diff options
author | 2023-02-21 18:24:12 -0800 | |
---|---|---|
committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/mips/kernel/smp-cps.c | |
download | linux-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 'arch/mips/kernel/smp-cps.c')
-rw-r--r-- | arch/mips/kernel/smp-cps.c | 644 |
1 files changed, 644 insertions, 0 deletions
diff --git a/arch/mips/kernel/smp-cps.c b/arch/mips/kernel/smp-cps.c new file mode 100644 index 000000000..bcd6a944b --- /dev/null +++ b/arch/mips/kernel/smp-cps.c @@ -0,0 +1,644 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2013 Imagination Technologies + * Author: Paul Burton <paul.burton@mips.com> + */ + +#include <linux/cpu.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/sched/task_stack.h> +#include <linux/sched/hotplug.h> +#include <linux/slab.h> +#include <linux/smp.h> +#include <linux/types.h> +#include <linux/irq.h> + +#include <asm/bcache.h> +#include <asm/mips-cps.h> +#include <asm/mips_mt.h> +#include <asm/mipsregs.h> +#include <asm/pm-cps.h> +#include <asm/r4kcache.h> +#include <asm/smp-cps.h> +#include <asm/time.h> +#include <asm/uasm.h> + +static bool threads_disabled; +static DECLARE_BITMAP(core_power, NR_CPUS); + +struct core_boot_config *mips_cps_core_bootcfg; + +static int __init setup_nothreads(char *s) +{ + threads_disabled = true; + return 0; +} +early_param("nothreads", setup_nothreads); + +static unsigned core_vpe_count(unsigned int cluster, unsigned core) +{ + if (threads_disabled) + return 1; + + return mips_cps_numvps(cluster, core); +} + +static void __init cps_smp_setup(void) +{ + unsigned int nclusters, ncores, nvpes, core_vpes; + unsigned long core_entry; + int cl, c, v; + + /* Detect & record VPE topology */ + nvpes = 0; + nclusters = mips_cps_numclusters(); + pr_info("%s topology ", cpu_has_mips_r6 ? "VP" : "VPE"); + for (cl = 0; cl < nclusters; cl++) { + if (cl > 0) + pr_cont(","); + pr_cont("{"); + + ncores = mips_cps_numcores(cl); + for (c = 0; c < ncores; c++) { + core_vpes = core_vpe_count(cl, c); + + if (c > 0) + pr_cont(","); + pr_cont("%u", core_vpes); + + /* Use the number of VPEs in cluster 0 core 0 for smp_num_siblings */ + if (!cl && !c) + smp_num_siblings = core_vpes; + + for (v = 0; v < min_t(int, core_vpes, NR_CPUS - nvpes); v++) { + cpu_set_cluster(&cpu_data[nvpes + v], cl); + cpu_set_core(&cpu_data[nvpes + v], c); + cpu_set_vpe_id(&cpu_data[nvpes + v], v); + } + + nvpes += core_vpes; + } + + pr_cont("}"); + } + pr_cont(" total %u\n", nvpes); + + /* Indicate present CPUs (CPU being synonymous with VPE) */ + for (v = 0; v < min_t(unsigned, nvpes, NR_CPUS); v++) { + set_cpu_possible(v, cpu_cluster(&cpu_data[v]) == 0); + set_cpu_present(v, cpu_cluster(&cpu_data[v]) == 0); + __cpu_number_map[v] = v; + __cpu_logical_map[v] = v; + } + + /* Set a coherent default CCA (CWB) */ + change_c0_config(CONF_CM_CMASK, 0x5); + + /* Core 0 is powered up (we're running on it) */ + bitmap_set(core_power, 0, 1); + + /* Initialise core 0 */ + mips_cps_core_init(); + + /* Make core 0 coherent with everything */ + write_gcr_cl_coherence(0xff); + + if (mips_cm_revision() >= CM_REV_CM3) { + core_entry = CKSEG1ADDR((unsigned long)mips_cps_core_entry); + write_gcr_bev_base(core_entry); + } + +#ifdef CONFIG_MIPS_MT_FPAFF + /* If we have an FPU, enroll ourselves in the FPU-full mask */ + if (cpu_has_fpu) + cpumask_set_cpu(0, &mt_fpu_cpumask); +#endif /* CONFIG_MIPS_MT_FPAFF */ +} + +static void __init cps_prepare_cpus(unsigned int max_cpus) +{ + unsigned ncores, core_vpes, c, cca; + bool cca_unsuitable, cores_limited; + u32 *entry_code; + + mips_mt_set_cpuoptions(); + + /* Detect whether the CCA is unsuited to multi-core SMP */ + cca = read_c0_config() & CONF_CM_CMASK; + switch (cca) { + case 0x4: /* CWBE */ + case 0x5: /* CWB */ + /* The CCA is coherent, multi-core is fine */ + cca_unsuitable = false; + break; + + default: + /* CCA is not coherent, multi-core is not usable */ + cca_unsuitable = true; + } + + /* Warn the user if the CCA prevents multi-core */ + cores_limited = false; + if (cca_unsuitable || cpu_has_dc_aliases) { + for_each_present_cpu(c) { + if (cpus_are_siblings(smp_processor_id(), c)) + continue; + + set_cpu_present(c, false); + cores_limited = true; + } + } + if (cores_limited) + pr_warn("Using only one core due to %s%s%s\n", + cca_unsuitable ? "unsuitable CCA" : "", + (cca_unsuitable && cpu_has_dc_aliases) ? " & " : "", + cpu_has_dc_aliases ? "dcache aliasing" : ""); + + /* + * Patch the start of mips_cps_core_entry to provide: + * + * s0 = kseg0 CCA + */ + entry_code = (u32 *)&mips_cps_core_entry; + uasm_i_addiu(&entry_code, 16, 0, cca); + blast_dcache_range((unsigned long)&mips_cps_core_entry, + (unsigned long)entry_code); + bc_wback_inv((unsigned long)&mips_cps_core_entry, + (void *)entry_code - (void *)&mips_cps_core_entry); + __sync(); + + /* Allocate core boot configuration structs */ + ncores = mips_cps_numcores(0); + mips_cps_core_bootcfg = kcalloc(ncores, sizeof(*mips_cps_core_bootcfg), + GFP_KERNEL); + if (!mips_cps_core_bootcfg) { + pr_err("Failed to allocate boot config for %u cores\n", ncores); + goto err_out; + } + + /* Allocate VPE boot configuration structs */ + for (c = 0; c < ncores; c++) { + core_vpes = core_vpe_count(0, c); + mips_cps_core_bootcfg[c].vpe_config = kcalloc(core_vpes, + sizeof(*mips_cps_core_bootcfg[c].vpe_config), + GFP_KERNEL); + if (!mips_cps_core_bootcfg[c].vpe_config) { + pr_err("Failed to allocate %u VPE boot configs\n", + core_vpes); + goto err_out; + } + } + + /* Mark this CPU as booted */ + atomic_set(&mips_cps_core_bootcfg[cpu_core(¤t_cpu_data)].vpe_mask, + 1 << cpu_vpe_id(¤t_cpu_data)); + + return; +err_out: + /* Clean up allocations */ + if (mips_cps_core_bootcfg) { + for (c = 0; c < ncores; c++) + kfree(mips_cps_core_bootcfg[c].vpe_config); + kfree(mips_cps_core_bootcfg); + mips_cps_core_bootcfg = NULL; + } + + /* Effectively disable SMP by declaring CPUs not present */ + for_each_possible_cpu(c) { + if (c == 0) + continue; + set_cpu_present(c, false); + } +} + +static void boot_core(unsigned int core, unsigned int vpe_id) +{ + u32 stat, seq_state; + unsigned timeout; + + /* Select the appropriate core */ + mips_cm_lock_other(0, core, 0, CM_GCR_Cx_OTHER_BLOCK_LOCAL); + + /* Set its reset vector */ + write_gcr_co_reset_base(CKSEG1ADDR((unsigned long)mips_cps_core_entry)); + + /* Ensure its coherency is disabled */ + write_gcr_co_coherence(0); + + /* Start it with the legacy memory map and exception base */ + write_gcr_co_reset_ext_base(CM_GCR_Cx_RESET_EXT_BASE_UEB); + + /* Ensure the core can access the GCRs */ + set_gcr_access(1 << core); + + if (mips_cpc_present()) { + /* Reset the core */ + mips_cpc_lock_other(core); + + if (mips_cm_revision() >= CM_REV_CM3) { + /* Run only the