USB: net2280: update dma buffer allocation
This updates the code handling dma-coherent buffer allocations, basically
reusing code from the musb_hdrc driver. Instead of trying to work around two
significant limitations of the dma framework (memory wastage for buffers
smaller than a page, and inconsistency between calling context requirements
for allocation and free) this just works around one of them (the latter).
So count this as two steps forward (bugfixes: the latter issue could cause
errors on some platforms, and some MIPS changes broke code for the former),
and one step back (increasing cross-platform memory wastage).
Plus linelength and whitespace fixes; and minor data segment shrinkage.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/gadget/net2280.c b/drivers/usb/gadget/net2280.c
index 0924323..3bda37f 100644
--- a/drivers/usb/gadget/net2280.c
+++ b/drivers/usb/gadget/net2280.c
@@ -2,7 +2,7 @@
* Driver for the PLX NET2280 USB device controller.
* Specs and errata are available from <http://www.plxtech.com>.
*
- * PLX Technology Inc. (formerly NetChip Technology) supported the
+ * PLX Technology Inc. (formerly NetChip Technology) supported the
* development of this driver.
*
*
@@ -26,7 +26,8 @@
* Copyright (C) 2003 David Brownell
* Copyright (C) 2003-2005 PLX Technology, Inc.
*
- * Modified Seth Levy 2005 PLX Technology, Inc. to provide compatibility with 2282 chip
+ * Modified Seth Levy 2005 PLX Technology, Inc. to provide compatibility
+ * with 2282 chip
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -85,7 +86,7 @@
static const char driver_desc [] = DRIVER_DESC;
static const char ep0name [] = "ep0";
-static const char *ep_name [] = {
+static const char *const ep_name [] = {
ep0name,
"ep-a", "ep-b", "ep-c", "ep-d",
"ep-e", "ep-f",
@@ -225,7 +226,9 @@
if (!ep->is_in)
writel ((1 << SET_NAK_OUT_PACKETS), &ep->regs->ep_rsp);
else if (dev->pdev->device != 0x2280) {
- /* Added for 2282, Don't use nak packets on an in endpoint, this was ignored on 2280 */
+ /* Added for 2282, Don't use nak packets on an in endpoint,
+ * this was ignored on 2280
+ */
writel ((1 << CLEAR_NAK_OUT_PACKETS)
| (1 << CLEAR_NAK_OUT_PACKETS_MODE), &ep->regs->ep_rsp);
}
@@ -288,7 +291,7 @@
return -ETIMEDOUT;
}
-static struct usb_ep_ops net2280_ep_ops;
+static const struct usb_ep_ops net2280_ep_ops;
static void ep_reset (struct net2280_regs __iomem *regs, struct net2280_ep *ep)
{
@@ -449,34 +452,15 @@
/*-------------------------------------------------------------------------*/
-#undef USE_KMALLOC
-
-/* many common platforms have dma-coherent caches, which means that it's
- * safe to use kmalloc() memory for all i/o buffers without using any
- * cache flushing calls. (unless you're trying to share cache lines
- * between dma and non-dma activities, which is a slow idea in any case.)
+/*
+ * dma-coherent memory allocation (for dma-capable endpoints)
*
- * other platforms need more care, with 2.5 having a moderately general
- * solution (which falls down for allocations smaller than one page)
- * that improves significantly on the 2.4 PCI allocators by removing
- * the restriction that memory never be freed in_interrupt().
+ * NOTE: the dma_*_coherent() API calls suck. Most implementations are
+ * (a) page-oriented, so small buffers lose big; and (b) asymmetric with
+ * respect to calls with irqs disabled: alloc is safe, free is not.
+ * We currently work around (b), but not (a).
*/
-#if defined(CONFIG_X86)
-#define USE_KMALLOC
-#elif defined(CONFIG_PPC) && !defined(CONFIG_NOT_COHERENT_CACHE)
-#define USE_KMALLOC
-
-#elif defined(CONFIG_MIPS) && !defined(CONFIG_DMA_NONCOHERENT)
-#define USE_KMALLOC
-
-/* FIXME there are other cases, including an x86-64 one ... */
-#endif
-
-/* allocating buffers this way eliminates dma mapping overhead, which
- * on some platforms will mean eliminating a per-io buffer copy. with
- * some kinds of system caches, further tweaks may still be needed.
