6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Mathias Nyman mathias.nyman@linux.intel.com
[ Upstream commit 220a0ffde02f962c13bc752b01aa570b8c65a37b ]
Decouple allocation of endpoint ring buffer from initialization of the buffer, and initialization of endpoint context parts from from the rest of the contexts.
It allows driver to clear up and reinitialize endpoint rings after disconnect without reallocating everything.
This is a prerequisite for the next patch that prevents the transfer ring from filling up with cancelled (no-op) TRBs if a debug cable is reconnected several times without transferring anything.
Cc: stable@vger.kernel.org Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Link: https://lore.kernel.org/r/20250902105306.877476-2-mathias.nyman@linux.intel.... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/host/xhci-dbgcap.c | 71 ++++++++++++++++++++++++++--------------- 1 file changed, 46 insertions(+), 25 deletions(-)
--- a/drivers/usb/host/xhci-dbgcap.c +++ b/drivers/usb/host/xhci-dbgcap.c @@ -86,13 +86,34 @@ static u32 xhci_dbc_populate_strings(str return string_length; }
+static void xhci_dbc_init_ep_contexts(struct xhci_dbc *dbc) +{ + struct xhci_ep_ctx *ep_ctx; + unsigned int max_burst; + dma_addr_t deq; + + max_burst = DBC_CTRL_MAXBURST(readl(&dbc->regs->control)); + + /* Populate bulk out endpoint context: */ + ep_ctx = dbc_bulkout_ctx(dbc); + deq = dbc_bulkout_enq(dbc); + ep_ctx->ep_info = 0; + ep_ctx->ep_info2 = dbc_epctx_info2(BULK_OUT_EP, 1024, max_burst); + ep_ctx->deq = cpu_to_le64(deq | dbc->ring_out->cycle_state); + + /* Populate bulk in endpoint context: */ + ep_ctx = dbc_bulkin_ctx(dbc); + deq = dbc_bulkin_enq(dbc); + ep_ctx->ep_info = 0; + ep_ctx->ep_info2 = dbc_epctx_info2(BULK_IN_EP, 1024, max_burst); + ep_ctx->deq = cpu_to_le64(deq | dbc->ring_in->cycle_state); +} + static void xhci_dbc_init_contexts(struct xhci_dbc *dbc, u32 string_length) { struct dbc_info_context *info; - struct xhci_ep_ctx *ep_ctx; u32 dev_info; - dma_addr_t deq, dma; - unsigned int max_burst; + dma_addr_t dma;
if (!dbc) return; @@ -106,20 +127,8 @@ static void xhci_dbc_init_contexts(struc info->serial = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 3); info->length = cpu_to_le32(string_length);
- /* Populate bulk out endpoint context: */ - ep_ctx = dbc_bulkout_ctx(dbc); - max_burst = DBC_CTRL_MAXBURST(readl(&dbc->regs->control)); - deq = dbc_bulkout_enq(dbc); - ep_ctx->ep_info = 0; - ep_ctx->ep_info2 = dbc_epctx_info2(BULK_OUT_EP, 1024, max_burst); - ep_ctx->deq = cpu_to_le64(deq | dbc->ring_out->cycle_state); - - /* Populate bulk in endpoint context: */ - ep_ctx = dbc_bulkin_ctx(dbc); - deq = dbc_bulkin_enq(dbc); - ep_ctx->ep_info = 0; - ep_ctx->ep_info2 = dbc_epctx_info2(BULK_IN_EP, 1024, max_burst); - ep_ctx->deq = cpu_to_le64(deq | dbc->ring_in->cycle_state); + /* Populate bulk in and out endpoint contexts: */ + xhci_dbc_init_ep_contexts(dbc);
/* Set DbC context and info registers: */ lo_hi_writeq(dbc->ctx->dma, &dbc->regs->dccp); @@ -421,6 +430,23 @@ dbc_alloc_ctx(struct device *dev, gfp_t return ctx; }
+static void xhci_dbc_ring_init(struct xhci_ring *ring) +{ + struct xhci_segment *seg = ring->first_seg; + + /* clear all trbs on ring in case of old ring */ + memset(seg->trbs, 0, TRB_SEGMENT_SIZE); + + /* Only event ring does not use link TRB */ + if (ring->type != TYPE_EVENT) { + union xhci_trb *trb = &seg->trbs[TRBS_PER_SEGMENT - 1]; + + trb->link.segment_ptr = cpu_to_le64(ring->first_seg->dma); + trb->link.control = cpu_to_le32(LINK_TOGGLE | TRB_TYPE(TRB_LINK)); + } + xhci_initialize_ring_info(ring, 1); +} + static struct xhci_ring * xhci_dbc_ring_alloc(struct device *dev, enum xhci_ring_type type, gfp_t flags) { @@ -449,15 +475,10 @@ xhci_dbc_ring_alloc(struct device *dev,
seg->dma = dma;
- /* Only event ring does not use link TRB */ - if (type != TYPE_EVENT) { - union xhci_trb *trb = &seg->trbs[TRBS_PER_SEGMENT - 1]; - - trb->link.segment_ptr = cpu_to_le64(dma); - trb->link.control = cpu_to_le32(LINK_TOGGLE | TRB_TYPE(TRB_LINK)); - } INIT_LIST_HEAD(&ring->td_list); - xhci_initialize_ring_info(ring, 1); + + xhci_dbc_ring_init(ring); + return ring; dma_fail: kfree(seg);