aboutsummaryrefslogtreecommitdiff
path: root/drivers/pci/controller/pcie-iproc-msi.c
diff options
context:
space:
mode:
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/pci/controller/pcie-iproc-msi.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/pci/controller/pcie-iproc-msi.c')
-rw-r--r--drivers/pci/controller/pcie-iproc-msi.c682
1 files changed, 682 insertions, 0 deletions
diff --git a/drivers/pci/controller/pcie-iproc-msi.c b/drivers/pci/controller/pcie-iproc-msi.c
new file mode 100644
index 000000000..fee036b07
--- /dev/null
+++ b/drivers/pci/controller/pcie-iproc-msi.c
@@ -0,0 +1,682 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015 Broadcom Corporation
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/msi.h>
+#include <linux/of_irq.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+
+#include "pcie-iproc.h"
+
+#define IPROC_MSI_INTR_EN_SHIFT 11
+#define IPROC_MSI_INTR_EN BIT(IPROC_MSI_INTR_EN_SHIFT)
+#define IPROC_MSI_INT_N_EVENT_SHIFT 1
+#define IPROC_MSI_INT_N_EVENT BIT(IPROC_MSI_INT_N_EVENT_SHIFT)
+#define IPROC_MSI_EQ_EN_SHIFT 0
+#define IPROC_MSI_EQ_EN BIT(IPROC_MSI_EQ_EN_SHIFT)
+
+#define IPROC_MSI_EQ_MASK 0x3f
+
+/* Max number of GIC interrupts */
+#define NR_HW_IRQS 6
+
+/* Number of entries in each event queue */
+#define EQ_LEN 64
+
+/* Size of each event queue memory region */
+#define EQ_MEM_REGION_SIZE SZ_4K
+
+/* Size of each MSI address region */
+#define MSI_MEM_REGION_SIZE SZ_4K
+
+enum iproc_msi_reg {
+ IPROC_MSI_EQ_PAGE = 0,
+ IPROC_MSI_EQ_PAGE_UPPER,
+ IPROC_MSI_PAGE,
+ IPROC_MSI_PAGE_UPPER,
+ IPROC_MSI_CTRL,
+ IPROC_MSI_EQ_HEAD,
+ IPROC_MSI_EQ_TAIL,
+ IPROC_MSI_INTS_EN,
+ IPROC_MSI_REG_SIZE,
+};
+
+struct iproc_msi;
+
+/**
+ * struct iproc_msi_grp - iProc MSI group
+ *
+ * One MSI group is allocated per GIC interrupt, serviced by one iProc MSI
+ * event queue.
+ *
+ * @msi: pointer to iProc MSI data
+ * @gic_irq: GIC interrupt
+ * @eq: Event queue number
+ */
+struct iproc_msi_grp {
+ struct iproc_msi *msi;
+ int gic_irq;
+ unsigned int eq;
+};
+
+/**
+ * struct iproc_msi - iProc event queue based MSI
+ *
+ * Only meant to be used on platforms without MSI support integrated into the
+ * GIC.
