dm thin metadata: fix __udivdi3 undefined on 32-bit
[linux/fpc-iii.git] / drivers / base / platform-msi.c
blob5df4575b5ba765de181a02701c706a6802d38b13
1 /*
2 * MSI framework for platform devices
4 * Copyright (C) 2015 ARM Limited, All Rights Reserved.
5 * Author: Marc Zyngier <marc.zyngier@arm.com>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
20 #include <linux/device.h>
21 #include <linux/idr.h>
22 #include <linux/irq.h>
23 #include <linux/irqdomain.h>
24 #include <linux/msi.h>
25 #include <linux/slab.h>
27 #define DEV_ID_SHIFT 24
30 * Internal data structure containing a (made up, but unique) devid
31 * and the callback to write the MSI message.
33 struct platform_msi_priv_data {
34 irq_write_msi_msg_t write_msg;
35 int devid;
38 /* The devid allocator */
39 static DEFINE_IDA(platform_msi_devid_ida);
41 #ifdef GENERIC_MSI_DOMAIN_OPS
43 * Convert an msi_desc to a globaly unique identifier (per-device
44 * devid + msi_desc position in the msi_list).
46 static irq_hw_number_t platform_msi_calc_hwirq(struct msi_desc *desc)
48 u32 devid;
50 devid = desc->platform.msi_priv_data->devid;
52 return (devid << (32 - DEV_ID_SHIFT)) | desc->platform.msi_index;
55 static void platform_msi_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
57 arg->desc = desc;
58 arg->hwirq = platform_msi_calc_hwirq(desc);
61 static int platform_msi_init(struct irq_domain *domain,
62 struct msi_domain_info *info,
63 unsigned int virq, irq_hw_number_t hwirq,
64 msi_alloc_info_t *arg)
66 return irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
67 info->chip, info->chip_data);
69 #else
70 #define platform_msi_set_desc NULL
71 #define platform_msi_init NULL
72 #endif
74 static void platform_msi_update_dom_ops(struct msi_domain_info *info)
76 struct msi_domain_ops *ops = info->ops;
78 BUG_ON(!ops);
80 if (ops->msi_init == NULL)
81 ops->msi_init = platform_msi_init;
82 if (ops->set_desc == NULL)
83 ops->set_desc = platform_msi_set_desc;
86 static void platform_msi_write_msg(struct irq_data *data, struct msi_msg *msg)
88 struct msi_desc *desc = irq_data_get_msi_desc(data);
89 struct platform_msi_priv_data *priv_data;
91 priv_data = desc->platform.msi_priv_data;
93 priv_data->write_msg(desc, msg);
96 static void platform_msi_update_chip_ops(struct msi_domain_info *info)
98 struct irq_chip *chip = info->chip;
100 BUG_ON(!chip);
101 if (!chip->irq_mask)
102 chip->irq_mask = irq_chip_mask_parent;
103 if (!chip->irq_unmask)
104 chip->irq_unmask = irq_chip_unmask_parent;
105 if (!chip->irq_eoi)
106 chip->irq_eoi = irq_chip_eoi_parent;
107 if (!chip->irq_set_affinity)
108 chip->irq_set_affinity = msi_domain_set_affinity;
109 if (!chip->irq_write_msi_msg)
110 chip->irq_write_msi_msg = platform_msi_write_msg;
113 static void platform_msi_free_descs(struct device *dev)
115 struct msi_desc *desc, *tmp;
117 list_for_each_entry_safe(desc, tmp, dev_to_msi_list(dev), list) {
118 list_del(&desc->list);
119 free_msi_entry(desc);
123 static int platform_msi_alloc_descs(struct device *dev, int nvec,
124 struct platform_msi_priv_data *data)
127 int i;
129 for (i = 0; i < nvec; i++) {
130 struct msi_desc *desc;
132 desc = alloc_msi_entry(dev);
133 if (!desc)
134 break;
136 desc->platform.msi_priv_data = data;
137 desc->platform.msi_index = i;
138 desc->nvec_used = 1;
140 list_add_tail(&desc->list, dev_to_msi_list(dev));
143 if (i != nvec) {
144 /* Clean up the mess */
145 platform_msi_free_descs(dev);
147 return -ENOMEM;
150 return 0;
154 * platform_msi_create_irq_domain - Create a platform MSI interrupt domain
155 * @fwnode: Optional fwnode of the interrupt controller
156 * @info: MSI domain info
157 * @parent: Parent irq domain
159 * Updates the domain and chip ops and creates a platform MSI
160 * interrupt domain.
