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metag: Internal and external irqchips

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Meta core internal interrupts (from HWSTATMETA and friends) are vectored
onto the TR1 core trigger for the current thread. This is demultiplexed
in irq-metag.c to individual Linux IRQs for each internal interrupt.

External SoC interrupts (from HWSTATEXT and friends) are vectored onto
the TR2 core trigger for the current thread. This is demultiplexed in
irq-metag-ext.c to individual Linux IRQs for each external SoC interrupt.
The external irqchip has devicetree bindings for configuring the number
of irq banks and the type of masking available.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Cc: Dom Cobley <popcornmix@gmail.com>
Cc: Simon Arlott <simon@fire.lp0.eu>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: linux-doc@vger.kernel.org
This commit is contained in:
James Hogan 2012-10-09 10:54:47 +01:00
parent 63047ea360
commit 5698c50d9d
8 changed files with 1359 additions and 0 deletions
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82
Documentation/devicetree/bindings/metag/meta-intc.txt Normal file
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@ -0,0 +1,82 @@
* Meta External Trigger Controller Binding
This binding specifies what properties must be available in the device tree
representation of a Meta external trigger controller.
Required properties:
- compatible: Specifies the compatibility list for the interrupt controller.
The type shall be <string> and the value shall include "img,meta-intc".
- num-banks: Specifies the number of interrupt banks (each of which can
handle 32 interrupt sources).
- interrupt-controller: The presence of this property identifies the node
as an interupt controller. No property value shall be defined.
- #interrupt-cells: Specifies the number of cells needed to encode an
interrupt source. The type shall be a <u32> and the value shall be 2.
- #address-cells: Specifies the number of cells needed to encode an
address. The type shall be <u32> and the value shall be 0. As such,
'interrupt-map' nodes do not have to specify a parent unit address.
Optional properties:
- no-mask: The controller doesn't have any mask registers.
* Interrupt Specifier Definition
Interrupt specifiers consists of 2 cells encoded as follows:
- <1st-cell>: The interrupt-number that identifies the interrupt source.
- <2nd-cell>: The Linux interrupt flags containing level-sense information,
encoded as follows:
1 = edge triggered
4 = level-sensitive
* Examples
Example 1:
/*
* Meta external trigger block
*/
intc: intc {
// This is an interrupt controller node.
interrupt-controller;
// No address cells so that 'interrupt-map' nodes which
// reference this interrupt controller node do not need a parent
// address specifier.
#address-cells = <0>;
// Two cells to encode interrupt sources.
#interrupt-cells = <2>;
// Number of interrupt banks
num-banks = <2>;
// No HWMASKEXT is available (specify on Chorus2 and Comet ES1)
no-mask;
// Compatible with Meta hardware trigger block.
compatible = "img,meta-intc";
};
Example 2:
/*
* An interrupt generating device that is wired to a Meta external
* trigger block.
*/
uart1: uart@0x02004c00 {
// Interrupt source '5' that is level-sensitive.
// Note that there are only two cells as specified in the
// interrupt parent's '#interrupt-cells' property.
interrupts = <5 4 /* level */>;
// The interrupt controller that this device is wired to.
interrupt-parent = <&intc>;
};

2
MAINTAINERS
View File

@ -5040,6 +5040,8 @@ F: arch/metag/
F: Documentation/metag/
F: Documentation/devicetree/bindings/metag/
F: drivers/clocksource/metag_generic.c
F: drivers/irqchip/irq-metag.c
F: drivers/irqchip/irq-metag-ext.c
MICROBLAZE ARCHITECTURE
M: Michal Simek <monstr@monstr.eu>

5
arch/metag/kernel/irq.c
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@ -6,6 +6,8 @@
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/irqchip/metag-ext.h>
#include <linux/irqchip/metag.h>
#include <linux/irqdomain.h>
#include <linux/ratelimit.h>
@ -258,6 +260,9 @@ void __init init_IRQ(void)
irq_ctx_init(smp_processor_id());
init_internal_IRQ();
init_external_IRQ();
if (machine_desc->init_irq)
machine_desc->init_irq();
}

2
drivers/irqchip/Makefile
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@ -1,4 +1,6 @@
obj-$(CONFIG_ARCH_BCM2835) += irq-bcm2835.o
obj-$(CONFIG_METAG) += irq-metag-ext.o
obj-$(CONFIG_METAG_PERFCOUNTER_IRQS) += irq-metag.o
obj-$(CONFIG_ARCH_SUNXI) += irq-sunxi.o
obj-$(CONFIG_VERSATILE_FPGA_IRQ) += irq-versatile-fpga.o
obj-$(CONFIG_ARCH_SPEAR3XX) += spear-shirq.o

868
drivers/irqchip/irq-metag-ext.c Normal file
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@ -0,0 +1,868 @@
/*
* Meta External interrupt code.
*
* Copyright (C) 2005-2012 Imagination Technologies Ltd.
*
* External interrupts on Meta are configured at two-levels, in the CPU core and
* in the external trigger block. Interrupts from SoC peripherals are
* multiplexed onto a single Meta CPU "trigger" - traditionally it has always
* been trigger 2 (TR2). For info on how de-multiplexing happens check out
* meta_intc_irq_demux().
