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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/dma/sh/usb-dmac.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to '')
-rw-r--r--drivers/dma/sh/usb-dmac.c914
1 files changed, 914 insertions, 0 deletions
diff --git a/drivers/dma/sh/usb-dmac.c b/drivers/dma/sh/usb-dmac.c
new file mode 100644
index 000000000..5edaeb89d
--- /dev/null
+++ b/drivers/dma/sh/usb-dmac.c
@@ -0,0 +1,914 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Renesas USB DMA Controller Driver
+ *
+ * Copyright (C) 2015 Renesas Electronics Corporation
+ *
+ * based on rcar-dmac.c
+ * Copyright (C) 2014 Renesas Electronics Inc.
+ * Author: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_dma.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include "../dmaengine.h"
+#include "../virt-dma.h"
+
+/*
+ * struct usb_dmac_sg - Descriptor for a hardware transfer
+ * @mem_addr: memory address
+ * @size: transfer size in bytes
+ */
+struct usb_dmac_sg {
+ dma_addr_t mem_addr;
+ u32 size;
+};
+
+/*
+ * struct usb_dmac_desc - USB DMA Transfer Descriptor
+ * @vd: base virtual channel DMA transaction descriptor
+ * @direction: direction of the DMA transfer
+ * @sg_allocated_len: length of allocated sg
+ * @sg_len: length of sg
+ * @sg_index: index of sg
+ * @residue: residue after the DMAC completed a transfer
+ * @node: node for desc_got and desc_freed
+ * @done_cookie: cookie after the DMAC completed a transfer
+ * @sg: information for the transfer
+ */
+struct usb_dmac_desc {
+ struct virt_dma_desc vd;
+ enum dma_transfer_direction direction;
+ unsigned int sg_allocated_len;
+ unsigned int sg_len;
+ unsigned int sg_index;
+ u32 residue;
+ struct list_head node;
+ dma_cookie_t done_cookie;
+ struct usb_dmac_sg sg[];
+};
+
+#define to_usb_dmac_desc(vd) container_of(vd, struct usb_dmac_desc, vd)
+
+/*
+ * struct usb_dmac_chan - USB DMA Controller Channel
+ * @vc: base virtual DMA channel object
+ * @iomem: channel I/O memory base
+ * @index: index of this channel in the controller
+ * @irq: irq number of this channel
+ * @desc: the current descriptor
+ * @descs_allocated: number of descriptors allocated
+ * @desc_got: got descriptors
+ * @desc_freed: freed descriptors after the DMAC completed a transfer
+ */
+struct usb_dmac_chan {
+ struct virt_dma_chan vc;
+ void __iomem *iomem;
+ unsigned int index;
+ int irq;
+ struct usb_dmac_desc *desc;
+ int descs_allocated;
+ struct list_head desc_got;
+ struct list_head desc_freed;
+};
+
+#define to_usb_dmac_chan(c) container_of(c, struct usb_dmac_chan, vc.chan)
+
+/*
+ * struct usb_dmac - USB DMA Controller
+ * @engine: base DMA engine object
+ * @dev: the hardware device
+ * @iomem: remapped I/O memory base
+ * @n_channels: number of available channels
+ * @channels: array of DMAC channels
+ */
+struct usb_dmac {
+ struct dma_device engine;
+ struct device *dev;
+ void __iomem *iomem;
+
+ unsigned int n_channels;
+ struct usb_dmac_chan *channels;
+};
+
+#define to_usb_dmac(d) container_of(d, struct usb_dmac, engine)
+
+/* -----------------------------------------------------------------------------
+ * Registers
+ */
+
+#define USB_DMAC_CHAN_OFFSET(i) (0x20 + 0x20 * (i))
+
+#define USB_DMASWR 0x0008
+#define USB_DMASWR_SWR (1 << 0)
+#define USB_DMAOR 0x0060
+#define USB_DMAOR_AE (1 << 1)
+#define USB_DMAOR_DME (1 << 0)
+
+#define USB_DMASAR 0x0000
