u-boot/include/sm.h
Alexey Romanov c52cd07407 drivers: introduce Secure Monitor uclass
At the moment, we don't have a common API for working with
SM, only the smc_call() function. This approach is not generic
and difficult to configure and maintain.

This patch adds UCLASS_SM with the generic API:

- sm_call()
- sm_call_write()
- sm_call_read()

These functions operate with struct pt_regs, which describes
Secure Monitor arguments.

Signed-off-by: Alexey Romanov <avromanov@salutedevices.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Link: https://lore.kernel.org/r/20230921081346.22157-2-avromanov@salutedevices.com
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
2023-10-15 12:23:48 +02:00

67 lines
1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright (c) 2023 SberDevices, Inc.
*
* Author: Alexey Romanov <avromanov@salutedevices.ru>
*/
#ifndef __SM_H__
#define __SM_H__
/*
* NOTE: UCLASS_SM is designed with the idea that
* each driver should convert @cmd to some raw
* value, which is known only for driver, and set this
* value to the first element of the @args->regs array.
* Therefore, it is necessary to pass the remaining
* arguments starting at index = 1. Anyway, driver
* implementation may vary, so, please, check the specific
* implementation of the driver you are using.
*/
#include <asm/types.h>
#include <asm/ptrace.h>
struct udevice;
/**
* sm_call - generic SMC call to the secure-monitor
*
* @dev: Pointer to UCLASS_SM device
* @cmd_index: Index of the SMC function ID
* @smc_ret: Returned value from secure world
* @args: SMC arguments
*
* @return: 0 on success, a negative value on error
*/
int sm_call(struct udevice *dev, u32 cmd, s32 *ret, struct pt_regs *args);
/**
* sm_call_read - retrieve data from secure-monitor
*
* @dev: Pointer to UCLASS_MESON_SM device
* @buffer: Buffer to store the retrieved data
* @size: Size of the buffer
* @cmd: Index of the SMC function ID
* @args: SMC arguments
*
* @return: size of read data on success, a negative value on error
*/
int sm_call_read(struct udevice *dev, void *buffer, size_t size,
u32 cmd, struct pt_regs *args);
/**
* sm_call_write - send data to secure-monitor
*
* @dev: Pointer to UCLASS_SM device
* @buffer: Buffer containing data to send
* @size: Size of the buffer
* @cmd: Index of the SMC function ID
* @args: SMC arguments
*
* @return: size of sent data on success, a negative value on error
*/
int sm_call_write(struct udevice *dev, void *buffer, size_t size,
u32 cmd, struct pt_regs *args);
#endif /* __SM_H__ */