| /* |
| * 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 <linux/of.h> |
| #include <mach/qmgr.h> |
| |
| #include "irqs.h" |
| |
| static struct qmgr_regs __iomem *qmgr_regs = IXP4XX_QMGR_BASE_VIRT; |
| static struct resource *mem_res; |
| static spinlock_t qmgr_lock; |
| static u32 used_sram_bitmap[4]; /* 128 16-dword pages */ |
| static void (*irq_handlers[QUEUES])(void *pdev); |
| static void *irq_pdevs[QUEUES]; |
| |
| #if DEBUG_QMGR |
| char qmgr_queue_descs[QUEUES][32]; |
| #endif |
| |
| void qmgr_set_irq(unsigned int queue, int src, |
| void (*handler)(void *pdev), void *pdev) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&qmgr_lock, flags); |
| if (queue < HALF_QUEUES) { |
| u32 __iomem *reg; |
| int bit; |
| BUG_ON(src > QUEUE_IRQ_SRC_NOT_FULL); |
| reg = &qmgr_regs->irqsrc[queue >> 3]; /* 8 queues per u32 */ |
| bit = (queue % 8) * 4; /* 3 bits + 1 reserved bit per queue */ |
| __raw_writel((__raw_readl(reg) & ~(7 << bit)) | (src << bit), |
| reg); |
| } else |
| /* IRQ source for queues 32-63 is fixed */ |
| BUG_ON(src != QUEUE_IRQ_SRC_NOT_NEARLY_EMPTY); |
| |
| irq_handlers[queue] = handler; |
| irq_pdevs[queue] = pdev; |
| spin_unlock_irqrestore(&qmgr_lock, flags); |
| } |
| |
| |
| static irqreturn_t qmgr_irq1_a0(int irq, void *pdev) |
| { |
| int i, ret = 0; |
| u32 en_bitmap, src, stat; |
| |
| /* ACK - it may clear any bits so don't rely on it */ |
| __raw_writel(0xFFFFFFFF, &qmgr_regs->irqstat[0]); |
| |
| en_bitmap = qmgr_regs->irqen[0]; |
| while (en_bitmap) { |
| i = __fls(en_bitmap); /* number of the last "low" queue */ |
| en_bitmap &= ~BIT(i); |
| src = qmgr_regs->irqsrc[i >> 3]; |
| stat = qmgr_regs->stat1[i >> 3]; |
| if (src & 4) /* the IRQ condition is inverted */ |
| stat = ~stat; |
| if (stat & BIT(src & 3)) { |
| irq_handlers[i](irq_pdevs[i]); |
| ret = IRQ_HANDLED; |
| } |
| } |
| return ret; |
| } |
| |
| |
| static irqreturn_t qmgr_irq2_a0(int irq, void *pdev) |
| { |
| int i, ret = 0; |
| u32 req_bitmap; |
| |
| /* ACK - it may clear any bits so don't rely on it */ |
| __raw_writel(0xFFFFFFFF, &qmgr_regs->irqstat[1]); |
| |
| req_bitmap = qmgr_regs->irqen[1] & qmgr_regs->statne_h; |
| while (req_bitmap) { |
| i = __fls(req_bitmap); /* number of the last "high" queue */ |
| req_bitmap &= ~BIT(i); |
| irq_handlers[HALF_QUEUES + i](irq_pdevs[HALF_QUEUES + i]); |
| ret = IRQ_HANDLED; |
| } |
| return ret; |
| } |
| |
| |
| static irqreturn_t qmgr_irq(int irq, void *pdev) |
| { |
| int i, half = (irq == IRQ_IXP4XX_QM1 ? 0 : 1); |
| u32 req_bitmap = __raw_readl(&qmgr_regs->irqstat[half]); |
| |
| if (!req_bitmap) |
| return 0; |
| __raw_writel(req_bitmap, &qmgr_regs->irqstat[half]); /* ACK */ |
| |
| while (req_bitmap) { |
| i = __fls(req_bitmap); /* number of the last queue */ |
| req_bitmap &= ~BIT(i); |
| i += half * HALF_QUEUES; |
| irq_handlers[i](irq_pdevs[i]); |
| } |
| return IRQ_HANDLED; |
| } |
| |
| |
| void qmgr_enable_irq(unsigned int queue) |
| { |
| unsigned long flags; |
| int half = queue / 32; |
| u32 mask = 1 << (queue & (HALF_QUEUES - 1)); |
| |
| spin_lock_irqsave(&qmgr_lock, flags); |
| __raw_writel(__raw_readl(&qmgr_regs->irqen[half]) | mask, |
| &qmgr_regs->irqen[half]); |
| spin_unlock_irqrestore(&qmgr_lock, flags); |
| } |
| |
| void qmgr_disable_irq(unsigned int queue) |
| { |
| unsigned long flags; |
| int half = queue / 32; |
| u32 mask = 1 << (queue & (HALF_QUEUES - 1)); |
| |
| spin_lock_irqsave(&qmgr_lock, flags); |
