[PATCH 2/6] Vectored interrupt support.

From: Anoop P.A
Date: Tue Jan 25 2011 - 03:04:09 EST

From: Anoop P A <anoop.pa@xxxxxxxxx>

This patch will add vectored interrupt setups required for MIPS MT modes.
irq_cic has been restructured and moved per irq handler to different file.
irq_cic has been re wrote to support mips MT modes ( VSMP / SMTC )

Signed-off-by: Anoop P A <anoop.pa@xxxxxxxxx>
---
arch/mips/pmc-sierra/msp71xx/Makefile | 2 +-
arch/mips/pmc-sierra/msp71xx/msp_irq.c | 56 ++++++-
arch/mips/pmc-sierra/msp71xx/msp_irq_cic.c | 248 +++++++++++++++++++---------
arch/mips/pmc-sierra/msp71xx/msp_irq_per.c | 179 ++++++++++++++++++++
4 files changed, 397 insertions(+), 88 deletions(-)
create mode 100644 arch/mips/pmc-sierra/msp71xx/msp_irq_per.c

diff --git a/arch/mips/pmc-sierra/msp71xx/Makefile b/arch/mips/pmc-sierra/msp71xx/Makefile
index e107f79..b25f354 100644
--- a/arch/mips/pmc-sierra/msp71xx/Makefile
+++ b/arch/mips/pmc-sierra/msp71xx/Makefile
@@ -6,7 +6,7 @@ obj-y += msp_prom.o msp_setup.o msp_irq.o \
obj-$(CONFIG_HAVE_GPIO_LIB) += gpio.o gpio_extended.o
obj-$(CONFIG_PMC_MSP7120_GW) += msp_hwbutton.o
obj-$(CONFIG_IRQ_MSP_SLP) += msp_irq_slp.o
-obj-$(CONFIG_IRQ_MSP_CIC) += msp_irq_cic.o
+obj-$(CONFIG_IRQ_MSP_CIC) += msp_irq_cic.o msp_irq_per.o
obj-$(CONFIG_PCI) += msp_pci.o
obj-$(CONFIG_MSPETH) += msp_eth.o
obj-$(CONFIG_USB_MSP71XX) += msp_usb.o
diff --git a/arch/mips/pmc-sierra/msp71xx/msp_irq.c b/arch/mips/pmc-sierra/msp71xx/msp_irq.c
index 734d598..4531c4a 100644
--- a/arch/mips/pmc-sierra/msp71xx/msp_irq.c
+++ b/arch/mips/pmc-sierra/msp71xx/msp_irq.c
@@ -19,8 +19,6 @@

#include <msp_int.h>

-extern void msp_int_handle(void);
-
/* SLP bases systems */
extern void msp_slp_irq_init(void);
extern void msp_slp_irq_dispatch(void);
@@ -29,6 +27,18 @@ extern void msp_slp_irq_dispatch(void);
extern void msp_cic_irq_init(void);
extern void msp_cic_irq_dispatch(void);

+/* VSMP support init */
+extern void msp_vsmp_int_init(void);
+
+/* vectored interrupt implementation */
+
+/* SW0/1 interrupts are used for SMP/SMTC */
+static inline void mac0_int_dispatch(void) { do_IRQ(MSP_INT_MAC0); }
+static inline void mac1_int_dispatch(void) { do_IRQ(MSP_INT_MAC1); }
+static inline void mac2_int_dispatch(void) { do_IRQ(MSP_INT_SAR); }
+static inline void usb_int_dispatch(void) { do_IRQ(MSP_INT_USB); }
+static inline void sec_int_dispatch(void) { do_IRQ(MSP_INT_SEC); }
+
/*
* The PMC-Sierra MSP interrupts are arranged in a 3 level cascaded
* hierarchical system. The first level are the direct MIPS interrupts
@@ -96,29 +106,57 @@ asmlinkage void plat_irq_dispatch(struct pt_regs *regs)
do_IRQ(MSP_INT_SW1);
}

-static struct irqaction cascade_msp = {
+static struct irqaction cic_cascade_msp = {
.handler = no_action,
- .name = "MSP cascade"
+ .name = "MSP CIC cascade"
};