+#define USB_DMADAR 0x0004
+#define USB_DMATCR 0x0008
+#define USB_DMATCR_MASK 0x00ffffff
+#define USB_DMACHCR 0x0014
+#define USB_DMACHCR_FTE (1 << 24)
+#define USB_DMACHCR_NULLE (1 << 16)
+#define USB_DMACHCR_NULL (1 << 12)
+#define USB_DMACHCR_TS_8B ((0 << 7) | (0 << 6))
+#define USB_DMACHCR_TS_16B ((0 << 7) | (1 << 6))
+#define USB_DMACHCR_TS_32B ((1 << 7) | (0 << 6))
+#define USB_DMACHCR_IE (1 << 5)
+#define USB_DMACHCR_SP (1 << 2)
+#define USB_DMACHCR_TE (1 << 1)
+#define USB_DMACHCR_DE (1 << 0)
+#define USB_DMATEND 0x0018
+
+/* Hardcode the xfer_shift to 5 (32bytes) */
+#define USB_DMAC_XFER_SHIFT 5
+#define USB_DMAC_XFER_SIZE (1 << USB_DMAC_XFER_SHIFT)
+#define USB_DMAC_CHCR_TS USB_DMACHCR_TS_32B
+#define USB_DMAC_SLAVE_BUSWIDTH DMA_SLAVE_BUSWIDTH_32_BYTES
+
+/* for descriptors */
+#define USB_DMAC_INITIAL_NR_DESC 16
+#define USB_DMAC_INITIAL_NR_SG 8
+
+/* -----------------------------------------------------------------------------
+ * Device access
+ */
+
+static void usb_dmac_write(struct usb_dmac *dmac, u32 reg, u32 data)
+{
+ writel(data, dmac->iomem + reg);
+}
+
+static u32 usb_dmac_read(struct usb_dmac *dmac, u32 reg)
+{
+ return readl(dmac->iomem + reg);
+}
+
+static u32 usb_dmac_chan_read(struct usb_dmac_chan *chan, u32 reg)
+{
+ return readl(chan->iomem + reg);
+}
+
+static void usb_dmac_chan_write(struct usb_dmac_chan *chan, u32 reg, u32 data)
+{
+ writel(data, chan->iomem + reg);
+}
+
+/* -----------------------------------------------------------------------------
+ * Initialization and configuration
+ */
+
+static bool usb_dmac_chan_is_busy(struct usb_dmac_chan *chan)
+{
+ u32 chcr = usb_dmac_chan_read(chan, USB_DMACHCR);
+
+ return (chcr & (USB_DMACHCR_DE | USB_DMACHCR_TE)) == USB_DMACHCR_DE;
+}
+
+static u32 usb_dmac_calc_tend(u32 size)
+{
+ /*
+ * Please refer to the Figure "Example of Final Transaction Valid
+ * Data Transfer Enable (EDTEN) Setting" in the data sheet.
+ */
+ return 0xffffffff << (32 - (size % USB_DMAC_XFER_SIZE ? :
+ USB_DMAC_XFER_SIZE));
+}
+
+/* This function is already held by vc.lock */
+static void usb_dmac_chan_start_sg(struct usb_dmac_chan *chan,
+ unsigned int index)
+{
+ struct usb_dmac_desc *desc = chan->desc;
+ struct usb_dmac_sg *sg = desc->sg + index;
+ dma_addr_t src_addr = 0, dst_addr = 0;
+
+ WARN_ON_ONCE(usb_dmac_chan_is_busy(chan));
+
+ if (desc->direction == DMA_DEV_TO_MEM)
+ dst_addr = sg->mem_addr;
+ else
+ src_addr = sg->mem_addr;
+
+ dev_dbg(chan->vc.chan.device->dev,
+ "chan%u: queue sg %p: %u@%pad -> %pad\n",
+ chan->index, sg, sg->size, &src_addr, &dst_addr);
+
+ usb_dmac_chan_write(chan, USB_DMASAR, src_addr & 0xffffffff);
+ usb_dmac_chan_write(chan, USB_DMADAR, dst_addr & 0xffffffff);
+ usb_dmac_chan_write(chan, USB_DMATCR,
+ DIV_ROUND_UP(sg->size, USB_DMAC_XFER_SIZE));
+ usb_dmac_chan_write(chan, USB_DMATEND, usb_dmac_calc_tend(sg->size));
+
+ usb_dmac_chan_write(chan, USB_DMACHCR, USB_DMAC_CHCR_TS |
+ USB_DMACHCR_NULLE | USB_DMACHCR_IE | USB_DMACHCR_DE);
+}
+
+/* This function is already held by vc.lock */
+static void usb_dmac_chan_start_desc(struct usb_dmac_chan *chan)
+{
+ struct virt_dma_desc *vd;
+
+ vd = vchan_next_desc(&chan->vc);
+ if (!vd) {
+ chan->desc = NULL;
+ return;
+ }
+
+ /*
+ * Remove this request from vc->desc_issued. Otherwise, this driver
+ * will get the previous value from vchan_next_desc() after a transfer
+ * was completed.
