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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 /arch/arc/kernel/mcip.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 'arch/arc/kernel/mcip.c')
-rw-r--r--arch/arc/kernel/mcip.c421
1 files changed, 421 insertions, 0 deletions
diff --git a/arch/arc/kernel/mcip.c b/arch/arc/kernel/mcip.c
new file mode 100644
index 000000000..f9fdb557c
--- /dev/null
+++ b/arch/arc/kernel/mcip.c
@@ -0,0 +1,421 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ARC ARConnect (MultiCore IP) support (formerly known as MCIP)
+ *
+ * Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/smp.h>
+#include <linux/irq.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/spinlock.h>
+#include <soc/arc/mcip.h>
+#include <asm/irqflags-arcv2.h>
+#include <asm/setup.h>
+
+static DEFINE_RAW_SPINLOCK(mcip_lock);
+
+#ifdef CONFIG_SMP
+
+static char smp_cpuinfo_buf[128];
+
+/*
+ * Set mask to halt GFRC if any online core in SMP cluster is halted.
+ * Only works for ARC HS v3.0+, on earlier versions has no effect.
+ */
+static void mcip_update_gfrc_halt_mask(int cpu)
+{
+ struct bcr_generic gfrc;
+ unsigned long flags;
+ u32 gfrc_halt_mask;
+
+ READ_BCR(ARC_REG_GFRC_BUILD, gfrc);
+
+ /*
+ * CMD_GFRC_SET_CORE and CMD_GFRC_READ_CORE commands were added in
+ * GFRC 0x3 version.
+ */
+ if (gfrc.ver < 0x3)
+ return;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+
+ __mcip_cmd(CMD_GFRC_READ_CORE, 0);
+ gfrc_halt_mask = read_aux_reg(ARC_REG_MCIP_READBACK);
+ gfrc_halt_mask |= BIT(cpu);
+ __mcip_cmd_data(CMD_GFRC_SET_CORE, 0, gfrc_halt_mask);
+
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void mcip_update_debug_halt_mask(int cpu)
+{
+ u32 mcip_mask = 0;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+
+ /*
+ * mcip_mask is same for CMD_DEBUG_SET_SELECT and CMD_DEBUG_SET_MASK
+ * commands. So read it once instead of reading both CMD_DEBUG_READ_MASK
+ * and CMD_DEBUG_READ_SELECT.
+ */
+ __mcip_cmd(CMD_DEBUG_READ_SELECT, 0);
+ mcip_mask = read_aux_reg(ARC_REG_MCIP_READBACK);
+
+ mcip_mask |= BIT(cpu);
+
+ __mcip_cmd_data(CMD_DEBUG_SET_SELECT, 0, mcip_mask);
+ /*
+ * Parameter specified halt cause:
+ * STATUS32[H]/actionpoint/breakpoint/self-halt
+ * We choose all of them (0xF).
+ */
+ __mcip_cmd_data(CMD_DEBUG_SET_MASK, 0xF, mcip_mask);
+
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void mcip_setup_per_cpu(int cpu)
+{
+ struct mcip_bcr mp;
+
+ READ_BCR(ARC_REG_MCIP_BCR, mp);
+
+ smp_ipi_irq_setup(cpu, IPI_IRQ);
+ smp_ipi_irq_setup(cpu, SOFTIRQ_IRQ);
+
+ /* Update GFRC halt mask as new CPU came online */
+ if (mp.gfrc)
+ mcip_update_gfrc_halt_mask(cpu);
+
+ /* Update MCIP debug mask as new CPU came online */
+ if (mp.dbg)
+ mcip_update_debug_halt_mask(cpu);
+}
+
+static void mcip_ipi_send(int cpu)
+{
+ unsigned long flags;
+ int ipi_was_pending;
+
+ /* ARConnect can only send IPI to others */
+ if (unlikely(cpu == raw_smp_processor_id())) {
+ arc_softirq_trigger(SOFTIRQ_IRQ);
+ return;
+ }
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+
+ /*
+ * If receiver already has a pending interrupt, elide sending this one.
