/* * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD * * SPDX-License-Identifier: Apache-2.0 */ #include #include "sdkconfig.h" #include "esp_attr.h" #include "hal/emac_hal.h" #include "hal/emac_ll.h" #include "hal/gpio_ll.h" #define ETH_CRC_LENGTH (4) static esp_err_t emac_hal_flush_trans_fifo(emac_hal_context_t *hal) { emac_ll_flush_trans_fifo_enable(hal->dma_regs, true); /* no other writes to the Operation Mode register until the flush tx fifo bit is cleared */ for (uint32_t i = 0; i < 1000; i++) { if (emac_ll_get_flush_trans_fifo(hal->dma_regs) == 0) { return ESP_OK; } } return ESP_ERR_TIMEOUT; } void emac_hal_iomux_init_mii(void) { /* TX_CLK to GPIO0 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO0_U, FUNC_GPIO0_EMAC_TX_CLK); PIN_INPUT_ENABLE(GPIO_PIN_MUX_REG[0]); /* TX_EN to GPIO21 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO21_U, FUNC_GPIO21_EMAC_TX_EN); PIN_INPUT_DISABLE(GPIO_PIN_MUX_REG[21]); /* TXD0 to GPIO19 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO19_U, FUNC_GPIO19_EMAC_TXD0); PIN_INPUT_DISABLE(GPIO_PIN_MUX_REG[19]); /* TXD1 to GPIO22 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO22_U, FUNC_GPIO22_EMAC_TXD1); PIN_INPUT_DISABLE(GPIO_PIN_MUX_REG[22]); /* TXD2 to MTMS */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_MTMS_U, FUNC_MTMS_EMAC_TXD2); PIN_INPUT_DISABLE(GPIO_PIN_MUX_REG[14]); /* TXD3 to MTDI */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_MTDI_U, FUNC_MTDI_EMAC_TXD3); PIN_INPUT_DISABLE(GPIO_PIN_MUX_REG[12]); /* RX_CLK to GPIO5 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO5_U, FUNC_GPIO5_EMAC_RX_CLK); PIN_INPUT_ENABLE(GPIO_PIN_MUX_REG[5]); /* RX_DV to GPIO27 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO27_U, FUNC_GPIO27_EMAC_RX_DV); PIN_INPUT_ENABLE(GPIO_PIN_MUX_REG[27]); /* RXD0 to GPIO25 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO25_U, FUNC_GPIO25_EMAC_RXD0); PIN_INPUT_ENABLE(GPIO_PIN_MUX_REG[25]); /* RXD1 to GPIO26 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO26_U, FUNC_GPIO26_EMAC_RXD1); PIN_INPUT_ENABLE(GPIO_PIN_MUX_REG[26]); /* RXD2 to U0TXD */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_U0TXD_U, FUNC_U0TXD_EMAC_RXD2); PIN_INPUT_ENABLE(GPIO_PIN_MUX_REG[1]); /* RXD3 to MTDO */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_MTDO_U, FUNC_MTDO_EMAC_RXD3); PIN_INPUT_ENABLE(GPIO_PIN_MUX_REG[15]); } void emac_hal_iomux_rmii_clk_input(void) { /* REF_CLK(RMII mode) to GPIO0 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO0_U, FUNC_GPIO0_EMAC_TX_CLK); PIN_INPUT_ENABLE(GPIO_PIN_MUX_REG[0]); } void emac_hal_iomux_rmii_clk_ouput(int num) { switch (num) { case 0: /* APLL clock output to GPIO0 (must be configured to 50MHz!) */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO0_U, FUNC_GPIO0_CLK_OUT1); PIN_INPUT_DISABLE(GPIO_PIN_MUX_REG[0]); break; case 16: /* RMII CLK (50MHz) output to GPIO16 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO16_U, FUNC_GPIO16_EMAC_CLK_OUT); PIN_INPUT_DISABLE(GPIO_PIN_MUX_REG[16]); break; case 