+ */
+ list_del(&vd->node);
+
+ chan->desc = to_usb_dmac_desc(vd);
+ chan->desc->sg_index = 0;
+ usb_dmac_chan_start_sg(chan, 0);
+}
+
+static int usb_dmac_init(struct usb_dmac *dmac)
+{
+ u16 dmaor;
+
+ /* Clear all channels and enable the DMAC globally. */
+ usb_dmac_write(dmac, USB_DMAOR, USB_DMAOR_DME);
+
+ dmaor = usb_dmac_read(dmac, USB_DMAOR);
+ if ((dmaor & (USB_DMAOR_AE | USB_DMAOR_DME)) != USB_DMAOR_DME) {
+ dev_warn(dmac->dev, "DMAOR initialization failed.\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+/* -----------------------------------------------------------------------------
+ * Descriptors allocation and free
+ */
+static int usb_dmac_desc_alloc(struct usb_dmac_chan *chan, unsigned int sg_len,
+ gfp_t gfp)
+{
+ struct usb_dmac_desc *desc;
+ unsigned long flags;
+
+ desc = kzalloc(struct_size(desc, sg, sg_len), gfp);
+ if (!desc)
+ return -ENOMEM;
+
+ desc->sg_allocated_len = sg_len;
+ INIT_LIST_HEAD(&desc->node);
+
+ spin_lock_irqsave(&chan->vc.lock, flags);
+ list_add_tail(&desc->node, &chan->desc_freed);
+ spin_unlock_irqrestore(&chan->vc.lock, flags);
+
+ return 0;
+}
+
+static void usb_dmac_desc_free(struct usb_dmac_chan *chan)
+{
+ struct usb_dmac_desc *desc, *_desc;
+ LIST_HEAD(list);
+
+ list_splice_init(&chan->desc_freed, &list);
+ list_splice_init(&chan->desc_got, &list);
+
+ list_for_each_entry_safe(desc, _desc, &list, node) {
+ list_del(&desc->node);
+ kfree(desc);
+ }
+ chan->descs_allocated = 0;
+}
+
+static struct usb_dmac_desc *usb_dmac_desc_get(struct usb_dmac_chan *chan,
+ unsigned int sg_len, gfp_t gfp)
+{
+ struct usb_dmac_desc *desc = NULL;
+ unsigned long flags;
+
+ /* Get a freed descritpor */
+ spin_lock_irqsave(&chan->vc.lock, flags);
+ list_for_each_entry(desc, &chan->desc_freed, node) {
+ if (sg_len <= desc->sg_allocated_len) {
+ list_move_tail(&desc->node, &chan->desc_got);
+ spin_unlock_irqrestore(&chan->vc.lock, flags);
+ return desc;
+ }
+ }
+ spin_unlock_irqrestore(&chan->vc.lock, flags);
+
+ /* Allocate a new descriptor */
+ if (!usb_dmac_desc_alloc(chan, sg_len, gfp)) {
+ /* If allocated the desc, it was added to tail of the list */
+ spin_lock_irqsave(&chan->vc.lock, flags);
+ desc = list_last_entry(&chan->desc_freed, struct usb_dmac_desc,
+ node);
+ list_move_tail(&desc->node, &chan->desc_got);
+ spin_unlock_irqrestore(&chan->vc.lock, flags);
+ return desc;
+ }
+
+ return NULL;
+}
+
+static void usb_dmac_desc_put(struct usb_dmac_chan *chan,
+ struct usb_dmac_desc *desc)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&chan->vc.lock, flags);
+ list_move_tail(&desc->node, &chan->desc_freed);
+ spin_unlock_irqrestore(&chan->vc.lock, flags);
+}
+
+/* -----------------------------------------------------------------------------
+ * Stop and reset
+ */
+
+static void usb_dmac_soft_reset(struct usb_dmac_chan *uchan)
+{
+ struct dma_chan *chan = &uchan->vc.chan;
+ struct usb_dmac *dmac = to_usb_dmac(chan->device);
+ int i;
+
+ /* Don't issue soft reset if any one of channels is busy */