+ *
+ * @pcie: pointer to iProc PCIe data
+ * @reg_offsets: MSI register offsets
+ * @grps: MSI groups
+ * @nr_irqs: number of total interrupts connected to GIC
+ * @nr_cpus: number of toal CPUs
+ * @has_inten_reg: indicates the MSI interrupt enable register needs to be
+ * set explicitly (required for some legacy platforms)
+ * @bitmap: MSI vector bitmap
+ * @bitmap_lock: lock to protect access to the MSI bitmap
+ * @nr_msi_vecs: total number of MSI vectors
+ * @inner_domain: inner IRQ domain
+ * @msi_domain: MSI IRQ domain
+ * @nr_eq_region: required number of 4K aligned memory region for MSI event
+ * queues
+ * @nr_msi_region: required number of 4K aligned address region for MSI posted
+ * writes
+ * @eq_cpu: pointer to allocated memory region for MSI event queues
+ * @eq_dma: DMA address of MSI event queues
+ * @msi_addr: MSI address
+ */
+struct iproc_msi {
+ struct iproc_pcie *pcie;
+ const u16 (*reg_offsets)[IPROC_MSI_REG_SIZE];
+ struct iproc_msi_grp *grps;
+ int nr_irqs;
+ int nr_cpus;
+ bool has_inten_reg;
+ unsigned long *bitmap;
+ struct mutex bitmap_lock;
+ unsigned int nr_msi_vecs;
+ struct irq_domain *inner_domain;
+ struct irq_domain *msi_domain;
+ unsigned int nr_eq_region;
+ unsigned int nr_msi_region;
+ void *eq_cpu;
+ dma_addr_t eq_dma;
+ phys_addr_t msi_addr;
+};
+
+static const u16 iproc_msi_reg_paxb[NR_HW_IRQS][IPROC_MSI_REG_SIZE] = {
+ { 0x200, 0x2c0, 0x204, 0x2c4, 0x210, 0x250, 0x254, 0x208 },
+ { 0x200, 0x2c0, 0x204, 0x2c4, 0x214, 0x258, 0x25c, 0x208 },
+ { 0x200, 0x2c0, 0x204, 0x2c4, 0x218, 0x260, 0x264, 0x208 },
+ { 0x200, 0x2c0, 0x204, 0x2c4, 0x21c, 0x268, 0x26c, 0x208 },
+ { 0x200, 0x2c0, 0x204, 0x2c4, 0x220, 0x270, 0x274, 0x208 },
+ { 0x200, 0x2c0, 0x204, 0x2c4, 0x224, 0x278, 0x27c, 0x208 },
+};
+
+static const u16 iproc_msi_reg_paxc[NR_HW_IRQS][IPROC_MSI_REG_SIZE] = {
+ { 0xc00, 0xc04, 0xc08, 0xc0c, 0xc40, 0xc50, 0xc60 },
+ { 0xc10, 0xc14, 0xc18, 0xc1c, 0xc44, 0xc54, 0xc64 },
+ { 0xc20, 0xc24, 0xc28, 0xc2c, 0xc48, 0xc58, 0xc68 },
+ { 0xc30, 0xc34, 0xc38, 0xc3c, 0xc4c, 0xc5c, 0xc6c },
+};
+
+static inline u32 iproc_msi_read_reg(struct iproc_msi *msi,
+ enum iproc_msi_reg reg,
+ unsigned int eq)
+{
+ struct iproc_pcie *pcie = msi->pcie;
+
+ return readl_relaxed(pcie->base + msi->reg_offsets[eq][reg]);
+}
+
+static inline void iproc_msi_write_reg(struct iproc_msi *msi,
+ enum iproc_msi_reg reg,
+ int eq, u32 val)
+{
+ struct iproc_pcie *pcie = msi->pcie;
+
+ writel_relaxed(val, pcie->base + msi->reg_offsets[eq][reg]);
+}
+
+static inline u32 hwirq_to_group(struct iproc_msi *msi, unsigned long hwirq)
+{
+ return (hwirq % msi->nr_irqs);
+}
+
+static inline unsigned int iproc_msi_addr_offset(struct iproc_msi *msi,
+ unsigned long hwirq)
+{
+ if (msi->nr_msi_region > 1)
+ return hwirq_to_group(msi, hwirq) * MSI_MEM_REGION_SIZE;
+ else
+ return hwirq_to_group(msi, hwirq) * sizeof(u32);
+}
+
+static inline unsigned int iproc_msi_eq_offset(struct iproc_msi *msi, u32 eq)
+{
+ if (msi->nr_eq_region > 1)
+ return eq * EQ_MEM_REGION_SIZE;
+ else
+ return eq * EQ_LEN * sizeof(u32);
+}
+
+static struct irq_chip iproc_msi_irq_chip = {
+ .name = "iProc-MSI",
+};
+
+static struct msi_domain_info iproc_msi_domain_info = {
+ .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+ MSI_FLAG_PCI_MSIX,
+ .chip = &iproc_msi_irq_chip,
+};
+
+/*
+ * In iProc PCIe core, each MSI group is serviced by a GIC interrupt and a
+ * dedicated event queue. Each MSI group can support up to 64 MSI vectors.