+static struct irqaction per_cascade_msp = {
+ .handler = no_action,
+ .name = "MSP PER cascade"
+};

void __init arch_init_irq(void)
{
+ /* assume we'll be using vectored interrupt mode except in UP mode*/
+#ifdef CONFIG_MIPS_MT
+ BUG_ON(!cpu_has_vint);
+#endif
/* initialize the 1st-level CPU based interrupt controller */
mips_cpu_irq_init();

#ifdef CONFIG_IRQ_MSP_CIC
msp_cic_irq_init();
-
+#ifdef CONFIG_MIPS_MT
+ set_vi_handler(MSP_INT_CIC, msp_cic_irq_dispatch);
+ set_vi_handler(MSP_INT_MAC0, mac0_int_dispatch);
+ set_vi_handler(MSP_INT_MAC1, mac1_int_dispatch);
+ set_vi_handler(MSP_INT_SAR, mac2_int_dispatch);
+ set_vi_handler(MSP_INT_USB, usb_int_dispatch);
+ set_vi_handler(MSP_INT_SEC, sec_int_dispatch);
+#ifdef CONFIG_MIPS_MT_SMP
+ msp_vsmp_int_init();
+#elif defined CONFIG_MIPS_MT_SMTC
+ /*Set hwmask for all platform devices */
+ irq_hwmask[MSP_INT_MAC0] = C_IRQ0;
+ irq_hwmask[MSP_INT_MAC1] = C_IRQ1;
+ irq_hwmask[MSP_INT_USB] = C_IRQ2;
+ irq_hwmask[MSP_INT_SAR] = C_IRQ3;
+ irq_hwmask[MSP_INT_SEC] = C_IRQ5;
+
+#endif /* CONFIG_MIPS_MT_SMP */
+#endif /* CONFIG_MIPS_MT */
/* setup the cascaded interrupts */
- setup_irq(MSP_INT_CIC, &cascade_msp);
- setup_irq(MSP_INT_PER, &cascade_msp);
+ setup_irq(MSP_INT_CIC, &cic_cascade_msp);
+ setup_irq(MSP_INT_PER, &per_cascade_msp);
+
#else
/* setup the 2nd-level SLP register based interrupt controller */
+ /* VSMP /SMTC support support is not enabled for SLP */
msp_slp_irq_init();

/* setup the cascaded SLP/PER interrupts */
- setup_irq(MSP_INT_SLP, &cascade_msp);
- setup_irq(MSP_INT_PER, &cascade_msp);
+ setup_irq(MSP_INT_SLP, &cic_cascade_msp);
+ setup_irq(MSP_INT_PER, &per_cascade_msp);
#endif
}
diff --git a/arch/mips/pmc-sierra/msp71xx/msp_irq_cic.c b/arch/mips/pmc-sierra/msp71xx/msp_irq_cic.c
index 07e71ff..e64458a 100644
--- a/arch/mips/pmc-sierra/msp71xx/msp_irq_cic.c
+++ b/arch/mips/pmc-sierra/msp71xx/msp_irq_cic.c
@@ -1,8 +1,7 @@
/*
- * This file define the irq handler for MSP SLM subsystem interrupts.
+ * Copyright 2010 PMC-Sierra, Inc, derived from irq_cpu.c
*
- * Copyright 2005-2007 PMC-Sierra, Inc, derived from irq_cpu.c
- * Author: Andrew Hughes, Andrew_Hughes@xxxxxxxxxxxxxx
+ * This file define the irq handler for MSP CIC subsystem interrupts.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
@@ -16,119 +15,212 @@
#include <linux/bitops.h>
#include <linux/irq.h>

+#include <asm/mipsregs.h>
#include <asm/system.h>

#include <msp_cic_int.h>
#include <msp_regs.h>

/*
- * NOTE: We are only enabling support for VPE0 right now.
+ * External API
*/
+extern void msp_per_irq_init(void);
+extern void msp_per_irq_dispatch(void);

