src/flash/nand/arm_io.c

   1 /*
   2  * Copyright (C) 2009 by Marvell Semiconductors, Inc.
   3  * Written by Nicolas Pitre <nico at marvell.com>
   4  *
   5  * Copyright (C) 2009 by David Brownell
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the
  19  * Free Software Foundation, Inc.,
  20  * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  21  */
  22
  23 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include "arm_io.h"
  28 #include <target/armv4_5.h>
  29 #include <target/algorithm.h>
  30
  31 /**
  32  * Copies code to a working area.  This will allocate room for the code plus the
  33  * additional amount requested if the working area pointer is null.
  34  *
  35  * @param target Pointer to the target to copy code to
  36  * @param code Pointer to the code area to be copied
  37  * @param code_size Size of the code being copied
  38  * @param additional Size of the additional area to be allocated in addition to
  39  *                   code
  40  * @param area Pointer to a pointer to a working area to copy code to
  41  * @return Success or failure of the operation
  42  */
  43 int arm_code_to_working_area(struct target *target,
  44                 const uint32_t *code, unsigned code_size,
  45                 unsigned additional, struct working_area **area)
  46 {
  47         uint8_t code_buf[code_size];
  48         unsigned i;
  49         int retval;
  50         unsigned size = code_size + additional;
  51
  52         /* REVISIT this assumes size doesn't ever change.
  53          * That's usually correct; but there are boards with
  54          * both large and small page chips, where it won't be...
  55          */
  56
  57         /* make sure we have a working area */
  58         if (NULL == *area) {
  59                 retval = target_alloc_working_area(target, size, area);
  60                 if (retval != ERROR_OK) {
  61                         LOG_DEBUG("%s: no %d byte buffer", __FUNCTION__, (int) size);
  62                         return ERROR_NAND_NO_BUFFER;
  63                 }
  64         }
  65
  66         /* buffer code in target endianness */
  67         for (i = 0; i < code_size / 4; i++)
  68                 target_buffer_set_u32(target, code_buf + i * 4, code[i]);
  69
  70         /* copy code to work area */
  71         retval = target_write_memory(target, (*area)->address,
  72                         4, code_size / 4, code_buf);
  73
  74         return retval;
  75 }
  76
  77 /**
  78  * ARM-specific bulk write from buffer to address of 8-bit wide NAND.
  79  * For now this only supports ARMv4 and ARMv5 cores.
  80  *
  81  * Enhancements to target_run_algorithm() could enable:
  82  *   - ARMv6 and ARMv7 cores in ARM mode
  83  *
  84  * Different code fragments could handle:
  85  *   - Thumb2 cores like Cortex-M (needs different byteswapping)
  86  *   - 16-bit wide data (needs different setup too)
  87  *
  88  * @param nand Pointer to the arm_nand_data struct that defines the I/O
  89  * @param data Pointer to the data to be copied to flash
  90  * @param size Size of the data being copied
  91  * @return Success or failure of the operation
  92  */
  93 int arm_nandwrite(struct arm_nand_data *nand, uint8_t *data, int size)
  94 {
  95         struct target           *target = nand->target;
  96         struct arm_algorithm    algo;
  97         struct arm              *armv4_5 = target->arch_info;
  98         struct reg_param        reg_params[3];
  99         uint32_t                target_buf;
 100         uint32_t                exit = 0;
 101         int                     retval;
 102
 103         /* Inputs:
 104          *  r0  NAND data address (byte wide)
 105          *  r1  buffer address
 106          *  r2  buffer length
 107          */
 108         static const uint32_t code[] = {
 109                 0xe4d13001,     /* s: ldrb  r3, [r1], #1 */
 110                 0xe5c03000,     /*    strb  r3, [r0]     */
 111                 0xe2522001,     /*    subs  r2, r2, #1   */
 112                 0x1afffffb,     /*    bne   s            */
 113
 114                 /* exit: ARMv4 needs hardware breakpoint */
 115                 0xe1200070,     /* e: bkpt  #0           */
 116         };
 117
 118         if (nand->op != ARM_NAND_WRITE || !nand->copy_area) {
 119                 retval = arm_code_to_working_area(target, code, sizeof(code),
 120                                 nand->chunk_size, &nand->copy_area);
 121                 if (retval != ERROR_OK) {
 122                         return retval;
 123                 }
 124         }
 125
 126         nand->op = ARM_NAND_WRITE;
 127
 128         /* copy data to work area */
 129         target_buf = nand->copy_area->address + sizeof(code);
 130         retval = target_bulk_write_memory(target, target_buf, size / 4, data);
 131         if (retval == ERROR_OK && (size & 3) != 0)
