UIM卡上电需要满足下面的时序。
    
                                 UIM上电时序                                                          UIM下电时序

MSM8909平台UIM初始化流程如下。

在initialize_intctrl中设置了UART接收数据的中断服务程序为uimIntctrlIsr，当UART的DATA数据线为接收模式时，一旦DATA线上面有数据，uimIntctrlIsr函数就会被调用。/* Initialize interrupt controller */ void initialize_intctrl(uim_instance_global_type *uim_ptr) { . . . . . . DalInterruptController_RegisterISR(uim_hw_if.intctrl[uim_instance].m_IntCtrl_handle_ptr, uim_hw_if.intctrl[uim_instance].m_uartIRQNum, (DALISR) uimIntctrlIsr,// 设置UART接收中断服务函数 (const DALIRQCtx) uim_ptr, DALINTRCTRL_ENABLE_LEVEL_HIGH_TRIGGER); . . . . . . } /* initialize_intctrl */ 在uim_initialize_state中，设置UIM的当前工作电压为1.8V，UIM支持的最大电压为3V。void uim_initialize_state ( uim_instance_global_type *uim_ptr ) { /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ /* Initialize the uim Rx character ISR processing state. */ uim_ptr->rxtx_state_machine.rx_state = UIM_RX_PROCESS_IDLE; if (uim_ptr->hardware.uim_ldo.customize_ldo_setting && uim_ptr->hardware.uim_ldo.desired_voltage_class != UIM_VOLTAGE_CLASS_INVALID) { /* Set the UIM interface voltage to desired voltage class */ uim_ptr->state.current_voltage_class = uim_ptr->hardware.uim_ldo.desired_voltage_class; uim_ptr->state.max_possible_voltage_class = uim_ptr->hardware.uim_ldo.desired_voltage_class; } else { /* Set the UIM interface voltage to the minimum voltage class */ // 设置UIM的当前电源电压为1.8V uim_ptr->state.current_voltage_class = UIM_VOLTAGE_CLASS_C; // 设置UIM支持的最大电压为3V uim_ptr->state.max_possible_voltage_class = UIM_VOLTAGE_CLASS_B; } } /* uim_initialize_state */UIM_VOLTAGE_CLASS_C和UIM_VOLTAGE_CLASS_B在modem_procuimuimdrvsrcuimdrv.h中定义。
/* The enum type describes the voltage classes supported on the UIM interface. The list must start at the lowest voltage and progress top the highest voltage in order. */ typedef enum { UIM_VOLTAGE_CLASS_INVALID, UIM_VOLTAGE_CLASS_C, /* Use 1.8 volts */ UIM_VOLTAGE_CLASS_B, /* Use 3 volts */ } uim_voltage_class_type;SET_UIM_BAUD_RATE_SLOT函数用来设置UART通信的波特率，该函数在modem_procuimuimdrvsrchwclkregimeuimdrv_clk.c中定义。void SET_UIM_BAUD_RATE_SLOT ( uim_instance_enum_type uim_instance, uim_clock_rate_conversion_factor_type nFI, uim_baud_rate_adjustment_factor_type nDI ) { uim_instance_global_type *uim_ptr = uim_get_instance_ptr(uim_instance); if(uim_ptr == NULL) { UIM_MSG_ERR_0("SET_UIM_BAUD_RATE_SLOT: uim_ptr is NULL"); return; } /* Store the current FI and DI */ // 设置FI参数 uim_ptr->state.FI_current = nFI; // 设置DI参数 uim_ptr->state.DI_current = nDI; setBaudRate(uim_ptr->id, nFI, nDI); return; } /* SET_UIM_BAUD_RATE_SLOT */UART波特率的计算方法：CLK / (FI / DI)，CLK一般输出为3.84MHZ或者4.8MHZ，本例中SET_UIM_BAUD_RATE_SLOT传入的参数分别是UIM_CRCF_372_1和UIM_BRAF_1。
