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author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-04-26 22:30:36 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-04-26 22:30:36 +0300 |
commit | 0c855563182001c829065faa17f8e29e9ceffe13 (patch) | |
tree | 815628b2d1e9538915407c67e6c66c7f4ef8bed6 /drivers/irqchip | |
parent | 6b0fbc540c2fc34e55828ef9918cc61528071a01 (diff) | |
parent | ea96292838397682530ac77a429974f8ff5f2df3 (diff) | |
download | linux-0c855563182001c829065faa17f8e29e9ceffe13.tar.xz |
Merge tag 'arm-apple-m1-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM Apple M1 platform support from Arnd Bergmann:
"The Apple M1 is the processor used it all current generation Apple
Macintosh computers. Support for this platform so far is rudimentary,
but it boots and can use framebuffer and serial console over a special
USB cable.
Support for several essential on-chip devices (USB, PCIe, IOMMU, NVMe)
is work in progress but was not ready in time.
A very detailed description of what works is in the commit message of
commit 1bb2fd3880d4 ("Merge tag 'm1-soc-bringup-v5' [..]") and on the
AsahiLinux wiki"
Link: https://lore.kernel.org/linux-arm-kernel/bdb18e9f-fcd7-1e31-2224-19c0e5090706@marcan.st/
* tag 'arm-apple-m1-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
asm-generic/io.h: Unbork ioremap_np() declaration
arm64: apple: Add initial Apple Mac mini (M1, 2020) devicetree
dt-bindings: display: Add apple,simple-framebuffer
arm64: Kconfig: Introduce CONFIG_ARCH_APPLE
irqchip/apple-aic: Add support for the Apple Interrupt Controller
dt-bindings: interrupt-controller: Add DT bindings for apple-aic
arm64: Move ICH_ sysreg bits from arm-gic-v3.h to sysreg.h
of/address: Add infrastructure to declare MMIO as non-posted
asm-generic/io.h: implement pci_remap_cfgspace using ioremap_np
arm64: Implement ioremap_np() to map MMIO as nGnRnE
docs: driver-api: device-io: Document ioremap() variants & access funcs
docs: driver-api: device-io: Document I/O access functions
asm-generic/io.h: Add a non-posted variant of ioremap()
arm64: arch_timer: Implement support for interrupt-names
dt-bindings: timer: arm,arch_timer: Add interrupt-names support
arm64: cputype: Add CPU implementor & types for the Apple M1 cores
dt-bindings: arm: cpus: Add apple,firestorm & icestorm compatibles
dt-bindings: arm: apple: Add bindings for Apple ARM platforms
dt-bindings: vendor-prefixes: Add apple prefix
Diffstat (limited to 'drivers/irqchip')
-rw-r--r-- | drivers/irqchip/Kconfig | 8 | ||||
-rw-r--r-- | drivers/irqchip/Makefile | 1 | ||||
-rw-r--r-- | drivers/irqchip/irq-apple-aic.c | 852 |
3 files changed, 861 insertions, 0 deletions
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index c8f57e3e058d..b90e825df7e1 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -593,4 +593,12 @@ config IRQ_IDT3243X select GENERIC_IRQ_CHIP select IRQ_DOMAIN +config APPLE_AIC + bool "Apple Interrupt Controller (AIC)" + depends on ARM64 + default ARCH_APPLE + help + Support for the Apple Interrupt Controller found on Apple Silicon SoCs, + such as the M1. + endmenu diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile index 18573602a939..f88cbf36a9d2 100644 --- a/drivers/irqchip/Makefile +++ b/drivers/irqchip/Makefile @@ -115,3 +115,4 @@ obj-$(CONFIG_SL28CPLD_INTC) += irq-sl28cpld.o obj-$(CONFIG_MACH_REALTEK_RTL) += irq-realtek-rtl.o obj-$(CONFIG_WPCM450_AIC) += irq-wpcm450-aic.o obj-$(CONFIG_IRQ_IDT3243X) += irq-idt3243x.o +obj-$(CONFIG_APPLE_AIC) += irq-apple-aic.o diff --git a/drivers/irqchip/irq-apple-aic.c b/drivers/irqchip/irq-apple-aic.c new file mode 100644 index 000000000000..c179e27062fd --- /dev/null +++ b/drivers/irqchip/irq-apple-aic.c @@ -0,0 +1,852 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright The Asahi Linux Contributors + * + * Based on irq-lpc32xx: + * Copyright 2015-2016 Vladimir Zapolskiy <vz@mleia.com> + * Based on irq-bcm2836: + * Copyright 2015 Broadcom + */ + +/* + * AIC is a fairly simple interrupt controller with the following features: + * + * - 896 level-triggered hardware IRQs + * - Single mask bit per IRQ + * - Per-IRQ affinity setting + * - Automatic masking on event delivery (auto-ack) + * - Software triggering (ORed with hw line) + * - 2 per-CPU IPIs (meant as "self" and "other", but they are + * interchangeable if not symmetric) + * - Automatic prioritization (single event/ack register per CPU, lower IRQs = + * higher priority) + * - Automatic masking on ack + * - Default "this CPU" register view and explicit per-CPU views + * + * In addition, this driver also handles FIQs, as these are routed to the same + * IRQ vector. These are used for Fast IPIs (TODO), the ARMv8 timer IRQs, and + * performance counters (TODO). + * + * Implementation notes: + * + * - This driver creates two IRQ domains, one for HW IRQs and internal FIQs, + * and one for IPIs. + * - Since Linux needs more than 2 IPIs, we implement a software IRQ controller + * and funnel all IPIs into one per-CPU IPI (the second "self" IPI is unused). + * - FIQ hwirq numbers are assigned after true hwirqs, and are per-cpu. + * - DT bindings use 3-cell form (like GIC): + * - <0 nr flags> - hwirq #nr + * - <1 nr flags> - FIQ #nr + * - nr=0 Physical HV timer + * - nr=1 Virtual HV timer + * - nr=2 Physical guest timer + * - nr=3 Virtual guest timer + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/bits.h> +#include <linux/bitfield.h> +#include <linux/cpuhotplug.h> +#include <linux/io.h> +#include <linux/irqchip.h> +#include <linux/irqdomain.h> +#include <linux/limits.h> +#include <linux/of_address.h> +#include <linux/slab.h> +#include <asm/exception.h> +#include <asm/sysreg.h> +#include <asm/virt.h> + +#include <dt-bindings/interrupt-controller/apple-aic.h> + +/* + * AIC registers (MMIO) + */ + +#define AIC_INFO 0x0004 +#define AIC_INFO_NR_HW GENMASK(15, 0) + +#define AIC_CONFIG 0x0010 + +#define AIC_WHOAMI 0x2000 +#define AIC_EVENT 0x2004 +#define AIC_EVENT_TYPE GENMASK(31, 16) +#define AIC_EVENT_NUM GENMASK(15, 0) + +#define AIC_EVENT_TYPE_HW 1 +#define AIC_EVENT_TYPE_IPI 4 +#define AIC_EVENT_IPI_OTHER 1 +#define AIC_EVENT_IPI_SELF 2 + +#define AIC_IPI_SEND 0x2008 +#define AIC_IPI_ACK 0x200c +#define AIC_IPI_MASK_SET 0x2024 +#define AIC_IPI_MASK_CLR 0x2028 + +#define AIC_IPI_SEND_CPU(cpu) BIT(cpu) + +#define AIC_IPI_OTHER BIT(0) +#define AIC_IPI_SELF BIT(31) + +#define AIC_TARGET_CPU 0x3000 +#define AIC_SW_SET 0x4000 +#define AIC_SW_CLR 0x4080 +#define AIC_MASK_SET 0x4100 +#define AIC_MASK_CLR 0x4180 + +#define AIC_CPU_IPI_SET(cpu) (0x5008 + ((cpu) << 7)) +#define AIC_CPU_IPI_CLR(cpu) (0x500c + ((cpu) << 7)) +#define AIC_CPU_IPI_MASK_SET(cpu) (0x5024 + ((cpu) << 7)) +#define AIC_CPU_IPI_MASK_CLR(cpu) (0x5028 + ((cpu) << 7)) + +#define MASK_REG(x) (4 * ((x) >> 5)) +#define MASK_BIT(x) BIT((x) & GENMASK(4, 0)) + +/* + * IMP-DEF sysregs that control FIQ sources + * Note: sysreg-based IPIs are not supported yet. + */ + +/* Core PMC control register */ +#define SYS_IMP_APL_PMCR0_EL1 sys_reg(3, 1, 15, 0, 0) +#define PMCR0_IMODE GENMASK(10, 8) +#define PMCR0_IMODE_OFF 0 +#define PMCR0_IMODE_PMI 1 +#define PMCR0_IMODE_AIC 2 +#define PMCR0_IMODE_HALT 3 +#define PMCR0_IMODE_FIQ 4 +#define PMCR0_IACT BIT(11) + +/* IPI request registers */ +#define SYS_IMP_APL_IPI_RR_LOCAL_EL1 sys_reg(3, 5, 15, 0, 0) +#define SYS_IMP_APL_IPI_RR_GLOBAL_EL1 sys_reg(3, 5, 15, 0, 1) +#define IPI_RR_CPU GENMASK(7, 0) +/* Cluster only used for the GLOBAL register */ +#define IPI_RR_CLUSTER GENMASK(23, 16) +#define IPI_RR_TYPE GENMASK(29, 28) +#define IPI_RR_IMMEDIATE 0 +#define IPI_RR_RETRACT 1 +#define IPI_RR_DEFERRED 2 +#define IPI_RR_NOWAKE 3 + +/* IPI status register */ +#define SYS_IMP_APL_IPI_SR_EL1 sys_reg(3, 5, 15, 1, 1) +#define IPI_SR_PENDING BIT(0) + +/* Guest timer FIQ enable register */ +#define SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2 sys_reg(3, 5, 15, 1, 3) +#define VM_TMR_FIQ_ENABLE_V BIT(0) +#define VM_TMR_FIQ_ENABLE_P BIT(1) + +/* Deferred IPI countdown register */ +#define SYS_IMP_APL_IPI_CR_EL1 sys_reg(3, 5, 15, 3, 1) + +/* Uncore PMC control register */ +#define SYS_IMP_APL_UPMCR0_EL1 sys_reg(3, 7, 15, 0, 4) +#define UPMCR0_IMODE GENMASK(18, 16) +#define UPMCR0_IMODE_OFF 0 +#define UPMCR0_IMODE_AIC 2 +#define UPMCR0_IMODE_HALT 3 +#define UPMCR0_IMODE_FIQ 4 + +/* Uncore PMC status register */ +#define SYS_IMP_APL_UPMSR_EL1 sys_reg(3, 7, 15, 6, 4) +#define UPMSR_IACT BIT(0) + +#define AIC_NR_FIQ 4 +#define AIC_NR_SWIPI 32 + +/* + * FIQ hwirq index definitions: FIQ sources use the DT binding defines + * directly, except that timers are special. At the irqchip level, the + * two timer types are represented by their access method: _EL0 registers + * or _EL02 registers. In the DT binding, the timers are represented + * by their purpose (HV or guest). This mapping is for when the kernel is + * running at EL2 (with VHE). When the kernel is running at EL1, the + * mapping differs and aic_irq_domain_translate() performs the remapping. + */ + +#define AIC_TMR_EL0_PHYS AIC_TMR_HV_PHYS +#define AIC_TMR_EL0_VIRT AIC_TMR_HV_VIRT +#define AIC_TMR_EL02_PHYS AIC_TMR_GUEST_PHYS +#define AIC_TMR_EL02_VIRT AIC_TMR_GUEST_VIRT + +struct aic_irq_chip { + void __iomem *base; + struct irq_domain *hw_domain; + struct irq_domain *ipi_domain; + int nr_hw; + int ipi_hwirq; +}; + +static DEFINE_PER_CPU(uint32_t, aic_fiq_unmasked); + +static DEFINE_PER_CPU(atomic_t, aic_vipi_flag); +static DEFINE_PER_CPU(atomic_t, aic_vipi_enable); + +static struct aic_irq_chip *aic_irqc; + +static void aic_handle_ipi(struct pt_regs *regs); + +static u32 aic_ic_read(struct aic_irq_chip *ic, u32 reg) +{ + return readl_relaxed(ic->base + reg); +} + +static void aic_ic_write(struct aic_irq_chip *ic, u32 reg, u32 val) +{ + writel_relaxed(val, ic->base + reg); +} + +/* + * IRQ irqchip + */ + +static void aic_irq_mask(struct irq_data *d) +{ + struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d); + + aic_ic_write(ic, AIC_MASK_SET + MASK_REG(irqd_to_hwirq(d)), + MASK_BIT(irqd_to_hwirq(d))); +} + +static void aic_irq_unmask(struct irq_data *d) +{ + struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d); + + aic_ic_write(ic, AIC_MASK_CLR + MASK_REG(d->hwirq), + MASK_BIT(irqd_to_hwirq(d))); +} + +static void aic_irq_eoi(struct irq_data *d) +{ + /* + * Reading the interrupt reason automatically acknowledges and masks + * the IRQ, so we just unmask it here if needed. + */ + if (!irqd_irq_disabled(d) && !irqd_irq_masked(d)) + aic_irq_unmask(d); +} + +static