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MIPS: alchemy: Remove pointless irqdisable/enable

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bcsr_csc_handler() is a cascading interrupt handler. It has a
disable_irq_nosync()/enable_irq() pair around the generic_handle_irq()
call. The value of this disable/enable is zero because its a complete
noop:

disable_irq_nosync() merily increments the disable count without
actually masking the interrupt. enable_irq() soleley decrements the
disable count without touching the interrupt chip. The interrupt
cannot arrive again because the complete call chain runs with
interrupts disabled.

Remove it.

[ralf@linux-mips.org: Fold in followup fix from Thomas Gleixner.]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: LKML <linux-kernel@vger.kernel.org>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Patchwork: https://patchwork.linux-mips.org/patch/10702/
Patchwork: https://patchwork.linux-mips.org/patch/10708/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Thomas Gleixner 2015-07-13 20:46:04 +00:00 committed by Ralf Baechle
parent 9154566ee3
commit e0288a0a7b
1 changed files with 4 additions and 2 deletions
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6
arch/mips/alchemy/devboards/bcsr.c
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@ -8,6 +8,7 @@
*/
#include <linux/interrupt.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/irq.h>
@ -88,10 +89,11 @@ EXPORT_SYMBOL_GPL(bcsr_mod);
static void bcsr_csc_handler(unsigned int irq, struct irq_desc *d)
{
unsigned short bisr = __raw_readw(bcsr_virt + BCSR_REG_INTSTAT);
struct irq_chip *chip = irq_desc_get_chip(d);
disable_irq_nosync(irq);
chained_irq_enter(chip, d);
generic_handle_irq(bcsr_csc_base + __ffs(bisr));
enable_irq(irq);
chained_irq_exit(chip, d);
}
static void bcsr_irq_mask(struct irq_data *d)