-static inline void unmask_msp_cic_irq(unsigned int irq)
+
+/*
+ * Convenience Macro. Should be somewhere generic.
+ */
+#define get_current_vpe() \
+ ((read_c0_tcbind() >> TCBIND_CURVPE_SHIFT) & TCBIND_CURVPE)
+
+#ifdef CONFIG_SMP
+
+#define LOCK_VPE(flags, mtflags) \
+do { \
+ local_irq_save(flags); \
+ mtflags = dmt(); \
+} while (0)
+
+#define UNLOCK_VPE(flags, mtflags) \
+do { \
+ emt(mtflags); \
+ local_irq_restore(flags);\
+} while (0)
+
+#define LOCK_CORE(flags, mtflags) \
+do { \
+ local_irq_save(flags); \
+ mtflags = dvpe(); \
+} while (0)
+
+#define UNLOCK_CORE(flags, mtflags) \
+do { \
+ evpe(mtflags); \
+ local_irq_restore(flags);\
+} while (0)
+
+#else
+
+#define LOCK_VPE(flags, mtflags)
+#define UNLOCK_VPE(flags, mtflags)
+#endif
+
+/* ensure writes to cic are completed */
+static inline void cic_wmb(void)
{
+ const volatile void __iomem *cic_mem = CIC_VPE0_MSK_REG;
+ volatile u32 dummy_read;

- /* check for PER interrupt range */
- if (irq < MSP_PER_INTBASE)
- *CIC_VPE0_MSK_REG |= (1 << (irq - MSP_CIC_INTBASE));
- else
- *PER_INT_MSK_REG |= (1 << (irq - MSP_PER_INTBASE));
+ wmb();
+ dummy_read = __raw_readl(cic_mem);
+ dummy_read++;
}

-static inline void mask_msp_cic_irq(unsigned int irq)
+static inline void unmask_cic_irq(unsigned int irq)
{
- /* check for PER interrupt range */
- if (irq < MSP_PER_INTBASE)
- *CIC_VPE0_MSK_REG &= ~(1 << (irq - MSP_CIC_INTBASE));
- else
- *PER_INT_MSK_REG &= ~(1 << (irq - MSP_PER_INTBASE));
+ volatile u32 *cic_msk_reg = CIC_VPE0_MSK_REG;
+ int vpe;
+#ifdef CONFIG_SMP
+ unsigned int mtflags;
+ unsigned long flags;
+
+ /*
+ * Make sure we have IRQ affinity. It may have changed while
+ * we were processing the IRQ.
+ */
+ if (!cpumask_test_cpu(smp_processor_id(), irq_desc[irq].affinity))
+ return;
+#endif
+
+ vpe = get_current_vpe();
+ LOCK_VPE(flags, mtflags);
+ cic_msk_reg[vpe] |= (1 << (irq - MSP_CIC_INTBASE));
+ UNLOCK_VPE(flags, mtflags);
+ cic_wmb();
}

-/*
- * While we ack the interrupt interrupts are disabled and thus we don't need
- * to deal with concurrency issues. Same for msp_cic_irq_end.
- */
-static inline void ack_msp_cic_irq(unsigned int irq)
+static inline void mask_cic_irq(unsigned int irq)
{
- mask_msp_cic_irq(irq);
-
+ volatile u32 *cic_msk_reg = CIC_VPE0_MSK_REG;
+ int vpe = get_current_vpe();
+#ifdef CONFIG_SMP
+ unsigned long flags, mtflags;
+#endif
+ LOCK_VPE(flags, mtflags);
+ cic_msk_reg[vpe] &= ~(1 << (irq - MSP_CIC_INTBASE));
+ UNLOCK_VPE(flags, mtflags);
+ cic_wmb();
+}
+static inline void msp_cic_irq_ack(unsigned int irq)
+{
+ mask_cic_irq(irq);
/*
- * only really necessary for 18, 16-14 and sometimes 3:0 (since
- * these can be edge sensitive) but it doesn't hurt for the others.
- */
-
- /* check for PER interrupt range */
- if (irq < MSP_PER_INTBASE)
- *CIC_STS_REG = (1 << (irq - MSP_CIC_INTBASE));
- else
- *PER_INT_STS_REG = (1 << (irq - MSP_PER_INTBASE));
+ * Only really necessary for 18, 16-14 and sometimes 3:0
+ * (since these can be edge sensitive) but it doesn't
+ * hurt for the others
+ */
+ *CIC_STS_REG = (1 << (irq - MSP_CIC_INTBASE));
+ smtc_im_ack_irq(irq);
+}
+
+static void msp_cic_irq_end(unsigned int irq)
+{
+ if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
+ unmask_cic_irq(irq);
+}
+
+/*Note: Limiting to VSMP . Not tested in SMTC */
+
+#ifdef CONFIG_MIPS_MT_SMP
+static inline int msp_cic_irq_set_affinity(unsigned int irq,
+ const struct cpumask *cpumask)
+{
+ int cpu;
+ unsigned long flags;
+ unsigned int mtflags;
+ unsigned long imask = (1 << (irq - MSP_CIC_INTBASE));
+ volatile u32 *cic_mask = (volatile u32 *)CIC_VPE0_MSK_REG;
+
+ /* timer balancing should be disabled in kernel code */
+ BUG_ON(irq == MSP_INT_VPE0_TIMER || irq == MSP_INT_VPE1_TIMER);
+
+ LOCK_CORE(flags, mtflags);
+ /* enable if any of each VPE's TCs require this IRQ */
+ for_each_online_cpu(cpu) {
+ if (cpumask_test_cpu(cpu, cpumask))
+ cic_mask[cpu] |= imask;
+ else
+ cic_mask[cpu] &= ~imask;
+
+ }
+
+ UNLOCK_CORE(flags, mtflags);
+ return 0;
+
}
+#endif

