1 // SPDX-License-Identifier: GPL-2.0-only
3  * Qualcomm BAM-DMUX WWAN network driver
10 #include <linux/dma-mapping.h>
27 #define BAM_DMUX_MAX_DATA_SIZE		(BAM_DMUX_BUFFER_SIZE - BAM_DMUX_HDR_SIZE)
73 	struct qcom_smem_state *pc, *pc_ack;  member
98 	reinit_completion(&dmux->pc_ack_completion);  in bam_dmux_pc_vote()
99 	qcom_smem_state_update_bits(dmux->pc, dmux->pc_mask,  in bam_dmux_pc_vote()
100 				    enable ? dmux->pc_mask : 0);  in bam_dmux_pc_vote()
105 	qcom_smem_state_update_bits(dmux->pc_ack, dmux->pc_ack_mask,  in bam_dmux_pc_ack()
106 				    dmux->pc_ack_state ? 0 : dmux->pc_ack_mask);  in bam_dmux_pc_ack()
107 	dmux->pc_ack_state = !dmux->pc_ack_state;  in bam_dmux_pc_ack()
113 	struct device *dev = skb_dma->dmux->dev;  in bam_dmux_skb_dma_map()
115 	skb_dma->addr = dma_map_single(dev, skb_dma->skb->data, skb_dma->skb->len, dir);  in bam_dmux_skb_dma_map()
116 	if (dma_mapping_error(dev, skb_dma->addr)) {  in bam_dmux_skb_dma_map()
118 		skb_dma->addr = 0;  in bam_dmux_skb_dma_map()
128 	dma_unmap_single(skb_dma->dmux->dev, skb_dma->addr, skb_dma->skb->len, dir);  in bam_dmux_skb_dma_unmap()
129 	skb_dma->addr = 0;  in bam_dmux_skb_dma_unmap()
136 	dev_dbg(dmux->dev, "wake queues\n");  in bam_dmux_tx_wake_queues()
139 		struct net_device *netdev = dmux->netdevs[i];  in bam_dmux_tx_wake_queues()
150 	dev_dbg(dmux->dev, "stop queues\n");  in bam_dmux_tx_stop_queues()
153 		struct net_device *netdev = dmux->netdevs[i];  in bam_dmux_tx_stop_queues()
162 	struct bam_dmux *dmux = skb_dma->dmux;  in bam_dmux_tx_done()
165 	pm_runtime_mark_last_busy(dmux->dev);  in bam_dmux_tx_done()
166 	pm_runtime_put_autosuspend(dmux->dev);  in bam_dmux_tx_done()
168 	if (skb_dma->addr)  in bam_dmux_tx_done()
171 	spin_lock_irqsave(&dmux->tx_lock, flags);  in bam_dmux_tx_done()
172 	skb_dma->skb = NULL;  in bam_dmux_tx_done()
173 	if (skb_dma == &dmux->tx_skbs[dmux->tx_next_skb % BAM_DMUX_NUM_SKB])  in bam_dmux_tx_done()
175 	spin_unlock_irqrestore(&dmux->tx_lock, flags);  in bam_dmux_tx_done()
181 	struct sk_buff *skb = skb_dma->skb;  in bam_dmux_tx_callback()
189 	struct bam_dmux *dmux = skb_dma->dmux;  in bam_dmux_skb_dma_submit_tx()
192 	desc = dmaengine_prep_slave_single(dmux->tx, skb_dma->addr,  in bam_dmux_skb_dma_submit_tx()
193 					   skb_dma->skb->len, DMA_MEM_TO_DEV,  in bam_dmux_skb_dma_submit_tx()
196 		dev_err(dmux->dev, "Failed to prepare TX DMA buffer\n");  in bam_dmux_skb_dma_submit_tx()
200 	desc->callback = bam_dmux_tx_callback;  in bam_dmux_skb_dma_submit_tx()
201 	desc->callback_param = skb_dma;  in bam_dmux_skb_dma_submit_tx()
