irqchip: mips-gic: Stop using per-platform mapping tables

Now that the GIC properly uses IRQ domains, kill off the per-platform
routing tables that were used to make the GIC appear transparent.

This includes:
 - removing the mapping tables and the support for applying them,
 - moving GIC IPI support to the GIC driver,
 - properly routing the i8259 through the GIC on Malta, and
 - updating IRQ assignments on SEAD-3 when the GIC is present.

Platforms no longer will pass an interrupt mapping table to gic_init.
Instead, they will pass the CPU interrupt vector (2 - 7) that they
expect the GIC to route interrupts to.  Note that in EIC mode this
value is ignored and all GIC interrupts are routed to EIC vector 1.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7816/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 105 insertions, 96 deletions

diff --git a/drivers/irqchip/irq-mips-gic.c b/drivers/irqchip/irq-mips-gic.c
index 79ab99781534..633a34639388 100644
--- a/drivers/irqchip/irq-mips-gic.c
+++ b/drivers/irqchip/irq-mips-gic.c
@@ -8,6 +8,8 @@
  */
 #include <linux/bitmap.h>
 #include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
 #include <linux/smp.h>
 #include <linux/irq.h>
 #include <linux/clocksource.h>
@@ -22,11 +24,8 @@
 unsigned int gic_frequency;
 unsigned int gic_present;
 unsigned long _gic_base;
-unsigned int gic_irq_base;
 unsigned int gic_irq_flags[GIC_NUM_INTRS];
-
-/* The index into this array is the vector # of the interrupt. */
-struct gic_shared_intr_map gic_shared_intr_map[GIC_NUM_INTRS];
+unsigned int gic_cpu_pin;
 
 struct gic_pcpu_mask {
         DECLARE_BITMAP(pcpu_mask, GIC_NUM_INTRS);
@@ -46,6 +45,8 @@ static struct gic_intrmask_regs intrmask_regs[NR_CPUS];
 static DEFINE_SPINLOCK(gic_lock);
 static struct irq_domain *gic_irq_domain;
 
+static void __gic_irq_dispatch(void);
+
 #if defined(CONFIG_CSRC_GIC) || defined(CONFIG_CEVT_GIC)
 cycle_t gic_read_count(void)
 {
@@ -117,21 +118,6 @@ void gic_send_ipi(unsigned int intr)
         GICWRITE(GIC_REG(SHARED, GIC_SH_WEDGE), 0x80000000 | intr);
 }
 
-static void gic_eic_irq_dispatch(void)
-{
-        unsigned int cause = read_c0_cause();
-        int irq;
-
-        irq = (cause & ST0_IM) >> STATUSB_IP2;
-        if (irq == 0)
-                irq = -1;
-
-        if (irq >= 0)
-                do_IRQ(gic_irq_base + irq);
-        else
-                spurious_interrupt();
-}
-
 static void __init vpe_local_setup(unsigned int numvpes)
 {
         unsigned long timer_intr = GIC_INT_TMR;
@@ -166,16 +152,15 @@ static void __init vpe_local_setup(unsigned int numvpes)
                                  GIC_MAP_TO_PIN_MSK | timer_intr);
                 if (cpu_has_veic) {
                         set_vi_handler(timer_intr + GIC_PIN_TO_VEC_OFFSET,
-                                gic_eic_irq_dispatch);
-                        gic_shared_intr_map[timer_intr + GIC_PIN_TO_VEC_OFFSET].local_intr_mask |= GIC_VPE_RMASK_TIMER_MSK;
+                                       __gic_irq_dispatch);
                 }
 
                 if (vpe_ctl & GIC_VPE_CTL_PERFCNT_RTBL_MSK)
                         GICWRITE(GIC_REG(VPE_OTHER, GIC_VPE_PERFCTR_MAP),
                                  GIC_MAP_TO_PIN_MSK | perf_intr);
                 if (cpu_has_veic) {
-                        set_vi_handler(perf_intr + GIC_PIN_TO_VEC_OFFSET, gic_eic_irq_dispatch);
-                        gic_shared_intr_map[perf_intr + GIC_PIN_TO_VEC_OFFSET].local_intr_mask |= GIC_VPE_RMASK_PERFCNT_MSK;
+                        set_vi_handler(perf_intr + GIC_PIN_TO_VEC_OFFSET,
+                                       __gic_irq_dispatch);
                 }
         }
 }
@@ -343,64 +328,100 @@ static struct irq_chip gic_irq_controller = {
 #endif
 };
 
-static void __init gic_setup_intr(unsigned int intr, unsigned int cpu,
-        unsigned int pin, unsigned int polarity, unsigned int trigtype,
-        unsigned int flags)
+static void __gic_irq_dispatch(void)
 {
-        struct gic_shared_intr_map *map_ptr;
-        int i;
-
-        /* Setup Intr to Pin mapping */
-        if (pin & GIC_MAP_TO_NMI_MSK) {
-                int i;
+        unsigned int intr, virq;
 
