|  | /* | 
|  | * 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; | 
|  | } | 
|  |  | 
|  | 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); |