+ for (i = 0; i < dmac->n_channels; ++i) {
+ if (usb_dmac_chan_is_busy(uchan))
+ return;
+ }
+
+ usb_dmac_write(dmac, USB_DMAOR, 0);
+ usb_dmac_write(dmac, USB_DMASWR, USB_DMASWR_SWR);
+ udelay(100);
+ usb_dmac_write(dmac, USB_DMASWR, 0);
+ usb_dmac_write(dmac, USB_DMAOR, 1);
+}
+
+static void usb_dmac_chan_halt(struct usb_dmac_chan *chan)
+{
+ u32 chcr = usb_dmac_chan_read(chan, USB_DMACHCR);
+
+ chcr &= ~(USB_DMACHCR_IE | USB_DMACHCR_TE | USB_DMACHCR_DE);
+ usb_dmac_chan_write(chan, USB_DMACHCR, chcr);
+
+ usb_dmac_soft_reset(chan);
+}
+
+static void usb_dmac_stop(struct usb_dmac *dmac)
+{
+ usb_dmac_write(dmac, USB_DMAOR, 0);
+}
+
+/* -----------------------------------------------------------------------------
+ * DMA engine operations
+ */
+
+static int usb_dmac_alloc_chan_resources(struct dma_chan *chan)
+{
+ struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan);
+ int ret;
+
+ while (uchan->descs_allocated < USB_DMAC_INITIAL_NR_DESC) {
+ ret = usb_dmac_desc_alloc(uchan, USB_DMAC_INITIAL_NR_SG,
+ GFP_KERNEL);
+ if (ret < 0) {
+ usb_dmac_desc_free(uchan);
+ return ret;
+ }
+ uchan->descs_allocated++;
+ }
+
+ return pm_runtime_get_sync(chan->device->dev);
+}
+
+static void usb_dmac_free_chan_resources(struct dma_chan *chan)
+{
+ struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan);
+ unsigned long flags;
+
+ /* Protect against ISR */
+ spin_lock_irqsave(&uchan->vc.lock, flags);
+ usb_dmac_chan_halt(uchan);
+ spin_unlock_irqrestore(&uchan->vc.lock, flags);
+
+ usb_dmac_desc_free(uchan);
+ vchan_free_chan_resources(&uchan->vc);
+
+ pm_runtime_put(chan->device->dev);
+}
+
+static struct dma_async_tx_descriptor *
+usb_dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
+ unsigned int sg_len, enum dma_transfer_direction dir,
+ unsigned long dma_flags, void *context)
+{
+ struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan);
+ struct usb_dmac_desc *desc;
+ struct scatterlist *sg;
+ int i;
+
+ if (!sg_len) {
+ dev_warn(chan->device->dev,
+ "%s: bad parameter: len=%d\n", __func__, sg_len);
+ return NULL;
+ }
+
+ desc = usb_dmac_desc_get(uchan, sg_len, GFP_NOWAIT);
+ if (!desc)
+ return NULL;
+
+ desc->direction = dir;
+ desc->sg_len = sg_len;
+ for_each_sg(sgl, sg, sg_len, i) {
+ desc->sg[i].mem_addr = sg_dma_address(sg);
+ desc->sg[i].size = sg_dma_len(sg);
+ }
+
+ return vchan_tx_prep(&uchan->vc, &desc->vd, dma_flags);
+}
+
+static int usb_dmac_chan_terminate_all(struct dma_chan *chan)
+{
+ struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan);
+ struct usb_dmac_desc *desc, *_desc;
+ unsigned long flags;
+ LIST_HEAD(head);
+ LIST_HEAD(list);
+
+ spin_lock_irqsave(&uchan->vc.lock, flags);
+ usb_dmac_chan_halt(uchan);
+ vchan_get_all_descriptors(&uchan->vc, &head);
+ if (uchan->desc)
+ uchan->desc = NULL;
+ list_splice_init(&uchan->desc_got, &list);
+ list_for_each_entry_safe(desc, _desc, &list, node)
+ list_move_tail(&desc->node, &uchan->desc_freed);
+ spin_unlock_irqrestore(&uchan->vc.lock, flags);
+ vchan_dma_desc_free_list(&uchan->vc, &head);
