| /* |
| * MUSB OTG driver - support for Mentor's DMA controller |
| * |
| * Copyright 2005 Mentor Graphics Corporation |
| * Copyright (C) 2005-2007 by Texas Instruments |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * version 2 as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA |
| * 02110-1301 USA |
| * |
| * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN |
| * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
| * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON |
| * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| */ |
| #include <linux/device.h> |
| #include <linux/interrupt.h> |
| #include <linux/platform_device.h> |
| #include <linux/slab.h> |
| #include "musb_core.h" |
| #include "musbhsdma.h" |
| |
| static int dma_controller_start(struct dma_controller *c) |
| { |
| /* nothing to do */ |
| return 0; |
| } |
| |
| static void dma_channel_release(struct dma_channel *channel); |
| |
| static int dma_controller_stop(struct dma_controller *c) |
| { |
| struct musb_dma_controller *controller = container_of(c, |
| struct musb_dma_controller, controller); |
| struct musb *musb = controller->private_data; |
| struct dma_channel *channel; |
| u8 bit; |
| |
| if (controller->used_channels != 0) { |
| dev_err(musb->controller, |
| "Stopping DMA controller while channel active\n"); |
| |
| for (bit = 0; bit < MUSB_HSDMA_CHANNELS; bit++) { |
| if (controller->used_channels & (1 << bit)) { |
| channel = &controller->channel[bit].channel; |
| dma_channel_release(channel); |
| |
| if (!controller->used_channels) |
| break; |
| } |
| } |
| } |
| |
| return 0; |
| } |
| |
| static struct dma_channel *dma_channel_allocate(struct dma_controller *c, |
| struct musb_hw_ep *hw_ep, u8 transmit) |
| { |
| struct musb_dma_controller *controller = container_of(c, |
| struct musb_dma_controller, controller); |
| struct musb_dma_channel *musb_channel = NULL; |
| struct dma_channel *channel = NULL; |
| u8 bit; |
| |
| for (bit = 0; bit < MUSB_HSDMA_CHANNELS; bit++) { |
| if (!(controller->used_channels & (1 << bit))) { |
| controller->used_channels |= (1 << bit); |
| musb_channel = &(controller->channel[bit]); |
| musb_channel->controller = controller; |
| musb_channel->idx = bit; |
| musb_channel->epnum = hw_ep->epnum; |
| musb_channel->transmit = transmit; |
| channel = &(musb_channel->channel); |
| channel->private_data = musb_channel; |
| channel->status = MUSB_DMA_STATUS_FREE; |
| channel->max_len = 0x10000; |
| /* Tx => mode 1; Rx => mode 0 */ |
| channel->desired_mode = transmit; |
| channel->actual_len = 0; |
| break; |
| } |
| } |
| |
| return channel; |
| } |
| |
| static void dma_channel_release(struct dma_channel *channel) |
| { |
| struct musb_dma_channel *musb_channel = channel->private_data; |
| |
| channel->actual_len = 0; |
| musb_channel->start_addr = 0; |
| musb_channel->len = 0; |
| |
| musb_channel->controller->used_channels &= |
| ~(1 << musb_channel->idx); |
| |
| channel->status = MUSB_DMA_STATUS_UNKNOWN; |
| } |
| |
| static void configure_channel(struct dma_channel *channel, |
| u16 packet_sz, u8 mode, |
| dma_addr_t dma_addr, u32 len) |
| { |
| struct musb_dma_channel *musb_channel = channel->private_data; |
| struct musb_dma_controller *controller = musb_channel->controller; |
| void __iomem *mbase = controller->base; |
| u8 bchannel = musb_channel->idx; |
| u16 csr = 0; |
| |
| DBG(4, "%p, pkt_sz %d, addr 0x%x, len %d, mode %d\n", |
| channel, packet_sz, dma_addr, len, mode); |
| |
| if (mode) { |
| csr |= 1 << MUSB_HSDMA_MODE1_SHIFT; |
| BUG_ON(len < packet_sz); |
| } |
| csr |= MUSB_HSDMA_BURSTMODE_INCR16 |
