Receive Queue, Rx Queue Flow Chart | Texas Instruments TMS320DM357

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USB Controller Host and Peripheral Modes Operation

3.3.2.4Receive Queue

Figure 15 shows an Rx Queue. Rx queue provide a logical queue of processor memory space for DMA packets to be received from DMA controller channel. Each channel has single Rx queue. There are no multiple queue as in transmit channels. Each queue has one associated Rx Queue Head Descriptor Pointer and one associated Rx Completion Pointer contained in the channel Rx DMA State. The Rx queue are linked lists of Rx buffer descriptors that constitute processor memory space for one or more packets to be received. Packet space is added to the tail of the list by the software and received packets are freed from the list by the DMA controller as each packet is received.

Figure 15. Rx Queue Flow Chart

SOP descriptor

Descriptor

Descriptor

Descriptor

EOP descriptor

Buffer

Buffer

Buffer

Buffer

Buffer

Rx queue head descriptor pointer

3.3.2.5Operation

∙After reset the software must write zeroes to all Rx DMA State registers (RCPPIDMASTATEW0, RCPPIDMASTATEW1, RCPPIDMASTATEW2, RCPPIDMASTATEW3, RCPPIDMASTATEW4, RCPPIDMASTATEW5 and RCPPIDMASTATEW6).

∙The software constructs receive queue in memory.

∙Enable DMA for the endpoint in the PERI_RXCSR or HOST_RXCSR by setting the DMAEN bit.

∙Enable the DMA ports by setting RCPPI_ENABLE bit of RCPPICR register.

∙Set the value in RBUFCNTn register (where n is the channel number) for the number of buffers available in the Rx queue. The hardware requires at least 3 available buffers to start the DMA. A new transfer will not be started if the buffer count is below 3. The value in RBUFCNTn decrements as DMA controller consumes the buffers for reception.

∙Write the head of the queue descriptor pointer to the RCPPIDMASTATEW1 register to start the DMA.

∙The USB controller will send IN token and wait for the data on the bus. Once data is received, DMA controller will transfer the data in the Rx queue from the endpoint FIFO. Once a complete DMA packet is received, interrupt associated with the DMA channel is asserted.

SPRUGH3–November 2008

Universal Serial Bus (USB) Controller

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Texas Instruments TMS320DM357 manual Receive Queue, Rx Queue Flow Chart