+
+ return 0;
+}
+
+static unsigned int usb_dmac_get_current_residue(struct usb_dmac_chan *chan,
+ struct usb_dmac_desc *desc,
+ unsigned int sg_index)
+{
+ struct usb_dmac_sg *sg = desc->sg + sg_index;
+ u32 mem_addr = sg->mem_addr & 0xffffffff;
+ unsigned int residue = sg->size;
+
+ /*
+ * We cannot use USB_DMATCR to calculate residue because USB_DMATCR
+ * has unsuited value to calculate.
+ */
+ if (desc->direction == DMA_DEV_TO_MEM)
+ residue -= usb_dmac_chan_read(chan, USB_DMADAR) - mem_addr;
+ else
+ residue -= usb_dmac_chan_read(chan, USB_DMASAR) - mem_addr;
+
+ return residue;
+}
+
+static u32 usb_dmac_chan_get_residue_if_complete(struct usb_dmac_chan *chan,
+ dma_cookie_t cookie)
+{
+ struct usb_dmac_desc *desc;
+ u32 residue = 0;
+
+ list_for_each_entry_reverse(desc, &chan->desc_freed, node) {
+ if (desc->done_cookie == cookie) {
+ residue = desc->residue;
+ break;
+ }
+ }
+
+ return residue;
+}
+
+static u32 usb_dmac_chan_get_residue(struct usb_dmac_chan *chan,
+ dma_cookie_t cookie)
+{
+ u32 residue = 0;
+ struct virt_dma_desc *vd;
+ struct usb_dmac_desc *desc = chan->desc;
+ int i;
+
+ if (!desc) {
+ vd = vchan_find_desc(&chan->vc, cookie);
+ if (!vd)
+ return 0;
+ desc = to_usb_dmac_desc(vd);
+ }
+
+ /* Compute the size of all usb_dmac_sg still to be transferred */
+ for (i = desc->sg_index + 1; i < desc->sg_len; i++)
+ residue += desc->sg[i].size;
+
+ /* Add the residue for the current sg */
+ residue += usb_dmac_get_current_residue(chan, desc, desc->sg_index);
+
+ return residue;
+}
+
+static enum dma_status usb_dmac_tx_status(struct dma_chan *chan,
+ dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan);
+ enum dma_status status;
+ unsigned int residue = 0;
+ unsigned long flags;
+
+ status = dma_cookie_status(chan, cookie, txstate);
+ /* a client driver will get residue after DMA_COMPLETE */
+ if (!txstate)
+ return status;
+
+ spin_lock_irqsave(&uchan->vc.lock, flags);
+ if (status == DMA_COMPLETE)
+ residue = usb_dmac_chan_get_residue_if_complete(uchan, cookie);
+ else
+ residue = usb_dmac_chan_get_residue(uchan, cookie);
+ spin_unlock_irqrestore(&uchan->vc.lock, flags);
+
+ dma_set_residue(txstate, residue);
+
+ return status;
+}
+
+static void usb_dmac_issue_pending(struct dma_chan *chan)
+{
+ struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&uchan->vc.lock, flags);
+ if (vchan_issue_pending(&uchan->vc) && !uchan->desc)
+ usb_dmac_chan_start_desc(uchan);
+ spin_unlock_irqrestore(&uchan->vc.lock, flags);
+}
+
+static void usb_dmac_virt_desc_free(struct virt_dma_desc *vd)
+{
+ struct usb_dmac_desc *desc = to_usb_dmac_desc(vd);
+ struct usb_dmac_chan *chan = to_usb_dmac_chan(vd->tx.chan);
+
+ usb_dmac_desc_put(chan, desc);
+}
+
+/* -----------------------------------------------------------------------------
+ * IRQ handling
+ */
+
+static void usb_dmac_isr_transfer_end(struct usb_dmac_chan *chan)
+{
+ struct usb_dmac_desc *desc = chan->desc;
+
+ BUG_ON(!desc);
+
+ if (++desc->sg_index < desc->sg_len) {