| << MUSB_HSDMA_BURSTMODE_SHIFT; |
| |
| csr |= (musb_channel->epnum << MUSB_HSDMA_ENDPOINT_SHIFT) |
| | (1 << MUSB_HSDMA_ENABLE_SHIFT) |
| | (1 << MUSB_HSDMA_IRQENABLE_SHIFT) |
| | (musb_channel->transmit |
| ? (1 << MUSB_HSDMA_TRANSMIT_SHIFT) |
| : 0); |
| |
| /* address/count */ |
| musb_write_hsdma_addr(mbase, bchannel, dma_addr); |
| musb_write_hsdma_count(mbase, bchannel, len); |
| |
| /* control (this should start things) */ |
| musb_writew(mbase, |
| MUSB_HSDMA_CHANNEL_OFFSET(bchannel, MUSB_HSDMA_CONTROL), |
| csr); |
| } |
| |
| static int dma_channel_program(struct dma_channel *channel, |
| u16 packet_sz, u8 mode, |
| dma_addr_t dma_addr, u32 len) |
| { |
| struct musb_dma_channel *musb_channel = channel->private_data; |
| |
| DBG(2, "ep%d-%s pkt_sz %d, dma_addr 0x%x length %d, mode %d\n", |
| musb_channel->epnum, |
| musb_channel->transmit ? "Tx" : "Rx", |
| packet_sz, dma_addr, len, mode); |
| |
| BUG_ON(channel->status == MUSB_DMA_STATUS_UNKNOWN || |
| channel->status == MUSB_DMA_STATUS_BUSY); |
| |
| channel->actual_len = 0; |
| musb_channel->start_addr = dma_addr; |
| musb_channel->len = len; |
| musb_channel->max_packet_sz = packet_sz; |
| channel->status = MUSB_DMA_STATUS_BUSY; |
| |
| configure_channel(channel, packet_sz, mode, dma_addr, len); |
| |
| return true; |
| } |
| |
| static int dma_channel_abort(struct dma_channel *channel) |
| { |
| struct musb_dma_channel *musb_channel = channel->private_data; |
| void __iomem *mbase = musb_channel->controller->base; |
| |
| u8 bchannel = musb_channel->idx; |
| int offset; |
| u16 csr; |
| |
| if (channel->status == MUSB_DMA_STATUS_BUSY) { |
| if (musb_channel->transmit) { |
| offset = MUSB_EP_OFFSET(musb_channel->epnum, |
| MUSB_TXCSR); |
| |
| /* |
| * The programming guide says that we must clear |
| * the DMAENAB bit before the DMAMODE bit... |
| */ |
| csr = musb_readw(mbase, offset); |
| csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB); |
| musb_writew(mbase, offset, csr); |
| csr &= ~MUSB_TXCSR_DMAMODE; |
| musb_writew(mbase, offset, csr); |
| } else { |
| offset = MUSB_EP_OFFSET(musb_channel->epnum, |
| MUSB_RXCSR); |
| |
| csr = musb_readw(mbase, offset); |
| csr &= ~(MUSB_RXCSR_AUTOCLEAR | |
| MUSB_RXCSR_DMAENAB | |
| MUSB_RXCSR_DMAMODE); |
| musb_writew(mbase, offset, csr); |
| } |
| |
| musb_writew(mbase, |
| MUSB_HSDMA_CHANNEL_OFFSET(bchannel, MUSB_HSDMA_CONTROL), |
| 0); |
| musb_write_hsdma_addr(mbase, bchannel, 0); |
| musb_write_hsdma_count(mbase, bchannel, 0); |
| channel->status = MUSB_DMA_STATUS_FREE; |
| } |
| |
| return 0; |
| } |
| |
| static irqreturn_t dma_controller_irq(int irq, void *private_data) |
| { |
| struct musb_dma_controller *controller = private_data; |
| struct musb *musb = controller->private_data; |
| struct musb_dma_channel *musb_channel; |
| struct dma_channel *channel; |
| |
| void __iomem *mbase = controller->base; |
| |
| irqreturn_t retval = IRQ_NONE; |
| |
| unsigned long flags; |
| |
| u8 bchannel; |
| u8 int_hsdma; |
| |
| u32 addr, count; |
| u16 csr; |
| |
| spin_lock_irqsave(&musb->lock, flags); |
| |
| int_hsdma = musb_readb(mbase, MUSB_HSDMA_INTR); |
| |
| #ifdef CONFIG_BLACKFIN |
| /* Clear DMA interrupt flags */ |
| musb_writeb(mbase, MUSB_HSDMA_INTR, int_hsdma); |
| #endif |
| |
| if (!int_hsdma) { |
| DBG(2, "spurious DMA irq\n"); |
| |
| for (bchannel = 0; bchannel < MUSB_HSDMA_CHANNELS; bchannel++) { |
| musb_channel = (struct musb_dma_channel *) |
| &(controller->channel[bchannel]); |
| channel = &musb_channel->channel; |
| if (channel->status == MUSB_DMA_STATUS_BUSY) { |
| count = musb_read_hsdma_count(mbase, bchannel); |
| |
| if (count == 0) |