| __raw_writel(__raw_readl(&qmgr_regs->irqen[half]) & ~mask, |
| &qmgr_regs->irqen[half]); |
| __raw_writel(mask, &qmgr_regs->irqstat[half]); /* clear */ |
| 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; |
| } |
| |
| #if DEBUG_QMGR |
| int qmgr_request_queue(unsigned int queue, unsigned int len /* dwords */, |
| unsigned int nearly_empty_watermark, |
| unsigned int nearly_full_watermark, |
| const char *desc_format, const char* name) |
| #else |
| int __qmgr_request_queue(unsigned int queue, unsigned int len /* dwords */, |
| unsigned int nearly_empty_watermark, |
| unsigned int nearly_full_watermark) |
| #endif |
| { |
| u32 cfg, addr = 0, mask[4]; /* in 16-dwords */ |
| int err; |
| |
| BUG_ON(queue >= QUEUES); |
| |
| 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]); |
| #if DEBUG_QMGR |
| snprintf(qmgr_queue_descs[queue], sizeof(qmgr_queue_descs[0]), |
| desc_format, name); |
| printk(KERN_DEBUG "qmgr: requested queue %s(%i) addr = 0x%02X\n", |
| qmgr_queue_descs[queue], queue, addr); |
| #endif |
| spin_unlock_irq(&qmgr_lock); |
| 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 >= 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); |
| |
| #if DEBUG_QMGR |
| printk(KERN_DEBUG "qmgr: releasing queue %s(%i)\n", |
| qmgr_queue_descs[queue], queue); |
| qmgr_queue_descs[queue][0] = '\x0'; |
| #endif |
| |
| while ((addr = qmgr_get_entry(queue))) |
| printk(KERN_ERR "qmgr: released queue %i not empty: 0x%08X\n", |
| queue, addr); |
| |
| __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); |
| } |
| |
| static int qmgr_init(void) |
| { |
| int i, err; |
| irq_handler_t handler1, handler2; |
| |
| /* This driver does not work with device tree */ |
| if (of_have_populated_dt()) |
| return -ENODEV; |
| |
| mem_res = request_mem_region(IXP4XX_QMGR_BASE_PHYS, |
| IXP4XX_QMGR_REGION_SIZE, |
| "IXP4xx Queue Manager"); |
| if (mem_res == NULL) |
| return -EBUSY; |
| |
| /* 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]); |
| } |
| |
| __raw_writel(0xFFFFFFFF, &qmgr_regs->statne_h); |
| __raw_writel(0, &qmgr_regs->statf_h); |
| |
| for (i = 0; i < QUEUES; i++) |
| __raw_writel(0, &qmgr_regs->sram[i]); |
| |
| if (cpu_is_ixp42x_rev_a0()) { |
| handler1 = qmgr_irq1_a0; |
| handler2 = qmgr_irq2_a0; |
| } else |
| handler1 = handler2 = qmgr_irq; |
| |
| err = request_irq(IRQ_IXP4XX_QM1, handler1, 0, "IXP4xx Queue Manager", |
| NULL); |
| if (err) { |
| printk(KERN_ERR "qmgr: failed to request IRQ%i (%i)\n", |
| IRQ_IXP4XX_QM1, err); |
| goto error_irq; |
| } |
| |
| err = request_irq(IRQ_IXP4XX_QM2, handler2, 0, "IXP4xx Queue Manager", |
| NULL); |
| if (err) { |
| printk(KERN_ERR "qmgr: failed to request IRQ%i (%i)\n", |
| IRQ_IXP4XX_QM2, err); |
| goto error_irq2; |
| } |
| |
| 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_irq2: |
| free_irq(IRQ_IXP4XX_QM1, NULL); |
| error_irq: |
| release_mem_region(IXP4XX_QMGR_BASE_PHYS, IXP4XX_QMGR_REGION_SIZE); |
| return err; |
| } |
| |
| static void qmgr_remove(void) |
| { |
| free_irq(IRQ_IXP4XX_QM1, NULL); |
| free_irq(IRQ_IXP4XX_QM2, NULL); |
| synchronize_irq(IRQ_IXP4XX_QM1); |
| synchronize_irq(IRQ_IXP4XX_QM2); |
| 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_set_irq); |
| EXPORT_SYMBOL(qmgr_enable_irq); |
| EXPORT_SYMBOL(qmgr_disable_irq); |
| #if DEBUG_QMGR |
| EXPORT_SYMBOL(qmgr_queue_descs); |
| EXPORT_SYMBOL(qmgr_request_queue); |
| #else |
| EXPORT_SYMBOL(__qmgr_request_queue); |
| #endif |
| EXPORT_SYMBOL(qmgr_release_queue); |