path: root/src/rtos/ChibiOS.c

/***************************************************************************
 *   Copyright (C) 2012 by Matthias Blaicher                               *
 *   Matthias Blaicher - matthias@blaicher.com                             *
 *                                                                         *
 *   Copyright (C) 2011 by Broadcom Corporation                            *
 *   Evan Hunter - ehunter@broadcom.com                                    *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.           *
 ***************************************************************************/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <helper/time_support.h>
#include <jtag/jtag.h>
#include "target/target.h"
#include "target/target_type.h"
#include "target/armv7m.h"
#include "target/cortex_m.h"
#include "rtos.h"
#include "helper/log.h"
#include "helper/types.h"
#include "rtos_chibios_stackings.h"


/**
 * @brief   ChibiOS/RT memory signature record.
 *
 * @details Definition copied from os/kernel/include/chregistry.h of ChibiOS/RT.
 */
struct ChibiOS_chdebug {
	char      ch_identifier[4];       /**< @brief Always set to "main".       */
	uint8_t   ch_zero;                /**< @brief Must be zero.               */
	uint8_t   ch_size;                /**< @brief Size of this structure.     */
	uint16_t  ch_version;             /**< @brief Encoded ChibiOS/RT version. */
	uint8_t   ch_ptrsize;             /**< @brief Size of a pointer.          */
	uint8_t   ch_timesize;            /**< @brief Size of a @p systime_t.     */
	uint8_t   ch_threadsize;          /**< @brief Size of a @p Thread struct. */
	uint8_t   cf_off_prio;            /**< @brief Offset of @p p_prio field.  */
	uint8_t   cf_off_ctx;             /**< @brief Offset of @p p_ctx field.   */
	uint8_t   cf_off_newer;           /**< @brief Offset of @p p_newer field. */
	uint8_t   cf_off_older;           /**< @brief Offset of @p p_older field. */
	uint8_t   cf_off_name;            /**< @brief Offset of @p p_name field.  */
	uint8_t   cf_off_stklimit;        /**< @brief Offset of @p p_stklimit
												field.                        */
	uint8_t   cf_off_state;           /**< @brief Offset of @p p_state field. */
	uint8_t   cf_off_flags;           /**< @brief Offset of @p p_flags field. */
	uint8_t   cf_off_refs;            /**< @brief Offset of @p p_refs field.  */
	uint8_t   cf_off_preempt;         /**< @brief Offset of @p p_preempt
												field.                        */
	uint8_t   cf_off_time;            /**< @brief Offset of @p p_time field.  */
};

#define GET_CH_KERNEL_MAJOR(codedVersion) ((codedVersion >> 11) & 0x1f)
#define GET_CH_KERNEL_MINOR(codedVersion) ((codedVersion >> 6) & 0x1f)
#define GET_CH_KERNEL_PATCH(codedVersion) ((codedVersion >> 0) & 0x3f)

/**
 * @brief ChibiOS thread states.
 */
const char *ChibiOS_thread_states[] = {
	"READY", "CURRENT", "SUSPENDED", "WTSEM", "WTMTX", "WTCOND", "SLEEPING",
	"WTEXIT", "WTOREVT", "WTANDEVT", "SNDMSGQ", "SNDMSG", "WTMSG", "WTQUEUE",
	"FINAL"
};

#define CHIBIOS_NUM_STATES (sizeof(ChibiOS_thread_states)/sizeof(char *))

/* Maximum ChibiOS thread name. There is no real limit set by ChibiOS but 64
 * chars ought to be enough.
 */
#define CHIBIOS_THREAD_NAME_STR_SIZE (64)

struct ChibiOS_params {
	const char *target_name;

	struct ChibiOS_chdebug *signature;
	const struct rtos_register_stacking *stacking_info;
};

struct ChibiOS_params ChibiOS_params_list[] = {
	{
	"cortex_m",							/* target_name */
	0,
	NULL,									/* stacking_info */
	},
	{
	"hla_target",							/* target_name */
	0,
	NULL,									/* stacking_info */
	}
};
#define CHIBIOS_NUM_PARAMS ((int)(sizeof(ChibiOS_params_list)/sizeof(struct ChibiOS_params)))

static int ChibiOS_detect_rtos(struct target *target);
static int ChibiOS_create(struct target *target);
static int ChibiOS_update_threads(struct rtos *rtos);
static int ChibiOS_get_thread_reg_list(struct rtos *rtos, int64_t thread_id, char **hex_reg_list);
static int ChibiOS_get_symbol_list_to_lookup(symbol_table_elem_t *symbol_list[]);

struct rtos_type ChibiOS_rtos = {
	.name = "ChibiOS",

	.detect_rtos = ChibiOS_detect_rtos,
	.create = ChibiOS_create,
	.update_threads = ChibiOS_update_threads,
	.get_thread_reg_list = ChibiOS_get_thread_reg_list,
	.get_symbol_list_to_lookup = ChibiOS_get_symbol_list_to_lookup,
};

enum ChibiOS_symbol_values {
	ChibiOS_VAL_rlist = 0,
	ChibiOS_VAL_ch_debug = 1,
	ChibiOS_VAL_chSysInit = 2
};

static char *ChibiOS_symbol_list[] = {
	"rlist",		/* Thread ready list*/
	"ch_debug",		/* Memory Signatur containing offsets of fields in rlist*/
	"chSysInit",	/* Necessary part of API, used for ChibiOS detection*/
	NULL
};

static int ChibiOS_update_memory_signature(struct rtos *rtos)
{
	int retval;
	struct ChibiOS_params *param;
	struct ChibiOS_chdebug *signature;

	param = (struct ChibiOS_params *) rtos->rtos_specific_params;