+ usb_dmac_chan_start_sg(chan, desc->sg_index);
+ } else {
+ desc->residue = usb_dmac_get_current_residue(chan, desc,
+ desc->sg_index - 1);
+ desc->done_cookie = desc->vd.tx.cookie;
+ desc->vd.tx_result.result = DMA_TRANS_NOERROR;
+ desc->vd.tx_result.residue = desc->residue;
+ vchan_cookie_complete(&desc->vd);
+
+ /* Restart the next transfer if this driver has a next desc */
+ usb_dmac_chan_start_desc(chan);
+ }
+}
+
+static irqreturn_t usb_dmac_isr_channel(int irq, void *dev)
+{
+ struct usb_dmac_chan *chan = dev;
+ irqreturn_t ret = IRQ_NONE;
+ u32 mask = 0;
+ u32 chcr;
+ bool xfer_end = false;
+
+ spin_lock(&chan->vc.lock);
+
+ chcr = usb_dmac_chan_read(chan, USB_DMACHCR);
+ if (chcr & (USB_DMACHCR_TE | USB_DMACHCR_SP)) {
+ mask |= USB_DMACHCR_DE | USB_DMACHCR_TE | USB_DMACHCR_SP;
+ if (chcr & USB_DMACHCR_DE)
+ xfer_end = true;
+ ret |= IRQ_HANDLED;
+ }
+ if (chcr & USB_DMACHCR_NULL) {
+ /* An interruption of TE will happen after we set FTE */
+ mask |= USB_DMACHCR_NULL;
+ chcr |= USB_DMACHCR_FTE;
+ ret |= IRQ_HANDLED;
+ }
+ if (mask)
+ usb_dmac_chan_write(chan, USB_DMACHCR, chcr & ~mask);
+
+ if (xfer_end)
+ usb_dmac_isr_transfer_end(chan);
+
+ spin_unlock(&chan->vc.lock);
+
+ return ret;
+}
+
+/* -----------------------------------------------------------------------------
+ * OF xlate and channel filter
+ */
+
+static bool usb_dmac_chan_filter(struct dma_chan *chan, void *arg)
+{
+ struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan);
+ struct of_phandle_args *dma_spec = arg;
+
+ /* USB-DMAC should be used with fixed usb controller's FIFO */
+ if (uchan->index != dma_spec->args[0])
+ return false;
+
+ return true;
+}
+
+static struct dma_chan *usb_dmac_of_xlate(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma)
+{
+ struct dma_chan *chan;
+ dma_cap_mask_t mask;
+
+ if (dma_spec->args_count != 1)
+ return NULL;
+
+ /* Only slave DMA channels can be allocated via DT */
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ chan = __dma_request_channel(&mask, usb_dmac_chan_filter, dma_spec,
+ ofdma->of_node);
+ if (!chan)
+ return NULL;
+
+ return chan;
+}
+
+/* -----------------------------------------------------------------------------
+ * Power management
+ */
+
+#ifdef CONFIG_PM
+static int usb_dmac_runtime_suspend(struct device *dev)
+{
+ struct usb_dmac *dmac = dev_get_drvdata(dev);
+ int i;
+
+ for (i = 0; i < dmac->n_channels; ++i) {
+ if (!dmac->channels[i].iomem)
+ break;
+ usb_dmac_chan_halt(&dmac->channels[i]);
+ }
+
+ return 0;
+}
+
+static int usb_dmac_runtime_resume(struct device *dev)
+{
+ struct usb_dmac *dmac = dev_get_drvdata(dev);
+
+ return usb_dmac_init(dmac);
+}
+#endif /* CONFIG_PM */
+
+static const struct dev_pm_ops usb_dmac_pm = {
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_RUNTIME_PM_OPS(usb_dmac_runtime_suspend, usb_dmac_runtime_resume,
+ NULL)
+};
+
+/* -----------------------------------------------------------------------------
+ * Probe and remove
+ */
+
+static int usb_dmac_chan_probe(struct usb_dmac *dmac,
