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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/clocksource/timer-atmel-pit.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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 'drivers/clocksource/timer-atmel-pit.c')
-rw-r--r--drivers/clocksource/timer-atmel-pit.c264
1 files changed, 264 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-atmel-pit.c b/drivers/clocksource/timer-atmel-pit.c
new file mode 100644
index 000000000..b4f264ed1
--- /dev/null
+++ b/drivers/clocksource/timer-atmel-pit.c
@@ -0,0 +1,264 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * at91sam926x_time.c - Periodic Interval Timer (PIT) for at91sam926x
+ *
+ * Copyright (C) 2005-2006 M. Amine SAYA, ATMEL Rousset, France
+ * Revision 2005 M. Nicolas Diremdjian, ATMEL Rousset, France
+ * Converted to ClockSource/ClockEvents by David Brownell.
+ */
+
+#define pr_fmt(fmt) "AT91: PIT: " fmt
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/slab.h>
+
+#define AT91_PIT_MR 0x00 /* Mode Register */
+#define AT91_PIT_PITIEN BIT(25) /* Timer Interrupt Enable */
+#define AT91_PIT_PITEN BIT(24) /* Timer Enabled */
+#define AT91_PIT_PIV GENMASK(19, 0) /* Periodic Interval Value */
+
+#define AT91_PIT_SR 0x04 /* Status Register */
+#define AT91_PIT_PITS BIT(0) /* Timer Status */
+
+#define AT91_PIT_PIVR 0x08 /* Periodic Interval Value Register */
+#define AT91_PIT_PIIR 0x0c /* Periodic Interval Image Register */
+#define AT91_PIT_PICNT GENMASK(31, 20) /* Interval Counter */
+#define AT91_PIT_CPIV GENMASK(19, 0) /* Inverval Value */
+
+#define PIT_CPIV(x) ((x) & AT91_PIT_CPIV)
+#define PIT_PICNT(x) (((x) & AT91_PIT_PICNT) >> 20)
+
+struct pit_data {
+ struct clock_event_device clkevt;
+ struct clocksource clksrc;
+
+ void __iomem *base;
+ u32 cycle;
+ u32 cnt;
+ unsigned int irq;
+ struct clk *mck;
+};
+
+static inline struct pit_data *clksrc_to_pit_data(struct clocksource *clksrc)
+{
+ return container_of(clksrc, struct pit_data, clksrc);
+}
+
+static inline struct pit_data *clkevt_to_pit_data(struct clock_event_device *clkevt)
+{
+ return container_of(clkevt, struct pit_data, clkevt);
+}
+
+static inline unsigned int pit_read(void __iomem *base, unsigned int reg_offset)
+{
+ return readl_relaxed(base + reg_offset);
+}
+
+static inline void pit_write(void __iomem *base, unsigned int reg_offset, unsigned long value)
+{
+ writel_relaxed(value, base + reg_offset);
+}
+
+/*
+ * Clocksource: just a monotonic counter of MCK/16 cycles.
+ * We don't care whether or not PIT irqs are enabled.
+ */
+static u64 read_pit_clk(struct clocksource *cs)
+{
+ struct pit_data *data = clksrc_to_pit_data(cs);
+ unsigned long flags;
+ u32 elapsed;
+ u32 t;
+
+ raw_local_irq_save(flags);
+ elapsed = data->cnt;
+ t = pit_read(data->base, AT91_PIT_PIIR);
+ raw_local_irq_restore(flags);
+
+ elapsed += PIT_PICNT(t) * data->cycle;
+ elapsed += PIT_CPIV(t);
+ return elapsed;
+}
+
+static int pit_clkevt_shutdown(struct clock_event_device *dev)
+{
+ struct pit_data *data = clkevt_to_pit_data(dev);
+
+ /* disable irq, leaving the clocksource active */
+ pit_write(data->base, AT91_PIT_MR, (data->cycle - 1) | AT91_PIT_PITEN);
+ return 0;
+}
+
+/*
+ * Clockevent device: interrupts every 1/HZ (== pit_cycles * MCK/16)
+ */
+static int pit_clkevt_set_periodic(struct clock_event_device *dev)
+{
+ struct pit_data *data = clkevt_to_pit_data(dev);
+
+ /* update clocksource counter */
+ data->cnt += data->cycle * PIT_PICNT(pit_read(data->base, AT91_PIT_PIVR));
+ pit_write(data->base, AT91_PIT_MR,
+ (data->cycle - 1) | AT91_PIT_PITEN | AT91_PIT_PITIEN);
+ return 0;
+}
+
+static void at91sam926x_pit_suspend(struct clock_event_device *cedev)
+{
+ struct pit_data *data = clkevt_to_pit_data(cedev);
+
+ /* Disable timer */
+ pit_write(data->base, AT91_PIT_MR, 0);
+}
+
+static void at91sam926x_pit_reset(struct pit_data *data)
+{
+ /* Disable timer and irqs */
+ pit_write(data->base, AT91_PIT_MR, 0);
+
+ /* Clear any pending interrupts, wait for PIT to stop counting */
+ while (PIT_CPIV(pit_read(data->base, AT91_PIT_PIVR)) != 0)
+ cpu_relax();
+
+ /* Start PIT but don't enable IRQ */
+ pit_write(data->base, AT91_PIT_MR,
+ (data->cycle - 1) | AT91_PIT_PITEN);
+}
+
+static void at91sam926x_pit_resume(struct clock_event_device *cedev)
+{
+ struct pit_data *data = clkevt_to_pit_data(cedev);
+
+ at91sam926x_pit_reset(data);
+}
+
+/*
+ * IRQ handler for the timer.