Contents

Users Guide Submit Documentation Feedback Contents 100 Appendix a Type Register Host mode only HOSTTYPE0 List of Figures Receive Cppi DMA State Word 1 RCPPIDMASTATEW1 List of Tables Function Address Register Faddr Field Descriptions Document Revision History Related Documentation From Texas Instruments Read This First Notational Conventions Notational Conventions Purpose of the Peripheral FeaturesFeatures Not Supported Cppi Functional Block Diagram Example 1. Initializing the USB Controller Supported Use Case Examples Example 2. Programming the USB Endpoints in Peripheral Mode Example 3. Programming the USB Endpoints in Host Mode Else Example 4. Programming the USB DMA Controller While usbRegs-PERITXCSR Industry Standards Compliance Statement USB Pins Signal DescriptionsClock Control Indexed and Non-Indexed Registers Dynamic Fifo Sizing USB PHY Initialization Interrupt Service Routine Flow Chart Peripheral Mode Control Transactions USB Controller Peripheral Mode Operation Write Requests Zero Data Requests Read Requests Endpoint 0 States CPU Actions at Transfer Phases OUT Sequence of Transfer Endpoint 0 Service Routine = Idle Service Endpoint 0 Flow Chart Idle Mode Flow Chart Idle Mode TX Mode Flow Chart TX Mode RX Mode Flow Chart RX Mode Additional Conditions Error Handling Setup Peripheral Mode Bulk In TransactionsBit Position Bit Field Name Configuration Bulk Transactions Operation Peripheral Mode Bulk OUT Transactions Disnyet Interrupt Transactions Isochronous in Transactions Isochronous Transactions Isochronous OUT Transactions Set to 1 to enable isochronous protocol Host Mode Control Transactions USB Controller Host Mode Operation Setup Phase of a Control Transaction Flow Chart Setup Phase Rxpktrdy Data Phase OUT Data Phase Data Phase Flow Chart OUT Data Phase Flow Chart Completion of Setup or OUT Data Phase Flow Chart Status Phase following Setup Phase or OUT Data Phase OUT Status Phase following in Data Phase Completion of in Data Phase Flow Chart Host Mode Bulk in Transactions Bulk OUT Transactions Host Mode Interrupt Transactions Host Mode Isochronous in Transactions Host Mode Isochronous Out Transactions DMA Transmit Operation DMA OperationTransmit Buffer Cppi Transmit Buffer Descriptor Bits Name Description Transmit Buffer Descriptor WordBits Name Description 310 Buffer Pointer Descriptor. The software sets the Buffer Pointer EOQ Transmit DMA State Operation Transmit Queue Transparent Mode and Rndis Mode Transmit DMA Operation Transparent Mode Setup Rndis Mode SetupDMA Channel TearDown DMA Receive Operation Receive Buffer Descriptor Word Cppi Receive Buffer Descriptor Bit Field Receive DMA State Receive Queue Rx Queue Flow Chart USB Controller Host and Peripheral Modes Operation Receive Abort Handling Rndis Mode and Transparent Mode Receive DMA Operation Interrupt Handling DMA Teardown ProcedureInterrupts Generated by the USB Controller USB Interrupt Conditions USB Interrupt Conditions DMA Interrupts Test ModesUSB Core Interrupts Testk TESTSE0NAKTestj Testpacket Forcehost Power Management Reset ConsiderationsInterrupt Support Edma Event Support Transmit/Receive Cppi Channel 0 State Block Universal Serial Bus USB RegistersAcronym Register Description Offset Acronym Register Description Common USB Registers FIFOn Target Endpoint 1 Control Registers, Valid Only in Host Mode Control and Status Register for Endpoint Target Endpoint 4 Control Registers, Valid Only in Host Mode 51Dh Bit Field Value Description Control Register CtrlrControl Register Ctrlr Field Descriptions Rndis Register Rndisr Status Register StatrStatus Register Statr Field Descriptions Rndis Register Rndisr Field Descriptions Auto Request Register Autoreq Field Descriptions Auto Request Register Autoreq USB USB Interrupt Source Register IntsrcrUSB Interrupt Source Register Intsrcr Field Descriptions USB Interrupt Source Set Register Intsetr USB Interrupt Source Set Register Intsetr USB Interrupt Source Clear Register Intclrr USB Interrupt Source Clear Register Intclrr USB Interrupt Mask Register Intmskr Field Descriptions USB Interrupt Mask Register Intmskr USB Interrupt Mask Set Register Intmsksetr USB Interrupt Mask Set Register Intmsksetr USB Interrupt Mask Clear Register Intmskclrr USB Interrupt Mask Clear Register Intmskclrr USB Interrupt Source Masked Register Intmaskedr USB Interrupt Source Masked Register Intmaskedr USB Interrupt Vector Register Intvectr USB End of Interrupt Register EoirUSB End of Interrupt Register Eoir Field Descriptions USB Interrupt Vector Register Intvectr Field Descriptions Transmit Cppi Teardown Register Tcppitdr Transmit Cppi Control Register TcppicrTransmit Cppi Control Register Tcppicr Field Descriptions Transmit Cppi Teardown Register Tcppitdr Field Descriptions