	/* Free existing memory description.*/
	if (param->signature) {
		free(param->signature);
		param->signature = 0;
	}

	signature = malloc(sizeof(*signature));
	if (!signature) {
		LOG_ERROR("Could not allocate space for ChibiOS/RT memory signature");
		return -1;
	}

	retval = target_read_buffer(rtos->target,
								rtos->symbols[ChibiOS_VAL_ch_debug].address,
								sizeof(*signature),
								(uint8_t *) signature);
	if (retval != ERROR_OK) {
		LOG_ERROR("Could not read ChibiOS/RT memory signature from target");
		goto errfree;
	}

	if (strncmp(signature->ch_identifier, "main", 4) != 0) {
		LOG_ERROR("Memory signature identifier does not contain magic bytes.");
		goto errfree;
	}

	if (signature->ch_size < sizeof(*signature)) {
		LOG_ERROR("ChibiOS/RT memory signature claims to be smaller "
				"than expected");
		goto errfree;
	}

	if (signature->ch_size > sizeof(*signature)) {
		LOG_WARNING("ChibiOS/RT memory signature claims to be bigger than"
					" expected. Assuming compatibility...");
	}

	/* Convert endianness of version field */
	const uint8_t *versionTarget = (const uint8_t *)
										&signature->ch_version;
	signature->ch_version = rtos->target->endianness == TARGET_LITTLE_ENDIAN ?
			le_to_h_u32(versionTarget) : be_to_h_u32(versionTarget);

	const uint16_t ch_version = signature->ch_version;
	LOG_INFO("Successfully loaded memory map of ChibiOS/RT target "
			"running version %i.%i.%i", GET_CH_KERNEL_MAJOR(ch_version),
			GET_CH_KERNEL_MINOR(ch_version), GET_CH_KERNEL_PATCH(ch_version));

	/* Currently, we have the inherent assumption that all address pointers
	 * are 32 bit wide. */
	if (signature->ch_ptrsize != sizeof(uint32_t)) {
		LOG_ERROR("ChibiOS/RT target memory signature claims an address"
				  "width unequal to 32 bits!");
		free(signature);
		return -1;
	}

	param->signature = signature;
	return 0;

errfree:
	/* Error reading the ChibiOS memory structure */
	free(signature);
	param->signature = 0;
	return -1;
}


static int ChibiOS_update_stacking(struct rtos *rtos)
{
	/* Sometimes the stacking can not be determined only by looking at the
	 * target name but only a runtime.
	 *
	 * For example, this is the case for cortex-m4 targets and ChibiOS which
	 * only stack the FPU registers if it is enabled during ChibiOS build.
	 *
	 * Terminating which stacking is used is target depending.
	 *
	 * Assumptions:
	 *  - Once ChibiOS is actually initialized, the stacking is fixed.
	 *  - During startup code, the FPU might not be initialized and the
	 *    detection might fail.
	 *  - Since no threads are running during startup, the problem is solved
	 *    by delaying stacking detection until there are more threads
	 *    available than the current execution. In which case
	 *    ChibiOS_get_thread_reg_list is called.
	 */
	int retval;

	if (!rtos->rtos_specific_params)
		return -1;

	struct ChibiOS_params *param;
	param = (struct ChibiOS_params *) rtos->rtos_specific_params;

	/* Check for armv7m with *enabled* FPU, i.e. a Cortex M4  */
	struct armv7m_common *armv7m_target = target_to_armv7m(rtos->target);
	if (is_armv7m(armv7m_target)) {
		if (armv7m_target->fp_feature == FPv4_SP) {
			/* Found ARM v7m target which includes a FPU */
			uint32_t cpacr;

			retval = target_read_u32(rtos->target, FPU_CPACR, &cpacr);
			if (retval != ERROR_OK) {
				LOG_ERROR("Could not read CPACR register to check FPU state");
				return -1;
			}

			/* Check if CP10 and CP11 are set to full access.
			 * In ChibiOS this is done in ResetHandler() in crt0.c */
			if (cpacr & 0x00F00000) {
				/* Found target with enabled FPU */
				/* FIXME: Need to figure out how to specify the FPU registers */
				LOG_ERROR("ChibiOS ARM v7m targets with enabled FPU "
						  " are NOT supported");
				return -1;
			}
		}

		/* Found ARM v7m target with no or disabled FPU */
		param->stacking_info = &rtos_chibios_arm_v7m_stacking;
		return 0;
	}

	return -1;
}

static int ChibiOS_update_threads(struct rtos *rtos)
{
	int retval;
	const struct ChibiOS_params *param;
	int tasks_found = 0;
	int rtos_valid =