arch/arm/mach-ixp4xx/ixp4xx_qmgr.c - kernel/msm - Gitiles

 /*
  * Intel IXP4xx Queue Manager driver for Linux
  *
  * Copyright (C) 2007 Krzysztof Halasa <khc@pm.waw.pl>
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of version 2 of the GNU General Public License
  * as published by the Free Software Foundation.
  */

 #include <linux/ioport.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <asm/arch/qmgr.h>

 #define DEBUG		0

 struct qmgr_regs __iomem *qmgr_regs;
 static struct resource *mem_res;
 static spinlock_t qmgr_lock;
 static u32 used_sram_bitmap[4]; /* 128 16-dword pages */
 static void (*irq_handlers[HALF_QUEUES])(void *pdev);
 static void *irq_pdevs[HALF_QUEUES];

 void qmgr_set_irq(unsigned int queue, int src,
 		  void (*handler)(void *pdev), void *pdev)
 {
 	u32 __iomem *reg = &qmgr_regs->irqsrc[queue / 8]; /* 8 queues / u32 */
 	int bit = (queue % 8) * 4; /* 3 bits + 1 reserved bit per queue */
 	unsigned long flags;

 	src &= 7;
 	spin_lock_irqsave(&qmgr_lock, flags);
 	__raw_writel((__raw_readl(reg) & ~(7 << bit)) | (src << bit), reg);
 	irq_handlers[queue] = handler;
 	irq_pdevs[queue] = pdev;
 	spin_unlock_irqrestore(&qmgr_lock, flags);
 }


 static irqreturn_t qmgr_irq1(int irq, void *pdev)
 {
 	int i;
 	u32 val = __raw_readl(&qmgr_regs->irqstat[0]);
 	__raw_writel(val, &qmgr_regs->irqstat[0]); /* ACK */

 	for (i = 0; i < HALF_QUEUES; i++)
 		if (val & (1 << i))
 			irq_handlers[i](irq_pdevs[i]);

 	return val ? IRQ_HANDLED : 0;
 }


 void qmgr_enable_irq(unsigned int queue)
 {
 	unsigned long flags;

 	spin_lock_irqsave(&qmgr_lock, flags);
 	__raw_writel(__raw_readl(&qmgr_regs->irqen[0]) | (1 << queue),
 		     &qmgr_regs->irqen[0]);
 	spin_unlock_irqrestore(&qmgr_lock, flags);
 }

 void qmgr_disable_irq(unsigned int queue)
 {
 	unsigned long flags;

 	spin_lock_irqsave(&qmgr_lock, flags);
 	__raw_writel(__raw_readl(&qmgr_regs->irqen[0]) & ~(1 << queue),
 		     &qmgr_regs->irqen[0]);
 	spin_unlock_irqrestore(&qmgr_lock, flags);
 }

 static inline void shift_mask(u32 *mask)
 {
 	mask[3] = mask[3] << 1 | mask[2] >> 31;
 	mask[2] = mask[2] << 1 | mask[1] >> 31;
 	mask[1] = mask[1] << 1 | mask[0] >> 31;
 	mask[0] <<= 1;
 }

 int qmgr_request_queue(unsigned int queue, unsigned int len /* dwords */,
 		       unsigned int nearly_empty_watermark,
 		       unsigned int nearly_full_watermark)
 {
 	u32 cfg, addr = 0, mask[4]; /* in 16-dwords */
 	int err;

 	if (queue >= HALF_QUEUES)
 		return -ERANGE;

 	if ((nearly_empty_watermark | nearly_full_watermark) & ~7)
 		return -EINVAL;

 	switch (len) {
 	case  16:
 		cfg = 0 << 24;
 		mask[0] = 0x1;
 		break;
 	case  32:
 		cfg = 1 << 24;
 		mask[0] = 0x3;
 		break;
 	case  64:
 		cfg = 2 << 24;
 		mask[0] = 0xF;
 		break;
 	case 128:
 		cfg = 3 << 24;
 		mask[0] = 0xFF;
 		break;
 	default:
 		return -EINVAL;
 	}

