MIPS: SGI-IP27: rework HUB interrupts
This commit rearranges the HUB interrupt code by using MIPS_IRQ_CPU
interrupt handling code and modern Linux IRQ framework features to get
rid of global arrays. It also adds support for irq affinity setting.
Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
diff --git a/arch/mips/sgi-ip27/ip27-irq.c b/arch/mips/sgi-ip27/ip27-irq.c
index f37155e..710a597 100644
--- a/arch/mips/sgi-ip27/ip27-irq.c
+++ b/arch/mips/sgi-ip27/ip27-irq.c
@@ -7,67 +7,234 @@
* Copyright (C) 1999 - 2001 Kanoj Sarcar
*/
-#undef DEBUG
-
-#include <linux/init.h>
-#include <linux/irq.h>
-#include <linux/errno.h>
-#include <linux/signal.h>
-#include <linux/sched.h>
-#include <linux/types.h>
#include <linux/interrupt.h>
+#include <linux/irq.h>
#include <linux/ioport.h>
-#include <linux/timex.h>
-#include <linux/smp.h>
-#include <linux/random.h>
#include <linux/kernel.h>
-#include <linux/kernel_stat.h>
-#include <linux/delay.h>
#include <linux/bitops.h>
-#include <asm/bootinfo.h>
#include <asm/io.h>
-#include <asm/mipsregs.h>
-
-#include <asm/processor.h>
+#include <asm/irq_cpu.h>
+#include <asm/pci/bridge.h>
#include <asm/sn/addrs.h>
#include <asm/sn/agent.h>
#include <asm/sn/arch.h>
#include <asm/sn/hub.h>
#include <asm/sn/intr.h>
-/*
- * Linux has a controller-independent x86 interrupt architecture.
- * every controller has a 'controller-template', that is used
- * by the main code to do the right thing. Each driver-visible
- * interrupt source is transparently wired to the appropriate
- * controller. Thus drivers need not be aware of the
- * interrupt-controller.
- *
- * Various interrupt controllers we handle: 8259 PIC, SMP IO-APIC,
- * PIIX4's internal 8259 PIC and SGI's Visual Workstation Cobalt (IO-)APIC.
- * (IO-APICs assumed to be messaging to Pentium local-APICs)
- *
- * the code is designed to be easily extended with new/different
- * interrupt controllers, without having to do assembly magic.
- */
+struct hub_irq_data {
+ struct bridge_controller *bc;
+ u64 *irq_mask[2];
+ cpuid_t cpu;
+ int bit;
+ int pin;
+};
-extern asmlinkage void ip27_irq(void);
+static DECLARE_BITMAP(hub_irq_map, IP27_HUB_IRQ_COUNT);
-/*
- * Find first bit set
- */
-static int ms1bit(unsigned long x)
+static DEFINE_PER_CPU(unsigned long [2], irq_enable_mask);
+
+static inline int alloc_level(void)
{
- int b = 0, s;
+ int level;
- s = 16; if (x >> 16 == 0) s = 0; b += s; x >>= s;
- s = 8; if (x >> 8 == 0) s = 0; b += s; x >>= s;
- s = 4; if (x >> 4 == 0) s = 0; b += s; x >>= s;
- s = 2; if (x >> 2 == 0) s = 0; b += s; x >>= s;
- s = 1; if (x >> 1 == 0) s = 0; b += s;
+again:
+ level = find_first_zero_bit(hub_irq_map, IP27_HUB_IRQ_COUNT);
+ if (level >= IP27_HUB_IRQ_COUNT)
+ return -ENOSPC;
- return b;
+ if (test_and_set_bit(level, hub_irq_map))
+ goto again;
+
+ return level;
+}
+
+static void enable_hub_irq(struct irq_data *d)
+{
+ struct hub_irq_data *hd = irq_data_get_irq_chip_data(d);
+ unsigned long *mask = per_cpu(irq_enable_mask, hd->cpu);
+
+ set_bit(hd->bit, mask);
+ __raw_writeq(mask[0], hd->irq_mask[0]);
+ __raw_writeq(mask[1], hd->irq_mask[1]);
+}
+
+static void disable_hub_irq(struct irq_data *d)
+{
+ struct hub_irq_data *hd = irq_data_get_irq_chip_data(d);
+ unsigned long *mask = per_cpu(irq_enable_mask, hd->cpu);
+
+ clear_bit(hd->bit, mask);
+ __raw_writeq(mask[0], hd->irq_mask[0]);
+ __raw_writeq(mask[1], hd->irq_mask[1]);
+}
+
+static unsigned int startup_bridge_irq(struct irq_data *d)
+{
+ struct hub_irq_data *hd = irq_data_get_irq_chip_data(d);
+ struct bridge_controller *bc;
+ nasid_t nasid;
+ u32 device;
+ int pin;
+
+ if (!hd)
+ return -EINVAL;
+
+ pin = hd->pin;
+ bc = hd->bc;
+
+ nasid = COMPACT_TO_NASID_NODEID(cpu_to_node(hd->cpu));
+ bridge_write(bc, b_int_addr[pin].addr,
+ (0x20000 | hd->bit | (nasid << 8)));
+ bridge_set(bc, b_int_enable, (1 << pin));
+ bridge_set(bc, b_int_enable, 0x7ffffe00); /* more stuff in int_enable */
+
+ /*
+ * Enable sending of an interrupt clear packt to the hub on a high to
+ * low transition of the interrupt pin.
