Merge remote branch 'origin/master' into HEAD

[openocd.git] / src / target / arm946e.c

/***************************************************************************
 *   Copyright (C) 2005 by Dominic Rath                                    *
 *   Dominic.Rath@gmx.de                                                   *
 *                                                                         *
 *   Copyright (C) 2008 by Spencer Oliver                                  *
 *   spen@spen-soft.co.uk                                                  *
 *                                                                         *
 *   Copyright (C) 2010 by Drasko DRASKOVIC                                *
 *   drasko.draskovic@gmail.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.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "arm946e.h"
#include "target_type.h"
#include "arm_opcodes.h"

#include "breakpoints.h"

#if 0
#define _DEBUG_INSTRUCTION_EXECUTION_
#endif

#define NB_CACHE_WAYS 4

static uint32_t dc = 0x0;
static uint32_t ic = 0x0;

/**
 * flag to give info about cache manipulation during debug :
 * "0"  -       cache lines are invalidated "on the fly", for affected addresses.
 *                      This is prefered from performance point of view.
 * "1"  -       cache is invalidated and switched off on debug_entry, and switched back on on restore.
 *                      It is kept off during debugging.
 */
static uint8_t arm946e_preserve_cache;

int arm946e_post_debug_entry(struct target *target);
void arm946e_pre_restore_context(struct target *target);
static int arm946e_read_cp15(struct target *target, int reg_addr, uint32_t *value);


int arm946e_init_arch_info(struct target *target, struct arm946e_common *arm946e, struct jtag_tap *tap)
{
        struct arm7_9_common *arm7_9 = &arm946e->arm7_9_common;

        /* initialize arm7/arm9 specific info (including armv4_5) */
        arm9tdmi_init_arch_info(target, arm7_9, tap);

        arm946e->common_magic = ARM946E_COMMON_MAGIC;

        /**
         * The ARM946E-S implements the ARMv5TE architecture which
         * has the BKPT instruction, so we don't have to use a watchpoint comparator
         */
        arm7_9->arm_bkpt = ARMV5_BKPT(0x0);
        arm7_9->thumb_bkpt = ARMV5_T_BKPT(0x0) & 0xffff;


        arm7_9->post_debug_entry = arm946e_post_debug_entry;
        arm7_9->pre_restore_context = arm946e_pre_restore_context;

        /**
         * disabling linefills leads to lockups, so keep them enabled for now
         * this doesn't affect correctness, but might affect timing issues, if
         * important data is evicted from the cache during the debug session
         */
        arm946e_preserve_cache = 0;

        /* override hw single-step capability from ARM9TDMI */
        //arm7_9->has_single_step = 1;

        return ERROR_OK;
}

static int arm946e_target_create(struct target *target, Jim_Interp *interp)
{
        struct arm946e_common *arm946e = calloc(1,sizeof(struct arm946e_common));

        arm946e_init_arch_info(target, arm946e, target->tap);

        return ERROR_OK;
}

static int arm946e_verify_pointer(struct command_context *cmd_ctx,
                struct arm946e_common *arm946e)
{
        if (arm946e->common_magic != ARM946E_COMMON_MAGIC) {
                command_print(cmd_ctx, "target is not an ARM946");
                return ERROR_TARGET_INVALID;
        }
        return ERROR_OK;
}

/*
 * REVISIT:  The "read_cp15" and "write_cp15" commands could hook up
 * to eventual mrc() and mcr() routines ... the reg_addr values being
 * constructed (for CP15 only) from Opcode_1, Opcode_2, and CRn values.
 * See section 7.3 of the ARM946E-S TRM.
 */
static int arm946e_read_cp15(struct target *target, int reg_addr, uint32_t *value)
{
        int retval = ERROR_OK;
        struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
        struct arm_jtag *jtag_info = &arm7_9->jtag_info;
        struct scan_field fields[3];
        uint8_t reg_addr_buf = reg_addr & 0x3f;
        uint8_t nr_w_buf = 0;

        if ((retval = arm_jtag_scann(jtag_info, 0xf, TAP_IDLE)) != ERROR_OK)
        {
                return retval;
        }
        retval = arm_jtag_set_instr(jtag_info, jtag_info->intest_instr, NULL, TAP_IDLE);
        if (retval != ERROR_OK)
                return retval;

        fields[0].num_bits = 32;
        /* REVISIT: table 7-2 shows that bits 31-31 need to be
         * specified for accessing BIST registers ...
         */
        fields[0].out_value = NULL;
        fields[0].in_value = NULL;

        fields[1].num_bits = 6;
        fields[1].out_value = &reg_addr_buf;
        fields[1].in_value = NULL;

        fields[2].num_bits = 1;
        fields[2].out_value = &nr_w_buf;
        fields[2].in_value = NULL;

        jtag_add_dr_scan(jtag_info->tap, 3, fields, TAP_IDLE);

        fields[0].in_value = (uint8_t *)value;
        jtag_add_dr_scan(jtag_info->tap, 3, fields, TAP_IDLE);

        jtag_add_callback(arm_le_to_h_u32, (jtag_callback_data_t)value);