17: /* RMII CLK (50MHz) output to GPIO17 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO17_U, FUNC_GPIO17_EMAC_CLK_OUT_180); PIN_INPUT_DISABLE(GPIO_PIN_MUX_REG[17]); break; default: break; } } void emac_hal_iomux_init_rmii(void) { /* TX_EN to GPIO21 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO21_U, FUNC_GPIO21_EMAC_TX_EN); PIN_INPUT_DISABLE(GPIO_PIN_MUX_REG[21]); /* TXD0 to GPIO19 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO19_U, FUNC_GPIO19_EMAC_TXD0); PIN_INPUT_DISABLE(GPIO_PIN_MUX_REG[19]); /* TXD1 to GPIO22 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO22_U, FUNC_GPIO22_EMAC_TXD1); PIN_INPUT_DISABLE(GPIO_PIN_MUX_REG[22]); /* CRS_DV to GPIO27 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO27_U, FUNC_GPIO27_EMAC_RX_DV); PIN_INPUT_ENABLE(GPIO_PIN_MUX_REG[27]); /* RXD0 to GPIO25 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO25_U, FUNC_GPIO25_EMAC_RXD0); PIN_INPUT_ENABLE(GPIO_PIN_MUX_REG[25]); /* RXD1 to GPIO26 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO26_U, FUNC_GPIO26_EMAC_RXD1); PIN_INPUT_ENABLE(GPIO_PIN_MUX_REG[26]); } void emac_hal_iomux_init_tx_er(void) { /* TX_ER to GPIO4 */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_GPIO4_U, FUNC_GPIO4_EMAC_TX_ER); PIN_INPUT_DISABLE(GPIO_PIN_MUX_REG[4]); } void emac_hal_iomux_init_rx_er(void) { /* RX_ER to MTCK */ gpio_ll_iomux_func_sel(PERIPHS_IO_MUX_MTCK_U, FUNC_MTCK_EMAC_RX_ER); PIN_INPUT_ENABLE(GPIO_PIN_MUX_REG[13]); } void emac_hal_init(emac_hal_context_t *hal, void *descriptors, uint8_t **rx_buf, uint8_t **tx_buf) { hal->dma_regs = &EMAC_DMA; hal->mac_regs = &EMAC_MAC; hal->ext_regs = &EMAC_EXT; hal->descriptors = descriptors; hal->rx_buf = rx_buf; hal->tx_buf = tx_buf; } void emac_hal_set_csr_clock_range(emac_hal_context_t *hal, int freq) { /* Tell MAC system clock Frequency in MHz, which will determine the frequency range of MDC(1MHz~2.5MHz) */ if (freq >= 20000000 && freq < 35000000) { emac_ll_set_csr_clock_division(hal->mac_regs, 2); // CSR clock/16 } else if (freq >= 35000000 && freq < 60000000) { emac_ll_set_csr_clock_division(hal->mac_regs, 3); // CSR clock/26 } else if (freq >= 60000000 && freq < 100000000) { emac_ll_set_csr_clock_division(hal->mac_regs, 0); // CSR clock/42 } else if (freq >= 100000000 && freq < 150000000) { emac_ll_set_csr_clock_division(hal->mac_regs, 1); // CSR clock/62 } else if (freq >= 150000000 && freq < 250000000) { emac_ll_set_csr_clock_division(hal->mac_regs, 4); // CSR clock/102 } else { emac_ll_set_csr_clock_division(hal->mac_regs, 5); // CSR clock/124 } } void emac_hal_reset_desc_chain(emac_hal_context_t *hal) { /* reset DMA descriptors */ hal->rx_desc = (eth_dma_rx_descriptor_t *)(hal->descriptors); hal->tx_desc = (eth_dma_tx_descriptor_t *)(hal->descriptors + sizeof(eth_dma_rx_descriptor_t) * CONFIG_ETH_DMA_RX_BUFFER_NUM); /* init rx chain */ for (int i = 0; i < CONFIG_ETH_DMA_RX_BUFFER_NUM; i++) { /* Set Own bit of the Rx descriptor Status: DMA */ hal->rx_desc[i].RDES0.Own = EMAC_LL_DMADESC_OWNER_DMA; /* Set Buffer1 size and Second Address Chained bit */ hal->rx_desc[i].RDES1.SecondAddressChained = 1; hal->rx_desc[i].RDES1.ReceiveBuffer1Size = CONFIG_ETH_DMA_BUFFER_SIZE; /* Enable Ethernet DMA Rx Descriptor interrupt */ hal->rx_desc[i].RDES1.DisableInterruptOnComplete = 0; /* point to the buffer */ hal->rx_desc[i].Buffer1Addr = (uint32_t)(hal->rx_buf[i]); /* point to next descriptor */ hal->rx_desc[i].Buffer2NextDescAddr = (uint32_t)(hal->rx_desc + i + 1); } /* For last descriptor, set next descriptor address register equal to the first descriptor base address */ hal->rx_desc[CONFIG_ETH_DMA_RX_BUFFER_NUM - 1].Buffer2NextDescAddr = (uint32_t)(hal->rx_desc); /* init tx chain */ for (int i = 0; i < CONFIG_ETH_DMA_TX_BUFFER_NUM; i++) { /* Set Own bit of the Tx descriptor Status: CPU */ hal->tx_desc[i].TDES0.Own = EMAC_LL_DMADESC_OWNER_CPU; hal->tx_desc[i].TDES0.SecondAddressChained = 1; hal->tx_desc[i].TDES1.TransmitBuffer1Size = CONFIG_ETH_DMA_BUFFER_SIZE; /* Enable Ethernet DMA Tx Descriptor interrupt */ hal->tx_desc[1].TDES0.InterruptOnComplete = 1; /* Enable Transmit Timestamp */ hal->tx_desc[i].TDES0.TransmitTimestampEnable = 1; /* point to the buffer */ hal->tx_desc[i].Buffer1Addr = (uint32_t)(hal->tx_buf[i]); /* point to next descriptor */ hal->tx_desc[i].Buffer2NextDescAddr = (uint32_t)(hal->tx_desc + i + 1); } /* For last descriptor, set next descriptor address register equal to the first descriptor base address */ hal->tx_desc[CONFIG_ETH_DMA_TX_BUFFER_NUM - 1].Buffer2NextDescAddr = (uint32_t)(hal->tx_desc); /* set base address of the first descriptor */ emac_ll_set_rx_desc_addr(hal->dma_regs, (uint32_t)hal->rx_desc); emac_ll_set_tx_desc_addr(hal->dma_regs, (uint32_t)hal->tx_desc); } void emac_hal_init_mac_default(emac_hal_context_t *hal) { /* MACCR Configuration */ /* Enable the watchdog on the receiver, frame longer than 2048 Bytes is not allowed */ emac_ll_watchdog_enable(hal->mac_regs, true); /* Enable the jabber timer on the transmitter, frame longer than 2048 Bytes is not allowed */ emac_ll_jabber_enable(hal->mac_regs, true); /* minimum IFG between frames during transmission is 96 bit times */ emac_ll_set_inter_frame_gap(hal->mac_regs, EMAC_LL_INTERFRAME_GAP_96BIT); /* Enable Carrier Sense During Transmission */ emac_ll_carrier_sense_enable(hal->mac_regs, true); /* Select speed: port: 10/100 Mbps, here set default 100M, afterwards, will reset by auto-negotiation */ emac_ll_set_port_speed(hal->mac_regs, ETH_SPEED_100M);; /* Allow the reception of frames when the TX_EN signal is asserted in Half-Duplex mode */ emac_ll_recv_own_enable(hal->mac_regs, true); /* Disable internal loopback mode */ emac_ll_loopback_enable(hal->mac_regs, false); /* Select duplex mode: here set default full duplex, afterwards, will reset by auto-negotiation */ emac_ll_set_duplex(hal->mac_regs, ETH_DUPLEX_FULL); /* Select the checksum mode for received frame payload's TCP/UDP/ICMP headers */ emac_ll_checksum_offload_mode(hal->mac_regs, ETH_CHECKSUM_HW); /* Enable MAC retry transmission when a colision occurs in half duplex mode */ emac_ll_retry_enable(hal->mac_regs, true); /* MAC passes all incoming frames to host, without modifying them */ emac_ll_auto_pad_crc_strip_enable(hal->mac_regs, false); /* Set Back-Off limit time before retry a transmittion after a collision */ emac_ll_set_back_off_limit(hal->mac_regs, EMAC_LL_BACKOFF_LIMIT_10); /* Disable deferral check, MAC defers until the CRS signal goes inactive */ emac_ll_deferral_check_enable(hal->mac_regs, false); /* Set preamble length 7 Bytes */ emac_ll_set_preamble_length(hal->mac_regs, EMAC_LL_PREAMBLE_LENGTH_7); /* MACFFR Configuration */ /* Receiver module passes only those frames to the Application that pass the SA or DA address filter */ emac_ll_receive_all_enable(hal->mac_regs, false); /* Disable source address filter */ emac_ll_set_src_addr_filter(hal->mac_regs, EMAC_LL_SOURCE_ADDR_FILTER_DISABLE); emac_ll_sa_inverse_filter_enable(hal->mac_regs, false); /* MAC blocks all control frames */ emac_ll_set_pass_ctrl_frame_mode(hal->mac_regs, EMAC_LL_CONTROL_FRAME_BLOCKALL); /* AFM module passes all received broadcast frames and multicast frames */ emac_ll_broadcast_frame_enable(hal->mac_regs, true); emac_ll_pass_all_multicast_enable(hal->mac_regs, true); /* Address Check block operates in normal filtering mode for the DA address */ emac_ll_da_inverse_filter_enable(hal->mac_regs, false); /* Disable Promiscuous Mode */ emac_ll_promiscuous_mode_enable(hal->mac_regs, false); } void emac_hal_enable_flow_ctrl(emac_hal_context_t *hal, bool enable) { /* MACFCR Configuration */ if (enable) { /* Pause time */ emac_ll_set_pause_time(hal->mac_regs, EMAC_LL_PAUSE_TIME); /* Enable generation of Zero-Quanta Pause Control frames */ emac_ll_zero_quanta_pause_enable(hal->mac_regs, true); /* Threshold of the PAUSE to be checked for automatic retransmission of PAUSE Frame */ emac_ll_set_pause_low_threshold(hal->mac_regs, EMAC_LL_PAUSE_LOW_THRESHOLD_MINUS_28); /* Don't allow MAC detect Pause frames with MAC address0 unicast address and unique multicast address */ emac_ll_unicast_pause_frame_detect_enable(hal->mac_regs, false); /* Enable MAC to decode the received Pause frame and disable its transmitter for a specific time */ emac_ll_receive_flow_ctrl_enable(hal->mac_regs, true); /* Enable MAC to transmit Pause frames in full duplex mode or the MAC back-pressure operation in half duplex mode */ emac_ll_transmit_flow_ctrl_enable(hal->mac_regs, true); } else { emac_ll_clear(hal->mac_regs); } } void emac_hal_init_dma_default(emac_hal_context_t *hal) { /* DMAOMR Configuration */ /* Enable Dropping of TCP/IP Checksum Error Frames */ emac_ll_drop_tcp_err_frame_enable(hal->dma_regs, true); /* Enable Receive Store Forward */ emac_ll_recv_store_forward_enable(hal->dma_regs, true); /* Enable Flushing of Received Frames because of the unavailability of receive descriptors or buffers */ emac_ll_flush_recv_frame_enable(hal->dma_regs, true); /* Disable Transmit Store Forward */ emac_ll_trans_store_forward_enable(hal->dma_regs, false); /* Flush Transmit FIFO */ emac_hal_flush_trans_fifo(hal); /* Transmit Threshold Control */ emac_ll_set_transmit_threshold(hal->dma_regs, EMAC_LL_TRANSMIT_THRESHOLD_CONTROL_64); /* Disable Forward Error Frame */ emac_ll_forward_err_frame_enable(hal->dma_regs, false); /* Disable forward undersized good frame */ emac_ll_forward_undersized_good_frame_enable(hal->dma_regs, false); /* Receive Threshold Control */ emac_ll_set_recv_threshold(hal->dma_regs, EMAC_LL_RECEIVE_THRESHOLD_CONTROL_64); /* Allow the DMA to process a second frame of Transmit data even before obtaining the status for the first frame */ emac_ll_opt_second_frame_enable(hal->dma_regs, true);; /* DMABMR Configuration */ /* Enable Mixed Burst */ emac_ll_mixed_burst_enable(hal->dma_regs, true); /* Enable Address Aligned Beates */ emac_ll_addr_align_enable(hal->dma_regs, true); /* Use Separate PBL */ emac_ll_use_separate_pbl_enable(hal->dma_regs, true); /* Set Rx/Tx DMA Burst Length */ emac_ll_set_rx_dma_pbl(hal->dma_regs, EMAC_LL_DMA_BURST_LENGTH_32BEAT); emac_ll_set_prog_burst_len(hal->dma_regs, EMAC_LL_DMA_BURST_LENGTH_32BEAT); /* Enable Enhanced Descriptor,8 Words(32 Bytes) */ emac_ll_enhance_desc_enable(hal->dma_regs, true); /* Specifies the number of word to skip between two unchained descriptors (Ring mode) */ emac_ll_set_desc_skip_len(hal->dma_regs, 0); /* DMA Arbitration Scheme */ emac_ll_fixed_arbitration_enable(hal->dma_regs, false); /* Set priority ratio in the weighted round-robin arbitration between Rx DMA and Tx DMA */ emac_ll_set_priority_ratio(hal->dma_regs, EMAC_LL_DMA_ARBITRATION_ROUNDROBIN_RXTX_1_1); } void emac_hal_set_phy_cmd(emac_hal_context_t *hal, uint32_t phy_addr, uint32_t phy_reg, bool write) { /* Write the result value into the MII Address register */ emac_ll_set_phy_addr(hal->mac_regs, phy_addr); /* Set the PHY register address */ emac_ll_set_phy_reg(hal->mac_regs, phy_reg); /* Set as write mode */ emac_ll_write_enable(hal->mac_regs, write); /* Set MII busy bit */ emac_ll_set_busy(hal->mac_regs, true); } void emac_hal_set_address(emac_hal_context_t *hal, uint8_t *mac_addr) { /* Make sure mac address is unicast type */ if (!(mac_addr[0] & 0x01)) { emac_ll_set_addr(hal->mac_regs, mac_addr); } } void emac_hal_start(emac_hal_context_t *hal) { /* Enable Ethernet MAC and DMA Interrupt */ emac_ll_enable_corresponding_intr(hal->dma_regs, EMAC_LL_CONFIG_ENABLE_INTR_MASK); /* Clear all pending interrupts */ emac_ll_clear_all_pending_intr(hal->dma_regs); /* Enable transmit state machine of the MAC for transmission on the MII */ emac_ll_transmit_enable(hal->mac_regs, true); /* Start DMA transmission */ /* Note that the EMAC Databook