+ * Linux cross core calling works well with concurrent IPIs
+ * coalesced into one
+ * see arch/arc/kernel/smp.c: ipi_send_msg_one()
+ */
+ __mcip_cmd(CMD_INTRPT_READ_STATUS, cpu);
+ ipi_was_pending = read_aux_reg(ARC_REG_MCIP_READBACK);
+ if (!ipi_was_pending)
+ __mcip_cmd(CMD_INTRPT_GENERATE_IRQ, cpu);
+
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void mcip_ipi_clear(int irq)
+{
+ unsigned int cpu, c;
+ unsigned long flags;
+
+ if (unlikely(irq == SOFTIRQ_IRQ)) {
+ arc_softirq_clear(irq);
+ return;
+ }
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+
+ /* Who sent the IPI */
+ __mcip_cmd(CMD_INTRPT_CHECK_SOURCE, 0);
+
+ cpu = read_aux_reg(ARC_REG_MCIP_READBACK); /* 1,2,4,8... */
+
+ /*
+ * In rare case, multiple concurrent IPIs sent to same target can
+ * possibly be coalesced by MCIP into 1 asserted IRQ, so @cpus can be
+ * "vectored" (multiple bits sets) as opposed to typical single bit
+ */
+ do {
+ c = __ffs(cpu); /* 0,1,2,3 */
+ __mcip_cmd(CMD_INTRPT_GENERATE_ACK, c);
+ cpu &= ~(1U << c);
+ } while (cpu);
+
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void mcip_probe_n_setup(void)
+{
+ struct mcip_bcr mp;
+
+ READ_BCR(ARC_REG_MCIP_BCR, mp);
+
+ sprintf(smp_cpuinfo_buf,
+ "Extn [SMP]\t: ARConnect (v%d): %d cores with %s%s%s%s\n",
+ mp.ver, mp.num_cores,
+ IS_AVAIL1(mp.ipi, "IPI "),
+ IS_AVAIL1(mp.idu, "IDU "),
+ IS_AVAIL1(mp.dbg, "DEBUG "),
+ IS_AVAIL1(mp.gfrc, "GFRC"));
+
+ cpuinfo_arc700[0].extn.gfrc = mp.gfrc;
+}
+
+struct plat_smp_ops plat_smp_ops = {
+ .info = smp_cpuinfo_buf,
+ .init_early_smp = mcip_probe_n_setup,
+ .init_per_cpu = mcip_setup_per_cpu,
+ .ipi_send = mcip_ipi_send,
+ .ipi_clear = mcip_ipi_clear,
+};
+
+#endif
+
+/***************************************************************************
+ * ARCv2 Interrupt Distribution Unit (IDU)
+ *
+ * Connects external "COMMON" IRQs to core intc, providing:
+ * -dynamic routing (IRQ affinity)
+ * -load balancing (Round Robin interrupt distribution)
+ * -1:N distribution
+ *
+ * It physically resides in the MCIP hw block
+ */
+
+#include <linux/irqchip.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+
+/*
+ * Set the DEST for @cmn_irq to @cpu_mask (1 bit per core)
+ */
+static void idu_set_dest(unsigned int cmn_irq, unsigned int cpu_mask)
+{
+ __mcip_cmd_data(CMD_IDU_SET_DEST, cmn_irq, cpu_mask);
+}
+
+static void idu_set_mode(unsigned int cmn_irq, bool set_lvl, unsigned int lvl,
+ bool set_distr, unsigned int distr)
+{
+ union {
+ unsigned int word;
+ struct {
+ unsigned int distr:2, pad:2, lvl:1, pad2:27;
+ };
+ } data;
+
+ data.word = __mcip_cmd_read(CMD_IDU_READ_MODE, cmn_irq);
+ if (set_distr)
+ data.distr = distr;
+ if (set_lvl)
+ data.lvl = lvl;
+ __mcip_cmd_data(CMD_IDU_SET_MODE, cmn_irq, data.word);
+}
+
+static void idu_irq_mask_raw(irq_hw_number_t hwirq)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+ __mcip_cmd_data(CMD_IDU_SET_MASK, hwirq, 1);
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void idu_irq_mask(struct irq_data *data)
+{
+ idu_irq_mask_raw(data->hwirq);
+}
+
+static void idu_irq_unmask(struct irq_data *data)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+ __mcip_cmd_data(CMD_IDU_SET_MASK, data->hwirq, 0);
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void idu_irq_ack(struct irq_data *data)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+ __mcip_cmd(CMD_IDU_ACK_CIRQ, data->hwirq);
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void idu_irq_mask_ack(struct irq_data *data)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+ __mcip_cmd_data(CMD_IDU_SET_MASK, data->hwirq, 1);
+ __mcip_cmd(CMD_IDU_ACK_CIRQ, data->hwirq);
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static int
+idu_irq_set_affinity(struct irq_data *data, const struct cpumask *cpumask,
+ bool force)
+{
+ unsigned long flags;
+ cpumask_t online;
+ unsigned int destination_bits;
+ unsigned int distribution_mode;
+
+ /* errout if no online cpu per @cpumask */
+ if (!cpumask_and(&online, cpumask, cpu_online_mask))
+ return -EINVAL;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+
+ destination_bits = cpumask_bits(&online)[0];
+ idu_set_dest(data->hwirq, destination_bits);
+
+ if (ffs(destination_bits) == fls(destination_bits))
+ distribution_mode = IDU_M_DISTRI_DEST;
+ else
+ distribution_mode = IDU_M_DISTRI_RR;
+
+ idu_set_mode(data->hwirq, false, 0, true, distribution_mode);
+
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+
+ return IRQ_SET_MASK_OK;
+}
+
+static int idu_irq_set_type(struct irq_data *data, u32 type)
+{
+ unsigned long flags;
+
+ /*
+ * ARCv2 IDU HW does not support inverse polarity, so these are the
+ * only interrupt types supported.
