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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-stm32.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-stm32.c')
-rw-r--r--drivers/clocksource/timer-stm32.c336
1 files changed, 336 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-stm32.c b/drivers/clocksource/timer-stm32.c
new file mode 100644
index 000000000..c9a753f96
--- /dev/null
+++ b/drivers/clocksource/timer-stm32.c
@@ -0,0 +1,336 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) Maxime Coquelin 2015
+ * Author: Maxime Coquelin <mcoquelin.stm32@gmail.com>
+ *
+ * Inspired by time-efm32.c from Uwe Kleine-Koenig
+ */
+
+#include <linux/kernel.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+#include <linux/reset.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+
+#include "timer-of.h"
+
+#define TIM_CR1 0x00
+#define TIM_DIER 0x0c
+#define TIM_SR 0x10
+#define TIM_EGR 0x14
+#define TIM_CNT 0x24
+#define TIM_PSC 0x28
+#define TIM_ARR 0x2c
+#define TIM_CCR1 0x34
+
+#define TIM_CR1_CEN BIT(0)
+#define TIM_CR1_UDIS BIT(1)
+#define TIM_CR1_OPM BIT(3)
+#define TIM_CR1_ARPE BIT(7)
+
+#define TIM_DIER_UIE BIT(0)
+#define TIM_DIER_CC1IE BIT(1)
+
+#define TIM_SR_UIF BIT(0)
+
+#define TIM_EGR_UG BIT(0)
+
+#define TIM_PSC_MAX USHRT_MAX
+#define TIM_PSC_CLKRATE 10000
+
+struct stm32_timer_private {
+ int bits;
+};
+
+/**
+ * stm32_timer_of_bits_set - set accessor helper
+ * @to: a timer_of structure pointer
+ * @bits: the number of bits (16 or 32)
+ *
+ * Accessor helper to set the number of bits in the timer-of private
+ * structure.
+ *
+ */
+static void stm32_timer_of_bits_set(struct timer_of *to, int bits)
+{
+ struct stm32_timer_private *pd = to->private_data;
+
+ pd->bits = bits;
+}
+
+/**
+ * stm32_timer_of_bits_get - get accessor helper
+ * @to: a timer_of structure pointer
+ *
+ * Accessor helper to get the number of bits in the timer-of private
+ * structure.
+ *
+ * Returns an integer corresponding to the number of bits.
+ */
+static int stm32_timer_of_bits_get(struct timer_of *to)
+{
+ struct stm32_timer_private *pd = to->private_data;
+
+ return pd->bits;
+}
+
+static void __iomem *stm32_timer_cnt __read_mostly;
+
+static u64 notrace stm32_read_sched_clock(void)
+{
+ return readl_relaxed(stm32_timer_cnt);
+}
+
+static struct delay_timer stm32_timer_delay;
+
+static unsigned long stm32_read_delay(void)
+{
+ return readl_relaxed(stm32_timer_cnt);
+}
+
+static void stm32_clock_event_disable(struct timer_of *to)
+{
+ writel_relaxed(0, timer_of_base(to) + TIM_DIER);
+}
+
+/**
+ * stm32_timer_start - Start the counter without event
+ * @to: a timer_of structure pointer
+ *
+ * Start the timer in order to have the counter reset and start
+ * incrementing but disable interrupt event when there is a counter
+ * overflow. By default, the counter direction is used as upcounter.
