forked from Minki/linux
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
155 lines
3.2 KiB
C
155 lines
3.2 KiB
C
/*
|
|
* DMA memory management for framework level HCD code (hc_driver)
|
|
*
|
|
* This implementation plugs in through generic "usb_bus" level methods,
|
|
* and should work with all USB controllers, regardles of bus type.
|
|
*/
|
|
|
|
#include <linux/config.h>
|
|
#include <linux/module.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/device.h>
|
|
#include <linux/mm.h>
|
|
#include <asm/io.h>
|
|
#include <asm/scatterlist.h>
|
|
#include <linux/dma-mapping.h>
|
|
#include <linux/dmapool.h>
|
|
|
|
|
|
#ifdef CONFIG_USB_DEBUG
|
|
#define DEBUG
|
|
#else
|
|
#undef DEBUG
|
|
#endif
|
|
|
|
#include <linux/usb.h>
|
|
#include "hcd.h"
|
|
|
|
|
|
/*
|
|
* DMA-Coherent Buffers
|
|
*/
|
|
|
|
/* FIXME tune these based on pool statistics ... */
|
|
static const size_t pool_max [HCD_BUFFER_POOLS] = {
|
|
/* platforms without dma-friendly caches might need to
|
|
* prevent cacheline sharing...
|
|
*/
|
|
32,
|
|
128,
|
|
512,
|
|
PAGE_SIZE / 2
|
|
/* bigger --> allocate pages */
|
|
};
|
|
|
|
|
|
/* SETUP primitives */
|
|
|
|
/**
|
|
* hcd_buffer_create - initialize buffer pools
|
|
* @hcd: the bus whose buffer pools are to be initialized
|
|
* Context: !in_interrupt()
|
|
*
|
|
* Call this as part of initializing a host controller that uses the dma
|
|
* memory allocators. It initializes some pools of dma-coherent memory that
|
|
* will be shared by all drivers using that controller, or returns a negative
|
|
* errno value on error.
|
|
*
|
|
* Call hcd_buffer_destroy() to clean up after using those pools.
|
|
*/
|
|
int hcd_buffer_create (struct usb_hcd *hcd)
|
|
{
|
|
char name [16];
|
|
int i, size;
|
|
|
|
for (i = 0; i < HCD_BUFFER_POOLS; i++) {
|
|
if (!(size = pool_max [i]))
|
|
continue;
|
|
snprintf (name, sizeof name, "buffer-%d", size);
|
|
hcd->pool [i] = dma_pool_create (name, hcd->self.controller,
|
|
size, size, 0);
|
|
if (!hcd->pool [i]) {
|
|
hcd_buffer_destroy (hcd);
|
|
return -ENOMEM;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
/**
|
|
* hcd_buffer_destroy - deallocate buffer pools
|
|
* @hcd: the bus whose buffer pools are to be destroyed
|
|
* Context: !in_interrupt()
|
|
*
|
|
* This frees the buffer pools created by hcd_buffer_create().
|
|
*/
|
|
void hcd_buffer_destroy (struct usb_hcd *hcd)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < HCD_BUFFER_POOLS; i++) {
|
|
struct dma_pool *pool = hcd->pool [i];
|
|
if (pool) {
|
|
dma_pool_destroy (pool);
|
|
hcd->pool[i] = NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/* sometimes alloc/free could use kmalloc with SLAB_DMA, for
|
|
* better sharing and to leverage mm/slab.c intelligence.
|
|
*/
|
|
|
|
void *hcd_buffer_alloc (
|
|
struct usb_bus *bus,
|
|
size_t size,
|
|
int mem_flags,
|
|
dma_addr_t *dma
|
|
)
|
|
{
|
|
struct usb_hcd *hcd = bus->hcpriv;
|
|
int i;
|
|
|
|
/* some USB hosts just use PIO */
|
|
if (!bus->controller->dma_mask) {
|
|
*dma = ~(dma_addr_t) 0;
|
|
return kmalloc (size, mem_flags);
|
|
}
|
|
|
|
for (i = 0; i < HCD_BUFFER_POOLS; i++) {
|
|
if (size <= pool_max [i])
|
|
return dma_pool_alloc (hcd->pool [i], mem_flags, dma);
|
|
}
|
|
return dma_alloc_coherent (hcd->self.controller, size, dma, 0);
|
|
}
|
|
|
|
void hcd_buffer_free (
|
|
struct usb_bus *bus,
|
|
size_t size,
|
|
void *addr,
|
|
dma_addr_t dma
|
|
)
|
|
{
|
|
struct usb_hcd *hcd = bus->hcpriv;
|
|
int i;
|
|
|
|
if (!addr)
|
|
return;
|
|
|
|
if (!bus->controller->dma_mask) {
|
|
kfree (addr);
|
|
return;
|
|
}
|
|
|
|
for (i = 0; i < HCD_BUFFER_POOLS; i++) {
|
|
if (size <= pool_max [i]) {
|
|
dma_pool_free (hcd->pool [i], addr, dma);
|
|
return;
|
|
}
|
|
}
|
|
dma_free_coherent (hcd->self.controller, size, addr, dma);
|
|
}
|