u-boot/drivers/mailbox/zynqmp-ipi.c
Ibai Erkiaga 660b0c77d8 mailbox: zynqmp: ipi mailbox driver
ZynqMP mailbox driver implementing IPI communication with PMU. This would
allow U-Boot SPL to communicate with PMUFW to request privileged
operations.

Signed-off-by: Ibai Erkiaga <ibai.erkiaga-elorza@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
2019-10-08 09:55:11 +02:00

135 lines
3.5 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Xilinx Zynq MPSoC Mailbox driver
*
* Copyright (C) 2018-2019 Xilinx, Inc.
*/
#include <common.h>
#include <asm/io.h>
#include <dm.h>
#include <mailbox-uclass.h>
#include <mach/sys_proto.h>
#include <linux/ioport.h>
#include <linux/io.h>
#include <wait_bit.h>
/* IPI bitmasks, register base */
/* TODO: move reg base to DT */
#define IPI_BIT_MASK_PMU0 0x10000
#define IPI_INT_REG_BASE_APU 0xFF300000
struct ipi_int_regs {
u32 trig; /* 0x0 */
u32 obs; /* 0x4 */
u32 ist; /* 0x8 */
u32 imr; /* 0xC */
u32 ier; /* 0x10 */
u32 idr; /* 0x14 */
};
#define ipi_int_apu ((struct ipi_int_regs *)IPI_INT_REG_BASE_APU)
struct zynqmp_ipi {
void __iomem *local_req_regs;
void __iomem *local_res_regs;
void __iomem *remote_req_regs;
void __iomem *remote_res_regs;
};
static int zynqmp_ipi_send(struct mbox_chan *chan, const void *data)
{
const struct zynqmp_ipi_msg *msg = (struct zynqmp_ipi_msg *)data;
struct zynqmp_ipi *zynqmp = dev_get_priv(chan->dev);
u32 ret;
u32 *mbx = (u32 *)zynqmp->local_req_regs;
for (size_t i = 0; i < msg->len; i++)
writel(msg->buf[i], &mbx[i]);
/* Write trigger interrupt */
writel(IPI_BIT_MASK_PMU0, &ipi_int_apu->trig);
/* Wait until observation bit is cleared */
ret = wait_for_bit_le32(&ipi_int_apu->obs, IPI_BIT_MASK_PMU0, false,
100, false);
debug("%s, send %ld bytes\n", __func__, msg->len);
return ret;
};
static int zynqmp_ipi_recv(struct mbox_chan *chan, void *data)
{
struct zynqmp_ipi_msg *msg = (struct zynqmp_ipi_msg *)data;
struct zynqmp_ipi *zynqmp = dev_get_priv(chan->dev);
u32 *mbx = (u32 *)zynqmp->local_res_regs;
for (size_t i = 0; i < msg->len; i++)
msg->buf[i] = readl(&mbx[i]);
debug("%s, recv %ld bytes\n", __func__, msg->len);
return 0;
};
static int zynqmp_ipi_probe(struct udevice *dev)
{
struct zynqmp_ipi *zynqmp = dev_get_priv(dev);
struct resource res;
ofnode node;
debug("%s(dev=%p)\n", __func__, dev);
/* Get subnode where the regs are defined */
/* Note IPI mailbox node needs to be the first one in DT */
node = ofnode_first_subnode(dev_ofnode(dev));
if (ofnode_read_resource_byname(node, "local_request_region", &res)) {
dev_err(dev, "No reg property for local_request_region\n");
return -EINVAL;
};
zynqmp->local_req_regs = devm_ioremap(dev, res.start,
(res.start - res.end));
if (ofnode_read_resource_byname(node, "local_response_region", &res)) {
dev_err(dev, "No reg property for local_response_region\n");
return -EINVAL;
};
zynqmp->local_res_regs = devm_ioremap(dev, res.start,
(res.start - res.end));
if (ofnode_read_resource_byname(node, "remote_request_region", &res)) {
dev_err(dev, "No reg property for remote_request_region\n");
return -EINVAL;
};
zynqmp->remote_req_regs = devm_ioremap(dev, res.start,
(res.start - res.end));
if (ofnode_read_resource_byname(node, "remote_response_region", &res)) {
dev_err(dev, "No reg property for remote_response_region\n");
return -EINVAL;
};
zynqmp->remote_res_regs = devm_ioremap(dev, res.start,
(res.start - res.end));
return 0;
};
static const struct udevice_id zynqmp_ipi_ids[] = {
{ .compatible = "xlnx,zynqmp-ipi-mailbox" },
{ }
};
struct mbox_ops zynqmp_ipi_mbox_ops = {
.send = zynqmp_ipi_send,
.recv = zynqmp_ipi_recv,
};
U_BOOT_DRIVER(zynqmp_ipi) = {
.name = "zynqmp-ipi",
.id = UCLASS_MAILBOX,
.of_match = zynqmp_ipi_ids,
.probe = zynqmp_ipi_probe,
.priv_auto_alloc_size = sizeof(struct zynqmp_ipi),
.ops = &zynqmp_ipi_mbox_ops,
};