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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-tcb.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 'drivers/clocksource/timer-atmel-tcb.c')
-rw-r--r--drivers/clocksource/timer-atmel-tcb.c510
1 files changed, 510 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-atmel-tcb.c b/drivers/clocksource/timer-atmel-tcb.c
new file mode 100644
index 000000000..27af17c99
--- /dev/null
+++ b/drivers/clocksource/timer-atmel-tcb.c
@@ -0,0 +1,510 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+#include <linux/syscore_ops.h>
+#include <soc/at91/atmel_tcb.h>
+
+
+/*
+ * We're configured to use a specific TC block, one that's not hooked
+ * up to external hardware, to provide a time solution:
+ *
+ * - Two channels combine to create a free-running 32 bit counter
+ * with a base rate of 5+ MHz, packaged as a clocksource (with
+ * resolution better than 200 nsec).
+ * - Some chips support 32 bit counter. A single channel is used for
+ * this 32 bit free-running counter. the second channel is not used.
+ *
+ * - The third channel may be used to provide a clockevent source, used in
+ * either periodic or oneshot mode. For 16-bit counter its runs at 32 KiHZ,
+ * and can handle delays of up to two seconds. For 32-bit counters, it runs at
+ * the same rate as the clocksource
+ *
+ * REVISIT behavior during system suspend states... we should disable
+ * all clocks and save the power. Easily done for clockevent devices,
+ * but clocksources won't necessarily get the needed notifications.
+ * For deeper system sleep states, this will be mandatory...
+ */
+
+static void __iomem *tcaddr;
+static struct
+{
+ u32 cmr;
+ u32 imr;
+ u32 rc;
+ bool clken;
+} tcb_cache[3];
+static u32 bmr_cache;
+
+static const u8 atmel_tcb_divisors[] = { 2, 8, 32, 128 };
+
+static u64 tc_get_cycles(struct clocksource *cs)
+{
+ unsigned long flags;
+ u32 lower, upper;
+
+ raw_local_irq_save(flags);
+ do {
+ upper = readl_relaxed(tcaddr + ATMEL_TC_REG(1, CV));
+ lower = readl_relaxed(tcaddr + ATMEL_TC_REG(0, CV));
+ } while (upper != readl_relaxed(tcaddr + ATMEL_TC_REG(1, CV)));
+
+ raw_local_irq_restore(flags);
+ return (upper << 16) | lower;
+}
+
+static u64 tc_get_cycles32(struct clocksource *cs)
+{
+ return readl_relaxed(tcaddr + ATMEL_TC_REG(0, CV));
+}
+
+static void tc_clksrc_suspend(struct clocksource *cs)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(tcb_cache); i++) {
+ tcb_cache[i].cmr = readl(tcaddr + ATMEL_TC_REG(i, CMR));
+ tcb_cache[i].imr = readl(tcaddr + ATMEL_TC_REG(i, IMR));
+ tcb_cache[i].rc = readl(tcaddr + ATMEL_TC_REG(i, RC));
+ tcb_cache[i].clken = !!(readl(tcaddr + ATMEL_TC_REG(i, SR)) &
+ ATMEL_TC_CLKSTA);
+ }
+
+ bmr_cache = readl(tcaddr + ATMEL_TC_BMR);
+}
+
+static void tc_clksrc_resume(struct clocksource *cs)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(tcb_cache); i++) {
+ /* Restore registers for the channel, RA and RB are not used */
