--- /dev/null
+/*
+ * 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 void dma_channel_release(struct dma_channel *channel);
+
+static void dma_controller_stop(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;
+ }
+ }
+ }
+}
+
+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 = 0x100000;
+ /* 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;
+ struct musb *musb = controller->private_data;
+ void __iomem *mbase = controller->base;
+ u8 bchannel = musb_channel->idx;
+ u16 csr = 0;
+
+ dev_dbg(musb->controller, "%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;
+ struct musb_dma_controller *controller = musb_channel->controller;
+ struct musb *musb = controller->private_data;
+
+ dev_dbg(musb->controller, "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);
+
+ /* Let targets check/tweak the arguments */
+ if (musb->ops->adjust_channel_params) {
+ int ret = musb->ops->adjust_channel_params(channel,
+ packet_sz, &mode, &dma_addr, &len);
+ if (ret)
+ return ret;
+ }
+
+ /*
+ * The DMA engine in RTL1.8 and above cannot handle
+ * DMA addresses that are not aligned to a 4 byte boundary.
+ * It ends up masking the last two bits of the address
+ * programmed in DMA_ADDR.
+ *
+ * Fail such DMA transfers, so that the backup PIO mode
+ * can carry out the transfer
+ */
+ if ((musb->hwvers >= MUSB_HWVERS_1800) && (dma_addr % 4))
+ return false;
+
+ 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;
+ struct musb *musb = musb_channel->controller->private_data;
+
+ u8 bchannel = musb_channel->idx;
+ int offset;
+ u16 csr;
+
+ if (channel->status == MUSB_DMA_STATUS_BUSY) {
+ if (musb_channel->transmit) {
+ offset = musb->io.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->io.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) {
+ dev_dbg(musb->controller, "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);
+ }
+ }
+
+ dev_dbg(musb->controller, "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;
+
+ dev_dbg(musb->controller, "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->io.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);
+
+ dma_controller_stop(controller);
+
+ if (controller->irq)
+ free_irq(controller->irq, c);
+
+ kfree(controller);
+}
+
+struct dma_controller *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_byname(pdev, "dma");
+
+ 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.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, 0,
+ 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;
+}
Code Review / kvmfornfv.git / blobdiff