soc: apple: Add RTKit IPC library

	  controls for SoC devices. This driver manages them through the

	  generic power domain framework, and also provides reset support.

config APPLE_RTKIT

	tristate "Apple RTKit co-processor IPC protocol"

	depends on MAILBOX

	depends on ARCH_APPLE || COMPILE_TEST

	default ARCH_APPLE

	help

	  Apple SoCs such as the M1 come with various co-processors running

	  their proprietary RTKit operating system. This option enables support

	  for the protocol library used to communicate with those. It is used

	  by various client drivers.

	  Say 'y' here if you have an Apple SoC.

endmenu

endif

# SPDX-License-Identifier: GPL-2.0-only

obj-$(CONFIG_APPLE_PMGR_PWRSTATE)	+= apple-pmgr-pwrstate.o

obj-$(CONFIG_APPLE_RTKIT) += apple-rtkit.o

apple-rtkit-y = rtkit.o rtkit-crashlog.o

// SPDX-License-Identifier: GPL-2.0-only OR MIT

/*

 * Apple RTKit IPC library

 * Copyright (C) The Asahi Linux Contributors

 */

#include "rtkit-internal.h"

#define FOURCC(a, b, c, d) \

	(((u32)(a) << 24) | ((u32)(b) << 16) | ((u32)(c) << 8) | ((u32)(d)))

#define APPLE_RTKIT_CRASHLOG_HEADER FOURCC('C', 'L', 'H', 'E')

#define APPLE_RTKIT_CRASHLOG_STR FOURCC('C', 's', 't', 'r')

#define APPLE_RTKIT_CRASHLOG_VERSION FOURCC('C', 'v', 'e', 'r')

#define APPLE_RTKIT_CRASHLOG_MBOX FOURCC('C', 'm', 'b', 'x')

#define APPLE_RTKIT_CRASHLOG_TIME FOURCC('C', 't', 'i', 'm')

struct apple_rtkit_crashlog_header {

	u32 fourcc;

	u32 version;

	u32 size;

	u32 flags;

	u8 _unk[16];

};

static_assert(sizeof(struct apple_rtkit_crashlog_header) == 0x20);

struct apple_rtkit_crashlog_mbox_entry {

	u64 msg0;

	u64 msg1;

	u32 timestamp;

	u8 _unk[4];

};

static_assert(sizeof(struct apple_rtkit_crashlog_mbox_entry) == 0x18);

static void apple_rtkit_crashlog_dump_str(struct apple_rtkit *rtk, u8 *bfr,

					  size_t size)

{

	u32 idx;

	u8 *ptr, *end;

	memcpy(&idx, bfr, 4);

	ptr = bfr + 4;

	end = bfr + size;

	while (ptr < end) {

		u8 *newline = memchr(ptr, '\n', end - ptr);

		if (newline) {

			u8 tmp = *newline;

			*newline = '\0';

			dev_warn(rtk->dev, "RTKit: Message (id=%x): %s\n", idx,

				 ptr);

			*newline = tmp;

			ptr = newline + 1;

		} else {

			dev_warn(rtk->dev, "RTKit: Message (id=%x): %s", idx,

				 ptr);

			break;

		}

	}

}

static void apple_rtkit_crashlog_dump_version(struct apple_rtkit *rtk, u8 *bfr,

					      size_t size)

{

	dev_warn(rtk->dev, "RTKit: Version: %s", bfr + 16);

}

static void apple_rtkit_crashlog_dump_time(struct apple_rtkit *rtk, u8 *bfr,

					   size_t size)

{

	u64 crash_time;

	memcpy(&crash_time, bfr, 8);

	dev_warn(rtk->dev, "RTKit: Crash time: %lld", crash_time);

}

static void apple_rtkit_crashlog_dump_mailbox(struct apple_rtkit *rtk, u8 *bfr,

					      size_t size)

{

	u32 type, index, i;

	size_t n_messages;

	struct apple_rtkit_crashlog_mbox_entry entry;

	memcpy(&type, bfr + 16, 4);

	memcpy(&index, bfr + 24, 4);

	n_messages = (size - 28) / sizeof(entry);

	dev_warn(rtk->dev, "RTKit: Mailbox history (type = %d, index = %d)",

		 type, index);

	for (i = 0; i < n_messages; ++i) {

		memcpy(&entry, bfr + 28 + i * sizeof(entry), sizeof(entry));

		dev_warn(rtk->dev, "RTKit:  #%03d@%08x: %016llx %016llx", i,

			 entry.timestamp, entry.msg0, entry.msg1);