+ */
+static irqreturn_t at91sam926x_pit_interrupt(int irq, void *dev_id)
+{
+ struct pit_data *data = dev_id;
+
+ /* The PIT interrupt may be disabled, and is shared */
+ if (clockevent_state_periodic(&data->clkevt) &&
+ (pit_read(data->base, AT91_PIT_SR) & AT91_PIT_PITS)) {
+ /* Get number of ticks performed before irq, and ack it */
+ data->cnt += data->cycle * PIT_PICNT(pit_read(data->base,
+ AT91_PIT_PIVR));
+ data->clkevt.event_handler(&data->clkevt);
+
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
+/*
+ * Set up both clocksource and clockevent support.
+ */
+static int __init at91sam926x_pit_dt_init(struct device_node *node)
+{
+ unsigned long pit_rate;
+ unsigned bits;
+ int ret;
+ struct pit_data *data;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->base = of_iomap(node, 0);
+ if (!data->base) {
+ pr_err("Could not map PIT address\n");
+ ret = -ENXIO;
+ goto exit;
+ }
+
+ data->mck = of_clk_get(node, 0);
+ if (IS_ERR(data->mck)) {
+ pr_err("Unable to get mck clk\n");
+ ret = PTR_ERR(data->mck);
+ goto exit;
+ }
+
+ ret = clk_prepare_enable(data->mck);
+ if (ret) {
+ pr_err("Unable to enable mck\n");
+ goto exit;
+ }
+
+ /* Get the interrupts property */
+ data->irq = irq_of_parse_and_map(node, 0);
+ if (!data->irq) {
+ pr_err("Unable to get IRQ from DT\n");
+ ret = -EINVAL;
+ goto exit;
+ }
+
+ /*
+ * Use our actual MCK to figure out how many MCK/16 ticks per
+ * 1/HZ period (instead of a compile-time constant LATCH).
+ */
+ pit_rate = clk_get_rate(data->mck) / 16;
+ data->cycle = DIV_ROUND_CLOSEST(pit_rate, HZ);
+ WARN_ON(((data->cycle - 1) & ~AT91_PIT_PIV) != 0);
+
+ /* Initialize and enable the timer */
+ at91sam926x_pit_reset(data);
+
+ /*
+ * Register clocksource. The high order bits of PIV are unused,
+ * so this isn't a 32-bit counter unless we get clockevent irqs.
+ */
+ bits = 12 /* PICNT */ + ilog2(data->cycle) /* PIV */;
+ data->clksrc.mask = CLOCKSOURCE_MASK(bits);
+ data->clksrc.name = "pit";
+ data->clksrc.rating = 175;
+ data->clksrc.read = read_pit_clk;
+ data->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+
+ ret = clocksource_register_hz(&data->clksrc, pit_rate);
+ if (ret) {
+ pr_err("Failed to register clocksource\n");
+ goto exit;
+ }
+
+ /* Set up irq handler */
+ ret = request_irq(data->irq, at91sam926x_pit_interrupt,
+ IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+ "at91_tick", data);
+ if (ret) {
+ pr_err("Unable to setup IRQ\n");
+ clocksource_unregister(&data->clksrc);
+ goto exit;
+ }
+
+ /* Set up and register clockevents */
+ data->clkevt.name = "pit";
+ data->clkevt.features = CLOCK_EVT_FEAT_PERIODIC;
+ data->clkevt.shift = 32;
+ data->clkevt.mult = div_sc(pit_rate, NSEC_PER_SEC, data->clkevt.shift);
+ data->clkevt.rating = 100;
+ data->clkevt.cpumask = cpumask_of(0);
+
+ data->clkevt.set_state_shutdown = pit_clkevt_shutdown;
+ data->clkevt.set_state_periodic = pit_clkevt_set_periodic;
+ data->clkevt.resume = at91sam926x_pit_resume;
+ data->clkevt.suspend = at91sam926x_pit_suspend;
+ clockevents_register_device(&data->clkevt);
+
+ return 0;
+
+exit:
+ kfree(data);
+ return ret;
+}
+TIMER_OF_DECLARE(at91sam926x_pit, "atmel,at91sam9260-pit",
+ at91sam926x_pit_dt_init);