sh: x3proto: ILSEL IRQ support.

obj-y += setup.o

obj-y += setup.o ilsel.o

/*

 * arch/sh/boards/renesas/x3proto/ilsel.c

 *

 * Helper routines for SH-X3 proto board ILSEL.

 *

 * Copyright (C) 2007 Paul Mundt

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file "COPYING" in the main directory of this archive

 * for more details.

 */

#include <linux/init.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/bitmap.h>

#include <linux/io.h>

#include <asm/ilsel.h>

/*

 * ILSEL is split across:

 *

 *	ILSEL0 - 0xb8100004 [ Levels  1 -  4 ]

 *	ILSEL1 - 0xb8100006 [ Levels  5 -  8 ]

 *	ILSEL2 - 0xb8100008 [ Levels  9 - 12 ]

 *	ILSEL3 - 0xb810000a [ Levels 13 - 15 ]

 *

 * With each level being relative to an ilsel_source_t.

 */

#define ILSEL_BASE	0xb8100004

#define ILSEL_LEVELS	15

/*

 * ILSEL level map, in descending order from the highest level down.

 *

 * Supported levels are 1 - 15 spread across ILSEL0 - ILSEL4, mapping

 * directly to IRLs. As the IRQs are numbered in reverse order relative

 * to the interrupt level, the level map is carefully managed to ensure a

 * 1:1 mapping between the bit position and the IRQ number.

 *

 * This careful constructions allows ilsel_enable*() to be referenced

 * directly for hooking up an ILSEL set and getting back an IRQ which can

 * subsequently be used for internal accounting in the (optional) disable

 * path.

 */

static unsigned long ilsel_level_map;

static inline unsigned int ilsel_offset(unsigned int bit)

{

	return ILSEL_LEVELS - bit - 1;

}

static inline unsigned long mk_ilsel_addr(unsigned int bit)

{

	return ILSEL_BASE + ((ilsel_offset(bit) >> 1) & ~0x1);

}

static inline unsigned int mk_ilsel_shift(unsigned int bit)

{

	return (ilsel_offset(bit) & 0x3) << 2;

}

static void __ilsel_enable(ilsel_source_t set, unsigned int bit)

{

	unsigned int tmp, shift;

	unsigned long addr;

	addr = mk_ilsel_addr(bit);

	shift = mk_ilsel_shift(bit);

	pr_debug("%s: bit#%d: addr - 0x%08lx (shift %d, set %d)\n",

		 __FUNCTION__, bit, addr, shift, set);

	tmp = ctrl_inw(addr);

	tmp &= ~(0xf << shift);

	tmp |= set << shift;

	ctrl_outw(tmp, addr);

}

/**

 * ilsel_enable - Enable an ILSEL set.

 * @set: ILSEL source (see ilsel_source_t enum in include/asm-sh/ilsel.h).

 *

 * Enables a given non-aliased ILSEL source (<= ILSEL_KEY) at the highest

 * available interrupt level. Callers should take care to order callsites

 * noting descending interrupt levels. Aliasing FPGA and external board

 * IRQs need to use ilsel_enable_fixed().

 *

 * The return value is an IRQ number that can later be taken down with

 * ilsel_disable().

 */

int ilsel_enable(ilsel_source_t set)

{

	unsigned int bit;

	/* Aliased sources must use ilsel_enable_fixed() */

	BUG_ON(set > ILSEL_KEY);

	do {

		bit = find_first_zero_bit(&ilsel_level_map, ILSEL_LEVELS);

	} while (test_and_set_bit(bit, &ilsel_level_map));

	__ilsel_enable(set, bit);

	return bit;

}

EXPORT_SYMBOL_GPL(ilsel_enable);

/**

 * ilsel_enable_fixed - Enable an ILSEL set at a fixed interrupt level

 * @set: ILSEL source (see ilsel_source_t enum in include/asm-sh/ilsel.h).

 * @level: Interrupt level (1 - 15)

 *

 * Enables a given ILSEL source at a fixed interrupt level. Necessary

 * both for level reservation as well as for aliased sources that only

 * exist on special ILSEL#s.

 *

 * Returns an IRQ number (as ilsel_enable()).

 */

int ilsel_enable_fixed(ilsel_source_t set, unsigned int level)

{

	unsigned int bit = ilsel_offset(level - 1);

	if (test_and_set_bit(bit, &ilsel_level_map))

		return -EBUSY;

	__ilsel_enable(set, bit);

	return bit;

}

EXPORT_SYMBOL_GPL(ilsel_enable_fixed);

/**

 * ilsel_disable - Disable an ILSEL set

 * @irq: Bit position for ILSEL set value (retval from enable routines)

 *

 * Disable a previously enabled ILSEL set.

 */

void ilsel_disable(unsigned int irq)

{

	unsigned long addr;

	unsigned int tmp;

	addr = mk_ilsel_addr(bit);

	tmp = ctrl_inw(addr);

	tmp &= ~(0xf << mk_ilsel_shift(bit));

	ctrl_outw(tmp, addr);

	clear_bit(bit, &ilsel_level_map);

}

EXPORT_SYMBOL_GPL(ilsel_disable);

#ifndef __ASM_SH_ILSEL_H

#define __ASM_SH_ILSEL_H

typedef enum {

	ILSEL_NONE,

	ILSEL_LAN,

	ILSEL_USBH_I,

	ILSEL_USBH_S,

	ILSEL_USBH_V,

	ILSEL_RTC,

	ILSEL_USBP_I,

	ILSEL_USBP_S,

	ILSEL_USBP_V,

	ILSEL_KEY,

	/*

	 * ILSEL Aliases - corner cases for interleaved level tables.

	 *

	 * Someone thought this was a good idea and less hassle than

	 * demuxing a shared vector, really.

	 */

	/* ILSEL0 and 2 */

	ILSEL_FPGA0,

	ILSEL_FPGA1,

	ILSEL_EX1,

	ILSEL_EX2,

	ILSEL_EX3,

	ILSEL_EX4,

	/* ILSEL1 and 3 */

	ILSEL_FPGA2 = ILSEL_FPGA0,

	ILSEL_FPGA3 = ILSEL_FPGA1,

	ILSEL_EX5 = ILSEL_EX1,

	ILSEL_EX6 = ILSEL_EX2,

	ILSEL_EX7 = ILSEL_EX3,

	ILSEL_EX8 = ILSEL_EX4,

} ilsel_source_t;

/* arch/sh/boards/renesas/x3proto/ilsel.c */

int ilsel_enable(ilsel_source_t set);

int ilsel_enable_fixed(ilsel_source_t set, unsigned int level);

void ilsel_disable(unsigned int irq);

#endif /* __ASM_SH_ILSEL_H */