From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- drivers/media/pci/saa7164/saa7164-bus.c | 467 ++++++++++++++++++++++++++++++++ 1 file changed, 467 insertions(+) create mode 100644 drivers/media/pci/saa7164/saa7164-bus.c (limited to 'drivers/media/pci/saa7164/saa7164-bus.c') diff --git a/drivers/media/pci/saa7164/saa7164-bus.c b/drivers/media/pci/saa7164/saa7164-bus.c new file mode 100644 index 000000000..16739895a --- /dev/null +++ b/drivers/media/pci/saa7164/saa7164-bus.c @@ -0,0 +1,467 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for the NXP SAA7164 PCIe bridge + * + * Copyright (c) 2010-2015 Steven Toth + */ + +#include "saa7164.h" + +/* The message bus to/from the firmware is a ring buffer in PCI address + * space. Establish the defaults. + */ +int saa7164_bus_setup(struct saa7164_dev *dev) +{ + struct tmComResBusInfo *b = &dev->bus; + + mutex_init(&b->lock); + + b->Type = TYPE_BUS_PCIe; + b->m_wMaxReqSize = SAA_DEVICE_MAXREQUESTSIZE; + + b->m_pdwSetRing = (u8 __iomem *)(dev->bmmio + + ((u32)dev->busdesc.CommandRing)); + + b->m_dwSizeSetRing = SAA_DEVICE_BUFFERBLOCKSIZE; + + b->m_pdwGetRing = (u8 __iomem *)(dev->bmmio + + ((u32)dev->busdesc.ResponseRing)); + + b->m_dwSizeGetRing = SAA_DEVICE_BUFFERBLOCKSIZE; + + b->m_dwSetWritePos = ((u32)dev->intfdesc.BARLocation) + + (2 * sizeof(u64)); + b->m_dwSetReadPos = b->m_dwSetWritePos + (1 * sizeof(u32)); + + b->m_dwGetWritePos = b->m_dwSetWritePos + (2 * sizeof(u32)); + b->m_dwGetReadPos = b->m_dwSetWritePos + (3 * sizeof(u32)); + + return 0; +} + +void saa7164_bus_dump(struct saa7164_dev *dev) +{ + struct tmComResBusInfo *b = &dev->bus; + + dprintk(DBGLVL_BUS, "Dumping the bus structure:\n"); + dprintk(DBGLVL_BUS, " .type = %d\n", b->Type); + dprintk(DBGLVL_BUS, " .dev->bmmio = 0x%p\n", dev->bmmio); + dprintk(DBGLVL_BUS, " .m_wMaxReqSize = 0x%x\n", b->m_wMaxReqSize); + dprintk(DBGLVL_BUS, " .m_pdwSetRing = 0x%p\n", b->m_pdwSetRing); + dprintk(DBGLVL_BUS, " .m_dwSizeSetRing = 0x%x\n", b->m_dwSizeSetRing); + dprintk(DBGLVL_BUS, " .m_pdwGetRing = 0x%p\n", b->m_pdwGetRing); + dprintk(DBGLVL_BUS, " .m_dwSizeGetRing = 0x%x\n", b->m_dwSizeGetRing); + + dprintk(DBGLVL_BUS, " .m_dwSetReadPos = 0x%x (0x%08x)\n", + b->m_dwSetReadPos, saa7164_readl(b->m_dwSetReadPos)); + + dprintk(DBGLVL_BUS, " .m_dwSetWritePos = 0x%x (0x%08x)\n", + b->m_dwSetWritePos, saa7164_readl(b->m_dwSetWritePos)); + + dprintk(DBGLVL_BUS, " .m_dwGetReadPos = 0x%x (0x%08x)\n", + b->m_dwGetReadPos, saa7164_readl(b->m_dwGetReadPos)); + + dprintk(DBGLVL_BUS, " .m_dwGetWritePos = 0x%x (0x%08x)\n", + b->m_dwGetWritePos, saa7164_readl(b->m_dwGetWritePos)); + +} + +/* Intensionally throw a BUG() if the state of the message bus looks corrupt */ +static void saa7164_bus_verify(struct saa7164_dev *dev) +{ + struct tmComResBusInfo *b = &dev->bus; + int bug = 0; + + if (saa7164_readl(b->m_dwSetReadPos) > b->m_dwSizeSetRing) + bug++; + + if (saa7164_readl(b->m_dwSetWritePos) > b->m_dwSizeSetRing) + bug++; + + if (saa7164_readl(b->m_dwGetReadPos) > b->m_dwSizeGetRing) + bug++; + + if (saa7164_readl(b->m_dwGetWritePos) > b->m_dwSizeGetRing) + bug++; + + if (bug) { + saa_debug = 0xffff; /* Ensure we get the bus dump */ + saa7164_bus_dump(dev); + saa_debug = 1024; /* Ensure we get the bus dump */ + BUG(); + } +} + +static void saa7164_bus_dumpmsg(struct saa7164_dev *dev, struct tmComResInfo *m, + void *buf) +{ + dprintk(DBGLVL_BUS, "Dumping msg structure:\n"); + dprintk(DBGLVL_BUS, " .id = %d\n", m->id); + dprintk(DBGLVL_BUS, " .flags = 0x%x\n", m->flags); + dprintk(DBGLVL_BUS, " .size = 