202 	desc->cookie = dmaengine_submit(desc);  in bam_dmux_skb_dma_submit_tx()
212 	spin_lock_irqsave(&dmux->tx_lock, flags);  in bam_dmux_tx_queue()
214 	skb_dma = &dmux->tx_skbs[dmux->tx_next_skb % BAM_DMUX_NUM_SKB];  in bam_dmux_tx_queue()
215 	if (skb_dma->skb) {  in bam_dmux_tx_queue()
217 		spin_unlock_irqrestore(&dmux->tx_lock, flags);  in bam_dmux_tx_queue()
220 	skb_dma->skb = skb;  in bam_dmux_tx_queue()
222 	dmux->tx_next_skb++;  in bam_dmux_tx_queue()
223 	if (dmux->tx_skbs[dmux->tx_next_skb % BAM_DMUX_NUM_SKB].skb)  in bam_dmux_tx_queue()
226 	spin_unlock_irqrestore(&dmux->tx_lock, flags);  in bam_dmux_tx_queue()
232 	struct bam_dmux *dmux = bndev->dmux;  in bam_dmux_send_cmd()
240 		return -ENOMEM;  in bam_dmux_send_cmd()
243 	hdr->magic = BAM_DMUX_HDR_MAGIC;  in bam_dmux_send_cmd()
244 	hdr->cmd = cmd;  in bam_dmux_send_cmd()
245 	hdr->ch = bndev->ch;  in bam_dmux_send_cmd()
249 		ret = -EAGAIN;  in bam_dmux_send_cmd()
253 	ret = pm_runtime_get_sync(dmux->dev);  in bam_dmux_send_cmd()
258 		ret = -ENOMEM;  in bam_dmux_send_cmd()
263 		ret = -EIO;  in bam_dmux_send_cmd()
267 	dma_async_issue_pending(dmux->tx);  in bam_dmux_send_cmd()
303 	return needed - avail;  in needed_room()
310 	unsigned int pad = sizeof(u32) - skb->len % sizeof(u32);  in bam_dmux_tx_prepare_skb()
322 	hdr->magic = BAM_DMUX_HDR_MAGIC;  in bam_dmux_tx_prepare_skb()
323 	hdr->signal = 0;  in bam_dmux_tx_prepare_skb()
324 	hdr->cmd = BAM_DMUX_CMD_DATA;  in bam_dmux_tx_prepare_skb()
325 	hdr->pad = pad;  in bam_dmux_tx_prepare_skb()
326 	hdr->ch = bndev->ch;  in bam_dmux_tx_prepare_skb()
327 	hdr->len = skb->len - sizeof(*hdr);  in bam_dmux_tx_prepare_skb()
338 	struct bam_dmux *dmux = bndev->dmux;  in bam_dmux_netdev_start_xmit()
346 	active = pm_runtime_get(dmux->dev);  in bam_dmux_netdev_start_xmit()
347 	if (active < 0 && active != -EINPROGRESS)  in bam_dmux_netdev_start_xmit()
359 		if (!atomic_long_fetch_or(BIT(skb_dma - dmux->tx_skbs),  in bam_dmux_netdev_start_xmit()
360 					  &dmux->tx_deferred_skb))  in bam_dmux_netdev_start_xmit()
361 			queue_pm_work(&dmux->tx_wakeup_work);  in bam_dmux_netdev_start_xmit()
368 	dma_async_issue_pending(dmux->tx);  in bam_dmux_netdev_start_xmit()
383 	ret = pm_runtime_resume_and_get(dmux->dev);  in bam_dmux_tx_wakeup_work()
385 		dev_err(dmux->dev, "Failed to resume: %d\n", ret);  in bam_dmux_tx_wakeup_work()
389 	pending = atomic_long_xchg(&dmux->tx_deferred_skb, 0);  in bam_dmux_tx_wakeup_work()
393 	dev_dbg(dmux->dev, "pending skbs after wakeup: %#lx\n", pending);  in bam_dmux_tx_wakeup_work()
395 		bam_dmux_skb_dma_submit_tx(&dmux->tx_skbs[i]);  in bam_dmux_tx_wakeup_work()