static struct irq_chip msp_cic_irq_controller = {
.name = "MSP_CIC",
- .ack = ack_msp_cic_irq,
- .mask = ack_msp_cic_irq,
- .mask_ack = ack_msp_cic_irq,
- .unmask = unmask_msp_cic_irq,
+ .mask = mask_cic_irq,
+ .mask_ack = msp_cic_irq_ack,
+ .unmask = unmask_cic_irq,
+ .ack = msp_cic_irq_ack,
+ .end = msp_cic_irq_end,
+#ifdef CONFIG_MIPS_MT_SMP
+ .set_affinity = msp_cic_irq_set_affinity,
+#endif
};

-
void __init msp_cic_irq_init(void)
{
int i;
-
/* Mask/clear interrupts. */
*CIC_VPE0_MSK_REG = 0x00000000;
- *PER_INT_MSK_REG = 0x00000000;
+ *CIC_VPE1_MSK_REG = 0x00000000;
*CIC_STS_REG = 0xFFFFFFFF;
- *PER_INT_STS_REG = 0xFFFFFFFF;
-
-#if defined(CONFIG_PMC_MSP7120_GW) || \
- defined(CONFIG_PMC_MSP7120_EVAL)
/*
- * The MSP7120 RG and EVBD boards use IRQ[6:4] for PCI.
- * These inputs map to EXT_INT_POL[6:4] inside the CIC.
- * They are to be active low, level sensitive.
- */
+ * The MSP7120 RG and EVBD boards use IRQ[6:4] for PCI.
+ * These inputs map to EXT_INT_POL[6:4] inside the CIC.
+ * They are to be active low, level sensitive.
+ */
*CIC_EXT_CFG_REG &= 0xFFFF8F8F;
-#endif

/* initialize all the IRQ descriptors */
- for (i = MSP_CIC_INTBASE; i < MSP_PER_INTBASE + 32; i++)
+ for (i = MSP_CIC_INTBASE ; i < MSP_CIC_INTBASE + 32 ; i++) {
set_irq_chip_and_handler(i, &msp_cic_irq_controller,
handle_level_irq);
+#ifdef CONFIG_MIPS_MT_SMTC
+ /* Mask of CIC interrupt */
+ irq_hwmask[i] = C_IRQ4;
+#endif
+ }
+
+ /* Initialize the PER interrupt sub-system */
+ msp_per_irq_init();
}

