From: Nabih Estefan Diaz <nabihestefan@google.com>
- Implementation of Transmit function for packets
- Implementation for reading and writing from and to descriptors in
memory for Tx
NOTE: This function implements the steps detailed in the datasheet for
transmitting messages from the GMAC.
Signed-off-by: Nabih Estefan Diaz <nabihestefan@google.com>
---
hw/net/npcm_gmac.c | 152 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 152 insertions(+)
diff --git a/hw/net/npcm_gmac.c b/hw/net/npcm_gmac.c
index a7c8b67223..688ac4be44 100644
--- a/hw/net/npcm_gmac.c
+++ b/hw/net/npcm_gmac.c
@@ -266,6 +266,7 @@ static int gmac_write_tx_desc(dma_addr_t addr, struct NPCMGMACTxDesc *desc)
}
return 0;
}
+
static int gmac_rx_transfer_frame_to_buffer(uint32_t rx_buf_len,
uint32_t *left_frame,
uint32_t rx_buf_addr,
@@ -487,6 +488,157 @@ static ssize_t gmac_receive(NetClientState *nc, const uint8_t *buf, size_t len)
gmac->regs[R_NPCM_DMA_HOST_RX_DESC] = desc_addr;
return len;
}
+
+static int gmac_tx_get_csum(uint32_t tdes1)
+{
+ uint32_t mask = TX_DESC_TDES1_CHKSM_INS_CTRL_MASK(tdes1);
+ int csum = 0;
+
+ if (likely(mask > 0)) {
+ csum |= CSUM_IP;
+ }
+ if (likely(mask > 1)) {
+ csum |= CSUM_TCP | CSUM_UDP;
+ }
+
+ return csum;
+}
+
+static void gmac_try_send_next_packet(NPCMGMACState *gmac)
+{
+ /*
+ * Comments about steps refer to steps for
+ * transmitting in page 384 of datasheet
+ */
+ uint16_t tx_buffer_size = 2048;
+ g_autofree uint8_t *tx_send_buffer = g_malloc(tx_buffer_size);
+ uint32_t desc_addr;
+ struct NPCMGMACTxDesc tx_desc;
+ uint32_t tx_buf_addr, tx_buf_len;
+ uint16_t length = 0;
+ uint8_t *buf = tx_send_buffer;
+ uint32_t prev_buf_size = 0;
+ int csum = 0;
+
+ /* steps 1&2 */
+ if (!gmac->regs[R_NPCM_DMA_HOST_TX_DESC]) {
+ gmac->regs[R_NPCM_DMA_HOST_TX_DESC] =
+ NPCM_DMA_HOST_TX_DESC_MASK(gmac->regs[R_NPCM_DMA_TX_BASE_ADDR]);
+ }
+ desc_addr = gmac->regs[R_NPCM_DMA_HOST_TX_DESC];
+
+ while (true) {
+ gmac_dma_set_state(gmac, NPCM_DMA_STATUS_TX_PROCESS_STATE_SHIFT,
+ NPCM_DMA_STATUS_TX_RUNNING_FETCHING_STATE);
+ trace_npcm_gmac_packet_transmit(DEVICE(gmac)->canonical_path, length);
+ if (gmac_read_tx_desc(desc_addr, &tx_desc)) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "TX Descriptor @ 0x%x can't be read\n",
+ desc_addr);
+ return;
+ }
+ /* step 3 */
+
+ trace_npcm_gmac_packet_desc_read(DEVICE(gmac)->canonical_path,
+ desc_addr);
+ trace_npcm_gmac_debug_desc_data(DEVICE(gmac)->canonical_path, &tx_desc,
+ tx_desc.tdes0, tx_desc.tdes1, tx_desc.tdes2, tx_desc.tdes3);
+
+ /* 1 = DMA Owned, 0 = Software Owned */
+ if (!(tx_desc.tdes0 & TX_DESC_TDES0_OWN)) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "TX Descriptor @ 0x%x is owned by software\n",
+ desc_addr);
+ gmac->regs[R_NPCM_DMA_STATUS] |= NPCM_DMA_STATUS_TU;
+ gmac_dma_set_state(gmac, NPCM_DMA_STATUS_TX_PROCESS_STATE_SHIFT,
+ NPCM_DMA_STATUS_TX_SUSPENDED_STATE);
