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yaml
---
r: 151419
b: refs/heads/master
c: 8a96c05
h: refs/heads/master
i:
  151417: c3fbee9
  151415: d9e1e76
v: v3
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Sarah Sharp authored and Greg Kroah-Hartman committed Jun 16, 2009
1 parent 09f6310 commit f9f4959
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Showing 2 changed files with 218 additions and 29 deletions.
2 changes: 1 addition & 1 deletion [refs]
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Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: e04748e3a87271fcf30d383e3780c5d3ee1c1618
refs/heads/master: 8a96c052283e68fe91a6c657c175b39bfed80bed
245 changes: 217 additions & 28 deletions trunk/drivers/usb/host/xhci-ring.c
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Original file line number Diff line number Diff line change
Expand Up @@ -64,6 +64,7 @@
* endpoint rings; it generates events on the event ring for these.
*/

#include <linux/scatterlist.h>
#include "xhci.h"

/*
Expand Down Expand Up @@ -758,6 +759,211 @@ int xhci_prepare_transfer(struct xhci_hcd *xhci,
return 0;
}

unsigned int count_sg_trbs_needed(struct xhci_hcd *xhci, struct urb *urb)
{
int num_sgs, num_trbs, running_total, temp, i;
struct scatterlist *sg;

sg = NULL;
num_sgs = urb->num_sgs;
temp = urb->transfer_buffer_length;

xhci_dbg(xhci, "count sg list trbs: \n");
num_trbs = 0;
for_each_sg(urb->sg->sg, sg, num_sgs, i) {
unsigned int previous_total_trbs = num_trbs;
unsigned int len = sg_dma_len(sg);

/* Scatter gather list entries may cross 64KB boundaries */
running_total = TRB_MAX_BUFF_SIZE -
(sg_dma_address(sg) & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
if (running_total != 0)
num_trbs++;

/* How many more 64KB chunks to transfer, how many more TRBs? */
while (running_total < sg_dma_len(sg)) {
num_trbs++;
running_total += TRB_MAX_BUFF_SIZE;
}
xhci_dbg(xhci, " sg #%d: dma = %#x, len = %#x (%d), num_trbs = %d\n",
i, sg_dma_address(sg), len, len,
num_trbs - previous_total_trbs);

len = min_t(int, len, temp);
temp -= len;
if (temp == 0)
break;
}
xhci_dbg(xhci, "\n");
if (!in_interrupt())
dev_dbg(&urb->dev->dev, "ep %#x - urb len = %d, sglist used, num_trbs = %d\n",
urb->ep->desc.bEndpointAddress,
urb->transfer_buffer_length,
num_trbs);
return num_trbs;
}

void check_trb_math(struct urb *urb, int num_trbs, int running_total)
{
if (num_trbs != 0)
dev_dbg(&urb->dev->dev, "%s - ep %#x - Miscalculated number of "
"TRBs, %d left\n", __func__,
urb->ep->desc.bEndpointAddress, num_trbs);
if (running_total != urb->transfer_buffer_length)
dev_dbg(&urb->dev->dev, "%s - ep %#x - Miscalculated tx length, "
"queued %#x (%d), asked for %#x (%d)\n",
__func__,
urb->ep->desc.bEndpointAddress,
running_total, running_total,
urb->transfer_buffer_length,
urb->transfer_buffer_length);
}

void giveback_first_trb(struct xhci_hcd *xhci, int slot_id,
unsigned int ep_index, int start_cycle,
struct xhci_generic_trb *start_trb, struct xhci_td *td)
{
u32 field;