+/* CIC masked by CIC vector processing before dispatch called */
void msp_cic_irq_dispatch(void)
{
- u32 pending;
- int intbase;
-
- intbase = MSP_CIC_INTBASE;
- pending = *CIC_STS_REG & *CIC_VPE0_MSK_REG;
-
- /* check for PER interrupt */
- if (pending == (1 << (MSP_INT_PER - MSP_CIC_INTBASE))) {
- intbase = MSP_PER_INTBASE;
- pending = *PER_INT_STS_REG & *PER_INT_MSK_REG;
- }
-
- /* check for spurious interrupt */
- if (pending == 0x00000000) {
- printk(KERN_ERR
- "Spurious %s interrupt? status %08x, mask %08x\n",
- (intbase == MSP_CIC_INTBASE) ? "CIC" : "PER",
- (intbase == MSP_CIC_INTBASE) ?
- *CIC_STS_REG : *PER_INT_STS_REG,
- (intbase == MSP_CIC_INTBASE) ?
- *CIC_VPE0_MSK_REG : *PER_INT_MSK_REG);
- return;
- }
-
- /* check for the timer and dispatch it first */
- if ((intbase == MSP_CIC_INTBASE) &&
- (pending & (1 << (MSP_INT_VPE0_TIMER - MSP_CIC_INTBASE))))
+ volatile u32 *cic_msk_reg = (volatile u32 *)CIC_VPE0_MSK_REG;
+ u32 cic_mask;
+ u32 pending;
+ int cic_status = *CIC_STS_REG;
+ cic_mask = cic_msk_reg[get_current_vpe()];
+ pending = cic_status & cic_mask;
+ if (pending & (1 << (MSP_INT_VPE0_TIMER - MSP_CIC_INTBASE))) {
do_IRQ(MSP_INT_VPE0_TIMER);
- else
- do_IRQ(ffs(pending) + intbase - 1);
+ } else if (pending & (1 << (MSP_INT_VPE1_TIMER - MSP_CIC_INTBASE))) {
+ do_IRQ(MSP_INT_VPE1_TIMER);
+ } else if (pending & (1 << (MSP_INT_PER - MSP_CIC_INTBASE))) {
+ msp_per_irq_dispatch();
+ } else if (pending) {
+ do_IRQ(ffs(pending) + MSP_CIC_INTBASE - 1);
+ } else{
+ spurious_interrupt();
+ /* Re-enable the CIC cascaded interrupt. */
+ irq_desc[MSP_INT_CIC].chip->end(MSP_INT_CIC);
+ }
}
diff --git a/arch/mips/pmc-sierra/msp71xx/msp_irq_per.c b/arch/mips/pmc-sierra/msp71xx/msp_irq_per.c
new file mode 100644
index 0000000..949fd14
--- /dev/null
+++ b/arch/mips/pmc-sierra/msp71xx/msp_irq_per.c
@@ -0,0 +1,179 @@
+/*
+ * Copyright 2010 PMC-Sierra, Inc, derived from irq_cpu.c
+ *
+ * This file define the irq handler for MSP PER subsystem interrupts.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/bitops.h>
+
+#include <asm/mipsregs.h>
+#include <asm/system.h>
+
+#include <msp_cic_int.h>
+#include <msp_regs.h>
+
+
+/*
+ * Convenience Macro. Should be somewhere generic.
+ */
+#define get_current_vpe() \
+ ((read_c0_tcbind() >> TCBIND_CURVPE_SHIFT) & TCBIND_CURVPE)
+
+#ifdef CONFIG_SMP
+/*
+ * The PER registers must be protected from concurrent access.
+ */
+
+static DEFINE_SPINLOCK(per_lock);
+#endif
+
+/* ensure writes to per are completed */
+
+static inline void per_wmb(void)
+{
+ const volatile void __iomem *per_mem = PER_INT_MSK_REG;
+ volatile u32 dummy_read;
+
+ wmb();
+ dummy_read = __raw_readl(per_mem);
+ dummy_read++;
+}
+
+static inline void unmask_per_irq(unsigned int irq)
+{
+#ifdef CONFIG_SMP
+ unsigned long flags;
+ spin_lock_irqsave(&per_lock, flags);
+ *PER_INT_MSK_REG |= (1 << (irq - MSP_PER_INTBASE));
+ spin_unlock_irqrestore(&per_lock, flags);
+#else
+ *PER_INT_MSK_REG |= (1 << (irq - MSP_PER_INTBASE));