*/
#include <linux/interrupt.h>
#include <linux/irqchip/metag-ext.h>
#include <linux/irqdomain.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/syscore_ops.h>
#include <asm/irq.h>
#include <asm/hwthread.h>
#define HWSTAT_STRIDE 8
#define HWVEC_BLK_STRIDE 0x1000
/**
* struct meta_intc_priv - private meta external interrupt data
* @nr_banks: Number of interrupt banks
* @domain: IRQ domain for all banks of external IRQs
* @unmasked: Record of unmasked IRQs
* @levels_altered: Record of altered level bits
*/
struct meta_intc_priv {
unsigned int nr_banks;
struct irq_domain *domain;
unsigned long unmasked[4];
#ifdef CONFIG_METAG_SUSPEND_MEM
unsigned long levels_altered[4];
#endif
};
/* Private data for the one and only external interrupt controller */
static struct meta_intc_priv meta_intc_priv;
/**
* meta_intc_offset() - Get the offset into the bank of a hardware IRQ number
* @hw: Hardware IRQ number (within external trigger block)
*
* Returns: Bit offset into the IRQ's bank registers
*/
static unsigned int meta_intc_offset(irq_hw_number_t hw)
{
return hw & 0x1f;
}
/**
* meta_intc_bank() - Get the bank number of a hardware IRQ number
* @hw: Hardware IRQ number (within external trigger block)
*
* Returns: Bank number indicating which register the IRQ's bits are
*/
static unsigned int meta_intc_bank(irq_hw_number_t hw)
{
return hw >> 5;
}
/**
* meta_intc_stat_addr() - Get the address of a HWSTATEXT register
* @hw: Hardware IRQ number (within external trigger block)
*
* Returns: Address of a HWSTATEXT register containing the status bit for
* the specified hardware IRQ number
*/
static void __iomem *meta_intc_stat_addr(irq_hw_number_t hw)
{
return (void __iomem *)(HWSTATEXT +
HWSTAT_STRIDE * meta_intc_bank(hw));
}
/**
* meta_intc_level_addr() - Get the address of a HWLEVELEXT register
* @hw: Hardware IRQ number (within external trigger block)
*
* Returns: Address of a HWLEVELEXT register containing the sense bit for
* the specified hardware IRQ number
*/
static void __iomem *meta_intc_level_addr(irq_hw_number_t hw)
{
return (void __iomem *)(HWLEVELEXT +
HWSTAT_STRIDE * meta_intc_bank(hw));
}
/**
* meta_intc_mask_addr() - Get the address of a HWMASKEXT register
* @hw: Hardware IRQ number (within external trigger block)
*
* Returns: Address of a HWMASKEXT register containing the mask bit for the
* specified hardware IRQ number
*/
static void __iomem *meta_intc_mask_addr(irq_hw_number_t hw)
{
return (void __iomem *)(HWMASKEXT +
HWSTAT_STRIDE * meta_intc_bank(hw));
}
/**
* meta_intc_vec_addr() - Get the vector address of a hardware interrupt
* @hw: Hardware IRQ number (within external trigger block)
*
* Returns: Address of a HWVECEXT register controlling the core trigger to
* vector the IRQ onto
*/
static inline void __iomem *meta_intc_vec_addr(irq_hw_number_t hw)
{
return (void __iomem *)(HWVEC0EXT +
HWVEC_BLK_STRIDE * meta_intc_bank(hw) +
HWVECnEXT_STRIDE * meta_intc_offset(hw));
}
/**
* meta_intc_startup_irq() - set up an external irq
* @data: data for the external irq to start up
*
* Multiplex interrupts for irq onto TR2. Clear any pending interrupts and
* unmask irq, both using the appropriate callbacks.
*/
static unsigned int meta_intc_startup_irq(struct irq_data *data)
{
irq_hw_number_t hw = data->hwirq;
void __iomem *vec_addr = meta_intc_vec_addr(hw);
int thread = hard_processor_id();
/* Perform any necessary acking. */
if (data->chip->irq_ack)
data->chip->irq_ack(data);
/* Wire up this interrupt to the core with HWVECxEXT. */
metag_out32(TBI_TRIG_VEC(TBID_SIGNUM_TR2(thread)), vec_addr);
/* Perform any necessary unmasking. */
data->chip->irq_unmask(data);
return 0;
}
/**
* meta_intc_shutdown_irq() - turn off an external irq
* @data: data for the external irq to turn off
*
* Mask irq using the appropriate callback and stop muxing it onto TR2.
*/
static void meta_intc_shutdown_irq(struct irq_data *data)
{
irq_hw_number_t hw = data->hwirq;
void __iomem *vec_addr = meta_intc_vec_addr(hw);
/* Mask the IRQ */
data->chip->irq_mask(data);
/*
* Disable the IRQ at the core by removing the interrupt from
* the HW vector mapping.
*/
metag_out32(0, vec_addr);
}
/**
* meta_intc_ack_irq() - acknowledge an external irq
* @data: data for the external irq to ack
*
* Clear down an edge interrupt in the status register.
*/
static void meta_intc_ack_irq(struct irq_data *data)
{
irq_hw_number_t hw = data->hwirq;
unsigned int bit = 1 << meta_intc_offset(hw);
void __iomem *stat_addr = meta_intc_stat_addr(hw);
/* Ack the int, if it is still 'on'.
* NOTE - this only works for edge triggered interrupts.
*/
if (metag_in32(stat_addr) & bit)
metag_out32(bit, stat_addr);
}
/**
* record_irq_is_masked() - record the IRQ masked so it doesn't get handled
* @data: data for the external irq to record
*
* This should get called whenever an external IRQ is masked (by whichever
* callback is used). It records the IRQ masked so that it doesn't get handled
* if it still shows up in the status register.
*/
static void record_irq_is_masked(struct irq_data *data)
{
struct meta_intc_priv *priv = &meta_intc_priv;
irq_hw_number_t hw = data->hwirq;
clear_bit(meta_intc_offset(hw), &priv->unmasked[meta_intc_bank(hw)]);
}
/**
* record_irq_is_unmasked() - record the IRQ unmasked so it can be handled
* @data: data for the external irq to record
*
* This should get called whenever an external IRQ is unmasked (by whichever
* callback is used). It records the IRQ unmasked so that it gets handled if it
* shows up in the status register.
