xhci: add xhci_address_ctx trace event

This patch defines a new event class, called xhci_log_ctx,
that records in the ring buffer the context data, the
context type (input or output), the context dma and virtual
addresses, the context endpoint entries, the slot ID and
whether the xHC uses 64 byte context data structures.

This information can be used, later, to parse and display
the context data fields with the appropriate plugin using
the trace-cmd tool.

Also, this patch defines a trace event, called xhci_address_ctx,
to trace the contexts related to the Address Device command and
adds the associated tracepoints in xhci_address_device().
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

drivers/usb/host/xhci-trace.h

@@ -18,6 +18,7 @@
 #define __XHCI_TRACE_H
 
 #include <linux/tracepoint.h>
+#include "xhci.h"
 
 #define XHCI_MSG_MAX	500
 
@@ -51,6 +52,47 @@ DEFINE_EVENT(xhci_log_msg, xhci_dbg_reset_ep,
 	TP_ARGS(vaf)
 );
 
+DECLARE_EVENT_CLASS(xhci_log_ctx,
+	TP_PROTO(struct xhci_hcd *xhci, struct xhci_container_ctx *ctx,
+		 unsigned int ep_num),
+	TP_ARGS(xhci, ctx, ep_num),
+	TP_STRUCT__entry(
+		__field(int, ctx_64)
+		__field(unsigned, ctx_type)
+		__field(dma_addr_t, ctx_dma)
+		__field(u8 *, ctx_va)
+		__field(unsigned, ctx_ep_num)
+		__field(int, slot_id)
+		__dynamic_array(u32, ctx_data,
+			((HCC_64BYTE_CONTEXT(xhci->hcc_params) + 1) * 8) *
+			((ctx->type == XHCI_CTX_TYPE_INPUT) + ep_num + 1))
+	),
+	TP_fast_assign(
+		struct usb_device *udev;
+
+		udev = to_usb_device(xhci_to_hcd(xhci)->self.controller);
+		__entry->ctx_64 = HCC_64BYTE_CONTEXT(xhci->hcc_params);
+		__entry->ctx_type = ctx->type;
+		__entry->ctx_dma = ctx->dma;
+		__entry->ctx_va = ctx->bytes;
+		__entry->slot_id = udev->slot_id;
+		__entry->ctx_ep_num = ep_num;
+		memcpy(__get_dynamic_array(ctx_data), ctx->bytes,
+			((HCC_64BYTE_CONTEXT(xhci->hcc_params) + 1) * 32) *
+			((ctx->type == XHCI_CTX_TYPE_INPUT) + ep_num + 1));
+	),
+	TP_printk("\nctx_64=%d, ctx_type=%u, ctx_dma=@%llx, ctx_va=@%p",
+			__entry->ctx_64, __entry->ctx_type,
+			(unsigned long long) __entry->ctx_dma, __entry->ctx_va
+	)
+);
+
+DEFINE_EVENT(xhci_log_ctx, xhci_address_ctx,
+	TP_PROTO(struct xhci_hcd *xhci, struct xhci_container_ctx *ctx,
+		 unsigned int ep_num),
+	TP_ARGS(xhci, ctx, ep_num)
+);
+
 #endif /* __XHCI_TRACE_H */
 
 /* this part must be outside header guard */

drivers/usb/host/xhci.c

@@ -3738,6 +3738,8 @@ int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev)
 
 	xhci_dbg(xhci, "Slot ID %d Input Context:\n", udev->slot_id);
 	xhci_dbg_ctx(xhci, virt_dev->in_ctx, 2);
+	trace_xhci_address_ctx(xhci, virt_dev->in_ctx,
+				slot_ctx->dev_info >> 27);
 
 	spin_lock_irqsave(&xhci->lock, flags);
 	cmd_trb = xhci->cmd_ring->dequeue;
@@ -3794,6 +3796,7 @@ int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev)
 				"code 0x%x.\n", virt_dev->cmd_status);
 		xhci_dbg(xhci, "Slot ID %d Output Context:\n", udev->slot_id);
 		xhci_dbg_ctx(xhci, virt_dev->out_ctx, 2);
+		trace_xhci_address_ctx(xhci, virt_dev->out_ctx, 1);
 		ret = -EINVAL;
 		break;
 	}
@@ -3814,6 +3817,8 @@ int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev)
 			(unsigned long long)virt_dev->out_ctx->dma);
 	xhci_dbg(xhci, "Slot ID %d Input Context:\n", udev->slot_id);
 	xhci_dbg_ctx(xhci, virt_dev->in_ctx, 2);
+	trace_xhci_address_ctx(xhci, virt_dev->in_ctx,
+				slot_ctx->dev_info >> 27);
 	xhci_dbg(xhci, "Slot ID %d Output Context:\n", udev->slot_id);
 	xhci_dbg_ctx(xhci, virt_dev->out_ctx, 2);
 	/*
@@ -3821,6 +3826,8 @@ int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev)
 	 * address given back to us by the HC.
 	 */
 	slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->out_ctx);
+	trace_xhci_address_ctx(xhci, virt_dev->out_ctx,
+				slot_ctx->dev_info >> 27);
 	/* Use kernel assigned address for devices; store xHC assigned
 	 * address locally. */
 	virt_dev->address = (le32_to_cpu(slot_ctx->dev_state) & DEV_ADDR_MASK)