+ writel(tcb_cache[i].cmr, tcaddr + ATMEL_TC_REG(i, CMR));
+ writel(tcb_cache[i].rc, tcaddr + ATMEL_TC_REG(i, RC));
+ writel(0, tcaddr + ATMEL_TC_REG(i, RA));
+ writel(0, tcaddr + ATMEL_TC_REG(i, RB));
+ /* Disable all the interrupts */
+ writel(0xff, tcaddr + ATMEL_TC_REG(i, IDR));
+ /* Reenable interrupts that were enabled before suspending */
+ writel(tcb_cache[i].imr, tcaddr + ATMEL_TC_REG(i, IER));
+ /* Start the clock if it was used */
+ if (tcb_cache[i].clken)
+ writel(ATMEL_TC_CLKEN, tcaddr + ATMEL_TC_REG(i, CCR));
+ }
+
+ /* Dual channel, chain channels */
+ writel(bmr_cache, tcaddr + ATMEL_TC_BMR);
+ /* Finally, trigger all the channels*/
+ writel(ATMEL_TC_SYNC, tcaddr + ATMEL_TC_BCR);
+}
+
+static struct clocksource clksrc = {
+ .rating = 200,
+ .read = tc_get_cycles,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+ .suspend = tc_clksrc_suspend,
+ .resume = tc_clksrc_resume,
+};
+
+static u64 notrace tc_sched_clock_read(void)
+{
+ return tc_get_cycles(&clksrc);
+}
+
+static u64 notrace tc_sched_clock_read32(void)
+{
+ return tc_get_cycles32(&clksrc);
+}
+
+static struct delay_timer tc_delay_timer;
+
+static unsigned long tc_delay_timer_read(void)
+{
+ return tc_get_cycles(&clksrc);
+}
+
+static unsigned long notrace tc_delay_timer_read32(void)
+{
+ return tc_get_cycles32(&clksrc);
+}
+
+#ifdef CONFIG_GENERIC_CLOCKEVENTS
+
+struct tc_clkevt_device {
+ struct clock_event_device clkevt;
+ struct clk *clk;
+ u32 rate;
+ void __iomem *regs;
+};
+
+static struct tc_clkevt_device *to_tc_clkevt(struct clock_event_device *clkevt)
+{
+ return container_of(clkevt, struct tc_clkevt_device, clkevt);
+}
+
+static u32 timer_clock;
+
+static int tc_shutdown(struct clock_event_device *d)
+{
+ struct tc_clkevt_device *tcd = to_tc_clkevt(d);
+ void __iomem *regs = tcd->regs;
+
+ writel(0xff, regs + ATMEL_TC_REG(2, IDR));
+ writel(ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(2, CCR));
+ if (!clockevent_state_detached(d))
+ clk_disable(tcd->clk);
+
+ return 0;
+}
+
+static int tc_set_oneshot(struct clock_event_device *d)
+{
+ struct tc_clkevt_device *tcd = to_tc_clkevt(d);
+ void __iomem *regs = tcd->regs;
+
+ if (clockevent_state_oneshot(d) || clockevent_state_periodic(d))
+ tc_shutdown(d);
+
+ clk_enable(tcd->clk);
+
+ /* count up to RC, then irq and stop */
+ writel(timer_clock | ATMEL_TC_CPCSTOP | ATMEL_TC_WAVE |
+ ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR));
+ writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
+
+ /* set_next_event() configures and starts the timer */
+ return 0;
+}
+
+static int tc_set_periodic(struct clock_event_device *d)
+{
+ struct tc_clkevt_device *tcd = to_tc_clkevt(d);
+ void __iomem *regs = tcd->regs;
+
+ if (clockevent_state_oneshot(d) || clockevent_state_periodic(d))
+ tc_shutdown(d);
+
+ /* By not making the gentime core emulate periodic mode on top
+ * of oneshot, we get lower overhead and improved accuracy.