#ifdef _DEBUG_INSTRUCTION_EXECUTION_
        LOG_DEBUG("addr: 0x%x value: %8.8x", reg_addr, *value);
#endif

        if ((retval = jtag_execute_queue()) != ERROR_OK)
        {
                return retval;
        }

        return ERROR_OK;
}

int arm946e_write_cp15(struct target *target, int reg_addr, uint32_t value)
{
        int retval = ERROR_OK;
        struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
        struct arm_jtag *jtag_info = &arm7_9->jtag_info;
        struct scan_field fields[3];
        uint8_t reg_addr_buf = reg_addr & 0x3f;
        uint8_t nr_w_buf = 1;
        uint8_t value_buf[4];

        buf_set_u32(value_buf, 0, 32, value);

        if ((retval = arm_jtag_scann(jtag_info, 0xf, TAP_IDLE)) != ERROR_OK)
        {
                return retval;
        }
        retval = arm_jtag_set_instr(jtag_info, jtag_info->intest_instr, NULL, TAP_IDLE);
        if (retval != ERROR_OK)
                return retval;

        fields[0].num_bits = 32;
        fields[0].out_value = value_buf;
        fields[0].in_value = NULL;

        fields[1].num_bits = 6;
        fields[1].out_value = &reg_addr_buf;
        fields[1].in_value = NULL;

        fields[2].num_bits = 1;
        fields[2].out_value = &nr_w_buf;
        fields[2].in_value = NULL;

        jtag_add_dr_scan(jtag_info->tap, 3, fields, TAP_IDLE);

#ifdef _DEBUG_INSTRUCTION_EXECUTION_
        LOG_DEBUG("addr: 0x%x value: %8.8x", reg_addr, value);
#endif

        if ((retval = jtag_execute_queue()) != ERROR_OK)
        {
                return retval;
        }

        return ERROR_OK;
}

uint32_t arm946e_invalidate_whole_dcache(struct target *target)
{

   uint32_t csize = 0;
   uint32_t shift = 0;
   uint32_t cp15_idx, seg, dtag;
   int nb_idx, idx = 0;
   int retval;

   /* Get cache type */
   arm946e_read_cp15(target, 0x01, (uint32_t *) &csize);

   csize = (csize >> 18) & 0x0F;

        if (csize == 0)
                shift = 0;
        else
                shift = csize - 0x3; /* Now 0 = 4KB, 1 = 8KB, ... */

        /* Cache size, given in bytes */
        csize = 1 << (12 + shift);
        /* One line (index) is 32 bytes (8 words) long */
        nb_idx = (csize / 32);  /* gives nb of lines (indexes) in the cache */

        /* Loop for all segmentde (i.e. ways) */
        for( seg=0; seg < NB_CACHE_WAYS; seg++)
        {
                /* Loop for all indexes */
                for(idx=0; idx < nb_idx; idx++)
                {
                        /* Form and write cp15 index (segment + line idx) */
                        cp15_idx = seg << 30 | idx << 5;
                        retval = arm946e_write_cp15(target, 0x3a, cp15_idx);
                        if (retval != ERROR_OK)
                        {
                                LOG_DEBUG("ERROR writing index");
                                return retval;
                        }

                        /* Read dtag */
                        arm946e_read_cp15(target, 0x16, (uint32_t *) &dtag);

                        /* Check cache line VALID bit */
                        if ( !(dtag >> 4 & 0x1) )
                                continue;

                        /* Clean data cache line */
                        retval = arm946e_write_cp15(target, 0x35, 0x1);
                        if (retval != ERROR_OK)
                        {
                                LOG_DEBUG("ERROR cleaning cache line");
                                return retval;
                        }