 132                 retval = target_write_memory(target,
 133                                 target_buf + (size & ~3),
 134                                 1, size & 3, data + (size & ~3));
 135         if (retval != ERROR_OK)
 136                 return retval;
 137
 138         /* set up algorithm and parameters */
 139         algo.common_magic = ARM_COMMON_MAGIC;
 140         algo.core_mode = ARM_MODE_SVC;
 141         algo.core_state = ARM_STATE_ARM;
 142
 143         init_reg_param(&reg_params[0], "r0", 32, PARAM_IN);
 144         init_reg_param(&reg_params[1], "r1", 32, PARAM_IN);
 145         init_reg_param(&reg_params[2], "r2", 32, PARAM_IN);
 146
 147         buf_set_u32(reg_params[0].value, 0, 32, nand->data);
 148         buf_set_u32(reg_params[1].value, 0, 32, target_buf);
 149         buf_set_u32(reg_params[2].value, 0, 32, size);
 150
 151         /* armv4 must exit using a hardware breakpoint */
 152         if (armv4_5->is_armv4)
 153                 exit = nand->copy_area->address + sizeof(code) - 4;
 154
 155         /* use alg to write data from work area to NAND chip */
 156         retval = target_run_algorithm(target, 0, NULL, 3, reg_params,
 157                         nand->copy_area->address, exit, 1000, &algo);
 158         if (retval != ERROR_OK)
 159                 LOG_ERROR("error executing hosted NAND write");
 160
 161         destroy_reg_param(&reg_params[0]);
 162         destroy_reg_param(&reg_params[1]);
 163         destroy_reg_param(&reg_params[2]);
 164
 165         return retval;
 166 }
 167
 168 /**
 169  * Uses an on-chip algorithm for an ARM device to read from a NAND device and
 170  * store the data into the host machine's memory.
 171  *
 172  * @param nand Pointer to the arm_nand_data struct that defines the I/O
 173  * @param data Pointer to the data buffer to store the read data
 174  * @param size Amount of data to be stored to the buffer.
 175  * @return Success or failure of the operation
 176  */
 177 int arm_nandread(struct arm_nand_data *nand, uint8_t *data, uint32_t size)
 178 {
 179         struct target *target = nand->target;
 180         struct arm_algorithm algo;
 181         struct arm *armv4_5 = target->arch_info;
 182         struct reg_param reg_params[3];
 183         uint32_t target_buf;
 184         uint32_t exit = 0;
 185         int retval;
 186
 187         /* Inputs:
 188          *  r0  buffer address
 189          *  r1  NAND data address (byte wide)
 190          *  r2  buffer length
 191          */
 192         static const uint32_t code[] = {
 193                 0xe5d13000,     /* s: ldrb  r3, [r1]     */
 194                 0xe4c03001,     /*    strb  r3, [r0], #1 */
 195                 0xe2522001,     /*    subs  r2, r2, #1   */
 196                 0x1afffffb,     /*    bne   s            */
 197
 198                 /* exit: ARMv4 needs hardware breakpoint */
 199                 0xe1200070,     /* e: bkpt  #0           */
 200         };
 201
 202         /* create the copy area if not yet available */
 203         if (nand->op != ARM_NAND_READ || !nand->copy_area) {
 204                 retval = arm_code_to_working_area(target, code, sizeof(code),
 205                                 nand->chunk_size, &nand->copy_area);
 206                 if (retval != ERROR_OK) {
 207                         return retval;
 208                 }
 209         }
 210
 211         nand->op = ARM_NAND_READ;
 212         target_buf = nand->copy_area->address + sizeof(code);
 213
 214         /* set up algorithm and parameters */
 215         algo.common_magic = ARM_COMMON_MAGIC;
 216         algo.core_mode = ARM_MODE_SVC;
 217         algo.core_state = ARM_STATE_ARM;
 218
 219         init_reg_param(&reg_params[0], "r0", 32, PARAM_IN);
 220         init_reg_param(&reg_params[1], "r1", 32, PARAM_IN);
 221         init_reg_param(&reg_params[2], "r2", 32, PARAM_IN);
 222
 223         buf_set_u32(reg_params[0].value, 0, 32, target_buf);
 224         buf_set_u32(reg_params[1].value, 0, 32, nand->data);
 225         buf_set_u32(reg_params[2].value, 0, 32, size);
 226
 227         /* armv4 must exit using a hardware breakpoint */
 228         if (armv4_5->is_armv4)
 229                 exit = nand->copy_area->address + sizeof(code) - 4;
 230
 231         /* use alg to write data from NAND chip to work area */
 232         retval = target_run_algorithm(target, 0, NULL, 3, reg_params,
 233                         nand->copy_area->address, exit, 1000, &algo);
 234         if (retval != ERROR_OK)
 235                 LOG_ERROR("error executing hosted NAND read");
 236
 237         destroy_reg_param(&reg_params[0]);
 238         destroy_reg_param(&reg_params[1]);
 239         destroy_reg_param(&reg_params[2]);
 240
 241         /* read from work area to the host's memory */
 242         retval = target_read_buffer(target, target_buf, size, data);
 243
 244         return retval;
 245 }
 246