+ */
+ clk_enable(tcd->clk);
+
+ /* count up to RC, then irq and restart */
+ writel(timer_clock | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO,
+ regs + ATMEL_TC_REG(2, CMR));
+ writel((tcd->rate + HZ / 2) / HZ, tcaddr + ATMEL_TC_REG(2, RC));
+
+ /* Enable clock and interrupts on RC compare */
+ writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
+
+ /* go go gadget! */
+ writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG, regs +
+ ATMEL_TC_REG(2, CCR));
+ return 0;
+}
+
+static int tc_next_event(unsigned long delta, struct clock_event_device *d)
+{
+ writel_relaxed(delta, tcaddr + ATMEL_TC_REG(2, RC));
+
+ /* go go gadget! */
+ writel_relaxed(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG,
+ tcaddr + ATMEL_TC_REG(2, CCR));
+ return 0;
+}
+
+static struct tc_clkevt_device clkevt = {
+ .clkevt = {
+ .features = CLOCK_EVT_FEAT_PERIODIC |
+ CLOCK_EVT_FEAT_ONESHOT,
+ /* Should be lower than at91rm9200's system timer */
+ .rating = 125,
+ .set_next_event = tc_next_event,
+ .set_state_shutdown = tc_shutdown,
+ .set_state_periodic = tc_set_periodic,
+ .set_state_oneshot = tc_set_oneshot,
+ },
+};
+
+static irqreturn_t ch2_irq(int irq, void *handle)
+{
+ struct tc_clkevt_device *dev = handle;
+ unsigned int sr;
+
+ sr = readl_relaxed(dev->regs + ATMEL_TC_REG(2, SR));
+ if (sr & ATMEL_TC_CPCS) {
+ dev->clkevt.event_handler(&dev->clkevt);
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
+static int __init setup_clkevents(struct atmel_tc *tc, int divisor_idx)
+{
+ int ret;
+ struct clk *t2_clk = tc->clk[2];
+ int irq = tc->irq[2];
+ int bits = tc->tcb_config->counter_width;
+
+ /* try to enable t2 clk to avoid future errors in mode change */
+ ret = clk_prepare_enable(t2_clk);
+ if (ret)
+ return ret;
+
+ clkevt.regs = tc->regs;
+ clkevt.clk = t2_clk;
+
+ if (bits == 32) {
+ timer_clock = divisor_idx;
+ clkevt.rate = clk_get_rate(t2_clk) / atmel_tcb_divisors[divisor_idx];
+ } else {
+ ret = clk_prepare_enable(tc->slow_clk);
+ if (ret) {
+ clk_disable_unprepare(t2_clk);
+ return ret;
+ }
+
+ clkevt.rate = clk_get_rate(tc->slow_clk);
+ timer_clock = ATMEL_TC_TIMER_CLOCK5;
+ }
+
+ clk_disable(t2_clk);
+
+ clkevt.clkevt.cpumask = cpumask_of(0);
+
+ ret = request_irq(irq, ch2_irq, IRQF_TIMER, "tc_clkevt", &clkevt);
+ if (ret) {
+ clk_unprepare(t2_clk);
+ if (bits != 32)
+ clk_disable_unprepare(tc->slow_clk);
+ return ret;
+ }
+
+ clockevents_config_and_register(&clkevt.clkevt, clkevt.rate, 1, BIT(bits) - 1);
+
+ return ret;
+}
+
+#else /* !CONFIG_GENERIC_CLOCKEVENTS */
+
+static int __init setup_clkevents(struct atmel_tc *tc, int divisor_idx)
+{
+ /* NOTHING */
+ return 0;
+}
+
+#endif
+
+static void __init tcb_setup_dual_chan(struct atmel_tc *tc, int mck_divisor_idx)
+{