                        /* Flush data cache line */
                        retval = arm946e_write_cp15(target, 0x1a, 0x1);
                        if (retval != ERROR_OK)
                        {
                                LOG_DEBUG("ERROR flushing cache line");
                                return retval;
                        }
                }
        }

        return ERROR_OK;
}

uint32_t arm946e_invalidate_whole_icache(struct target *target)
{
        int retval;

        LOG_DEBUG("FLUSHING I$");

        /**
         *  Invalidate (flush) I$
         *  mcr 15, 0, r0, cr7, cr5, {0}
         */
        retval = arm946e_write_cp15(target, 0x0f, 0x1);
        if (retval != ERROR_OK)
        {
                LOG_DEBUG("ERROR flushing I$");
                return retval;
        }

        return ERROR_OK;
}

int arm946e_post_debug_entry(struct target *target)
{
        uint32_t ctr_reg = 0x0;
        uint32_t retval = ERROR_OK;

        /* See if CACHES are enabled, and save that info
         * in the global vars, so that arm946e_pre_restore_context() can use them */
        arm946e_read_cp15(target, 0x02, (uint32_t *) &ctr_reg);
        dc = (ctr_reg >> 2) & 0x01;
        ic = (ctr_reg >> 12) & 0x01;

        if (arm946e_preserve_cache)
        {
                if (dc == 1)
                {
                        /* Clean and flush D$ */
                        arm946e_invalidate_whole_dcache(target);

                        /* Disable D$ */
                        ctr_reg &= ~(1 << 2);
                }

                if (ic == 1)
                {
                        /* Flush I$ */
                        arm946e_invalidate_whole_icache(target);

                        /* Disable I$ */
                        ctr_reg &= ~(1 << 12);
                }

                /* Write the new configuration */
                retval = arm946e_write_cp15(target, 0x02, ctr_reg);
                if (retval != ERROR_OK)
                {
                        LOG_DEBUG("ERROR disabling cache");
                        return retval;
                }
        } /* if preserve_cache */

        return ERROR_OK;
}

void arm946e_pre_restore_context(struct target *target)
{
        uint32_t ctr_reg = 0x0;
        uint32_t retval;

        if (arm946e_preserve_cache)
        {
                /* Get the contents of the CTR reg */
                arm946e_read_cp15(target, 0x02, (uint32_t *) &ctr_reg);

                /**
                 * Read-modify-write CP15 test state register
                 * to reenable I/D-cache linefills
                 */
                if (dc == 1)
                {
                        /* Enable D$ */
                        ctr_reg |= 1 << 2;
                }

                if (ic == 1)
                {
                        /* Enable I$ */
                        ctr_reg |= 1 << 12;
                }

                /* Write the new configuration */
                retval = arm946e_write_cp15(target, 0x02, ctr_reg);
                if (retval != ERROR_OK)
                {
                        LOG_DEBUG("ERROR enabling cache");
                }
        } /* if preserve_cache */
}

uint32_t arm946e_invalidate_dcache(struct target *target, uint32_t address,
                uint32_t size, uint32_t count)
{
        uint32_t csize = 0x0;
        uint32_t shift = 0;
        uint32_t cur_addr = 0x0;
        uint32_t cp15_idx, set, way, dtag;
        int nb_idx;
        uint32_t i = 0;
        int retval;

        for(i = 0; i < count*size; i++)
        {
                cur_addr = address + i;

                /* Get cache type */
                arm946e_read_cp15(target, 0x01, (uint32_t *) &csize);

                /* Conclude cache size to find number of lines */
                csize = (csize >> 18) & 0x0F;

                if (csize == 0)
                        shift = 0;
                else
                        shift = csize - 0x3; /* Now 0 = 4KB, 1 = 8KB, ... */

                csize = 1 << (12 + shift);
                nb_idx = (csize / 32);

                set = (cur_addr >> 5) & 0xff;   /* set field is 8 bits long */

                for (way = 0; way < NB_CACHE_WAYS; way++)
                {
                        /**
                         * Find if the affected address is kept in the cache.
                         * Because JTAG Scan Chain 15 offers limited approach,
                         * we have to loop through all cache ways (segments) and
                         * read cache tags, then compare them with with address.
                         */

                        /* Form and write cp15 index (segment + line idx) */
                        cp15_idx = way << 30 | set << 5;
                        retval = arm946e_write_cp15(target, 0x3a, cp15_idx);
                        if (retval != ERROR_OK)
                        {
                                LOG_DEBUG("ERROR writing index");
                                return retval;
                        }

                        /* Read dtag */
                        arm946e_read_cp15(target, 0x16, (uint32_t *) &dtag);

