int ppc4xx_msi_init(void)
273 {
274 return platform_driver_register(&ppc4xx_msi_driver);
275 }
276
277 subsys_initcall(ppc4xx_msi_init);
278