+ *
+ * IRIX sets additional bits in the address which are documented as
+ * reserved in the bridge docs.
+ */
+ bridge_set(bc, b_int_mode, (1UL << pin));
+
+ /*
+ * We assume the bridge to have a 1:1 mapping between devices
+ * (slots) and intr pins.
+ */
+ device = bridge_read(bc, b_int_device);
+ device &= ~(7 << (pin*3));
+ device |= (pin << (pin*3));
+ bridge_write(bc, b_int_device, device);
+
+ bridge_read(bc, b_wid_tflush);
+
+ enable_hub_irq(d);
+
+ return 0; /* Never anything pending. */
+}
+
+static void shutdown_bridge_irq(struct irq_data *d)
+{
+ struct hub_irq_data *hd = irq_data_get_irq_chip_data(d);
+ struct bridge_controller *bc;
+ int pin = hd->pin;
+
+ if (!hd)
+ return;
+
+ disable_hub_irq(d);
+
+ bc = hd->bc;
+ bridge_clr(bc, b_int_enable, (1 << pin));
+ bridge_read(bc, b_wid_tflush);
+}
+
+static void setup_hub_mask(struct hub_irq_data *hd, const struct cpumask *mask)
+{
+ nasid_t nasid;
+ int cpu;
+
+ cpu = cpumask_first_and(mask, cpu_online_mask);
+ nasid = COMPACT_TO_NASID_NODEID(cpu_to_node(cpu));
+ hd->cpu = cpu;
+ if (!cputoslice(cpu)) {
+ hd->irq_mask[0] = REMOTE_HUB_PTR(nasid, PI_INT_MASK0_A);
+ hd->irq_mask[1] = REMOTE_HUB_PTR(nasid, PI_INT_MASK1_A);
+ } else {
+ hd->irq_mask[0] = REMOTE_HUB_PTR(nasid, PI_INT_MASK0_B);
+ hd->irq_mask[1] = REMOTE_HUB_PTR(nasid, PI_INT_MASK1_B);
+ }
+
+ /* Make sure it's not already pending when we connect it. */
+ REMOTE_HUB_CLR_INTR(nasid, hd->bit);
+}
+
+static int set_affinity_hub_irq(struct irq_data *d, const struct cpumask *mask,
+ bool force)
+{
+ struct hub_irq_data *hd = irq_data_get_irq_chip_data(d);
+
+ if (!hd)
+ return -EINVAL;
+
+ if (irqd_is_started(d))
+ disable_hub_irq(d);
+
+ setup_hub_mask(hd, mask);
+
+ if (irqd_is_started(d))
+ startup_bridge_irq(d);
+
+ irq_data_update_effective_affinity(d, cpumask_of(hd->cpu));
+
+ return 0;
+}
+
+static struct irq_chip hub_irq_type = {
+ .name = "HUB",
+ .irq_startup = startup_bridge_irq,
+ .irq_shutdown = shutdown_bridge_irq,
+ .irq_mask = disable_hub_irq,
+ .irq_unmask = enable_hub_irq,
+ .irq_set_affinity = set_affinity_hub_irq,
+};
+
+int request_bridge_irq(struct bridge_controller *bc, int pin)
+{
+ struct hub_irq_data *hd;
+ struct hub_data *hub;
+ struct irq_desc *desc;
+ int swlevel;
+ int irq;
+
+ hd = kzalloc(sizeof(*hd), GFP_KERNEL);
+ if (!hd)
+ return -ENOMEM;
+
+ swlevel = alloc_level();
+ if (unlikely(swlevel < 0)) {
+ kfree(hd);
+ return -EAGAIN;
+ }
+ irq = swlevel + IP27_HUB_IRQ_BASE;
+
+ hd->bc = bc;
+ hd->bit = swlevel;
+ hd->pin = pin;
+ irq_set_chip_data(irq, hd);
+
+ /* use CPU connected to nearest hub */
+ hub = hub_data(NASID_TO_COMPACT_NODEID(bc->nasid));
+ setup_hub_mask(hd, &hub->h_cpus);
+
+ desc = irq_to_desc(irq);
+ desc->irq_common_data.node = bc->nasid;
+ cpumask_copy(desc->irq_common_data.affinity, &hub->h_cpus);
+
+ return irq;
+}
+
+void ip27_hub_irq_init(void)
+{
+ int i;
+
+ for (i = IP27_HUB_IRQ_BASE;
+ i < (IP27_HUB_IRQ_BASE + IP27_HUB_IRQ_COUNT); i++)
+ irq_set_chip_and_handler(i, &hub_irq_type, handle_level_irq);
+
+ /*
+ * Some interrupts are reserved by hardware or by software convention.
