uboot/u-boot-stm32mp-2020.01/drivers/axi/axi_sandbox.c

78 lines
1.9 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2018
* Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc
*/
#include <common.h>
#include <axi.h>
#include <dm.h>
#include <asm/axi.h>
/*
* This driver implements a AXI bus for the sandbox architecture for testing
* purposes.
*
* The bus forwards every access to it to a special AXI emulation device (which
* it gets via the axi_emul_get_ops function) that implements a simple
* read/write storage.
*
* The emulator device must still be contained in the device tree in the usual
* way, since configuration data for the storage is read from the DT.
*/
static int axi_sandbox_read(struct udevice *bus, ulong address, void *data,
enum axi_size_t size)
{
struct axi_emul_ops *ops;
struct udevice *emul;
int ret;
/* Get emulator device */
ret = axi_sandbox_get_emul(bus, address, size, &emul);
if (ret)
return ret == -ENODEV ? 0 : ret;
/* Forward all reads to the AXI emulator */
ops = axi_emul_get_ops(emul);
if (!ops || !ops->read)
return -ENOSYS;
return ops->read(emul, address, data, size);
}
static int axi_sandbox_write(struct udevice *bus, ulong address, void *data,
enum axi_size_t size)
{
struct axi_emul_ops *ops;
struct udevice *emul;
int ret;
/* Get emulator device */
ret = axi_sandbox_get_emul(bus, address, size, &emul);
if (ret)
return ret == -ENODEV ? 0 : ret;
/* Forward all writes to the AXI emulator */
ops = axi_emul_get_ops(emul);
if (!ops || !ops->write)
return -ENOSYS;
return ops->write(emul, address, data, size);
}
static const struct udevice_id axi_sandbox_ids[] = {
{ .compatible = "sandbox,axi" },
{ /* sentinel */ }
};
static const struct axi_ops axi_sandbox_ops = {
.read = axi_sandbox_read,
.write = axi_sandbox_write,
};
U_BOOT_DRIVER(axi_sandbox_bus) = {
.name = "axi_sandbox_bus",
.id = UCLASS_AXI,
.of_match = axi_sandbox_ids,
.ops = &axi_sandbox_ops,
};