- */
static void *
net2280_alloc_buffer (
struct usb_ep *_ep,
@@ -493,43 +477,71 @@
return NULL;
*dma = DMA_ADDR_INVALID;
-#if defined(USE_KMALLOC)
- retval = kmalloc(bytes, gfp_flags);
- if (retval)
- *dma = virt_to_phys(retval);
-#else
- if (ep->dma) {
- /* the main problem with this call is that it wastes memory
- * on typical 1/N page allocations: it allocates 1-N pages.
- */
-#warning Using dma_alloc_coherent even with buffers smaller than a page.
+ if (ep->dma)
retval = dma_alloc_coherent(&ep->dev->pdev->dev,
bytes, dma, gfp_flags);
- } else
+ else
retval = kmalloc(bytes, gfp_flags);
-#endif
return retval;
}
+static DEFINE_SPINLOCK(buflock);
+static LIST_HEAD(buffers);
+
+struct free_record {
+ struct list_head list;
+ struct device *dev;
+ unsigned bytes;
+ dma_addr_t dma;
+};
+
+static void do_free(unsigned long ignored)
+{
+ spin_lock_irq(&buflock);
+ while (!list_empty(&buffers)) {
+ struct free_record *buf;
+
+ buf = list_entry(buffers.next, struct free_record, list);
+ list_del(&buf->list);
+ spin_unlock_irq(&buflock);
+
+ dma_free_coherent(buf->dev, buf->bytes, buf, buf->dma);
+
+ spin_lock_irq(&buflock);
+ }
+ spin_unlock_irq(&buflock);
+}
+
+static DECLARE_TASKLET(deferred_free, do_free, 0);
+
static void
net2280_free_buffer (
struct usb_ep *_ep,
- void *buf,
+ void *address,
dma_addr_t dma,
unsigned bytes
) {
/* free memory into the right allocator */
-#ifndef USE_KMALLOC
if (dma != DMA_ADDR_INVALID) {
struct net2280_ep *ep;
+ struct free_record *buf = address;
+ unsigned long flags;
ep = container_of(_ep, struct net2280_ep, ep);
if (!_ep)
return;
- dma_free_coherent(&ep->dev->pdev->dev, bytes, buf, dma);
+
+ ep = container_of (_ep, struct net2280_ep, ep);
+ buf->dev = &ep->dev->pdev->dev;
+ buf->bytes = bytes;
+ buf->dma = dma;
+
+ spin_lock_irqsave(&buflock, flags);
+ list_add_tail(&buf->list, &buffers);
+ tasklet_schedule(&deferred_free);
+ spin_unlock_irqrestore(&buflock, flags);
} else
-#endif
- kfree (buf);
+ kfree (address);
}
/*-------------------------------------------------------------------------*/
@@ -737,7 +749,8 @@
*/
if (ep->is_in)
dmacount |= (1 << DMA_DIRECTION);
- if ((!ep->is_in && (dmacount % ep->ep.maxpacket) != 0) || ep->dev->pdev->device != 0x2280)
+ if ((!ep->is_in && (dmacount % ep->ep.maxpacket) != 0)
+ || ep->dev->pdev->device != 0x2280)
dmacount |= (1 << END_OF_CHAIN);
req->valid = valid;
@@ -812,7 +825,7 @@
/* previous OUT packet might have been short */
if (!ep->is_in && ((tmp = readl (&ep->regs->ep_stat))
- & (1 << NAK_OUT_PACKETS)) != 0) {
+ & (1 << NAK_OUT_PACKETS)) != 0) {
writel ((1 << SHORT_PACKET_TRANSFERRED_INTERRUPT),
&ep->regs->ep_stat);
@@ -1373,7 +1386,7 @@
(void) readl (&ep->regs->ep_rsp);
}
-static struct usb_ep_ops net2280_ep_ops = {
+static const struct usb_ep_ops net2280_ep_ops = {
.enable = net2280_enable,
.disable = net2280_disable,
@@ -1631,7 +1644,7 @@
}
/* Indexed Registers */
- // none yet
+ // none yet
/* Statistics */
t = scnprintf (next, size, "\nirqs: ");
@@ -1691,11 +1704,11 @@
({ char *val;
switch (d->bmAttributes & 0x03) {
case USB_ENDPOINT_XFER_BULK:
- val = "bulk"; break;
+ val = "bulk"; break;
case USB_ENDPOINT_XFER_INT:
- val = "intr"; break;
+ val = "intr"; break;
default:
- val = "iso"; break;
+ val = "iso"; break;
}; val; }),
le16_to_cpu (d->wMaxPacketSize) & 0x1fff,
ep->dma ? "dma" : "pio", ep->fifo_size
@@ -1808,8 +1821,8 @@
* net2280_set_fifo_mode - change allocation of fifo buffers
* @gadget: access to the net2280 device that will be updated
* @mode: 0 for default, four 1kB buffers (ep-a through ep-d);
- * 1 for two 2kB buffers (ep-a and ep-b only);
- * 2 for one 2kB buffer (ep-a) and two 1kB ones (ep-b, ep-c).