+ */
+static void stm32_timer_start(struct timer_of *to)
+{
+ writel_relaxed(TIM_CR1_UDIS | TIM_CR1_CEN, timer_of_base(to) + TIM_CR1);
+}
+
+static int stm32_clock_event_shutdown(struct clock_event_device *clkevt)
+{
+ struct timer_of *to = to_timer_of(clkevt);
+
+ stm32_clock_event_disable(to);
+
+ return 0;
+}
+
+static int stm32_clock_event_set_next_event(unsigned long evt,
+ struct clock_event_device *clkevt)
+{
+ struct timer_of *to = to_timer_of(clkevt);
+ unsigned long now, next;
+
+ next = readl_relaxed(timer_of_base(to) + TIM_CNT) + evt;
+ writel_relaxed(next, timer_of_base(to) + TIM_CCR1);
+ now = readl_relaxed(timer_of_base(to) + TIM_CNT);
+
+ if ((next - now) > evt)
+ return -ETIME;
+
+ writel_relaxed(TIM_DIER_CC1IE, timer_of_base(to) + TIM_DIER);
+
+ return 0;
+}
+
+static int stm32_clock_event_set_periodic(struct clock_event_device *clkevt)
+{
+ struct timer_of *to = to_timer_of(clkevt);
+
+ stm32_timer_start(to);
+
+ return stm32_clock_event_set_next_event(timer_of_period(to), clkevt);
+}
+
+static int stm32_clock_event_set_oneshot(struct clock_event_device *clkevt)
+{
+ struct timer_of *to = to_timer_of(clkevt);
+
+ stm32_timer_start(to);
+
+ return 0;
+}
+
+static irqreturn_t stm32_clock_event_handler(int irq, void *dev_id)
+{
+ struct clock_event_device *clkevt = (struct clock_event_device *)dev_id;
+ struct timer_of *to = to_timer_of(clkevt);
+
+ writel_relaxed(0, timer_of_base(to) + TIM_SR);
+
+ if (clockevent_state_periodic(clkevt))
+ stm32_clock_event_set_periodic(clkevt);
+ else
+ stm32_clock_event_shutdown(clkevt);
+
+ clkevt->event_handler(clkevt);
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * stm32_timer_width - Sort out the timer width (32/16)
+ * @to: a pointer to a timer-of structure
+ *
+ * Write the 32-bit max value and read/return the result. If the timer
+ * is 32 bits wide, the result will be UINT_MAX, otherwise it will
+ * be truncated by the 16-bit register to USHRT_MAX.
+ *
+ */
+static void __init stm32_timer_set_width(struct timer_of *to)
+{
+ u32 width;
+
+ writel_relaxed(UINT_MAX, timer_of_base(to) + TIM_ARR);
+
+ width = readl_relaxed(timer_of_base(to) + TIM_ARR);
+
+ stm32_timer_of_bits_set(to, width == UINT_MAX ? 32 : 16);
+}
+
+/**
+ * stm32_timer_set_prescaler - Compute and set the prescaler register
+ * @to: a pointer to a timer-of structure
+ *
+ * Depending on the timer width, compute the prescaler to always
+ * target a 10MHz timer rate for 16 bits. 32-bit timers are
+ * considered precise and long enough to not use the prescaler.
+ */
+static void __init stm32_timer_set_prescaler(struct timer_of *to)
+{
+ int prescaler = 1;
+
+ if (stm32_timer_of_bits_get(to) != 32) {
+ prescaler = DIV_ROUND_CLOSEST(timer_of_rate(to),
+ TIM_PSC_CLKRATE);
+ /*
+ * The prescaler register is an u16, the variable
+ * can't be greater than TIM_PSC_MAX, let's cap it in
+ * this case.
+ */
+ prescaler = prescaler < TIM_PSC_MAX ? prescaler : TIM_PSC_MAX;
+ }
+
+ writel_relaxed(prescaler - 1, timer_of_base(to) + TIM_PSC);
+ writel_relaxed(TIM_EGR_UG, timer_of_base(to) + TIM_EGR);
+ writel_relaxed(0, timer_of_base(to) + TIM_SR);
+
+ /* Adjust rate and period given the prescaler value */
+ to->of_clk.rate = DIV_ROUND_CLOSEST(to->of_clk.rate, prescaler);
+ to->of_clk.period = DIV_ROUND_UP(to->of_clk.rate, HZ);
+}
+
+static int __init stm32_clocksource_init(struct timer_of *to)
+{
+ u32 bits = stm32_timer_of_bits_get(to);
+ const char *name = to->np->full_name;
+
+ /*
+ * This driver allows to register several timers and relies on
+ * the generic time framework to select the right one.