0x%x\n", m->size); + dprintk(DBGLVL_BUS, " .command = 0x%x\n", m->command); + dprintk(DBGLVL_BUS, " .controlselector = 0x%x\n", m->controlselector); + dprintk(DBGLVL_BUS, " .seqno = %d\n", m->seqno); + if (buf) + dprintk(DBGLVL_BUS, " .buffer (ignored)\n"); +} + +/* + * Places a command or a response on the bus. The implementation does not + * know if it is a command or a response it just places the data on the + * bus depending on the bus information given in the struct tmComResBusInfo + * structure. If the command or response does not fit into the bus ring + * buffer it will be refused. + * + * Return Value: + * SAA_OK The function executed successfully. + * < 0 One or more members are not initialized. + */ +int saa7164_bus_set(struct saa7164_dev *dev, struct tmComResInfo* msg, + void *buf) +{ + struct tmComResBusInfo *bus = &dev->bus; + u32 bytes_to_write, free_write_space, timeout, curr_srp, curr_swp; + u32 new_swp, space_rem; + int ret = SAA_ERR_BAD_PARAMETER; + u16 size; + + if (!msg) { + printk(KERN_ERR "%s() !msg\n", __func__); + return SAA_ERR_BAD_PARAMETER; + } + + dprintk(DBGLVL_BUS, "%s()\n", __func__); + + saa7164_bus_verify(dev); + + if (msg->size > dev->bus.m_wMaxReqSize) { + printk(KERN_ERR "%s() Exceeded dev->bus.m_wMaxReqSize\n", + __func__); + return SAA_ERR_BAD_PARAMETER; + } + + if ((msg->size > 0) && (buf == NULL)) { + printk(KERN_ERR "%s() Missing message buffer\n", __func__); + return SAA_ERR_BAD_PARAMETER; + } + + /* Lock the bus from any other access */ + mutex_lock(&bus->lock); + + bytes_to_write = sizeof(*msg) + msg->size; + free_write_space = 0; + timeout = SAA_BUS_TIMEOUT; + curr_srp = saa7164_readl(bus->m_dwSetReadPos); + curr_swp = saa7164_readl(bus->m_dwSetWritePos); + + /* Deal with ring wrapping issues */ + if (curr_srp > curr_swp) + /* Deal with the wrapped ring */ + free_write_space = curr_srp - curr_swp; + else + /* The ring has not wrapped yet */ + free_write_space = (curr_srp + bus->m_dwSizeSetRing) - curr_swp; + + dprintk(DBGLVL_BUS, "%s() bytes_to_write = %d\n", __func__, + bytes_to_write); + + dprintk(DBGLVL_BUS, "%s() free_write_space = %d\n", __func__, + free_write_space); + + dprintk(DBGLVL_BUS, "%s() curr_srp = %x\n", __func__, curr_srp); + dprintk(DBGLVL_BUS, "%s() curr_swp = %x\n", __func__, curr_swp); + + /* Process the msg and write the content onto the bus */ + while (bytes_to_write >= free_write_space) { + + if (timeout-- == 0) { + printk(KERN_ERR "%s() bus timeout\n", __func__); + ret = SAA_ERR_NO_RESOURCES; + goto out; + } + + /* TODO: Review this delay, efficient? */ + /* Wait, allowing the hardware fetch time */ + mdelay(1); + + /* Check the space usage again */ + curr_srp = saa7164_readl(bus->m_dwSetReadPos); + + /* Deal with ring wrapping issues */ + if (curr_srp > curr_swp) + /* Deal with the wrapped ring */ + free_write_space = curr_srp - curr_swp; + else + /* Read didn't wrap around the buffer */ + free_write_space = (curr_srp + bus->m_dwSizeSetRing) - + curr_swp; + + } + + /* Calculate the new write position */ + new_swp = curr_swp + bytes_to_write; + + dprintk(DBGLVL_BUS, "%s() new_swp = %x\n", __func__, new_swp); + dprintk(DBGLVL_BUS, "%s() bus->m_dwSizeSetRing = %x\n", __func__, + bus->m_dwSizeSetRing); + + /* + * Make a copy of msg->size before it is converted to le16 since it is + * used in the code below. + */ + size = msg->size; + /* Convert to le16/le32 */ + msg->size = (__force u16)cpu_to_le16(msg->size); + msg->command = (__force u32)cpu_to_le32(msg->command); + msg->controlselector = (__force u16)cpu_to_le16(msg->controlselector); + + /* Mental Note: line 