-                GICWRITE(GIC_REG_ADDR(SHARED, GIC_SH_MAP_TO_PIN(intr)), pin);
-                /* FIXME: hack to route NMI to all cpu's */
-                for (i = 0; i < NR_CPUS; i += 32) {
-                        GICWRITE(GIC_REG_ADDR(SHARED,
-                                          GIC_SH_MAP_TO_VPE_REG_OFF(intr, i)),
-                                 0xffffffff);
-                }
-        } else {
-                GICWRITE(GIC_REG_ADDR(SHARED, GIC_SH_MAP_TO_PIN(intr)),
-                         GIC_MAP_TO_PIN_MSK | pin);
-                /* Setup Intr to CPU mapping */
-                GIC_SH_MAP_TO_VPE_SMASK(intr, cpu);
-                if (cpu_has_veic) {
-                        set_vi_handler(pin + GIC_PIN_TO_VEC_OFFSET,
-                                gic_eic_irq_dispatch);
-                        map_ptr = &gic_shared_intr_map[pin + GIC_PIN_TO_VEC_OFFSET];
-                        if (map_ptr->num_shared_intr >= GIC_MAX_SHARED_INTR)
-                                BUG();
-                        map_ptr->intr_list[map_ptr->num_shared_intr++] = intr;
-                }
+        while ((intr = gic_get_int()) != GIC_NUM_INTRS) {
+                virq = irq_linear_revmap(gic_irq_domain, intr);
+                do_IRQ(virq);
         }
+}
 
-        /* Setup Intr Polarity */
-        GIC_SET_POLARITY(intr, polarity);
+static void gic_irq_dispatch(unsigned int irq, struct irq_desc *desc)
+{
+        __gic_irq_dispatch();
+}
+
+#ifdef CONFIG_MIPS_GIC_IPI
+static int gic_resched_int_base;
+static int gic_call_int_base;
+
+unsigned int plat_ipi_resched_int_xlate(unsigned int cpu)
+{
+        return gic_resched_int_base + cpu;
+}
 
-        /* Setup Intr Trigger Type */
-        GIC_SET_TRIGGER(intr, trigtype);
+unsigned int plat_ipi_call_int_xlate(unsigned int cpu)
+{
+        return gic_call_int_base + cpu;
+}
 
-        /* Init Intr Masks */
-        GIC_CLR_INTR_MASK(intr);
+static irqreturn_t ipi_resched_interrupt(int irq, void *dev_id)
+{
+        scheduler_ipi();
+
+        return IRQ_HANDLED;
+}
+
+static irqreturn_t ipi_call_interrupt(int irq, void *dev_id)
+{
+        smp_call_function_interrupt();
+
+        return IRQ_HANDLED;
+}
 
-        /* Initialise per-cpu Interrupt software masks */
+static struct irqaction irq_resched = {
+        .handler        = ipi_resched_interrupt,
+        .flags          = IRQF_PERCPU,
+        .name           = "IPI resched"
+};
+
+static struct irqaction irq_call = {
+        .handler        = ipi_call_interrupt,
+        .flags          = IRQF_PERCPU,
+        .name           = "IPI call"
+};
+
+static __init void gic_ipi_init_one(unsigned int intr, int cpu,
+                                    struct irqaction *action)
+{
+        int virq = irq_create_mapping(gic_irq_domain, intr);
+        int i;
+
+        GIC_SH_MAP_TO_VPE_SMASK(intr, cpu);
         for (i = 0; i < NR_CPUS; i++)
                 clear_bit(intr, pcpu_masks[i].pcpu_mask);
         set_bit(intr, pcpu_masks[cpu].pcpu_mask);
 
-        if ((flags & GIC_FLAG_TRANSPARENT) && (cpu_has_veic == 0))
-                GIC_SET_INTR_MASK(intr);
-        if (trigtype == GIC_TRIG_EDGE)
-                gic_irq_flags[intr] |= GIC_TRIG_EDGE;
+        irq_set_irq_type(virq, IRQ_TYPE_EDGE_RISING);
+
+        irq_set_handler(virq, handle_percpu_irq);
+        setup_irq(virq, action);
 }
 
