Commit adf7d73f authored by David Brownell's avatar David Brownell Committed by Paul Mackerras

[PATCH] USB: minor net2280 cleanup

This holds minor net2280 cleanups:

  - Cleaner handling for cases where dma_alloc_coherent() must be
    used instead of kmalloc().  (Kmalloc is more memory-efficient
    for the "small buffers" case.)   Both MIPS cases should work,
    as well as others.

  - Prefetch cachelines on PIO paths.

The first of those gets rid of one <linux/version.h> usage, no
longer useful now that 2.4 and 2.6 versions have forked.
parent d0a2fba8
......@@ -50,7 +50,6 @@
#define DEBUG 1
// #define VERBOSE /* extra debug messages (success too) */
#include <linux/version.h>
#include <linux/config.h>
#include <linux/module.h>
#include <linux/pci.h>
......@@ -431,6 +430,9 @@ net2280_free_request (struct usb_ep *_ep, struct usb_request *_req)
#elif defined(CONFIG_PPC) && !defined(CONFIG_NOT_COHERENT_CACHE)
#define USE_KMALLOC
#elif defined(CONFIG_MIPS) && !defined(CONFIG_NONCOHERENT_IO)
#define USE_KMALLOC
/* FIXME there are other cases, including an x86-64 one ... */
#endif
......@@ -452,31 +454,23 @@ net2280_alloc_buffer (
ep = container_of (_ep, struct net2280_ep, ep);
if (!_ep)
return 0;
*dma = DMA_ADDR_INVALID;
if (ep->dma) {
#if defined(USE_KMALLOC)
retval = kmalloc (bytes, gfp_flags);
retval = kmalloc(bytes, gfp_flags);
if (retval)
*dma = virt_to_phys (retval);
#elif LINUX_VERSION_CODE > KERNEL_VERSION(2,5,58)
#warning Using dma_alloc_consistent even with sub-page allocations
*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.
*/
retval = dma_alloc_coherent (&ep->dev->pdev->dev,
#warning Using dma_alloc_coherent even with buffers smaller than a page.
retval = dma_alloc_coherent(&ep->dev->pdev->dev,
bytes, dma, gfp_flags);
#else
#error No dma-coherent memory allocator is available
/* pci_alloc_consistent works, but pci_free_consistent()
* isn't safe in_interrupt(). plus, in addition to the
* 1/Nth page weakness, it doesn't understand gfp_flags.
*/
#endif
} else
retval = kmalloc (bytes, gfp_flags);
retval = kmalloc(bytes, gfp_flags);
#endif
return retval;
}
......@@ -489,9 +483,14 @@ net2280_free_buffer (
) {
/* free memory into the right allocator */
#ifndef USE_KMALLOC
if (dma != DMA_ADDR_INVALID)
dma_free_coherent (ep->dev->pdev, bytes, dma);
else
if (dma != DMA_ADDR_INVALID) {
struct net2280_ep *ep;
ep = container_of(_ep, struct net2280_ep, ep);
if (!_ep)
return;
dma_free_coherent(&ep->dev->pdev->dev, bytes, buf, dma);
} else
#endif
kfree (buf);
}
......@@ -516,8 +515,9 @@ write_fifo (struct net2280_ep *ep, struct usb_request *req)
/* INVARIANT: fifo is currently empty. (testable) */
if (req) {
total = req->length - req->actual;
buf = req->buf + req->actual;
prefetch (buf);
total = req->length - req->actual;
} else {
total = 0;
buf = 0;
......@@ -615,6 +615,7 @@ read_fifo (struct net2280_ep *ep, struct net2280_request *req)
/* never overflow the rx buffer. the fifo reads packets until
* it sees a short one; we might not be ready for them all.
*/
prefetchw (buf);
count = readl (&regs->ep_avail);
tmp = req->req.length - req->req.actual;
if (count > tmp) {
......
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