	}

}

void apple_rtkit_crashlog_dump(struct apple_rtkit *rtk, u8 *bfr, size_t size)

{

	size_t offset;

	u32 section_fourcc, section_size;

	struct apple_rtkit_crashlog_header header;

	memcpy(&header, bfr, sizeof(header));

	if (header.fourcc != APPLE_RTKIT_CRASHLOG_HEADER) {

		dev_warn(rtk->dev, "RTKit: Expected crashlog header but got %x",

			 header.fourcc);

		return;

	}

	if (header.size > size) {

		dev_warn(rtk->dev, "RTKit: Crashlog size (%x) is too large",

			 header.size);

		return;

	}

	size = header.size;

	offset = sizeof(header);

	while (offset < size) {

		memcpy(&section_fourcc, bfr + offset, 4);

		memcpy(&section_size, bfr + offset + 12, 4);

		switch (section_fourcc) {

		case APPLE_RTKIT_CRASHLOG_HEADER:

			dev_dbg(rtk->dev, "RTKit: End of crashlog reached");

			return;

		case APPLE_RTKIT_CRASHLOG_STR:

			apple_rtkit_crashlog_dump_str(rtk, bfr + offset + 16,

						      section_size);

			break;

		case APPLE_RTKIT_CRASHLOG_VERSION:

			apple_rtkit_crashlog_dump_version(

				rtk, bfr + offset + 16, section_size);

			break;

		case APPLE_RTKIT_CRASHLOG_MBOX:

			apple_rtkit_crashlog_dump_mailbox(

				rtk, bfr + offset + 16, section_size);

			break;

		case APPLE_RTKIT_CRASHLOG_TIME:

			apple_rtkit_crashlog_dump_time(rtk, bfr + offset + 16,

						       section_size);

			break;

		default:

			dev_warn(rtk->dev,

				 "RTKit: Unknown crashlog section: %x",

				 section_fourcc);

		}

		offset += section_size;

	}

	dev_warn(rtk->dev,

		 "RTKit: End of crashlog reached but no footer present");

}

/* SPDX-License-Identifier: GPL-2.0-only OR MIT */

/*

 * Apple RTKit IPC library

 * Copyright (C) The Asahi Linux Contributors

 */

#ifndef _APPLE_RTKIT_INTERAL_H

#define _APPLE_RTKIT_INTERAL_H

#include <linux/apple-mailbox.h>

#include <linux/bitfield.h>

#include <linux/bitmap.h>

#include <linux/completion.h>

#include <linux/dma-mapping.h>

#include <linux/io.h>

#include <linux/kernel.h>

#include <linux/mailbox_client.h>

#include <linux/module.h>

#include <linux/slab.h>

#include <linux/soc/apple/rtkit.h>

#include <linux/workqueue.h>

#define APPLE_RTKIT_APP_ENDPOINT_START 0x20

#define APPLE_RTKIT_MAX_ENDPOINTS 0x100

struct apple_rtkit {

	void *cookie;

	const struct apple_rtkit_ops *ops;

	struct device *dev;

	const char *mbox_name;

	int mbox_idx;

	struct mbox_client mbox_cl;

	struct mbox_chan *mbox_chan;

	struct completion epmap_completion;

	struct completion iop_pwr_ack_completion;

	struct completion ap_pwr_ack_completion;

	int boot_result;

	int version;

	unsigned int iop_power_state;

	unsigned int ap_power_state;

	bool crashed;

	DECLARE_BITMAP(endpoints, APPLE_RTKIT_MAX_ENDPOINTS);

	struct apple_rtkit_shmem ioreport_buffer;

	struct apple_rtkit_shmem crashlog_buffer;

	struct apple_rtkit_shmem syslog_buffer;

	char *syslog_msg_buffer;

	size_t syslog_n_entries;

	size_t syslog_msg_size;

	struct workqueue_struct *wq;

};

void apple_rtkit_crashlog_dump(struct apple_rtkit *rtk, u8 *bfr, size_t size);

#endif