/* Set the UART clock to the default values. */ SET_UIM_BAUD_RATE_SLOT ( uim_ptr->id, UIM_CRCF_372_1, UIM_BRAF_1);UART的波特率等于3840000 / (372 / 1) = 10323。这个是大部分UIM卡的速率，叫做一倍速卡，还有一种4倍速的卡，波特率等于3840000 / (372 / 4) = 41290，高通平台目前支持一倍速的卡。uim_dev_init中设置的波特率在后面给UIM卡复位的时候会再次被更改，后面会提到。UIM上电流程如下。

进入uim_reset_uim函数分析
void uim_reset_uim ( rex_sigs_type *mask, boolean me_powerup, uim_instance_global_type *uim_ptr ) { . . . . . . /* Indicate that we did not receive the ATR */ uim_ptr->atr.atr_received = FALSE; /* reset the voltage_class_known_from_atr varialbe */ uim_ptr->flag.voltage_class_known_from_atr = FALSE; if (me_powerup) { . . . . . . /* command to power up the UIM due to task start up */ if (uim_ptr->command.static_cmd_buf.hdr.command == UIM_HOTSWAP_CARD_INS_F) { UIMDRV_MSG_LOW_1(uim_ptr->id,"HOTSWAP: uim_reset_uim due to card inserted command for slot 0x%x", uim_ptr->command.static_cmd_buf.hdr.slot); } uim_ptr->command.static_cmd_buf.hdr.command = UIM_INTERNAL_ME_PUP_F; } else { . . . . . . } uim_process_command(mask, uim_ptr); } /* uim_reset_uim() */uim_ptr->command.static_cmd_buf.hdr.command = UIM_INTERNAL_ME_PUP_F;设置状态机的初始状态。UIM_INTERNAL_ME_PUP_F是一个宏，值为0x0100，在modem_procuimapiuim_v.h中定义：/* Command types */ typedef enum { UIM_NO_SUCH_COMMAND_F = 0, /* No such command */ UIM_INTERNAL_ME_PUP_F = 0x0100,/* POWER UP UIM due to task start up */ UIM_INTERNAL_WAKE_UP_F, /* Power up due to Power management */ . . . . . . UIM_MAX_F } uim_cmd_name_type;接下来调用uim_process_command函数：
void uim_process_command ( /* Pointer to received command */ rex_sigs_type *mask, /* rex signals type mask */ uim_instance_global_type *uim_ptr ) { . . . . . . /* If the current directory is current to process the command, then process the command */ if(FALSE == intermediate_select.is_needed) { . . . . . . /* Get the mode of the command */ uim_ptr->state.cmd_mode = (uim_command_mode_type) UIM_GET_CMD_MODE((int)uim_ptr->command.cmd_ptr->hdr.command); switch (uim_ptr->state.cmd_mode) { . . . . . . case UIM_GENERIC_CMD: default: command_transacted = uim_process_generic_command (uim_ptr); break; } /* end for switch */ } else { . . . . . . } . . . . . . } /* uim_process_command */UIM_GET_CMD_MODE是一个宏，在modem_procuimuimdrvsrcuim.c中定义：
#define UIM_GET_CMD_MODE(command) ((command >> 8) & 0x0F)