+ * 1 for two 2kB buffers (ep-a and ep-b only);
+ * 2 for one 2kB buffer (ep-a) and two 1kB ones (ep-b, ep-c).
*
* returns zero on success, else negative errno. when this succeeds,
* the contents of gadget->ep_list may have changed.
@@ -2241,7 +2254,8 @@
req->td->dmacount = 0;
t = readl (&ep->regs->ep_avail);
dma_done (ep, req, count,
- (ep->out_overflow || t) ? -EOVERFLOW : 0);
+ (ep->out_overflow || t)
+ ? -EOVERFLOW : 0);
}
/* also flush to prevent erratum 0106 trouble */
@@ -2411,7 +2425,7 @@
, &ep->regs->ep_stat);
u.raw [0] = readl (&dev->usb->setup0123);
u.raw [1] = readl (&dev->usb->setup4567);
-
+
cpu_to_le32s (&u.raw [0]);
cpu_to_le32s (&u.raw [1]);
@@ -2578,14 +2592,16 @@
/* VBUS disconnect is indicated by VBUS_PIN and VBUS_INTERRUPT set.
* Root Port Reset is indicated by ROOT_PORT_RESET_INTERRRUPT set and
- * both HIGH_SPEED and FULL_SPEED clear (as ROOT_PORT_RESET_INTERRUPT
+ * both HIGH_SPEED and FULL_SPEED clear (as ROOT_PORT_RESET_INTERRUPT
* only indicates a change in the reset state).
*/
if (stat & tmp) {
writel (tmp, &dev->regs->irqstat1);
- if ((((stat & (1 << ROOT_PORT_RESET_INTERRUPT)) &&
- ((readl (&dev->usb->usbstat) & mask) == 0))
- || ((readl (&dev->usb->usbctl) & (1 << VBUS_PIN)) == 0)
+ if ((((stat & (1 << ROOT_PORT_RESET_INTERRUPT))
+ && ((readl (&dev->usb->usbstat) & mask)
+ == 0))
+ || ((readl (&dev->usb->usbctl)
+ & (1 << VBUS_PIN)) == 0)
) && ( dev->gadget.speed != USB_SPEED_UNKNOWN)) {
DEBUG (dev, "disconnect %s\n",
dev->driver->driver.name);
@@ -2852,7 +2868,7 @@
/* now all the pci goodies ... */
if (pci_enable_device (pdev) < 0) {
- retval = -ENODEV;
+ retval = -ENODEV;
goto done;
}
dev->enabled = 1;
@@ -2870,6 +2886,10 @@
}
dev->region = 1;
+ /* FIXME provide firmware download interface to put
+ * 8051 code into the chip, e.g. to turn on PCI PM.
+ */
+
base = ioremap_nocache (resource, len);
if (base == NULL) {
DEBUG (dev, "can't map memory\n");
@@ -2984,16 +3004,16 @@
/*-------------------------------------------------------------------------*/
-static struct pci_device_id pci_ids [] = { {
- .class = ((PCI_CLASS_SERIAL_USB << 8) | 0xfe),
- .class_mask = ~0,
+static const struct pci_device_id pci_ids [] = { {
+ .class = ((PCI_CLASS_SERIAL_USB << 8) | 0xfe),
+ .class_mask = ~0,
.vendor = 0x17cc,
.device = 0x2280,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
}, {
- .class = ((PCI_CLASS_SERIAL_USB << 8) | 0xfe),
- .class_mask = ~0,
+ .class = ((PCI_CLASS_SERIAL_USB << 8) | 0xfe),
+ .class_mask = ~0,
.vendor = 0x17cc,
.device = 0x2282,
.subvendor = PCI_ANY_ID,