+ *
+ * The number of MSI groups varies between different iProc SoCs. The total
+ * number of CPU cores also varies. To support MSI IRQ affinity, we
+ * distribute GIC interrupts across all available CPUs. MSI vector is moved
+ * from one GIC interrupt to another to steer to the target CPU.
+ *
+ * Assuming:
+ * - the number of MSI groups is M
+ * - the number of CPU cores is N
+ * - M is always a multiple of N
+ *
+ * Total number of raw MSI vectors = M * 64
+ * Total number of supported MSI vectors = (M * 64) / N
+ */
+static inline int hwirq_to_cpu(struct iproc_msi *msi, unsigned long hwirq)
+{
+ return (hwirq % msi->nr_cpus);
+}
+
+static inline unsigned long hwirq_to_canonical_hwirq(struct iproc_msi *msi,
+ unsigned long hwirq)
+{
+ return (hwirq - hwirq_to_cpu(msi, hwirq));
+}
+
+static int iproc_msi_irq_set_affinity(struct irq_data *data,
+ const struct cpumask *mask, bool force)
+{
+ struct iproc_msi *msi = irq_data_get_irq_chip_data(data);
+ int target_cpu = cpumask_first(mask);
+ int curr_cpu;
+ int ret;
+
+ curr_cpu = hwirq_to_cpu(msi, data->hwirq);
+ if (curr_cpu == target_cpu)
+ ret = IRQ_SET_MASK_OK_DONE;
+ else {
+ /* steer MSI to the target CPU */
+ data->hwirq = hwirq_to_canonical_hwirq(msi, data->hwirq) + target_cpu;
+ ret = IRQ_SET_MASK_OK;
+ }
+
+ irq_data_update_effective_affinity(data, cpumask_of(target_cpu));
+
+ return ret;
+}
+
+static void iproc_msi_irq_compose_msi_msg(struct irq_data *data,
+ struct msi_msg *msg)
+{
+ struct iproc_msi *msi = irq_data_get_irq_chip_data(data);
+ dma_addr_t addr;
+
+ addr = msi->msi_addr + iproc_msi_addr_offset(msi, data->hwirq);
+ msg->address_lo = lower_32_bits(addr);
+ msg->address_hi = upper_32_bits(addr);
+ msg->data = data->hwirq << 5;
+}
+
+static struct irq_chip iproc_msi_bottom_irq_chip = {
+ .name = "MSI",
+ .irq_set_affinity = iproc_msi_irq_set_affinity,
+ .irq_compose_msi_msg = iproc_msi_irq_compose_msi_msg,
+};
+
+static int iproc_msi_irq_domain_alloc(struct irq_domain *domain,
+ unsigned int virq, unsigned int nr_irqs,
+ void *args)
+{
+ struct iproc_msi *msi = domain->host_data;
+ int hwirq, i;
+
+ if (msi->nr_cpus > 1 && nr_irqs > 1)
+ return -EINVAL;
+
+ mutex_lock(&msi->bitmap_lock);
+
+ /*
+ * Allocate 'nr_irqs' multiplied by 'nr_cpus' number of MSI vectors
+ * each time
+ */
+ hwirq = bitmap_find_free_region(msi->bitmap, msi->nr_msi_vecs,
+ order_base_2(msi->nr_cpus * nr_irqs));
+
+ mutex_unlock(&msi->bitmap_lock);
+
+ if (hwirq < 0)
+ return -ENOSPC;
+
+ for (i = 0; i < nr_irqs; i++) {
+ irq_domain_set_info(domain, virq + i, hwirq + i,
+ &iproc_msi_bottom_irq_chip,
+ domain->host_data, handle_simple_irq,
+ NULL, NULL);