*/
static void record_irq_is_unmasked(struct irq_data *data)
{
struct meta_intc_priv *priv = &meta_intc_priv;
irq_hw_number_t hw = data->hwirq;
set_bit(meta_intc_offset(hw), &priv->unmasked[meta_intc_bank(hw)]);
}
/*
* For use by wrapper IRQ drivers
*/
/**
* meta_intc_mask_irq_simple() - minimal mask used by wrapper IRQ drivers
* @data: data for the external irq being masked
*
* This should be called by any wrapper IRQ driver mask functions. it doesn't do
* any masking but records the IRQ as masked so that the core code knows the
* mask has taken place. It is the callers responsibility to ensure that the IRQ
* won't trigger an interrupt to the core.
*/
void meta_intc_mask_irq_simple(struct irq_data *data)
{
record_irq_is_masked(data);
}
/**
* meta_intc_unmask_irq_simple() - minimal unmask used by wrapper IRQ drivers
* @data: data for the external irq being unmasked
*
* This should be called by any wrapper IRQ driver unmask functions. it doesn't
* do any unmasking but records the IRQ as unmasked so that the core code knows
* the unmask has taken place. It is the callers responsibility to ensure that
* the IRQ can now trigger an interrupt to the core.
*/
void meta_intc_unmask_irq_simple(struct irq_data *data)
{
record_irq_is_unmasked(data);
}
/**
* meta_intc_mask_irq() - mask an external irq using HWMASKEXT
* @data: data for the external irq to mask
*
* This is a default implementation of a mask function which makes use of the
* HWMASKEXT registers available in newer versions.
*
* Earlier versions without these registers should use SoC level IRQ masking
* which call the meta_intc_*_simple() functions above, or if that isn't
* available should use the fallback meta_intc_*_nomask() functions below.
*/
static void meta_intc_mask_irq(struct irq_data *data)
{
irq_hw_number_t hw = data->hwirq;
unsigned int bit = 1 << meta_intc_offset(hw);
void __iomem *mask_addr = meta_intc_mask_addr(hw);
unsigned long flags;
record_irq_is_masked(data);
/* update the interrupt mask */
__global_lock2(flags);
metag_out32(metag_in32(mask_addr) & ~bit, mask_addr);
__global_unlock2(flags);
}
/**
* meta_intc_unmask_irq() - unmask an external irq using HWMASKEXT
* @data: data for the external irq to unmask
*
* This is a default implementation of an unmask function which makes use of the
* HWMASKEXT registers available on new versions. It should be paired with
* meta_intc_mask_irq() above.
*/
static void meta_intc_unmask_irq(struct irq_data *data)
{
irq_hw_number_t hw = data->hwirq;
unsigned int bit = 1 << meta_intc_offset(hw);
void __iomem *mask_addr = meta_intc_mask_addr(hw);
unsigned long flags;
record_irq_is_unmasked(data);
/* update the interrupt mask */
__global_lock2(flags);
metag_out32(metag_in32(mask_addr) | bit, mask_addr);
__global_unlock2(flags);
}
/**
* meta_intc_mask_irq_nomask() - mask an external irq by unvectoring
* @data: data for the external irq to mask
*
* This is the version of the mask function for older versions which don't have
* HWMASKEXT registers, or a SoC level means of masking IRQs. Instead the IRQ is
* unvectored from the core and retriggered if necessary later.
*/
static void meta_intc_mask_irq_nomask(struct irq_data *data)
{
irq_hw_number_t hw = data->hwirq;
void __iomem *vec_addr = meta_intc_vec_addr(hw);
record_irq_is_masked(data);
/* there is no interrupt mask, so unvector the interrupt */
metag_out32(0, vec_addr);
}
/**
* meta_intc_unmask_edge_irq_nomask() - unmask an edge irq by revectoring
* @data: data for the external irq to unmask
*
* This is the version of the unmask function for older versions which don't
* have HWMASKEXT registers, or a SoC level means of masking IRQs. Instead the
* IRQ is revectored back to the core and retriggered if necessary.
*
* The retriggering done by this function is specific to edge interrupts.
*/
static void meta_intc_unmask_edge_irq_nomask(struct irq_data *data)
{
irq_hw_number_t hw = data->hwirq;
unsigned int bit = 1 << meta_intc_offset(hw);
void __iomem *stat_addr = meta_intc_stat_addr(hw);
void __iomem *vec_addr = meta_intc_vec_addr(hw);
unsigned int thread = hard_processor_id();
record_irq_is_unmasked(data);
/* there is no interrupt mask, so revector the interrupt */
metag_out32(TBI_TRIG_VEC(TBID_SIGNUM_TR2(thread)), vec_addr);
/*
* Re-trigger interrupt
*
* Writing a 1 toggles, and a 0->1 transition triggers. We only
* retrigger if the status bit is already set, which means we
* need to clear it first. Retriggering is fundamentally racy
* because if the interrupt fires again after we clear it we
* could end up clearing it again and the interrupt handler
* thinking it hasn't fired. Therefore we need to keep trying to
* retrigger until the bit is set.
*/
if (metag_in32(stat_addr) & bit) {
metag_out32(bit, stat_addr);
while (!(metag_in32(stat_addr) & bit))
metag_out32(bit, stat_addr);
}
}
/**
* meta_intc_unmask_level_irq_nomask() - unmask a level irq by revectoring
* @data: data for the external irq to unmask
*
* This is the version of the unmask function for older versions which don't
* have HWMASKEXT registers, or a SoC level means of masking IRQs. Instead the
* IRQ is revectored back to the core and retriggered if necessary.