397 	dma_async_issue_pending(dmux->tx);  in bam_dmux_tx_wakeup_work()
400 	pm_runtime_mark_last_busy(dmux->dev);  in bam_dmux_tx_wakeup_work()
401 	pm_runtime_put_autosuspend(dmux->dev);  in bam_dmux_tx_wakeup_work()
416 	dev->netdev_ops = &bam_dmux_ops;  in bam_dmux_netdev_setup()
418 	dev->type = ARPHRD_RAWIP;  in bam_dmux_netdev_setup()
420 	dev->flags = IFF_POINTOPOINT | IFF_NOARP;  in bam_dmux_netdev_setup()
422 	dev->mtu = ETH_DATA_LEN;  in bam_dmux_netdev_setup()
423 	dev->max_mtu = BAM_DMUX_MAX_DATA_SIZE;  in bam_dmux_netdev_setup()
424 	dev->needed_headroom = sizeof(struct bam_dmux_hdr);  in bam_dmux_netdev_setup()
425 	dev->needed_tailroom = sizeof(u32); /* word-aligned */  in bam_dmux_netdev_setup()
426 	dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;  in bam_dmux_netdev_setup()
429 	dev->addr_assign_type = NET_ADDR_RANDOM;  in bam_dmux_netdev_setup()
430 	eth_random_addr(dev->perm_addr);  in bam_dmux_netdev_setup()
440 	for_each_set_bit(ch, dmux->remote_channels, BAM_DMUX_NUM_CH) {  in bam_dmux_register_netdev_work()
441 		if (dmux->netdevs[ch])  in bam_dmux_register_netdev_work()
449 		SET_NETDEV_DEV(netdev, dmux->dev);  in bam_dmux_register_netdev_work()
450 		netdev->dev_port = ch;  in bam_dmux_register_netdev_work()
453 		bndev->dmux = dmux;  in bam_dmux_register_netdev_work()
454 		bndev->ch = ch;  in bam_dmux_register_netdev_work()
458 			dev_err(dmux->dev, "Failed to register netdev for channel %u: %d\n",  in bam_dmux_register_netdev_work()
464 		dmux->netdevs[ch] = netdev;  in bam_dmux_register_netdev_work()
472 	struct bam_dmux *dmux = skb_dma->dmux;  in bam_dmux_skb_dma_submit_rx()
475 	desc = dmaengine_prep_slave_single(dmux->rx, skb_dma->addr,  in bam_dmux_skb_dma_submit_rx()
476 					   skb_dma->skb->len, DMA_DEV_TO_MEM,  in bam_dmux_skb_dma_submit_rx()
479 		dev_err(dmux->dev, "Failed to prepare RX DMA buffer\n");  in bam_dmux_skb_dma_submit_rx()
483 	desc->callback = bam_dmux_rx_callback;  in bam_dmux_skb_dma_submit_rx()
484 	desc->callback_param = skb_dma;  in bam_dmux_skb_dma_submit_rx()
485 	desc->cookie = dmaengine_submit(desc);  in bam_dmux_skb_dma_submit_rx()
491 	if (!skb_dma->skb) {  in bam_dmux_skb_dma_queue_rx()
492 		skb_dma->skb = __netdev_alloc_skb(NULL, BAM_DMUX_BUFFER_SIZE, gfp);  in bam_dmux_skb_dma_queue_rx()
493 		if (!skb_dma->skb)  in bam_dmux_skb_dma_queue_rx()
495 		skb_put(skb_dma->skb, BAM_DMUX_BUFFER_SIZE);  in bam_dmux_skb_dma_queue_rx()
504 	struct bam_dmux *dmux = skb_dma->dmux;  in bam_dmux_cmd_data()
505 	struct sk_buff *skb = skb_dma->skb;  in bam_dmux_cmd_data()