+ struct usb_dmac_chan *uchan,
+ unsigned int index)
+{
+ struct platform_device *pdev = to_platform_device(dmac->dev);
+ char pdev_irqname[5];
+ char *irqname;
+ int ret;
+
+ uchan->index = index;
+ uchan->iomem = dmac->iomem + USB_DMAC_CHAN_OFFSET(index);
+
+ /* Request the channel interrupt. */
+ sprintf(pdev_irqname, "ch%u", index);
+ uchan->irq = platform_get_irq_byname(pdev, pdev_irqname);
+ if (uchan->irq < 0)
+ return -ENODEV;
+
+ irqname = devm_kasprintf(dmac->dev, GFP_KERNEL, "%s:%u",
+ dev_name(dmac->dev), index);
+ if (!irqname)
+ return -ENOMEM;
+
+ ret = devm_request_irq(dmac->dev, uchan->irq, usb_dmac_isr_channel,
+ IRQF_SHARED, irqname, uchan);
+ if (ret) {
+ dev_err(dmac->dev, "failed to request IRQ %u (%d)\n",
+ uchan->irq, ret);
+ return ret;
+ }
+
+ uchan->vc.desc_free = usb_dmac_virt_desc_free;
+ vchan_init(&uchan->vc, &dmac->engine);
+ INIT_LIST_HEAD(&uchan->desc_freed);
+ INIT_LIST_HEAD(&uchan->desc_got);
+
+ return 0;
+}
+
+static int usb_dmac_parse_of(struct device *dev, struct usb_dmac *dmac)
+{
+ struct device_node *np = dev->of_node;
+ int ret;
+
+ ret = of_property_read_u32(np, "dma-channels", &dmac->n_channels);
+ if (ret < 0) {
+ dev_err(dev, "unable to read dma-channels property\n");
+ return ret;
+ }
+
+ if (dmac->n_channels <= 0 || dmac->n_channels >= 100) {
+ dev_err(dev, "invalid number of channels %u\n",
+ dmac->n_channels);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int usb_dmac_probe(struct platform_device *pdev)
+{
+ const enum dma_slave_buswidth widths = USB_DMAC_SLAVE_BUSWIDTH;
+ struct dma_device *engine;
+ struct usb_dmac *dmac;
+ struct resource *mem;
+ unsigned int i;
+ int ret;
+
+ dmac = devm_kzalloc(&pdev->dev, sizeof(*dmac), GFP_KERNEL);
+ if (!dmac)
+ return -ENOMEM;
+
+ dmac->dev = &pdev->dev;
+ platform_set_drvdata(pdev, dmac);
+
+ ret = usb_dmac_parse_of(&pdev->dev, dmac);
+ if (ret < 0)
+ return ret;
+
+ dmac->channels = devm_kcalloc(&pdev->dev, dmac->n_channels,
+ sizeof(*dmac->channels), GFP_KERNEL);
+ if (!dmac->channels)
+ return -ENOMEM;
+
+ /* Request resources. */
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ dmac->iomem = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(dmac->iomem))
+ return PTR_ERR(dmac->iomem);
+
+ /* Enable runtime PM and initialize the device. */
+ pm_runtime_enable(&pdev->dev);
+ ret = pm_runtime_get_sync(&pdev->dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "runtime PM get sync failed (%d)\n", ret);
+ goto error_pm;
+ }
+
+ ret = usb_dmac_init(dmac);
+
+ if (ret) {
+ dev_err(&pdev->dev, "failed to reset device\n");
+ goto error;
+ }
+
+ /* Initialize the channels. */
+ INIT_LIST_HEAD(&dmac->engine.channels);
+
+ for (i = 0; i < dmac->n_channels; ++i) {
+ ret = usb_dmac_chan_probe(dmac, &dmac->channels[i], i);
+ if (ret < 0)
+ goto error;
+ }
+
+ /* Register the DMAC as a DMA provider for DT. */
+ ret = of_dma_controller_register(pdev->dev.of_node, usb_dmac_of_xlate,
+ NULL);
+ if (ret < 0)
+ goto error;
+
+ /*
+ * Register the DMA engine device.
