USB: xhci: Represent 64-bit addresses with one u64.

There are several xHCI data structures that use two 32-bit fields to
represent a 64-bit address.  Since some architectures don't support 64-bit
PCI writes, the fields need to be written in two 32-bit writes.  The xHCI
specification says that if a platform is incapable of generating 64-bit
writes, software must write the low 32-bits first, then the high 32-bits.
Hardware that supports 64-bit addressing will wait for the high 32-bit
write before reading the revised value, and hardware that only supports
32-bit writes will ignore the high 32-bit write.

Previous xHCI code represented 64-bit addresses with two u32 values.  This
lead to buggy code that would write the 32-bits in the wrong order, or
forget to write the upper 32-bits.  Change the two u32s to one u64 and
create a function call to write all 64-bit addresses in the proper order.
This new function could be modified in the future if all platforms support
64-bit writes.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 19 insertions, 24 deletions

diff --git a/drivers/usb/host/xhci-hcd.c b/drivers/usb/host/xhci-hcd.c
index ff99365cae42..e15773598e4e 100644
--- a/drivers/usb/host/xhci-hcd.c
+++ b/drivers/usb/host/xhci-hcd.c
@@ -226,6 +226,7 @@ int xhci_init(struct usb_hcd *hcd)
 static void xhci_work(struct xhci_hcd *xhci)
 {
         u32 temp;
+        u64 temp_64;
 
         /*
          * Clear the op reg interrupt status first,
@@ -249,8 +250,8 @@ static void xhci_work(struct xhci_hcd *xhci)
         xhci_handle_event(xhci);
 
         /* Clear the event handler busy flag; the event ring should be empty. */
-        temp = xhci_readl(xhci, &xhci->ir_set->erst_dequeue[0]);
-        xhci_writel(xhci, temp & ~ERST_EHB, &xhci->ir_set->erst_dequeue[0]);
+        temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
+        xhci_write_64(xhci, temp_64 & ~ERST_EHB, &xhci->ir_set->erst_dequeue);
         /* Flush posted writes -- FIXME is this necessary? */
         xhci_readl(xhci, &xhci->ir_set->irq_pending);
 }
@@ -295,6 +296,7 @@ void xhci_event_ring_work(unsigned long arg)
 {
         unsigned long flags;
         int temp;
+        u64 temp_64;
         struct xhci_hcd *xhci = (struct xhci_hcd *) arg;
         int i, j;
 
@@ -311,9 +313,9 @@ void xhci_event_ring_work(unsigned long arg)
         xhci_dbg(xhci, "Event ring:\n");
         xhci_debug_segment(xhci, xhci->event_ring->deq_seg);
         xhci_dbg_ring_ptrs(xhci, xhci->event_ring);
-        temp = xhci_readl(xhci, &xhci->ir_set->erst_dequeue[0]);
-        temp &= ERST_PTR_MASK;
-        xhci_dbg(xhci, "ERST deq = 0x%x\n", temp);
+        temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
+        temp_64 &= ~ERST_PTR_MASK;
+        xhci_dbg(xhci, "ERST deq = 64'h%0lx\n", (long unsigned int) temp_64);
         xhci_dbg(xhci, "Command ring:\n");
         xhci_debug_segment(xhci, xhci->cmd_ring->deq_seg);
         xhci_dbg_ring_ptrs(xhci, xhci->cmd_ring);
@@ -356,6 +358,7 @@ void xhci_event_ring_work(unsigned long arg)
 int xhci_run(struct usb_hcd *hcd)
 {
         u32 temp;
+        u64 temp_64;
         struct xhci_hcd *xhci = hcd_to_xhci(hcd);
         void (*doorbell)(struct xhci_hcd *) = NULL;
 
@@ -416,11 +419,9 @@ int xhci_run(struct usb_hcd *hcd)
         xhci_dbg(xhci, "Event ring:\n");
         xhci_debug_ring(xhci, xhci->event_ring);
         xhci_dbg_ring_ptrs(xhci, xhci->event_ring);
-        temp = xhci_readl(xhci, &xhci->ir_set->erst_dequeue[0]);
-        temp &= ERST_PTR_MASK;
-        xhci_dbg(xhci, "ERST deq = 0x%x\n", temp);
-        temp = xhci_readl(xhci, &xhci->ir_set->erst_dequeue[1]);
-        xhci_dbg(xhci, "ERST deq upper = 0x%x\n", temp);
+        temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
+        temp_64 &= ~ERST_PTR_MASK;
+        xhci_dbg(xhci, "ERST deq = 64'h%0lx\n", (long unsigned int) temp_64);
 
         temp = xhci_readl(xhci, &xhci->op_regs->command);
         temp |= (CMD_RUN);
@@ -888,8 +889,7 @@ static void xhci_zero_in_ctx(struct xhci_virt_device *virt_dev)
                 ep_ctx = &virt_dev->in_ctx->ep[i];
                 ep_ctx->ep_info = 0;
                 ep_ctx->ep_info2 = 0;
-                ep_ctx->deq[0] = 0;
-                ep_ctx->deq[1] = 0;
+                ep_ctx->deq = 0;
                 ep_ctx->tx_info = 0;
         }
 }
@@ -1165,7 +1165,7 @@ int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev)
         struct xhci_virt_device *virt_dev;
         int ret = 0;
         struct xhci_hcd *xhci = hcd_to_xhci(hcd);
-        u32 temp;
+        u64 temp_64;
 
         if (!udev->slot_id) {
                 xhci_dbg(xhci, "Bad Slot ID %d\n", udev->slot_id);
@@ -1227,18 +1227,13 @@ int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev)
         if (ret) {
                 return ret;
         }
-        temp = xhci_readl(xhci, &xhci->op_regs->dcbaa_ptr[0]);
-        xhci_dbg(xhci, "Op regs DCBAA ptr[0] = %#08x\n", temp);
-        temp = xhci_readl(xhci, &xhci->op_regs->dcbaa_ptr[1]);
-        xhci_dbg(xhci, "Op regs DCBAA ptr[1] = %#08x\n", temp);
-        xhci_dbg(xhci, "Slot ID %d dcbaa entry[0] @%p = %#08x\n",
-                        udev->slot_id,
-                        &xhci->dcbaa->dev_context_ptrs[2*udev->slot_id],
-                        xhci->dcbaa->dev_context_ptrs[2*udev->slot_id]);
-        xhci_dbg(xhci, "Slot ID %d dcbaa entry[1] @%p = %#08x\n",
+        temp_64 = xhci_read_64(xhci, &xhci->op_regs->dcbaa_ptr);
+        xhci_dbg(xhci, "Op regs DCBAA ptr = %#016llx\n", temp_64);
+        xhci_dbg(xhci, "Slot ID %d dcbaa entry @%p = %#016llx\n",
                         udev->slot_id,
-                        &xhci->dcbaa->dev_context_ptrs[2*udev->slot_id+1],
-                        xhci->dcbaa->dev_context_ptrs[2*udev->slot_id+1]);
+                        &xhci->dcbaa->dev_context_ptrs[udev->slot_id],
+                        (unsigned long long)
+                                xhci->dcbaa->dev_context_ptrs[udev->slot_id]);
         xhci_dbg(xhci, "Output Context DMA address = %#08llx\n",
                         (unsigned long long)virt_dev->out_ctx_dma);
         xhci_dbg(xhci, "Slot ID %d Input Context:\n", udev->slot_id);