+ /* channel 0: waveform mode, input mclk/8, clock TIOA0 on overflow */
+ writel(mck_divisor_idx /* likely divide-by-8 */
+ | ATMEL_TC_WAVE
+ | ATMEL_TC_WAVESEL_UP /* free-run */
+ | ATMEL_TC_ACPA_SET /* TIOA0 rises at 0 */
+ | ATMEL_TC_ACPC_CLEAR, /* (duty cycle 50%) */
+ tcaddr + ATMEL_TC_REG(0, CMR));
+ writel(0x0000, tcaddr + ATMEL_TC_REG(0, RA));
+ writel(0x8000, tcaddr + ATMEL_TC_REG(0, RC));
+ writel(0xff, tcaddr + ATMEL_TC_REG(0, IDR)); /* no irqs */
+ writel(ATMEL_TC_CLKEN, tcaddr + ATMEL_TC_REG(0, CCR));
+
+ /* channel 1: waveform mode, input TIOA0 */
+ writel(ATMEL_TC_XC1 /* input: TIOA0 */
+ | ATMEL_TC_WAVE
+ | ATMEL_TC_WAVESEL_UP, /* free-run */
+ tcaddr + ATMEL_TC_REG(1, CMR));
+ writel(0xff, tcaddr + ATMEL_TC_REG(1, IDR)); /* no irqs */
+ writel(ATMEL_TC_CLKEN, tcaddr + ATMEL_TC_REG(1, CCR));
+
+ /* chain channel 0 to channel 1*/
+ writel(ATMEL_TC_TC1XC1S_TIOA0, tcaddr + ATMEL_TC_BMR);
+ /* then reset all the timers */
+ writel(ATMEL_TC_SYNC, tcaddr + ATMEL_TC_BCR);
+}
+
+static void __init tcb_setup_single_chan(struct atmel_tc *tc, int mck_divisor_idx)
+{
+ /* channel 0: waveform mode, input mclk/8 */
+ writel(mck_divisor_idx /* likely divide-by-8 */
+ | ATMEL_TC_WAVE
+ | ATMEL_TC_WAVESEL_UP, /* free-run */
+ tcaddr + ATMEL_TC_REG(0, CMR));
+ writel(0xff, tcaddr + ATMEL_TC_REG(0, IDR)); /* no irqs */
+ writel(ATMEL_TC_CLKEN, tcaddr + ATMEL_TC_REG(0, CCR));
+
+ /* then reset all the timers */
+ writel(ATMEL_TC_SYNC, tcaddr + ATMEL_TC_BCR);
+}
+
+static struct atmel_tcb_config tcb_rm9200_config = {
+ .counter_width = 16,
+};
+
+static struct atmel_tcb_config tcb_sam9x5_config = {
+ .counter_width = 32,
+};
+
+static struct atmel_tcb_config tcb_sama5d2_config = {
+ .counter_width = 32,
+ .has_gclk = 1,
+};
+
+static const struct of_device_id atmel_tcb_of_match[] = {
+ { .compatible = "atmel,at91rm9200-tcb", .data = &tcb_rm9200_config, },
+ { .compatible = "atmel,at91sam9x5-tcb", .data = &tcb_sam9x5_config, },
+ { .compatible = "atmel,sama5d2-tcb", .data = &tcb_sama5d2_config, },
+ { /* sentinel */ }
+};
+
+static int __init tcb_clksrc_init(struct device_node *node)
+{
+ struct atmel_tc tc;
+ struct clk *t0_clk;
+ const struct of_device_id *match;
+ u64 (*tc_sched_clock)(void);
+ u32 rate, divided_rate = 0;
+ int best_divisor_idx = -1;
+ int bits;
+ int i;
+ int ret;
+
+ /* Protect against multiple calls */
+ if (tcaddr)
+ return 0;
+
+ tc.regs = of_iomap(node->parent, 0);
+ if (!tc.regs)
+ return -ENXIO;
+
+ t0_clk = of_clk_get_by_name(node->parent, "t0_clk");
+ if (IS_ERR(t0_clk))
+ return PTR_ERR(t0_clk);
+
+ tc.slow_clk = of_clk_get_by_name(node->parent, "slow_clk");
+ if (IS_ERR(tc.slow_clk))
+ return PTR_ERR(tc.slow_clk);
+
+ tc.clk[0] = t0_clk;
+ tc.clk[1] = of_clk_get_by_name(node->parent, "t1_clk");
+ if (IS_ERR(tc.clk[1]))
+ tc.clk[1] = t0_clk;