 	cfg |= nearly_empty_watermark << 26;
 	cfg |= nearly_full_watermark << 29;
 	len /= 16;		/* in 16-dwords: 1, 2, 4 or 8 */
 	mask[1] = mask[2] = mask[3] = 0;

 	if (!try_module_get(THIS_MODULE))
 		return -ENODEV;

 	spin_lock_irq(&qmgr_lock);
 	if (__raw_readl(&qmgr_regs->sram[queue])) {
 		err = -EBUSY;
 		goto err;
 	}

 	while (1) {
 		if (!(used_sram_bitmap[0] & mask[0]) &&
 		    !(used_sram_bitmap[1] & mask[1]) &&
 		    !(used_sram_bitmap[2] & mask[2]) &&
 		    !(used_sram_bitmap[3] & mask[3]))
 			break; /* found free space */

 		addr++;
 		shift_mask(mask);
 		if (addr + len > ARRAY_SIZE(qmgr_regs->sram)) {
 			printk(KERN_ERR "qmgr: no free SRAM space for"
 			       " queue %i\n", queue);
 			err = -ENOMEM;
 			goto err;
 		}
 	}

 	used_sram_bitmap[0] |= mask[0];
 	used_sram_bitmap[1] |= mask[1];
 	used_sram_bitmap[2] |= mask[2];
 	used_sram_bitmap[3] |= mask[3];
 	__raw_writel(cfg | (addr << 14), &qmgr_regs->sram[queue]);
 	spin_unlock_irq(&qmgr_lock);

 #if DEBUG
 	printk(KERN_DEBUG "qmgr: requested queue %i, addr = 0x%02X\n",
 	       queue, addr);
 #endif
 	return 0;

 err:
 	spin_unlock_irq(&qmgr_lock);
 	module_put(THIS_MODULE);
 	return err;
 }

 void qmgr_release_queue(unsigned int queue)
 {
 	u32 cfg, addr, mask[4];

 	BUG_ON(queue >= HALF_QUEUES); /* not in valid range */

 	spin_lock_irq(&qmgr_lock);
 	cfg = __raw_readl(&qmgr_regs->sram[queue]);
 	addr = (cfg >> 14) & 0xFF;

 	BUG_ON(!addr);		/* not requested */

 	switch ((cfg >> 24) & 3) {
 	case 0: mask[0] = 0x1; break;
 	case 1: mask[0] = 0x3; break;
 	case 2: mask[0] = 0xF; break;
 	case 3: mask[0] = 0xFF; break;
 	}

 	mask[1] = mask[2] = mask[3] = 0;

 	while (addr--)
 		shift_mask(mask);

 	__raw_writel(0, &qmgr_regs->sram[queue]);

 	used_sram_bitmap[0] &= ~mask[0];
 	used_sram_bitmap[1] &= ~mask[1];
 	used_sram_bitmap[2] &= ~mask[2];
 	used_sram_bitmap[3] &= ~mask[3];
 	irq_handlers[queue] = NULL; /* catch IRQ bugs */
 	spin_unlock_irq(&qmgr_lock);

 	module_put(THIS_MODULE);
 #if DEBUG
 	printk(KERN_DEBUG "qmgr: released queue %i\n", queue);
 #endif
 }

 static int qmgr_init(void)
 {
 	int i, err;
 	mem_res = request_mem_region(IXP4XX_QMGR_BASE_PHYS,
 				     IXP4XX_QMGR_REGION_SIZE,
 				     "IXP4xx Queue Manager");
 	if (mem_res == NULL)
 		return -EBUSY;

 	qmgr_regs = ioremap(IXP4XX_QMGR_BASE_PHYS, IXP4XX_QMGR_REGION_SIZE);
 	if (qmgr_regs == NULL) {
 		err = -ENOMEM;
 		goto error_map;
 	}

