The GPIO interrupts can be configured as either level triggered or edge
triggered, with a default of level triggered. When an edge triggered
interrupt is requested, the gpio_irq_set_type method is called which
currently switches the given IRQ descriptor between two struct irq_chip
instances: orion_gpio_irq_level_chip and orion_gpio_irq_edge_chip. This
happens via __setup_irq() which also calls irq_chip_set_defaults() to
assign default methods to uninitialized ones. The problem is that
irq_chip_set_defaults() is called before the irq_chip reference is
switched, leaving the new irq_chip (orion_gpio_irq_edge_chip in this
case) with uninitialized methods such as chip->startup() causing a kernel
oops.
Many solutions are possible, such as making irq_chip_set_defaults() global
and calling it from gpio_irq_set_type(), or calling __irq_set_trigger()
before irq_chip_set_defaults() in __setup_irq(). But those require
modifications to the generic IRQ code which might have adverse effect on
other architectures, and that would still be a fragile arrangement.
Manually copying the missing methods from within gpio_irq_set_type()
would be really ugly and it would break again the day new methods with
automatic defaults are added.
A better solution is to have a single irq_chip instance which can deal
with both edge and level triggered interrupts. It is also a good idea
to switch the IRQ handler instead, as the edge IRQ handler allows for
one edge IRQ event to be queued as the IRQ is actually masked only when
that second IRQ is received, at which point the hardware can queue an
additional IRQ event, making edge triggered interrupts a bit more
reliable.
Tested-by: Martin Michlmayr <tbm@cyrius.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (66 commits)
x86: export vector_used_by_percpu_irq
x86: use logical apicid in x2apic_cluster's x2apic_cpu_mask_to_apicid_and()
sched: nominate preferred wakeup cpu, fix
x86: fix lguest used_vectors breakage, -v2
x86: fix warning in arch/x86/kernel/io_apic.c
sched: fix warning in kernel/sched.c
sched: move test_sd_parent() to an SMP section of sched.h
sched: add SD_BALANCE_NEWIDLE at MC and CPU level for sched_mc>0
sched: activate active load balancing in new idle cpus
sched: bias task wakeups to preferred semi-idle packages
sched: nominate preferred wakeup cpu
sched: favour lower logical cpu number for sched_mc balance
sched: framework for sched_mc/smt_power_savings=N
sched: convert BALANCE_FOR_xx_POWER to inline functions
x86: use possible_cpus=NUM to extend the possible cpus allowed
x86: fix cpu_mask_to_apicid_and to include cpu_online_mask
x86: update io_apic.c to the new cpumask code
x86: Introduce topology_core_cpumask()/topology_thread_cpumask()
x86: xen: use smp_call_function_many()
x86: use work_on_cpu in x86/kernel/cpu/mcheck/mce_amd_64.c
...
Fixed up trivial conflict in kernel/time/tick-sched.c manually
Split off Orion GPIO handling code into plat-orion/, and add
support for multiple sets of (32) GPIO pins.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Impact: change calling convention of existing clock_event APIs
struct clock_event_timer's cpumask field gets changed to take pointer,
as does the ->broadcast function.
Another single-patch change. For safety, we BUG_ON() in
clockevents_register_device() if it's not set.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
The Orion ehci driver serves the Orion, kirkwood and DD Soc families.
Since each of those integrate a different USB phy we should have the
ability to use few initialization sequences or to leave the boot loader
phy settings as is.
Signed-off-by: Ronen Shitrit <rshitrit@marvell.com>
This patch performs the equivalent include directory shuffle for
plat-orion, and fixes up all users.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
The Discovery Duo (MV78xx0) has two x4 PCIe ports which can either
be used in x4 mode or in quad x1 mode. This patch adds an accessor
function to the generic plat-orion PCIe handling code to detect in
which of the two modes we're running (which is determined by strap
pins and/or configured by the bootloader).
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Some Feroceon-based SoCs have an MBUS bridge interrupt controller
that requires writing a one instead of a zero to clear edge
interrupt sources such as timer expiry.
This patch adds a new BRIDGE_INT_TIMER1_CLR define, which platform
code can set to either ~BRIDGE_INT_TIMER1 (write-zero-to-clear) or
BRIDGE_INT_TIMER1 (write-one-to-clear) depending on the platform.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Make it clear that Orion top-level IRQs are level-triggered. This
means that we don't need an ->ack() handler, or at least, we don't
need the ->ack() handler (or the acking part of the ->mask_ack()
handler) to actually do anything.
Given that, we might as well point our ->mask_ack() handler at the
->mask() handler instead of providing a dummy ->ack() handler, since
providing a ->mask_ack() handler on level IRQ sources will prevent
->ack() from ever being called.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
Split off Orion time handling code into plat-orion/.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Reviewed-by: Tzachi Perelstein <tzachi@marvell.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Split off Orion PCIe handling code into plat-orion/.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Reviewed-by: Tzachi Perelstein <tzachi@marvell.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Split off Orion IRQ handling code into plat-orion/, and add
support for multiple sets of (32) interrupts.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Reviewed-by: Tzachi Perelstein <tzachi@marvell.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Create arch/arm/plat-orion/, for peripherals shared between various
Marvell Orion SoCs.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Reviewed-by: Tzachi Perelstein <tzachi@marvell.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