+ gmac_update_irq(gmac);
+ return;
+ }
+
+ gmac_dma_set_state(gmac, NPCM_DMA_STATUS_TX_PROCESS_STATE_SHIFT,
+ NPCM_DMA_STATUS_TX_RUNNING_READ_STATE);
+ /* Give the descriptor back regardless of what happens. */
+ tx_desc.tdes0 &= ~TX_DESC_TDES0_OWN;
+
+ if (tx_desc.tdes1 & TX_DESC_TDES1_FIRST_SEG_MASK) {
+ csum = gmac_tx_get_csum(tx_desc.tdes1);
+ }
+
+ /* step 4 */
+ tx_buf_addr = tx_desc.tdes2;
+ gmac->regs[R_NPCM_DMA_CUR_TX_BUF_ADDR] = tx_buf_addr;
+ tx_buf_len = TX_DESC_TDES1_BFFR1_SZ_MASK(tx_desc.tdes1);
+ buf = &tx_send_buffer[prev_buf_size];
+
+ if ((prev_buf_size + tx_buf_len) > sizeof(buf)) {
+ tx_buffer_size = prev_buf_size + tx_buf_len;
+ tx_send_buffer = g_realloc(tx_send_buffer, tx_buffer_size);
+ buf = &tx_send_buffer[prev_buf_size];
+ }
+
+ /* step 5 */
+ if (dma_memory_read(&address_space_memory, tx_buf_addr, buf,
+ tx_buf_len, MEMTXATTRS_UNSPECIFIED)) {
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: Failed to read packet @ 0x%x\n",
+ __func__, tx_buf_addr);
+ return;
+ }
+ length += tx_buf_len;
+ prev_buf_size += tx_buf_len;
+
+ /* If not chained we'll have a second buffer. */
+ if (!(tx_desc.tdes1 & TX_DESC_TDES1_SEC_ADDR_CHND_MASK)) {
+ tx_buf_addr = tx_desc.tdes3;
+ gmac->regs[R_NPCM_DMA_CUR_TX_BUF_ADDR] = tx_buf_addr;
+ tx_buf_len = TX_DESC_TDES1_BFFR2_SZ_MASK(tx_desc.tdes1);
+ buf = &tx_send_buffer[prev_buf_size];
+
+ if ((prev_buf_size + tx_buf_len) > sizeof(buf)) {
+ tx_buffer_size = prev_buf_size + tx_buf_len;
+ tx_send_buffer = g_realloc(tx_send_buffer, tx_buffer_size);
+ buf = &tx_send_buffer[prev_buf_size];
+ }
+
+ if (dma_memory_read(&address_space_memory, tx_buf_addr, buf,
+ tx_buf_len, MEMTXATTRS_UNSPECIFIED)) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: Failed to read packet @ 0x%x\n",
+ __func__, tx_buf_addr);
+ return;
+ }
+ length += tx_buf_len;
+ prev_buf_size += tx_buf_len;
+ }
+ if (tx_desc.tdes1 & TX_DESC_TDES1_LAST_SEG_MASK) {
+ net_checksum_calculate(tx_send_buffer, length, csum);
+ qemu_send_packet(qemu_get_queue(gmac->nic), tx_send_buffer, length);
+ trace_npcm_gmac_packet_sent(DEVICE(gmac)->canonical_path, length);
+ buf = tx_send_buffer;
+ length = 0;
+ }
+
+ /* step 6 */
+ gmac_dma_set_state(gmac, NPCM_DMA_STATUS_TX_PROCESS_STATE_SHIFT,
+ NPCM_DMA_STATUS_TX_RUNNING_CLOSING_STATE);
+ gmac_write_tx_desc(desc_addr, &tx_desc);
+ if (tx_desc.tdes1 & TX_DESC_TDES1_TX_END_RING_MASK) {
+ desc_addr = gmac->regs[R_NPCM_DMA_TX_BASE_ADDR];
+ } else if (tx_desc.tdes1 & TX_DESC_TDES1_SEC_ADDR_CHND_MASK) {
+ desc_addr = tx_desc.tdes3;
+ } else {
+ desc_addr += sizeof(tx_desc);
+ }
+ gmac->regs[R_NPCM_DMA_HOST_TX_DESC] = desc_addr;
+
+ /* step 7 */
+ if (tx_desc.tdes1 & TX_DESC_TDES1_INTERR_COMP_MASK) {
+ gmac->regs[R_NPCM_DMA_STATUS] |= NPCM_DMA_STATUS_TI;
+ gmac_update_irq(gmac);
+ }
+ }
+}
+
static void gmac_cleanup(NetClientState *nc)
{
/* Nothing to do yet. */
--
2.42.0.655.g421f12c284-goog