 	/* reset qmgr registers */
 	for (i = 0; i < 4; i++) {
 		__raw_writel(0x33333333, &qmgr_regs->stat1[i]);
 		__raw_writel(0, &qmgr_regs->irqsrc[i]);
 	}
 	for (i = 0; i < 2; i++) {
 		__raw_writel(0, &qmgr_regs->stat2[i]);
 		__raw_writel(0xFFFFFFFF, &qmgr_regs->irqstat[i]); /* clear */
 		__raw_writel(0, &qmgr_regs->irqen[i]);
 	}

 	for (i = 0; i < QUEUES; i++)
 		__raw_writel(0, &qmgr_regs->sram[i]);

 	err = request_irq(IRQ_IXP4XX_QM1, qmgr_irq1, 0,
 			  "IXP4xx Queue Manager", NULL);
 	if (err) {
 		printk(KERN_ERR "qmgr: failed to request IRQ%i\n",
 		       IRQ_IXP4XX_QM1);
 		goto error_irq;
 	}

 	used_sram_bitmap[0] = 0xF; /* 4 first pages reserved for config */
 	spin_lock_init(&qmgr_lock);

 	printk(KERN_INFO "IXP4xx Queue Manager initialized.\n");
 	return 0;

 error_irq:
 	iounmap(qmgr_regs);
 error_map:
 	release_mem_region(IXP4XX_QMGR_BASE_PHYS, IXP4XX_QMGR_REGION_SIZE);
 	return err;
 }

 static void qmgr_remove(void)
 {
 	free_irq(IRQ_IXP4XX_QM1, NULL);
 	synchronize_irq(IRQ_IXP4XX_QM1);
 	iounmap(qmgr_regs);
 	release_mem_region(IXP4XX_QMGR_BASE_PHYS, IXP4XX_QMGR_REGION_SIZE);
 }

 module_init(qmgr_init);
 module_exit(qmgr_remove);

 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Krzysztof Halasa");

 EXPORT_SYMBOL(qmgr_regs);
 EXPORT_SYMBOL(qmgr_set_irq);
 EXPORT_SYMBOL(qmgr_enable_irq);
 EXPORT_SYMBOL(qmgr_disable_irq);
 EXPORT_SYMBOL(qmgr_request_queue);
 EXPORT_SYMBOL(qmgr_release_queue);
	/*
	* Intel IXP4xx Queue Manager driver for Linux
	*
	* Copyright (C) 2007 Krzysztof Halasa <khc@pm.waw.pl>
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms of version 2 of the GNU General Public License
	* as published by the Free Software Foundation.
	*/

	#include <linux/ioport.h>
	#include <linux/interrupt.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <asm/arch/qmgr.h>

	#define DEBUG 0

	struct qmgr_regs __iomem *qmgr_regs;
	static struct resource *mem_res;
	static spinlock_t qmgr_lock;
	static u32 used_sram_bitmap[4]; /* 128 16-dword pages */
	static void (irq_handlers[HALF_QUEUES])(void pdev);
	static void *irq_pdevs[HALF_QUEUES];

	void qmgr_set_irq(unsigned int queue, int src,
	void (handler)(void pdev), void *pdev)
	{
	u32 __iomem reg = &qmgr_regs->irqsrc[queue / 8]; / 8 queues / u32 */
	int bit = (queue % 8) * 4; /* 3 bits + 1 reserved bit per queue */
	unsigned long flags;

	src &= 7;
	spin_lock_irqsave(&qmgr_lock, flags);
	__raw_writel((__raw_readl(reg) & ~(7 << bit)) \| (src << bit), reg);
	irq_handlers[queue] = handler;
	irq_pdevs[queue] = pdev;
	spin_unlock_irqrestore(&qmgr_lock, flags);
	}


	static irqreturn_t qmgr_irq1(int irq, void *pdev)
	{
	int i;
	u32 val = __raw_readl(&qmgr_regs->irqstat[0]);
	__raw_writel(val, &qmgr_regs->irqstat[0]); /* ACK */

	for (i = 0; i < HALF_QUEUES; i++)
	if (val & (1 << i))
	irq_handlers[i](irq_pdevs[i]);