462 tmmhComResBusPCIe.cpp */ + + /* Check if we're going to wrap again */ + if (new_swp > bus->m_dwSizeSetRing) { + + /* Ring wraps */ + new_swp -= bus->m_dwSizeSetRing; + + space_rem = bus->m_dwSizeSetRing - curr_swp; + + dprintk(DBGLVL_BUS, "%s() space_rem = %x\n", __func__, + space_rem); + + dprintk(DBGLVL_BUS, "%s() sizeof(*msg) = %d\n", __func__, + (u32)sizeof(*msg)); + + if (space_rem < sizeof(*msg)) { + dprintk(DBGLVL_BUS, "%s() tr4\n", __func__); + + /* Split the msg into pieces as the ring wraps */ + memcpy_toio(bus->m_pdwSetRing + curr_swp, msg, space_rem); + memcpy_toio(bus->m_pdwSetRing, (u8 *)msg + space_rem, + sizeof(*msg) - space_rem); + + memcpy_toio(bus->m_pdwSetRing + sizeof(*msg) - space_rem, + buf, size); + + } else if (space_rem == sizeof(*msg)) { + dprintk(DBGLVL_BUS, "%s() tr5\n", __func__); + + /* Additional data at the beginning of the ring */ + memcpy_toio(bus->m_pdwSetRing + curr_swp, msg, sizeof(*msg)); + memcpy_toio(bus->m_pdwSetRing, buf, size); + + } else { + /* Additional data wraps around the ring */ + memcpy_toio(bus->m_pdwSetRing + curr_swp, msg, sizeof(*msg)); + if (size > 0) { + memcpy_toio(bus->m_pdwSetRing + curr_swp + + sizeof(*msg), buf, space_rem - + sizeof(*msg)); + memcpy_toio(bus->m_pdwSetRing, (u8 *)buf + + space_rem - sizeof(*msg), + bytes_to_write - space_rem); + } + + } + + } /* (new_swp > bus->m_dwSizeSetRing) */ + else { + dprintk(DBGLVL_BUS, "%s() tr6\n", __func__); + + /* The ring buffer doesn't wrap, two simple copies */ + memcpy_toio(bus->m_pdwSetRing + curr_swp, msg, sizeof(*msg)); + memcpy_toio(bus->m_pdwSetRing + curr_swp + sizeof(*msg), buf, + size); + } + + dprintk(DBGLVL_BUS, "%s() new_swp = %x\n", __func__, new_swp); + + /* Update the bus write position */ + saa7164_writel(bus->m_dwSetWritePos, new_swp); + + /* Convert back to cpu after writing the msg to the ringbuffer. */ + msg->size = le16_to_cpu((__force __le16)msg->size); + msg->command = le32_to_cpu((__force __le32)msg->command); + msg->controlselector = le16_to_cpu((__force __le16)msg->controlselector); + ret = SAA_OK; + +out: + saa7164_bus_dump(dev); + mutex_unlock(&bus->lock); + saa7164_bus_verify(dev); + return ret; +} + +/* + * Receive a command or a response from the bus. The implementation does not + * know if it is a command or a response it simply dequeues the data, + * depending on the bus information given in the struct tmComResBusInfo + * structure. + * + * Return Value: + * 0 The function executed successfully. + * < 0 One or more members are not initialized. + */ +int saa7164_bus_get(struct saa7164_dev *dev, struct tmComResInfo* msg, + void *buf, int peekonly) +{ + struct tmComResBusInfo *bus = &dev->bus; + u32 bytes_to_read, write_distance, curr_grp, curr_gwp, + new_grp, buf_size, space_rem; + struct tmComResInfo msg_tmp; + int ret = SAA_ERR_BAD_PARAMETER; + + saa7164_bus_verify(dev); + + if (msg == NULL) + return ret; + + if (msg->size > dev->bus.m_wMaxReqSize) { + printk(KERN_ERR "%s() Exceeded dev->bus.m_wMaxReqSize\n", + __func__); + return ret; + } + + if ((peekonly == 0) && (msg->size > 0) && (buf == NULL)) { + printk(KERN_ERR + "%s() Missing msg buf, size should be %d bytes\n", + __func__, msg->size); + return ret; + } + + mutex_lock(&bus->lock); + + /* Peek the bus to see if a msg exists, if it's not what we're expecting + * then return cleanly else read the message from the bus. + */ + curr_gwp = saa7164_readl(bus->m_dwGetWritePos); + curr_grp = saa7164_readl(bus->m_dwGetReadPos); + + if (curr_gwp == curr_grp) { + ret = SAA_ERR_EMPTY; + goto out; + } + + bytes_to_read = sizeof(*msg); + + /* Calculate write distance to current read position */ + write_distance = 0; + if (curr_gwp >= curr_grp) + /* Write doesn't wrap around the ring */ + write_distance = curr_gwp - curr_grp; + else + /* Write wraps around the ring */ + write_distance = curr_gwp + bus->m_dwSizeGetRing - curr_grp; + + if (bytes_to_read > write_distance) { + printk(KERN_ERR "%s() No message/response found\n", __func__); + ret = SAA_ERR_INVALID_COMMAND; + goto out; + } + + /* Calculate the new read position */ + new_grp = curr_grp + bytes_to_read; + if (new_grp > bus->m_dwSizeGetRing) { + + /* Ring wraps */ + new_grp -= bus->m_dwSizeGetRing; + space_rem = bus->m_dwSizeGetRing - curr_grp; + + memcpy_fromio(&msg_tmp, bus->m_pdwGetRing + curr_grp, space_rem); + memcpy_fromio((u8 *)&msg_tmp + space_rem, bus->m_pdwGetRing, + bytes_to_read - space_rem); + + } else { + /* No wrapping */ + memcpy_fromio(&msg_tmp, bus->m_pdwGetRing + curr_grp, bytes_to_read); + } + /* Convert from little endian to CPU */ + msg_tmp.size = le16_to_cpu((__force __le16)msg_tmp.size); + msg_tmp.command = le32_to_cpu((__force __le32)msg_tmp.command); + msg_tmp.controlselector = le16_to_cpu((__force __le16)msg_tmp.controlselector); + memcpy(msg, &msg_tmp, sizeof(*msg)); + + /* No need to update the read positions, because this was a peek */ + /* If the caller specifically want to peek, return */ + if (peekonly) { + goto peekout; + } + + /* Check if the command/response matches what is expected */ + if ((msg_tmp.id != msg->id) || (msg_tmp.command != msg->command) || + (msg_tmp.controlselector != msg->controlselector) || + (msg_tmp.seqno != msg->seqno) || (msg_tmp.size != msg->size)) { + + printk(KERN_ERR "%s() Unexpected msg miss-match\n", __func__); + saa7164_bus_dumpmsg(dev, msg, buf); + saa7164_bus_dumpmsg(dev, &msg_tmp, NULL); + ret = SAA_ERR_INVALID_COMMAND; + goto out; + } + + /* Get the actual command and response from the bus */ + buf_size = msg->size; + + bytes_to_read = sizeof(*msg) + msg->size; + /* Calculate write distance to current read position */ + write_distance = 0; + if (curr_gwp >= curr_grp) + /* Write doesn't wrap around the ring */ + write_distance = curr_gwp - curr_grp; + else + /* Write wraps around the ring */ + write_distance = curr_gwp + bus->m_dwSizeGetRing - curr_grp; + + if (bytes_to_read > write_distance) { + printk(KERN_ERR "%s() Invalid bus state, missing msg or mangled ring, faulty H/W / bad code?\n", + __func__); + ret = SAA_ERR_INVALID_COMMAND; + goto out; + } + + /* Calculate the new read position */ + new_grp = curr_grp + bytes_to_read; + if (new_grp > bus->m_dwSizeGetRing) { + + /* Ring wraps */ + new_grp -= bus->m_dwSizeGetRing; + space_rem = bus->m_dwSizeGetRing - curr_grp; + + if (space_rem < sizeof(*msg)) { + if (buf) + memcpy_fromio(buf, bus->m_pdwGetRing + sizeof(*msg) - + space_rem, buf_size); + + } else if (space_rem == sizeof(*msg)) { + if (buf) + memcpy_fromio(buf, bus->m_pdwGetRing, buf_size); + } else { + /* Additional data wraps around the ring */ + if (buf) { + memcpy_fromio(buf, bus->m_pdwGetRing + curr_grp + + sizeof(*msg), space_rem - sizeof(*msg)); + memcpy_fromio(buf + space_rem - sizeof(*msg), + bus->m_pdwGetRing, bytes_to_read - + space_rem); + } + + } + + } else { + /* No wrapping */ + if (buf) + memcpy_fromio(buf, bus->m_pdwGetRing + curr_grp + sizeof(*msg), + buf_size); + } + + /* Update the read positions, adjusting the ring */ + saa7164_writel(bus->m_dwGetReadPos, new_grp); + +peekout: + ret = SAA_OK; +out: + mutex_unlock(&bus->lock); + saa7164_bus_verify(dev); + return ret; +} + -- cgit v1.2.3