| int_hsdma |= (1 << bchannel); |
| } |
| } |
| |
| DBG(2, "int_hsdma = 0x%x\n", int_hsdma); |
| |
| if (!int_hsdma) |
| goto done; |
| } |
| |
| for (bchannel = 0; bchannel < MUSB_HSDMA_CHANNELS; bchannel++) { |
| if (int_hsdma & (1 << bchannel)) { |
| musb_channel = (struct musb_dma_channel *) |
| &(controller->channel[bchannel]); |
| channel = &musb_channel->channel; |
| |
| csr = musb_readw(mbase, |
| MUSB_HSDMA_CHANNEL_OFFSET(bchannel, |
| MUSB_HSDMA_CONTROL)); |
| |
| if (csr & (1 << MUSB_HSDMA_BUSERROR_SHIFT)) { |
| musb_channel->channel.status = |
| MUSB_DMA_STATUS_BUS_ABORT; |
| } else { |
| u8 devctl; |
| |
| addr = musb_read_hsdma_addr(mbase, |
| bchannel); |
| channel->actual_len = addr |
| - musb_channel->start_addr; |
| |
| DBG(2, "ch %p, 0x%x -> 0x%x (%zu / %d) %s\n", |
| channel, musb_channel->start_addr, |
| addr, channel->actual_len, |
| musb_channel->len, |
| (channel->actual_len |
| < musb_channel->len) ? |
| "=> reconfig 0" : "=> complete"); |
| |
| devctl = musb_readb(mbase, MUSB_DEVCTL); |
| |
| channel->status = MUSB_DMA_STATUS_FREE; |
| |
| /* completed */ |
| if ((devctl & MUSB_DEVCTL_HM) |
| && (musb_channel->transmit) |
| && ((channel->desired_mode == 0) |
| || (channel->actual_len & |
| (musb_channel->max_packet_sz - 1))) |
| ) { |
| u8 epnum = musb_channel->epnum; |
| int offset = MUSB_EP_OFFSET(epnum, |
| MUSB_TXCSR); |
| u16 txcsr; |
| |
| /* |
| * The programming guide says that we |
| * must clear DMAENAB before DMAMODE. |
| */ |
| musb_ep_select(mbase, epnum); |
| txcsr = musb_readw(mbase, offset); |
| txcsr &= ~(MUSB_TXCSR_DMAENAB |
| | MUSB_TXCSR_AUTOSET); |
| musb_writew(mbase, offset, txcsr); |
| /* Send out the packet */ |
| txcsr &= ~MUSB_TXCSR_DMAMODE; |
| txcsr |= MUSB_TXCSR_TXPKTRDY; |
| musb_writew(mbase, offset, txcsr); |
| } |
| musb_dma_completion(musb, musb_channel->epnum, |
| musb_channel->transmit); |
| } |
| } |
| } |
| |
| retval = IRQ_HANDLED; |
| done: |
| spin_unlock_irqrestore(&musb->lock, flags); |
| return retval; |
| } |
| |
| void dma_controller_destroy(struct dma_controller *c) |
| { |
| struct musb_dma_controller *controller = container_of(c, |
| struct musb_dma_controller, controller); |
| |
| if (!controller) |
| return; |
| |
| if (controller->irq) |
| free_irq(controller->irq, c); |
| |
| kfree(controller); |
| } |
| |
| struct dma_controller *__init |
| dma_controller_create(struct musb *musb, void __iomem *base) |
| { |
| struct musb_dma_controller *controller; |
| struct device *dev = musb->controller; |
| struct platform_device *pdev = to_platform_device(dev); |
| int irq = platform_get_irq(pdev, 1); |
| |
| if (irq == 0) { |
| dev_err(dev, "No DMA interrupt line!\n"); |
| return NULL; |
| } |
| |
| controller = kzalloc(sizeof(*controller), GFP_KERNEL); |
| if (!controller) |
| return NULL; |
| |
| controller->channel_count = MUSB_HSDMA_CHANNELS; |
| controller->private_data = musb; |
| controller->base = base; |
| |
| controller->controller.start = dma_controller_start; |
| controller->controller.stop = dma_controller_stop; |
| controller->controller.channel_alloc = dma_channel_allocate; |
| controller->controller.channel_release = dma_channel_release; |
| controller->controller.channel_program = dma_channel_program; |
| controller->controller.channel_abort = dma_channel_abort; |
| |
| if (request_irq(irq, dma_controller_irq, IRQF_DISABLED, |
| dev_name(musb->controller), &controller->controller)) { |
| dev_err(dev, "request_irq %d failed!\n", irq); |
| dma_controller_destroy(&controller->controller); |
| |
| return NULL; |
| } |
| |
| controller->irq = irq; |
| |
| return &controller->controller; |
| } |