uim_ptr->command.cmd_ptr->hdr.command在前面被赋值为0x0100，这样uim_ptr->state.cmd_mode的值就是0x01，在switch中会走UIM_GENERIC_CMD分支。UIM_GENERIC_CMD是一个宏，在modem_procuimuimdrvsrcuimi.h中定义：typedef enum { UIM_NO_SUCH_CMD = 0x0, UIM_GENERIC_CMD = 0x1, UIM_GSM_CMD = 0x2, UIM_CDMA_CMD = 0x3, UIM_USIM_CMD = 0x4, UIM_ISIM_CMD = 0x5 } uim_command_mode_type;接下来进入uim_process_generic_command函数：boolean uim_process_generic_command ( uim_instance_global_type *uim_ptr ) { . . . . . . /* Process the generic command. */ switch (uim_ptr->command.cmd_ptr->hdr.command) { case UIM_INTERNAL_ME_PUP_F: /* POWER UP UIM due to task start up */ uim_ptr->command.generic_state_ptr = UIM_INTERNAL_PUP_STATES; break; . . . . . . } if (status) { /* Call the state machine. */ uim_generic_command (uim_ptr); } else { . . . . . . } return(status); } /* uim_process_generic_command() */uim_ptr->command.cmd_ptr->hdr.command在前面被赋值为UIM_INTERNAL_ME_PUP_F，所以在switch中会走UIM_INTERNAL_ME_PUP_F分支。在这个case分支中，执行了让uim_ptr->command.generic_state_ptr 指针指向了UIM_INTERNAL_PUP_STATES数组，该数组在modem_procuimuimdrvsrcuimgen.c中定义：/* State configuration for the commands. */ /* UIM_INTERNAL_ME_PUP_F = 0x0100, POWER UP UIM due to task start up */ static const uim_generic_state_type UIM_INTERNAL_PUP_STATES[] = { UIM_POWER_UP_ST, UIM_RESET_ST, UIM_DELAY_AFTER_ATR_ST, UIM_PPS_ST, UIM_UPDATE_OP_PARAMS_ST, #if defined( FEATURE_UIM_T_1_SUPPORT ) UIM_IFS_NEG_ST, #endif /* FEATURE_UIM_T_1_SUPPORT */ UIM_SEND_STATUS_ST, UIM_CHECK_CHARACTERISTICS_ST, UIM_TERMINAL_CAPABILITY_ST, UIM_SELECT_ICCID_ST, UIM_READ_ICCID_ST, UIM_CHECK_FOR_CDMA_DF, UIM_DONE_ST };后面会通过对generic_state_ptr指针的操作来进行状态机的切换。接下来调用uim_generic_command函数。void uim_generic_command ( uim_instance_global_type *uim_ptr ) { . . . . . . /* Build an APDU based on the UIM generic state */ switch(*uim_ptr->command.generic_state_ptr) { . . . . . . case UIM_POWER_UP_ST: /* Power Up state */ { . . . . . . uim_power_up(uim_ptr); . . . . . . if(uim_nv_is_feature_enabled(UIMDRV_FEATURE_INTERFACE_NOT_USED, uim_ptr) == FALSE) { uim_timed_sleep(UIM_CARD_DELAY_TIMEOUT, uim_ptr, UIM_ALL_ZERO_SIG); (void)rex_set_sigs(uim_ptr->tcb_ptr, UIM_CMD_RSP_SIG); } } /* end case - UIM_POWER_UP_ST */ break; case UIM_RESET_ST: /* Reset State */ { /* Indicate that we have not yet received an ATR */ uim_ptr->atr.atr_received = FALSE; . . . . . . /* Set the flag to FALSE */ uim_ptr->atr.atr_pps_done= FALSE; uim_ptr->flag.invalid_pps_received = FALSE; . . . . . . /* Reset the UIM card */ uim_reset( &uim_ptr->command.rsp_buf, uim_ptr); . . . . . . } /* end case - UIM_RESET_ST */ break; case UIM_DELAY_AFTER_ATR_ST: /* Introduce delay after ATR */ { uim_timed_sleep(UIM_DELAY_TIME_AFTER_ATR, uim_ptr, UIM_ALL_ZERO_SIG); (void)rex_set_sigs(uim_ptr->tcb_ptr,UIM_CMD_RSP_SIG); } break; case UIM_PPS_ST: /* PPS State */ { . . . . . . uim_send_pps(&uim_ptr->atr.pps_req_buf, uim_ptr); } /* end