+#endif
+ per_wmb();
+}
+
+static inline void mask_per_irq(unsigned int irq)
+{
+#ifdef CONFIG_SMP
+ unsigned long flags;
+ spin_lock_irqsave(&per_lock, flags);
+ *PER_INT_MSK_REG &= ~(1 << (irq - MSP_PER_INTBASE));
+ spin_unlock_irqrestore(&per_lock, flags);
+#else
+ *PER_INT_MSK_REG &= ~(1 << (irq - MSP_PER_INTBASE));
+#endif
+ per_wmb();
+}
+
+static inline void msp_per_irq_enable(unsigned int irq)
+{
+ unmask_per_irq(irq);
+}
+
+static inline void msp_per_irq_disable(unsigned int irq)
+{
+ mask_per_irq(irq);
+}
+
+static unsigned int msp_per_irq_startup(unsigned int irq)
+{
+ msp_per_irq_enable(irq);
+ return 0;
+}
+
+#define msp_per_irq_shutdown msp_per_irq_disable
+
+static inline void msp_per_irq_ack(unsigned int irq)
+{
+ mask_per_irq(irq);
+ /*
+ * In the PER interrupt controller, only bits 11 and 10
+ * are write-to-clear, (SPI TX complete, SPI RX complete).
+ * It does nothing for any others.
+ */
+
+ *PER_INT_STS_REG = (1 << (irq - MSP_PER_INTBASE));
+
+ /* Re-enable the CIC cascaded interrupt and return */
+ irq_desc[MSP_INT_CIC].chip->end(MSP_INT_CIC);
+}
+
+static void msp_per_irq_end(unsigned int irq)
+{
+ if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
+ unmask_per_irq(irq);
+}
+
+#ifdef CONFIG_SMP
+static inline int msp_per_irq_set_affinity(unsigned int irq,
+ const struct cpumask *affinity)
+{
+ unsigned long flags;
+ /*
+ * Calls to ack, end, startup, enable are spinlocked in setup_irq and
+ * __do_IRQ.Callers of this function do not spinlock,so we need to
+ * do so ourselves.
+ */
+ raw_spin_lock_irqsave(&irq_desc[irq].lock, flags);
+ msp_per_irq_enable(irq);
+ raw_spin_unlock_irqrestore(&irq_desc[irq].lock, flags);
+ return 0;
+
+}
+#endif
+
+static struct irq_chip msp_per_irq_controller = {
+ .name = "MSP_PER",
+ .startup = msp_per_irq_startup,
+ .shutdown = msp_per_irq_shutdown,
+ .enable = msp_per_irq_enable,
+ .disable = msp_per_irq_disable,
+#ifdef CONFIG_SMP
+ .set_affinity = msp_per_irq_set_affinity,
+#endif
+ .ack = msp_per_irq_ack,
+ .end = msp_per_irq_end,
+};
+
+void __init msp_per_irq_init(void)
+{
+ int i;
+ /* Mask/clear interrupts. */
+ *PER_INT_MSK_REG = 0x00000000;
+ *PER_INT_STS_REG = 0xFFFFFFFF;
+ /* initialize all the IRQ descriptors */
+ for (i = MSP_PER_INTBASE; i < MSP_PER_INTBASE + 32; i++) {
+ irq_desc[i].status = IRQ_DISABLED;
+ irq_desc[i].action = NULL;
+ irq_desc[i].depth = 1;
+ irq_desc[i].chip = &msp_per_irq_controller;
+#ifdef CONFIG_MIPS_MT_SMTC
+ irq_hwmask[i] = C_IRQ4;
+#endif
+ }
+}
+
+void msp_per_irq_dispatch(void)
+{
+ u32 per_mask = *PER_INT_MSK_REG;
+ u32 per_status = *PER_INT_STS_REG;
+ u32 pending;
+
+ pending = per_status & per_mask;
+ if (pending) {
+ do_IRQ(ffs(pending) + MSP_PER_INTBASE - 1);
+ } else {
+ spurious_interrupt();
+ /* Re-enable the CIC cascaded interrupt and return */
+ irq_desc[MSP_INT_CIC].chip->end(MSP_INT_CIC);
+ }
+}
--
1.7.0.4

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