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