+ }
+
+ return 0;
+}
+
+static void iproc_msi_irq_domain_free(struct irq_domain *domain,
+ unsigned int virq, unsigned int nr_irqs)
+{
+ struct irq_data *data = irq_domain_get_irq_data(domain, virq);
+ struct iproc_msi *msi = irq_data_get_irq_chip_data(data);
+ unsigned int hwirq;
+
+ mutex_lock(&msi->bitmap_lock);
+
+ hwirq = hwirq_to_canonical_hwirq(msi, data->hwirq);
+ bitmap_release_region(msi->bitmap, hwirq,
+ order_base_2(msi->nr_cpus * nr_irqs));
+
+ mutex_unlock(&msi->bitmap_lock);
+
+ irq_domain_free_irqs_parent(domain, virq, nr_irqs);
+}
+
+static const struct irq_domain_ops msi_domain_ops = {
+ .alloc = iproc_msi_irq_domain_alloc,
+ .free = iproc_msi_irq_domain_free,
+};
+
+static inline u32 decode_msi_hwirq(struct iproc_msi *msi, u32 eq, u32 head)
+{
+ u32 __iomem *msg;
+ u32 hwirq;
+ unsigned int offs;
+
+ offs = iproc_msi_eq_offset(msi, eq) + head * sizeof(u32);
+ msg = (u32 __iomem *)(msi->eq_cpu + offs);
+ hwirq = readl(msg);
+ hwirq = (hwirq >> 5) + (hwirq & 0x1f);
+
+ /*
+ * Since we have multiple hwirq mapped to a single MSI vector,
+ * now we need to derive the hwirq at CPU0. It can then be used to
+ * mapped back to virq.
+ */
+ return hwirq_to_canonical_hwirq(msi, hwirq);
+}
+
+static void iproc_msi_handler(struct irq_desc *desc)
+{
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ struct iproc_msi_grp *grp;
+ struct iproc_msi *msi;
+ u32 eq, head, tail, nr_events;
+ unsigned long hwirq;
+
+ chained_irq_enter(chip, desc);
+
+ grp = irq_desc_get_handler_data(desc);
+ msi = grp->msi;
+ eq = grp->eq;
+
+ /*
+ * iProc MSI event queue is tracked by head and tail pointers. Head
+ * pointer indicates the next entry (MSI data) to be consumed by SW in
+ * the queue and needs to be updated by SW. iProc MSI core uses the
+ * tail pointer as the next data insertion point.
+ *
+ * Entries between head and tail pointers contain valid MSI data. MSI
+ * data is guaranteed to be in the event queue memory before the tail
+ * pointer is updated by the iProc MSI core.
+ */
+ head = iproc_msi_read_reg(msi, IPROC_MSI_EQ_HEAD,
+ eq) & IPROC_MSI_EQ_MASK;
+ do {
+ tail = iproc_msi_read_reg(msi, IPROC_MSI_EQ_TAIL,
+ eq) & IPROC_MSI_EQ_MASK;
+
+ /*
+ * Figure out total number of events (MSI data) to be
+ * processed.
+ */
+ nr_events = (tail < head) ?
+ (EQ_LEN - (head - tail)) : (tail - head);
+ if (!nr_events)
+ break;
+
+ /* process all outstanding events */
+ while (nr_events--) {
+ hwirq = decode_msi_hwirq(msi, eq, head);
+ generic_handle_domain_irq(msi->inner_domain, hwirq);
+
+ head++;
+ head %= EQ_LEN;
+ }
+
+ /*
+ * Now all outstanding events have been processed. Update the
+ * head pointer.