*
* The retriggering done by this function is specific to level interrupts.
*/
static void meta_intc_unmask_level_irq_nomask(struct irq_data *data)
{
irq_hw_number_t hw = data->hwirq;
unsigned int bit = 1 << meta_intc_offset(hw);
void __iomem *stat_addr = meta_intc_stat_addr(hw);
void __iomem *vec_addr = meta_intc_vec_addr(hw);
unsigned int thread = hard_processor_id();
record_irq_is_unmasked(data);
/* there is no interrupt mask, so revector the interrupt */
metag_out32(TBI_TRIG_VEC(TBID_SIGNUM_TR2(thread)), vec_addr);
/* Re-trigger interrupt */
/* Writing a 1 triggers interrupt */
if (metag_in32(stat_addr) & bit)
metag_out32(bit, stat_addr);
}
/**
* meta_intc_irq_set_type() - set the type of an external irq
* @data: data for the external irq to set the type of
* @flow_type: new irq flow type
*
* Set the flow type of an external interrupt. This updates the irq chip and irq
* handler depending on whether the irq is edge or level sensitive (the polarity
* is ignored), and also sets up the bit in HWLEVELEXT so the hardware knows
* when to trigger.
*/
static int meta_intc_irq_set_type(struct irq_data *data, unsigned int flow_type)
{
#ifdef CONFIG_METAG_SUSPEND_MEM
struct meta_intc_priv *priv = &meta_intc_priv;
#endif
unsigned int irq = data->irq;
irq_hw_number_t hw = data->hwirq;
unsigned int bit = 1 << meta_intc_offset(hw);
void __iomem *level_addr = meta_intc_level_addr(hw);
unsigned long flags;
unsigned int level;
/* update the chip/handler */
if (flow_type & IRQ_TYPE_LEVEL_MASK)
__irq_set_chip_handler_name_locked(irq, &meta_intc_level_chip,
handle_level_irq, NULL);
else
__irq_set_chip_handler_name_locked(irq, &meta_intc_edge_chip,
handle_edge_irq, NULL);
/* and clear/set the bit in HWLEVELEXT */
__global_lock2(flags);
level = metag_in32(level_addr);
if (flow_type & IRQ_TYPE_LEVEL_MASK)
level |= bit;
else
level &= ~bit;
metag_out32(level, level_addr);
#ifdef CONFIG_METAG_SUSPEND_MEM
priv->levels_altered[meta_intc_bank(hw)] |= bit;
#endif
__global_unlock2(flags);
return 0;
}
/**
* meta_intc_irq_demux() - external irq de-multiplexer
* @irq: the virtual interrupt number
* @desc: the interrupt description structure for this irq
*
* The cpu receives an interrupt on TR2 when a SoC interrupt has occurred. It is
* this function's job to demux this irq and figure out exactly which external
* irq needs servicing.
*
* Whilst using TR2 to detect external interrupts is a software convention it is
* (hopefully) unlikely to change.
*/
static void meta_intc_irq_demux(unsigned int irq, struct irq_desc *desc)
{
struct meta_intc_priv *priv = &meta_intc_priv;
irq_hw_number_t hw;
unsigned int bank, irq_no, status;
void __iomem *stat_addr = meta_intc_stat_addr(0);
/*
* Locate which interrupt has caused our handler to run.
*/
for (bank = 0; bank < priv->nr_banks; ++bank) {
/* Which interrupts are currently pending in this bank? */
recalculate:
status = metag_in32(stat_addr) & priv->unmasked[bank];
for (hw = bank*32; status; status >>= 1, ++hw) {
if (status & 0x1) {
/*
* Map the hardware IRQ number to a virtual
* Linux IRQ number.
*/
irq_no = irq_linear_revmap(priv->domain, hw);
/*
* Only fire off external interrupts that are
* registered to be handled by the kernel.
* Other external interrupts are probably being
* handled by other Meta hardware threads.
*/
generic_handle_irq(irq_no);
/*
* The handler may have re-enabled interrupts
* which could have caused a nested invocation
* of this code and make the copy of the
* status register we are using invalid.
*/
goto recalculate;
}
}
stat_addr += HWSTAT_STRIDE;
}
}
#ifdef CONFIG_SMP
/**
* meta_intc_set_affinity() - set the affinity for an interrupt
* @data: data for the external irq to set the affinity of
* @cpumask: cpu mask representing cpus which can handle the interrupt
* @force: whether to force (ignored)
*
* Revector the specified external irq onto a specific cpu's TR2 trigger, so
* that that cpu tends to be the one who handles it.
*/
static int meta_intc_set_affinity(struct irq_data *data,
const struct cpumask *cpumask, bool force)
{
irq_hw_number_t hw = data->hwirq;
void __iomem *vec_addr = meta_intc_vec_addr(hw);
unsigned int cpu, thread;
/*
* Wire up this interrupt from HWVECxEXT to the Meta core.
*
* Note that we can't wire up HWVECxEXT to interrupt more than
* one cpu (the interrupt code doesn't support it), so we just
* pick the first cpu we find in 'cpumask'.
