1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Freescale Management Complex (MC) bus driver MSI support
4 *
5 * Copyright (C) 2015-2016 Freescale Semiconductor, Inc.
6 * Author: German Rivera <German.Rivera@freescale.com>
7 *
8 */
9
10 #include <linux/of_device.h>
11 #include <linux/of_address.h>
12 #include <linux/of_irq.h>
13 #include <linux/irq.h>
14 #include <linux/irqdomain.h>
15 #include <linux/msi.h>
16 #include <linux/acpi_iort.h>
17
18 #include "fsl-mc-private.h"
19
20 #ifdef GENERIC_MSI_DOMAIN_OPS
21 /*
22 * Generate a unique ID identifying the interrupt (only used within the MSI
23 * irqdomain. Combine the icid with the interrupt index.
24 */
fsl_mc_domain_calc_hwirq(struct fsl_mc_device * dev,struct msi_desc * desc)25 static irq_hw_number_t fsl_mc_domain_calc_hwirq(struct fsl_mc_device *dev,
26 struct msi_desc *desc)
27 {
28 /*
29 * Make the base hwirq value for ICID*10000 so it is readable
30 * as a decimal value in /proc/interrupts.
31 */
32 return (irq_hw_number_t)(desc->msi_index + (dev->icid * 10000));
33 }
34
fsl_mc_msi_set_desc(msi_alloc_info_t * arg,struct msi_desc * desc)35 static void fsl_mc_msi_set_desc(msi_alloc_info_t *arg,
36 struct msi_desc *desc)
37 {
38 arg->desc = desc;
39 arg->hwirq = fsl_mc_domain_calc_hwirq(to_fsl_mc_device(desc->dev),
40 desc);
41 }
42 #else
43 #define fsl_mc_msi_set_desc NULL
44 #endif
45
fsl_mc_msi_update_dom_ops(struct msi_domain_info * info)46 static void fsl_mc_msi_update_dom_ops(struct msi_domain_info *info)
47 {
48 struct msi_domain_ops *ops = info->ops;
49
50 if (!ops)
51 return;
52
53 /*
54 * set_desc should not be set by the caller
55 */
56 if (!ops->set_desc)
57 ops->set_desc = fsl_mc_msi_set_desc;
58 }
59
__fsl_mc_msi_write_msg(struct fsl_mc_device * mc_bus_dev,struct fsl_mc_device_irq * mc_dev_irq,struct msi_desc * msi_desc)60 static void __fsl_mc_msi_write_msg(struct fsl_mc_device *mc_bus_dev,
61 struct fsl_mc_device_irq *mc_dev_irq,
62 struct msi_desc *msi_desc)
63 {
64 int error;
65 struct fsl_mc_device *owner_mc_dev = mc_dev_irq->mc_dev;
66 struct dprc_irq_cfg irq_cfg;
67
68 /*
69 * msi_desc->msg.address is 0x0 when this function is invoked in
70 * the free_irq() code path. In this case, for the MC, we don't
71 * really need to "unprogram" the MSI, so we just return.
72 */
73 if (msi_desc->msg.address_lo == 0x0 && msi_desc->msg.address_hi == 0x0)
74 return;
75
76 if (!owner_mc_dev)
77 return;
78
79 irq_cfg.paddr = ((u64)msi_desc->msg.address_hi << 32) |
80 msi_desc->msg.address_lo;
81 irq_cfg.val = msi_desc->msg.data;
82 irq_cfg.irq_num = msi_desc->irq;
83
84 if (owner_mc_dev == mc_bus_dev) {
85 /*
86 * IRQ is for the mc_bus_dev's DPRC itself
87 */
88 error = dprc_set_irq(mc_bus_dev->mc_io,
89 MC_CMD_FLAG_INTR_DIS | MC_CMD_FLAG_PRI,
90 mc_bus_dev->mc_handle,
91 mc_dev_irq->dev_irq_index,
92 &irq_cfg);
93 if (error < 0) {
94 dev_err(&owner_mc_dev->dev,
95 "dprc_set_irq() failed: %d\n", error);
96 }
97 } else {
98 /*
99 * IRQ is for for a child device of mc_bus_dev
100 */
101 error = dprc_set_obj_irq(mc_bus_dev->mc_io,
102 MC_CMD_FLAG_INTR_DIS | MC_CMD_FLAG_PRI,
103 mc_bus_dev->mc_handle,
104 owner_mc_dev->obj_desc.type,
105 owner_mc_dev->obj_desc.id,
106 mc_dev_irq->dev_irq_index,
107 &irq_cfg);
108 if (error < 0) {
109 dev_err(&owner_mc_dev->dev,
110 "dprc_obj_set_irq() failed: %d\n", error);
111 }
112 }
113 }
114
115 /*
116 * NOTE: This function is invoked with interrupts disabled
117 */
fsl_mc_msi_write_msg(struct irq_data * irq_data,struct msi_msg * msg)118 static void fsl_mc_msi_write_msg(struct irq_data *irq_data,
119 struct msi_msg *msg)
120 {
121 struct msi_desc *msi_desc = irq_data_get_msi_desc(irq_data);
122 struct fsl_mc_device *mc_bus_dev = to_fsl_mc_device(msi_desc->dev);
123 struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
124 struct fsl_mc_device_irq *mc_dev_irq =
125 &mc_bus->irq_resources[msi_desc->msi_index];
126
127 msi_desc->msg = *msg;
128
129 /*
130 * Program the MSI (paddr, value) pair in the device:
131 */
132 __fsl_mc_msi_write_msg(mc_bus_dev, mc_dev_irq, msi_desc);
133 }
134
fsl_mc_msi_update_chip_ops(struct msi_domain_info * info)135 static void fsl_mc_msi_update_chip_ops(struct msi_domain_info *info)
136 {
137 struct irq_chip *chip = info->chip;
138
139 if (!chip)
140 return;
141
142 /*
143 * irq_write_msi_msg should not be set by the caller
144 */
145 if (!chip->irq_write_msi_msg)
146 chip->irq_write_msi_msg = fsl_mc_msi_write_msg;
147 }
148
149 /**
150 * fsl_mc_msi_create_irq_domain - Create a fsl-mc MSI interrupt domain
151 * @fwnode: Optional firmware node of the interrupt controller
152 * @info: MSI domain info
153 * @parent: Parent irq domain
154 *
155 * Updates the domain and chip ops and creates a fsl-mc MSI
156 * interrupt domain.