506 	struct bam_dmux_hdr *hdr = (struct bam_dmux_hdr *)skb->data;  in bam_dmux_cmd_data()
507 	struct net_device *netdev = dmux->netdevs[hdr->ch];  in bam_dmux_cmd_data()
510 		dev_warn(dmux->dev, "Data for inactive channel %u\n", hdr->ch);  in bam_dmux_cmd_data()
514 	if (hdr->len > BAM_DMUX_MAX_DATA_SIZE) {  in bam_dmux_cmd_data()
515 		dev_err(dmux->dev, "Data larger than buffer? (%u > %u)\n",  in bam_dmux_cmd_data()
516 			hdr->len, (u16)BAM_DMUX_MAX_DATA_SIZE);  in bam_dmux_cmd_data()
520 	skb_dma->skb = NULL; /* Hand over to network stack */  in bam_dmux_cmd_data()
523 	skb_trim(skb, hdr->len);  in bam_dmux_cmd_data()
524 	skb->dev = netdev;  in bam_dmux_cmd_data()
526 	/* Only Raw-IP/QMAP is supported by this driver */  in bam_dmux_cmd_data()
527 	switch (skb->data[0] & 0xf0) {  in bam_dmux_cmd_data()
529 		skb->protocol = htons(ETH_P_IP);  in bam_dmux_cmd_data()
532 		skb->protocol = htons(ETH_P_IPV6);  in bam_dmux_cmd_data()
535 		skb->protocol = htons(ETH_P_MAP);  in bam_dmux_cmd_data()
544 	struct net_device *netdev = dmux->netdevs[hdr->ch];  in bam_dmux_cmd_open()
546 	dev_dbg(dmux->dev, "open channel: %u\n", hdr->ch);  in bam_dmux_cmd_open()
548 	if (__test_and_set_bit(hdr->ch, dmux->remote_channels)) {  in bam_dmux_cmd_open()
549 		dev_warn(dmux->dev, "Channel already open: %u\n", hdr->ch);  in bam_dmux_cmd_open()
557 		schedule_work(&dmux->register_netdev_work);  in bam_dmux_cmd_open()
563 	struct net_device *netdev = dmux->netdevs[hdr->ch];  in bam_dmux_cmd_close()
565 	dev_dbg(dmux->dev, "close channel: %u\n", hdr->ch);  in bam_dmux_cmd_close()
567 	if (!__test_and_clear_bit(hdr->ch, dmux->remote_channels)) {  in bam_dmux_cmd_close()
568 		dev_err(dmux->dev, "Channel not open: %u\n", hdr->ch);  in bam_dmux_cmd_close()
579 	struct bam_dmux *dmux = skb_dma->dmux;  in bam_dmux_rx_callback()
580 	struct sk_buff *skb = skb_dma->skb;  in bam_dmux_rx_callback()
581 	struct bam_dmux_hdr *hdr = (struct bam_dmux_hdr *)skb->data;  in bam_dmux_rx_callback()
585 	if (hdr->magic != BAM_DMUX_HDR_MAGIC) {  in bam_dmux_rx_callback()
586 		dev_err(dmux->dev, "Invalid magic in header: %#x\n", hdr->magic);  in bam_dmux_rx_callback()
590 	if (hdr->ch >= BAM_DMUX_NUM_CH) {  in bam_dmux_rx_callback()
591 		dev_dbg(dmux->dev, "Unsupported channel: %u\n", hdr->ch);  in bam_dmux_rx_callback()
595 	switch (hdr->cmd) {  in bam_dmux_rx_callback()
606 		dev_err(dmux->dev, "Unsupported command %u on channel %u\n",  in bam_dmux_rx_callback()
607 			hdr->cmd, hdr->ch);  in bam_dmux_rx_callback()
613 		dma_async_issue_pending(dmux->rx);  in bam_dmux_rx_callback()
618 	struct device *dev = dmux->dev;  in bam_dmux_power_on()