*/
cpu = cpumask_any(cpumask);
thread = cpu_2_hwthread_id[cpu];
metag_out32(TBI_TRIG_VEC(TBID_SIGNUM_TR2(thread)), vec_addr);
return 0;
}
#else
#define meta_intc_set_affinity NULL
#endif
#ifdef CONFIG_PM_SLEEP
#define META_INTC_CHIP_FLAGS (IRQCHIP_MASK_ON_SUSPEND \
| IRQCHIP_SKIP_SET_WAKE)
#else
#define META_INTC_CHIP_FLAGS 0
#endif
/* public edge/level irq chips which SoCs can override */
struct irq_chip meta_intc_edge_chip = {
.irq_startup = meta_intc_startup_irq,
.irq_shutdown = meta_intc_shutdown_irq,
.irq_ack = meta_intc_ack_irq,
.irq_mask = meta_intc_mask_irq,
.irq_unmask = meta_intc_unmask_irq,
.irq_set_type = meta_intc_irq_set_type,
.irq_set_affinity = meta_intc_set_affinity,
.flags = META_INTC_CHIP_FLAGS,
};
struct irq_chip meta_intc_level_chip = {
.irq_startup = meta_intc_startup_irq,
.irq_shutdown = meta_intc_shutdown_irq,
.irq_set_type = meta_intc_irq_set_type,
.irq_mask = meta_intc_mask_irq,
.irq_unmask = meta_intc_unmask_irq,
.irq_set_affinity = meta_intc_set_affinity,
.flags = META_INTC_CHIP_FLAGS,
};
/**
* meta_intc_map() - map an external irq
* @d: irq domain of external trigger block
* @irq: virtual irq number
* @hw: hardware irq number within external trigger block
*
* This sets up a virtual irq for a specified hardware interrupt. The irq chip
* and handler is configured, using the HWLEVELEXT registers to determine
* edge/level flow type. These registers will have been set when the irq type is
* set (or set to a default at init time).
*/
static int meta_intc_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
unsigned int bit = 1 << meta_intc_offset(hw);
void __iomem *level_addr = meta_intc_level_addr(hw);
/* Go by the current sense in the HWLEVELEXT register */
if (metag_in32(level_addr) & bit)
irq_set_chip_and_handler(irq, &meta_intc_level_chip,
handle_level_irq);
else
irq_set_chip_and_handler(irq, &meta_intc_edge_chip,
handle_edge_irq);
return 0;
}
static const struct irq_domain_ops meta_intc_domain_ops = {
.map = meta_intc_map,
.xlate = irq_domain_xlate_twocell,
};
#ifdef CONFIG_METAG_SUSPEND_MEM
/**
* struct meta_intc_context - suspend context
* @levels: State of HWLEVELEXT registers
* @masks: State of HWMASKEXT registers
* @vectors: State of HWVECEXT registers
* @txvecint: State of TxVECINT registers
*
* This structure stores the IRQ state across suspend.
*/
struct meta_intc_context {
u32 levels[4];
u32 masks[4];
u8 vectors[4*32];
u8 txvecint[4][4];
};
/* suspend context */
static struct meta_intc_context *meta_intc_context;
/**
* meta_intc_suspend() - store irq state
*
* To avoid interfering with other threads we only save the IRQ state of IRQs in
* use by Linux.
*/
static int meta_intc_suspend(void)
{
struct meta_intc_priv *priv = &meta_intc_priv;
int i, j;
irq_hw_number_t hw;
unsigned int bank;
unsigned long flags;
struct meta_intc_context *context;
void __iomem *level_addr, *mask_addr, *vec_addr;
u32 mask, bit;
context = kzalloc(sizeof(*context), GFP_ATOMIC);
if (!context)
return -ENOMEM;
hw = 0;
level_addr = meta_intc_level_addr(0);
mask_addr = meta_intc_mask_addr(0);
for (bank = 0; bank < priv->nr_banks; ++bank) {
vec_addr = meta_intc_vec_addr(hw);
/* create mask of interrupts in use */
mask = 0;
for (bit = 1; bit; bit <<= 1) {
i = irq_linear_revmap(priv->domain, hw);
/* save mapped irqs which are enabled or have actions */
if (i && (!irqd_irq_disabled(irq_get_irq_data(i)) ||
irq_has_action(i))) {
mask |= bit;
/* save trigger vector */
context->vectors[hw] = metag_in32(vec_addr);
}
++hw;
vec_addr += HWVECnEXT_STRIDE;
}
/* save level state if any IRQ levels altered */
if (priv->levels_altered[bank])
context->levels[bank] = metag_in32(level_addr);
/* save mask state if any IRQs in use */
if (mask)
context->masks[bank] = metag_in32(mask_addr);
level_addr += HWSTAT_STRIDE;
mask_addr += HWSTAT_STRIDE;
}
/* save trigger matrixing */
__global_lock2(flags);
for (i = 0; i < 4; ++i)
for (j = 0; j < 4; ++j)
context->txvecint[i][j] = metag_in32(T0VECINT_BHALT +
TnVECINT_STRIDE*i +
8*j);
__global_unlock2(flags);
meta_intc_context = context;
return 0;
}
/**
* meta_intc_resume() - restore saved irq state
*
* Restore the saved IRQ state and drop it.
