drivers/firmware/imx/imx-scu-irq.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright 2019 NXP
   4  *
   5  * Implementation of the SCU IRQ functions using MU.
   6  *
   7  */
   8
   9 #include <dt-bindings/firmware/imx/rsrc.h>
  10 #include <linux/firmware/imx/ipc.h>
  11 #include <linux/firmware/imx/sci.h>
  12 #include <linux/mailbox_client.h>
  13
  14 #define IMX_SC_IRQ_FUNC_ENABLE  1
  15 #define IMX_SC_IRQ_FUNC_STATUS  2
  16 #define IMX_SC_IRQ_NUM_GROUP    4
  17
  18 static u32 mu_resource_id;
  19
  20 struct imx_sc_msg_irq_get_status {
  21         struct imx_sc_rpc_msg hdr;
  22         union {
  23                 struct {
  24                         u16 resource;
  25                         u8 group;
  26                         u8 reserved;
  27                 } __packed req;
  28                 struct {
  29                         u32 status;
  30                 } resp;
  31         } data;
  32 };
  33
  34 struct imx_sc_msg_irq_enable {
  35         struct imx_sc_rpc_msg hdr;
  36         u32 mask;
  37         u16 resource;
  38         u8 group;
  39         u8 enable;
  40 } __packed;
  41
  42 static struct imx_sc_ipc *imx_sc_irq_ipc_handle;
  43 static struct work_struct imx_sc_irq_work;
  44 static ATOMIC_NOTIFIER_HEAD(imx_scu_irq_notifier_chain);
  45
  46 int imx_scu_irq_register_notifier(struct notifier_block *nb)
  47 {
  48         return atomic_notifier_chain_register(
  49                 &imx_scu_irq_notifier_chain, nb);
  50 }
  51 EXPORT_SYMBOL(imx_scu_irq_register_notifier);
  52
  53 int imx_scu_irq_unregister_notifier(struct notifier_block *nb)
  54 {
  55         return atomic_notifier_chain_unregister(
  56                 &imx_scu_irq_notifier_chain, nb);
  57 }
  58 EXPORT_SYMBOL(imx_scu_irq_unregister_notifier);
  59
  60 static int imx_scu_irq_notifier_call_chain(unsigned long status, u8 *group)
  61 {
  62         return atomic_notifier_call_chain(&imx_scu_irq_notifier_chain,
  63                 status, (void *)group);
  64 }
  65
  66 static void imx_scu_irq_work_handler(struct work_struct *work)
  67 {
  68         struct imx_sc_msg_irq_get_status msg;
  69         struct imx_sc_rpc_msg *hdr = &msg.hdr;
  70         u32 irq_status;
  71         int ret;
  72         u8 i;
  73
  74         for (i = 0; i < IMX_SC_IRQ_NUM_GROUP; i++) {
  75                 hdr->ver = IMX_SC_RPC_VERSION;
  76                 hdr->svc = IMX_SC_RPC_SVC_IRQ;
  77                 hdr->func = IMX_SC_IRQ_FUNC_STATUS;
  78                 hdr->size = 2;
  79
  80                 msg.data.req.resource = mu_resource_id;
  81                 msg.data.req.group = i;
  82
  83                 ret = imx_scu_call_rpc(imx_sc_irq_ipc_handle, &msg, true);
  84                 if (ret) {
  85                         pr_err("get irq group %d status failed, ret %d\n",
  86                                i, ret);
  87                         return;
  88                 }
  89
  90                 irq_status = msg.data.resp.status;
  91                 if (!irq_status)
  92                         continue;
  93
  94                 imx_scu_irq_notifier_call_chain(irq_status, &i);
  95         }
  96 }
  97
  98 int imx_scu_irq_group_enable(u8 group, u32 mask, u8 enable)
  99 {
 100         struct imx_sc_msg_irq_enable msg;
 101         struct imx_sc_rpc_msg *hdr = &msg.hdr;
 102         int ret;
 103
 104         if (!imx_sc_irq_ipc_handle)
 105                 return -EPROBE_DEFER;
 106
 107         hdr->ver = IMX_SC_RPC_VERSION;
 108         hdr->svc = IMX_SC_RPC_SVC_IRQ;
 109         hdr->func = IMX_SC_IRQ_FUNC_ENABLE;
 110         hdr->size = 3;
 111
 112         msg.resource = mu_resource_id;
 113         msg.group = group;
 114         msg.mask = mask;
 115         msg.enable = enable;
 116
 117         ret = imx_scu_call_rpc(imx_sc_irq_ipc_handle, &msg, true);
 118         if (ret)
 119                 pr_err("enable irq failed, group %d, mask %d, ret %d\n",
 120                         group, mask, ret);
 121
 122         return ret;
 123 }
 124 EXPORT_SYMBOL(imx_scu_irq_group_enable);
 125
 126 static void imx_scu_irq_callback(struct mbox_client *c, void *msg)
 127 {
 128         schedule_work(&imx_sc_irq_work);
 129 }
 130
 131 int imx_scu_enable_general_irq_channel(struct device *dev)
 132 {
 133         struct of_phandle_args spec;
 134         struct mbox_client *cl;
 135         struct mbox_chan *ch;
 136         int ret = 0, i = 0;
 137
 138         ret = imx_scu_get_handle(&imx_sc_irq_ipc_handle);
 139         if (ret)
 140                 return ret;
 141
 142         cl = devm_kzalloc(dev, sizeof(*cl), GFP_KERNEL);
 143         if (!cl)
 144                 return -ENOMEM;
 145
 146         cl->dev = dev;
 147         cl->rx_callback = imx_scu_irq_callback;
 148
 149         /* SCU general IRQ uses general interrupt channel 3 */
 150         ch = mbox_request_channel_byname(cl, "gip3");
 151         if (IS_ERR(ch)) {
 152                 ret = PTR_ERR(ch);
 153                 dev_err(dev, "failed to request mbox chan gip3, ret %d\n", ret);
 154                 devm_kfree(dev, cl);
 155                 return ret;
 156         }
 157
 158         INIT_WORK(&imx_sc_irq_work, imx_scu_irq_work_handler);
 159
 160         if (!of_parse_phandle_with_args(dev->of_node, "mboxes",
 161                                        "#mbox-cells", 0, &spec))
 162                 i = of_alias_get_id(spec.np, "mu");
 163
 164         /* use mu1 as general mu irq channel if failed */
 165         if (i < 0)
 166                 i = 1;
 167
 168         mu_resource_id = IMX_SC_R_MU_0A + i;
 169
 170         return ret;
 171 }
 172 EXPORT_SYMBOL(imx_scu_enable_general_irq_channel);