states the DMA could be started prior enabling the MAC transmitter. However, it turned out that such order may cause the MAC transmitter hangs */ emac_ll_start_stop_dma_transmit(hal->dma_regs, true); /* Start DMA reception */ emac_ll_start_stop_dma_receive(hal->dma_regs, true); /* Enable receive state machine of the MAC for reception from the MII */ emac_ll_receive_enable(hal->mac_regs, true); } esp_err_t emac_hal_stop(emac_hal_context_t *hal) { /* Stop DMA transmission */ emac_ll_start_stop_dma_transmit(hal->dma_regs, false); if (emac_ll_transmit_frame_ctrl_status(hal->mac_regs) != 0x0) { /* Previous transmit in progress */ return ESP_ERR_INVALID_STATE; } /* Disable transmit state machine of the MAC for transmission on the MII */ emac_ll_receive_enable(hal->mac_regs, false); /* Disable receive state machine of the MAC for reception from the MII */ emac_ll_transmit_enable(hal->mac_regs, false); if (emac_ll_receive_read_ctrl_state(hal->mac_regs) != 0x0) { /* Previous receive copy in progress */ return ESP_ERR_INVALID_STATE; } /* Stop DMA reception */ emac_ll_start_stop_dma_receive(hal->dma_regs, false); /* Flush Transmit FIFO */ emac_hal_flush_trans_fifo(hal); /* Disable Ethernet MAC and DMA Interrupt */ emac_ll_disable_all_intr(hal->dma_regs); return ESP_OK; } uint32_t emac_hal_get_tx_desc_owner(emac_hal_context_t *hal) { return hal->tx_desc->TDES0.Own; } uint32_t emac_hal_transmit_frame(emac_hal_context_t *hal, uint8_t *buf, uint32_t length) { /* Get the number of Tx buffers to use for the frame */ uint32_t bufcount = 0; uint32_t lastlen = length; uint32_t sentout = 0; while (lastlen > CONFIG_ETH_DMA_BUFFER_SIZE) { lastlen -= CONFIG_ETH_DMA_BUFFER_SIZE; bufcount++; } if (lastlen) { bufcount++; } if (bufcount > CONFIG_ETH_DMA_TX_BUFFER_NUM) { goto err; } eth_dma_tx_descriptor_t *desc_iter = hal->tx_desc; /* A frame is transmitted in multiple descriptor */ for (size_t i = 0; i < bufcount; i++) { /* Check if the descriptor is owned by the Ethernet DMA (when 1) or CPU (when 0) */ if (desc_iter->TDES0.Own != EMAC_LL_DMADESC_OWNER_CPU) { goto err; } /* Clear FIRST and LAST segment bits */ desc_iter->TDES0.FirstSegment = 0; desc_iter->TDES0.LastSegment = 0; desc_iter->TDES0.InterruptOnComplete = 0; if (i == 0) { /* Setting the first segment bit */ desc_iter->TDES0.FirstSegment = 1; } if (i == (bufcount - 1)) { /* Setting the last segment bit */ desc_iter->TDES0.LastSegment = 1; /* Enable transmit interrupt */ desc_iter->TDES0.InterruptOnComplete = 1; /* Program size */ desc_iter->TDES1.TransmitBuffer1Size = lastlen; /* copy data from uplayer stack buffer */ memcpy((void *)(desc_iter->Buffer1Addr), buf + i * CONFIG_ETH_DMA_BUFFER_SIZE, lastlen); sentout += lastlen; } else { /* Program size */ desc_iter->TDES1.TransmitBuffer1Size = CONFIG_ETH_DMA_BUFFER_SIZE; /* copy data from uplayer stack buffer */ memcpy((void *)(desc_iter->Buffer1Addr), buf + i * CONFIG_ETH_DMA_BUFFER_SIZE, CONFIG_ETH_DMA_BUFFER_SIZE); sentout += CONFIG_ETH_DMA_BUFFER_SIZE; } /* Point to next descriptor */ desc_iter = (eth_dma_tx_descriptor_t *)(desc_iter->Buffer2NextDescAddr); } /* Set Own bit of the Tx descriptor Status: gives the buffer back to ETHERNET DMA */ for (size_t i = 0; i < bufcount; i++) { hal->tx_desc->TDES0.Own = EMAC_LL_DMADESC_OWNER_DMA; hal->tx_desc = (eth_dma_tx_descriptor_t *)(hal->tx_desc->Buffer2NextDescAddr); } emac_ll_transmit_poll_demand(hal->dma_regs, 0); return sentout; err: return 0; } uint32_t emac_hal_receive_frame(emac_hal_context_t *hal, uint8_t *buf, uint32_t size, uint32_t *frames_remain, uint32_t *free_desc) { eth_dma_rx_descriptor_t *desc_iter = NULL; eth_dma_rx_descriptor_t *first_desc = NULL; uint32_t used_descs = 0; uint32_t seg_count = 0; uint32_t ret_len = 0; uint32_t copy_len = 0; uint32_t write_len = 0; uint32_t frame_count = 0; first_desc = hal->rx_desc; desc_iter = hal->rx_desc; /* Traverse descriptors owned by CPU */ while ((desc_iter->RDES0.Own != EMAC_LL_DMADESC_OWNER_DMA) && (used_descs < CONFIG_ETH_DMA_RX_BUFFER_NUM) && !frame_count) { used_descs++; seg_count++; /* Last segment in frame */ if (desc_iter->RDES0.LastDescriptor) { /* Get the Frame Length of the received packet: substruct 4 bytes of the CRC */ ret_len = desc_iter->RDES0.FrameLength - ETH_CRC_LENGTH; /* packets larger than expected will be truncated */ copy_len = ret_len > size ? size : ret_len; /* update unhandled frame count */ frame_count++; } /* First segment in frame */ if (desc_iter->RDES0.FirstDescriptor) { first_desc = desc_iter; } /* point to next descriptor */ desc_iter = (eth_dma_rx_descriptor_t *)(desc_iter->Buffer2NextDescAddr); } /* there's at least one frame to process */ if (frame_count) { /* check how many frames left to handle */ while ((desc_iter->RDES0.Own != EMAC_LL_DMADESC_OWNER_DMA) && (used_descs < CONFIG_ETH_DMA_RX_BUFFER_NUM)) { used_descs++; if (desc_iter->RDES0.LastDescriptor) { frame_count++; } /* point to next descriptor */ desc_iter = (eth_dma_rx_descriptor_t *)(desc_iter->Buffer2NextDescAddr); } desc_iter = first_desc; for (size_t i = 0; i < seg_count - 1; i++) { used_descs--; write_len = copy_len < CONFIG_ETH_DMA_BUFFER_SIZE ? copy_len : CONFIG_ETH_DMA_BUFFER_SIZE; /* copy data to buffer */ memcpy(buf, (void *)(desc_iter->Buffer1Addr), write_len); buf += write_len; copy_len -= write_len; /* Set Own bit in Rx descriptors: gives the buffers back to DMA */ desc_iter->RDES0.Own = EMAC_LL_DMADESC_OWNER_DMA; desc_iter = (eth_dma_rx_descriptor_t *)(desc_iter->Buffer2NextDescAddr); } memcpy(buf, (void *)(desc_iter->Buffer1Addr), copy_len); desc_iter->RDES0.Own = EMAC_LL_DMADESC_OWNER_DMA; /* update rxdesc */ hal->rx_desc = (eth_dma_rx_descriptor_t *)(desc_iter->Buffer2NextDescAddr); /* poll rx demand */ emac_ll_receive_poll_demand(hal->dma_regs, 0); frame_count--; used_descs--; } *frames_remain = frame_count; *free_desc = CONFIG_ETH_DMA_RX_BUFFER_NUM - used_descs; return ret_len; }