Revert "xhci: replace xhci_read_64() with readq()"

This reverts commit e8b37332.  Many xHCI
host controllers can only handle 32-bit addresses, and writing 64-bits
at a time causes them to fail.  Reading 64-bits at a time may also cause
them to return 0xffffffff, so revert this commit as well.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>

drivers/usb/host/xhci-dbg.c

@@ -203,12 +203,12 @@ void xhci_print_ir_set(struct xhci_hcd *xhci, int set_num)
 				addr, (unsigned int)temp);
 
 	addr = &ir_set->erst_base;
-	temp_64 = readq(addr);
+	temp_64 = xhci_read_64(xhci, addr);
 	xhci_dbg(xhci, "  %p: ir_set.erst_base = @%08llx\n",
 			addr, temp_64);
 
 	addr = &ir_set->erst_dequeue;
-	temp_64 = readq(addr);
+	temp_64 = xhci_read_64(xhci, addr);
 	xhci_dbg(xhci, "  %p: ir_set.erst_dequeue = @%08llx\n",
 			addr, temp_64);
 }
@@ -412,7 +412,7 @@ void xhci_dbg_cmd_ptrs(struct xhci_hcd *xhci)
 {
 	u64 val;
 
-	val = readq(&xhci->op_regs->cmd_ring);
+	val = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
 	xhci_dbg(xhci, "// xHC command ring deq ptr low bits + flags = @%08x\n",
 			lower_32_bits(val));
 	xhci_dbg(xhci, "// xHC command ring deq ptr high bits = @%08x\n",

drivers/usb/host/xhci-mem.c

@@ -1958,7 +1958,7 @@ static void xhci_set_hc_event_deq(struct xhci_hcd *xhci)
 		xhci_warn(xhci, "WARN something wrong with SW event ring "
 				"dequeue ptr.\n");
 	/* Update HC event ring dequeue pointer */
-	temp = readq(&xhci->ir_set->erst_dequeue);
+	temp = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
 	temp &= ERST_PTR_MASK;
 	/* Don't clear the EHB bit (which is RW1C) because
 	 * there might be more events to service.
@@ -2312,7 +2312,7 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 			(unsigned long long)xhci->cmd_ring->first_seg->dma);
 
 	/* Set the address in the Command Ring Control register */
-	val_64 = readq(&xhci->op_regs->cmd_ring);
+	val_64 = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
 	val_64 = (val_64 & (u64) CMD_RING_RSVD_BITS) |
 		(xhci->cmd_ring->first_seg->dma & (u64) ~CMD_RING_RSVD_BITS) |
 		xhci->cmd_ring->cycle_state;
@@ -2396,7 +2396,7 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 			"// Set ERST base address for ir_set 0 = 0x%llx",
 			(unsigned long long)xhci->erst.erst_dma_addr);
-	val_64 = readq(&xhci->ir_set->erst_base);
+	val_64 = xhci_read_64(xhci, &xhci->ir_set->erst_base);
 	val_64 &= ERST_PTR_MASK;
 	val_64 |= (xhci->erst.erst_dma_addr & (u64) ~ERST_PTR_MASK);
 	xhci_write_64(xhci, val_64, &xhci->ir_set->erst_base);

drivers/usb/host/xhci-ring.c

@@ -307,7 +307,7 @@ static int xhci_abort_cmd_ring(struct xhci_hcd *xhci)
 		return 0;
 	}
 
-	temp_64 = readq(&xhci->op_regs->cmd_ring);
+	temp_64 = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
 	if (!(temp_64 & CMD_RING_RUNNING)) {
 		xhci_dbg(xhci, "Command ring had been stopped\n");
 		return 0;
@@ -2865,7 +2865,7 @@ irqreturn_t xhci_irq(struct usb_hcd *hcd)
 		/* Clear the event handler busy flag (RW1C);
 		 * the event ring should be empty.
 		 */
-		temp_64 = readq(&xhci->ir_set->erst_dequeue);
+		temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
 		xhci_write_64(xhci, temp_64 | ERST_EHB,
 				&xhci->ir_set->erst_dequeue);
 		spin_unlock(&xhci->lock);
@@ -2879,7 +2879,7 @@ irqreturn_t xhci_irq(struct usb_hcd *hcd)
 	 */
 	while (xhci_handle_event(xhci) > 0) {}
 
