Clarify some of the expressions in the TRB math so it is easier to see
what is being done. This reveals some errors (I think) in the math, which are
also fixed.
---
drivers/usb/host/xhci-ring.c | 31 ++++++++++++++++---------------
1 files changed, 16 insertions(+), 15 deletions(-)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index b4be841..71b8687 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2374,7 +2374,8 @@ static unsigned int count_sg_trbs_needed(struct xhci_hcd *xhci, struct urb *urb)
/* Scatter gather list entries may cross 64KB boundaries */
running_total = TRB_MAX_BUFF_SIZE -
- (sg_dma_address(sg) & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
+ (sg_dma_address(sg) & (TRB_MAX_BUFF_SIZE - 1));
+ running_total &= TRB_MAX_BUFF_SIZE - 1;
if (running_total != 0)
num_trbs++;
@@ -2404,12 +2405,12 @@ static unsigned int count_sg_trbs_needed(struct xhci_hcd *xhci, struct urb *urb)
static 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 "
+ dev_info(&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, "
+ dev_info(&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,
@@ -2540,8 +2541,7 @@ static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
sg = urb->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 = TRB_MAX_BUFF_SIZE - (addr & (TRB_MAX_BUFF_SIZE - 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;
@@ -2577,7 +2577,7 @@ static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
(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) {
+ (addr & (TRB_MAX_BUFF_SIZE - 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),
@@ -2621,7 +2621,7 @@ static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
}
trb_buff_len = TRB_MAX_BUFF_SIZE -
- (addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
+ (addr & (TRB_MAX_BUFF_SIZE - 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 =
@@ -2661,7 +2661,8 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
num_trbs = 0;
/* How much data is (potentially) left before the 64KB boundary? */
running_total = TRB_MAX_BUFF_SIZE -
- (urb->transfer_dma & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
+ (urb->transfer_dma & (TRB_MAX_BUFF_SIZE - 1));
+ running_total &= TRB_MAX_BUFF_SIZE - 1;
/* If there's some data on this 64KB chunk, or we have to send a
* zero-length transfer, we need at least one TRB
@@ -2704,8 +2705,8 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
/* How much data is in the first TRB? */
addr = (u64) urb->transfer_dma;
trb_buff_len = TRB_MAX_BUFF_SIZE -
- (urb->transfer_dma & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
- if (urb->transfer_buffer_length < trb_buff_len)
+ (urb->transfer_dma & (TRB_MAX_BUFF_SIZE - 1));
+ if (trb_buff_len > urb->transfer_buffer_length)
trb_buff_len = urb->transfer_buffer_length;
first_trb = true;
@@ -2877,8 +2878,8 @@ static int count_isoc_trbs_needed(struct xhci_hcd *xhci,
addr = (u64) (urb->transfer_dma + urb->iso_frame_desc[i].offset);
td_len = urb->iso_frame_desc[i].length;
- running_total = TRB_MAX_BUFF_SIZE -
- (addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
+ running_total = TRB_MAX_BUFF_SIZE - (addr & (TRB_MAX_BUFF_SIZE - 1));
+ running_total &= TRB_MAX_BUFF_SIZE - 1;
if (running_total != 0)
num_trbs++;
@@ -2977,7 +2978,7 @@ static int xhci_queue_isoc_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
/* Calculate TRB length */
trb_buff_len = TRB_MAX_BUFF_SIZE -
- (addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
+ (addr & (TRB_MAX_BUFF_SIZE - 1));
if (trb_buff_len > td_remain_len)
trb_buff_len = td_remain_len;
--
1.6.5.1.69.g36942
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