From 906641980c3ae4e4175268168897ebdc7314c73c Mon Sep 17 00:00:00 2001 From: Ricardo Ribalda Delgado Date: Fri, 28 Nov 2014 14:50:46 +0100 Subject: [PATCH] usb: gadget: udc: net2280: Remove obsolete module param use_dma_chaining use_dma_chaining module parameter was designed to avoid creating one irq per package on a group of packages (with the help of the driver's flag no_interrupt). Unfortunately, when this parameter is enabled, the driver fails to work on both net2280 and 3380 chips. This patch removes this parameter, which was disabled by default. Signed-off-by: Ricardo Ribalda Delgado Signed-off-by: Felipe Balbi --- drivers/usb/gadget/udc/net2280.c | 147 ++++----------------------------------- 1 file changed, 13 insertions(+), 134 deletions(-) diff --git a/drivers/usb/gadget/udc/net2280.c b/drivers/usb/gadget/udc/net2280.c index d6411e0a8e03..08c16ee092f2 100644 --- a/drivers/usb/gadget/udc/net2280.c +++ b/drivers/usb/gadget/udc/net2280.c @@ -12,11 +12,7 @@ * the Mass Storage, Serial, and Ethernet/RNDIS gadget drivers * as well as Gadget Zero and Gadgetfs. * - * DMA is enabled by default. Drivers using transfer queues might use - * DMA chaining to remove IRQ latencies between transfers. (Except when - * short OUT transfers happen.) Drivers can use the req->no_interrupt - * hint to completely eliminate some IRQs, if a later IRQ is guaranteed - * and DMA chaining is enabled. + * DMA is enabled by default. * * MSI is enabled by default. The legacy IRQ is used if MSI couldn't * be enabled. @@ -85,7 +81,6 @@ static const char *const ep_name[] = { }; /* use_dma -- general goodness, fewer interrupts, less cpu load (vs PIO) - * use_dma_chaining -- dma descriptor queueing gives even more irq reduction * * The net2280 DMA engines are not tightly integrated with their FIFOs; * not all cases are (yet) handled well in this driver or the silicon. @@ -93,12 +88,10 @@ static const char *const ep_name[] = { * These two parameters let you use PIO or more aggressive DMA. */ static bool use_dma = true; -static bool use_dma_chaining; static bool use_msi = true; /* "modprobe net2280 use_dma=n" etc */ module_param(use_dma, bool, 0444); -module_param(use_dma_chaining, bool, 0444); module_param(use_msi, bool, 0444); /* mode 0 == ep-{a,b,c,d} 1K fifo each @@ -202,15 +195,6 @@ net2280_enable(struct usb_ep *_ep, const struct usb_endpoint_descriptor *desc) /* set speed-dependent max packet; may kick in high bandwidth */ set_max_speed(ep, max); - /* FIFO lines can't go to different packets. PIO is ok, so - * use it instead of troublesome (non-bulk) multi-packet DMA. - */ - if (ep->dma && (max % 4) != 0 && use_dma_chaining) { - ep_dbg(ep->dev, "%s, no dma for maxpacket %d\n", - ep->ep.name, ep->ep.maxpacket); - ep->dma = NULL; - } - /* set type, direction, address; reset fifo counters */ writel(BIT(FIFO_FLUSH), &ep->regs->ep_stat); tmp = (desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK); @@ -747,8 +731,7 @@ static void fill_dma_desc(struct net2280_ep *ep, req->valid = valid; if (valid) dmacount |= BIT(VALID_BIT); - if (likely(!req->req.no_interrupt || !use_dma_chaining)) - dmacount |= BIT(DMA_DONE_INTERRUPT_ENABLE); + dmacount |= BIT(DMA_DONE_INTERRUPT_ENABLE); /* td->dmadesc = previously set by caller */ td->dmaaddr = cpu_to_le32 (req->req.dma); @@ -862,8 +845,7 @@ static void start_dma(struct net2280_ep *ep, struct net2280_request *req) req->td->dmadesc = cpu_to_le32 (ep->td_dma); fill_dma_desc(ep, req, 1); - if (!use_dma_chaining) - req->td->dmacount |= cpu_to_le32(BIT(END_OF_CHAIN)); + req->td->dmacount |= cpu_to_le32(BIT(END_OF_CHAIN)); start_queue(ep, tmp, req->td_dma); } @@ -1150,64 +1132,12 @@ static void scan_dma_completions(struct net2280_ep *ep) static void restart_dma(struct net2280_ep *ep) { struct net2280_request *req; - u32 dmactl = dmactl_default; if (ep->stopped) return; req = list_entry(ep->queue.next, struct net2280_request, queue); - if (!use_dma_chaining) { - start_dma(ep, req); - return; - } - - /* the 2280 will be processing the queue unless queue hiccups after - * the previous transfer: - * IN: wanted automagic zlp, head doesn't (or vice versa) - * DMA_FIFO_VALIDATE doesn't init from dma descriptors. - * OUT: was "usb-short", we must restart. - */ - if (ep->is_in && !req->valid) { - struct net2280_request *entry, *prev = NULL; - int reqmode, done = 0; - - ep_dbg(ep->dev, "%s