*/
static void meta_intc_resume(void)
{
struct meta_intc_priv *priv = &meta_intc_priv;
int i, j;
irq_hw_number_t hw;
unsigned int bank;
unsigned long flags;
struct meta_intc_context *context = meta_intc_context;
void __iomem *level_addr, *mask_addr, *vec_addr;
u32 mask, bit, tmp;
meta_intc_context = NULL;
hw = 0;
level_addr = meta_intc_level_addr(0);
mask_addr = meta_intc_mask_addr(0);
for (bank = 0; bank < priv->nr_banks; ++bank) {
vec_addr = meta_intc_vec_addr(hw);
/* create mask of interrupts in use */
mask = 0;
for (bit = 1; bit; bit <<= 1) {
i = irq_linear_revmap(priv->domain, hw);
/* restore mapped irqs, enabled or with actions */
if (i && (!irqd_irq_disabled(irq_get_irq_data(i)) ||
irq_has_action(i))) {
mask |= bit;
/* restore trigger vector */
metag_out32(context->vectors[hw], vec_addr);
}
++hw;
vec_addr += HWVECnEXT_STRIDE;
}
if (mask) {
/* restore mask state */
__global_lock2(flags);
tmp = metag_in32(mask_addr);
tmp = (tmp & ~mask) | (context->masks[bank] & mask);
metag_out32(tmp, mask_addr);
__global_unlock2(flags);
}
mask = priv->levels_altered[bank];
if (mask) {
/* restore level state */
__global_lock2(flags);
tmp = metag_in32(level_addr);
tmp = (tmp & ~mask) | (context->levels[bank] & mask);
metag_out32(tmp, level_addr);
__global_unlock2(flags);
}
level_addr += HWSTAT_STRIDE;
mask_addr += HWSTAT_STRIDE;
}
/* restore trigger matrixing */
__global_lock2(flags);
for (i = 0; i < 4; ++i) {
for (j = 0; j < 4; ++j) {
metag_out32(context->txvecint[i][j],
T0VECINT_BHALT +
TnVECINT_STRIDE*i +
8*j);
}
}
__global_unlock2(flags);
kfree(context);
}
static struct syscore_ops meta_intc_syscore_ops = {
.suspend = meta_intc_suspend,
.resume = meta_intc_resume,
};
static void __init meta_intc_init_syscore_ops(struct meta_intc_priv *priv)
{
register_syscore_ops(&meta_intc_syscore_ops);
}
#else
#define meta_intc_init_syscore_ops(priv) do {} while (0)
#endif
/**
* meta_intc_init_cpu() - register with a Meta cpu
* @priv: private interrupt controller data
* @cpu: the CPU to register on
*
* Configure @cpu's TR2 irq so that we can demux external irqs.
*/
static void __init meta_intc_init_cpu(struct meta_intc_priv *priv, int cpu)
{
unsigned int thread = cpu_2_hwthread_id[cpu];
unsigned int signum = TBID_SIGNUM_TR2(thread);
int irq = tbisig_map(signum);
/* Register the multiplexed IRQ handler */
irq_set_chained_handler(irq, meta_intc_irq_demux);
irq_set_irq_type(irq, IRQ_TYPE_LEVEL_LOW);
}
/**
* meta_intc_no_mask() - indicate lack of HWMASKEXT registers
*
* Called from SoC code (or init code below) to dynamically indicate the lack of
* HWMASKEXT registers (for example depending on some SoC revision register).
* This alters the irq mask and unmask callbacks to use the fallback
* unvectoring/retriggering technique instead of using HWMASKEXT registers.
*/
void __init meta_intc_no_mask(void)
{
meta_intc_edge_chip.irq_mask = meta_intc_mask_irq_nomask;
meta_intc_edge_chip.irq_unmask = meta_intc_unmask_edge_irq_nomask;
meta_intc_level_chip.irq_mask = meta_intc_mask_irq_nomask;
meta_intc_level_chip.irq_unmask = meta_intc_unmask_level_irq_nomask;
}
/**
* init_external_IRQ() - initialise the external irq controller
*
* Set up the external irq controller using device tree properties. This is
* called from init_IRQ().
*/
int __init init_external_IRQ(void)
{
struct meta_intc_priv *priv = &meta_intc_priv;
struct device_node *node;
int ret, cpu;
u32 val;
bool no_masks = false;
node = of_find_compatible_node(NULL, NULL, "img,meta-intc");
if (!node)
return -ENOENT;
/* Get number of banks */
ret = of_property_read_u32(node, "num-banks", &val);
if (ret) {
pr_err("meta-intc: No num-banks property found\n");
return ret;
}
if (val < 1 || val > 4) {
pr_err("meta-intc: num-banks (%u) out of range\n", val);
return -EINVAL;
}
priv->nr_banks = val;
/* Are any mask registers present? */
if (of_get_property(node, "no-mask", NULL))
no_masks = true;
/* No HWMASKEXT registers present? */
if (no_masks)
meta_intc_no_mask();
/* Set up an IRQ domain */
/*
* This is a legacy IRQ domain for now until all the platform setup code
* has been converted to devicetree.
*/
priv->domain = irq_domain_add_linear(node, priv->nr_banks*32,
&meta_intc_domain_ops, priv);
if (unlikely(!priv->domain)) {
pr_err("meta-intc: cannot add IRQ domain\n");
return -ENOMEM;
}
/* Setup TR2 for all cpus. */
for_each_possible_cpu(cpu)
meta_intc_init_cpu(priv, cpu);
/* Set up system suspend/resume callbacks */
meta_intc_init_syscore_ops(priv);
pr_info("meta-intc: External IRQ controller initialised (%u IRQs)\n",
priv->nr_banks*32);
return 0;
}

343
drivers/irqchip/irq-metag.c Normal file
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/*
* Meta internal (HWSTATMETA) interrupt code.
*
* Copyright (C) 2011-2012 Imagination Technologies Ltd.
*
* This code is based on the code in SoC/common/irq.c and SoC/comet/irq.c
* The code base could be generalised/merged as a lot of the functionality is
* similar. Until this is done, we try to keep the code simple here.