requested VP following the reset */ + write_cpc_co_vp_stop(0xf); + write_cpc_co_vp_run(1 << vpe_id); + + /* + * Ensure that the VP_RUN register is written before the + * core leaves reset. + */ + wmb(); + } + + write_cpc_co_cmd(CPC_Cx_CMD_RESET); + + timeout = 100; + while (true) { + stat = read_cpc_co_stat_conf(); + seq_state = stat & CPC_Cx_STAT_CONF_SEQSTATE; + seq_state >>= __ffs(CPC_Cx_STAT_CONF_SEQSTATE); + + /* U6 == coherent execution, ie. the core is up */ + if (seq_state == CPC_Cx_STAT_CONF_SEQSTATE_U6) + break; + + /* Delay a little while before we start warning */ + if (timeout) { + timeout--; + mdelay(10); + continue; + } + + pr_warn("Waiting for core %u to start... STAT_CONF=0x%x\n", + core, stat); + mdelay(1000); + } + + mips_cpc_unlock_other(); + } else { + /* Take the core out of reset */ + write_gcr_co_reset_release(0); + } + + mips_cm_unlock_other(); + + /* The core is now powered up */ + bitmap_set(core_power, core, 1); +} + +static void remote_vpe_boot(void *dummy) +{ + unsigned core = cpu_core(¤t_cpu_data); + struct core_boot_config *core_cfg = &mips_cps_core_bootcfg[core]; + + mips_cps_boot_vpes(core_cfg, cpu_vpe_id(¤t_cpu_data)); +} + +static int cps_boot_secondary(int cpu, struct task_struct *idle) +{ + unsigned core = cpu_core(&cpu_data[cpu]); + unsigned vpe_id = cpu_vpe_id(&cpu_data[cpu]); + struct core_boot_config *core_cfg = &mips_cps_core_bootcfg[core]; + struct vpe_boot_config *vpe_cfg = &core_cfg->vpe_config[vpe_id]; + unsigned long core_entry; + unsigned int remote; + int err; + + /* We don't yet support booting CPUs in other clusters */ + if (cpu_cluster(&cpu_data[cpu]) != cpu_cluster(&raw_current_cpu_data)) + return -ENOSYS; + + vpe_cfg->pc = (unsigned long)&smp_bootstrap; + vpe_cfg->sp = __KSTK_TOS(idle); + vpe_cfg->gp = (unsigned long)task_thread_info(idle); + + atomic_or(1 << cpu_vpe_id(&cpu_data[cpu]), &core_cfg->vpe_mask); + + preempt_disable(); + + if (!test_bit(core, core_power)) { + /* Boot a VPE on a powered down core */ + boot_core(core, vpe_id); + goto out; + } + + if (cpu_has_vp) { + mips_cm_lock_other(0, core, vpe_id, CM_GCR_Cx_OTHER_BLOCK_LOCAL); + core_entry = CKSEG1ADDR((unsigned long)mips_cps_core_entry); + write_gcr_co_reset_base(core_entry); + mips_cm_unlock_other(); + } + + if (!cpus_are_siblings(cpu, smp_processor_id())) { + /* Boot a VPE on another powered up core */ + for (remote = 0; remote < NR_CPUS; remote++) { + if (!cpus_are_siblings(cpu, remote)) + continue; + if (cpu_online(remote)) + break; + } + if (remote >= NR_CPUS) { + pr_crit("No online CPU in core %u to start CPU%d\n", + core, cpu); + goto out; + } + + err = smp_call_function_single(remote, remote_vpe_boot, + NULL, 1); + if (err) + panic("Failed to call remote CPU\n"); + goto out; + } + + BUG_ON(!cpu_has_mipsmt && !cpu_has_vp); + + /* Boot a VPE on this core */ + mips_cps_boot_vpes(core_cfg, vpe_id); +out: + preempt_enable(); + return 0; +} + +static void cps_init_secondary(void) +{ + /* Disable MT - we only want to run 1 TC per VPE */ + if (cpu_has_mipsmt) + dmt(); + + if (mips_cm_revision() >= CM_REV_CM3) { + unsigned int ident = read_gic_vl_ident(); + + /* + * Ensure that our calculation of the VP ID matches up with + * what the GIC reports, otherwise we'll have configured + * interrupts incorrectly. + */ + BUG_ON(ident != mips_cm_vp_id(smp_processor_id())); + } + + if (cpu_has_veic) + clear_c0_status(ST0_IM); + else + change_c0_status(ST0_IM, STATUSF_IP2 | STATUSF_IP3 | + STATUSF_IP4 | STATUSF_IP5 | + STATUSF_IP6 | STATUSF_IP7); +} + +static void cps_smp_finish(void) +{ + write_c0_compare(read_c0_count() + (8 * mips_hpt_frequency / HZ)); + +#ifdef CONFIG_MIPS_MT_FPAFF + /* If we have an FPU, enroll ourselves in the FPU-full mask */ + if (cpu_has_fpu) + cpumask_set_cpu(smp_processor_id(), &mt_fpu_cpumask); +#endif /* CONFIG_MIPS_MT_FPAFF */ + + local_irq_enable(); +} + +#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_KEXEC) + +enum cpu_death { + CPU_DEATH_HALT, + CPU_DEATH_POWER, +}; + +static void cps_shutdown_this_cpu(enum cpu_death death) +{ + unsigned int cpu, core, vpe_id; + + cpu = smp_processor_id(); + core = cpu_core(&cpu_data[cpu]); + + if (death == CPU_DEATH_HALT) { + vpe_id = cpu_vpe_id(&cpu_data[cpu]); + + pr_debug("Halting core %d VP%d\n", core, vpe_id); + if (cpu_has_mipsmt) { + /* Halt this TC */ + write_c0_tchalt(TCHALT_H); + instruction_hazard(); + } else if (cpu_has_vp) { + write_cpc_cl_vp_stop(1 << vpe_id); + + /* Ensure that the VP_STOP register is written */ + wmb(); + } + } else { + pr_debug("Gating power to core %d\n", core); + /* Power down the core */ + cps_pm_enter_state(CPS_PM_POWER_GATED); + } +} + +#ifdef CONFIG_KEXEC + +static void cps_kexec_nonboot_cpu(void) +{ + if (cpu_has_mipsmt || cpu_has_vp) + cps_shutdown_this_cpu(CPU_DEATH_HALT); + else + cps_shutdown_this_cpu(CPU_DEATH_POWER); +} + +#endif /* CONFIG_KEXEC */ + +#endif /* CONFIG_HOTPLUG_CPU || CONFIG_KEXEC */ + +#ifdef CONFIG_HOTPLUG_CPU + +static int cps_cpu_disable(void) +{ + unsigned cpu = smp_processor_id(); + struct core_boot_config *core_cfg; + + if (!cps_pm_support_state(CPS_PM_POWER_GATED)) + return -EINVAL; + + core_cfg = &mips_cps_core_bootcfg[cpu_core(¤t_cpu_data)]; + atomic_sub(1 << cpu_vpe_id(¤t_cpu_data), &core_cfg->vpe_mask); + smp_mb__after_atomic(); + set_cpu_online(cpu, false); + calculate_cpu_foreign_map(); + irq_migrate_all_off_this_cpu(); + + return 0; +} + +static unsigned cpu_death_sibling; +static enum cpu_death cpu_death; + +void play_dead(void) +{ + unsigned int cpu; + + local_irq_disable(); + idle_task_exit(); + cpu = smp_processor_id(); + cpu_death = CPU_DEATH_POWER; + + pr_debug("CPU%d going offline\n", cpu); + + if (cpu_has_mipsmt || cpu_has_vp) { + /* Look for another online VPE within the core */ + for_each_online_cpu(cpu_death_sibling) { + if (!cpus_are_siblings(cpu, cpu_death_sibling)) + continue; + + /* + * There is an online VPE within the core. Just halt + * this TC and leave the core alone. + */ + cpu_death = CPU_DEATH_HALT; + break; + } + } + + /* This CPU has chosen its way out */ + (void)cpu_report_death(); + + cps_shutdown_this_cpu(cpu_death); + + /* This should never be reached */ + panic("Failed to offline CPU %u", cpu); +} + +static void wait_for_sibling_halt(void *ptr_cpu) +{ + unsigned cpu = (unsigned long)ptr_cpu; + unsigned vpe_id = cpu_vpe_id(&cpu_data[cpu]); + unsigned halted; + unsigned long flags; + + do { + local_irq_save(flags); + settc(vpe_id); + halted = read_tc_c0_tchalt(); + local_irq_restore(flags); + } while (!