void __exception_irq_entry aic_handle_irq(struct pt_regs *regs) +{ + struct aic_irq_chip *ic = aic_irqc; + u32 event, type, irq; + + do { + /* + * We cannot use a relaxed read here, as reads from DMA buffers + * need to be ordered after the IRQ fires. + */ + event = readl(ic->base + AIC_EVENT); + type = FIELD_GET(AIC_EVENT_TYPE, event); + irq = FIELD_GET(AIC_EVENT_NUM, event); + + if (type == AIC_EVENT_TYPE_HW) + handle_domain_irq(aic_irqc->hw_domain, irq, regs); + else if (type == AIC_EVENT_TYPE_IPI && irq == 1) + aic_handle_ipi(regs); + else if (event != 0) + pr_err_ratelimited("Unknown IRQ event %d, %d\n", type, irq); + } while (event); + + /* + * vGIC maintenance interrupts end up here too, so we need to check + * for them separately. This should never trigger if KVM is working + * properly, because it will have already taken care of clearing it + * on guest exit before this handler runs. + */ + if (is_kernel_in_hyp_mode() && (read_sysreg_s(SYS_ICH_HCR_EL2) & ICH_HCR_EN) && + read_sysreg_s(SYS_ICH_MISR_EL2) != 0) { + pr_err_ratelimited("vGIC IRQ fired and not handled by KVM, disabling.\n"); + sysreg_clear_set_s(SYS_ICH_HCR_EL2, ICH_HCR_EN, 0); + } +} + +static int aic_irq_set_affinity(struct irq_data *d, + const struct cpumask *mask_val, bool force) +{ + irq_hw_number_t hwirq = irqd_to_hwirq(d); + struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d); + int cpu; + + if (force) + cpu = cpumask_first(mask_val); + else + cpu = cpumask_any_and(mask_val, cpu_online_mask); + + aic_ic_write(ic, AIC_TARGET_CPU + hwirq * 4, BIT(cpu)); + irq_data_update_effective_affinity(d, cpumask_of(cpu)); + + return IRQ_SET_MASK_OK; +} + +static int aic_irq_set_type(struct irq_data *d, unsigned int type) +{ + /* + * Some IRQs (e.g. MSIs) implicitly have edge semantics, and we don't + * have a way to find out the type of any given IRQ, so just allow both. + */ + return (type == IRQ_TYPE_LEVEL_HIGH || type == IRQ_TYPE_EDGE_RISING) ? 0 : -EINVAL; +} + +static struct irq_chip aic_chip = { + .name = "AIC", + .irq_mask = aic_irq_mask, + .irq_unmask = aic_irq_unmask, + .irq_eoi = aic_irq_eoi, + .irq_set_affinity = aic_irq_set_affinity, + .irq_set_type = aic_irq_set_type, +}; + +/* + * FIQ irqchip + */ + +static unsigned long aic_fiq_get_idx(struct irq_data *d) +{ + struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d); + + return irqd_to_hwirq(d) - ic->nr_hw; +} + +static void aic_fiq_set_mask(struct irq_data *d) +{ + /* Only the guest timers have real mask bits, unfortunately. */ + switch (aic_fiq_get_idx(d)) { + case AIC_TMR_EL02_PHYS: + sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, VM_TMR_FIQ_ENABLE_P, 0); + isb(); + break; + case AIC_TMR_EL02_VIRT: + sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, VM_TMR_FIQ_ENABLE_V, 0); + isb(); + break; + default: + break; + } +} + +static void aic_fiq_clear_mask(struct irq_data *d) +{ + switch (aic_fiq_get_idx(d)) { + case AIC_TMR_EL02_PHYS: + sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, 0, VM_TMR_FIQ_ENABLE_P); + isb(); + break; + case AIC_TMR_EL02_VIRT: + sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, 0, VM_TMR_FIQ_ENABLE_V); + isb(); + break; + default: + break; + } +} + +static void aic_fiq_mask(struct irq_data *d) +{ + aic_fiq_set_mask(d); + __this_cpu_and(aic_fiq_unmasked, ~BIT(aic_fiq_get_idx(d))); +} + +static void aic_fiq_unmask(struct irq_data *d) +{ + aic_fiq_clear_mask(d); + __this_cpu_or(aic_fiq_unmasked, BIT(aic_fiq_get_idx(d))); +} + +static