*/
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irqdomain.h>
#include <asm/irq.h>
#include <asm/hwthread.h>
#define PERF0VECINT 0x04820580
#define PERF1VECINT 0x04820588
#define PERF0TRIG_OFFSET 16
#define PERF1TRIG_OFFSET 17
/**
* struct metag_internal_irq_priv - private meta internal interrupt data
* @domain: IRQ domain for all internal Meta IRQs (HWSTATMETA)
* @unmasked: Record of unmasked IRQs
*/
struct metag_internal_irq_priv {
struct irq_domain *domain;
unsigned long unmasked;
};
/* Private data for the one and only internal interrupt controller */
static struct metag_internal_irq_priv metag_internal_irq_priv;
static unsigned int metag_internal_irq_startup(struct irq_data *data);
static void metag_internal_irq_shutdown(struct irq_data *data);
static void metag_internal_irq_ack(struct irq_data *data);
static void metag_internal_irq_mask(struct irq_data *data);
static void metag_internal_irq_unmask(struct irq_data *data);
#ifdef CONFIG_SMP
static int metag_internal_irq_set_affinity(struct irq_data *data,
const struct cpumask *cpumask, bool force);
#endif
static struct irq_chip internal_irq_edge_chip = {
.name = "HWSTATMETA-IRQ",
.irq_startup = metag_internal_irq_startup,
.irq_shutdown = metag_internal_irq_shutdown,
.irq_ack = metag_internal_irq_ack,
.irq_mask = metag_internal_irq_mask,
.irq_unmask = metag_internal_irq_unmask,
#ifdef CONFIG_SMP
.irq_set_affinity = metag_internal_irq_set_affinity,
#endif
};
/*
* metag_hwvec_addr - get the address of *VECINT regs of irq
*
* This function is a table of supported triggers on HWSTATMETA
* Could do with a structure, but better keep it simple. Changes
* in this code should be rare.
*/
static inline void __iomem *metag_hwvec_addr(irq_hw_number_t hw)
{
void __iomem *addr;
switch (hw) {
case PERF0TRIG_OFFSET:
addr = (void __iomem *)PERF0VECINT;
break;
case PERF1TRIG_OFFSET:
addr = (void __iomem *)PERF1VECINT;
break;
default:
addr = NULL;
break;
}
return addr;
}
/*
* metag_internal_startup - setup an internal irq
* @irq: the irq to startup
*
* Multiplex interrupts for @irq onto TR1. Clear any pending
* interrupts.
*/
static unsigned int metag_internal_irq_startup(struct irq_data *data)
{
/* Clear (toggle) the bit in HWSTATMETA for our interrupt. */
metag_internal_irq_ack(data);
/* Enable the interrupt by unmasking it */
metag_internal_irq_unmask(data);
return 0;
}
/*
* metag_internal_irq_shutdown - turn off the irq
* @irq: the irq number to turn off
*
* Mask @irq and clear any pending interrupts.
* Stop muxing @irq onto TR1.
*/
static void metag_internal_irq_shutdown(struct irq_data *data)
{
/* Disable the IRQ at the core by masking it. */
metag_internal_irq_mask(data);
/* Clear (toggle) the bit in HWSTATMETA for our interrupt. */
metag_internal_irq_ack(data);
}
/*
* metag_internal_irq_ack - acknowledge irq
* @irq: the irq to ack
*/
static void metag_internal_irq_ack(struct irq_data *data)
{
irq_hw_number_t hw = data->hwirq;
unsigned int bit = 1 << hw;
if (metag_in32(HWSTATMETA) & bit)
metag_out32(bit, HWSTATMETA);
}
/**
* metag_internal_irq_mask() - mask an internal irq by unvectoring
* @data: data for the internal irq to mask
*
* HWSTATMETA has no mask register. Instead the IRQ is unvectored from the core
* and retriggered if necessary later.
*/
static void metag_internal_irq_mask(struct irq_data *data)
{
struct metag_internal_irq_priv *priv = &metag_internal_irq_priv;
irq_hw_number_t hw = data->hwirq;
void __iomem *vec_addr = metag_hwvec_addr(hw);
clear_bit(hw, &priv->unmasked);
/* there is no interrupt mask, so unvector the interrupt */
metag_out32(0, vec_addr);
}
/**
* meta_intc_unmask_edge_irq_nomask() - unmask an edge irq by revectoring
* @data: data for the internal irq to unmask
*
* HWSTATMETA has no mask register. Instead the IRQ is revectored back to the
* core and retriggered if necessary.
*/
static void metag_internal_irq_unmask(struct irq_data *data)
{
struct metag_internal_irq_priv *priv = &metag_internal_irq_priv;
irq_hw_number_t hw = data->hwirq;
unsigned int bit = 1 << hw;
void __iomem *vec_addr = metag_hwvec_addr(hw);
unsigned int thread = hard_processor_id();
set_bit(hw, &priv->unmasked);
/* there is no interrupt mask, so revector the interrupt */
metag_out32(TBI_TRIG_VEC(TBID_SIGNUM_TR1(thread)), vec_addr);
/*
* Re-trigger interrupt
*
* Writing a 1 toggles, and a 0->1 transition triggers. We only
* retrigger if the status bit is already set, which means we
* need to clear it first. Retriggering is fundamentally racy
* because if the interrupt fires again after we clear it we
* could end up clearing it again and the interrupt handler
* thinking it hasn't fired. Therefore we need to keep trying to
* retrigger until the bit is set.
*/
if (metag_in32(HWSTATMETA) & bit) {
metag_out32(bit, HWSTATMETA);
while (!(metag_in32(HWSTATMETA) & bit))
metag_out32(bit, HWSTATMETA);
}
}
#ifdef CONFIG_SMP
/*
* metag_internal_irq_set_affinity - set the affinity for an interrupt
*/
static int metag_internal_irq_set_affinity(struct irq_data *data,
const struct cpumask *cpumask, bool force)
{
unsigned int cpu, thread;
irq_hw_number_t hw = data->hwirq;
/*
* Wire up this interrupt from *VECINT to the Meta core.
*
* Note that we can't wire up *VECINT to interrupt more than
* one cpu (the interrupt code doesn't support it), so we just
* pick the first cpu we find in 'cpumask'.