+ */
+ iproc_msi_write_reg(msi, IPROC_MSI_EQ_HEAD, eq, head);
+
+ /*
+ * Now go read the tail pointer again to see if there are new
+ * outstanding events that came in during the above window.
+ */
+ } while (true);
+
+ chained_irq_exit(chip, desc);
+}
+
+static void iproc_msi_enable(struct iproc_msi *msi)
+{
+ int i, eq;
+ u32 val;
+
+ /* Program memory region for each event queue */
+ for (i = 0; i < msi->nr_eq_region; i++) {
+ dma_addr_t addr = msi->eq_dma + (i * EQ_MEM_REGION_SIZE);
+
+ iproc_msi_write_reg(msi, IPROC_MSI_EQ_PAGE, i,
+ lower_32_bits(addr));
+ iproc_msi_write_reg(msi, IPROC_MSI_EQ_PAGE_UPPER, i,
+ upper_32_bits(addr));
+ }
+
+ /* Program address region for MSI posted writes */
+ for (i = 0; i < msi->nr_msi_region; i++) {
+ phys_addr_t addr = msi->msi_addr + (i * MSI_MEM_REGION_SIZE);
+
+ iproc_msi_write_reg(msi, IPROC_MSI_PAGE, i,
+ lower_32_bits(addr));
+ iproc_msi_write_reg(msi, IPROC_MSI_PAGE_UPPER, i,
+ upper_32_bits(addr));
+ }
+
+ for (eq = 0; eq < msi->nr_irqs; eq++) {
+ /* Enable MSI event queue */
+ val = IPROC_MSI_INTR_EN | IPROC_MSI_INT_N_EVENT |
+ IPROC_MSI_EQ_EN;
+ iproc_msi_write_reg(msi, IPROC_MSI_CTRL, eq, val);
+
+ /*
+ * Some legacy platforms require the MSI interrupt enable
+ * register to be set explicitly.
+ */
+ if (msi->has_inten_reg) {
+ val = iproc_msi_read_reg(msi, IPROC_MSI_INTS_EN, eq);
+ val |= BIT(eq);
+ iproc_msi_write_reg(msi, IPROC_MSI_INTS_EN, eq, val);
+ }
+ }
+}
+
+static void iproc_msi_disable(struct iproc_msi *msi)
+{
+ u32 eq, val;
+
+ for (eq = 0; eq < msi->nr_irqs; eq++) {
+ if (msi->has_inten_reg) {
+ val = iproc_msi_read_reg(msi, IPROC_MSI_INTS_EN, eq);
+ val &= ~BIT(eq);
+ iproc_msi_write_reg(msi, IPROC_MSI_INTS_EN, eq, val);
+ }
+
+ val = iproc_msi_read_reg(msi, IPROC_MSI_CTRL, eq);
+ val &= ~(IPROC_MSI_INTR_EN | IPROC_MSI_INT_N_EVENT |
+ IPROC_MSI_EQ_EN);
+ iproc_msi_write_reg(msi, IPROC_MSI_CTRL, eq, val);
+ }
+}
+
+static int iproc_msi_alloc_domains(struct device_node *node,
+ struct iproc_msi *msi)
+{
+ msi->inner_domain = irq_domain_add_linear(NULL, msi->nr_msi_vecs,
+ &msi_domain_ops, msi);
+ if (!msi->inner_domain)
+ return -ENOMEM;
+
+ msi->msi_domain = pci_msi_create_irq_domain(of_node_to_fwnode(node),
+ &iproc_msi_domain_info,
+ msi->inner_domain);
+ if (!msi->msi_domain) {
+ irq_domain_remove(msi->inner_domain);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void iproc_msi_free_domains(struct iproc_msi *msi)
+{
+ if (msi->msi_domain)
+ irq_domain_remove(msi->msi_domain);
