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