+ */
+ if (type & ~(IRQ_TYPE_EDGE_RISING | IRQ_TYPE_LEVEL_HIGH))
+ return -EINVAL;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+
+ idu_set_mode(data->hwirq, true,
+ type & IRQ_TYPE_EDGE_RISING ? IDU_M_TRIG_EDGE :
+ IDU_M_TRIG_LEVEL,
+ false, 0);
+
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+
+ return 0;
+}
+
+static void idu_irq_enable(struct irq_data *data)
+{
+ /*
+ * By default send all common interrupts to all available online CPUs.
+ * The affinity of common interrupts in IDU must be set manually since
+ * in some cases the kernel will not call irq_set_affinity() by itself:
+ * 1. When the kernel is not configured with support of SMP.
+ * 2. When the kernel is configured with support of SMP but upper
+ * interrupt controllers does not support setting of the affinity
+ * and cannot propagate it to IDU.
+ */
+ idu_irq_set_affinity(data, cpu_online_mask, false);
+ idu_irq_unmask(data);
+}
+
+static struct irq_chip idu_irq_chip = {
+ .name = "MCIP IDU Intc",
+ .irq_mask = idu_irq_mask,
+ .irq_unmask = idu_irq_unmask,
+ .irq_ack = idu_irq_ack,
+ .irq_mask_ack = idu_irq_mask_ack,
+ .irq_enable = idu_irq_enable,
+ .irq_set_type = idu_irq_set_type,
+#ifdef CONFIG_SMP
+ .irq_set_affinity = idu_irq_set_affinity,
+#endif
+
+};
+
+static void idu_cascade_isr(struct irq_desc *desc)
+{
+ struct irq_domain *idu_domain = irq_desc_get_handler_data(desc);
+ struct irq_chip *core_chip = irq_desc_get_chip(desc);
+ irq_hw_number_t core_hwirq = irqd_to_hwirq(irq_desc_get_irq_data(desc));
+ irq_hw_number_t idu_hwirq = core_hwirq - FIRST_EXT_IRQ;
+
+ chained_irq_enter(core_chip, desc);
+ generic_handle_domain_irq(idu_domain, idu_hwirq);
+ chained_irq_exit(core_chip, desc);
+}
+
+static int idu_irq_map(struct irq_domain *d, unsigned int virq, irq_hw_number_t hwirq)
+{
+ irq_set_chip_and_handler(virq, &idu_irq_chip, handle_level_irq);
+ irq_set_status_flags(virq, IRQ_MOVE_PCNTXT);
+
+ return 0;
+}
+
+static const struct irq_domain_ops idu_irq_ops = {
+ .xlate = irq_domain_xlate_onetwocell,
+ .map = idu_irq_map,
+};
+
+/*
+ * [16, 23]: Statically assigned always private-per-core (Timers, WDT, IPI)
+ * [24, 23+C]: If C > 0 then "C" common IRQs
+ * [24+C, N]: Not statically assigned, private-per-core
+ */
+
+
+static int __init
+idu_of_init(struct device_node *intc, struct device_node *parent)
+{
+ struct irq_domain *domain;
+ int nr_irqs;
+ int i, virq;
+ struct mcip_bcr mp;
+ struct mcip_idu_bcr idu_bcr;
+
+ READ_BCR(ARC_REG_MCIP_BCR, mp);
+
+ if (!mp.idu)
+ panic("IDU not detected, but DeviceTree using it");
+
+ READ_BCR(ARC_REG_MCIP_IDU_BCR, idu_bcr);
+ nr_irqs = mcip_idu_bcr_to_nr_irqs(idu_bcr);
+
+ pr_info("MCIP: IDU supports %u common irqs\n", nr_irqs);
+
+ domain = irq_domain_add_linear(intc, nr_irqs, &idu_irq_ops, NULL);
+
+ /* Parent interrupts (core-intc) are already mapped */
+
+ for (i = 0; i < nr_irqs; i++) {
+ /* Mask all common interrupts by default */
+ idu_irq_mask_raw(i);
+
+ /*
+ * Return parent uplink IRQs (towards core intc) 24,25,.....
+ * this step has been done before already
+ * however we need it to get the parent virq and set IDU handler
+ * as first level isr
+ */
+ virq = irq_create_mapping(NULL, i + FIRST_EXT_IRQ);
+ BUG_ON(!virq);
+ irq_set_chained_handler_and_data(virq, idu_cascade_isr, domain);
+ }
+
+ __mcip_cmd(CMD_IDU_ENABLE, 0);
+
+ return 0;
+}
+IRQCHIP_DECLARE(arcv2_idu_intc, "snps,archs-idu-intc", idu_of_init);