+ tc.clk[2] = of_clk_get_by_name(node->parent, "t2_clk");
+ if (IS_ERR(tc.clk[2]))
+ tc.clk[2] = t0_clk;
+
+ tc.irq[2] = of_irq_get(node->parent, 2);
+ if (tc.irq[2] <= 0) {
+ tc.irq[2] = of_irq_get(node->parent, 0);
+ if (tc.irq[2] <= 0)
+ return -EINVAL;
+ }
+
+ match = of_match_node(atmel_tcb_of_match, node->parent);
+ if (!match)
+ return -ENODEV;
+
+ tc.tcb_config = match->data;
+ bits = tc.tcb_config->counter_width;
+
+ for (i = 0; i < ARRAY_SIZE(tc.irq); i++)
+ writel(ATMEL_TC_ALL_IRQ, tc.regs + ATMEL_TC_REG(i, IDR));
+
+ ret = clk_prepare_enable(t0_clk);
+ if (ret) {
+ pr_debug("can't enable T0 clk\n");
+ return ret;
+ }
+
+ /* How fast will we be counting? Pick something over 5 MHz. */
+ rate = (u32) clk_get_rate(t0_clk);
+ i = 0;
+ if (tc.tcb_config->has_gclk)
+ i = 1;
+ for (; i < ARRAY_SIZE(atmel_tcb_divisors); i++) {
+ unsigned divisor = atmel_tcb_divisors[i];
+ unsigned tmp;
+
+ tmp = rate / divisor;
+ pr_debug("TC: %u / %-3u [%d] --> %u\n", rate, divisor, i, tmp);
+ if ((best_divisor_idx >= 0) && (tmp < 5 * 1000 * 1000))
+ break;
+ divided_rate = tmp;
+ best_divisor_idx = i;
+ }
+
+ clksrc.name = kbasename(node->parent->full_name);
+ clkevt.clkevt.name = kbasename(node->parent->full_name);
+ pr_debug("%s at %d.%03d MHz\n", clksrc.name, divided_rate / 1000000,
+ ((divided_rate % 1000000) + 500) / 1000);
+
+ tcaddr = tc.regs;
+
+ if (bits == 32) {
+ /* use appropriate function to read 32 bit counter */
+ clksrc.read = tc_get_cycles32;
+ /* setup only channel 0 */
+ tcb_setup_single_chan(&tc, best_divisor_idx);
+ tc_sched_clock = tc_sched_clock_read32;
+ tc_delay_timer.read_current_timer = tc_delay_timer_read32;
+ } else {
+ /* we have three clocks no matter what the
+ * underlying platform supports.
+ */
+ ret = clk_prepare_enable(tc.clk[1]);
+ if (ret) {
+ pr_debug("can't enable T1 clk\n");
+ goto err_disable_t0;
+ }
+ /* setup both channel 0 & 1 */
+ tcb_setup_dual_chan(&tc, best_divisor_idx);
+ tc_sched_clock = tc_sched_clock_read;
+ tc_delay_timer.read_current_timer = tc_delay_timer_read;
+ }
+
+ /* and away we go! */
+ ret = clocksource_register_hz(&clksrc, divided_rate);
+ if (ret)
+ goto err_disable_t1;
+
+ /* channel 2: periodic and oneshot timer support */
+ ret = setup_clkevents(&tc, best_divisor_idx);
+ if (ret)
+ goto err_unregister_clksrc;
+
+ sched_clock_register(tc_sched_clock, 32, divided_rate);
+
+ tc_delay_timer.freq = divided_rate;
+ register_current_timer_delay(&tc_delay_timer);
+
+ return 0;
+
+err_unregister_clksrc:
+ clocksource_unregister(&clksrc);
+
+err_disable_t1:
+ if (bits != 32)
+ clk_disable_unprepare(tc.clk[1]);
+
+err_disable_t0:
+ clk_disable_unprepare(t0_clk);
+
+ tcaddr = NULL;
+
+ return ret;
+}
+TIMER_OF_DECLARE(atmel_tcb_clksrc, "atmel,tcb-timer", tcb_clksrc_init);