void aic_fiq_eoi(struct irq_data *d) +{ + /* We mask to ack (where we can), so we need to unmask at EOI. */ + if (__this_cpu_read(aic_fiq_unmasked) & BIT(aic_fiq_get_idx(d))) + aic_fiq_clear_mask(d); +} + +#define TIMER_FIRING(x) \ + (((x) & (ARCH_TIMER_CTRL_ENABLE | ARCH_TIMER_CTRL_IT_MASK | \ + ARCH_TIMER_CTRL_IT_STAT)) == \ + (ARCH_TIMER_CTRL_ENABLE | ARCH_TIMER_CTRL_IT_STAT)) + +static void __exception_irq_entry aic_handle_fiq(struct pt_regs *regs) +{ + /* + * It would be really nice if we had a system register that lets us get + * the FIQ source state without having to peek down into sources... + * but such a register does not seem to exist. + * + * So, we have these potential sources to test for: + * - Fast IPIs (not yet used) + * - The 4 timers (CNTP, CNTV for each of HV and guest) + * - Per-core PMCs (not yet supported) + * - Per-cluster uncore PMCs (not yet supported) + * + * Since not dealing with any of these results in a FIQ storm, + * we check for everything here, even things we don't support yet. + */ + + if (read_sysreg_s(SYS_IMP_APL_IPI_SR_EL1) & IPI_SR_PENDING) { + pr_err_ratelimited("Fast IPI fired. Acking.\n"); + write_sysreg_s(IPI_SR_PENDING, SYS_IMP_APL_IPI_SR_EL1); + } + + if (TIMER_FIRING(read_sysreg(cntp_ctl_el0))) + handle_domain_irq(aic_irqc->hw_domain, + aic_irqc->nr_hw + AIC_TMR_EL0_PHYS, regs); + + if (TIMER_FIRING(read_sysreg(cntv_ctl_el0))) + handle_domain_irq(aic_irqc->hw_domain, + aic_irqc->nr_hw + AIC_TMR_EL0_VIRT, regs); + + if (is_kernel_in_hyp_mode()) { + uint64_t enabled = read_sysreg_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2); + + if ((enabled & VM_TMR_FIQ_ENABLE_P) && + TIMER_FIRING(read_sysreg_s(SYS_CNTP_CTL_EL02))) + handle_domain_irq(aic_irqc->hw_domain, + aic_irqc->nr_hw + AIC_TMR_EL02_PHYS, regs); + + if ((enabled & VM_TMR_FIQ_ENABLE_V) && + TIMER_FIRING(read_sysreg_s(SYS_CNTV_CTL_EL02))) + handle_domain_irq(aic_irqc->hw_domain, + aic_irqc->nr_hw + AIC_TMR_EL02_VIRT, regs); + } + + if ((read_sysreg_s(SYS_IMP_APL_PMCR0_EL1) & (PMCR0_IMODE | PMCR0_IACT)) == + (FIELD_PREP(PMCR0_IMODE, PMCR0_IMODE_FIQ) | PMCR0_IACT)) { + /* + * Not supported yet, let's figure out how to handle this when + * we implement these proprietary performance counters. For now, + * just mask it and move on. + */ + pr_err_ratelimited("PMC FIQ fired. Masking.\n"); + sysreg_clear_set_s(SYS_IMP_APL_PMCR0_EL1, PMCR0_IMODE | PMCR0_IACT, + FIELD_PREP(PMCR0_IMODE, PMCR0_IMODE_OFF)); + } + + if (FIELD_GET(UPMCR0_IMODE, read_sysreg_s(SYS_IMP_APL_UPMCR0_EL1)) == UPMCR0_IMODE_FIQ && + (read_sysreg_s(SYS_IMP_APL_UPMSR_EL1) & UPMSR_IACT)) { + /* Same story with uncore PMCs */ + pr_err_ratelimited("Uncore PMC FIQ fired. Masking.\n"); + sysreg_clear_set_s(SYS_IMP_APL_UPMCR0_EL1, UPMCR0_IMODE, + FIELD_PREP(UPMCR0_IMODE, UPMCR0_IMODE_OFF)); + } +} + +static int aic_fiq_set_type(struct irq_data *d, unsigned int type) +{ + return (type == IRQ_TYPE_LEVEL_HIGH) ? 0 : -EINVAL; +} + +static struct irq_chip fiq_chip = { + .name = "AIC-FIQ", + .irq_mask = aic_fiq_mask, + .irq_unmask = aic_fiq_unmask, + .irq_ack = aic_fiq_set_mask, + .irq_eoi = aic_fiq_eoi, + .irq_set_type = aic_fiq_set_type, +}; + +/* + * Main IRQ domain + */ + +static int aic_irq_domain_map(struct irq_domain *id, unsigned int irq, + irq_hw_number_t hw) +{ + struct aic_irq_chip *ic = id->host_data; + + if (hw < ic->nr_hw) { + irq_domain_set_info(id, irq, hw, &aic_chip, id->host_data, + handle_fasteoi_irq, NULL, NULL); + irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(irq))); + } else { + irq_set_percpu_devid(irq); + irq_domain_set_info(id, irq, hw, &fiq_chip, id->host_data, + handle_percpu_devid_irq, NULL, NULL); + } + + return 0; +} + +static int aic_irq_domain_translate(struct irq_domain *id, + struct irq_fwspec *fwspec, + unsigned long *hwirq, + unsigned int *type) +{ + struct aic_irq_chip *ic = id->host_data; + + if (fwspec->param_count != 3 || !is_of_node(fwspec->fwnode)) + return -EINVAL; + + switch (fwspec->param[0]) { + case AIC_IRQ: + if (fwspec->param[1] >= ic->nr_hw) + return -EINVAL; + *hwirq = fwspec->param[1]; + break; + case AIC_FIQ: + if (fwspec->param[1] >= AIC_NR_FIQ) + return -EINVAL; + *hwirq = ic->nr_hw + fwspec->param[1]; + + /* + * In EL1 the non-redirected registers are the guest's, + * not EL2's, so remap the hwirqs to match. + */ + if (!is_kernel_in_hyp_mode()) { + switch (fwspec->param[1]) { + case AIC_TMR_GUEST_PHYS: + *hwirq = ic->nr_hw + AIC_TMR_EL0_PHYS; + break; + case AIC_TMR_GUEST_VIRT: + *hwirq = ic->nr_hw + AIC_TMR_EL0_VIRT; + break; + case AIC_TMR_HV_PHYS: + case AIC_TMR_HV_VIRT: + return -ENOENT; + default: + break; + } + } + break; + default: + return -EINVAL; + } + + *type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK; + + return 0; +} + +static int aic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *arg) +{ + unsigned int type = IRQ_TYPE_NONE; + struct irq_fwspec *fwspec = arg; + irq_hw_number_t hwirq; + int i, ret; + + ret = aic_irq_domain_translate(domain, fwspec, &hwirq, &type); + if (ret) + return ret; + + for (i = 0; i < nr_irqs; i++) { + ret = aic_irq_domain_map(domain, virq + i, hwirq + i); + if (ret) + return ret; + } + + return 0; +} + +static void aic_irq_domain_free(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs) +{ + int i; + + for (i = 0; i < nr_irqs; i++) { + struct irq_data *d = irq_domain_get_irq_data(domain, virq + i); + + irq_set_handler(virq + i, NULL); + irq_domain_reset_irq_data(d); + } +} + +static const struct irq_domain_ops aic_irq_domain_ops = { + .translate = aic_irq_domain_translate, + .alloc = aic_irq_domain_alloc, + .free = aic_irq_domain_free, +}; + +/* + * IPI irqchip + */ + +static void aic_ipi_mask(struct irq_data *d) +{ + u32 irq_bit = BIT(irqd_to_hwirq(d)); + + /* No specific ordering requirements needed here. */ + atomic_andnot(irq_bit, this_cpu_ptr(&aic_vipi_enable)); +} + +static void aic_ipi_unmask(struct irq_data *d) +{ + struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d); + u32 irq_bit = BIT(irqd_to_hwirq(d)); + + atomic_or(irq_bit, this_cpu_ptr(&aic_vipi_enable)); + + /* + * The atomic_or() above must complete before the atomic_read() + * below to avoid racing aic_ipi_send_mask(). + */ + smp_mb__after_atomic(); + + /* + * If a pending vIPI was unmasked, raise a HW IPI to ourselves. + * No barriers needed here since this is a self-IPI. + */ + if (atomic_read(this_cpu_ptr(&aic_vipi_flag)) & irq_bit) + aic_ic_write(ic, AIC_IPI_SEND, AIC_IPI_SEND_CPU(smp_processor_id())); +} + +static void aic_ipi_send_mask(struct irq_data *d, const struct cpumask *mask) +{ + struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d); + u32 irq_bit = BIT(irqd_to_hwirq(d)); + u32 send = 0; + int cpu; + unsigned long pending; + + for_each_cpu(cpu, mask) { + /* + * This sequence is the mirror of the one in aic_ipi_unmask(); + * see the comment there. Additionally, release semantics + * ensure that the vIPI flag set is ordered after any shared + * memory accesses that precede it. This therefore also pairs + * with the atomic_fetch_andnot in aic_handle_ipi(). + */ + pending = atomic_fetch_or_release(irq_bit, per_cpu_ptr(&aic_vipi_flag, cpu)); + + /* + * The atomic_fetch_or_release() above must complete before the + * atomic_read() below to avoid racing aic_ipi_unmask(). + */ + smp_mb__after_atomic(); + + if (!