board_periph_mstp.c File Reference

Module Stop Control (MSTPCRA..E) register block for ra8_emulator. More...

#include <stdint.h>
#include <stdio.h>
#include "board_periph_block.h"
#include "board_periph_mstp_internal.h"
#include "emu_host_io_internal.h"
#include "ra8_attributes.h"

Include dependency graph for board_periph_mstp.c:

Go to the source code of this file.

Enumerations
enum	mstp_order_t : uint32_t { k_mstp_block_order = 168U }
	Per-tick order slot for the MSTP block (just before SYSC-PRCR). More...

Functions
static uint64_t	internal_mstp_read (uc_engine *uc, uint64_t addr, unsigned size)
	MMIO read of MSTPCRA..E: answer from the tracked shadow.
static void	internal_mstp_write (uc_engine *uc, uint64_t addr, unsigned size, uint64_t value)
	MMIO write of MSTPCRA..E: fold into the shadow (ungate/re-gate).
static void	internal_mstp_report (void)
	End-of-run section: make any access to an unclocked block LOUD.
static void	internal_mstp_block_register (void)
	Register the MSTP block before main (host constructor).

Variables
static const board_periph_block_t	s_k_mstp_block
	MSTP block descriptor (owns MSTPCRA..E; self-registered).

Detailed Description

Module Stop Control (MSTPCRA..E) register block for ra8_emulator.

The board_periph block that owns the R_MSTP window (0x4020_3000, HUM Ch 11.2.6..11.2.10 p 443-450): it answers firmware reads/writes of MSTPCRA..MSTPCRE from the tracked shadow in board_periph_mstp_model.c, so the mandated read-back after an ungate settles deterministically and the shadow the address->bit gate table consults stays current.

The gate ENFORCEMENT lives in the board_periph core: before dispatching an MMIO access to any owning block, board_periph.c calls priv_board_mstp_addr_stopped and – when the peripheral is module-stopped – reads 0 / drops the write, matching the silicon (a stopped module is unclocked and does not respond). This file is only the register window plus the reset hook and the end-of-run "you touched an unclocked peripheral" report; the model half is engine-free so it can be unit-tested on the host.

Splitting the model out of this file is what lets the gate table be tested without Unicorn (tests/misc/src/test_ra8_emulator_mstp_gate.c); this glue is the thin part that the core registry needs and that pulls in board_periph_block.h.

Copyright

Copyright (c) 2026 Brighton Sikarskie SPDX-License-Identifier: MIT

Since

0.1.0

Definition in file board_periph_mstp.c.

Enumeration Type Documentation

mstp_order_t

enum mstp_order_t : uint32_t

Per-tick order slot for the MSTP block (just before SYSC-PRCR).

Enumerator
k_mstp_block_order	Groups with the PRCR / power-domain blocks.

Definition at line 38 of file board_periph_mstp.c.

Function Documentation

internal_mstp_block_register()

void internal_mstp_block_register ( void )

static

Register the MSTP block before main (host constructor).

Definition at line 118 of file board_periph_mstp.c.

References board_periph_register_block(), priv_board_mstp_reset(), RA8_INTERNAL, and s_k_mstp_block.

internal_mstp_read()

uint64_t internal_mstp_read ( uc_engine * uc, uint64_t addr, unsigned size )

static

MMIO read of MSTPCRA..E: answer from the tracked shadow.

MMIO read of mstpcra..e: answer from the tracked shadow; this step is contained within the board periph module-stop model and uses bounded caller or module-owned storage.

Parameters

[in,out]	uc	Unicorn engine whose emulated state is read or updated.
[in]	addr	Guest address involved in the operation.
[in]	size	Size of the requested region or access in bytes.

Returns

The module-stop read result produced by the board periph module-stop model.

Return values

value

The operation-specific module-stop read value.

Precondition

Arguments satisfy the ranges documented for module-stop read.

The call executes on the emulator's single owning thread.

Postcondition

State changes remain confined to the board periph module-stop model and documented output objects.

Ownership of caller-supplied storage is unchanged.

Note

The operation is synchronous and does not transfer heap ownership.

Since

0.1.0

Definition at line 55 of file board_periph_mstp.c.

References k_board_mstp_win_base, priv_board_mstp_read_reg(), and RA8_INTERNAL.

internal_mstp_report()

void internal_mstp_report ( void )

static

End-of-run section: make any access to an unclocked block LOUD.

End-of-run section: make any access to an unclocked block loud; this step is contained within the board periph module-stop model and uses bounded caller or module-owned storage.

Precondition

Arguments satisfy the ranges documented for module-stop report.

The call executes on the emulator's single owning thread.

Postcondition

State changes remain confined to the board periph module-stop model and documented output objects.

Ownership of caller-supplied storage is unchanged.

Note

The operation is synchronous and does not transfer heap ownership.

Since

0.1.0

Definition at line 88 of file board_periph_mstp.c.

References priv_board_mstp_gated_read_count(), priv_board_mstp_gated_write_count(), priv_board_mstp_last_gated_name(), priv_emu_io_errf(), and RA8_INTERNAL.

internal_mstp_write()

void internal_mstp_write ( uc_engine * uc, uint64_t addr, unsigned size, uint64_t value )

static

MMIO write of MSTPCRA..E: fold into the shadow (ungate/re-gate).

MMIO write of mstpcra..e: fold into the shadow (ungate/re-gate); this step is contained within the board periph module-stop model and uses bounded caller or module-owned storage.

Parameters

[in,out]	uc	Unicorn engine whose emulated state is read or updated.
[in]	addr	Guest address involved in the operation.
[in]	size	Size of the requested region or access in bytes.
[in]	value	Register or payload value involved in the operation.

Precondition

Arguments satisfy the ranges documented for module-stop write.

The call executes on the emulator's single owning thread.

Postcondition

State changes remain confined to the board periph module-stop model and documented output objects.

Ownership of caller-supplied storage is unchanged.

Note

The operation is synchronous and does not transfer heap ownership.

Since

0.1.0

Definition at line 74 of file board_periph_mstp.c.

References k_board_mstp_win_base, and priv_board_mstp_apply_write().

Variable Documentation

s_k_mstp_block

const board_periph_block_t s_k_mstp_block

static

Initial value:

                                                 = {
  .base   = (uint64_t)k_board_mstp_win_base,
  .span   = (uint64_t)k_board_mstp_win_span,
  .order  = (uint32_t)k_mstp_block_order,
  .read   = internal_mstp_read,
  .write  = internal_mstp_write,
  .tick   = nullptr,
  .reset  = priv_board_mstp_reset,
  .report = internal_mstp_report,
  .name   = "MSTP",
}

MSTP block descriptor (owns MSTPCRA..E; self-registered).

Definition at line 105 of file board_periph_mstp.c.

Referenced by internal_mstp_block_register().