157 *
158 * Returns:
159 * A domain pointer or NULL in case of failure.
160 */
fsl_mc_msi_create_irq_domain(struct fwnode_handle * fwnode,struct msi_domain_info * info,struct irq_domain * parent)161 struct irq_domain *fsl_mc_msi_create_irq_domain(struct fwnode_handle *fwnode,
162 struct msi_domain_info *info,
163 struct irq_domain *parent)
164 {
165 struct irq_domain *domain;
166
167 if (WARN_ON((info->flags & MSI_FLAG_LEVEL_CAPABLE)))
168 info->flags &= ~MSI_FLAG_LEVEL_CAPABLE;
169 if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
170 fsl_mc_msi_update_dom_ops(info);
171 if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
172 fsl_mc_msi_update_chip_ops(info);
173 info->flags |= MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS | MSI_FLAG_FREE_MSI_DESCS;
174
175 domain = msi_create_irq_domain(fwnode, info, parent);
176 if (domain)
177 irq_domain_update_bus_token(domain, DOMAIN_BUS_FSL_MC_MSI);
178
179 return domain;
180 }
181
fsl_mc_find_msi_domain(struct device * dev)182 struct irq_domain *fsl_mc_find_msi_domain(struct device *dev)
183 {
184 struct device *root_dprc_dev;
185 struct device *bus_dev;
186 struct irq_domain *msi_domain;
187 struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
188
189 fsl_mc_get_root_dprc(dev, &root_dprc_dev);
190 bus_dev = root_dprc_dev->parent;
191
192 if (bus_dev->of_node) {
193 msi_domain = of_msi_map_get_device_domain(dev,
194 mc_dev->icid,
195 DOMAIN_BUS_FSL_MC_MSI);
196
197 /*
198 * if the msi-map property is missing assume that all the
199 * child containers inherit the domain from the parent
200 */
201 if (!msi_domain)
202
203 msi_domain = of_msi_get_domain(bus_dev,
204 bus_dev->of_node,
205 DOMAIN_BUS_FSL_MC_MSI);
206 } else {
207 msi_domain = iort_get_device_domain(dev, mc_dev->icid,
208 DOMAIN_BUS_FSL_MC_MSI);
209 }
210
211 return msi_domain;
212 }
213
fsl_mc_msi_domain_alloc_irqs(struct device * dev,unsigned int irq_count)214 int fsl_mc_msi_domain_alloc_irqs(struct device *dev, unsigned int irq_count)
215 {
216 struct irq_domain *msi_domain;
217 int error;
218
219 msi_domain = dev_get_msi_domain(dev);
220 if (!msi_domain)
221 return -EINVAL;
222
223 error = msi_setup_device_data(dev);
224 if (error)
225 return error;
226
227 msi_lock_descs(dev);
228 if (msi_first_desc(dev, MSI_DESC_ALL))
229 error = -EINVAL;
230 msi_unlock_descs(dev);
231 if (error)
232 return error;
233
234 /*
235 * NOTE: Calling this function will trigger the invocation of the
236 * its_fsl_mc_msi_prepare() callback
237 */
238 error = msi_domain_alloc_irqs(msi_domain, dev, irq_count);
239
240 if (error)
241 dev_err(dev, "Failed to allocate IRQs\n");
242 return error;
243 }
244
fsl_mc_msi_domain_free_irqs(struct device * dev)245 void fsl_mc_msi_domain_free_irqs(struct device *dev)
246 {
247 struct irq_domain *msi_domain;
248
249 msi_domain = dev_get_msi_domain(dev);
250 if (!msi_domain)
251 return;
252
253 msi_domain_free_irqs(msi_domain, dev);
254 }
255