+
+ if (msi->inner_domain)
+ irq_domain_remove(msi->inner_domain);
+}
+
+static void iproc_msi_irq_free(struct iproc_msi *msi, unsigned int cpu)
+{
+ int i;
+
+ for (i = cpu; i < msi->nr_irqs; i += msi->nr_cpus) {
+ irq_set_chained_handler_and_data(msi->grps[i].gic_irq,
+ NULL, NULL);
+ }
+}
+
+static int iproc_msi_irq_setup(struct iproc_msi *msi, unsigned int cpu)
+{
+ int i, ret;
+ cpumask_var_t mask;
+ struct iproc_pcie *pcie = msi->pcie;
+
+ for (i = cpu; i < msi->nr_irqs; i += msi->nr_cpus) {
+ irq_set_chained_handler_and_data(msi->grps[i].gic_irq,
+ iproc_msi_handler,
+ &msi->grps[i]);
+ /* Dedicate GIC interrupt to each CPU core */
+ if (alloc_cpumask_var(&mask, GFP_KERNEL)) {
+ cpumask_clear(mask);
+ cpumask_set_cpu(cpu, mask);
+ ret = irq_set_affinity(msi->grps[i].gic_irq, mask);
+ if (ret)
+ dev_err(pcie->dev,
+ "failed to set affinity for IRQ%d\n",
+ msi->grps[i].gic_irq);
+ free_cpumask_var(mask);
+ } else {
+ dev_err(pcie->dev, "failed to alloc CPU mask\n");
+ ret = -EINVAL;
+ }
+
+ if (ret) {
+ /* Free all configured/unconfigured IRQs */
+ iproc_msi_irq_free(msi, cpu);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+int iproc_msi_init(struct iproc_pcie *pcie, struct device_node *node)
+{
+ struct iproc_msi *msi;
+ int i, ret;
+ unsigned int cpu;
+
+ if (!of_device_is_compatible(node, "brcm,iproc-msi"))
+ return -ENODEV;
+
+ if (!of_find_property(node, "msi-controller", NULL))
+ return -ENODEV;
+
+ if (pcie->msi)
+ return -EBUSY;
+
+ msi = devm_kzalloc(pcie->dev, sizeof(*msi), GFP_KERNEL);
+ if (!msi)
+ return -ENOMEM;
+
+ msi->pcie = pcie;
+ pcie->msi = msi;
+ msi->msi_addr = pcie->base_addr;
+ mutex_init(&msi->bitmap_lock);
+ msi->nr_cpus = num_possible_cpus();
+
+ if (msi->nr_cpus == 1)
+ iproc_msi_domain_info.flags |= MSI_FLAG_MULTI_PCI_MSI;
+
+ msi->nr_irqs = of_irq_count(node);
+ if (!msi->nr_irqs) {
+ dev_err(pcie->dev, "found no MSI GIC interrupt\n");
+ return -ENODEV;
+ }
+
+ if (msi->nr_irqs > NR_HW_IRQS) {
+ dev_warn(pcie->dev, "too many MSI GIC interrupts defined %d\n",
+ msi->nr_irqs);
+ msi->nr_irqs = NR_HW_IRQS;
+ }
+
+ if (msi->nr_irqs < msi->nr_cpus) {
+ dev_err(pcie->dev,
+ "not enough GIC interrupts for MSI affinity\n");
+ return -EINVAL;
+ }
+
+ if (msi->nr_irqs % msi->nr_cpus != 0) {
+ msi->nr_irqs -= msi->nr_irqs % msi->nr_cpus;
+ dev_warn(pcie->dev, "Reducing number of interrupts to %d\n",
+ msi->nr_irqs);
+ }
+
+ switch (pcie->type) {
+ case IPROC_PCIE_PAXB_BCMA:
+ case IPROC_PCIE_PAXB:
+ msi->reg_offsets = iproc_msi_reg_paxb;
+ msi->nr_eq_region = 1;
+ msi->nr_msi_region = 1;
+ break;
+ case IPROC_PCIE_PAXC:
+ msi->reg_offsets = iproc_msi_reg_paxc;
+ msi->nr_eq_region = msi->nr_irqs;
+ msi->nr_msi_region = msi->nr_irqs;
+ break;
+ default:
+ dev_err(pcie->dev, "incompatible iProc PCIe interface\n");
+ return -EINVAL;
+ }
+
+ if (of_find_property(node, "brcm,pcie-msi-inten", NULL))
+ msi->has_inten_reg = true;
+
+ msi->nr_msi_vecs = msi->nr_irqs * EQ_LEN;
+ msi->bitmap = devm_bitmap_zalloc(pcie->dev, msi->nr_msi_vecs,
+ GFP_KERNEL);
+ if (!msi->bitmap)
+ return -ENOMEM;
+
+ msi->grps = devm_kcalloc(pcie->dev, msi->nr_irqs, sizeof(*msi->grps),
+ GFP_KERNEL);
+ if (!msi->grps)
+ return -ENOMEM;
+
+ for (i = 0; i < msi->nr_irqs; i++) {
+ unsigned int irq = irq_of_parse_and_map(node, i);
+
+ if (!irq) {
+ dev_err(pcie->dev, "unable to parse/map interrupt\n");
+ ret = -ENODEV;
+ goto free_irqs;
+ }
+ msi->grps[i].gic_irq = irq;
+ msi->grps[i].msi = msi;
+ msi->grps[i].eq = i;
+ }
+
+ /* Reserve memory for event queue and make sure memories are zeroed */
+ msi->eq_cpu = dma_alloc_coherent(pcie->dev,
+ msi->nr_eq_region * EQ_MEM_REGION_SIZE,
+ &msi->eq_dma, GFP_KERNEL);
+ if (!msi->eq_cpu) {
+ ret = -ENOMEM;
+ goto free_irqs;
+ }
+
+ ret = iproc_msi_alloc_domains(node, msi);
+ if (ret) {
+ dev_err(pcie->dev, "failed to create MSI domains\n");
+ goto free_eq_dma;
+ }
+
+ for_each_online_cpu(cpu) {
+ ret = iproc_msi_irq_setup(msi, cpu);
+ if (ret)
+ goto free_msi_irq;
+ }
+
+ iproc_msi_enable(msi);
+
+ return 0;
+
+free_msi_irq:
+ for_each_online_cpu(cpu)
+ iproc_msi_irq_free(msi, cpu);
+ iproc_msi_free_domains(msi);
+
+free_eq_dma:
+ dma_free_coherent(pcie->dev, msi->nr_eq_region * EQ_MEM_REGION_SIZE,
+ msi->eq_cpu, msi->eq_dma);
+
+free_irqs:
+ for (i = 0; i < msi->nr_irqs; i++) {
+ if (msi->grps[i].gic_irq)
+ irq_dispose_mapping(msi->grps[i].gic_irq);
+ }
+ pcie->msi = NULL;
+ return ret;
+}
+EXPORT_SYMBOL(iproc_msi_init);
+
+void iproc_msi_exit(struct iproc_pcie *pcie)
+{
+ struct iproc_msi *msi = pcie->msi;
+ unsigned int i, cpu;
+
+ if (!msi)
+ return;
+
+ iproc_msi_disable(msi);
+
+ for_each_online_cpu(cpu)
+ iproc_msi_irq_free(msi, cpu);
+
+ iproc_msi_free_domains(msi);
+
+ dma_free_coherent(pcie->dev, msi->nr_eq_region * EQ_MEM_REGION_SIZE,
+ msi->eq_cpu, msi->eq_dma);
+
+ for (i = 0; i < msi->nr_irqs; i++) {
+ if (msi->grps[i].gic_irq)
+ irq_dispose_mapping(msi->grps[i].gic_irq);
+ }
+}
+EXPORT_SYMBOL(iproc_msi_exit);