![Tony Lindgren](/assets/img/avatar_default.png)
There's no need to have this file in plat/fpga.h. We can make it local to plat-omap replacing fpga_read/write functions directly with readb/writeb as that's how they are already defined in fpga.h. Note that 2420 based H4 is also using the fpga, so let's keep the led support around in plat-omap until we flip over mach-omap2 to device tree. Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: linux-fbdev@vger.kernel.org Cc: Felipe Balbi <balbi@ti.com> Cc: linux-usb@vger.kernel.org Signed-off-by: Tony Lindgren <tony@atomide.com>
192 lines
5.2 KiB
C
192 lines
5.2 KiB
C
/*
|
|
* linux/arch/arm/mach-omap1/fpga.c
|
|
*
|
|
* Interrupt handler for OMAP-1510 Innovator FPGA
|
|
*
|
|
* Copyright (C) 2001 RidgeRun, Inc.
|
|
* Author: Greg Lonnon <glonnon@ridgerun.com>
|
|
*
|
|
* Copyright (C) 2002 MontaVista Software, Inc.
|
|
*
|
|
* Separated FPGA interrupts from innovator1510.c and cleaned up for 2.6
|
|
* Copyright (C) 2004 Nokia Corporation by Tony Lindrgen <tony@atomide.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/gpio.h>
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/device.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/io.h>
|
|
|
|
#include <asm/irq.h>
|
|
#include <asm/mach/irq.h>
|
|
|
|
#include <../plat-omap/fpga.h>
|
|
|
|
#include <mach/hardware.h>
|
|
|
|
#include "iomap.h"
|
|
|
|
static void fpga_mask_irq(struct irq_data *d)
|
|
{
|
|
unsigned int irq = d->irq - OMAP_FPGA_IRQ_BASE;
|
|
|
|
if (irq < 8)
|
|
__raw_writeb((__raw_readb(OMAP1510_FPGA_IMR_LO)
|
|
& ~(1 << irq)), OMAP1510_FPGA_IMR_LO);
|
|
else if (irq < 16)
|
|
__raw_writeb((__raw_readb(OMAP1510_FPGA_IMR_HI)
|
|
& ~(1 << (irq - 8))), OMAP1510_FPGA_IMR_HI);
|
|
else
|
|
__raw_writeb((__raw_readb(INNOVATOR_FPGA_IMR2)
|
|
& ~(1 << (irq - 16))), INNOVATOR_FPGA_IMR2);
|
|
}
|
|
|
|
|
|
static inline u32 get_fpga_unmasked_irqs(void)
|
|
{
|
|
return
|
|
((__raw_readb(OMAP1510_FPGA_ISR_LO) &
|
|
__raw_readb(OMAP1510_FPGA_IMR_LO))) |
|
|
((__raw_readb(OMAP1510_FPGA_ISR_HI) &
|
|
__raw_readb(OMAP1510_FPGA_IMR_HI)) << 8) |
|
|
((__raw_readb(INNOVATOR_FPGA_ISR2) &
|
|
__raw_readb(INNOVATOR_FPGA_IMR2)) << 16);
|
|
}
|
|
|
|
|
|
static void fpga_ack_irq(struct irq_data *d)
|
|
{
|
|
/* Don't need to explicitly ACK FPGA interrupts */
|
|
}
|
|
|
|
static void fpga_unmask_irq(struct irq_data *d)
|
|
{
|
|
unsigned int irq = d->irq - OMAP_FPGA_IRQ_BASE;
|
|
|
|
if (irq < 8)
|
|
__raw_writeb((__raw_readb(OMAP1510_FPGA_IMR_LO) | (1 << irq)),
|
|
OMAP1510_FPGA_IMR_LO);
|
|
else if (irq < 16)
|
|
__raw_writeb((__raw_readb(OMAP1510_FPGA_IMR_HI)
|
|
| (1 << (irq - 8))), OMAP1510_FPGA_IMR_HI);
|
|
else
|
|
__raw_writeb((__raw_readb(INNOVATOR_FPGA_IMR2)
|
|
| (1 << (irq - 16))), INNOVATOR_FPGA_IMR2);
|
|
}
|
|
|
|
static void fpga_mask_ack_irq(struct irq_data *d)
|
|
{
|
|
fpga_mask_irq(d);
|
|
fpga_ack_irq(d);
|
|
}
|
|
|
|
static void innovator_fpga_IRQ_demux(unsigned int irq, struct irq_desc *desc)
|
|
{
|
|
u32 stat;
|
|
int fpga_irq;
|
|
|
|
stat = get_fpga_unmasked_irqs();
|
|
|
|
if (!stat)
|
|
return;
|
|
|
|
