usb: mv_udc: Add bounce buffer

The requests sent to the controller are not properly cache aligned
most of the time, thus implement a simple bounce buffer to avoid
problem with cache.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Lei Wen <leiwen@marvell.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
This commit is contained in:
Marek Vasut 2013-07-10 03:16:43 +02:00
parent f19a343e73
commit 6dd30af0fa
2 changed files with 82 additions and 8 deletions

View file

@ -247,6 +247,71 @@ static int mv_ep_disable(struct usb_ep *ep)
return 0;
}
static int mv_bounce(struct mv_ep *ep)
{
uint32_t addr = (uint32_t)ep->req.buf;
uint32_t ba;
/* Input buffer address is not aligned. */
if (addr & (ARCH_DMA_MINALIGN - 1))
goto align;
/* Input buffer length is not aligned. */
if (ep->req.length & (ARCH_DMA_MINALIGN - 1))
goto align;
/* The buffer is well aligned, only flush cache. */
ep->b_len = ep->req.length;
ep->b_buf = ep->req.buf;
goto flush;
align:
/* Use internal buffer for small payloads. */
if (ep->req.length <= 64) {
ep->b_len = 64;
ep->b_buf = ep->b_fast;
} else {
ep->b_len = roundup(ep->req.length, ARCH_DMA_MINALIGN);
ep->b_buf = memalign(ARCH_DMA_MINALIGN, ep->b_len);
if (!ep->b_buf)
return -ENOMEM;
}
memcpy(ep->b_buf, ep->req.buf, ep->req.length);
flush:
ba = (uint32_t)ep->b_buf;
flush_dcache_range(ba, ba + ep->b_len);
return 0;
}
static void mv_debounce(struct mv_ep *ep)
{
uint32_t addr = (uint32_t)ep->req.buf;
uint32_t ba = (uint32_t)ep->b_buf;
invalidate_dcache_range(ba, ba + ep->b_len);
/* Input buffer address is not aligned. */
if (addr & (ARCH_DMA_MINALIGN - 1))
goto copy;
/* Input buffer length is not aligned. */
if (ep->req.length & (ARCH_DMA_MINALIGN - 1))
goto copy;
/* The buffer is well aligned, only invalidate cache. */
return;
copy:
memcpy(ep->req.buf, ep->b_buf, ep->req.length);
/* Large payloads use allocated buffer, free it. */
if (ep->req.length > 64)
free(ep->b_buf);
}
static int mv_ep_queue(struct usb_ep *ep,
struct usb_request *req, gfp_t gfp_flags)
{
@ -254,25 +319,27 @@ static int mv_ep_queue(struct usb_ep *ep,
struct mv_udc *udc = (struct mv_udc *)controller.ctrl->hcor;
struct ept_queue_item *item;
struct ept_queue_head *head;
unsigned phys;
int bit, num, len, in;
int bit, num, len, in, ret;
num = mv_ep->desc->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
in = (mv_ep->desc->bEndpointAddress & USB_DIR_IN) != 0;
item = mv_get_qtd(num, in);
head = mv_get_qh(num, in);
phys = (unsigned)req->buf;
len = req->length;
ret = mv_bounce(mv_ep);
if (ret)
return ret;
item->next = TERMINATE;
item->info = INFO_BYTES(len) | INFO_IOC | INFO_ACTIVE;
item->page0 = phys;
item->page1 = (phys & 0xfffff000) + 0x1000;
item->page0 = (uint32_t)mv_ep->b_buf;
item->page1 = ((uint32_t)mv_ep->b_buf & 0xfffff000) + 0x1000;
head->next = (unsigned) item;
head->info = 0;
DBG("ept%d %s queue len %x, buffer %x\n",
num, in ? "in" : "out", len, phys);
DBG("ept%d %s queue len %x, buffer %p\n",
num, in ? "in" : "out", len, mv_ep->b_buf);
if (in)
bit = EPT_TX(num);
@ -303,6 +370,9 @@ static void handle_ep_complete(struct mv_ep *ep)
num, in ? "in" : "out", item->info, item->page0);
len = (item->info >> 16) & 0x7fff;
mv_debounce(ep);
ep->req.length -= len;
DBG("ept%d %s complete %x\n",
num, in ? "in" : "out", len);

View file

@ -66,9 +66,13 @@ struct mv_udc {
struct mv_ep {
struct usb_ep ep;
struct usb_request req;
struct list_head queue;
const struct usb_endpoint_descriptor *desc;
struct usb_request req;
uint8_t *b_buf;
uint32_t b_len;
uint8_t b_fast[64] __aligned(ARCH_DMA_MINALIGN);
};
struct mv_drv {