drivers/mailbox/qcom-ipcc.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
   4  */
   5
   6 #include <linux/bitfield.h>
   7 #include <linux/interrupt.h>
   8 #include <linux/irq.h>
   9 #include <linux/irqdomain.h>
  10 #include <linux/mailbox_controller.h>
  11 #include <linux/module.h>
  12 #include <linux/platform_device.h>
  13
  14 #include <dt-bindings/mailbox/qcom-ipcc.h>
  15
  16 /* IPCC Register offsets */
  17 #define IPCC_REG_SEND_ID                0x0c
  18 #define IPCC_REG_RECV_ID                0x10
  19 #define IPCC_REG_RECV_SIGNAL_ENABLE     0x14
  20 #define IPCC_REG_RECV_SIGNAL_DISABLE    0x18
  21 #define IPCC_REG_RECV_SIGNAL_CLEAR      0x1c
  22 #define IPCC_REG_CLIENT_CLEAR           0x38
  23
  24 #define IPCC_SIGNAL_ID_MASK             GENMASK(15, 0)
  25 #define IPCC_CLIENT_ID_MASK             GENMASK(31, 16)
  26
  27 #define IPCC_NO_PENDING_IRQ             GENMASK(31, 0)
  28
  29 /**
  30  * struct qcom_ipcc_chan_info - Per-mailbox-channel info
  31  * @client_id:  The client-id to which the interrupt has to be triggered
  32  * @signal_id:  The signal-id to which the interrupt has to be triggered
  33  */
  34 struct qcom_ipcc_chan_info {
  35         u16 client_id;
  36         u16 signal_id;
  37 };
  38
  39 /**
  40  * struct qcom_ipcc - Holder for the mailbox driver
  41  * @dev:                Device associated with this instance
  42  * @base:               Base address of the IPCC frame associated to APSS
  43  * @irq_domain:         The irq_domain associated with this instance
  44  * @chans:              The mailbox channels array
  45  * @mchan:              The per-mailbox channel info array
  46  * @mbox:               The mailbox controller
  47  * @num_chans:          Number of @chans elements
  48  * @irq:                Summary irq
  49  */
  50 struct qcom_ipcc {
  51         struct device *dev;
  52         void __iomem *base;
  53         struct irq_domain *irq_domain;
  54         struct mbox_chan *chans;
  55         struct qcom_ipcc_chan_info *mchan;
  56         struct mbox_controller mbox;
  57         int num_chans;
  58         int irq;
  59 };
  60
  61 static inline struct qcom_ipcc *to_qcom_ipcc(struct mbox_controller *mbox)
  62 {
  63         return container_of(mbox, struct qcom_ipcc, mbox);
  64 }
  65
  66 static inline u32 qcom_ipcc_get_hwirq(u16 client_id, u16 signal_id)
  67 {
  68         return FIELD_PREP(IPCC_CLIENT_ID_MASK, client_id) |
  69                FIELD_PREP(IPCC_SIGNAL_ID_MASK, signal_id);
  70 }
  71
  72 static irqreturn_t qcom_ipcc_irq_fn(int irq, void *data)
  73 {
  74         struct qcom_ipcc *ipcc = data;
  75         u32 hwirq;
  76         int virq;
  77
  78         for (;;) {
  79                 hwirq = readl(ipcc->base + IPCC_REG_RECV_ID);
  80                 if (hwirq == IPCC_NO_PENDING_IRQ)
  81                         break;
  82
  83                 virq = irq_find_mapping(ipcc->irq_domain, hwirq);
  84                 writel(hwirq, ipcc->base + IPCC_REG_RECV_SIGNAL_CLEAR);
  85                 generic_handle_irq(virq);
  86         }
  87
  88         return IRQ_HANDLED;
  89 }
  90
  91 static void qcom_ipcc_mask_irq(struct irq_data *irqd)
  92 {
  93         struct qcom_ipcc *ipcc = irq_data_get_irq_chip_data(irqd);
  94         irq_hw_number_t hwirq = irqd_to_hwirq(irqd);
  95
  96         writel(hwirq, ipcc->base + IPCC_REG_RECV_SIGNAL_DISABLE);
  97 }
  98
  99 static void qcom_ipcc_unmask_irq(struct irq_data *irqd)
 100 {
 101         struct qcom_ipcc *ipcc = irq_data_get_irq_chip_data(irqd);
 102         irq_hw_number_t hwirq = irqd_to_hwirq(irqd);
 103
 104         writel(hwirq, ipcc->base + IPCC_REG_RECV_SIGNAL_ENABLE);
 105 }
 106
 107 static struct irq_chip qcom_ipcc_irq_chip = {
 108         .name = "ipcc",
 109         .irq_mask = qcom_ipcc_mask_irq,