+ * However, nothing allows to do the same for the
+ * sched_clock. We are not interested in a sched_clock for the
+ * 16-bit timers but only for the 32-bit one, so if no 32-bit
+ * timer is registered yet, we select this 32-bit timer as a
+ * sched_clock.
+ */
+ if (bits == 32 && !stm32_timer_cnt) {
+
+ /*
+ * Start immediately the counter as we will be using
+ * it right after.
+ */
+ stm32_timer_start(to);
+
+ stm32_timer_cnt = timer_of_base(to) + TIM_CNT;
+ sched_clock_register(stm32_read_sched_clock, bits, timer_of_rate(to));
+ pr_info("%s: STM32 sched_clock registered\n", name);
+
+ stm32_timer_delay.read_current_timer = stm32_read_delay;
+ stm32_timer_delay.freq = timer_of_rate(to);
+ register_current_timer_delay(&stm32_timer_delay);
+ pr_info("%s: STM32 delay timer registered\n", name);
+ }
+
+ return clocksource_mmio_init(timer_of_base(to) + TIM_CNT, name,
+ timer_of_rate(to), bits == 32 ? 250 : 100,
+ bits, clocksource_mmio_readl_up);
+}
+
+static void __init stm32_clockevent_init(struct timer_of *to)
+{
+ u32 bits = stm32_timer_of_bits_get(to);
+
+ to->clkevt.name = to->np->full_name;
+ to->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
+ to->clkevt.set_state_shutdown = stm32_clock_event_shutdown;
+ to->clkevt.set_state_periodic = stm32_clock_event_set_periodic;
+ to->clkevt.set_state_oneshot = stm32_clock_event_set_oneshot;
+ to->clkevt.tick_resume = stm32_clock_event_shutdown;
+ to->clkevt.set_next_event = stm32_clock_event_set_next_event;
+ to->clkevt.rating = bits == 32 ? 250 : 100;
+
+ clockevents_config_and_register(&to->clkevt, timer_of_rate(to), 0x1,
+ (1 << bits) - 1);
+
+ pr_info("%pOF: STM32 clockevent driver initialized (%d bits)\n",
+ to->np, bits);
+}
+
+static int __init stm32_timer_init(struct device_node *node)
+{
+ struct reset_control *rstc;
+ struct timer_of *to;
+ int ret;
+
+ to = kzalloc(sizeof(*to), GFP_KERNEL);
+ if (!to)
+ return -ENOMEM;
+
+ to->flags = TIMER_OF_IRQ | TIMER_OF_CLOCK | TIMER_OF_BASE;
+ to->of_irq.handler = stm32_clock_event_handler;
+
+ ret = timer_of_init(node, to);
+ if (ret)
+ goto err;
+
+ to->private_data = kzalloc(sizeof(struct stm32_timer_private),
+ GFP_KERNEL);
+ if (!to->private_data) {
+ ret = -ENOMEM;
+ goto deinit;
+ }
+
+ rstc = of_reset_control_get(node, NULL);
+ if (!IS_ERR(rstc)) {
+ reset_control_assert(rstc);
+ reset_control_deassert(rstc);
+ }
+
+ stm32_timer_set_width(to);
+
+ stm32_timer_set_prescaler(to);
+
+ ret = stm32_clocksource_init(to);
+ if (ret)
+ goto deinit;
+
+ stm32_clockevent_init(to);
+ return 0;
+
+deinit:
+ timer_of_cleanup(to);
+err:
+ kfree(to);
+ return ret;
+}
+
+TIMER_OF_DECLARE(stm32, "st,stm32-timer", stm32_timer_init);