+ * Mark these as reserved right away so they won't be used accidentally
+ * later.
+ */
+ for (i = 0; i <= BASE_PCI_IRQ; i++)
+ set_bit(i, hub_irq_map);
+
+ set_bit(IP_PEND0_6_63, hub_irq_map);
+
+ for (i = NI_BRDCAST_ERR_A; i <= MSC_PANIC_INTR; i++)
+ set_bit(i, hub_irq_map);
}
/*
@@ -82,23 +249,19 @@ static int ms1bit(unsigned long x)
* Kanoj 05.13.00
*/
-static void ip27_do_irq_mask0(void)
+static void ip27_do_irq_mask0(struct irq_desc *desc)
{
- int irq, swlevel;
- u64 pend0, mask0;
cpuid_t cpu = smp_processor_id();
- int pi_int_mask0 =
- (cputoslice(cpu) == 0) ? PI_INT_MASK0_A : PI_INT_MASK0_B;
+ unsigned long *mask = per_cpu(irq_enable_mask, cpu);
+ u64 pend0;
/* copied from Irix intpend0() */
pend0 = LOCAL_HUB_L(PI_INT_PEND0);
- mask0 = LOCAL_HUB_L(pi_int_mask0);
- pend0 &= mask0; /* Pick intrs we should look at */
+ pend0 &= mask[0]; /* Pick intrs we should look at */
if (!pend0)
return;
- swlevel = ms1bit(pend0);
#ifdef CONFIG_SMP
if (pend0 & (1UL << CPU_RESCHED_A_IRQ)) {
LOCAL_HUB_CLR_INTR(CPU_RESCHED_A_IRQ);
@@ -108,106 +271,66 @@ static void ip27_do_irq_mask0(void)
scheduler_ipi();
} else if (pend0 & (1UL << CPU_CALL_A_IRQ)) {
LOCAL_HUB_CLR_INTR(CPU_CALL_A_IRQ);
- irq_enter();
generic_smp_call_function_interrupt();
- irq_exit();
} else if (pend0 & (1UL << CPU_CALL_B_IRQ)) {
LOCAL_HUB_CLR_INTR(CPU_CALL_B_IRQ);
- irq_enter();
generic_smp_call_function_interrupt();
- irq_exit();
} else
#endif
- {
- /* "map" swlevel to irq */
- struct slice_data *si = cpu_data[cpu].data;
-
- irq = si->level_to_irq[swlevel];
- do_IRQ(irq);
- }
+ generic_handle_irq(__ffs(pend0) + IP27_HUB_IRQ_BASE);
LOCAL_HUB_L(PI_INT_PEND0);
}
-static void ip27_do_irq_mask1(void)
+static void ip27_do_irq_mask1(struct irq_desc *desc)
{
- int irq, swlevel;
- u64 pend1, mask1;
cpuid_t cpu = smp_processor_id();
- int pi_int_mask1 = (cputoslice(cpu) == 0) ? PI_INT_MASK1_A : PI_INT_MASK1_B;
- struct slice_data *si = cpu_data[cpu].data;
+ unsigned long *mask = per_cpu(irq_enable_mask, cpu);
+ u64 pend1;
/* copied from Irix intpend0() */
pend1 = LOCAL_HUB_L(PI_INT_PEND1);
- mask1 = LOCAL_HUB_L(pi_int_mask1);
- pend1 &= mask1; /* Pick intrs we should look at */
+ pend1 &= mask[1]; /* Pick intrs we should look at */
if (!pend1)
return;
- swlevel = ms1bit(pend1);
- /* "map" swlevel to irq */
- irq = si->level_to_irq[swlevel];
- LOCAL_HUB_CLR_INTR(swlevel);
- do_IRQ(irq);
