*/
#include <linux/interrupt.h>
-#include <linux/module.h>
-#include <linux/of.h>
-#include <linux/irqdomain.h>
#include <linux/irqchip.h>
-#include "../../drivers/irqchip/irqchip.h"
-#include <asm/sections.h>
-#include <asm/irq.h>
#include <asm/mach_desc.h>
-
-/*
- * Early Hardware specific Interrupt setup
- * -Platform independent, needed for each CPU (not foldable into init_IRQ)
- * -Called very early (start_kernel -> setup_arch -> setup_processor)
- *
- * what it does ?
- * -Optionally, setup the High priority Interrupts as Level 2 IRQs
- */
-void arc_init_IRQ(void)
-{
- int level_mask = 0;
-
- /* setup any high priority Interrupts (Level2 in ARCompact jargon) */
- level_mask |= IS_ENABLED(CONFIG_ARC_IRQ3_LV2) << 3;
- level_mask |= IS_ENABLED(CONFIG_ARC_IRQ5_LV2) << 5;
- level_mask |= IS_ENABLED(CONFIG_ARC_IRQ6_LV2) << 6;
-
- /*
- * Write to register, even if no LV2 IRQs configured to reset it
- * in case bootloader had mucked with it
- */
- write_aux_reg(AUX_IRQ_LEV, level_mask);
-
- if (level_mask)
- pr_info("Level-2 interrupts bitset %x\n", level_mask);
-}
-
-/*
- * ARC700 core includes a simple on-chip intc supporting
- * -per IRQ enable/disable
- * -2 levels of interrupts (high/low)
- * -all interrupts being level triggered
- *
- * To reduce platform code, we assume all IRQs directly hooked-up into intc.
- * Platforms with external intc, hence cascaded IRQs, are free to over-ride
- * below, per IRQ.
- */
-
-static void arc_irq_mask(struct irq_data *data)
-{
- unsigned int ienb;
-
- ienb = read_aux_reg(AUX_IENABLE);
- ienb &= ~(1 << data->irq);
- write_aux_reg(AUX_IENABLE, ienb);
-}
-
-static void arc_irq_unmask(struct irq_data *data)
-{
- unsigned int ienb;
-
- ienb = read_aux_reg(AUX_IENABLE);
- ienb |= (1 << data->irq);
- write_aux_reg(AUX_IENABLE, ienb);
-}
-
-static struct irq_chip onchip_intc = {
- .name = "ARC In-core Intc",
- .irq_mask = arc_irq_mask,
- .irq_unmask = arc_irq_unmask,
-};
-
-static int arc_intc_domain_map(struct irq_domain *d, unsigned int irq,
- irq_hw_number_t hw)
-{
- if (irq == TIMER0_IRQ)
- irq_set_chip_and_handler(irq, &onchip_intc, handle_percpu_irq);
- else
- irq_set_chip_and_handler(irq, &onchip_intc, handle_level_irq);
-
- return 0;
-}
-
-static const struct irq_domain_ops arc_intc_domain_ops = {
- .xlate = irq_domain_xlate_onecell,
- .map = arc_intc_domain_map,
-};
-
-static struct irq_domain *root_domain;
-
-static int __init
-init_onchip_IRQ(struct device_node *intc, struct device_node *parent)
-{
- if (parent)
- panic("DeviceTree incore intc not a root irq controller\n");
-
- root_domain = irq_domain_add_legacy(intc, NR_CPU_IRQS, 0, 0,
- &arc_intc_domain_ops, NULL);
-
- if (!root_domain)
- panic("root irq domain not avail\n");
-
- /* with this we don't need to export root_domain */
- irq_set_default_host(root_domain);
-
- return 0;
-}
-
-IRQCHIP_DECLARE(arc_intc, "snps,arc700-intc", init_onchip_IRQ);
+#include <asm/smp.h>
/*
* Late Interrupt system init called from start_kernel for Boot CPU only
*/
void __init init_IRQ(void)
{
- /* Any external intc can be setup here */
- if (machine_desc->init_irq)
- machine_desc->init_irq();
-
- /* process the entire interrupt tree in one go */
+ /*
+ * process the entire interrupt tree in one go
+ * Any external intc will be setup provided DT chains them
+ * properly
+ */
irqchip_init();
#ifdef CONFIG_SMP
- /* Master CPU can initialize it's side of IPI */
- if (machine_desc->init_smp)
- machine_desc->init_smp(smp_processor_id());
+ /* a SMP H/w block could do IPI IRQ request here */
+ if (plat_smp_ops.init_per_cpu)
+ plat_smp_ops.init_per_cpu(smp_processor_id());
+
+ if (machine_desc->init_per_cpu)
+ machine_desc->init_per_cpu(smp_processor_id());
#endif
}
set_irq_regs(old_regs);
}
+/*
+ * API called for requesting percpu interrupts - called by each CPU
+ * - For boot CPU, actually request the IRQ with genirq core + enables
+ * - For subsequent callers only enable called locally
+ *
+ * Relies on being called by boot cpu first (i.e. request called ahead) of
+ * any enable as expected by genirq. Hence Suitable only for TIMER, IPI
+ * which are guaranteed to be setup on boot core first.