Cppi DMA End of Interrupt Register Cppieoir Cppi DMA End of Interrupt Register Cppieoir Transmit Cppi Raw Status Register Tcppirawsr Transmit Cppi Masked Status Register TcppimsksrMasked Comppending Comppending Comppendingintren Transmit Cppi Interrupt Enable Set Register TcppiiensetrTransmit Cppi Interrupt Enable Clear Register Tcppiienclrr Receive Cppi Control Register Rcppicr RcppienableReceive Cppi Masked Status Register Rcppimsksr Receive Cppi Control Register Rcppicr Field Descriptions Receive Cppi Raw Status Register Rcppirawsr Receive Cppi Interrupt Enable Set Register Rcppiensetr Receive Buffer Count 0 Register RBUFCNT0 Receive Cppi Interrupt Enable Clear Register RcppiienclrrReceive Buffer Count 0 Register RBUFCNT0 Field Descriptions Bufcnt Receive Buffer Count 2 Register RBUFCNT2 Receive Buffer Count 1 Register RBUFCNT1Receive Buffer Count 1 Register RBUFCNT1 Field Descriptions Receive Buffer Count 2 Register RBUFCNT2 Field Descriptions Transmit Cppi DMA State Word 0 TCPPIDMASTATEW0 Receive Buffer Count 3 Register RBUFCNT3Receive Buffer Count 3 Register RBUFCNT3 Field Descriptions Txqheadptr Transmit Cppi DMA State Word 2 TCPPIDMASTATEW2 Transmit Cppi DMA State Word 1 TCPPIDMASTATEW1Sopdescriptorptr Currdescriptorptr Truncatednoneop Transmit Cppi DMA State Word 4 TCPPIDMASTATEW4 Transmit Cppi DMA State Word 3 TCPPIDMASTATEW3 Transmit Cppi Completion Pointer Tcppicompptr Transmit Cppi DMA State Word 5 TCPPIDMASTATEW5 Sopbufferoffset Receive Cppi DMA State Word 0 RCPPIDMASTATEW0Receive Cppi DMA State Word 1 RCPPIDMASTATEW1 Rxqheadptr Receive Cppi DMA State Word 1 RCPPIDMASTATEW1 Receive Cppi DMA State Word 3 RCPPIDMASTATEW3 Receive Cppi DMA State Word 2 RCPPIDMASTATEW2 108 Pktlength Receive Cppi DMA State Word 4 RCPPIDMASTATEW4Receive Cppi DMA State Word 5 RCPPIDMASTATEW5 Receive Cppi Completion Pointer Rcppicompptr Receive Cppi DMA State Word 6 RCPPIDMASTATEW6Sopbufferbytecnt Currbufferbytecnt Power Management Register Power Field Descriptions Power Management Register PowerReadback / Compare Mode Function Address Register Faddr Field Descriptions Interrupt Register for Receive Endpoints 1 to 4 IntrrxEP4TX EP3TX EP2TX EP1TX EP0 EP4TX Interrupt Enable Register for Intrrx Intrrxe Interrupt Enable Register for Intrtx IntrtxeEP4RX EP3RX EP2RX EP1RX EP4RX Interrupt Enable Register for Intrrx Intrrxe Vbuserr Vbuserr Sessreq Discon Conn SOF Resetbabble Resume SuspendInterrupt Register for Common USB Interrupts Intrusb Interrupt Enable Register for Intrusb Intrusbe Interrupt Enable Register for Intrusb Intrusbe Frame Number Register Frame Field Descriptions Frame Number Register FrameFramenumber Epsel Forcehost Register to Enable the USB 2.0 Test Modes TestmodeForcefs Forcehs Maxpayload Setupend ServsetupendFlushfifo Servrxpktrdy Datatog Datatogwren Clrdatatog ISO Mode Dmaen Frcdatatog Dmamode Control Status Register for Host Transmit Endpoint Hosttxcsr 124 ISO Dmaen Disnyet Dmamode Dmaen Disnyet Dmamode Datatogwren DataerrnaktimeoutControl Status Register for Host Receive Endpoint Hostrxcsr 127 Receive Count Register Rxcount Count 0 Register COUNT0Count 0 Register COUNT0 Field Descriptions Receive Count Register Rxcount Field Descriptions Transmit Type Register Host mode only Hosttxtype Type Register Host mode only HOSTTYPE0Type Register Host mode only HOSTTYPE0 Field Descriptions Speed Transmit Interval Register Host mode only Hosttxinterval NAKLimit0 Register Host mode only HOSTNAKLIMIT0EP0NAKLIMIT Polintvlnaklimit Speed Prot Rendpn Receive Type Register Host mode only HostrxtypeReceive Interval Register Host mode only Hostrxinterval Mprxe Configuration Data Register ConfigdataConfiguration Data Register Configdata Field Descriptions 133 Data Transmit and Receive Fifo Register for Endpoint 0 FIFO0 Data Ffff Ffff Transmit and Receive Fifo Register for Endpoint 1 FIFO1Transmit and Receive Fifo Register for Endpoint 2 FIFO2 Transmit and Receive Fifo Register for Endpoint 4 FIFO4 Transmit and Receive Fifo Register for Endpoint 3 FIFO3 OTG Device Control Register Devctl Field Descriptions OTG Device Control Register DevctlBdevice Fsdev Lsdev Vbus Hostmode Hostreq Session Bdevice Receive Endpoint Fifo Size Rxfifosz Transmit Endpoint Fifo Size TxfifoszTransmit Endpoint Fifo Size Txfifosz Field Descriptions Receive Endpoint Fifo Size Rxfifosz Field Descriptions Receive Endpoint Fifo Address Rxfifoaddr Transmit Endpoint Fifo Address TxfifoaddrReceive Endpoint Fifo Address Rxfifoaddr Field Descriptions Addr Transmit Hub Port Txhubport Transmit Function Address TxfuncaddrTransmit Hub Address Txhubaddr Receive Hub Port Rxhubport Receive Function Address RxfuncaddrReceive Hub Address Rxhubaddr 142 Additions/Modifications/Deletions Table A-1. 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