case - UIM_PPS_ST */ break; case UIM_UPDATE_OP_PARAMS_ST: /* Update Operational Parameters State */ { /* Fill out the operational parameters as default values */ uim_ptr->state.op_params_buf.change_baud_rate = TRUE; uim_ptr->state.op_params_buf.change_clk_freq = TRUE; uim_ptr->state.op_params_buf.change_guardtime = TRUE; uim_ptr->state.op_params_buf.FI = UIM_CRCF_372_1; uim_ptr->state.op_params_buf.DI = UIM_BRAF_1; if (uim_hw_if.clkreg[uim_ptr->id].m_simClkFreq == uim_clock_frequency[UIMDRV_CLK_FREQ_3_84_MHZ]) { uim_ptr->state.op_params_buf.clock_frequency = UIMDRV_CLK_FREQ_3_84_MHZ; } else if(uim_hw_if.clkreg[uim_ptr->id].m_simClkFreq == uim_clock_frequency[UIMDRV_CLK_FREQ_4_8_MHZ]) { uim_ptr->state.op_params_buf.clock_frequency = UIMDRV_CLK_FREQ_4_8_MHZ; } /* Determine if there is an interface byte to process. This code operates on the ATR as well as the PPS response. */ if (uim_ptr->command.rsp_buf.rsp.data[UIM_ATR_T0_BYTE] & (UIM_ATR_TA_PRESENT)) { /* Set the op parameters from the ATR/PPS response */ uim_ptr->state.op_params_buf.FI = (uim_clock_rate_conversion_factor_type) (uim_ptr->command.rsp_buf.rsp.data[UIM_TA1_INDEX] >> UIM_FI_SHIFT_OF_TA1); uim_ptr->state.op_params_buf.DI = (uim_baud_rate_adjustment_factor_type) (uim_ptr->command.rsp_buf.rsp.data[UIM_TA1_INDEX] & UIM_DI_MASK_OF_TA1); } /* end if - TA(1) does exist in the ATR/PPS. */ . . . . . . /* Send the operational parameters */ uim_update_op_params( &uim_ptr->state.op_params_buf, uim_ptr); . . . . . . /* Signal is set internally for proper operation of state machine */ uim_timed_sleep(UIM_CARD_DELAY_TIMEOUT, uim_ptr, UIM_ALL_ZERO_SIG); (void)rex_set_sigs(uim_ptr->tcb_ptr, UIM_CMD_RSP_SIG); } /* end case - UIM_UPDATE_OP_PARAMS_ST */ break; . . . . . . } /* end of main switch */ } /* uim_generic_command */uim_ptr->command.generic_state_ptr在前面指向了UIM_INTERNAL_PUP_STATES数组，该数组的第一个元素是UIM_POWER_UP_ST，所以在switch中，会走UIM_POWER_UP_ST分支。在这个case中，最后会调用uim_power_up函数。void uim_power_up ( uim_instance_global_type *uim_ptr ) { . . . . . . /* Program the currently selected voltage */ switch (uim_ptr->state.current_voltage_class) { case UIM_VOLTAGE_CLASS_C: { UIMDRV_MSG_HIGH_0(uim_ptr->id, "uim power up @ 1.8 v"); uim_program_voltage_class( uim_ptr, UIM_VOLTAGE_CLASS_C ); } /* end case - UIM_VOLTAGE_1_8_V */ break; case UIM_VOLTAGE_CLASS_B: { UIMDRV_MSG_HIGH_0(uim_ptr->id, "uim power up @ 3 v"); uim_program_voltage_class( uim_ptr, UIM_VOLTAGE_CLASS_B ); } /* end case - UIM_VOLTAGE_3V */ break; default: { UIMDRV_MSG_HIGH_0(uim_ptr->id, "uim power up @ unknown voltage"); return; } } /* Turn