u-boot/arch/sandbox/include/asm/axi.h

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/* SPDX-License-Identifier: GPL-2.0+ */
/*
* (C) Copyright 2018
* Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc
*/
#ifndef __asm_axi_h
#define __asm_axi_h
#define axi_emul_get_ops(dev) ((struct axi_emul_ops *)(dev)->driver->ops)
/**
* axi_sandbox_get_emul() - Retrieve a pointer to a AXI emulation device
* @bus: The AXI bus from which to retrieve a emulation device
* @address: The address of a transfer that should be handled by a emulation
* device
* @length: The data width of a transfer that should be handled by a emulation
* device
* @emulp: Pointer to a buffer receiving the emulation device that handles
* the transfer specified by the address and length parameters
*
* To test the AXI uclass, we implement a simple AXI emulation device, which is
* a virtual device on a AXI bus that exposes a simple storage interface: When
* reading and writing from the device, the addresses are translated to offsets
* within the device's storage. For write accesses the data is written to the
* specified storage offset, and for read accesses the data is read from the
* specified storage offset.
*
* A DTS entry might look like this:
*
* axi: axi@0 {
* compatible = "sandbox,axi";
* #address-cells = <0x1>;
* #size-cells = <0x1>;
* store@0 {
* compatible = "sandbox,sandbox_store";
* reg = <0x0 0x400>;
* };
* };
*
* This function may then be used to retrieve the pointer to the sandbox_store
* emulation device given the AXI bus device, and the data (address, data
* width) of a AXI transfer which should be handled by a emulation device.
*
* Return: 0 of OK, -ENODEV if no device capable of handling the specified
* transfer exists or the device could not be retrieved
*/
int axi_sandbox_get_emul(struct udevice *bus, ulong address, uint length,
struct udevice **emulp);
/**
* axi_get_store() - Get address of internal storage of a emulated AXI device
* @dev: Emulated AXI device to get the pointer of the internal storage
* for.
* @storep: Pointer to the internal storage of the emulated AXI device.
*
* To preset or read back the contents internal storage of the emulated AXI
* device, this function returns the pointer to the storage. Changes to the
* contents of the storage are reflected when using the AXI read/write API
* methods, and vice versa, so by using this method expected read data can be
* set up in advance, and written data can be checked in unit tests.
*
* Return: 0 if OK, -ve on error.
*/
int axi_get_store(struct udevice *dev, u8 **storep);
#endif /* __asm_axi_h */