+ * Late probed peripherals such as perf can't use this as there no guarantee
+ * of being called on boot CPU first.
+ */
+
void arc_request_percpu_irq(int irq, int cpu,
irqreturn_t (*isr)(int irq, void *dev),
const char *irq_nm,
if (!cpu) {
int rc;
+#ifdef CONFIG_ISA_ARCOMPACT
/*
- * These 2 calls are essential to making percpu IRQ APIs work
- * Ideally these details could be hidden in irq chip map function
- * but the issue is IPIs IRQs being static (non-DT) and platform
- * specific, so we can't identify them there.
+ * A subsequent request_percpu_irq() fails if percpu_devid is
+ * not set. That in turns sets NOAUTOEN, meaning each core needs
+ * to call enable_percpu_irq()
+ *
+ * For ARCv2, this is done in irq map function since we know
+ * which irqs are strictly per cpu
*/
irq_set_percpu_devid(irq);
- irq_modify_status(irq, IRQ_NOAUTOEN, 0); /* @irq, @clr, @set */
+#endif
rc = request_percpu_irq(irq, isr, irq_nm, percpu_dev);
if (rc)
enable_percpu_irq(irq, 0);
}
-
-/*
- * arch_local_irq_enable - Enable interrupts.
- *
- * 1. Explicitly called to re-enable interrupts
- * 2. Implicitly called from spin_unlock_irq, write_unlock_irq etc
- * which maybe in hard ISR itself
- *
- * Semantics of this function change depending on where it is called from:
- *
- * -If called from hard-ISR, it must not invert interrupt priorities
- * e.g. suppose TIMER is high priority (Level 2) IRQ
- * Time hard-ISR, timer_interrupt( ) calls spin_unlock_irq several times.
- * Here local_irq_enable( ) shd not re-enable lower priority interrupts
- * -If called from soft-ISR, it must re-enable all interrupts
- * soft ISR are low prioity jobs which can be very slow, thus all IRQs
- * must be enabled while they run.
- * Now hardware context wise we may still be in L2 ISR (not done rtie)
- * still we must re-enable both L1 and L2 IRQs
- * Another twist is prev scenario with flow being
- * L1 ISR ==> interrupted by L2 ISR ==> L2 soft ISR
- * here we must not re-enable Ll as prev Ll Interrupt's h/w context will get
- * over-written (this is deficiency in ARC700 Interrupt mechanism)
- */
-
-#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS /* Complex version for 2 IRQ levels */
-
-void arch_local_irq_enable(void)
-{
-
- unsigned long flags;
- flags = arch_local_save_flags();
-
- /* Allow both L1 and L2 at the onset */
- flags |= (STATUS_E1_MASK | STATUS_E2_MASK);
-
- /* Called from hard ISR (between irq_enter and irq_exit) */
- if (in_irq()) {
-
- /* If in L2 ISR, don't re-enable any further IRQs as this can
- * cause IRQ priorities to get upside down. e.g. it could allow
- * L1 be taken while in L2 hard ISR which is wrong not only in
- * theory, it can also cause the dreaded L1-L2-L1 scenario
- */
- if (flags & STATUS_A2_MASK)
- flags &= ~(STATUS_E1_MASK | STATUS_E2_MASK);
-
- /* Even if in L1 ISR, allowe Higher prio L2 IRQs */
- else if (flags & STATUS_A1_MASK)
- flags &= ~(STATUS_E1_MASK);
- }
-
- /* called from soft IRQ, ideally we want to re-enable all levels */
-
- else if (in_softirq()) {
-
- /* However if this is case of L1 interrupted by L2,
- * re-enabling both may cause whaco L1-L2-L1 scenario
- * because ARC700 allows level 1 to interrupt an active L2 ISR
- * Thus we disable both
- * However some code, executing in soft ISR wants some IRQs
- * to be enabled so we re-enable L2 only
- *
- * How do we determine L1 intr by L2
- * -A2 is set (means in L2 ISR)
- * -E1 is set in this ISR's pt_regs->status32 which is
- * saved copy of status32_l2 when l2 ISR happened
- */
- struct pt_regs *pt = get_irq_regs();
- if ((flags & STATUS_A2_MASK) && pt &&
- (pt->status32 & STATUS_A1_MASK)) {
- /*flags &= ~(STATUS_E1_MASK | STATUS_E2_MASK); */
- flags &= ~(STATUS_E1_MASK);
- }
- }
-
- arch_local_irq_restore(flags);
-}
-
-#else /* ! CONFIG_ARC_COMPACT_IRQ_LEVELS */
-
-/*
- * Simpler version for only 1 level of interrupt
- * Here we only Worry about Level 1 Bits
- */
-void arch_local_irq_enable(void)
-{
- unsigned long flags;
-
- /*
- * ARC IDE Drivers tries to re-enable interrupts from hard-isr
- * context which is simply wrong
- */
- if (in_irq()) {
- WARN_ONCE(1, "IRQ enabled from hard-isr");
- return;
- }
-
- flags = arch_local_save_flags();
- flags |= (STATUS_E1_MASK | STATUS_E2_MASK);
- arch_local_irq_restore(flags);
-}
-#endif
-EXPORT_SYMBOL(arch_local_irq_enable);
Code Review / kvmfornfv.git / blobdiff