162 * Returns:
163 * A domain pointer or NULL in case of failure.
165 struct irq_domain *platform_msi_create_irq_domain(struct fwnode_handle *fwnode,
166 struct msi_domain_info *info,
167 struct irq_domain *parent)
169 struct irq_domain *domain;
171 if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
172 platform_msi_update_dom_ops(info);
173 if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
174 platform_msi_update_chip_ops(info);
176 domain = msi_create_irq_domain(fwnode, info, parent);
177 if (domain)
178 domain->bus_token = DOMAIN_BUS_PLATFORM_MSI;
180 return domain;
184 * platform_msi_domain_alloc_irqs - Allocate MSI interrupts for @dev
185 * @dev: The device for which to allocate interrupts
186 * @nvec: The number of interrupts to allocate
187 * @write_msi_msg: Callback to write an interrupt message for @dev
189 * Returns:
190 * Zero for success, or an error code in case of failure
192 int platform_msi_domain_alloc_irqs(struct device *dev, unsigned int nvec,
193 irq_write_msi_msg_t write_msi_msg)
195 struct platform_msi_priv_data *priv_data;
196 int err;
199 * Limit the number of interrupts to 256 per device. Should we
200 * need to bump this up, DEV_ID_SHIFT should be adjusted
201 * accordingly (which would impact the max number of MSI
202 * capable devices).
204 if (!dev->msi_domain || !write_msi_msg || !nvec ||
205 nvec > (1 << (32 - DEV_ID_SHIFT)))
206 return -EINVAL;
208 if (dev->msi_domain->bus_token != DOMAIN_BUS_PLATFORM_MSI) {
209 dev_err(dev, "Incompatible msi_domain, giving up\n");
210 return -EINVAL;
213 /* Already had a helping of MSI? Greed... */
214 if (!list_empty(dev_to_msi_list(dev)))
215 return -EBUSY;
217 priv_data = kzalloc(sizeof(*priv_data), GFP_KERNEL);
218 if (!priv_data)
219 return -ENOMEM;
221 priv_data->devid = ida_simple_get(&platform_msi_devid_ida,
222 0, 1 << DEV_ID_SHIFT, GFP_KERNEL);
223 if (priv_data->devid < 0) {
224 err = priv_data->devid;
225 goto out_free_data;
228 priv_data->write_msg = write_msi_msg;
230 err = platform_msi_alloc_descs(dev, nvec, priv_data);
231 if (err)
232 goto out_free_id;
234 err = msi_domain_alloc_irqs(dev->msi_domain, dev, nvec);
235 if (err)
236 goto out_free_desc;
238 return 0;
240 out_free_desc:
241 platform_msi_free_descs(dev);
242 out_free_id:
243 ida_simple_remove(&platform_msi_devid_ida, priv_data->devid);
244 out_free_data:
245 kfree(priv_data);
247 return err;
251 * platform_msi_domain_free_irqs - Free MSI interrupts for @dev
252 * @dev: The device for which to free interrupts
254 void platform_msi_domain_free_irqs(struct device *dev)
256 struct msi_desc *desc;
258 desc = first_msi_entry(dev);
259 if (desc) {
260 struct platform_msi_priv_data *data;
262 data = desc->platform.msi_priv_data;
264 ida_simple_remove(&platform_msi_devid_ida, data->devid);
265 kfree(data);
268 msi_domain_free_irqs(dev->msi_domain, dev);
269 platform_msi_free_descs(dev);