(halted & TCHALT_H)); +} + +static void cps_cpu_die(unsigned int cpu) +{ + unsigned core = cpu_core(&cpu_data[cpu]); + unsigned int vpe_id = cpu_vpe_id(&cpu_data[cpu]); + ktime_t fail_time; + unsigned stat; + int err; + + /* Wait for the cpu to choose its way out */ + if (!cpu_wait_death(cpu, 5)) { + pr_err("CPU%u: didn't offline\n", cpu); + return; + } + + /* + * Now wait for the CPU to actually offline. Without doing this that + * offlining may race with one or more of: + * + * - Onlining the CPU again. + * - Powering down the core if another VPE within it is offlined. + * - A sibling VPE entering a non-coherent state. + * + * In the non-MT halt case (ie. infinite loop) the CPU is doing nothing + * with which we could race, so do nothing. + */ + if (cpu_death == CPU_DEATH_POWER) { + /* + * Wait for the core to enter a powered down or clock gated + * state, the latter happening when a JTAG probe is connected + * in which case the CPC will refuse to power down the core. + */ + fail_time = ktime_add_ms(ktime_get(), 2000); + do { + mips_cm_lock_other(0, core, 0, CM_GCR_Cx_OTHER_BLOCK_LOCAL); + mips_cpc_lock_other(core); + stat = read_cpc_co_stat_conf(); + stat &= CPC_Cx_STAT_CONF_SEQSTATE; + stat >>= __ffs(CPC_Cx_STAT_CONF_SEQSTATE); + mips_cpc_unlock_other(); + mips_cm_unlock_other(); + + if (stat == CPC_Cx_STAT_CONF_SEQSTATE_D0 || + stat == CPC_Cx_STAT_CONF_SEQSTATE_D2 || + stat == CPC_Cx_STAT_CONF_SEQSTATE_U2) + break; + + /* + * The core ought to have powered down, but didn't & + * now we don't really know what state it's in. It's + * likely that its _pwr_up pin has been wired to logic + * 1 & it powered back up as soon as we powered it + * down... + * + * The best we can do is warn the user & continue in + * the hope that the core is doing nothing harmful & + * might behave properly if we online it later. + */ + if (WARN(ktime_after(ktime_get(), fail_time), + "CPU%u hasn't powered down, seq. state %u\n", + cpu, stat)) + break; + } while (1); + + /* Indicate the core is powered off */ + bitmap_clear(core_power, core, 1); + } else if (cpu_has_mipsmt) { + /* + * Have a CPU with access to the offlined CPUs registers wait + * for its TC to halt. + */ + err = smp_call_function_single(cpu_death_sibling, + wait_for_sibling_halt, + (void *)(unsigned long)cpu, 1); + if (err) + panic("Failed to call remote sibling CPU\n"); + } else if (cpu_has_vp) { + do { + mips_cm_lock_other(0, core, vpe_id, CM_GCR_Cx_OTHER_BLOCK_LOCAL); + stat = read_cpc_co_vp_running(); + mips_cm_unlock_other(); + } while (stat & (1 << vpe_id)); + } +} + +#endif /* CONFIG_HOTPLUG_CPU */ + +static const struct plat_smp_ops cps_smp_ops = { + .smp_setup = cps_smp_setup, + .prepare_cpus = cps_prepare_cpus, + .boot_secondary = cps_boot_secondary, + .init_secondary = cps_init_secondary, + .smp_finish = cps_smp_finish, + .send_ipi_single = mips_smp_send_ipi_single, + .send_ipi_mask = mips_smp_send_ipi_mask, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_disable = cps_cpu_disable, + .cpu_die = cps_cpu_die, +#endif +#ifdef CONFIG_KEXEC + .kexec_nonboot_cpu = cps_kexec_nonboot_cpu, +#endif +}; + +bool mips_cps_smp_in_use(void) +{ + extern const struct plat_smp_ops *mp_ops; + return mp_ops == &cps_smp_ops; +} + +int register_cps_smp_ops(void) +{ + if (!mips_cm_present()) { + pr_warn("MIPS CPS SMP unable to proceed without a CM\n"); + return -ENODEV; + } + + /* check we have a GIC - we need one for IPIs */ + if (!(read_gcr_gic_status() & CM_GCR_GIC_STATUS_EX)) { + pr_warn("MIPS CPS SMP unable to proceed without a GIC\n"); + return -ENODEV; + } + + register_smp_ops(&cps_smp_ops); + return 0; +} |