-static void __init gic_basic_init(int numintrs, int numvpes,
-                        struct gic_intr_map *intrmap, int mapsize)
+static __init void gic_ipi_init(void)
 {
-        unsigned int i, cpu;
-        unsigned int pin_offset = 0;
+        int i;
+
+        /* Use last 2 * NR_CPUS interrupts as IPIs */
+        gic_resched_int_base = GIC_NUM_INTRS - nr_cpu_ids;
+        gic_call_int_base = gic_resched_int_base - nr_cpu_ids;
+
+        for (i = 0; i < nr_cpu_ids; i++) {
+                gic_ipi_init_one(gic_call_int_base + i, i, &irq_call);
+                gic_ipi_init_one(gic_resched_int_base + i, i, &irq_resched);
+        }
+}
+#else
+static inline void gic_ipi_init(void)
+{
+}
+#endif
+
+static void __init gic_basic_init(int numintrs, int numvpes)
+{
+        unsigned int i;
 
         board_bind_eic_interrupt = &gic_bind_eic_interrupt;
 
@@ -409,31 +430,8 @@ static void __init gic_basic_init(int numintrs, int numvpes,
                 GIC_SET_POLARITY(i, GIC_POL_POS);
                 GIC_SET_TRIGGER(i, GIC_TRIG_LEVEL);
                 GIC_CLR_INTR_MASK(i);
-                if (i < GIC_NUM_INTRS) {
+                if (i < GIC_NUM_INTRS)
                         gic_irq_flags[i] = 0;
-                        gic_shared_intr_map[i].num_shared_intr = 0;
-                        gic_shared_intr_map[i].local_intr_mask = 0;
-                }
-        }
-
-        /*
-         * In EIC mode, the HW_INT# is offset by (2-1). Need to subtract
-         * one because the GIC will add one (since 0=no intr).
-         */
-        if (cpu_has_veic)
-                pin_offset = (GIC_CPU_TO_VEC_OFFSET - GIC_PIN_TO_VEC_OFFSET);
-
-        /* Setup specifics */
-        for (i = 0; i < mapsize; i++) {
-                cpu = intrmap[i].cpunum;
-                if (cpu == GIC_UNUSED)
-                        continue;
-                gic_setup_intr(i,
-                        intrmap[i].cpunum,
-                        intrmap[i].pin + pin_offset,
-                        intrmap[i].polarity,
-                        intrmap[i].trigtype,
-                        intrmap[i].flags);
         }
 
         vpe_local_setup(numvpes);
@@ -448,7 +446,7 @@ static int gic_irq_domain_map(struct irq_domain *d, unsigned int virq,
 
         spin_lock_irqsave(&gic_lock, flags);
         GICWRITE(GIC_REG_ADDR(SHARED, GIC_SH_MAP_TO_PIN(hw)),
-                 GIC_MAP_TO_PIN_MSK | 0);
+                 GIC_MAP_TO_PIN_MSK | gic_cpu_pin);
         /* Map to VPE 0 by default */
         GIC_SH_MAP_TO_VPE_SMASK(hw, 0);
         set_bit(hw, pcpu_masks[0].pcpu_mask);
@@ -463,8 +461,7 @@ static struct irq_domain_ops gic_irq_domain_ops = {
 };
 
 void __init gic_init(unsigned long gic_base_addr,
-                     unsigned long gic_addrspace_size,
-                     struct gic_intr_map *intr_map, unsigned int intr_map_size,
+                     unsigned long gic_addrspace_size, unsigned int cpu_vec,
                      unsigned int irqbase)
 {
         unsigned int gicconfig;
@@ -472,7 +469,6 @@ void __init gic_init(unsigned long gic_base_addr,
 
         _gic_base = (unsigned long) ioremap_nocache(gic_base_addr,
                                                     gic_addrspace_size);
-        gic_irq_base = irqbase;
 
         GICREAD(GIC_REG(SHARED, GIC_SH_CONFIG), gicconfig);
         numintrs = (gicconfig & GIC_SH_CONFIG_NUMINTRS_MSK) >>
@@ -483,10 +479,23 @@ void __init gic_init(unsigned long gic_base_addr,
                   GIC_SH_CONFIG_NUMVPES_SHF;
         numvpes = numvpes + 1;
 
+        if (cpu_has_veic) {
+                /* Always use vector 1 in EIC mode */
+                gic_cpu_pin = 0;
+                set_vi_handler(gic_cpu_pin + GIC_PIN_TO_VEC_OFFSET,
+                               __gic_irq_dispatch);
+        } else {
+                gic_cpu_pin = cpu_vec - GIC_CPU_PIN_OFFSET;
+                irq_set_chained_handler(MIPS_CPU_IRQ_BASE + cpu_vec,
+                                        gic_irq_dispatch);
+        }
+
         gic_irq_domain = irq_domain_add_simple(NULL, GIC_NUM_INTRS, irqbase,
                                                &gic_irq_domain_ops, NULL);
         if (!gic_irq_domain)
                 panic("Failed to add GIC IRQ domain");
 
-        gic_basic_init(numintrs, numvpes, intr_map, intr_map_size);
+        gic_basic_init(numintrs, numvpes);
+
+        gic_ipi_init();
 }