/*
* Pass all the TRBs to the hardware at once and make sure this write
* isn't reordered.
*/
wmb();
start_trb->field[3] |= start_cycle;
field = xhci_readl(xhci, &xhci->dba->doorbell[slot_id]) & DB_MASK;
xhci_writel(xhci, field | EPI_TO_DB(ep_index),
&xhci->dba->doorbell[slot_id]);
/* Flush PCI posted writes */
xhci_readl(xhci, &xhci->dba->doorbell[slot_id]);
}

int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
struct urb *urb, int slot_id, unsigned int ep_index)
{
struct xhci_ring *ep_ring;
unsigned int num_trbs;
struct xhci_td *td;
struct scatterlist *sg;
int num_sgs;
int trb_buff_len, this_sg_len, running_total;
bool first_trb;
u64 addr;

struct xhci_generic_trb *start_trb;
int start_cycle;

ep_ring = xhci->devs[slot_id]->ep_rings[ep_index];
num_trbs = count_sg_trbs_needed(xhci, urb);
num_sgs = urb->num_sgs;

trb_buff_len = xhci_prepare_transfer(xhci, xhci->devs[slot_id],
ep_index, num_trbs, urb, &td, mem_flags);
if (trb_buff_len < 0)
return trb_buff_len;
/*
* Don't give the first TRB to the hardware (by toggling the cycle bit)
* until we've finished creating all the other TRBs. The ring's cycle
* state may change as we enqueue the other TRBs, so save it too.
*/
start_trb = &ep_ring->enqueue->generic;
start_cycle = ep_ring->cycle_state;

running_total = 0;
/*
* How much data is in the first TRB?
*
* There are three forces at work for TRB buffer pointers and lengths:
* 1. We don't want to walk off the end of this sg-list entry buffer.
* 2. The transfer length that the driver requested may be smaller than
* the amount of memory allocated for this scatter-gather list.
* 3. TRBs buffers can't cross 64KB boundaries.
*/
sg = urb->sg->sg;
addr = (u64) sg_dma_address(sg);
this_sg_len = sg_dma_len(sg);
trb_buff_len = TRB_MAX_BUFF_SIZE -
(addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
trb_buff_len = min_t(int, trb_buff_len, this_sg_len);
if (trb_buff_len > urb->transfer_buffer_length)
trb_buff_len = urb->transfer_buffer_length;
xhci_dbg(xhci, "First length to xfer from 1st sglist entry = %u\n",
trb_buff_len);

first_trb = true;
/* Queue the first TRB, even if it's zero-length */
do {
u32 field = 0;

/* Don't change the cycle bit of the first TRB until later */
if (first_trb)
first_trb = false;
else
field |= ep_ring->cycle_state;

/* Chain all the TRBs together; clear the chain bit in the last
* TRB to indicate it's the last TRB in the chain.
*/
if (num_trbs > 1) {
field |= TRB_CHAIN;
} else {
/* FIXME - add check for ZERO_PACKET flag before this */
td->last_trb = ep_ring->enqueue;
field |= TRB_IOC;
}
xhci_dbg(xhci, " sg entry: dma = %#x, len = %#x (%d), "
"64KB boundary at %#x, end dma = %#x\n",
(unsigned int) addr, trb_buff_len, trb_buff_len,
(unsigned int) (addr + TRB_MAX_BUFF_SIZE) & ~(TRB_MAX_BUFF_SIZE - 1),
(unsigned int) addr + trb_buff_len);
if (TRB_MAX_BUFF_SIZE -
(addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1)) < trb_buff_len) {
xhci_warn(xhci, "WARN: sg dma xfer crosses 64KB boundaries!\n");
xhci_dbg(xhci, "Next boundary at %#x, end dma = %#x\n",
(unsigned int) (addr + TRB_MAX_BUFF_SIZE) & ~(TRB_MAX_BUFF_SIZE - 1),
(unsigned int) addr + trb_buff_len);
}
queue_trb(xhci, ep_ring, false,
(u32) addr,
(u32) ((u64) addr >> 32),
TRB_LEN(trb_buff_len) | TRB_INTR_TARGET(0),
/* We always want to know if the TRB was short,
* or we won't get an event when it completes.
* (Unless we use event data TRBs, which are a
* waste of space and HC resources.)
*/
field | TRB_ISP | TRB_TYPE(TRB_NORMAL));
--num_trbs;
running_total += trb_buff_len;