-	temp_64 = readq(&xhci->ir_set->erst_dequeue);
+	temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
 	/* If necessary, update the HW's version of the event ring deq ptr. */
 	if (event_ring_deq != xhci->event_ring->dequeue) {
 		deq = xhci_trb_virt_to_dma(xhci->event_ring->deq_seg,

drivers/usb/host/xhci.c

@@ -611,7 +611,7 @@ 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_64 = readq(&xhci->ir_set->erst_dequeue);
+	temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
 	temp_64 &= ~ERST_PTR_MASK;
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 			"ERST deq = 64'h%0lx", (long unsigned int) temp_64);
@@ -756,11 +756,11 @@ static void xhci_save_registers(struct xhci_hcd *xhci)
 {
 	xhci->s3.command = readl(&xhci->op_regs->command);
 	xhci->s3.dev_nt = readl(&xhci->op_regs->dev_notification);
-	xhci->s3.dcbaa_ptr = readq(&xhci->op_regs->dcbaa_ptr);
+	xhci->s3.dcbaa_ptr = xhci_read_64(xhci, &xhci->op_regs->dcbaa_ptr);
 	xhci->s3.config_reg = readl(&xhci->op_regs->config_reg);
 	xhci->s3.erst_size = readl(&xhci->ir_set->erst_size);
-	xhci->s3.erst_base = readq(&xhci->ir_set->erst_base);
-	xhci->s3.erst_dequeue = readq(&xhci->ir_set->erst_dequeue);
+	xhci->s3.erst_base = xhci_read_64(xhci, &xhci->ir_set->erst_base);
+	xhci->s3.erst_dequeue = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
 	xhci->s3.irq_pending = readl(&xhci->ir_set->irq_pending);
 	xhci->s3.irq_control = readl(&xhci->ir_set->irq_control);
 }
@@ -783,7 +783,7 @@ static void xhci_set_cmd_ring_deq(struct xhci_hcd *xhci)
 	u64	val_64;
 
 	/* step 2: initialize command ring buffer */
-	val_64 = readq(&xhci->op_regs->cmd_ring);
+	val_64 = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
 	val_64 = (val_64 & (u64) CMD_RING_RSVD_BITS) |
 		(xhci_trb_virt_to_dma(xhci->cmd_ring->deq_seg,
 				      xhci->cmd_ring->dequeue) &
@@ -3842,7 +3842,7 @@ static int xhci_setup_device(struct usb_hcd *hcd, struct usb_device *udev,
 	if (ret) {
 		return ret;
 	}
-	temp_64 = readq(&xhci->op_regs->dcbaa_ptr);
+	temp_64 = xhci_read_64(xhci, &xhci->op_regs->dcbaa_ptr);
 	xhci_dbg_trace(xhci, trace_xhci_dbg_address,
 			"Op regs DCBAA ptr = %#016llx", temp_64);
 	xhci_dbg_trace(xhci, trace_xhci_dbg_address,

drivers/usb/host/xhci.h

@@ -28,8 +28,6 @@
 #include <linux/kernel.h>
 #include <linux/usb/hcd.h>
 
-#include <asm-generic/io-64-nonatomic-lo-hi.h>
-
 /* Code sharing between pci-quirks and xhci hcd */
 #include	"xhci-ext-caps.h"
 #include "pci-quirks.h"
@@ -1614,6 +1612,14 @@ static inline struct usb_hcd *xhci_to_hcd(struct xhci_hcd *xhci)
  * xHCI implementations that do not support 64-bit address pointers will ignore
  * the high dword, and write order is irrelevant.
  */
+static inline u64 xhci_read_64(const struct xhci_hcd *xhci,
+		__le64 __iomem *regs)
+{
+	__u32 __iomem *ptr = (__u32 __iomem *) regs;
+	u64 val_lo = readl(ptr);
+	u64 val_hi = readl(ptr + 1);
+	return val_lo + (val_hi << 32);
+}
 static inline void xhci_write_64(struct xhci_hcd *xhci,
 				 const u64 val, __le64 __iomem *regs)
 {