drivers/mailbox/zynqmp-ipi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Xilinx Zynq MPSoC Mailbox driver
   4  *
   5  * Copyright (C) 2018-2019 Xilinx, Inc.
   6  */
   7
   8 #include <common.h>
   9 #include <asm/io.h>
  10 #include <dm.h>
  11 #include <mailbox-uclass.h>
  12 #include <dm/device_compat.h>
  13 #include <mach/sys_proto.h>
  14 #include <linux/ioport.h>
  15 #include <linux/io.h>
  16 #include <wait_bit.h>
  17
  18 /* IPI bitmasks, register base */
  19 /* TODO: move reg base to DT */
  20 #define IPI_BIT_MASK_PMU0     0x10000
  21 #define IPI_INT_REG_BASE_APU  0xFF300000
  22
  23 struct ipi_int_regs {
  24         u32 trig; /* 0x0  */
  25         u32 obs;  /* 0x4  */
  26         u32 ist;  /* 0x8  */
  27         u32 imr;  /* 0xC  */
  28         u32 ier;  /* 0x10 */
  29         u32 idr;  /* 0x14 */
  30 };
  31
  32 #define ipi_int_apu ((struct ipi_int_regs *)IPI_INT_REG_BASE_APU)
  33
  34 struct zynqmp_ipi {
  35         void __iomem *local_req_regs;
  36         void __iomem *local_res_regs;
  37         void __iomem *remote_req_regs;
  38         void __iomem *remote_res_regs;
  39 };
  40
  41 static int zynqmp_ipi_send(struct mbox_chan *chan, const void *data)
  42 {
  43         const struct zynqmp_ipi_msg *msg = (struct zynqmp_ipi_msg *)data;
  44         struct zynqmp_ipi *zynqmp = dev_get_priv(chan->dev);
  45         u32 ret;
  46         u32 *mbx = (u32 *)zynqmp->local_req_regs;
  47
  48         for (size_t i = 0; i < msg->len; i++)
  49                 writel(msg->buf[i], &mbx[i]);
  50
  51         /* Write trigger interrupt */
  52         writel(IPI_BIT_MASK_PMU0, &ipi_int_apu->trig);
  53
  54         /* Wait until observation bit is cleared */
  55         ret = wait_for_bit_le32(&ipi_int_apu->obs, IPI_BIT_MASK_PMU0, false,
  56                                 100, false);
  57
  58         debug("%s, send %ld bytes\n", __func__, msg->len);
  59         return ret;
  60 };
  61
  62 static int zynqmp_ipi_recv(struct mbox_chan *chan, void *data)
  63 {
  64         struct zynqmp_ipi_msg *msg = (struct zynqmp_ipi_msg *)data;
  65         struct zynqmp_ipi *zynqmp = dev_get_priv(chan->dev);
  66         u32 *mbx = (u32 *)zynqmp->local_res_regs;
  67
  68         for (size_t i = 0; i < msg->len; i++)
  69                 msg->buf[i] = readl(&mbx[i]);
  70
  71         debug("%s, recv %ld bytes\n", __func__, msg->len);
  72         return 0;
  73 };
  74
  75 static int zynqmp_ipi_probe(struct udevice *dev)
  76 {
  77         struct zynqmp_ipi *zynqmp = dev_get_priv(dev);
  78         struct resource res;
  79         ofnode node;
  80
  81         debug("%s(dev=%p)\n", __func__, dev);
  82
  83         /* Get subnode where the regs are defined */
  84         /* Note IPI mailbox node needs to be the first one in DT */
  85         node = ofnode_first_subnode(dev_ofnode(dev));
  86
  87         if (ofnode_read_resource_byname(node, "local_request_region", &res)) {
  88                 dev_err(dev, "No reg property for local_request_region\n");
  89                 return -EINVAL;
  90         };
  91         zynqmp->local_req_regs = devm_ioremap(dev, res.start,
  92                                               (res.start - res.end));
  93
  94         if (ofnode_read_resource_byname(node, "local_response_region", &res)) {
  95                 dev_err(dev, "No reg property for local_response_region\n");
  96                 return -EINVAL;
  97         };
  98         zynqmp->local_res_regs = devm_ioremap(dev, res.start,
  99                                               (res.start - res.end));
 100
 101         if (ofnode_read_resource_byname(node, "remote_request_region", &res)) {
 102                 dev_err(dev, "No reg property for remote_request_region\n");
 103                 return -EINVAL;
 104         };
 105         zynqmp->remote_req_regs = devm_ioremap(dev, res.start,
 106                                                (res.start - res.end));
 107
 108         if (ofnode_read_resource_byname(node, "remote_response_region", &res)) {
 109                 dev_err(dev, "No reg property for remote_response_region\n");
 110                 return -EINVAL;
 111         };
 112         zynqmp->remote_res_regs = devm_ioremap(dev, res.start,
 113                                                (res.start - res.end));
 114
 115         return 0;
 116 };
 117
 118 static const struct udevice_id zynqmp_ipi_ids[] = {
 119         { .compatible = "xlnx,zynqmp-ipi-mailbox" },
 120         { }
 121 };
 122
 123 struct mbox_ops zynqmp_ipi_mbox_ops = {
 124         .send = zynqmp_ipi_send,
 125         .recv = zynqmp_ipi_recv,
 126 };
 127
 128 U_BOOT_DRIVER(zynqmp_ipi) = {
 129         .name = "zynqmp-ipi",
 130         .id = UCLASS_MAILBOX,
 131         .of_match = zynqmp_ipi_ids,
 132         .probe = zynqmp_ipi_probe,
 133         .priv_auto_alloc_size = sizeof(struct zynqmp_ipi),
 134         .ops = &zynqmp_ipi_mbox_ops,
 135 };