	return val ? IRQ_HANDLED : 0;
	}


	void qmgr_enable_irq(unsigned int queue)
	{
	unsigned long flags;

	spin_lock_irqsave(&qmgr_lock, flags);
	__raw_writel(__raw_readl(&qmgr_regs->irqen[0]) \| (1 << queue),
	&qmgr_regs->irqen[0]);
	spin_unlock_irqrestore(&qmgr_lock, flags);
	}

	void qmgr_disable_irq(unsigned int queue)
	{
	unsigned long flags;

	spin_lock_irqsave(&qmgr_lock, flags);
	__raw_writel(__raw_readl(&qmgr_regs->irqen[0]) & ~(1 << queue),
	&qmgr_regs->irqen[0]);
	spin_unlock_irqrestore(&qmgr_lock, flags);
	}

	static inline void shift_mask(u32 *mask)
	{
	mask[3] = mask[3] << 1 \| mask[2] >> 31;
	mask[2] = mask[2] << 1 \| mask[1] >> 31;
	mask[1] = mask[1] << 1 \| mask[0] >> 31;
	mask[0] <<= 1;
	}

	int qmgr_request_queue(unsigned int queue, unsigned int len /* dwords */,
	unsigned int nearly_empty_watermark,
	unsigned int nearly_full_watermark)
	{
	u32 cfg, addr = 0, mask[4]; /* in 16-dwords */
	int err;

	if (queue >= HALF_QUEUES)
	return -ERANGE;

	if ((nearly_empty_watermark \| nearly_full_watermark) & ~7)
	return -EINVAL;

	switch (len) {
	case 16:
	cfg = 0 << 24;
	mask[0] = 0x1;
	break;
	case 32:
	cfg = 1 << 24;
	mask[0] = 0x3;
	break;
	case 64:
	cfg = 2 << 24;
	mask[0] = 0xF;
	break;
	case 128:
	cfg = 3 << 24;
	mask[0] = 0xFF;
	break;
	default:
	return -EINVAL;
	}

	cfg \|= nearly_empty_watermark << 26;
	cfg \|= nearly_full_watermark << 29;
	len /= 16; /* in 16-dwords: 1, 2, 4 or 8 */
	mask[1] = mask[2] = mask[3] = 0;

	if (!try_module_get(THIS_MODULE))
	return -ENODEV;

	spin_lock_irq(&qmgr_lock);
	if (__raw_readl(&qmgr_regs->sram[queue])) {
	err = -EBUSY;
	goto err;
	}

	while (1) {
	if (!(used_sram_bitmap[0] & mask[0]) &&
	!(used_sram_bitmap[1] & mask[1]) &&
	!(used_sram_bitmap[2] & mask[2]) &&
	!(used_sram_bitmap[3] & mask[3]))
	break; /* found free space */

	addr++;
	shift_mask(mask);
	if (addr + len > ARRAY_SIZE(qmgr_regs->sram)) {
	printk(KERN_ERR "qmgr: no free SRAM space for"
	" queue %i\n", queue);
	err = -ENOMEM;
	goto err;
	}
	}

	used_sram_bitmap[0] \|= mask[0];
	used_sram_bitmap[1] \|= mask[1];
	used_sram_bitmap[2] \|= mask[2];
	used_sram_bitmap[3] \|= mask[3];
	__raw_writel(cfg \| (addr << 14), &qmgr_regs->sram[queue]);
	spin_unlock_irq(&qmgr_lock);

	#if DEBUG
	printk(KERN_DEBUG "qmgr: requested queue %i, addr = 0x%02X\n",
	queue, addr);
	#endif
	return 0;

	err:
	spin_unlock_irq(&qmgr_lock);
	module_put(THIS_MODULE);
	return err;
	}

	void qmgr_release_queue(unsigned int queue)
	{
	u32 cfg, addr, mask[4];