/* Calculate length for next transfer --
* Are we done queueing all the TRBs for this sg entry?
*/
this_sg_len -= trb_buff_len;
if (this_sg_len == 0) {
--num_sgs;
if (num_sgs == 0)
break;
sg = sg_next(sg);
addr = (u64) sg_dma_address(sg);
this_sg_len = sg_dma_len(sg);
} else {
addr += trb_buff_len;
}

trb_buff_len = TRB_MAX_BUFF_SIZE -
(addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
trb_buff_len = min_t(int, trb_buff_len, this_sg_len);
if (running_total + trb_buff_len > urb->transfer_buffer_length)
trb_buff_len =
urb->transfer_buffer_length - running_total;
} while (running_total < urb->transfer_buffer_length);

check_trb_math(urb, num_trbs, running_total);
giveback_first_trb(xhci, slot_id, ep_index, start_cycle, start_trb, td);
return 0;
}

/* This is very similar to what ehci-q.c qtd_fill() does */
int queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
struct urb *urb, int slot_id, unsigned int ep_index)
Expand All @@ -773,6 +979,9 @@ int queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
int running_total, trb_buff_len, ret;
u64 addr;

if (urb->sg)
return queue_bulk_sg_tx(xhci, mem_flags, urb, slot_id, ep_index);

ep_ring = xhci->devs[slot_id]->ep_rings[ep_index];

num_trbs = 0;
Expand All @@ -793,10 +1002,13 @@ int queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
/* FIXME: this doesn't deal with URB_ZERO_PACKET - need one more */

if (!in_interrupt())
dev_dbg(&urb->dev->dev, "ep %#x - urb len = %d, addr = %#x, num_trbs = %d\n",
dev_dbg(&urb->dev->dev, "ep %#x - urb len = %#x (%d), addr = %#x, num_trbs = %d\n",
urb->ep->desc.bEndpointAddress,
urb->transfer_buffer_length, urb->transfer_dma,
urb->transfer_buffer_length,
urb->transfer_buffer_length,
urb->transfer_dma,
num_trbs);

ret = xhci_prepare_transfer(xhci, xhci->devs[slot_id], ep_index,
num_trbs, urb, &td, mem_flags);
if (ret < 0)
Expand Down Expand Up @@ -860,21 +1072,8 @@ int queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
trb_buff_len = TRB_MAX_BUFF_SIZE;
} while (running_total < urb->transfer_buffer_length);

if (num_trbs != 0)
dev_dbg(&urb->dev->dev, "%s - ep %#x - Miscalculated number of "
"TRBs, %d left\n", __FUNCTION__,
urb->ep->desc.bEndpointAddress, num_trbs);
/*
* Pass all the TRBs to the hardware at once and make sure this write
* isn't reordered.
*/
wmb();
start_trb->field[3] |= start_cycle;
field = xhci_readl(xhci, &xhci->dba->doorbell[slot_id]) & DB_MASK;
xhci_writel(xhci, field | EPI_TO_DB(ep_index), &xhci->dba->doorbell[slot_id]);
/* Flush PCI posted writes */
xhci_readl(xhci, &xhci->dba->doorbell[slot_id]);

check_trb_math(urb, num_trbs, running_total);
giveback_first_trb(xhci, slot_id, ep_index, start_cycle, start_trb, td);
return 0;
}

Expand Down Expand Up @@ -965,17 +1164,7 @@ int queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
/* Event on completion */
field | TRB_IOC | TRB_TYPE(TRB_STATUS) | ep_ring->cycle_state);

/*
* Pass all the TRBs to the hardware at once and make sure this write
* isn't reordered.
*/
wmb();
start_trb->field[3] |= start_cycle;
field = xhci_readl(xhci, &xhci->dba->doorbell[slot_id]) & DB_MASK;
xhci_writel(xhci, field | EPI_TO_DB(ep_index), &xhci->dba->doorbell[slot_id]);
/* Flush PCI posted writes */
xhci_readl(xhci, &xhci->dba->doorbell[slot_id]);

giveback_first_trb(xhci, slot_id, ep_index, start_cycle, start_trb, td);
return 0;
}

Expand Down

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