for (fpga_irq = OMAP_FPGA_IRQ_BASE;
|
|
(fpga_irq < OMAP_FPGA_IRQ_END) && stat;
|
|
fpga_irq++, stat >>= 1) {
|
|
if (stat & 1) {
|
|
generic_handle_irq(fpga_irq);
|
|
}
|
|
}
|
|
}
|
|
|
|
static struct irq_chip omap_fpga_irq_ack = {
|
|
.name = "FPGA-ack",
|
|
.irq_ack = fpga_mask_ack_irq,
|
|
.irq_mask = fpga_mask_irq,
|
|
.irq_unmask = fpga_unmask_irq,
|
|
};
|
|
|
|
|
|
static struct irq_chip omap_fpga_irq = {
|
|
.name = "FPGA",
|
|
.irq_ack = fpga_ack_irq,
|
|
.irq_mask = fpga_mask_irq,
|
|
.irq_unmask = fpga_unmask_irq,
|
|
};
|
|
|
|
/*
|
|
* All of the FPGA interrupt request inputs except for the touchscreen are
|
|
* edge-sensitive; the touchscreen is level-sensitive. The edge-sensitive
|
|
* interrupts are acknowledged as a side-effect of reading the interrupt
|
|
* status register from the FPGA. The edge-sensitive interrupt inputs
|
|
* cause a problem with level interrupt requests, such as Ethernet. The
|
|
* problem occurs when a level interrupt request is asserted while its
|
|
* interrupt input is masked in the FPGA, which results in a missed
|
|
* interrupt.
|
|
*
|
|
* In an attempt to workaround the problem with missed interrupts, the
|
|
* mask_ack routine for all of the FPGA interrupts has been changed from
|
|
* fpga_mask_ack_irq() to fpga_ack_irq() so that the specific FPGA interrupt
|
|
* being serviced is left unmasked. We can do this because the FPGA cascade
|
|
* interrupt is installed with the IRQF_DISABLED flag, which leaves all
|
|
* interrupts masked at the CPU while an FPGA interrupt handler executes.
|
|
*
|
|
* Limited testing indicates that this workaround appears to be effective
|
|
* for the smc9194 Ethernet driver used on the Innovator. It should work
|
|
* on other FPGA interrupts as well, but any drivers that explicitly mask
|
|
* interrupts at the interrupt controller via disable_irq/enable_irq
|
|
* could pose a problem.
|
|
*/
|
|
void omap1510_fpga_init_irq(void)
|
|
{
|
|
int i, res;
|
|
|
|
__raw_writeb(0, OMAP1510_FPGA_IMR_LO);
|
|
__raw_writeb(0, OMAP1510_FPGA_IMR_HI);
|
|
__raw_writeb(0, INNOVATOR_FPGA_IMR2);
|
|
|
|
for (i = OMAP_FPGA_IRQ_BASE; i < OMAP_FPGA_IRQ_END; i++) {
|
|
|
|
if (i == OMAP1510_INT_FPGA_TS) {
|
|
/*
|
|
* The touchscreen interrupt is level-sensitive, so
|
|
* we'll use the regular mask_ack routine for it.
|
|
*/
|
|
irq_set_chip(i, &omap_fpga_irq_ack);
|
|
}
|
|
else {
|
|
/*
|
|
* All FPGA interrupts except the touchscreen are
|
|
* edge-sensitive, so we won't mask them.
|
|
*/
|
|
irq_set_chip(i, &omap_fpga_irq);
|
|
}
|
|
|
|
irq_set_handler(i, handle_edge_irq);
|
|
set_irq_flags(i, IRQF_VALID);
|
|
}
|
|
|
|
/*
|
|
* The FPGA interrupt line is connected to GPIO13. Claim this pin for
|
|
* the ARM.
|
|
*
|
|
* NOTE: For general GPIO/MPUIO access and interrupts, please see
|
|
* gpio.[ch]
|
|
*/
|
|
res = gpio_request(13, "FPGA irq");
|
|
if (res) {
|
|
pr_err("%s failed to get gpio\n", __func__);
|
|
return;
|
|
}
|
|
gpio_direction_input(13);
|
|
irq_set_irq_type(gpio_to_irq(13), IRQ_TYPE_EDGE_RISING);
|
|
irq_set_chained_handler(OMAP1510_INT_FPGA, innovator_fpga_IRQ_demux);
|
|
}
|