// SPDX-License-Identifier: GPL-2.0+ /* * drivers/usb/musb/ux500_dma.c * * U8500 DMA support code * * Copyright (C) 2009 STMicroelectronics * Copyright (C) 2011 ST-Ericsson SA * Authors: * Mian Yousaf Kaukab * Praveena Nadahally * Rajaram Regupathy */ #include #include #include #include #include #include #include #include #include "musb_core.h" static const char *iep_chan_names[] = { "iep_1_9", "iep_2_10", "iep_3_11", "iep_4_12", "iep_5_13", "iep_6_14", "iep_7_15", "iep_8" }; static const char *oep_chan_names[] = { "oep_1_9", "oep_2_10", "oep_3_11", "oep_4_12", "oep_5_13", "oep_6_14", "oep_7_15", "oep_8" }; struct ux500_dma_channel { struct dma_channel channel; struct ux500_dma_controller *controller; struct musb_hw_ep *hw_ep; struct dma_chan *dma_chan; unsigned int cur_len; dma_cookie_t cookie; u8 ch_num; u8 is_tx; u8 is_allocated; }; struct ux500_dma_controller { struct dma_controller controller; struct ux500_dma_channel rx_channel[UX500_MUSB_DMA_NUM_RX_TX_CHANNELS]; struct ux500_dma_channel tx_channel[UX500_MUSB_DMA_NUM_RX_TX_CHANNELS]; void *private_data; dma_addr_t phy_base; }; /* Work function invoked from DMA callback to handle rx transfers. */ static void ux500_dma_callback(void *private_data) { struct dma_channel *channel = private_data; struct ux500_dma_channel *ux500_channel = channel->private_data; struct musb_hw_ep *hw_ep = ux500_channel->hw_ep; struct musb *musb = hw_ep->musb; unsigned long flags; dev_dbg(musb->controller, "DMA rx transfer done on hw_ep=%d\n", hw_ep->epnum); spin_lock_irqsave(&musb->lock, flags); ux500_channel->channel.actual_len = ux500_channel->cur_len; ux500_channel->channel.status = MUSB_DMA_STATUS_FREE; musb_dma_completion(musb, hw_ep->epnum, ux500_channel->is_tx); spin_unlock_irqrestore(&musb->lock, flags); } static bool ux500_configure_channel(struct dma_channel *channel, u16 packet_sz, u8 mode, dma_addr_t dma_addr, u32 len) { struct ux500_dma_channel *ux500_channel = channel->private_data; struct musb_hw_ep *hw_ep = ux500_channel->hw_ep; struct dma_chan *dma_chan = ux500_channel->dma_chan; struct dma_async_tx_descriptor *dma_desc; enum dma_transfer_direction direction; struct scatterlist sg; struct dma_slave_config slave_conf; enum dma_slave_buswidth addr_width; struct musb *musb = ux500_channel->controller->private_data; dma_addr_t usb_fifo_addr = (musb->io.fifo_offset(hw_ep->epnum) + ux500_channel->controller->phy_base); dev_dbg(musb->controller, "packet_sz=%d, mode=%d, dma_addr=0x%llx, len=%d is_tx=%d\n", packet_sz, mode, (unsigned long long) dma_addr, len, ux500_channel->is_tx); ux500_channel->cur_len = len; sg_init_table(&sg, 1); sg_set_page(&sg, pfn_to_page(PFN_DOWN(dma_addr)), len, offset_in_page(dma_addr)); sg_dma_address(&sg) = dma_addr; sg_dma_len(&sg) = len; direction = ux500_channel->is_tx ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM; addr_width = (len & 0x3) ? DMA_SLAVE_BUSWIDTH_1_BYTE : DMA_SLAVE_BUSWIDTH_4_BYTES; slave_conf.direction = direction; slave_conf.src_addr = usb_fifo_addr; slave_conf.src_addr_width = addr_width; slave_conf.src_maxburst = 16; slave_conf.dst_addr = usb_fifo_addr; slave_conf.dst_addr_width = addr_width; slave_conf.dst_maxburst = 16; slave_conf.device_fc = false; dmaengine_slave_config(dma_chan, &slave_conf); dma_desc = dmaengine_prep_slave_sg(dma_chan, &sg, 1, direction, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!dma_desc) return false; dma_desc->callback = ux500_dma_callback; dma_desc->callback_param = channel; ux500_channel->cookie = dma_desc->tx_submit(dma_desc); dma_async_issue_pending(dma_chan); return true; } static struct dma_channel *ux500_dma_channel_allocate(struct dma_controller *c, struct musb_hw_ep *hw_ep, u8 is_tx) { struct ux500_dma_controller *controller = container_of(c, struct ux500_dma_controller, controller); struct ux500_dma_channel *ux500_channel = NULL; struct musb *musb = controller->private_data; u8 ch_num = hw_ep->epnum - 1; /* 8 DMA channels (0 - 7). Each DMA channel can only be allocated * to specified hw_ep. For example DMA channel 0 can only be allocated * to hw_ep 1 and 9. */ if (ch_num > 7) ch_num -= 8; if (ch_num >= UX500_MUSB_DMA_NUM_RX_TX_CHANNELS) return NULL; ux500_channel = is_tx ? &(controller->tx_channel[ch_num]) : &(controller->rx_channel[ch_num]) ; /* Check if channel is already used. */ if (ux500_channel->is_allocated) return NULL; ux500_channel->hw_ep = hw_ep; ux500_channel->is_allocated = 1; dev_dbg(musb->controller, "hw_ep=%d, is_tx=0x%x, channel=%d\n", hw_ep->epnum, is_tx, ch_num); return &(ux500_channel->channel); } static void ux500_dma_channel_release(struct dma_channel *channel) { struct ux500_dma_channel *ux500_channel = channel->private_data; struct musb *musb = ux500_channel->controller->private_data; dev_dbg(musb->controller, "channel=%d\n", ux500_channel->ch_num); if (ux500_channel->is_allocated) { ux500_channel->is_allocated = 0; channel->status = MUSB_DMA_STATUS_FREE; channel->actual_len = 0; } } static int ux500_dma_is_compatible(struct dma_channel *channel, u16 maxpacket, void *buf, u32 length) { if ((maxpacket & 0x3) || ((unsigned long int) buf & 0x3) || (length < 512) || (length & 0x3)) return false; else return true; } static int ux500_dma_channel_program(struct dma_channel *channel, u16 packet_sz, u8 mode, dma_addr_t dma_addr, u32 len) { int ret; BUG_ON(channel->status == MUSB_DMA_STATUS_UNKNOWN || channel->status == MUSB_DMA_STATUS_BUSY); channel->status = MUSB_DMA_STATUS_BUSY; channel->actual_len = 0; ret = ux500_configure_channel(channel, packet_sz, mode, dma_addr, len); if (!ret) channel->status = MUSB_DMA_STATUS_FREE; return ret; } static int ux500_dma_channel_abort(struct dma_channel *channel) { struct ux500_dma_channel *ux500_channel = channel->private_data; struct ux500_dma_controller *controller = ux500_channel->controller; struct musb *musb = controller->private_data; void __iomem *epio = musb->endpoints[ux500_channel->hw_ep->epnum].regs; u16 csr; dev_dbg(musb->controller, "channel=%d, is_tx=%d\n", ux500_channel->ch_num, ux500_channel->is_tx); if (channel->status == MUSB_DMA_STATUS_BUSY) { if (ux500_channel->is_tx) { csr = musb_readw(epio, MUSB_TXCSR); csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB | MUSB_TXCSR_DMAMODE); musb_writew(epio, MUSB_TXCSR, csr); } else { csr = musb_readw(epio, MUSB_RXCSR); csr &= ~(MUSB_RXCSR_AUTOCLEAR | MUSB_RXCSR_DMAENAB | MUSB_RXCSR_DMAMODE); musb_writew(epio, MUSB_RXCSR, csr); } dmaengine_terminate_all(ux500_channel->dma_chan); channel->status = MUSB_DMA_STATUS_FREE; } return 0; } static void ux500_dma_controller_stop(struct ux500_dma_controller *controller) { struct ux500_dma_channel *ux500_channel; struct dma_channel *channel; u8 ch_num; for (ch_num = 0; ch_num < UX500_MUSB_DMA_NUM_RX_TX_CHANNELS; ch_num++) { channel = &controller->rx_channel[ch_num].channel; ux500_channel = channel->private_data; ux500_dma_channel_release(channel); if (ux500_channel->dma_chan) dma_release_channel(ux500_channel->dma_chan); } for (ch_num = 0; ch_num < UX500_MUSB_DMA_NUM_RX_TX_CHANNELS; ch_num++) { channel = &controller->tx_channel[ch_num].channel; ux500_channel = channel->private_data; ux500_dma_channel_release(channel); if (ux500_channel->dma_chan) dma_release_channel(ux500_channel->dma_chan); } } static int ux500_dma_controller_start(struct ux500_dma_controller *controller) { struct ux500_dma_channel *ux500_channel = NULL; struct musb *musb = controller->private_data; struct device *dev = musb->controller; struct musb_hdrc_platform_data *plat = dev_get_platdata(dev); struct ux500_musb_board_data *data; struct dma_channel *dma_channel = NULL; char **chan_names; u32 ch_num; u8 dir; u8 is_tx = 0; void **param_array; struct ux500_dma_channel *channel_array; dma_cap_mask_t mask; if (!plat) { dev_err(musb->controller, "No platform data\n"); return -EINVAL; } data = plat->board_data; dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); /* Prepare the loop for RX channels */ channel_array = controller->rx_channel; param_array = data ? data->dma_rx_param_array : NULL; chan_names = (char **)iep_chan_names; for (dir = 0; dir < 2; dir++) { for (ch_num = 0; ch_num < UX500_MUSB_DMA_NUM_RX_TX_CHANNELS; ch_num++) { ux500_channel = &channel_array[ch_num]; ux500_channel->controller = controller; ux500_channel->ch_num = ch_num; ux500_channel->is_tx = is_tx; dma_channel = &(ux500_channel->channel); dma_channel->private_data = ux500_channel; dma_channel->status = MUSB_DMA_STATUS_FREE; dma_channel->max_len = SZ_16M; ux500_channel->dma_chan = dma_request_slave_channel(dev, chan_names[ch_num]); if (!ux500_channel->dma_chan) ux500_channel->dma_chan = dma_request_channel(mask, data ? data->dma_filter : NULL, param_array ? param_array[ch_num] : NULL); if (!ux500_channel->dma_chan) { ERR("Dma pipe allocation error dir=%d ch=%d\n", dir, ch_num); /* Release already allocated channels */ ux500_dma_controller_stop(controller); return -EBUSY; } } /* Prepare the loop for TX channels */ channel_array = controller->tx_channel; param_array = data ? data->dma_tx_param_array : NULL; chan_names = (char **)oep_chan_names; is_tx = 1; } return 0; } void ux500_dma_controller_destroy(struct dma_controller *c) { struct ux500_dma_controller *controller = container_of(c, struct ux500_dma_controller, controller); ux500_dma_controller_stop(controller); kfree(controller); } EXPORT_SYMBOL_GPL(ux500_dma_controller_destroy); struct dma_controller * ux500_dma_controller_create(struct musb *musb, void __iomem *base) { struct ux500_dma_controller *controller; struct platform_device *pdev = to_platform_device(musb->controller); struct resource *iomem; int ret; controller = kzalloc(sizeof(*controller), GFP_KERNEL); if (!controller) goto kzalloc_fail; controller->private_data = musb; /* Save physical address for DMA controller. */ iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!iomem) { dev_err(musb->controller, "no memory resource defined\n"); goto plat_get_fail; } controller->phy_base = (dma_addr_t) iomem->start; controller->controller.channel_alloc = ux500_dma_channel_allocate; controller->controller.channel_release = ux500_dma_channel_release; controller->controller.channel_program = ux500_dma_channel_program; controller->controller.channel_abort = ux500_dma_channel_abort; controller->controller.is_compatible = ux500_dma_is_compatible; ret = ux500_dma_controller_start(controller); if (ret) goto plat_get_fail; return &controller->controller; plat_get_fail: kfree(controller); kzalloc_fail: return NULL; } EXPORT_SYMBOL_GPL(ux500_dma_controller_create);