625 	dmux->rx = dma_request_chan(dev, "rx");  in bam_dmux_power_on()
626 	if (IS_ERR(dmux->rx)) {  in bam_dmux_power_on()
627 		dev_err(dev, "Failed to request RX DMA channel: %pe\n", dmux->rx);  in bam_dmux_power_on()
628 		dmux->rx = NULL;  in bam_dmux_power_on()
631 	dmaengine_slave_config(dmux->rx, &dma_rx_conf);  in bam_dmux_power_on()
634 		if (!bam_dmux_skb_dma_queue_rx(&dmux->rx_skbs[i], GFP_KERNEL))  in bam_dmux_power_on()
637 	dma_async_issue_pending(dmux->rx);  in bam_dmux_power_on()
650 		if (skb_dma->addr)  in bam_dmux_free_skbs()
652 		if (skb_dma->skb) {  in bam_dmux_free_skbs()
653 			dev_kfree_skb(skb_dma->skb);  in bam_dmux_free_skbs()
654 			skb_dma->skb = NULL;  in bam_dmux_free_skbs()
661 	if (dmux->tx) {  in bam_dmux_power_off()
662 		dmaengine_terminate_sync(dmux->tx);  in bam_dmux_power_off()
663 		dma_release_channel(dmux->tx);  in bam_dmux_power_off()
664 		dmux->tx = NULL;  in bam_dmux_power_off()
667 	if (dmux->rx) {  in bam_dmux_power_off()
668 		dmaengine_terminate_sync(dmux->rx);  in bam_dmux_power_off()
669 		dma_release_channel(dmux->rx);  in bam_dmux_power_off()
670 		dmux->rx = NULL;  in bam_dmux_power_off()
673 	bam_dmux_free_skbs(dmux->rx_skbs, DMA_FROM_DEVICE);  in bam_dmux_power_off()
679 	bool new_state = !dmux->pc_state;  in bam_dmux_pc_irq()
681 	dev_dbg(dmux->dev, "pc: %u\n", new_state);  in bam_dmux_pc_irq()
693 	dmux->pc_state = new_state;  in bam_dmux_pc_irq()
694 	wake_up_all(&dmux->pc_wait);  in bam_dmux_pc_irq()
703 	dev_dbg(dmux->dev, "pc ack\n");  in bam_dmux_pc_ack_irq()
704 	complete_all(&dmux->pc_ack_completion);  in bam_dmux_pc_ack_irq()
726 	if (!wait_for_completion_timeout(&dmux->pc_ack_completion,  in bam_dmux_runtime_resume()
728 		return -ETIMEDOUT;  in bam_dmux_runtime_resume()
733 	/* Wait for ack */  in bam_dmux_runtime_resume()
734 	if (!wait_for_completion_timeout(&dmux->pc_ack_completion,  in bam_dmux_runtime_resume()
737 		return -ETIMEDOUT;  in bam_dmux_runtime_resume()
741 	if (!wait_event_timeout(dmux->pc_wait, dmux->pc_state,  in bam_dmux_runtime_resume()
744 		return -ETIMEDOUT;  in bam_dmux_runtime_resume()
748 	if (!dmux->rx) {  in bam_dmux_runtime_resume()
750 		return -ENXIO;  in bam_dmux_runtime_resume()
754 	if (dmux->tx)  in bam_dmux_runtime_resume()
757 	dmux->tx = dma_request_chan(dev, "tx");  in bam_dmux_runtime_resume()
758 	if (IS_ERR(dmux->tx)) {  in bam_dmux_runtime_resume()
759 		dev_err(dev, "Failed to request TX DMA channel: %pe\n", dmux->tx);  in bam_dmux_runtime_resume()
760 		dmux->tx = NULL;  in bam_dmux_runtime_resume()
762 		return -ENXIO;  in bam_dmux_runtime_resume()