	BUG_ON(queue >= HALF_QUEUES); /* not in valid range */

	spin_lock_irq(&qmgr_lock);
	cfg = __raw_readl(&qmgr_regs->sram[queue]);
	addr = (cfg >> 14) & 0xFF;

	BUG_ON(!addr); /* not requested */

	switch ((cfg >> 24) & 3) {
	case 0: mask[0] = 0x1; break;
	case 1: mask[0] = 0x3; break;
	case 2: mask[0] = 0xF; break;
	case 3: mask[0] = 0xFF; break;
	}

	mask[1] = mask[2] = mask[3] = 0;

	while (addr--)
	shift_mask(mask);

	__raw_writel(0, &qmgr_regs->sram[queue]);

	used_sram_bitmap[0] &= ~mask[0];
	used_sram_bitmap[1] &= ~mask[1];
	used_sram_bitmap[2] &= ~mask[2];
	used_sram_bitmap[3] &= ~mask[3];
	irq_handlers[queue] = NULL; /* catch IRQ bugs */
	spin_unlock_irq(&qmgr_lock);

	module_put(THIS_MODULE);
	#if DEBUG
	printk(KERN_DEBUG "qmgr: released queue %i\n", queue);
	#endif
	}

	static int qmgr_init(void)
	{
	int i, err;
	mem_res = request_mem_region(IXP4XX_QMGR_BASE_PHYS,
	IXP4XX_QMGR_REGION_SIZE,
	"IXP4xx Queue Manager");
	if (mem_res == NULL)
	return -EBUSY;

	qmgr_regs = ioremap(IXP4XX_QMGR_BASE_PHYS, IXP4XX_QMGR_REGION_SIZE);
	if (qmgr_regs == NULL) {
	err = -ENOMEM;
	goto error_map;
	}

	/* reset qmgr registers */
	for (i = 0; i < 4; i++) {
	__raw_writel(0x33333333, &qmgr_regs->stat1[i]);
	__raw_writel(0, &qmgr_regs->irqsrc[i]);
	}
	for (i = 0; i < 2; i++) {
	__raw_writel(0, &qmgr_regs->stat2[i]);
	__raw_writel(0xFFFFFFFF, &qmgr_regs->irqstat[i]); /* clear */
	__raw_writel(0, &qmgr_regs->irqen[i]);
	}

	for (i = 0; i < QUEUES; i++)
	__raw_writel(0, &qmgr_regs->sram[i]);

	err = request_irq(IRQ_IXP4XX_QM1, qmgr_irq1, 0,
	"IXP4xx Queue Manager", NULL);
	if (err) {
	printk(KERN_ERR "qmgr: failed to request IRQ%i\n",
	IRQ_IXP4XX_QM1);
	goto error_irq;
	}

	used_sram_bitmap[0] = 0xF; /* 4 first pages reserved for config */
	spin_lock_init(&qmgr_lock);

	printk(KERN_INFO "IXP4xx Queue Manager initialized.\n");
	return 0;

	error_irq:
	iounmap(qmgr_regs);
	error_map:
	release_mem_region(IXP4XX_QMGR_BASE_PHYS, IXP4XX_QMGR_REGION_SIZE);
	return err;
	}

	static void qmgr_remove(void)
	{
	free_irq(IRQ_IXP4XX_QM1, NULL);
	synchronize_irq(IRQ_IXP4XX_QM1);
	iounmap(qmgr_regs);
	release_mem_region(IXP4XX_QMGR_BASE_PHYS, IXP4XX_QMGR_REGION_SIZE);
	}

	module_init(qmgr_init);
	module_exit(qmgr_remove);

	MODULE_LICENSE("GPL v2");
	MODULE_AUTHOR("Krzysztof Halasa");

	EXPORT_SYMBOL(qmgr_regs);
	EXPORT_SYMBOL(qmgr_set_irq);
	EXPORT_SYMBOL(qmgr_enable_irq);
	EXPORT_SYMBOL(qmgr_disable_irq);
	EXPORT_SYMBOL(qmgr_request_queue);
	EXPORT_SYMBOL(qmgr_release_queue);