*/
cpu = cpumask_any(cpumask);
thread = cpu_2_hwthread_id[cpu];
metag_out32(TBI_TRIG_VEC(TBID_SIGNUM_TR1(thread)),
metag_hwvec_addr(hw));
return 0;
}
#endif
/*
* metag_internal_irq_demux - irq de-multiplexer
* @irq: the interrupt number
* @desc: the interrupt description structure for this irq
*
* The cpu receives an interrupt on TR1 when an interrupt has
* occurred. It is this function's job to demux this irq and
* figure out exactly which trigger needs servicing.
*/
static void metag_internal_irq_demux(unsigned int irq, struct irq_desc *desc)
{
struct metag_internal_irq_priv *priv = irq_desc_get_handler_data(desc);
irq_hw_number_t hw;
unsigned int irq_no;
u32 status;
recalculate:
status = metag_in32(HWSTATMETA) & priv->unmasked;
for (hw = 0; status != 0; status >>= 1, ++hw) {
if (status & 0x1) {
/*
* Map the hardware IRQ number to a virtual Linux IRQ
* number.
*/
irq_no = irq_linear_revmap(priv->domain, hw);
/*
* Only fire off interrupts that are
* registered to be handled by the kernel.
* Other interrupts are probably being
* handled by other Meta hardware threads.
*/
generic_handle_irq(irq_no);
/*
* The handler may have re-enabled interrupts
* which could have caused a nested invocation
* of this code and make the copy of the
* status register we are using invalid.
*/
goto recalculate;
}
}
}
/**
* internal_irq_map() - Map an internal meta IRQ to a virtual IRQ number.
* @hw: Number of the internal IRQ. Must be in range.
*
* Returns: The virtual IRQ number of the Meta internal IRQ specified by
* @hw.
*/
int internal_irq_map(unsigned int hw)
{
struct metag_internal_irq_priv *priv = &metag_internal_irq_priv;
if (!priv->domain)
return -ENODEV;
return irq_create_mapping(priv->domain, hw);
}
/**
* metag_internal_irq_init_cpu - regsister with the Meta cpu
* @cpu: the CPU to register on
*
* Configure @cpu's TR1 irq so that we can demux irqs.
*/
static void metag_internal_irq_init_cpu(struct metag_internal_irq_priv *priv,
int cpu)
{
unsigned int thread = cpu_2_hwthread_id[cpu];
unsigned int signum = TBID_SIGNUM_TR1(thread);
int irq = tbisig_map(signum);
/* Register the multiplexed IRQ handler */
irq_set_handler_data(irq, priv);
irq_set_chained_handler(irq, metag_internal_irq_demux);
irq_set_irq_type(irq, IRQ_TYPE_LEVEL_LOW);
}
/**
* metag_internal_intc_map() - map an internal irq
* @d: irq domain of internal trigger block
* @irq: virtual irq number
* @hw: hardware irq number within internal trigger block
*
* This sets up a virtual irq for a specified hardware interrupt. The irq chip
* and handler is configured.
*/
static int metag_internal_intc_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
/* only register interrupt if it is mapped */
if (!metag_hwvec_addr(hw))
return -EINVAL;
irq_set_chip_and_handler(irq, &internal_irq_edge_chip,
handle_edge_irq);
return 0;
}
static const struct irq_domain_ops metag_internal_intc_domain_ops = {
.map = metag_internal_intc_map,
};
/**
* metag_internal_irq_register - register internal IRQs
*
* Register the irq chip and handler function for all internal IRQs
*/
int __init init_internal_IRQ(void)
{
struct metag_internal_irq_priv *priv = &metag_internal_irq_priv;
unsigned int cpu;
/* Set up an IRQ domain */
priv->domain = irq_domain_add_linear(NULL, 32,
&metag_internal_intc_domain_ops,
priv);
if (unlikely(!priv->domain)) {
pr_err("meta-internal-intc: cannot add IRQ domain\n");
return -ENOMEM;
}
/* Setup TR1 for all cpus. */
for_each_possible_cpu(cpu)
metag_internal_irq_init_cpu(priv, cpu);
return 0;
};

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include/linux/irqchip/metag-ext.h Normal file
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/*
* Copyright (C) 2012 Imagination Technologies
*/
#ifndef _LINUX_IRQCHIP_METAG_EXT_H_
#define _LINUX_IRQCHIP_METAG_EXT_H_
struct irq_data;
struct platform_device;
/* called from core irq code at init */
int init_external_IRQ(void);
/*
* called from SoC init_irq() callback to dynamically indicate the lack of
* HWMASKEXT registers.
*/
void meta_intc_no_mask(void);
/*
* These allow SoCs to specialise the interrupt controller from their init_irq
* callbacks.
*/
extern struct irq_chip meta_intc_edge_chip;
extern struct irq_chip meta_intc_level_chip;
/* this should be called in the mask callback */
void meta_intc_mask_irq_simple(struct irq_data *data);
/* this should be called in the unmask callback */
void meta_intc_unmask_irq_simple(struct irq_data *data);
#endif /* _LINUX_IRQCHIP_METAG_EXT_H_ */

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include/linux/irqchip/metag.h Normal file
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/*
* Copyright (C) 2011 Imagination Technologies
*/
#ifndef _LINUX_IRQCHIP_METAG_H_
#define _LINUX_IRQCHIP_METAG_H_
#include <linux/errno.h>
#ifdef CONFIG_METAG_PERFCOUNTER_IRQS
extern int init_internal_IRQ(void);
extern int internal_irq_map(unsigned int hw);
#else
static inline int init_internal_IRQ(void)
{
return 0;
}
static inline int internal_irq_map(unsigned int hw)
{
return -EINVAL;
}
#endif
#endif /* _LINUX_IRQCHIP_METAG_H_ */