+ *
+ * Default transfer size of 32 bytes requires 32-byte alignment.
+ */
+ engine = &dmac->engine;
+ dma_cap_set(DMA_SLAVE, engine->cap_mask);
+
+ engine->dev = &pdev->dev;
+
+ engine->src_addr_widths = widths;
+ engine->dst_addr_widths = widths;
+ engine->directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
+ engine->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
+
+ engine->device_alloc_chan_resources = usb_dmac_alloc_chan_resources;
+ engine->device_free_chan_resources = usb_dmac_free_chan_resources;
+ engine->device_prep_slave_sg = usb_dmac_prep_slave_sg;
+ engine->device_terminate_all = usb_dmac_chan_terminate_all;
+ engine->device_tx_status = usb_dmac_tx_status;
+ engine->device_issue_pending = usb_dmac_issue_pending;
+
+ ret = dma_async_device_register(engine);
+ if (ret < 0)
+ goto error;
+
+ pm_runtime_put(&pdev->dev);
+ return 0;
+
+error:
+ of_dma_controller_free(pdev->dev.of_node);
+error_pm:
+ pm_runtime_put(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ return ret;
+}
+
+static void usb_dmac_chan_remove(struct usb_dmac *dmac,
+ struct usb_dmac_chan *uchan)
+{
+ usb_dmac_chan_halt(uchan);
+ devm_free_irq(dmac->dev, uchan->irq, uchan);
+}
+
+static int usb_dmac_remove(struct platform_device *pdev)
+{
+ struct usb_dmac *dmac = platform_get_drvdata(pdev);
+ int i;
+
+ for (i = 0; i < dmac->n_channels; ++i)
+ usb_dmac_chan_remove(dmac, &dmac->channels[i]);
+ of_dma_controller_free(pdev->dev.of_node);
+ dma_async_device_unregister(&dmac->engine);
+
+ pm_runtime_disable(&pdev->dev);
+
+ return 0;
+}
+
+static void usb_dmac_shutdown(struct platform_device *pdev)
+{
+ struct usb_dmac *dmac = platform_get_drvdata(pdev);
+
+ usb_dmac_stop(dmac);
+}
+
+static const struct of_device_id usb_dmac_of_ids[] = {
+ { .compatible = "renesas,usb-dmac", },
+ { /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, usb_dmac_of_ids);
+
+static struct platform_driver usb_dmac_driver = {
+ .driver = {
+ .pm = &usb_dmac_pm,
+ .name = "usb-dmac",
+ .of_match_table = usb_dmac_of_ids,
+ },
+ .probe = usb_dmac_probe,
+ .remove = usb_dmac_remove,
+ .shutdown = usb_dmac_shutdown,
+};
+
+module_platform_driver(usb_dmac_driver);
+
+MODULE_DESCRIPTION("Renesas USB DMA Controller Driver");
+MODULE_AUTHOR("Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>");
+MODULE_LICENSE("GPL v2");