freebsd-dev/sys/arm/qualcomm/qcom_scm_legacy_defs.h
Adrian Chadd 960e65d23a qcom: add initial SCM legacy API
This is a very simple implementation of Qualcomm's SCM API.

It is just the structure/field definitions and the atomic SCM
call which doesn't use the structs yet - it uses the field
definitions inside registers.

I've tested that setting the cold boot address via the atomic
API is fine - Linux does the same thing.  But not all SCM calls
can be done via the legacy API.

This is a reimplementation based on the Linux qualcomm SCM legacy
code and definitions.

Tested:

* Qualcomm IPQ4018 AP, as part of other changes for doing SMP bring-up

Reviewed by: andrew, manu, imp
Differential Revision: https://reviews.freebsd.org/D32723
2021-11-04 09:02:33 -07:00

150 lines
4.9 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2021 Adrian Chadd <adrian@FreeBSD.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef __QCOM_SCM_LEGACY_DEFS_H__
#define __QCOM_SCM_LEGACY_DEFS_H__
/*
* These definitions are specific to the 32 bit legacy SCM interface
* used by the IPQ806x and IPQ401x SoCs.
*/
/*
* Mapping of the SCM service/command fields into the a0 argument
* in an SMC instruction call.
*
* This is particular to the legacy SCM interface, and is not the
* same as the non-legacy 32/64 bit FNID mapping layout.
*/
#define QCOM_SCM_LEGACY_SMC_FNID(s, c) (((s) << 10) | ((c) & 0x3ff))
/*
* There are two kinds of SCM calls in this legacy path.
*
* The first kind are the normal ones - up to a defined max of arguments,
* a defined max of responses and some identifiers for all of it.
* They can be issues in parallel on different cores, can be interrupted,
* etc.
*
* The second kind are what are termed "atomic" SCM calls -
* up to 5 argument DWORDs, up to 3 response DWORDs, done atomically,
* not interruptable/parallel.
*
* The former use the structures below to represent the request and response
* in memory. The latter use defines and a direct SMC call with the
* arguments in registers.
*/
struct qcom_scm_legacy_smc_args {
uint32_t args[8];
};
/*
* Atomic SCM call command/response buffer definitions.
*/
#define QCOM_SCM_LEGACY_ATOMIC_MAX_ARGCOUNT 5
#define QCOM_SCM_LEGACY_CLASS_REGISTER (0x2 << 8)
#define QCOM_SCM_LEGACY_MASK_IRQS (1U << 5)
/*
* Mapping an SCM service/command/argcount into the a0 register
* for an SMC instruction call.
*/
#define QCOM_SCM_LEGACY_ATOMIC_ID(svc, cmd, n) \
((QCOM_SCM_LEGACY_SMC_FNID((svc), cmd) << 12) | \
QCOM_SCM_LEGACY_CLASS_REGISTER | \
QCOM_SCM_LEGACY_MASK_IRQS | \
((n) & 0xf))
/*
* Legacy command/response buffer definitions.
*
* The legacy path contains up to the defined maximum arguments
* but only a single command/response pair per call.
*
* A command and response buffer is laid out in memory as such:
*
* | command header |
* | (buffer payload) |
* | response header |
* | (response payload) |
*/
/*
* The command header.
*
* len - the length of the total command and response, including
* the headers.
*
* buf_offset - the offset inside the buffer, starting at the
* beginning of this command header, where the command buffer
* is found. The end is the byte before the response_header_offset.
*
* response_header_offset - the offset inside the buffer where
* the response header is found.
*
* id - the QCOM_SCM_LEGACY_SMC_FNID() - service/command ids
*/
struct qcom_scm_legacy_command_header {
uint32_t len;
uint32_t buf_offset;
uint32_t response_header_offset;
uint32_t id;
};
/*
* The response header.
*
* This is found immediately after the command header and command
* buffer payload.
*
* len - the total amount of memory available for the response.
* Linux doesn't set this; it always passes in a response
* buffer large enough to store MAX_QCOM_SCM_RETS * DWORD
* bytes.
*
* It's also possible this is set by the firmware.
*
* buf_offset - start of response buffer, relative to the beginning
* of the command header. This also isn't set in Linux before
* calling the SMC instruction, but it is checked afterwards
* to assemble a pointer to the response data. The firmware
* likely sets this.
*
* is_complete - true if complete. Linux loops over DMA sync to
* check if this is complete even after the SMC call returns.
*/
struct qcom_scm_legacy_response_header {
uint32_t len;
uint32_t buf_offset;
uint32_t is_complete;
};
#endif /* __QCOM_SCM_LEGACY_DEFS_H__ */