+ generic_handle_irq(__ffs(pend1) + IP27_HUB_IRQ_BASE + 64);
LOCAL_HUB_L(PI_INT_PEND1);
}
-static void ip27_prof_timer(void)
+void install_ipi(void)
{
- panic("CPU %d got a profiling interrupt", smp_processor_id());
-}
+ int cpu = smp_processor_id();
+ unsigned long *mask = per_cpu(irq_enable_mask, cpu);
+ int slice = LOCAL_HUB_L(PI_CPU_NUM);
+ int resched, call;
-static void ip27_hub_error(void)
-{
- panic("CPU %d got a hub error interrupt", smp_processor_id());
-}
+ resched = CPU_RESCHED_A_IRQ + slice;
+ set_bit(resched, mask);
+ LOCAL_HUB_CLR_INTR(resched);
-asmlinkage void plat_irq_dispatch(void)
-{
- unsigned long pending = read_c0_cause() & read_c0_status();
- extern unsigned int rt_timer_irq;
+ call = CPU_CALL_A_IRQ + slice;
+ set_bit(call, mask);
+ LOCAL_HUB_CLR_INTR(call);
- if (pending & CAUSEF_IP4)
- do_IRQ(rt_timer_irq);
- else if (pending & CAUSEF_IP2) /* PI_INT_PEND_0 or CC_PEND_{A|B} */
- ip27_do_irq_mask0();
- else if (pending & CAUSEF_IP3) /* PI_INT_PEND_1 */
- ip27_do_irq_mask1();
- else if (pending & CAUSEF_IP5)
- ip27_prof_timer();
- else if (pending & CAUSEF_IP6)
- ip27_hub_error();
+ if (slice == 0) {
+ LOCAL_HUB_S(PI_INT_MASK0_A, mask[0]);
+ LOCAL_HUB_S(PI_INT_MASK1_A, mask[1]);
+ } else {
+ LOCAL_HUB_S(PI_INT_MASK0_B, mask[0]);
+ LOCAL_HUB_S(PI_INT_MASK1_B, mask[1]);
+ }
}
void __init arch_init_irq(void)
{
-}
+ mips_cpu_irq_init();
+ ip27_hub_irq_init();
-void install_ipi(void)
-{
- int slice = LOCAL_HUB_L(PI_CPU_NUM);
- int cpu = smp_processor_id();
- struct slice_data *si = cpu_data[cpu].data;
- struct hub_data *hub = hub_data(cpu_to_node(cpu));
- int resched, call;
-
- resched = CPU_RESCHED_A_IRQ + slice;
- __set_bit(resched, hub->irq_alloc_mask);
- __set_bit(resched, si->irq_enable_mask);
- LOCAL_HUB_CLR_INTR(resched);
-
- call = CPU_CALL_A_IRQ + slice;
- __set_bit(call, hub->irq_alloc_mask);
- __set_bit(call, si->irq_enable_mask);
- LOCAL_HUB_CLR_INTR(call);
-
- if (slice == 0) {
- LOCAL_HUB_S(PI_INT_MASK0_A, si->irq_enable_mask[0]);
- LOCAL_HUB_S(PI_INT_MASK1_A, si->irq_enable_mask[1]);
- } else {
- LOCAL_HUB_S(PI_INT_MASK0_B, si->irq_enable_mask[0]);
- LOCAL_HUB_S(PI_INT_MASK1_B, si->irq_enable_mask[1]);
- }
+ irq_set_percpu_devid(IP27_HUB_PEND0_IRQ);
+ irq_set_chained_handler(IP27_HUB_PEND0_IRQ, ip27_do_irq_mask0);
+ irq_set_percpu_devid(IP27_HUB_PEND1_IRQ);
+ irq_set_chained_handler(IP27_HUB_PEND1_IRQ, ip27_do_irq_mask1);
}