                        /* Check cache line VALID bit */
                        if ( !(dtag >> 4 & 0x1) )
                                continue;

                        /* If line is valid and corresponds to affected address - invalidate it */
                        if (dtag >> 5 == cur_addr >> 5)
                        {
                                /* Clean data cache line */
                                retval = arm946e_write_cp15(target, 0x35, 0x1);
                                if (retval != ERROR_OK)
                                {
                                        LOG_DEBUG("ERROR cleaning cache line");
                                        return retval;
                                }

                                /* Flush data cache line */
                                retval = arm946e_write_cp15(target, 0x1c, 0x1);
                                if (retval != ERROR_OK)
                                {
                                        LOG_DEBUG("ERROR flushing cache line");
                                        return retval;
                                }

                                break;
                        }
                } /* loop through all 4 ways */
        } /* loop through all addresses */

        return ERROR_OK;
}

uint32_t arm946e_invalidate_icache(struct target *target, uint32_t address,
                uint32_t size, uint32_t count)
{
        uint32_t cur_addr = 0x0;
        uint32_t cp15_idx, set, way, itag;
        uint32_t i = 0;
        int retval;

        for(i = 0; i < count*size; i++)
        {
                cur_addr = address + i;

                set = (cur_addr >> 5) & 0xff;   /* set field is 8 bits long */

                for (way = 0; way < NB_CACHE_WAYS; way++)
                {
                        /* Form and write cp15 index (segment + line idx) */
                        cp15_idx = way << 30 | set << 5;
                        retval = arm946e_write_cp15(target, 0x3a, cp15_idx);
                        if (retval != ERROR_OK)
                        {
                                LOG_DEBUG("ERROR writing index");
                                return retval;
                        }

                        /* Read itag */
                        arm946e_read_cp15(target, 0x17, (uint32_t *) &itag);

                        /* Check cache line VALID bit */
                        if ( !(itag >> 4 & 0x1) )
                                continue;

                        /* If line is valid and corresponds to affected address - invalidate it */
                        if (itag >> 5 == cur_addr >> 5)
                        {
                                /* Flush I$ line */
                                retval = arm946e_write_cp15(target, 0x1d, 0x0);
                                if (retval != ERROR_OK)
                                {
                                        LOG_DEBUG("ERROR flushing cache line");
                                        return retval;
                                }

                                break;
                        }
                } /* way loop */
        } /* addr loop */

        return ERROR_OK;
}

/** Writes a buffer, in the specified word size, with current MMU settings. */
int arm946e_write_memory(struct target *target, uint32_t address,
                uint32_t size, uint32_t count, const uint8_t *buffer)
{
        int retval;

        LOG_DEBUG("-");

        /* Invalidate D$ if it is ON */
        if (!arm946e_preserve_cache && dc == 1)
        {
                arm946e_invalidate_dcache(target, address, size, count);
        }

        /**
         * Write memory
         */
        if ( ( retval = arm7_9_write_memory(target, address,
                        size, count, buffer) ) != ERROR_OK )
        {
                return retval;
        }

        /* *
         * Invalidate I$ if it is ON.
         *
         * D$ has been cleaned and flushed before mem write thus forcing it to behave like write-through,
         * because arm7_9_write_memory() has seen non-valid bit in D$
         * and wrote data into physical RAM (without touching or allocating the cache line).
         * From ARM946ES Technical Reference Manual we can see that it uses "allocate on read-miss"
         * policy for both I$ and D$ (Chapter 3.2 and 3.3)
         *
         * Explanation :
         * "ARM system developer's guide: designing and optimizing system software" by
         * Andrew N. Sloss, Dominic Symes and Chris Wright,
         * Chapter 12.3.3 Allocating Policy on a Cache Miss :
         * A read allocate on cache miss policy allocates a cache line only during a read from main memory.
         * If the victim cache line contains valid data, then it is written to main memory before the cache line
         * is filled with new data.
         * Under this strategy, a write of new data to memory does not update the contents of the cache memory
         * unless a cache line was allocated on a previous read from main memory.
         * If the cache line contains valid data, then the write updates the cache and may update the main memory if
         * the cache write policy is write-through.
         * If the data is not in the cache, the controller writes to main memory only.
         */
        if (!arm946e_preserve_cache && ic == 1)
        {
                arm946e_invalidate_icache(target, address, size, count);
        }

        return ERROR_OK;

