From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.154.123]) (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 1ED704F4CFA; Mon, 28 Sep 2026 19:33:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=68.232.154.123 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790624010; cv=none; b=Emd/+PeDmGiwtyBqrqu+ErOXZFMbYfsi4dfYGR04q0BXhpBIoyN8+HBaiYg8SfgTGeauWMW0oyr0U6psocey1S0w1UbA2Bck+SPWIVz8WrNHMJQz+lwKU/XwlbgIFPBfP9jidz1tscl00ergfS41PykjkYWWimLBA4FgeY2l0ME= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790624010; c=relaxed/simple; bh=7SJDHiTNZUVrA2+aUWyf6Kg0AVhJfh5JdWvOY32Bbt0=; h=From:Date:Subject:MIME-Version:Content-Type:Message-ID:References: In-Reply-To:To:CC; b=j9XJ/EH6f+NFWinCPrM1SI/PxrAj2AXaUGA47JGtRyYeUbryaTjY3DSP3MWPD2GaXjm9DuGWKinz++2KMdmTAqM8/ub5wXUoTFcZBoa6P7nzcMY21B85O4iDgksiCNBXgCZx/U6Usl9oBB075T1eqM7tyoAVGoccbejNaNJXosc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=microchip.com; spf=pass smtp.mailfrom=microchip.com; dkim=pass (2048-bit key) header.d=microchip.com header.i=@microchip.com header.b=LdZM+kgM; arc=none smtp.client-ip=68.232.154.123 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=microchip.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=microchip.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=microchip.com header.i=@microchip.com header.b="LdZM+kgM" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1790624013; x=1822160013; h=from:date:subject:mime-version:content-transfer-encoding: message-id:references:in-reply-to:to:cc; bh=7SJDHiTNZUVrA2+aUWyf6Kg0AVhJfh5JdWvOY32Bbt0=; b=LdZM+kgM+TAa0Mzoc1U6MmKZCxpPxxIraPE5Af8cgvTMEjNJg1VBXi5V aSy1qSlT2WL5aZ956p9ZKjEh58qyz8D/TPGct96XOjSEDGnVLcrayE+lP nILjULZg/PhPXfxbDler5wk5RJ7EODMZnfd68+iTOinCQm7AXr0n5JaZp wuetLa/NQNNVZOz7UQSl9fwV8o9DdTvJ5p/TD6IT85KPNOruCReJajLkW VJZ+2TiNc37hgsA/d2K6n4uwgk35mykiHHWw1ps0D1DBeu/MkmYV9kruS 6ya2yY6+mvlRSAs8FEBqR61dGLrqC6+YPrGJv355PNOdYgxYwNYNYJ20Y g==; X-CSE-ConnectionGUID: 8NjlMsaMSaehVAXQzfzFZA== X-CSE-MsgGUID: bpaGKmVvSGmO149tR8+sWQ== X-IronPort-AV: E=Sophos;i="6.27,129,1787036400"; d="scan'208";a="63340446" X-Amp-Result: SKIPPED(no attachment in message) Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa4.microchip.iphmx.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 28 Sep 2026 12:33:32 -0700 Received: from chn-vm-ex02.mchp-main.com (10.10.87.72) by chn-vm-ex02.mchp-main.com (10.10.87.72) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.58; Mon, 28 Sep 2026 12:33:26 -0700 Received: from DEN-DL-M70577.microsemi.net (10.10.85.11) by chn-vm-ex02.mchp-main.com (10.10.85.144) with Microsoft SMTP Server id 15.1.2507.58 via Frontend Transport; Mon, 28 Sep 2026 12:33:22 -0700 From: Daniel Machon Date: Mon, 28 Sep 2026 21:32:55 +0200 Subject: [PATCH net-next v9 07/15] net: lan966x: use a dedicated device for DMA operations Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-ID: <20260928-lan966x-pci-fdma-v9-7-a17caf60f89a@microchip.com> References: <20260928-lan966x-pci-fdma-v9-0-a17caf60f89a@microchip.com> In-Reply-To: <20260928-lan966x-pci-fdma-v9-0-a17caf60f89a@microchip.com> To: Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Horatiu Vultur , Steen Hegelund , , "Alexei Starovoitov" , Daniel Borkmann , "Jesper Dangaard Brouer" , John Fastabend , Stanislav Fomichev , Herve Codina , Arnd Bergmann , Greg Kroah-Hartman , Mohsin Bashir , "Simon Horman" CC: Richard Cochran , , , , X-Mailer: b4 0.14.3 In preparation for the PCIe FDMA implementation, add lan966x->dma_dev, resolved