(pending & irq_bit) && + (atomic_read(per_cpu_ptr(&aic_vipi_enable, cpu)) & irq_bit)) + send |= AIC_IPI_SEND_CPU(cpu); + } + + /* + * The flag writes must complete before the physical IPI is issued + * to another CPU. This is implied by the control dependency on + * the result of atomic_read_acquire() above, which is itself + * already ordered after the vIPI flag write. + */ + if (send) + aic_ic_write(ic, AIC_IPI_SEND, send); +} + +static struct irq_chip ipi_chip = { + .name = "AIC-IPI", + .irq_mask = aic_ipi_mask, + .irq_unmask = aic_ipi_unmask, + .ipi_send_mask = aic_ipi_send_mask, +}; + +/* + * IPI IRQ domain + */ + +static void aic_handle_ipi(struct pt_regs *regs) +{ + int i; + unsigned long enabled, firing; + + /* + * Ack the IPI. We need to order this after the AIC event read, but + * that is enforced by normal MMIO ordering guarantees. + */ + aic_ic_write(aic_irqc, AIC_IPI_ACK, AIC_IPI_OTHER); + + /* + * The mask read does not need to be ordered. Only we can change + * our own mask anyway, so no races are possible here, as long as + * we are properly in the interrupt handler (which is covered by + * the barrier that is part of the top-level AIC handler's readl()). + */ + enabled = atomic_read(this_cpu_ptr(&aic_vipi_enable)); + + /* + * Clear the IPIs we are about to handle. This pairs with the + * atomic_fetch_or_release() in aic_ipi_send_mask(), and needs to be + * ordered after the aic_ic_write() above (to avoid dropping vIPIs) and + * before IPI handling code (to avoid races handling vIPIs before they + * are signaled). The former is taken care of by the release semantics + * of the write portion, while the latter is taken care of by the + * acquire semantics of the read portion. + */ + firing = atomic_fetch_andnot(enabled, this_cpu_ptr(&aic_vipi_flag)) & enabled; + + for_each_set_bit(i, &firing, AIC_NR_SWIPI) + handle_domain_irq(aic_irqc->ipi_domain, i, regs); + + /* + * No ordering needed here; at worst this just changes the timing of + * when the next IPI will be delivered. + */ + aic_ic_write(aic_irqc, AIC_IPI_MASK_CLR, AIC_IPI_OTHER); +} + +static int aic_ipi_alloc(struct irq_domain *d, unsigned int virq, + unsigned int nr_irqs, void *args) +{ + int i; + + for (i = 0; i < nr_irqs; i++) { + irq_set_percpu_devid(virq + i); + irq_domain_set_info(d, virq + i, i, &ipi_chip, d->host_data, + handle_percpu_devid_irq, NULL, NULL); + } + + return 0; +} + +static void aic_ipi_free(struct irq_domain *d, unsigned int virq, unsigned int nr_irqs) +{ + /* Not freeing IPIs */ +} + +static const struct irq_domain_ops aic_ipi_domain_ops = { + .alloc = aic_ipi_alloc, + .free = aic_ipi_free, +}; + +static int aic_init_smp(struct aic_irq_chip *irqc, struct device_node *node) +{ + struct irq_domain *ipi_domain; + int base_ipi; + + ipi_domain = irq_domain_create_linear(irqc->hw_domain->fwnode, AIC_NR_SWIPI, + &aic_ipi_domain_ops, irqc); + if (WARN_ON(!ipi_domain)) + return -ENODEV; + + ipi_domain->flags |= IRQ_DOMAIN_FLAG_IPI_SINGLE; + irq_domain_update_bus_token(ipi_domain, DOMAIN_BUS_IPI); + + base_ipi = __irq_domain_alloc_irqs(ipi_domain, -1, AIC_NR_SWIPI, + NUMA_NO_NODE, NULL, false, NULL); + + if (WARN_ON(!base_ipi)) { + irq_domain_remove(ipi_domain); + return -ENODEV; + } + + set_smp_ipi_range(base_ipi, AIC_NR_SWIPI); + + irqc->ipi_domain = ipi_domain; + + return 0; +} + +static int aic_init_cpu(unsigned int cpu) +{ + /* Mask all hard-wired per-CPU IRQ/FIQ sources */ + + /* Pending Fast IPI FIQs */ + write_sysreg_s(IPI_SR_PENDING, SYS_IMP_APL_IPI_SR_EL1); + + /* Timer FIQs */ + sysreg_clear_set(cntp_ctl_el0, 0, ARCH_TIMER_CTRL_IT_MASK); + sysreg_clear_set(cntv_ctl_el0, 0, ARCH_TIMER_CTRL_IT_MASK); + + /* EL2-only (VHE mode) IRQ sources */ + if (is_kernel_in_hyp_mode()) { + /* Guest timers */ + sysreg_clear_set_s(SYS_IMP_APL_VM_TMR_FIQ_ENA_EL2, + VM_TMR_FIQ_ENABLE_V | VM_TMR_FIQ_ENABLE_P, 0); + + /* vGIC maintenance IRQ */ + sysreg_clear_set_s(SYS_ICH_HCR_EL2, ICH_HCR_EN, 0); + } + + /* PMC FIQ */ + sysreg_clear_set_s(SYS_IMP_APL_PMCR0_EL1, PMCR0_IMODE | PMCR0_IACT, + FIELD_PREP(PMCR0_IMODE, PMCR0_IMODE_OFF)); + + /* Uncore PMC FIQ */ + sysreg_clear_set_s(SYS_IMP_APL_UPMCR0_EL1, UPMCR0_IMODE, + FIELD_PREP(UPMCR0_IMODE, UPMCR0_IMODE_OFF)); + + /* Commit all of the above */ + isb(); + + /* + * Make sure the kernel's idea of logical CPU order is the same as AIC's + * If we ever end up with a mismatch here, we will have to introduce + * a mapping table similar to what other irqchip drivers do. + */ + WARN_ON(aic_ic_read(aic_irqc, AIC_WHOAMI) != smp_processor_id()); + + /* + * Always keep IPIs unmasked at the hardware level (except auto-masking + * by AIC during processing). We manage masks at the vIPI level. + */ + aic_ic_write(aic_irqc, AIC_IPI_ACK, AIC_IPI_SELF | AIC_IPI_OTHER); + aic_ic_write(aic_irqc, AIC_IPI_MASK_SET, AIC_IPI_SELF); + aic_ic_write(aic_irqc, AIC_IPI_MASK_CLR, AIC_IPI_OTHER); + + /* Initialize the local mask state */ + __this_cpu_write(aic_fiq_unmasked, 0); + + return 0; +} + +static int __init aic_of_ic_init(struct device_node *node, struct device_node *parent) +{ + int i; + void __iomem *regs; + u32 info; + struct aic_irq_chip *irqc; + + regs = of_iomap(node, 0); + if (WARN_ON(!regs)) + return -EIO; + + irqc = kzalloc(sizeof(*irqc), GFP_KERNEL); + if (!irqc) + return -ENOMEM; + + aic_irqc = irqc; + irqc->base = regs; + + info = aic_ic_read(irqc, AIC_INFO); + irqc->nr_hw = FIELD_GET(AIC_INFO_NR_HW, info); + + irqc->hw_domain = irq_domain_create_linear(of_node_to_fwnode(node), + irqc->nr_hw + AIC_NR_FIQ, + &aic_irq_domain_ops, irqc); + if (WARN_ON(!irqc->hw_domain)) { + iounmap(irqc->base); + kfree(irqc); + return -ENODEV; + } + + irq_domain_update_bus_token(irqc->hw_domain, DOMAIN_BUS_WIRED); + + if (aic_init_smp(irqc, node)) { + irq_domain_remove(irqc->hw_domain); + iounmap(irqc->base); + kfree(irqc); + return -ENODEV; + } + + set_handle_irq(aic_handle_irq); + set_handle_fiq(aic_handle_fiq); + + for (i = 0; i < BITS_TO_U32(irqc->nr_hw); i++) + aic_ic_write(irqc, AIC_MASK_SET + i * 4, U32_MAX); + for (i = 0; i < BITS_TO_U32(irqc->nr_hw); i++) + aic_ic_write(irqc, AIC_SW_CLR + i * 4, U32_MAX); + for (i = 0; i < irqc->nr_hw; i++) + aic_ic_write(irqc, AIC_TARGET_CPU + i * 4, 1); + + if (!is_kernel_in_hyp_mode()) + pr_info("Kernel running in EL1, mapping interrupts"); + + cpuhp_setup_state(CPUHP_AP_IRQ_APPLE_AIC_STARTING, + "irqchip/apple-aic/ipi:starting", + aic_init_cpu, NULL); + + pr_info("Initialized with %d IRQs, %d FIQs, %d vIPIs\n", + irqc->nr_hw, AIC_NR_FIQ, AIC_NR_SWIPI); + + return 0; +} + +IRQCHIP_DECLARE(apple_m1_aic, "apple,aic", aic_of_ic_init); |