kernel-ark/drivers/media/video/cx18/cx18-irq.c
Andy Walls ee2d64f5cc V4L/DVB (9720): cx18: Major rewrite of interrupt handling for incoming mailbox processing
A major rewrite of interrupt handling for incoming mailbox processing, to split
the timing critical steps from the the deferrable steps as the sending XPU on
the CX23418 will time out and overwrite our incoming mailboxes rather quickly.
Setup a pool of work "order forms" for the irq handler to send jobs to the new
work handler routine which uses the kernel default work queue to do the
deferrable work.  Started optimizing some of the cx18-io calls as they are now
the low hanging fruit for recoving microseconds back from the timeline.
Future optimizations will get rid of mmio read retries, mmio stats logging, and
combine smaller functions in the irq path into the larger ones to save ~2 us
each.

Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2008-12-30 09:38:07 -02:00

86 lines
2.4 KiB
C

/*
* cx18 interrupt handling
*
* Copyright (C) 2007 Hans Verkuil <hverkuil@xs4all.nl>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
* 02111-1307 USA
*/
#include "cx18-driver.h"
#include "cx18-io.h"
#include "cx18-irq.h"
#include "cx18-mailbox.h"
#include "cx18-scb.h"
static void xpu_ack(struct cx18 *cx, u32 sw2)
{
if (sw2 & IRQ_CPU_TO_EPU_ACK)
wake_up(&cx->mb_cpu_waitq);
if (sw2 & IRQ_APU_TO_EPU_ACK)
wake_up(&cx->mb_apu_waitq);
}
static void epu_cmd(struct cx18 *cx, u32 sw1)
{
if (sw1 & IRQ_CPU_TO_EPU)
cx18_api_epu_cmd_irq(cx, CPU);
if (sw1 & IRQ_APU_TO_EPU)
cx18_api_epu_cmd_irq(cx, APU);
}
irqreturn_t cx18_irq_handler(int irq, void *dev_id)
{
struct cx18 *cx = (struct cx18 *)dev_id;
u32 sw1, sw1_mask;
u32 sw2, sw2_mask;
u32 hw2, hw2_mask;
sw1_mask = cx18_read_reg(cx, SW1_INT_ENABLE_PCI);
sw1 = cx18_read_reg(cx, SW1_INT_STATUS) & sw1_mask;
sw2_mask = cx18_read_reg(cx, SW2_INT_ENABLE_PCI);
sw2 = cx18_read_reg(cx, SW2_INT_STATUS) & sw2_mask;
hw2_mask = cx18_read_reg(cx, HW2_INT_MASK5_PCI);
hw2 = cx18_read_reg(cx, HW2_INT_CLR_STATUS) & hw2_mask;
if (sw1)
cx18_write_reg_expect(cx, sw1, SW1_INT_STATUS, ~sw1, sw1);
if (sw2)
cx18_write_reg_expect(cx, sw2, SW2_INT_STATUS, ~sw2, sw2);
if (hw2)
cx18_write_reg_expect(cx, hw2, HW2_INT_CLR_STATUS, ~hw2, hw2);
if (sw1 || sw2 || hw2)
CX18_DEBUG_HI_IRQ("received interrupts "
"SW1: %x SW2: %x HW2: %x\n", sw1, sw2, hw2);
/*
* SW1 responses have to happen first. The sending XPU times out the
* incoming mailboxes on us rather rapidly.
*/
if (sw1)
epu_cmd(cx, sw1);
/* To do: interrupt-based I2C handling
if (hw2 & (HW2_I2C1_INT|HW2_I2C2_INT)) {
}
*/
if (sw2)
xpu_ack(cx, sw2);
return (sw1 || sw2 || hw2) ? IRQ_HANDLED : IRQ_NONE;
}