dma hiccup td %p\n", ep->ep.name, req->td); - ep->in_fifo_validate = likely(req->req.zero || - (req->req.length % ep->ep.maxpacket) != 0); - if (ep->in_fifo_validate) - dmactl |= BIT(DMA_FIFO_VALIDATE); - list_for_each_entry(entry, &ep->queue, queue) { - __le32 dmacount; - - if (entry == req) - continue; - dmacount = entry->td->dmacount; - if (!done) { - reqmode = likely(entry->req.zero || - (entry->req.length % ep->ep.maxpacket)); - if (reqmode == ep->in_fifo_validate) { - entry->valid = 1; - dmacount |= valid_bit; - entry->td->dmacount = dmacount; - prev = entry; - continue; - } else { - /* force a hiccup */ - prev->td->dmacount |= dma_done_ie; - done = 1; - } - } - - /* walk the rest of the queue so unlinks behave */ - entry->valid = 0; - dmacount &= ~valid_bit; - entry->td->dmacount = dmacount; - prev = entry; - } - } - - writel(0, &ep->dma->dmactl); - start_queue(ep, dmactl, req->td_dma); + start_dma(ep, req); } static void abort_dma_228x(struct net2280_ep *ep) @@ -1306,25 +1236,6 @@ static int net2280_dequeue(struct usb_ep *_ep, struct usb_request *_req) done(ep, req, -ECONNRESET); } req = NULL; - - /* patch up hardware chaining data */ - } else if (ep->dma && use_dma_chaining) { - if (req->queue.prev == ep->queue.next) { - writel(le32_to_cpu(req->td->dmadesc), - &ep->dma->dmadesc); - if (req->td->dmacount & dma_done_ie) - writel(readl(&ep->dma->dmacount) | - le32_to_cpu(dma_done_ie), - &ep->dma->dmacount); - } else { - struct net2280_request *prev; - - prev = list_entry(req->queue.prev, - struct net2280_request, queue); - prev->td->dmadesc = req->td->dmadesc; - if (req->td->dmacount & dma_done_ie) - prev->td->dmacount |= dma_done_ie; - } } if (req) @@ -1609,9 +1520,7 @@ static ssize_t registers_show(struct device *_dev, "pci irqenb0 %02x irqenb1 %08x " "irqstat0 %04x irqstat1 %08x\n", driver_name, dev->chiprev, - use_dma - ? (use_dma_chaining ? "chaining" : "enabled") - : "disabled", + use_dma ? "enabled" : "disabled", readl(&dev->regs->devinit), readl(&dev->regs->fifoctl), s, @@ -3423,17 +3332,12 @@ static void handle_stat1_irqs(struct net2280 *dev, u32 stat) continue; } - /* chaining should stop on abort, short OUT from fifo, - * or (stat0 codepath) short OUT transfer. - */ - if (!use_dma_chaining) { - if (!(tmp & BIT(DMA_TRANSACTION_DONE_INTERRUPT))) { - ep_dbg(ep->dev, "%s no xact done? %08x\n", - ep->ep.name, tmp); - continue; - } - stop_dma(ep->dma); + if (!(tmp & BIT(DMA_TRANSACTION_DONE_INTERRUPT))) { + ep_dbg(ep->dev, "%s no xact done? %08x\n", + ep->ep.name, tmp); + continue; } + stop_dma(ep->dma); /* OUT transfers terminate when the data from the * host is in our memory. Process whatever's done. @@ -3448,30 +3352,9 @@ static void handle_stat1_irqs(struct net2280 *dev, u32 stat) scan_dma_completions(ep); /* disable dma on inactive queues; else maybe restart */ - if (list_empty(&ep->queue)) { - if (use_dma_chaining) - stop_dma(ep->dma); - } else { + if (!list_empty(&ep->queue)) { tmp = readl(&dma->dmactl); - if (!use_dma_chaining || (tmp & BIT(DMA_ENABLE)) == 0) - restart_dma(ep); - else if (ep->is_in && use_dma_chaining) { - struct net2280_request *req; - __le32 dmacount; - - /* the descriptor at the head of the chain - * may still have VALID_BIT clear; that's - * used to trigger changing DMA_FIFO_VALIDATE - * (affects automagic zlp writes). - */ - req = list_entry(ep->queue.next, - struct net2280_request, queue); - dmacount = req->td->dmacount; - dmacount &= cpu_to_le32(BIT(VALID_BIT) | - DMA_BYTE_COUNT_MASK); - if (dmacount && (dmacount & valid_bit) == 0) - restart_dma(ep); - } + restart_dma(ep); } ep->irqs++; } @@ -3581,9 +3464,6 @@ static int net2280_probe(struct pci_dev *pdev, const struct pci_device_id *id) void __iomem *base = NULL; int retval, i; - if (!use_dma) - use_dma_chaining = 0; - /* alloc, and start init */ dev = kzalloc(sizeof(*dev), GFP_KERNEL); if (dev == NULL) { @@ -3742,8 +3622,7 @@ static int net2280_probe(struct pci_dev *pdev, const struct pci_device_id *id) ep_info(dev, "irq %d, pci mem %p, chip rev %04x\n", pdev->irq, base, dev->chiprev); ep_info(dev, "version: " DRIVER_VERSION "; dma %s %s\n", - use_dma ? (use_dma_chaining ? "chaining" : "enabled") - : "disabled", + use_dma ? "enabled" : "disabled", dev->enhanced_mode ? "enhanced mode" : "legacy mode"); retval = device_create_file(&pdev->dev, &dev_attr_registers); if (retval) -- 2.11.0