}

int arm946e_read_memory(struct target *target, uint32_t address,
                uint32_t size, uint32_t count, uint8_t *buffer)
{
        int retval;

        LOG_DEBUG("-");

        if ( ( retval = arm7_9_read_memory(target, address,
                        size, count, buffer) ) != ERROR_OK )
        {
                return retval;
        }

        return ERROR_OK;
}


COMMAND_HANDLER(arm946e_handle_cp15_command)
{
        int retval;
        struct target *target = get_current_target(CMD_CTX);
        struct arm946e_common *arm946e = target_to_arm946(target);

        retval = arm946e_verify_pointer(CMD_CTX, arm946e);
        if (retval != ERROR_OK)
                return retval;

        if (target->state != TARGET_HALTED)
        {
                command_print(CMD_CTX, "target must be stopped for \"%s\" command", CMD_NAME);
                return ERROR_OK;
        }

        /* one or more argument, access a single register (write if second argument is given */
        if (CMD_ARGC >= 1)
        {
                uint32_t address;
                COMMAND_PARSE_NUMBER(u32, CMD_ARGV[0], address);

                if (CMD_ARGC == 1)
                {
                        uint32_t value;
                        if ((retval = arm946e_read_cp15(target, address, &value)) != ERROR_OK)
                        {
                                command_print(CMD_CTX,
                                                "couldn't access reg %" PRIi32,
                                                address);
                                return ERROR_OK;
                        }
                        if ((retval = jtag_execute_queue()) != ERROR_OK)
                        {
                                return retval;
                        }

                        command_print(CMD_CTX, "%" PRIi32 ": %8.8" PRIx32,
                                        address, value);
                }
                else if (CMD_ARGC == 2)
                {
                        uint32_t value;
                        COMMAND_PARSE_NUMBER(u32, CMD_ARGV[1], value);
                        if ((retval = arm946e_write_cp15(target, address, value)) != ERROR_OK)
                        {
                                command_print(CMD_CTX,
                                                "couldn't access reg %" PRIi32,
                                                address);
                                return ERROR_OK;
                        }
                        command_print(CMD_CTX, "%" PRIi32 ": %8.8" PRIx32,
                                        address, value);
                }
        }

        return ERROR_OK;
}

static const struct command_registration arm946e_exec_command_handlers[] = {
        {
                .name = "cp15",
                .handler = arm946e_handle_cp15_command,
                .mode = COMMAND_EXEC,
                .usage = "regnum [value]",
                .help = "display/modify cp15 register",
        },
        COMMAND_REGISTRATION_DONE
};

const struct command_registration arm946e_command_handlers[] = {
        {
                .chain = arm9tdmi_command_handlers,
        },
        {
                .name = "arm946e",
                .mode = COMMAND_ANY,
                .help = "arm946e command group",
                .chain = arm946e_exec_command_handlers,
        },
        COMMAND_REGISTRATION_DONE
};

/** Holds methods for ARM946 targets. */
struct target_type arm946e_target =
{
        .name = "arm946e",

        .poll = arm7_9_poll,
        .arch_state = arm_arch_state,

        .target_request_data = arm7_9_target_request_data,

        .halt = arm7_9_halt,
        .resume = arm7_9_resume,
        .step = arm7_9_step,

        .assert_reset = arm7_9_assert_reset,
        .deassert_reset = arm7_9_deassert_reset,
        .soft_reset_halt = arm7_9_soft_reset_halt,

        .get_gdb_reg_list = arm_get_gdb_reg_list,

        //.read_memory = arm7_9_read_memory,
        //.write_memory = arm7_9_write_memory,
        .read_memory = arm946e_read_memory,
        .write_memory = arm946e_write_memory,

        .bulk_write_memory = arm7_9_bulk_write_memory,

        .checksum_memory = arm_checksum_memory,
        .blank_check_memory = arm_blank_check_memory,

        .run_algorithm = armv4_5_run_algorithm,

        .add_breakpoint = arm7_9_add_breakpoint,
        .remove_breakpoint = arm7_9_remove_breakpoint,
        //.add_breakpoint = arm946e_add_breakpoint,
        //.remove_breakpoint = arm946e_remove_breakpoint,

        .add_watchpoint = arm7_9_add_watchpoint,
        .remove_watchpoint = arm7_9_remove_watchpoint,

        .commands = arm946e_command_handlers,
        .target_create = arm946e_target_create,
        .init_target = arm9tdmi_init_target,
        .examine = arm7_9_examine,
        .check_reset = arm7_9_check_reset,
};