+/**
+ * Uses an on-chip algorithm for an ARM device to read from a NAND device and
+ * store the data into the host machine's memory.
+ *
+ * @param nand Pointer to the arm_nand_data struct that defines the I/O
+ * @param data Pointer to the data buffer to store the read data
+ * @param size Amount of data to be stored to the buffer.
+ * @return Success or failure of the operation
+ */
+int arm_nandread(struct arm_nand_data *nand, uint8_t *data, uint32_t size)
+{
+ struct target *target = nand->target;
+ struct armv4_5_algorithm algo;
+ struct arm *armv4_5 = target->arch_info;
+ struct reg_param reg_params[3];
+ uint32_t target_buf;
+ uint32_t exit = 0;
+ int retval;
+
+ /* Inputs:
+ * r0 buffer address
+ * r1 NAND data address (byte wide)
+ * r2 buffer length
+ */
+ static const uint32_t code[] = {
+ 0xe5d13000, /* s: ldrb r3, [r1] */
+ 0xe4c03001, /* strb r3, [r0], #1 */
+ 0xe2522001, /* subs r2, r2, #1 */
+ 0x1afffffb, /* bne s */
+
+ /* exit: ARMv4 needs hardware breakpoint */
+ 0xe1200070, /* e: bkpt #0 */
+ };
+
+ /* create the copy area if not yet available */
+ if (nand->op != ARM_NAND_READ || !nand->copy_area) {
+ retval = arm_code_to_working_area(target, code, sizeof(code),
+ nand->chunk_size, &nand->copy_area);
+ if (retval != ERROR_OK) {
+ return retval;
+ }
+ }
+
+ nand->op = ARM_NAND_READ;
+ target_buf = nand->copy_area->address + sizeof(code);
+
+ /* set up algorithm and parameters */
+ algo.common_magic = ARMV4_5_COMMON_MAGIC;
+ algo.core_mode = ARMV4_5_MODE_SVC;
+ algo.core_state = ARMV4_5_STATE_ARM;
+
+ init_reg_param(®_params[0], "r0", 32, PARAM_IN);
+ init_reg_param(®_params[1], "r1", 32, PARAM_IN);
+ init_reg_param(®_params[2], "r2", 32, PARAM_IN);
+
+ buf_set_u32(reg_params[0].value, 0, 32, target_buf);
+ buf_set_u32(reg_params[1].value, 0, 32, nand->data);
+ buf_set_u32(reg_params[2].value, 0, 32, size);
+
+ /* armv4 must exit using a hardware breakpoint */
+ if (armv4_5->is_armv4)
+ exit = nand->copy_area->address + sizeof(code) - 4;
+
+ /* use alg to write data from NAND chip to work area */
+ retval = target_run_algorithm(target, 0, NULL, 3, reg_params,
+ nand->copy_area->address, exit, 1000, &algo);
+ if (retval != ERROR_OK)
+ LOG_ERROR("error executing hosted NAND read");
+
+ destroy_reg_param(®_params[0]);
+ destroy_reg_param(®_params[1]);
+ destroy_reg_param(®_params[2]);
+
+ /* read from work area to the host's memory */
+ retval = target_read_buffer(target, target_buf, size, data);
+
+ return retval;
+}