on the clock for the R-UIM interface */ UIM_TCXO_MUST_BE_ON_SLOT(uim_ptr); /* Print the configuration before changing the state */ uim_print_uim_config(uim_ptr); /* First, turn on the UIM LDO. */ uim_power_on_ldo_slot(uim_ptr); /* Next, place the I/O line in reception mode. */ UIM_STOP_BREAK_SLOT(uim_ptr); UIM_CONFIGURE_DATA_FOR_UIM_CONTROLLER(uim_ptr); uim_clk_busy_wait(500); uim_uartdm_uim_controller_recover(uim_ptr); uim_clk_busy_wait(200); UIM_CONFIGURE_CLK_FOR_UIM_CONTROLLER(uim_ptr); uim_clk_busy_wait(200); /* Setup the UIM clock based on clock frequency set by HW enumeration */ if (uim_hw_if.clkreg[uim_ptr->id].m_simClkFreq == uim_clock_frequency[UIMDRV_CLK_FREQ_3_84_MHZ]) { uim_clock_control (uim_ptr->id, UIMDRV_CLK_FREQ_3_84_MHZ); } else if(uim_hw_if.clkreg[uim_ptr->id].m_simClkFreq == uim_clock_frequency[UIMDRV_CLK_FREQ_4_8_MHZ]) { uim_clock_control (uim_ptr->id, UIMDRV_CLK_FREQ_4_8_MHZ); } /* Reset the receiver so that the receiver does not process the stop break as a received byte */ UIM_RESET_RX_SLOT (uim_ptr); } /* uim_power_up */该函数中，首先根据uim_ptr->state.current_voltage_class的值来进行UIM电源的配置，该值在前面被赋值为UIM_VOLTAGE_CLASS_C，即1.8V。接下来将DATA线设置为接收模式，最后打开UIM的电源，配置CLK线输出3.84MHZ的时钟。注意，uim_power_up中并没有拉高RST线。
uim_generic_command调用完uim_power_up后，通过rex_set_sigs发送UIM_CMD_RSP_SIG信号。返回到uim_task_common函数，在调用完uim_start_initial_powerup后，uim_task_common会进入for循环。void uim_task_common ( dword uim_global_ptr ) { . . . . . . uim_dev_init(uim_ptr); . . . . . . /* Power up/reset the card */ uim_start_initial_powerup(uim_ptr, &i_mask); . . . . . . for (;;) { /* Never exit this loop... */ /* Perform the rex wait or check the q and set the signal mask */ rex_signals_mask = get_rex_sigs_mask(uim_ptr, i_mask); #ifdef FEATURE_UIM_TEST_FRAMEWORK #error code not present #endif /* FEATURE_UIM_TEST_FRAMEWORK */ /* Handle the signals that are set */ b_goto_top = uim_signal_handler(&rex_signals_mask, &i_mask, uim_ptr); . . . . . . } /* end for (;;) */ } /* end uim_task */该循环会阻塞等待信号，一旦有信号发送，相应的函数就会被调用，信号和函数的对应关系在modem_procuimuimdrvsrcuim_sigs.c中。/* This table associates each UIM signal to its appropriate handler function */ static uim_sig_map_type uim_sig_map[] = { {UIM_DOG_HB_RPT_SIG, uim_handle_dog_sig}, {UIM_TASK_STOP_SIG, uim_handle_task_stop_sig}, {UIM_SUSPICIOUS_CARD_REM_SIG,uim_handle_card_removed_suspicious_sig}, {UIM_POLL_TIMER_SIG, uim_handle_poll_timer_sig}, {UIM_HOTSWAP_CMD_CARD_REM_SIG, uim_handle_card_removed_sig}, {UIM_HOTSWAP_CMD_CARD_INS_SIG, uim_handle_card_inserted_sig}, #ifdef FEATURE_UIM_USB_UICC {UIM_USB_FALLBACK_TO_ISO_SIG, uim_handle_usb_fallback_to_iso_sig}, {UIM_USB_REMOTE_WAKEUP_SIG, uim_handle_usb_remote_wakeup_sig}, #endif /* FEATURE_UIM_USB_UICC */ {UIM_STATE_TOGGLE_SIG, uim_handle_state_toggle_sig}, {UIM_FETCH_PENDING_SIG, uim_handle_fetch_pending_sig}, {UIM_CMD_Q_SIG, uim_handle_cmd_q_sig}, {UIM_CMD_RSP_SIG, uim_handle_cmd_rsp_sig}, {UIM_EFSLOG_PURGE_SIG, uim_handle_efslog_purge_sig}, {UIM_CMD_RSP_TIMEOUT_SIG, uim_handle_cmd_rsp_timeout_sig}, {UIM_TRANSACTION_SIG, uim_handle_cmd_rsp_timeout_sig}, {UIM_SIMULATE_NULL_TIMER_EXP_SIG, uim_handle_simulate_null_timer_exp_sig}, {UIM_BUSY_IND_TIMER_EXP_SIG, uim_handle_busy_ind_timer_exp_sig}, {UIM_TRANS_TIMER_EXP_SIG, uim_handle_trans_timer_exp_sig}, {UIM_MCGF_NV_REFRESH_SIG, uim_handle_mcgf_nv_refresh_sig}, {UIM_EXT_RECOVERY_TIMER_EXP_SIG, uim_handle_extended_recovery_timer_exp_sig}, };前面说过，uim_generic_command调用完uim_power_up后，通过rex_set_sigs发送UIM_CMD_RSP_SIG信号。在uim_sig_map数组中，UIM_CMD_RSP_SIG信号对应得处理函数是uim_handle_cmd_rsp_sig，该函数调用的流程如下。
进入uim_generic_command_response函数分析。
uim_cmd_status_type uim_generic_command_response ( uim_rsp_buf_type *rsp_ptr, uim_instance_global_type *uim_ptr ) { . . . . . . /* Necessary so that we do not change the uim state and switch into that case also */ curr_uim_generic_state = *uim_ptr->command.generic_state_ptr; UIMDRV_MSG_HIGH_1(uim_ptr->id,"Processsing uim_generic_command_response for state 0x%x", curr_uim_generic_state); switch (curr_uim_generic_state) { . . . . . . case UIM_POWER_UP_ST: /* Power Up state */ { /* Get the next state. */ ++uim_ptr->command.generic_state_ptr; } /* end case - UIM_POWER_UP_ST */ break; . . . . . . } /* end switch - curr_uim_generic_state */ /* Continue processing the command only if the response indicates success. */ if (status == UIM_CMD_SUCCESS) { /* Process the next state of this command. */ uim_generic_command(uim_ptr); } /* end if - command is still in progress */ . . . . . return(status); } /* uim_generic_command_response */在switch中，会走UIM_POWER_UP_ST分支。在这个case中，只是让uim_ptr->command.generic_state_ptr指针指向UIM_INTERNAL_PUP_STATES数组的下一项。所以uim_ptr->command.generic_state_ptr指针指向的值等于UIM_RESET_ST。然后调用uim_generic_command函数，该函数在前面介绍过。uim_generic_command执行到switch时，会走UIM_RESET_ST分支，于是uim_reset被调用。
void uim_reset ( uim_rsp_buf_type *rsp_ptr, /* Defines where to put the ATR */ uim_instance_global_type *uim_ptr ) { . . . . . . /* Assert the reset line */ UIM_ASSERT_RESET_SLOT (uim_ptr); /* Enable the UART transmitter */ UIM_ENABLE_UART_TX_SLOT (uim_ptr); /* Enable the UART receiver */ UIM_ENABLE_UART_RX_SLOT (uim_ptr); . . . . . . /* Set the UART clock to the default values. */ SET_UIM_BAUD_RATE_SLOT ( uim_ptr->id, UIM_CRCF_372_1, UIM_BRAF_1); . . . . . . /* De-assert the reset line */ UIM_DEASSERT_RESET_SLOT (uim_ptr); . . . . . if(uim_nv_is_feature_enabled(UIMDRV_FEATURE_HANDLE_NO_ATR_IN_40000_CLK_CYCLES, uim_ptr) == TRUE) { . . . . . . } else { if((uim_ptr->state.DI_current < UIM_BRAF_SIZE) && (uim_ptr->state.FI_current < UIM_CRCF_SIZE)) { uim_uartdm_set_wwt_val(uim_ptr, uim_ptr->card_cmd.work_waiting_time_etus); uim_start_cmd_rsp_timer( uim_ptr->card_cmd.work_waiting_time + UIM_UART_DM_WAITING_TIME_CORRECTION, uim_ptr); } else { . . . . . . } } } /* uim_reset */重点来了，uim_reset会调用SET_UIM_BAUD_RATE_SLOT ( uim_ptr->id, UIM_CRCF_372_1, UIM_BRAF_1);重新设置波特率为一倍速，所以不管前面的uim_dev_init函数设置波特率为多少，uim_reset会重置波特率。随后通过UIM_DEASSERT_RESET_SLOT (uim_ptr);来拉高RST线，UIM卡在检测到RST线被高后，会发送ATR给到DATA线。uim_reset的最后会开启定时器，如果定时器超时，那么会发送UIM_CMD_RSP_TIMEOUT_SIG信号，uim_handle_cmd_rsp_timeout_sig函数就会被调用。如果UIM卡在定时时间内发送了ATR，那么uimIntctrlIsr函数就会被调用。
uim_read_rx_fifo会读取DATA线上的数据，保存早uim_ptr->card_cmd.uart_rx_buf中。
void uim_read_rx_fifo ( uim_instance_global_type *uim_ptr, dword isr, dword *no_of_bytes_received_ptr ) { int length; dword uart_status; int i=0; if(isr == MSMU_ISR_RXSTALE) { *no_of_bytes_received_ptr = UIM_GET_NUM_BYTES_IN_RX_SLOT(uim_ptr) - uim_ptr->card_cmd.total_bytes_read; } if (isr == MSMU_ISR_RXLEV) { *no_of_bytes_received_ptr = (4 * MSMU_DEF_RFWR_VAL); } if (*no_of_bytes_received_ptr % 4) { length = (*no_of_bytes_received_ptr/4) + 1; } else { length = *no_of_bytes_received_ptr/4; } for(uart_status = UIM_READ_STATUS_SLOT(uim_ptr); ((uart_status & MSMU_SR_RXRDY) && (length > 0)) ; length--) { uim_ptr->card_cmd.uart_rx_buf[i++] = UIM_GET_RX_WORD_SLOT(uim_ptr); } uim_ptr->card_cmd.total_bytes_read += *no_of_bytes_received_ptr; return; } /* end uim_read_rx_fifo */uim_rx_isr_receive_atr会解析ATR中TS，T0等参数，最后会调用uim_command_response_callback来清除定时器，这样定时器就不会发送超时信号。
void uim_command_response_callback ( uim_instance_global_type *uim_ptr ) { /*if it is a bad status word and Feature is enabled trigger recovery*/ if(TRUE == uim_nv_is_feature_enabled(UIMDRV_FEATURE_RECOVERY_ON_BAD_STATUS_WORD, uim_ptr) && TRUE == uim_ptr->flag.bad_status_words_error) { UIMDRV_MSG_ERR_0(uim_ptr->id,"recieved bad status word. forcing recovery"); uim_force_recovery(uim_ptr); return; } /* set the command response signal */ UIMDRV_MSG_LOW_0(uim_ptr->id,"Recd Command Response Signal"); uim_clear_cmd_rsp_timer(uim_ptr); /* clear the signal as well just in case if it was set */ (void) rex_clr_sigs( uim_ptr->tcb_ptr, UIM_TRANSACTION_SIG ); (void) rex_set_sigs( uim_ptr->tcb_ptr, UIM_CMD_RSP_SIG ); } /* uim_command_response_callback */