 110         .irq_unmask = qcom_ipcc_unmask_irq,
 111         .flags = IRQCHIP_SKIP_SET_WAKE,
 112 };
 113
 114 static int qcom_ipcc_domain_map(struct irq_domain *d, unsigned int irq,
 115                                 irq_hw_number_t hw)
 116 {
 117         struct qcom_ipcc *ipcc = d->host_data;
 118
 119         irq_set_chip_and_handler(irq, &qcom_ipcc_irq_chip, handle_level_irq);
 120         irq_set_chip_data(irq, ipcc);
 121         irq_set_noprobe(irq);
 122
 123         return 0;
 124 }
 125
 126 static int qcom_ipcc_domain_xlate(struct irq_domain *d,
 127                                   struct device_node *node, const u32 *intspec,
 128                                   unsigned int intsize,
 129                                   unsigned long *out_hwirq,
 130                                   unsigned int *out_type)
 131 {
 132         if (intsize != 3)
 133                 return -EINVAL;
 134
 135         *out_hwirq = qcom_ipcc_get_hwirq(intspec[0], intspec[1]);
 136         *out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
 137
 138         return 0;
 139 }
 140
 141 static const struct irq_domain_ops qcom_ipcc_irq_ops = {
 142         .map = qcom_ipcc_domain_map,
 143         .xlate = qcom_ipcc_domain_xlate,
 144 };
 145
 146 static int qcom_ipcc_mbox_send_data(struct mbox_chan *chan, void *data)
 147 {
 148         struct qcom_ipcc *ipcc = to_qcom_ipcc(chan->mbox);
 149         struct qcom_ipcc_chan_info *mchan = chan->con_priv;
 150         u32 hwirq;
 151
 152         hwirq = qcom_ipcc_get_hwirq(mchan->client_id, mchan->signal_id);
 153         writel(hwirq, ipcc->base + IPCC_REG_SEND_ID);
 154
 155         return 0;
 156 }
 157
 158 static void qcom_ipcc_mbox_shutdown(struct mbox_chan *chan)
 159 {
 160         chan->con_priv = NULL;
 161 }
 162
 163 static struct mbox_chan *qcom_ipcc_mbox_xlate(struct mbox_controller *mbox,
 164                                         const struct of_phandle_args *ph)
 165 {
 166         struct qcom_ipcc *ipcc = to_qcom_ipcc(mbox);
 167         struct qcom_ipcc_chan_info *mchan;
 168         struct mbox_chan *chan;
 169         struct device *dev;
 170         int chan_id;
 171
 172         dev = ipcc->dev;
 173
 174         if (ph->args_count != 2)
 175                 return ERR_PTR(-EINVAL);
 176
 177         for (chan_id = 0; chan_id < mbox->num_chans; chan_id++) {
 178                 chan = &ipcc->chans[chan_id];
 179                 mchan = chan->con_priv;
 180
 181                 if (!mchan)
 182                         break;
 183                 else if (mchan->client_id == ph->args[0] &&
 184                                 mchan->signal_id == ph->args[1])
 185                         return ERR_PTR(-EBUSY);
 186         }
 187
 188         if (chan_id >= mbox->num_chans)
 189                 return ERR_PTR(-EBUSY);
 190
 191         mchan = devm_kzalloc(dev, sizeof(*mchan), GFP_KERNEL);
 192         if (!mchan)
 193                 return ERR_PTR(-ENOMEM);
 194
 195         mchan->client_id = ph->args[0];
 196         mchan->signal_id = ph->args[1];
 197         chan->con_priv = mchan;
 198
 199         return chan;
 200 }
 201
 202 static const struct mbox_chan_ops ipcc_mbox_chan_ops = {
 203         .send_data = qcom_ipcc_mbox_send_data,
 204         .shutdown = qcom_ipcc_mbox_shutdown,
 205 };
 206
 207 static int qcom_ipcc_setup_mbox(struct qcom_ipcc *ipcc,
 208                                 struct device_node *controller_dn)
 209 {
 210         struct of_phandle_args curr_ph;
 211         struct device_node *client_dn;
 212         struct mbox_controller *mbox;
 213         struct device *dev = ipcc->dev;
 214         int i, j, ret;
 215
 216         /*
 217          * Find out the number of clients interested in this mailbox
 218          * and create channels accordingly.
