From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B6D122D375C for ; Wed, 17 Sep 2025 14:04:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758117874; cv=none; b=lBJnNl77Sv7NaN6kQwS8p6bQp3OmyZy0fJV26ACqN2SICgt71w3RWk+syOVuVGg0aCufzGSw5KDkc/5xYqehVjxKmpPj3xezPFkNGwx353ISM4mwDmC6DETpGs0s19yOmug1IwKTFwpcA3RaNOrTD0LddKmV3fgmyW0MJNmTF4s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758117874; c=relaxed/simple; bh=FRjqmATT49PWql4p1qiU7GCHYVIDlOcTa/XEhe7sU8U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cbuPcR0R2P0zFpWoE2trP3qrMK8GeCVoo7GqyhiT0AsMw2P2unT/Tlhb08DoISFI7tHdnazuRQaKnNWfv7ptds+GjhfCN8wvQOCFZsQozgU4Nu8wuqIYTH1MhzwJlxwuXfmCD1uEy6Q5C8IbB8a15/S89gmFW5hbAvVmG+dJJUI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tSuxir0J; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="tSuxir0J" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BAB8EC4CEE7; Wed, 17 Sep 2025 14:04:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1758117874; bh=FRjqmATT49PWql4p1qiU7GCHYVIDlOcTa/XEhe7sU8U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tSuxir0J1fOwrr0q+L+CgQ4XjocJVqgu7/K+JN98pL5AQZE3yKmnG6Ogr6K/A59aw cNniu2opEzpv1ZSK/dOZh2zpm7MZHSq/omeby57HOcCesHoHj5AkGxUqAa7GIpl14P OnEEpmfgPz6NVdflnimad+BPyihCNgvW46UzmZ7yidRDYthPSVOqF3tfyZ1uUExNyH un4NWs1qo0PcnDwXtmNQPop6+6ggu4Z2cwGHk3lXEsKzr7h9KwmYF1ShigGfI1Vc02 oJOpLo5dvM8lchcknucfREW5Wd0XfMs2lrxgOQC/foqO1KLjZM/nUBP8CDA/yT166V VnqFEmcuwZKNg== From: Sasha Levin To: stable@vger.kernel.org Cc: Mathias Nyman , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH 5.15.y 1/2] xhci: dbc: decouple endpoint allocation from initialization Date: Wed, 17 Sep 2025 10:04:31 -0400 Message-ID: <20250917140432.571445-1-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <2025091747-thirstily-dispose-3727@gregkh> References: <2025091747-thirstily-dispose-3727@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Mathias Nyman [ 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 Link: https://lore.kernel.org/r/20250902105306.877476-2-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/host/xhci-dbgcap.c | 71 ++++++++++++++++++++++------------ 1 file changed, 46 insertions(+), 25 deletions(-) diff --git a/drivers/usb/host/xhci-dbgcap.c b/drivers/usb/host/xhci-dbgcap.c index 1091f6fd14c9f..e0956042a465c 100644 --- a/drivers/usb/host/xhci-dbgcap.c +++ b/drivers/usb/host/xhci-dbgcap.c @@ -86,13 +86,34 @@ static u32 xhci_dbc_populate_strings(struct dbc_str_descs *strings) 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(struct xhci_dbc *dbc, u32 string_length) 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 flags) 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, enum xhci_ring_type type, gfp_t flags) 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); -- 2.51.0