once at probe time, and use it for every DMA operation the FDMA path performs: coherent allocations, streaming mappings and the RX page pool. Natively, dma_dev is lan966x->dev, so there is no functional change. Since dma_dev differs from dev only on the PCIe path, add lan966x_is_pci() on top of it, for the later PCIe patches to key off. Signed-off-by: Daniel Machon Reviewed-by: Simon Horman --- .../net/ethernet/microchip/lan966x/lan966x_fdma.c | 30 +++++++++++----------- .../net/ethernet/microchip/lan966x/lan966x_main.c | 16 ++++++++++++ .../net/ethernet/microchip/lan966x/lan966x_main.h | 10 ++++++++ 3 files changed, 41 insertions(+), 15 deletions(-) diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c index 651ea03eede7..ae6e5aec5e13 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c @@ -80,7 +80,7 @@ static int lan966x_fdma_rx_alloc_page_pool(struct lan966x_rx *rx) .flags = PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV, .pool_size = rx->fdma.n_dcbs, .nid = NUMA_NO_NODE, - .dev = lan966x->dev, + .dev = lan966x->dma_dev, .dma_dir = DMA_FROM_DEVICE, .offset = XDP_PACKET_HEADROOM, .max_len = rx->max_mtu - @@ -126,7 +126,7 @@ static int lan966x_fdma_rx_alloc(struct lan966x_rx *rx) if (err) return err; - err = fdma_alloc_coherent(lan966x->dev, fdma); + err = fdma_alloc_coherent(lan966x->dma_dev, fdma); if (err) { page_pool_destroy(rx->page_pool); return err; @@ -210,7 +210,7 @@ static int lan966x_fdma_tx_alloc(struct lan966x_tx *tx) if (!tx->dcbs_buf) return -ENOMEM; - err = fdma_alloc_coherent(lan966x->dev, fdma); + err = fdma_alloc_coherent(lan966x->dma_dev, fdma); if (err) goto out; @@ -230,7 +230,7 @@ static void lan966x_fdma_tx_free(struct lan966x_tx *tx) struct lan966x *lan966x = tx->lan966x; kfree(tx->dcbs_buf); - fdma_free_coherent(lan966x->dev, &tx->fdma); + fdma_free_coherent(lan966x->dma_dev, &tx->fdma); } static void lan966x_fdma_tx_activate(struct lan966x_tx *tx) @@ -355,7 +355,7 @@ static void lan966x_fdma_tx_clear_buf(struct lan966x *lan966x, int weight) dcb_buf->used = false; if (dcb_buf->use_skb) { - dma_unmap_single(lan966x->dev, + dma_unmap_single(lan966x->dma_dev, dcb_buf->dma_addr, dcb_buf->len, DMA_TO_DEVICE); @@ -364,7 +364,7 @@ static void lan966x_fdma_tx_clear_buf(struct lan966x *lan966x, int weight) napi_consume_skb(dcb_buf->data.skb, weight); } else { if (dcb_buf->xdp_ndo) - dma_unmap_single(lan966x->dev, + dma_unmap_single(lan966x->dma_dev, dcb_buf->dma_addr, dcb_buf->len, DMA_TO_DEVICE); @@ -400,7 +400,7 @@ static int lan966x_fdma_rx_check_frame(struct lan966x_rx *rx, u64 *src_port) if (unlikely(!page)) return FDMA_ERROR; - dma_sync_single_for_cpu(lan966x->dev, + dma_sync_single_for_cpu(lan966x->dma_dev, (dma_addr_t)fdma_db_dataptr_get(db) + XDP_PACKET_HEADROOM, fdma_db_len_get(db), @@ -636,11 +636,11 @@ int lan966x_fdma_xmit_xdpf(struct lan966x_port *port, void *ptr, u32 len) lan966x_ifh_set_bypass(ifh, 1); lan966x_ifh_set_port(ifh, BIT_ULL(port->chip_port)); - dma_addr = dma_map_single(lan966x->dev, + dma_addr = dma_map_single(lan966x->dma_dev, xdpf->data - IFH_LEN_BYTES, xdpf->len + IFH_LEN_BYTES, DMA_TO_DEVICE); - if (dma_mapping_error(lan966x->dev, dma_addr)) { + if (dma_mapping_error(lan966x->dma_dev, dma_addr)) { ret = NETDEV_TX_OK; goto out; } @@ -656,7 +656,7 @@ int lan966x_fdma_xmit_xdpf(struct lan966x_port *port, void *ptr, u32 len) lan966x_ifh_set_port(ifh, BIT_ULL(port->chip_port)); dma_addr = page_pool_get_dma_addr(page); - dma_sync_single_for_device(lan966x->dev, + dma_sync_single_for_device(lan966x->dma_dev, dma_addr + XDP_PACKET_HEADROOM, len + IFH_LEN_BYTES, DMA_TO_DEVICE); @@ -735,9 +735,9 @@ int lan966x_fdma_xmit(struct sk_buff *skb, __be32 *ifh, struct net_device *dev) memcpy(skb->data, ifh, IFH_LEN_BYTES); skb_put(skb, 4); - dma_addr = dma_map_single(lan966x->dev, skb->data, skb->len, + dma_addr = dma_map_single(lan966x->dma_dev, skb->data, skb->len, DMA_TO_DEVICE); - if (dma_mapping_error(lan966x->dev, dma_addr)) { + if (dma_mapping_error(lan966x->dma_dev, dma_addr)) { dev->stats.tx_dropped++; err = NETDEV_TX_OK; goto release; @@ -843,7 +843,7 @@ static int lan966x_fdma_reload(struct lan966x *lan966x, int new_mtu) page_pool_put_full_page(page_pool, old_pages[i][j], false); - fdma_free_coherent(lan966x->dev, &fdma_rx_old); + fdma_free_coherent(lan966x->dma_dev, &fdma_rx_old); page_pool_destroy(page_pool); @@ -993,7 +993,7 @@ int lan966x_fdma_init(struct lan966x *lan966x) err = lan966x_fdma_tx_alloc(&lan966x->tx); if (err) { - fdma_free_coherent(lan966x->dev, &lan966x->rx.fdma); + fdma_free_coherent(lan966x->dma_dev, &lan966x->rx.fdma); page_pool_destroy(lan966x->rx.page_pool); return err; } @@ -1015,7 +1015,7 @@ void lan966x_fdma_deinit(struct lan966x *lan966x) napi_disable(&lan966x->napi); lan966x_fdma_rx_free_pages(&lan966x->rx); - fdma_free_coherent(lan966x->dev, &lan966x->rx.fdma); + fdma_free_coherent(lan966x->dma_dev, &lan966x->rx.fdma); page_pool_destroy(lan966x->rx.page_pool); lan966x_fdma_tx_free(&lan966x->tx); } diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c index 1179a6e127c5..2741f7c9fa4c 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c @@ -7,6 +7,7 @@ #include #include #include +#include #include #include #include @@ -1081,6 +1082,20 @@ static int lan966x_reset_switch(struct lan966x *lan966x) return 0; } +/* When enumerated over PCIe, dev is a platform device with no + * iommus/dma-ranges of its own, so DMA must target the PCIe endpoint instead. + * The result differs from dev only in that case; lan966x_is_pci() relies on it. + */ +static struct device *lan966x_get_dma_dev(struct device *dev) +{ + for (struct device *p = dev->parent; p; p = p->parent) { + if (dev_is_pci(p)) + return p; + } + + return dev; +} + static int lan966x_probe(struct platform_device *pdev) { struct fwnode_handle *ports, *portnp; @@ -1094,6 +1109,7 @@ static int lan966x_probe(struct platform_device *pdev) platform_set_drvdata(pdev, lan966x); lan966x->dev = &pdev->dev; + lan966x->dma_dev = lan966x_get_dma_dev(lan966x->dev); if (!device_get_mac_address(&pdev->dev, mac_addr)) { ether_addr_copy(lan966x->base_mac, mac_addr); diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h index 83c361abb789..3f09f8ddf620 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h @@ -270,6 +270,9 @@ struct lan966x_skb_cb { struct lan966x { struct device *dev; + /* Device used for DMA; the PCIe endpoint when enumerated over PCIe. */ + struct device *dma_dev; + u8 num_phys_ports; struct lan966x_port **ports; @@ -573,6 +576,13 @@ void lan966x_fdma_wakeup_netdev(struct lan966x *lan966x); int lan966x_fdma_get_max_frame(struct lan966x *lan966x); int lan966x_qsys_sw_status(struct lan966x *lan966x); +/* dma_dev differs from dev only on the PCIe path. */ +static inline bool lan966x_is_pci(struct lan966x *lan966x) +{ + return IS_ENABLED(CONFIG_MCHP_LAN966X_PCI) && + lan966x->dma_dev != lan966x->dev; +} + int lan966x_lag_port_join(struct lan966x_port *port, struct net_device *brport_dev, struct net_device *bond, -- 2.34.1