 219          */
 220         ipcc->num_chans = 0;
 221         for_each_node_with_property(client_dn, "mboxes") {
 222                 if (!of_device_is_available(client_dn))
 223                         continue;
 224                 i = of_count_phandle_with_args(client_dn,
 225                                                 "mboxes", "#mbox-cells");
 226                 for (j = 0; j < i; j++) {
 227                         ret = of_parse_phandle_with_args(client_dn, "mboxes",
 228                                                 "#mbox-cells", j, &curr_ph);
 229                         of_node_put(curr_ph.np);
 230                         if (!ret && curr_ph.np == controller_dn)
 231                                 ipcc->num_chans++;
 232                 }
 233         }
 234
 235         /* If no clients are found, skip registering as a mbox controller */
 236         if (!ipcc->num_chans)
 237                 return 0;
 238
 239         ipcc->chans = devm_kcalloc(dev, ipcc->num_chans,
 240                                         sizeof(struct mbox_chan), GFP_KERNEL);
 241         if (!ipcc->chans)
 242                 return -ENOMEM;
 243
 244         mbox = &ipcc->mbox;
 245         mbox->dev = dev;
 246         mbox->num_chans = ipcc->num_chans;
 247         mbox->chans = ipcc->chans;
 248         mbox->ops = &ipcc_mbox_chan_ops;
 249         mbox->of_xlate = qcom_ipcc_mbox_xlate;
 250         mbox->txdone_irq = false;
 251         mbox->txdone_poll = false;
 252
 253         return devm_mbox_controller_register(dev, mbox);
 254 }
 255
 256 static int qcom_ipcc_pm_resume(struct device *dev)
 257 {
 258         struct qcom_ipcc *ipcc = dev_get_drvdata(dev);
 259         u32 hwirq;
 260         int virq;
 261
 262         hwirq = readl(ipcc->base + IPCC_REG_RECV_ID);
 263         if (hwirq == IPCC_NO_PENDING_IRQ)
 264                 return 0;
 265
 266         virq = irq_find_mapping(ipcc->irq_domain, hwirq);
 267
 268         dev_dbg(dev, "virq: %d triggered client-id: %ld; signal-id: %ld\n", virq,
 269                 FIELD_GET(IPCC_CLIENT_ID_MASK, hwirq), FIELD_GET(IPCC_SIGNAL_ID_MASK, hwirq));
 270
 271         return 0;
 272 }
 273
 274 static int qcom_ipcc_probe(struct platform_device *pdev)
 275 {
 276         struct qcom_ipcc *ipcc;
 277         static int id;
 278         char *name;
 279         int ret;
 280
 281         ipcc = devm_kzalloc(&pdev->dev, sizeof(*ipcc), GFP_KERNEL);
 282         if (!ipcc)
 283                 return -ENOMEM;
 284
 285         ipcc->dev = &pdev->dev;
 286
 287         ipcc->base = devm_platform_ioremap_resource(pdev, 0);
 288         if (IS_ERR(ipcc->base))
 289                 return PTR_ERR(ipcc->base);
 290
 291         ipcc->irq = platform_get_irq(pdev, 0);
 292         if (ipcc->irq < 0)
 293                 return ipcc->irq;
 294
 295         name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "ipcc_%d", id++);
 296         if (!name)
 297                 return -ENOMEM;
 298
 299         ipcc->irq_domain = irq_domain_add_tree(pdev->dev.of_node,
 300                                                &qcom_ipcc_irq_ops, ipcc);
 301         if (!ipcc->irq_domain)
 302                 return -ENOMEM;
 303
 304         ret = qcom_ipcc_setup_mbox(ipcc, pdev->dev.of_node);
 305         if (ret)
 306                 goto err_mbox;
 307
 308         ret = devm_request_irq(&pdev->dev, ipcc->irq, qcom_ipcc_irq_fn,
 309                                IRQF_TRIGGER_HIGH | IRQF_NO_SUSPEND |
 310                                IRQF_NO_THREAD, name, ipcc);
 311         if (ret < 0) {
 312                 dev_err(&pdev->dev, "Failed to register the irq: %d\n", ret);
 313                 goto err_req_irq;
 314         }
 315
 316         platform_set_drvdata(pdev, ipcc);
 317
 318         return 0;
 319
 320 err_req_irq:
 321         if (ipcc->num_chans)
 322                 mbox_controller_unregister(&ipcc->mbox);
 323 err_mbox:
 324         irq_domain_remove(ipcc->irq_domain);
 325
 326         return ret;
 327 }
 328
 329 static void qcom_ipcc_remove(struct platform_device *pdev)
 330 {
 331         struct qcom_ipcc *ipcc = platform_get_drvdata(pdev);
 332
 333         disable_irq_wake(ipcc->irq);
 334         irq_domain_remove(ipcc->irq_domain);
 335 }
 336
 337 static const struct of_device_id qcom_ipcc_of_match[] = {
 338         { .compatible = "qcom,ipcc"},
 339         {}
 340 };
 341 MODULE_DEVICE_TABLE(of, qcom_ipcc_of_match);
 342
 343 static const struct dev_pm_ops qcom_ipcc_dev_pm_ops = {
 344         NOIRQ_SYSTEM_SLEEP_PM_OPS(NULL, qcom_ipcc_pm_resume)
 345 };
 346
 347 static struct platform_driver qcom_ipcc_driver = {
 348         .probe = qcom_ipcc_probe,
 349         .remove = qcom_ipcc_remove,
 350         .driver = {
 351                 .name = "qcom-ipcc",
 352                 .of_match_table = qcom_ipcc_of_match,
 353                 .suppress_bind_attrs = true,
 354                 .pm = pm_sleep_ptr(&qcom_ipcc_dev_pm_ops),
 355         },
 356 };
 357
 358 static int __init qcom_ipcc_init(void)
 359 {
 360         return platform_driver_register(&qcom_ipcc_driver);
 361 }
 362 arch_initcall(qcom_ipcc_init);
 363
 364 MODULE_AUTHOR("Venkata Narendra Kumar Gutta <vnkgutta@codeaurora.org>");
 365 MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
 366 MODULE_DESCRIPTION("Qualcomm Technologies, Inc. IPCC driver");
 367 MODULE_LICENSE("GPL v2");