770 	struct device *dev = &pdev->dev;  in bam_dmux_probe()
777 		return -ENOMEM;  in bam_dmux_probe()
779 	dmux->dev = dev;  in bam_dmux_probe()
782 	dmux->pc_irq = platform_get_irq_byname(pdev, "pc");  in bam_dmux_probe()
783 	if (dmux->pc_irq < 0)  in bam_dmux_probe()
784 		return dmux->pc_irq;  in bam_dmux_probe()
786 	pc_ack_irq = platform_get_irq_byname(pdev, "pc-ack");  in bam_dmux_probe()
790 	dmux->pc = devm_qcom_smem_state_get(dev, "pc", &bit);  in bam_dmux_probe()
791 	if (IS_ERR(dmux->pc))  in bam_dmux_probe()
792 		return dev_err_probe(dev, PTR_ERR(dmux->pc),  in bam_dmux_probe()
793 				     "Failed to get pc state\n");  in bam_dmux_probe()
794 	dmux->pc_mask = BIT(bit);  in bam_dmux_probe()
796 	dmux->pc_ack = devm_qcom_smem_state_get(dev, "pc-ack", &bit);  in bam_dmux_probe()
797 	if (IS_ERR(dmux->pc_ack))  in bam_dmux_probe()
798 		return dev_err_probe(dev, PTR_ERR(dmux->pc_ack),  in bam_dmux_probe()
799 				     "Failed to get pc-ack state\n");  in bam_dmux_probe()
800 	dmux->pc_ack_mask = BIT(bit);  in bam_dmux_probe()
802 	init_waitqueue_head(&dmux->pc_wait);  in bam_dmux_probe()
803 	init_completion(&dmux->pc_ack_completion);  in bam_dmux_probe()
804 	complete_all(&dmux->pc_ack_completion);  in bam_dmux_probe()
806 	spin_lock_init(&dmux->tx_lock);  in bam_dmux_probe()
807 	INIT_WORK(&dmux->tx_wakeup_work, bam_dmux_tx_wakeup_work);  in bam_dmux_probe()
808 	INIT_WORK(&dmux->register_netdev_work, bam_dmux_register_netdev_work);  in bam_dmux_probe()
811 		dmux->rx_skbs[i].dmux = dmux;  in bam_dmux_probe()
812 		dmux->tx_skbs[i].dmux = dmux;  in bam_dmux_probe()
828 	ret = devm_request_threaded_irq(dev, dmux->pc_irq, NULL, bam_dmux_pc_irq,  in bam_dmux_probe()
833 	ret = irq_get_irqchip_state(dmux->pc_irq, IRQCHIP_STATE_LINE_LEVEL,  in bam_dmux_probe()
834 				    &dmux->pc_state);  in bam_dmux_probe()
839 	if (dmux->pc_state) {  in bam_dmux_probe()
857 	struct device *dev = dmux->dev;  in bam_dmux_remove()
862 	cancel_work_sync(&dmux->register_netdev_work);  in bam_dmux_remove()
865 		if (dmux->netdevs[i])  in bam_dmux_remove()
866 			unregister_netdevice_queue(dmux->netdevs[i], &list);  in bam_dmux_remove()
869 	cancel_work_sync(&dmux->tx_wakeup_work);  in bam_dmux_remove()
878 	if (!wait_event_timeout(dmux->pc_wait, !dmux->rx, BAM_DMUX_REMOTE_TIMEOUT))  in bam_dmux_remove()
882 	disable_irq(dmux->pc_irq);  in bam_dmux_remove()
884 	bam_dmux_free_skbs(dmux->tx_skbs, DMA_TO_DEVICE);  in bam_dmux_remove()
892 	{ .compatible = "qcom,bam-dmux" },
901 		.name = "bam-dmux",
909 MODULE_DESCRIPTION("Qualcomm BAM-DMUX WWAN Network Driver");